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64 results on '"Brain imaging (LIAMA)"'

1. Hospital and community surveys reveal the severe public health problem and socio-economic impact of human echinococcosis in Ningxia Hui Autonomous Region, China

Author: Donald P. McManus, X. Pan, S. K. Yang, Yu Rong Yang, Tao Sun, S. Hu, Patrick Giraudoux, Gail M. Williams, X. P. Li, Philip S. Craig, Dominique-Angèle Vuitton, L. Cheng, X. Liu, Ningxia Medical College, Biomedical Sciences Research Institute, University of Salford, WHO Collaborating Center on Prevention and Treatment of Human Echinococcosis, SERF Unit, Université de Franche-Comté (UFC), Carcinogénèse épithéliale : facteurs prédictifs et pronostiques - UFC (EA 3181) (CEF2P / CARCINO), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre Hospitalier Régional Universitaire [Besançon] (CHRU Besançon)-Université de Franche-Comté (UFC), Laboratoire Chrono-environnement - UFC (UMR 6249) (LCE), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Molecular Parasitology, University of Queensland [Brisbane]-Queensland Institute of Medical Research-Australian Centre for International and Tropical Health and Nutrition (ACITH), Université de Franche-Comté ( UFC ), Carcinogénèse épithéliale : facteurs prédictifs et pronostiques - UFC ( CEF2P / CARCINO ), Centre Hospitalier Régional Universitaire [Besançon] ( CHRU Besançon ) -Université Bourgogne Franche-Comté ( UBFC ) -Université de Franche-Comté ( UFC ), Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Université de Franche-Comté ( UFC ) -Centre National de la Recherche Scientifique ( CNRS ), Brain imaging ( LIAMA ), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées ( LIAMA ), Centre de Coopération Internationale en Recherche Agronomique pour le Développement ( CIRAD ) -Institut National de la Recherche Agronomique ( INRA ) -Chinese Academy of Sciences [Changchun Branch] ( CAS ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique ( CNRS ) -Centre de Coopération Internationale en Recherche Agronomique pour le Développement ( CIRAD ) -Institut National de la Recherche Agronomique ( INRA ) -Chinese Academy of Sciences [Changchun Branch] ( CAS ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique ( CNRS ), Queensland Institute of Medical Research-University of Queensland [Brisbane]-Australian Centre for International and Tropical Health and Nutrition ( ACITH ), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre Hospitalier Régional Universitaire de Besançon (CHRU Besançon), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Carcinogénèse épithéliale : facteurs prédictifs et pronostiques - UFC (UR 3181) (CEF2P / CARCINO), Centre Hospitalier Régional Universitaire de Besançon (CHRU Besançon)-Université de Franche-Comté (UFC), Laboratoire Chrono-environnement (UMR 6249) (LCE), and Queensland Institute of Medical Research-University of Queensland [Brisbane]-Australian Centre for International and Tropical Health and Nutrition (ACITH)
Subjects: Male, Cost effectiveness, MESH : Aged, MESH: Hospitalization, MESH : Child, Preschool, MESH : Echinococcosis, MESH: Epidemiologic Methods, MESH: Length of Stay, 030308 mycology & parasitology, 0302 clinical medicine, MESH: Aged, 80 and over, MESH : Child, MESH: Child, Epidemiology, 80 and over, MESH : Population Surveillance, MESH : Socioeconomic Factors, MESH : Female, Child, Echinococcus granulosus, MESH: Echinococcosis, Pulmonary, MESH: Treatment Outcome, Aged, 80 and over, MESH: Aged, 0303 health sciences, MESH: Middle Aged, biology, Mortality rate, MESH : Infant, [ SDV.SPEE ] Life Sciences [q-bio]/Santé publique et épidémiologie, Pulmonary, Health Care Costs, Middle Aged, MESH : Adult, Echinococcosis, MESH: Infant, MESH: China, 3. Good health, Hospitalization, MESH : Length of Stay, Treatment Outcome, Infectious Diseases, Child, Preschool, Population Surveillance, MESH : Hospitalization, Female, Public Health, MESH: Public Health, MESH : Health Care Costs, Adult, MESH : Echinococcosis, Pulmonary, China, medicine.medical_specialty, MESH: Socioeconomic Factors, Echinococcosis, Pulmonary, Adolescent, MESH : Male, 030231 tropical medicine, MESH : Public Health, MESH: Health Care Costs, MESH : Treatment Outcome, Echinococcus multilocularis, MESH : Epidemiologic Methods, MESH: Population Surveillance, 03 medical and health sciences, MESH: Echinococcosis, MESH : Adolescent, medicine, Humans, MESH : China, MESH : Middle Aged, Preschool, MESH : Aged, 80 and over, Disease burden, Aged, MESH: Adolescent, MESH: Humans, business.industry, Public health, MESH : Humans, MESH: Child, Preschool, Public Health, Environmental and Occupational Health, Infant, MESH: Adult, Length of Stay, biology.organism_classification, medicine.disease, MESH: Male, Surgery, Socioeconomic Factors, Parasitology, [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie, Epidemiologic Methods, business, MESH: Female, Demography
Abstract: International audience; A comprehensive study of human echinococcosis (caused by Echinococcus granulosus or E. multilocularis), including assessment of hospital records, community surveys and patient follow-up, was conducted in Ningxia Hui Autonomous Region (NHAR), China. In contrast to hospital records that showed 96% of echinococcosis cases were caused by cystic echinococcosis (CE), 56% of cases detected in active community surveys were caused by alveolar echinococcosis (AE). The AE and CE cases co-existed frequently in the same village, even occurring in the same patient. A serious public health problem caused by echinococcosis was evident in southern NHAR, typified by: a long diagnostic history for both AE and CE (7.5 years) compared with a shorter treatment history (4.7 years); a significant mortality rate (39%) caused by AE in one surveyed village, where patients had no previous access to treatment; family aggregation of CE and AE cases; a high proportion of both AE (62.5%) and CE (58%) in females; a high rate of recurrent surgery (30%) for CE demonstrated by surgical records; and frequent symptomatic recurrences (51%) because of discontinuous or sporadic access to chemotherapy for AE. The disease burden for both human AE and CE is thus very severe among these rural communities in NHAR, and this study provides the first attempt to determine the costs of morbidity and surgical intervention of human CE and AE cases both at the hospital and community level in this setting. This information may be useful for assessing the cost effectiveness of designing effective public health programs to control echinococcosis in this and other endemic areas in China and elsewhere.
Published: 2006

2. Stabilities of Negative Correlations between Blood Oxygen Level-Dependent Signals Associated with Sensory and Motor Cortices

Author: Yong He, Tao Jiang, Lixia Tian, Tianzi Jiang, Meng Liang, Xiaobo Li, Bingli Cao, Kun Wang, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Economie de la Production et de l'Intégration Internationale (LEPII), Université Pierre Mendès France - Grenoble 2 (UPMF)-Centre National de la Recherche Scientifique (CNRS), Centre des Sciences du Goût (CSG), Etablissement National d'Enseignement Supérieur Agronomique de Dijon (ENESAD)-Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Centre des Sciences du Goût et de l'Alimentation [Dijon] (CSGA), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF), Centre National de la Recherche Scientifique (CNRS)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), Brain imaging ( LIAMA ), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées ( LIAMA ), Centre de Coopération Internationale en Recherche Agronomique pour le Développement ( CIRAD ) -Institut National de la Recherche Agronomique ( INRA ) -Chinese Academy of Sciences [Changchun Branch] ( CAS ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique ( CNRS ) -Centre de Coopération Internationale en Recherche Agronomique pour le Développement ( CIRAD ) -Institut National de la Recherche Agronomique ( INRA ) -Chinese Academy of Sciences [Changchun Branch] ( CAS ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Economie de la Production et de l'Intégration Internationale ( LEPII ), Université Pierre Mendès France - Grenoble 2 ( UPMF ) -Centre National de la Recherche Scientifique ( CNRS ), Centre des Sciences du Goût et de l'Alimentation [Dijon] ( CSGA ), and Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique ( CNRS )
Subjects: Adult, Male, task-background, Rest, Statistics as Topic, Sensory system, positive correlation, Auditory cortex, Brain mapping, 050105 experimental psychology, Functional Laterality, 03 medical and health sciences, 0302 clinical medicine, Physical Stimulation, Image Processing, Computer-Assisted, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, 0501 psychology and cognitive sciences, Radiology, Nuclear Medicine and imaging, resting state, Research Articles, Visual Cortex, Auditory Cortex, Brain Mapping, Blood-oxygen-level dependent, [ INFO.INFO-IM ] Computer Science [cs]/Medical Imaging, Radiological and Ultrasound Technology, Resting state fMRI, 05 social sciences, functional connectivity, Motor Cortex, Magnetic Resonance Imaging, Oxygen, Brain region, Noise, Neurology, Female, Neurology (clinical), Anatomy, Negative correlation, Psychology, Neuroscience, 030217 neurology & neurosurgery
Abstract: Compared with positive correlations, negative correlations of blood oxygen level‐dependent (BOLD) signals (NCOBSs) have been much less studied. In most related studies, the NCOBSs have been accepted as stable without further consideration. To investigate the stabilities of NCOBSs associated with the auditory, motor, and visual cortices, we evaluated the negative correlation maps of each brain region under different “task‐backgrounds” within the same subject‐group, as well as within different subject‐groups during a conscious resting state. These “task‐backgrounds” refer to tasks not expected to activate the specific ROI under consideration and are in some sense analogous to “resting states.” We found that the negative correlation maps of the motor and visual cortices were quite variable between either different task‐backgrounds or different subject‐groups, whereas those of the auditory cortex exhibited some similarities. These results indicate that the NCOBSs associated with the motor and visual cortices were unstable both under task‐backgrounds and during the conscious resting state. The auditory cortex tended to have stable NCOBSs during these “resting states” (but scanner noise could make the auditory cortex “less resting”). This study highlights the importance of paying attention to the influence of the stabilities of NCOBSs in related studies and establishes the need for further studies on NCOBSs. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.
Published: 2006

3. Numerical study of HCl and SO2 impact on sodium emissions in pulverized-coal flames

Author: Pascale Domingo, Zhihua Wang, Luc Vervisch, Yingzu Liu, Yong He, Yu Lv, Jun Xia, Kefa Cen, Kaidi Wan, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Zhejiang University, Brunel University London [Uxbridge], Mississippi State University [Mississippi], Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), This work was jointly supported by the National Natural Science Foundation of China(51706200), the China Postdoctoral Science Foundation (2018M632460), the Fundamental Research Funds for the Central Universities (2018FZA4012), the Engineering and Physical Sciences Research Council (EPSRC) and the Royal Society of the UK. Y.L. is funded by the Open Topic Exploration Program of the ZJU CEU laboratory. Special thanks are due to Prof. Peter Glarborg of DTU, who provided us the detailed mechanism of alkali metal species. Computing resources were provided by the National Supercomputer Center in Tianjin, China (http://www.nscc-tj.cn)., Sodium chemistry, National Natural Science Foundation of China (51706200), the China Postdoctoral Science Foundation (2018M632460), the Fundamental Research Funds for the Central Universities (2018FZA4012), the Engineering and Physical Sciences Research Council (EPSRC) and the Royal Society of the UK, Open Topic Exploration Program of the ZJU CEU laboratory, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), and Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Sodium chemistry, 020209 energy, General Chemical Engineering, Diffusion, Sodium, Energy Engineering and Power Technology, chemistry.chemical_element, SO2, 02 engineering and technology, HCl, Combustion, complex mixtures, 7. Clean energy, Alkali metal, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Corrosion, Emission, 020401 chemical engineering, 0202 electrical engineering, electronic engineering, information engineering, Coal, 0204 chemical engineering, HCI, Fouling, Pulverized coal-fired boiler, business.industry, Organic Chemistry, Fuel Technology, chemistry, Chemical engineering, 13. Climate action, Pulverized-coal combustion, business
Abstract: International audience; Sodium emissions during pulverized-coal combustion (PCC) are known to result in severeash-related operating issues of coal furnaces, e.g., fouling, slagging and corrosion. To relieve these issues and advance the clean utilization technologies of coal, a better understanding of thefundamental mechanisms driving the formation and transformation of the sodium species is required.In the present study, sodium emissions have been simulated in both one-dimensional (1D) premixed/diffusion flames of the coal volatile and an early-stage two-dimensional (2D)pulverized-coal flame. The properties of Loy Yang brown coal are used. The DRM22 skeletal mechanism is employed for volatile-gas combustion, and the reaction of sodium species is modeled by a detailed mechanism encompassing the elements Na, C, H, O, S and Cl. The compositions of the volatile fuels are obtained from the chemical percolation devolatilization (CPD) model, including CH4, C2H2, CO, H2, CO2 and H2O. The initial species of Na, Cl and S in the volatile gas is set to be NaOH, HCl and SO2, respectively. The transformation characteristics of 12 sodium species are investigated in both the 1D volatile flames and the 2D pulverized-coal flame. The response of the sodium chemistry to volatile-gas combustion is analyzed under fuel-lean, stoichiometric and fuel-rich conditions. Na, NaOH and NaCl are found to be the major sodium species during the combustion. Parametric studies with HCl, SO2 or both species removed from the volatile are then performed to investigate their effects on the sodium transformation characteristics in both the 1D and 2D flames. The results show that HCl has a much stronger ability to react with sodium species than SO2.
Published: 2019

4. Le paradoxe de l’invisibilité d’une minorité visible : immigrés et descendants d’immigrés chinois en France

Author: Juan Du, Florence Lévy, Hélène Le Bail, Zhipeng Li, Héritages : Culture(s), Patrimoine(s), Création(s) (Héritages - UMR 9022), Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)-CY Cergy Paris Université (CY), Tsinghua University [Beijing] (THU), Centre de recherches internationales (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Unite de recherche migrations et sociétés (URMIS), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205-Centre National de la Recherche Scientifique (CNRS), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Opto-electronic Engineering, Beijing Institute of Technology (BIT), Kansas State University, Key Laboratory of Horticultural Plant Biology, Huazhong Agricultural University, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL), Centre de recherches internationales (Sciences Po, CNRS) (CERI), Université Nice Sophia Antipolis (1965 - 2019) (UNS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Huazhong Agricultural University [Wuhan] (HZAU), École normale supérieure - Paris (ENS-PSL), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205
Subjects: Chinois, [SHS.SOCIO]Humanities and Social Sciences/Sociology, représentation de l'immigré, [SHS.DEMO]Humanities and Social Sciences/Demography, [SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology, Île-de-France, stéréotype, [SHS.SCIPO]Humanities and Social Sciences/Political science, minorité, 8. Economic growth, espace urbain, France, Marseille, ComputingMilieux_MISCELLANEOUS
Abstract: Ce dossier vise a questionner le paradoxe de la visibilite et de l’invisibilite des migrants chinois et de leurs descendants en France. Si la visibilite de la population issue de l’immigration chinoise en France ne peut etre niee dans le paysage urbain de certains quartiers de concentration commerciale, entrepreneuriale ou de residence, ou lors d’evenements culturels comme les defiles du Nouvel An lunaire, on parle pourtant souvent de « minorite invisible » ou « discrete ». Cela fait moins reference a son imperceptibilite dans la ville que, d'une part, a une forme d'invisibilite de l'histoire et de la diversite de cette population, et, d'autre part, a sa marginalite sociale et politique. Dans quelle mesure les perceptions exterieures et les lieux communs assignent-ils ces personnes d’origine chinoise a des formes de visibilite et d’invisibilite ? Jusqu’a quel point les processus de visibilisation et d’invisibilisation resultent-ils de strategies volontaires de la part de ces migrants et de leurs descendants ? C’est pour avancer sur ces questions que ce dossier rassemble les travaux issus de terrains de recherche emergents, en particulier ceux realises par de jeunes chercheurs ou des acteurs de la societe civile. Les articles publies sont le fruit de trois ans d’un travail collectif realise dans le cadre du projet « Chinois.es en Ile-de-France » finance par la Ville de Paris.
Published: 2021

5. Chinois en France : visibles, invisibles ?

Author: Du, Juan, Le Bail, Hélène, Lévy, Florence, Zhipeng, Li, Tsinghua University [Beijing] (THU), Centre de recherches internationales (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Unite de recherche migrations et sociétés (URMIS), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205-Centre National de la Recherche Scientifique (CNRS), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Opto-electronic Engineering, Beijing Institute of Technology (BIT), Kansas State University, Key Laboratory of Horticultural Plant Biology, Huazhong Agricultural University, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL), Juan Du, Hélène Le Bail, Florence Lévy, Li Zhipeng, Centre de recherches internationales (Sciences Po, CNRS) (CERI), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205, and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: Chinois, [SHS.SOCIO]Humanities and Social Sciences/Sociology, minorité, représentation de l'immigré, espace urbain, France, [SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology, Île-de-France, Marseille, stéréotype, [SHS.SCIPO]Humanities and Social Sciences/Political science
Abstract: Ce dossier vise à questionner le paradoxe de la visibilité et de l’invisibilité des migrants chinois et de leurs descendants en France. Si la visibilité de la population issue de l’immigration chinoise en France ne peut être niée dans le paysage urbain de certains quartiers de concentration commerciale, entrepreneuriale ou de résidence, ou lors d’évènements culturels comme les défilés du Nouvel An lunaire, on parle pourtant souvent de « minorité invisible » ou « discrète ». Cela fait moins référence à son imperceptibilité dans la ville que, d'une part, à une forme d'invisibilité de l'histoire et de la diversité de cette population, et, d'autre part, à sa marginalité sociale et politique. Dans quelle mesure les perceptions extérieures et les lieux communs assignent-ils ces personnes d’origine chinoise à des formes de visibilité et d’invisibilité ? Jusqu’à quel point les processus de visibilisation et d’invisibilisation résultent-ils de stratégies volontaires de la part de ces migrants et de leurs descendants ? C’est pour avancer sur ces questions que ce dossier rassemble les travaux issus de terrains de recherche émergents, en particulier ceux réalisés par de jeunes chercheurs ou des acteurs de la société civile. Les articles publiés sont le fruit de trois ans d’un travail collectif réalisé dans le cadre du projet « Chinois.es en Île-de-France » financé par la Ville de Paris.
Published: 2021

6. L’accès au logement par Dapu. Les pratiques de logement des immigrés chinois en banlieue parisienne

Author: Du, Juan, Centre de recherches internationales (Sciences Po, CNRS) (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Tsinghua University [Beijing] (THU), Unite de recherche migrations et sociétés (URMIS), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Opto-electronic Engineering, Beijing Institute of Technology (BIT), Kansas State University, Key Laboratory of Horticultural Plant Biology, Huazhong Agricultural University, Ya-Han Chuang, Anne-Christine Trémon, Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205-Centre National de la Recherche Scientifique (CNRS), Huazhong Agricultural University [Wuhan] (HZAU), Centre de recherches internationales (CERI), Université Nice Sophia Antipolis (... - 2019) (UNS), and Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SHS.SOCIO]Humanities and Social Sciences/Sociology, immigrés chinois, France, pratique de logement, [SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology
Abstract: Plan du chapitre : - Un accès difficile : la double exclusion ; - Des « quartiers chinois » à l’enquête à La Noue ; - Dapu, terme emic et outil etic ; - Conclusion
Published: 2020

7. Chinese Immigrants Acting as Local Residents: De facto Citizenship in the Banlieues of Paris

Author: Juan Du (杜娟), Laboratoire AGORA (AGORA - EA 7392), CY Cergy Paris Université (CY), Centre de recherches internationales (Sciences Po, CNRS) (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Tsinghua University [Beijing] (THU), Unite de recherche migrations et sociétés (URMIS), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Opto-electronic Engineering, Beijing Institute of Technology (BIT), Kansas State University, Key Laboratory of Horticultural Plant Biology, Huazhong Agricultural University, Du, Juan, Centre de recherches internationales (CERI), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Paris Diderot - Paris 7 (UPD7)-Institut de recherche pour le développement [IRD] : UR205-Centre National de la Recherche Scientifique (CNRS), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and Huazhong Agricultural University [Wuhan] (HZAU)
Subjects: Cultural Studies, De facto, Sociology and Political Science, [SHS.SOCIO] Humanities and Social Sciences/Sociology, media_common.quotation_subject, Immigration, 0507 social and economic geography, collective actions, [SHS.DEMO]Humanities and Social Sciences/Demography, Chinese residents, Political science, 050602 political science & public administration, China, Citizenship, everyday resistance, ComputingMilieux_MISCELLANEOUS, media_common, urban violence, [SHS.ANTHRO-SE] Humanities and Social Sciences/Social Anthropology and ethnology, [SHS.SOCIO]Humanities and Social Sciences/Sociology, [SHS.DEMO] Humanities and Social Sciences/Demography, History of China, Chinese migrants, 05 social sciences, Gender studies, [SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology, de facto citizenship, [SHS.SCIPO]Humanities and Social Sciences/Political science, 0506 political science, Asian studies, Metadata, Work (electrical), Anthropology, 050703 geography
Abstract: Urban violence and threats to personal safety are everyday issues of shared concern for Chinese migrants in France. They push Chinese migrants to act as local residents and to interact with the host country in various and unexpected ways, whether openly or inconspicuously, in order to improve their living environment and negotiate their place in the host society. Drawing on an ethnography of Chinese immigrants living in the banlieues of Paris and their everyday social practices in relation to the issues of violence and insecurity, this article documents the strategies of everyday resistance used by Chinese immigrants, grounded in their local knowledge. In a shift toward further local participation, they perform these actions as local residents, resulting in a de facto citizenship.
Published: 2020

8. Numerical study of HCl and SO2 impact on potassium emissions in pulverized-biomass combustion

Author: Pascale Domingo, Luc Vervisch, Jun Xia, Kaidi Wan, Yong He, Zhihua Wang, Yu Lv, Yingzu Liu, Kefa Cen, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Zhejiang University, Brunel University London [Uxbridge], Mississippi State University [Mississippi], Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), This work was jointly supported by the National Natural Science Foundation of China (51706200), the China Postdoctoral Science Foundation (2018M632460), the Fundamental Research Funds for the Central Universities (2018FZA4012), the Engineering and Physical Sciences Research Council (EPSRC) and the Royal Society of the UK. The first author K.D.W. would like to acknowledge the support from the Centre national de la recherche scientifique (CNRS) of the France. Y.L. is funded by the Open Topic Exploration Program of the ZJU CEU laboratory. Special thanks are due to Prof. Peter Glarborg of DTU, who provided us the detailed mechanism of alkali metal species. Computing resources were provided by the National Supercomputer Center in Tianjin, China (http://www.nscc-tj.cn) ., Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 020209 energy, General Chemical Engineering, Diffusion, Potassium, Energy Engineering and Power Technology, Biomass, chemistry.chemical_element, SO2, 02 engineering and technology, Alkali metal, potassium chemistry, Combustion, HCl, 7. Clean energy, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Emission, 020401 chemical engineering, emission, 0202 electrical engineering, electronic engineering, information engineering, pulverized-biomass combustion, Deposition (phase transition), Pulverized-biomass combustion, alkali metal, 0204 chemical engineering, Potassium chemistry, HCI, Fouling, Chemistry, Fuel Technology, Environmental chemistry, Stoichiometry
Abstract: International audience; The potassium vapor released during the combustion of biomass are known to result in serious ash deposition, fouling and corrosion issues of biomass furnaces. To develop potassium control technologies to mitigate these issues and achieve clean utilization of biomass fuel, a better understanding of the fundamental formation and transformation mechanisms of potassium in biomass combustion is essentially required. In the present study, potassium emissions during pulverized-biomass combustion, for the first time, have been simulated in both one-dimensional (1D) premixed/diffusion flames of the biomass volatile and an early-stage two-dimensional (2D) pulverized-biomass flame. The properties of corn straw are used. The volatile-gas combustion is described by the DRM22 skeletal mechanism, while the homogeneous reaction of potassium species is modeled using a detailed mechanism encompassing the elements K, C, H, O, Cl and S. The initial species of K, Cl and S in the volatile gas is set to be KOH, HCl and SO2, respectively. The transformation characteristics of the potassium species are numerically investigated in both the 1D and 2D flames. Results show that KOH is the most significant potassium product under fuel-lean, stoichiometric and fuel-rich conditions, while the productions of sulfurous and chloric potassium species are secondary. Parametric studies with HCl, SO2 or both species replaced with N2 in volatile gas are then performed to study their impacts on potassium emission characteristics in both the 1D and 2D flames. The results indicate that HCl has a stronger ability to react with potassium species than SO2.
Published: 2019

9. Measurement and kinetics of elemental and atomic potassium release from a burning biomass pellet

Author: Hamid Bahai, Kefa Cen, Jun Xia, Kaidi Wan, Zhihua Wang, Yingzu Liu, Luc Vervisch, Ronald Whiddon, Yong He, Zhejiang University, Taiyuan University of Technology, Brunel University London [Uxbridge], Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), This work was supported by the National Natural Science Foundation of China (51776185) and the Program of Introducing Talents of Discipline to University (B08026). Financial support from the Royal Society and the Engineering and Physical Sciences Research Council (EPSRC) of the UK is also gratefully acknowledged., Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université de Rouen Normandie (UNIROUEN), and Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 020209 energy, General Chemical Engineering, Potassium, Inorganic chemistry, Biomass, chemistry.chemical_element, 02 engineering and technology, Combustion, 7. Clean energy, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 020401 chemical engineering, PLIF, Pellet, 0202 electrical engineering, electronic engineering, information engineering, Char, 0204 chemical engineering, Physical and Theoretical Chemistry, Chemistry, Mechanical Engineering, food and beverages, Straw, Decomposition, Kinetics, 13. Climate action, Multi-point LIBS, Mechanism, Pyrolysis
Abstract: International audience; Combining polarizing-filtered planar laser-induced fluorescence (PLIF) with simultaneous laser absorption, quantitative laser-induced breakdown spectroscopy (LIBS) and two-color pyrometry, the potassium release during the combustion of biomass fuels (corn straw and poplar) has been investigated. The temporal release profiles of volatile atomic potassium and potassium compounds from a corn straw show a single peak. The woody biomass, poplar, produces a dual-maxima distribution for potassium and potassium compounds. For both biomass samples, the highest concentrations of released atomic potassium and potassium compounds occur in the devolatilization stage. The mass ratios between volatile atomic potassium and potassium compounds in the corn straw and poplar cases are 0.77% and 0.79%, respectively. These values agree well with chemical equilibrium predictions that 0.68% of total potassium will be in atomic form. A two-step kinetic model of potassium release has been developed, which gives better predictions during the devolatilization stage than the existing single-step model. Finally, a map of potassium transformation processes during combustion is developed. Starting with inorganic and organic potassium, there are eight proposed transformation pathways including five proposed release pathways that occur during the combustion. The pathways describe the transformation of potassium between the fuel volatile matter, char, and ash. Potassium release during the devolatilization stage is due to pyrolysis and evaporation; during the char burnout stage, potassium release is due to char oxidation and decomposition; and during the ash cooking stage, potassium release is caused by reactions between the ash and H2O in the co-flow.
Published: 2019

10. Vocabulary growth rate from preschool to school-age years is reflected in the connectivity of the arcuate fasciculus in 14-year-old children

Author: Jingjing Zhao, Catherine McBride, Franck Ramus, Michel Thiebaut de Schotten, Shuang Song, Hua Shu, Wei Zhou, Gaolang Gong, Mengmeng Su, Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of psychiatry-King‘s College London, Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Shandong Normal University, Institute of Computing Technology, Chinese Academy of Sciences [Beijing] (CAS), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Laboratoire de sciences cognitives et psycholinguistique (LSCP), Département d'Etudes Cognitives - ENS Paris (DEC), École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École des hautes études en sciences sociales (EHESS), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), Shaanxi Normal University (SNNU), École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL)
Subjects: Male, Longitudinal study, Vocabulary, medicine.medical_specialty, Adolescent, Cognitive Neuroscience, media_common.quotation_subject, Audiology, Brain mapping, Language Development, behavioral disciplines and activities, 050105 experimental psychology, 03 medical and health sciences, 0302 clinical medicine, Child Development, Fractional anisotropy, Developmental and Educational Psychology, medicine, Arcuate fasciculus, Humans, 0501 psychology and cognitive sciences, Longitudinal Studies, Child, media_common, Language, Brain Mapping, 05 social sciences, [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, Verbal Learning, White Matter, Vocabulary development, Language development, medicine.anatomical_structure, Diffusion Tensor Imaging, nervous system, Child, Preschool, Anisotropy, Female, Nerve Net, Psychology, 030217 neurology & neurosurgery, Tractography
Abstract: International audience; The acquisition of language involves the functional specialization of several cortical regions. Connectivity between these brain regions may also change with the development of language. Various studies have demonstrated that the arcuate fasciculus was essential for language function. Vocabulary learning is one of the most important skills in language acquisition. In the present longitudinal study, we explored the influence of vocabulary development on the anatomical properties of the arcuate fasciculus. Seventy-nine Chinese children participated in this study. Between age 4 and age 10, they were administered the same vocabulary task repeatedly. Following a previous study, children's vocabulary developmental trajectories were clustered into three subgroups (consistently good, catch-up, consistently poor). At age 14, diffusion tensor imaging data were collected. Using ROI-based tractography, the anterior, posterior and direct segments of the bilateral arcuate fasciculus were delineated in each child's native space. Group comparisons showed a significantly reduced fractional anisotropy in the left arcuate fasciculus of children in the consistently poor group, in particular in the posterior and direct segments of the arcuate fasciculus. No group differences were observed in the right hemisphere, nor in the left anterior segment. Further regression analyses showed that the rate of vocabulary development, rather than the initial vocabulary size, was a specific predictor of the left arcuate fasciculus connectivity.; http://www.lscp.net/persons/ramus/docs/DS18.pdf
Published: 2018

11. Alterations in white matter pathways underlying phonological and morphological processing in Chinese developmental dyslexia

Author: Michel Thiebaut de Schotten, Jingjing Zhao, Gaolang Gong, Hua Shu, Mengmeng Su, Wei Zhou, Franck Ramus, Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of psychiatry-King‘s College London, Institute of Computing Technology, Chinese Academy of Sciences [Beijing] (CAS), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de sciences cognitives et psycholinguistique (LSCP), Département d'Etudes Cognitives - ENS Paris (DEC), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École des hautes études en sciences sociales (EHESS), Shaanxi Normal University (SNNU), École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL)
Subjects: Male, Morphology, Cognitive Neuroscience, Phonology, behavioral disciplines and activities, 050105 experimental psychology, White matter, Dyslexia, 03 medical and health sciences, 0302 clinical medicine, Asian People, Fractional anisotropy, Fasciculus, medicine, Arcuate fasciculus, Humans, 0501 psychology and cognitive sciences, Inferior longitudinal fasciculus, 10. No inequality, Child, Original Research, Chinese, biology, 05 social sciences, lcsh:QP351-495, [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, biology.organism_classification, medicine.disease, White Matter, Semantics, medicine.anatomical_structure, Diffusion Tensor Imaging, lcsh:Neurophysiology and neuropsychology, Writing system, Reading, White matter pathway, Anisotropy, Female, Psychology, Neuroscience, Tractography, 030217 neurology & neurosurgery
Abstract: International audience; Chinese is a logographic language that is different from alphabetic languages in visual and semantic complexity. Thus far, it is still unclear whether Chinese children with dyslexia show similar disruption of white matter pathways as in alphabetic languages. The present study focused on the alteration of white matter pathways in Chinese children with dyslexia. Using diffusion tensor imaging tractography, the bilateral arcuate fasciculus (AF-anterior, AF-posterior and AF-direct segments), inferior fronto-occipital fasciculus (IFOF) and inferior longitudinal fasciculus (ILF) were delineated in each individual's native space. Compared with age-matched controls, Chinese children with dyslexia showed reduced fractional anisotropy in the left AF-direct and the left ILF. Further regression analyses revealed a functional dissociation between the left AF-direct and the left ILF. The AF-direct tract integrity was associated with phonological processing skill, an ability important for reading in all writing systems, while the ILF integrity was associated with morphological processing skill, an ability more strongly recruited for Chinese reading. In conclusion, the double disruption locus in Chinese children with dyslexia, and the functional dissociation between dorsal and ventral pathways reflect both universal and specific properties of reading in Chinese.
Published: 2018

12. The effect of body–mind relaxation meditation induction on major depressive disorder: A resting-state fMRI study

Author: Xiaoling Wang, Jing Sui, Wei-dong Wang, Tianzi Jiang, Xueyu Lv, Tao Li, Jiliang Fang, Lingzhong Fan, Fangfang Chen, Shan Yu, Yang Hong, University of Science & Technology of China [Suzhou], China Academy of Chinese Medical Sciences, Columbia University [New York], Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: Adult, Male, Psychotherapist, Brain activity and meditation, Rest, media_common.quotation_subject, Prefrontal Cortex, Cognitive reappraisal, [SCCO]Cognitive science, medicine, Humans, Meditation, Depression (differential diagnoses), media_common, Brain Mapping, Depressive Disorder, Major, Relaxation (psychology), Resting state fMRI, Middle Aged, medicine.disease, Magnetic Resonance Imaging, Frontal Lobe, Psychiatry and Mental health, Clinical Psychology, Major depressive disorder, Female, Orbitofrontal cortex, Psychology, Neuroscience
Abstract: International audience; Background: Meditation has been increasingly evaluated as an important complementary therapeutic tool for the treatment of depression. The present study employed resting state functional magnetic resonance imaging (rs-fMRI) to examine the effect of body mind relaxation meditation induction (BMRMI) on the brain activity of depressed patients and to investigate possible mechanisms of action for this complex intervention.Method: 21 major depressive disorder patients (MDDs) and 24 age and gender-matched healthy controls (HCs) received rs-fMRI scans at baseline and after listening to a selection of audio designed to induce body-mind relaxation meditation. The rs-fMRI data were analyzed using Matlab toolbox to obtain the amplitude of low-frequency fluctuations (ALFF) of the BOLD signal for the whole brain. A mixed-design repeated measures analysis of variance (ANOVA) was performed On the whole brain to Find which brain regions were affected by the BMRMI An additional functional connectivity analysis was used to identify any atypical connection patterns after the BMRMI.Results: After the BMRMI experience, both the MDDs and HCs showed decreased ALFF values in the bilateral frontal pole (BA10). Additionally, increased functional connectivity from the right dorsal medial prefrontal cortex (dmPFC) to the left dorsal lateral prefrontal cortex (dlPFC) and the left lateral orbitofrontal cortex (OFC) was identified only in the MDDs after the BMRMI. Limitation: in order to exclude the impact of other events on the participants brain activity. the Hamilton Rating Scales for Depression (HDRS) was not measured after the body-mind relaxation induction.Conclusion: Our findings support the hypothesis that body-mind relaxation meditation induction may regulate the activities of the prefrontal cortex and thus may have the potential to help patients construct reappraisal strategies that can modulate the brain activity in multiple emotion-processing systems.
Published: 2015

13. Aiming strategy optimization for uniform flux distribution in the receiver of a linear Fresnel solar reflector using a multi-objective genetic algorithm

Author: Yu Qiu, Xiaodai Xue, Kun Wang, Ming-Jia Li, Zhan-Bin Liu, Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education, Xi'an Jiaotong University (Xjtu), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Tsinghua University [Beijing], Tsinghua University [Beijing] (THU), and Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Work (thermodynamics), 020209 energy, Linear Fresnel solar reflector, [PHYS.MECA.GEME]Physics [physics]/Mechanics [physics]/Mechanical engineering [physics.class-ph], Reflector (antenna), 02 engineering and technology, Management, Monitoring, Policy and Law, Optics, Flux (metallurgy), Control theory, Genetic algorithm, 0202 electrical engineering, electronic engineering, information engineering, Aiming strategy optimization, Flux distribution, business.industry, Mechanical Engineering, Drop (liquid), Flux distribution non-uniformity, Monte Carlo ray tracing, Percentage point, Optical loss, Building and Construction, 021001 nanoscience & nanotechnology, General Energy, Multi-objective genetic algorithm, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, Distributed ray tracing
Abstract: International audience; Non-uniform solar flux may lead to negative effects in the receiver of the linear Fresnel reflector (LFR), including the failure of the receiver and the fluctuating operation. For reducing these effects, an aiming strategy optimization approach is presented by combining a multi-objective Genetic Algorithm (GA) and Monte Carlo ray tracing to homogenize the flux distribution in current work. Both the flux non-uniformity index and the optical loss (ηloss) are used as the objective functions. Based on the approach, first, the flux distributions in the Multi-Tube Cavity Receiver (MTCR) and the Single-Tube Receiver with a Secondary Collector (STRSC) are optimized at a typical condition. Optimal results indicate that the GA optimization strategy (S2) can reach a compromise between the flux non-uniformity and the optical loss in both MTCR and STRSC systems. Furthermore, the optimal strategy obtained at a specific transversal incidence angle can be applied in a relatively large range around it. Moreover, parameter study indicates that the aiming line number (naim) has little impact on the efficiencies of the two systems. naim has almost no effect on the flux non-uniformity in the MTCR, but the effect is visible in the STRSC. Finally, the application of S2 under a real-time condition indicates that fluxes in the two receivers can be homogenized efficaciously in the whole time range with a small drop of 0.2–3.8 percentage points in efficiency compared with those of traditional one-line aiming strategy (S1). It is also found that the flux non-uniformity indexes of the MTCR are greatly reduced from 0.77–1.09 to 0.02–0.06 when S1 is replaced by S2, and those of the STRSC are steeply reduced from 0.59–0.70 to 0.29–0.37. It is concluded that the present approach is effective and suitable for homogenizing the fluxes in the receivers of LFRs.
Published: 2017

14. Exploring links between pH and bacterial community composition in soils from the Craibstone Experimental Farm

Author: Xingpeng Jiang, Andre P. Masella, Michael D. Lynch, Andrea K. Bartram, Josh D. Neufeld, Graeme W. Nicol, Jonathan Dushoff, Department of Biology []Waterloo], University of Waterloo [Waterloo], Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Ampère, Département Bioingénierie (BioIng), Ampère (AMPERE), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), McMaster University [Hamilton, Ontario], This research was supported by a Discovery Grant from the Natural Sciences and Engineering Research Council of Canada (NSERC), Ampère, Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Operational taxonomic unit, Rare biosphere, Molecular Sequence Data, Polymerase Chain Reaction, Applied Microbiology and Biotechnology, Microbiology, Soil, [SPI]Engineering Sciences [physics], RNA, Ribosomal, 16S, Soil pH, Gammaproteobacteria, Botany, rare biosphere, Soil Microbiology, agriculture, Bacteria, Ecology, biology, Denaturing Gradient Gel Electrophoresis, pH, soil bacteria, Verrucomicrobia, Genes, rRNA, Sequence Analysis, DNA, Hydrogen-Ion Concentration, biology.organism_classification, RNA, Bacterial, UniFrac, 16S rRNA genes, Scotland, Genes, Bacterial, microbial diversity, [SDE]Environmental Sciences, Temperature gradient gel electrophoresis, Acidobacteria
Abstract: International audience; Soil pH is an important determinant of microbial community composition and diversity, yet few studies have characterized the specific effects of pH on individual bacterial taxa within bacterial communities, both abundant and rare. We collected composite soil samples over 2 years from an experimentally maintained pH gradient ranging from 4.5 to 7.5 from the Craibstone Experimental Farm (Craibstone, Scotland). Extracted nucleic acids were characterized by bacterial and group-specific denaturing gradient gel electrophoresis and next-generation sequencing of bacterial 16S rRNA genes. Both methods demonstrated comparable and reproducible shifts within higher taxonomic bacterial groups (e.g. Acidobacteria,Alphaproteobacteria,Verrucomicrobia, and Gammaproteobacteria) across the pH gradient. In addition, we used non-negative matrix factorization (NMF) for the first time on 16S rRNA gene data to identify positively interacting (i.e. co-occurring) operational taxonomic unit (OTU) clusters (i.e. ‘components’), with abundances that correlated strongly with pH, and sample year to a lesser extent. All OTUs identified by NMF were visualized within principle coordinate analyses of UNIFRAC distances and subjected to taxonomic network analysis (SSUnique), which plotted OTU abundance and similarity against established taxonomies. Most pH-dependent OTUs identified here would not have been identified by previous methodologies for microbial community profiling and were unrelated to known lineages.
Published: 2013

15. Single-shot diffraction data from the Mimivirus particle using an X-ray free-electron laser

Author: Christoph Bostedt, Marc Messerschmidt, Anton Barty, M. Marvin Seibert, Christina Y. Hampton, Henry N. Chapman, Jakob Andreasson, N. Duane Loh, Michael J. Bogan, Sebastian Schorb, Dusko Odic, Holger Fleckenstein, Nicola Coppola, Benjamin Erk, Bianca Iwan, Robert L. Shoeman, Meng Liang, Georg Weidenspointner, Stephan Kassemeyer, Raymond G. Sierra, Christian Reich, Tomas Ekeberg, Lars Gumprecht, Günter Hauser, Ilme Schlichting, Faton Krasniqi, Janos Hajdu, Carlo Schmidt, Filipe R. N. C. Maia, Sascha W. Epp, Olof Jönsson, Lothar Strüder, Miriam Barthelmess, Inger Andersson, Andrew V. Martin, Benedikt Rudek, Cornelia B. Wunderer, Nils Kimmel, Martin Svenda, Saša Bajt, John D. Bozek, Virginie Seltzer, Lukas Lomb, Heike Soltau, Daniel Rolles, Matthias Frank, Chantal Abergel, Helmut Hirsemann, Heinz Graafsma, Jacek Krzywinski, Daniel P. DePonte, Daniel Westphal, Joachim Ullrich, Peter Holl, Robert Hartmann, Andreas Hartmann, Artem Rudenko, Andrew Aquila, Jean-Michel Claverie, Lutz Foucar, Department of Cell and Molecular Biology [Uppsala], Uppsala University, Information génomique et structurale (IGS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot - Paris 7 (UPD7), Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory (SLAC), Stanford University-Stanford University, Centre for Quantum Engineering and Space-time Research (QUEST), Leibniz Universität Hannover=Leibniz University Hannover, Department of Molecular Biology, Swedish University of Agricultural Sciences (SLU), Lawrence Livermore National Laboratory (LLNL), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), University of Oxford, Public Medicine Infectious Diseases Section, SUN, Argonne National Laboratory [Lemont] (ANL), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Stanford University, National Science Foundation [Arlington] (NSF), Max Planck Institute for Medical Research [Heidelberg], Max-Planck-Gesellschaft, Deutsches Elektronen-Synchrotron [Hamburg] (DESY), Kansas State University, CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Department of Biomolecular Mechanisms, Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Max-Planck-Institut für Kernphysik (MPIK), Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), DESY, Ctr Free Electron Laser Sci, D-22607 Hamburg, Germany, Department of Cell and Molecular Biology [Sweden] (DCMB), Uppsala University-Medical Nobel Institute, Linac Coherent Light Source, SLAC - National Accelerator Laboratory, Leibniz Universität Hannover [Hannover] (LUH), University of Oxford [Oxford], Stanford Linear Accelerator Center (SLAC), Stanford University [Stanford], Centre de Référence National 'Syndrome Gilles de la Tourette', Pôle des Maladies du Système Nerveux, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique des Hôpitaux de Paris, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), University of California [Berkeley], University of California-University of California, Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: 0301 basic medicine, Data Descriptor, Computer science, Image Processing, 02 engineering and technology, Bioinformatics, law.invention, Imaging, Scattering, Computer-Assisted, Theoretical, X-Ray Diffraction, law, Models, Crystallography, Radiation, biology, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], Data Collection, 3D reconstruction, Free-electron laser, Virus structures, 021001 nanoscience & nanotechnology, Computer Science Applications, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM], Benchmark (computing), Biomedical Imaging, Statistics, Probability and Uncertainty, 0210 nano-technology, Mimiviridae, Algorithms, Information Systems, Statistics and Probability, Atom and Molecular Physics and Optics, Image processing, Electrons, Library and Information Sciences, Education, 03 medical and health sciences, Optics, Imaging, Three-Dimensional, X-rays, Medical imaging, Computer Simulation, ddc:610, Particle Size, Mimivirus, business.industry, X-Rays, Lasers, Laser, biology.organism_classification, 030104 developmental biology, Three-Dimensional, X-Ray, Atom- och molekylfysik och optik, business, Biological physics
Abstract: Scientific data 3, 160060 (2016). doi:10.1038/sdata.2016.60, Free-electron lasers (FEL) hold the potential to revolutionize structural biology by producing X-ray pules short enough to outrun radiation damage, thus allowing imaging of biological samples without the limitation from radiation damage. Thus, a major part of the scientific case for the first FELs was three-dimensional (3D) reconstruction of non-crystalline biological objects. In a recent publication we demonstrated the first 3D reconstruction of a biological object from an X-ray FEL using this technique. The sample was the giant Mimivirus, which is one of the largest known viruses with a diameter of 450 nm. Here we present the dataset used for this successful reconstruction. Data-analysis methods for single-particle imaging at FELs are undergoing heavy development but data collection relies on very limited time available through a highly competitive proposal process. This dataset provides experimental data to the entire community and could boost algorithm development and provide a benchmark dataset for new algorithms., Published by Nature Publ. Group, London
Published: 2016

16. Modélisation de la croissance végétale, les opérateurs de croissance, cas stochastique

Author: de Reffye, Philippe, Kang, Mengzhen, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Département Systèmes Biologiques (Cirad-BIOS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Chinese Academy of Sciences [Changchun Branch] (CAS), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])
Subjects: [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Croissance végétale, Modélisation végétale, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2016

17. Modélisation de la croissance végétale, les opérateurs de croissance, cas stochastique

Author: Zhang, Baogui, Yan, Guo, Heuvelink, Ep, Rey, Hervé, De Reffye, Philippe, Key Laboratory of Plant-Soil Interactions - College of Resources and Environmental Sciences (PSI), China Agricultural University (CAU), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Chinese Academy of Sciences [Changchun Branch] (CAS), Wageningen University and Research Centre [Wageningen] (WUR), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Département Systèmes Biologiques (Cirad-BIOS), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)
Subjects: [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Croissance végétale, Modélisation végétale, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2016

18. Altered functional connectivity in early Alzheimer's disease: A resting-state fMRI study

Author: Lixia Tian, Tianzi Jiang, Kun Wang, Kuncheng Li, Liang Wang, Meng Liang, Xinqing Zhang, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Department of Radiology, Xuanwu Hospital of Capital-University of Medical Sciences / Beijing, and Department of Neurology
Subjects: Male, Neuropsychological Tests, Functional Laterality, Correlation, 0302 clinical medicine, Degenerative disease, Parietal Lobe, Neural Pathways, Image Processing, Computer-Assisted, low-frequency blood oxygenation level-dependent fluctuations, Research Articles, Radiological and Ultrasound Technology, medicine.diagnostic_test, fMRI, 05 social sciences, Parietal lobe, Brain, Alzheimer's disease, Middle Aged, Prognosis, Magnetic Resonance Imaging, Neurology, Disease Progression, Female, Occipital Lobe, Anatomy, Psychology, Prefrontal Cortex, 050105 experimental psychology, Central nervous system disease, 03 medical and health sciences, resting-state, Alzheimer Disease, Predictive Value of Tests, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, medicine, Humans, 0501 psychology and cognitive sciences, Radiology, Nuclear Medicine and imaging, Aged, Resting state fMRI, functional connectivity, medicine.disease, Early Diagnosis, Neurology (clinical), Nerve Net, Cognition Disorders, Occipital lobe, Functional magnetic resonance imaging, Neuroscience, 030217 neurology & neurosurgery
Abstract: Previous studies have led to the proposal that patients with Alzheimer's disease (AD) may have disturbed functional connectivity between different brain regions. Furthermore, recent resting‐state functional magnetic resonance imaging (fMRI) studies have also shown that low‐frequency (
Published: 2007

19. The effect of body–mind relaxation meditation induction on majordepressive disorder: A resting-state fMRI study

Author: Chen, Fangfang, Lv, Xueyu, Fang, Jiliang, Yu, Shan, Sui, Jing, Fan, Lingzhong, Li, Tao, Hong, Yang, Wang, Xiaoling, Wang, weidong, Jiang, Tianzi, University of Science & Technology of China [Suzhou], China Academy of Chinese Medical Sciences, Columbia University [New York], Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SCCO]Cognitive science, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2015

20. Changes in hippocampal connectivity in the early stages of Alzheimer's disease: Evidence from resting state fMRI

Author: Tao Wu, Liang Wang, Yong He, Xinqing Zhang, Meng Liang, Yu-Feng Zang, Kuncheng Li, Lixia Tian, Tianzi Jiang, Department of Radiology, Xuanwu Hospital of Capital-University of Medical Sciences / Beijing, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), National Laboratory of Pattern Recognition [Beijing] (NLPR), Institute of Automation - Chinese Academy of Sciences, Department of Neurology, Institute of Geriatrics, and Xuanwu Hospital of Capital
Subjects: Male, Cognitive Neuroscience, Precuneus, Hippocampus, Hippocampal formation, Functional Laterality, Functional connectivity, 03 medical and health sciences, 0302 clinical medicine, Alzheimer Disease, Reference Values, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, medicine, Humans, Resting state, Prefrontal cortex, Anterior cingulate cortex, Default mode network, Aged, Functional MRI, 030304 developmental biology, 0303 health sciences, Resting state fMRI, Middle Aged, Alzheimer's disease, Magnetic Resonance Imaging, medicine.anatomical_structure, nervous system, Neurology, Posterior cingulate, Female, Psychology, Neuroscience, 030217 neurology & neurosurgery
Abstract: A selective distribution of Alzheimer's disease (AD) pathological lesions in specific cortical layers isolates the hippocampus from the rest of the brain. However, functional connectivity between the hippocampus and other brain regions remains unclear in AD. Here, we employ a resting state functional MRI (fMRI) to examine changes in hippocampal connectivity comparing 13 patients with mild AD versus 13 healthy age-matched controls. Hippocampal connectivity was investigated by examination of the correlation between low frequency fMRI signal fluctuations in the hippocampus and those in all other brain regions. We found that functional connectivity between the right hippocampus and a set of regions was disrupted in AD; these regions are: medial prefrontal cortex (MPFC), ventral anterior cingulate cortex (vACC), right inferotemporal cortex, right cuneus extending into precuneus, left cuneus, right superior and middle temporal gyrus and posterior cingulate cortex (PCC). We also found increased functional connectivity between the left hippocampus and the right lateral prefrontal cortex in AD. In addition, rightward asymmetry of hippocampal connectivity observed in elderly controls was diminished in AD patients. The disrupted hippocampal connectivity to the MPFC, vACC and PCC provides further support for decreased activity in "default mode network" previously shown in AD. The decreased connectivity between the hippocampus and the visual cortices might indicate reduced integrity of hippocampus-related cortical networks in AD. Moreover, these findings suggest that resting-state fMRI might be an appropriate approach for studying pathophysiological changes in early AD.
Published: 2006

21. Fingerprint registration by maximization of mutual information

Author: Tianzi Jiang, Jianwei Yang, Chaozhe Zhu, Lifeng Liu, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), National Laboratory of Pattern Recognition [Beijing] (NLPR), and Institute of Automation - Chinese Academy of Sciences
Subjects: Biometrics, Computer science, Image quality, Data_MISCELLANEOUS, Feature extraction, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, 0211 other engineering and technologies, Information Storage and Retrieval, Image registration, 02 engineering and technology, Sensitivity and Specificity, Pattern Recognition, Automated, Fingers, orientation field, Artificial Intelligence, registration, Fingerprint, Image Interpretation, Computer-Assisted, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, 0202 electrical engineering, electronic engineering, information engineering, Humans, Computer vision, Dermatoglyphics, Skin, 021101 geological & geomatics engineering, Minutiae, Likelihood Functions, business.industry, Orientation (computer vision), matching, Reproducibility of Results, mutual information (MI), Pattern recognition, fingerprints, Mutual information, minutia, Image Enhancement, Computer Graphics and Computer-Aided Design, Feature (computer vision), Subtraction Technique, 020201 artificial intelligence & image processing, Artificial intelligence, business, Algorithms, Software
Abstract: Fingerprint registration is a critical step in fingerprint matching. Although a variety of registration alignment algorithms have been proposed, accurate fingerprint registration remains an unresolved problem. We propose a new algorithm for fingerprint registration using orientation field. This algorithm finds the correct alignment by maximization of mutual information between features extracted from orientation fields of template and input fingerprint images. Orientation field, representing the flow of ridges, is a relatively stable global feature of fingerprint images. This method uses the statistics and distribution of global feature of fingerprint images so that it is robust to image quality and local changes in images. The primary characteristic of this method is that it uses this stable global feature to align fingerprints, and that its behavior may resemble the way humans compare fingerprints. Experimental results show that the occurrence of misalignment is dramatically reduced and that registration accuracy is greatly improved at the same time, leading to enhanced matching performance.
Published: 2006

22. Whole Earth telescope observations of the ZZ Ceti star HL Tau 76

Author: Waldemar Ogloza, P. Ibbetson, S. Zola, Matt A. Wood, M. S. O'Brien, Nicole M. Silvestri, R. E. Nather, Antonio Kanaan, E. W. Klumpe, Travis S. Metcalfe, S. Bernabei, G. Vauclair, Dong Xu, E. G. Meištas, Luciano Fraga, B. N. Ashoka, R. Kalytis, Ana Ulla, J. Krzesinski, N. Dolez, Michael D. Reed, Denis J. Sullivan, T. J. Ahrens, T. Sullivan, Rimvydas Janulis, Divas Sanwal, S. J. Kleinman, M. Chevreton, J. E. Solheim, Steven D. Kawaler, Pawel Moskalik, Roberto Silvotti, J. M. Gonzalez Perez, J. N. Fu, Xiao-Jun Jiang, Eran O. Ofek, Elia M. Leibowitz, D. Ališauskas, Anjum S. Mukadam, Gerald Handler, D. Kilkenny, Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Escola de Odontologia, UNIVALE, Unilever R&D, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Rotation period, 010308 nuclear & particles physics, stars: white dwarfs, Spectral density, Astronomy, White dwarf, Astronomy and Astrophysics, Astrophysics, stars: interiors, Star (graph theory), Rotation, 01 natural sciences, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Telescope, Space and Planetary Science, Duty cycle, law, 0103 physical sciences, stars: oscillations, Instability strip, 010303 astronomy & astrophysics, stars: individual: HL Tau 76
Abstract: International audience; This paper analyses the Whole Earth Telescope observations of HL Tau 76, the first discovered pulsating DA white dwarf. The star was observed during two Whole Earth Telescope campaigns. It was a second priority target during the XCOV13 campaign in 1996 and the first priority one during the XCOV18 campaign in 1999. The 1999 campaign reached 66.5% duty cycle. With a total duration of 18 days, the frequency resolution achieved is 0.68 ?Hz. With such a frequency resolution, we were able to find as many as 78 significant frequencies in the power spectrum, of which 34 are independent frequencies after removal of all linear combinations. In taking into account other frequencies present during the 1996 WET campaign and those present in earlier data, which do not show up in the 1999 data set, we find a total of 43 independent frequencies. This makes HL Tau 76 the richest ZZ Ceti star in terms of number of observed pulsation modes. We use those pulsation frequencies to determine as much as possible of the internal structure of HL Tau 76. The pulsations in HL Tau 76 cover a wide range of periods between 380 s and 1390 s. We propose an identification for 39 of those 43 frequencies in terms of ?=1 and ?=2 non-radial g-modes split by rotation. We derive an average rotation period of 2.2 days. The period distribution of HL Tau 76 is best reproduced if the star has a moderately "thick" hydrogen mass fraction log qH ? -7.0. The results presented in this paper constitute a starting point for a detailed comparison of the observed periods with the periods calculated for models as representative as possible of HL Tau 76.
Published: 2006

23. Non-Negative Spherical Deconvolution (NNSD) for Fiber Orientation Distribution Function Estimation

Author: Jian Cheng, Tianzi Jiang, Dinggang Shen, Rachid Deriche, Pew Thian Yap, Biomedical Research Imaging Center [North Carolina] (BRIC), University of North Carolina [Chapel Hill] (UNC), University of North Carolina System (UNC)-University of North Carolina System (UNC), Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), and Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Unit sphere, Mathematical analysis, Spherical harmonics, Probability density function, Geometry, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Distribution function, Distribution (mathematics), Cartesian tensor, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Deconvolution, Anisotropy, 030217 neurology & neurosurgery, Mathematics
Abstract: In diffusion Magnetic Resonance Imaging (dMRI), Spherical Deconvolution (SD) is a commonly used approach for estimating the fiber Orientation Distribution Function (fODF). As a Probability Density Function (PDF) that characterizes the distribution of fiber orientations, the fODF is expected to be non-negative and to integrate to unity on the continuous unit sphere ${\mathbb{S}}^{2}$. However, many existing approaches, despite using continuous representation such as Spherical Harmonics (SH), impose non-negativity only on discretized points of ${\mathbb{S}}^{2}$. Therefore, non-negativity is not guaranteed on the whole ${\mathbb{S}}^{2}$. Existing approaches are also known to exhibit false positive fODF peaks, especially in regions with low anisotropy, causing an over-estimation of the number of fascicles that traverse each voxel. This paper proposes a novel approach, called Non-Negative SD (NNSD), to overcome the above limitations. NNSD offers the following advantages. First, NNSD is the first SH based method that guarantees non-negativity of the fODF throughout the unit sphere. Second, unlike approaches such as Maximum Entropy SD (MESD), Cartesian Tensor Fiber Orientation Distribution (CT-FOD), and discrete representation based SD (DR-SD) techniques, the SH representation allows closed form of spherical integration, efficient computation in a low dimensional space resided by the SH coefficients, and accurate peak detection on the continuous domain defined by the unit sphere. Third, NNSD is significantly less susceptible to producing false positive peaks in regions with low anisotropy. Evaluations of NNSD in comparison with Constrained SD (CSD), MESD, and DR-SD (implemented using L1-regularized least-squares with non-negative constraint), indicate that NNSD yields improved performance for both synthetic and real data. The performance gain is especially prominent for high resolution ${(1.25\,\text{mm})}^{3}$ data.
Published: 2013

24. Targeted optical biopsies for surveillance endoscopies

Author: Selen Atasoy, Guang-Zhong Yang, Nassir Navab, Diana Mateus, Alexander Meining, Computer Aided Medical Procedures & Augmented Reality (CAMPAR), Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Technische Universität München [München] (TUM), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), and Mateus, Diana
Subjects: Diagnostic Imaging, Endoscope, Biopsy, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Tissue sample, 02 engineering and technology, [INFO] Computer Science [cs], 030218 nuclear medicine & medical imaging, 03 medical and health sciences, Esophagus, 0302 clinical medicine, Image Processing, Computer-Assisted, 0202 electrical engineering, electronic engineering, information engineering, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Cluster Analysis, Humans, Computer vision, [INFO]Computer Science [cs], Cluster analysis, Endoscopes, Confocal laser endomicroscopy, Microscopy, Confocal, medicine.diagnostic_test, business.industry, Stomach, Reproducibility of Results, Endoscopy, Optical Biopsy, 3. Good health, Surveillance endoscopy, [INFO.INFO-TI] Computer Science [cs]/Image Processing [eess.IV], [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], 020201 artificial intelligence & image processing, Artificial intelligence, business, Algorithms
Abstract: International audience; Recent introduction of probe-based confocal laser endomicroscopy (pCLE) allowed for the acquisition of in-vivo optical biopsies during the endoscopic examination without removing any tissue sample. The non-invasive nature of the optical biopsies makes the re-targeting of previous biopsy sites in surveillance examinations difficult due to the absence of scars or surface landmarks. In this work, we introduce a new method for recognition of optical biopsy scenes of the diagnosis endoscopy during serial surveillance examinations. To this end, together with our clinical partners, we propose a new workflow involving two-run surveillance endoscopies to reduce the ill-posedness of the task. In the first run, the endoscope is guided from the mouth to the z-line (junction from the oesophagus to the stomach). Our method relies on clustering the frames of the diagnosis and the first run surveillance (S1) endoscopy into several scenes and establishing cluster correspondences accross these videos. During the second run surveillance (S2), the scene recognition is performed in real-time and in-vivo based on the cluster correspondences. Detailed experimental results demonstrate the feasibility of the proposed approach with 89.75% recall and 80.91% precision on 3 patient datasets.
Published: 2012

25. Diffusion magnetic resonance imaging for Brainnetome: A critical review

Author: Nianming Zuo, Tianzi Jiang, Jian Cheng, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physiology, Review, Brain mapping, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Image Processing, Computer-Assisted, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, magnetic resonance imaging, Cognitive science, Modularity (networks), medicine.diagnostic_test, General Neuroscience, Brain, Magnetic resonance imaging, General Medicine, Human physiology, Diffusion mri, Diffusion Magnetic Resonance Imaging, Connectome, brain mapping, Nerve Net, Psychology, Neuroscience, 030217 neurology & neurosurgery, Diffusion MRI
Abstract: International audience; Increasing evidence shows that the human brain is a highly self-organized system that shows attributes of smallworldness, hierarchy and modularity. The “connectome” was conceived several years ago to identify the underpinning physical connectivities of brain networks. The need for an integration of multi-spatial and -temporal approaches is becoming apparent. Therefore, the “Brainnetome” (brain-net-ome) project was proposed. Diffusion magnetic resonance imaging (dMRI) is a non-invasive way to study the anatomy of brain networks. Here, we review the principles of dMRI, its methodologies, and some of its clinical applications for the Brainnetome. Future research in this field is discussed.
Published: 2012

26. Estimation and Processing of Ensemble Average Propagator and Its Features in Diffusion MRI

Author: Cheng, Jian, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis, Rachid Deriche and Tianzi Jiang(Rachid.Deriche@inria.fr and jiangtz@nlpr.ia.ac.cn), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), and Deriche, Rachid
Subjects: [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, Ensemble Average Propagator, Orientation Distribution Function, Riemannian Framework, 030218 nuclear medicine & medical imaging, Diffusion MRI, 03 medical and health sciences, 0302 clinical medicine, [INFO.INFO-TI] Computer Science [cs]/Image Processing [eess.IV], [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], HARDI, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, High Angular Resolution Diffusion Imaging, Square Root Parameterized Estimation, 030217 neurology & neurosurgery, Spherical Polar Fourier Imaging
Abstract: Diffusion MRI (dMRI) is the unique technique to infer the microstructure of the white matter in vivo and noninvasively, by modeling the diffusion of water molecules. Ensemble Average Propagator (EAP) and Orientation Distribution Function (ODF) are two important Probability Density Functions (PDFs) which reflect the water diffusion. Estimation and processing of EAP and ODF is the central problem in dMRI, and is also the first step for tractography. Diffusion Tensor Imaging (DTI) is the most widely used estimation method which assumes EAP as a Gaussian distribution parameterized by a tensor. Riemannian framework for tensors has been proposed successfully in tensor estimation and processing. However, since the Gaussian EAP assumption is oversimplified, DTI can not reflect complex microstructure like fiber crossing. High Angular Resolution Diffusion Imaging (HARDI) is a category of methods proposed to avoid the limitations of DTI. Most HARDI methods like Q-Ball Imaging (QBI) need some assumptions and only can handle the data from single shell (single $b$ value), which are called as single shell HARDI (sHARDI) methods. However, with the development of scanners and acquisition methods, multiple shell data becomes more and more practical and popular. This thesis focuses on the estimation and processing methods in multiple shell HARDI (mHARDI) which can handle the diffusion data from arbitrary sampling scheme. There are many original contributions in this thesis. -First, we develop the analytical Spherical Polar Fourier Imaging (SPFI), which represents the signal using SPF basis and obtains EAP and its various features including ODFs and some scalar indices like Generalized Fractional Anisotropy (GFA) from analytical linear transforms. In the implementation of SPFI, we present two ways for scale estimation and propose to consider the prior $E(0)=1$ in estimation process. -Second, a novel Analytical Fourier Transform in Spherical Coordinate (AFT-SC) framework is proposed to incorporate many sHARDI and mHARDI methods, explore their relation and devise new analytical EAP/ODF estimation methods. -Third, we present some important criteria to compare different HARDI methods and illustrate their advantages and limitations. -Fourth, we propose a novel diffeomorphism invariant Riemannian framework for ODF and EAP processing, which is a natural generalization of previous Riemannian framework for tensors, and can be used for general PDF computing by representing the square root of the PDF called wavefunction with orthonormal basis. In this Riemannian framework, the exponential map, logarithmic map and geodesic have closed forms, the weighted Riemannian mean and median uniquely exist and can be estimated from an efficient gradient descent. Log-Euclidean framework and Affine-Euclidean framework are developed for fast data processing. -Fifth, we theoretically and experimentally compare the Euclidean metric and Riemannian metric for tensors, ODFs and EAPs. -Finally, we propose the Geodesic Anisotropy (GA) to measure the anisotropy of EAPs, Square Root Parameterized Estimation (SRPE) for nonnegative definite ODF/EAP estimation, weighted Riemannian mean/median for ODF/EAP interpolation, smoothing, atlas estimation. The concept of \emph{reasonable mean value interpolation} is presented for interpolation of general PDF data., L'IRM de diffusion est a ce jour la seule technique a meme d'observer in vivo et de fac¸on non-invasive les structures fines de la mati'ere blanche, en modelisant la diffusion des molecules d'eau. Le propagateur moyen (EAP pour Ensemble average Propagator en anglais) et la fonction de distribution d'orientation (ODF pour Orientation Distribution Function en anglais) sont les deux fonctions de probabilites d'int'erˆet pour caracteriser la diffusion des molecules d'eau. Le probleme central en IRM de diffusion est la reconstruction et le traitement de ces fonctions (EAP et ODF); c'est aussi le point de depart pour la tractographie des fibres de la mati'ere blanche. Le formalisme du tenseur de diffusion (DTI pour Diffusion Tensor Imaging en anglais) est le modele le plus couramment utilise, et se base sur une hypothese de diffusion gaussienne. Il existe un cadre riemannien qui permet d'estimer et de traiter correctement les images de tenseur de diffusion. Cependant, l'hypothese d'une diffusion gaussienne est une simplification, qui ne permet pas de d'écrire les cas ou la structure microscopique sous-jacente est complexe, tels que les croisements de faisceaux de fibres. L'imagerie 'a haute resolution angulaire (HARDI pour High Angular Resolution Diffusion Imaging en anglais) est un ensemble de methodes qui permettent de contourner les limites du modele tensoriel. La plupart des m'ethodes HARDI 'a ce jour, telles que l'imagerie spherique de l'espace de Fourier (QBI pour Q-Ball Imaging en anglais) se basent sur des hypoth'eses reductrices, et prennent en compte des acquisitions qui ne se font que sur une seule sphere dans l'espace de Fourier (sHARDI pour single-shell HARDI en anglais), c'est-a-dire une seule valeur du coefficient de ponderation b. Cependant, avec le developpement des scanners IRM et des techniques d'acquisition, il devient plus facile d'acquerir des donn'ees sur plusieurs sph'eres concentriques. Cette th'ese porte sur les methodes d'estimation et de traitement de donnees sur plusieurs spheres (mHARDI pour multiple-shell HARDI en anglais), et de facon generale sur les methodes de reconstruction independantes du schema d'echantillonnage. Cette these presente plusieurs contributions originales. En premier lieu, nous developpons l'imagerie par transformee de Fourier en coordonnees spheriques (SPFI pour Spherical Polar Fourier Imaging en anglais), qui se base sur une representation du signal dans une base de fonctions a parties radiale et angulaire separables (SPF basis pour Spherical Polar Fourier en anglais). Nous obtenons, de fac¸on analytique et par transformations lineaires, l'EAP ainsi que ses caracteristiques importantes : l'ODF, et des indices scalaires tels que l'anisotropie fractionnelle generalisee (GFA pour Generalized Fractional Anisotropy en anglais). En ce qui concerne l'implementation de SPFI, nous presentons deux methodes pour determiner le facteur d'echelle, et nous prenons en compte le fait que E(0) = 1 dans l'estimation. En second lieu, nous presentons un nouveau cadre pour une transformee de Fourier analytique en coordonnees spheriques (AFT-SC pour Analytical Fourier Transform in Spherical Coordinate en anglais), ce qui permet de considerer aussi bien les methodes mHARDI que sHARDI, d'explorer les relations entre ces methodes, et de developper de nouvelles techniques d'estimation de l'EAP et de l'ODF. Nous presentons en troisieme lieu d'importants crit'eres de comparaison des differentes methodes HARDI, ce qui permet de mettre en lumiere leurs avantages et leurs limites. Dans une quatrieme partie, nous proposons un nouveau cadre riemannien invariant par diffeomorphisme pour le traitement de l'EAP et de l'ODF. Ce cadre est une generalisation de la m'ethode riemannienne precedemment appliquee au tenseur de diffusion. Il peut etre utilise pour l'estimation d'une fonction de probabilite representee par sa racine carree, appelee fonction d'onde, dans une base de fonctions orthonormale. Dans ce cadre riemannien, les applications exponentielle et logarithmique, ainsi que les geodesiques ont une forme analytique. La moyenne riemannienne ponderee ainsi que la mediane existent et sont uniques, et peuvent etre calculees de facon efficace par descente de gradient. Nous developpons egalement un cadre log-euclidien et un cadre affine-euclidien pour un traitement rapide des donnees. En cinquieme partie, nous comparons, theoriquement et sur un plan exp'erimental, les metriques euclidiennes et riemanniennes pour les tenseurs, l'ODF et l'EAP. Finalement, nous proposons l'anisotropie geodesique (GA pour Geodesic Anisotropy en anglais) pour mesurer l'anisotropie de l'EAP; une parametrisation par la racine carrée (SRPE pour Square-Root Parameterized Estimation en anglais) pour l'estimation d'un EAP et d'une ODF positifs; la mediane et la moyenne riemanniennes ponderees pour l'interpolation, le lissage et la construction d'atlas bas'es sur l'ODF et de l'EAP. Nous introduisons la notion de valeur moyenne raisonnable pour l'interpolation de fonction de probabilites en general.
Published: 2012
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27. Optimal Design of Multiple Q-shells experiments for Diffusion MRI

Author: Emmanuel Caruyer, Jian Cheng, Christophe Lenglet, Guillermo Sapiro, Tianzi Jiang, Rachid Deriche, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Center for Magnetic Resonance Research [Minneapolis] (CMRR), University of Minnesota Medical School, University of Minnesota System-University of Minnesota System, Department of Electrical and Computer Engineering [Minneapolis] (ECE), University of Minnesota [Twin Cities] (UMN), This work was partly supported by the Computational Diffusion MRI INRIA Associate Team Program, NIH grants P41 RR008079 and P30 NS057091. C.L. and G.S. were partly supported by the NIH Human Connectome Project 1U54MH091657-01 and grant R01 EB008432. C.L. was partly supported by the University of Minnesota Institute for Translational Neuroscience. G.S. received additional support from ONR, NGA, NSF, DARPA, NSSEFF, and ARO., and University of Minnesota [Twin Cities]
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: diffusion mri; experimental design; sampling scheme; diffusion propagator; optimal samplingdiffusion mri; experimental design; sampling scheme; diffusion propagator; optimal sampling; International audience; Recent advances in diffusion MRI make use of the diffusion signal sampled on the whole Q-space, rather than on a single sphere. While much effort has been done to design uniform sampling schemes for single shell experiment, it is yet not clear how to build a strategy to sample the diffusion signal in the whole Fourier domain. In this article, we propose a method to generate acquisition schemes for multiple Q-shells experiment in diffusion MRI. The acquisition protocols we design are incremental, which means they remain approximately optimal when truncated before the acquisition is complete. Our method is fast, incremental, and we can generate diffusion gradients schemes for any number of acquisitions, any number of shells, and any number of points per shell. The samples arranged on different shells do not share the same directions. The method is tested for Spherical Polar Fourier reconstruction of the diffusion signal, and based on Monte-Carlo simulations, several preferred acquisition parameters are identified.
Published: 2011

28. Compressive Sensing Ensemble Average Propagator Estimation via L1 Spherical Polar Fourier Imaging

Author: Jian Cheng, Sylvain Merlet, Aurobrata Ghosh, Emmanuel Caruyer, Tianzi Jiang, Rachid Deriche, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), and Cheng, Jian
Subjects: [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: International audience; In diffusion MRI (dMRI) domain, many High Angular Resolution Diffusion Imaging (HARDI) methods were proposed to estimate Ensemble Average Propagator (EAP) and Orientation Distribution Function (ODF). They normally need many samples, which limits their applications. Some Compressive Sensing (CS) based methods were proposed to estimate ODF in Q-Ball Imaging (QBI) from limited samples. However EAP estimation is much more difficult than ODF in QBI. Recently Spherical Polar Fourier Imaging (SPFI) was proposed to represent diffusion signal using Spherical Polar Fourier (SPF) basis without specific assumption on diffusion signals and analytically obtain EAP and ODF via the Fourier dual SPF (dSPF) basis from arbitrarily sampled signal. Normally the coefficients of SPF basis are estimated via Least Square with weighted L2 norm regularization (L2-SPFI). However, L2-SPFI needs a truncated basis to avoid overfitting, which brings some estimation errors. By considering the Fourier relationship between EAP and signal and the Fourier basis pair provided in SPFI, we propose a novel EAP estimation method, named L1-SPFI, to estimate EAP from limited samples using CS technique, and favorably compare it to the classical L2-SPFI method. L1-SPFI estimates the coefficients in SPFI using least square with weighted L1 norm regularization. The weights are designed to enhance the sparsity. L1-SPFI significantly accelerates the ordinary CS based Fourier reconstruction method. This is performed by using SPF basis pair in CS estimation process which avoids the numerical Fourier transform in each iteration step. By considering high order basis in L1 optimization, L1-SPFI improves EAP reconstruction especially for the angular resolution. The proposed L1-SPFI was validated by synthetic, phantom and real data. The CS EAP and ODF estimations are discussed in detail and we show that recovering the angular information from CS EAP requires much less samples than exact CS EAP reconstruction. Various experiments on synthetic, phantom and real data validate the fact that SPF basis can sparsely represent DW-MRI signals and L1-SPFI largely improves the CS EAP reconstruction especially the angular resolution.
Published: 2011

29. Diffeomorphism Invariant Riemannian Framework for Ensemble Average Propagator Computing

Author: Jian Cheng, Tianzi Jiang, Rachid Deriche, Aurobrata Ghosh, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: Geodesic, Topology, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, Fourier transform, symbols, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Applied mathematics, Orthonormal basis, Diffeomorphism, Information geometry, Invariant (mathematics), Principal geodesic analysis, 030217 neurology & neurosurgery, Smoothing, Mathematics
Abstract: International audience; Background: In Diffusion Tensor Imaging (DTI), Riemannian framework based on Information Geometry theory has been proposed for processing tensors on estimation, interpolation, smoothing, regularization, segmentation, statistical test and so on. Recently Riemannian framework has been generalized to Orientation Distribution Function (ODF) and it is applicable to any Probability Density Function (PDF) under orthonormal basis representation. Spherical Polar Fourier Imaging (SPFI) was proposed for ODF and Ensemble Average Propagator (EAP) estimation from arbitrary sampled signals without any assumption. Purpose: Tensors only can represent Gaussian EAP and ODF is the radial integration of EAP, while EAP has full information for diffusion process. To our knowledge, so far there is no work on how to process EAP data. In this paper, we present a Riemannian framework as a mathematical tool for such task. Method: We propose a state-of-the-art Riemannian framework for EAPs by representing the square root of EAP, called wavefunction based on quantum mechanics, with the Fourier dual Spherical Polar Fourier (dSPF) basis. In this framework, the exponential map, logarithmic map and geodesic have closed forms, and weighted Riemannian mean and median uniquely exist. We analyze theoretically the similarities and differences between Riemannian frameworks for EAPs and for ODFs and tensors. The Riemannian metric for EAPs is diffeomorphism invariant, which is the natural extension of the affine-invariant metric for tensors. We propose Log-Euclidean framework to fast process EAPs, and Geodesic Anisotropy (GA) to measure the anisotropy of EAPs. With this framework, many important data processing operations, such as interpolation, smoothing, atlas estimation, Principal Geodesic Analysis (PGA), can be performed on EAP data. Results and Conclusions: The proposed Riemannian framework was validated in synthetic data for interpolation, smoothing, PGA and in real data for GA and atlas estimation. Riemannian median is much robust for atlas estimation.
Published: 2011

30. A Riemannian Framework for Ensemble Average Propagator Computing

Author: Cheng, Jian, Ghosh, Aurobrata, Jiang, Tianzi, Deriche, Rachid, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: International audience; In Diffusion Tensor Imaging (DTI), Riemannian framework (RF) [1] has been proposed for processing tensors, which is based on Information Geometry theory. Many papers have shown that RF is useful in tensor estimation, interpolation, smoothing, regularization, segmentation and so on. Recently RF also has been proposed for Orientation Distribution Function (ODF) computing [2,3] and it is applicable to any Probability Density Function (PDF) based on any orthonormal basis representation. Spherical Polar Fourier Imaging (SPFI) [4,5] was proposed recently to fast and robustly estimate the ODF and Ensemble Average Propagator (EAP) from arbitrary sampled DWI signals. In this paper, we propose the RF for EAPs and implement it via SPFI. We proved that the RF for EAPs is diffeomorphism invariant, which is the natural extension of affine invariant RF for tensors. It could avoid the so-called swelling effect for interpolating EAPs, just like the RF for tensors. We also propose the Log-Euclidean framework (LEF), Affine-Euclidean framework (AEF), for fast processing EAPs, and Geometric Anisotropy (GA) for measuring the anisotropy of EAPs, which are all the extensions of previous concepts in RM for tensors respectively.
Published: 2011

31. Spherical Polar Fourier EAP and ODF Reconstruction via Compressed Sensing in Diffusion MRI

Author: Rachid Deriche, Aurobrata Ghosh, Jian Cheng, Sylvain Merlet, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: Iterative reconstruction, Imaging phantom, 030218 nuclear medicine & medical imaging, Diffusion MRI, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, Optics, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Diffusion (business), Spherical Polar Fourier, Physics, business.industry, Mathematical analysis, Ensemble Average, Orientation Distribution Function, Propagator, Compressed sensing, Fourier transform, Fourier analysis, Propagator recovery, symbols, business, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, 030217 neurology & neurosurgery
Abstract: International audience; In diffusion magnetic resonance imaging (dMRI), the Ensemble Average Propagator (EAP), also known as the propagator, describes completely the water molecule diffusion in the brain white matter without any prior knowledge about the tissue shape. In this paper, we describe a new and efficient method to accurately reconstruct the EAP in terms of the Spherical Polar Fourier (SPF) basis from very few diffusion weighted magnetic resonance images (DW-MRI). This approach nicely exploits the duality between SPF and a closely related basis in which one can respectively represent the EAP and the diffusion signal using the same coefficients, and efficiently combines it to the recent acquisition and reconstruction technique called Compressed Sensing (CS). Our work provides an efficient analytical solution to estimate, from few measurements, the diffusion propagator at any radius. We also provide a new analytical solution to extract an important feature characterising the tissue microstructure: the Orientation Distribution Function (ODF). We illustrate and prove the effectiveness of our method in reconstructing the propagator and the ODF on both noisy multiple q-shell synthetic and phantom data.
Published: 2011

32. Interactive Blood-Coil Simulation in Real-time during Aneurysm Embolization

Author: Stéphane Cotin, Chunhong Pan, Yiyi Wei, Songde Ma, Jérémie Allard, Le Fang, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Simulation in Healthcare using Computer Research Advances (SHACRA), Laboratoire d'Informatique Fondamentale de Lille (LIFL), Université de Lille, Sciences et Technologies-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lille, Sciences Humaines et Sociales-Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lille, Sciences Humaines et Sociales-Centre National de la Recherche Scientifique (CNRS)-Inria Lille - Nord Europe, Institut National de Recherche en Informatique et en Automatique (Inria)-Inria Nancy - Grand Est, Institut National de Recherche en Informatique et en Automatique (Inria), Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: fluid-solid interaction, Medical procedure, 02 engineering and technology, Aneurysm embolization, drag force, 030218 nuclear medicine & medical imaging, discrete exterior calculus, 03 medical and health sciences, 0302 clinical medicine, Aneurysm, porous media, 0202 electrical engineering, electronic engineering, information engineering, medicine, Simulation, General Engineering, Process (computing), 020207 software engineering, Blood flow, medicine.disease, Computer Graphics and Computer-Aided Design, [INFO.INFO-GR]Computer Science [cs]/Graphics [cs.GR], 3. Good health, Visual computing, Human-Computer Interaction, Mesh generation, Electromagnetic coil
Abstract: International audience; Over the last decade, remarkable progress has been made in the field of endovascular treatment of aneurysms. Technological advances continue to make it possible for a growing number of patients with cerebral aneurysms to be treated with a variety of endovascular strategies, essentially using detachable platinum coils. Yet, coil embolization remains a very complex medical procedure for which careful planning must be combined with advanced technical skills in order to be successful. In this paper, we describe a complete process for patient-specific simulations of coil embolization, from mesh generation with medical datasets to computation of coil-flow bilateral influence. We propose a new method for simulating the complex blood flow patterns that take place within the aneurysm, and for simulating the interaction of coils with this flow. This interaction is twofold, first involving the impact of the flow on the coil during the initial stages of its deployment, and second concerning the decrease of blood velocity within the aneurysm, as a consequence of coil packing. We also propose an approach to achieve real-time computation of coil-flow bilateral influence, necessary for interactive simulation. This in turns allows to dynamically plan coil embolization for two key steps of the procedure: choice and placement of the first coils, and assessment of the number of coils necessary to reduce aneurysmal blood velocity and wall pressure. Finally, we provide the blood flow simulation results on several aneurysms with interesting clinical characteristics both in 2D and 3D, as well as comparisons with a commercial package for validation. The coil embolization procesure is simulated within an aneurysm, and pre- and post-operative status is reported.
Published: 2011

33. Model-free and Analytical EAP Reconstruction via Spherical Polar Fourier Diffusion MRI

Author: Aurobrata Ghosh, Rachid Deriche, Tianzi Jiang, Jian Cheng, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), and Tianzi Jiang and Nassir Navab and Josien P. W. Pluim and Max A. Viergever
Subjects: Computer science, Orientation (computer vision), Speech recognition, Spherical harmonics, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, Fourier transform, Diffusion process, Fourier analysis, symbols, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Diffusion (business), Anisotropy, Algorithm, 030217 neurology & neurosurgery, Diffusion MRI
Abstract: International audience; How to estimate the diffusion Ensemble Average Propagator (EAP) from the DWI signals in q-space is an open problem in diffusion MRI field. Many methods were proposed to estimate the Orientation Distribution Function (ODF) that is used to describe the fiber direction. However, ODF is just one of the features of the EAP. Compared with ODF, EAP has the full information about the diffusion process which reflects the complex tissue micro-structure. Diffusion Orientation Transform (DOT) and Diffusion Spectrum Imaging (DSI) are two important methods to estimate the EAP from the signal. However, DOT is based on mono-exponential assumption and DSI needs a lot of samplings and very large b values. In this paper, we propose Spherical Polar Fourier Imaging (SPFI), a novel model-free fast robust analytical EAP reconstruction method, which almost does not need any assumption of data and does not need too many samplings. SPFI naturally combines the DWI signals with dierent b-values. It is an analytical linear transformation from the q-space signal to the EAP profile represented by Spherical Harmonics (SH).We validated the proposed methods in synthetic data, phantom data and real data. It works well in all experiments, especially for the data with low SNR, low anisotropy, and non-exponential decay.
Published: 2010

34. Model-Free, Regularized, Fast, and Robust Analytical Orientation Distribution Function Estimation

Author: Tianzi Jiang, Aurobrata Ghosh, Rachid Deriche, Jian Cheng, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: Orientation (computer vision), Computer science, Spherical harmonics, Mixture model, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, Fourier transform, Statistics, symbols, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Angular resolution, Tensor, Anisotropy, Algorithm, 030217 neurology & neurosurgery, Diffusion MRI
Abstract: International audience; High Angular Resolution Imaging (HARDI) can better explore the complex micro-structure of white matter compared to Diffusion Tensor Imaging (DTI). Orientation Distribution Function (ODF) in HARDI is used to describe the probability of the fiber direction. There are two type definitions of the ODF, which were respectively proposed in Q-Ball Imaging (QBI) and Diffusion Spectrum Imaging (DSI). Some analytical reconstructions methods have been proposed to estimate these two type of ODFs from single shell HARDI data. However they all have some assumptions and intrinsic modeling errors. In this article, we propose, almost without any assumption, a uniform analytical method to estimate these two ODFs from DWI signals in q space, which is based on Spherical Polar Fourier Expression (SPFE) of signals. The solution is analytical and is a linear transformation from the q-space signal to the ODF represented by Spherical Harmonics (SH). It can naturally combines the DWI signals in dierent Q-shells. Moreover It can avoid the intrinsic Funk-Radon Transform (FRT) blurring error in QBI and it does not need any assumption of the signals, such as the multiple tensor model and mono/multi-exponential decay. We validate our method using synthetic data, phantom data and real data. Our method works well in all experiments, especially for the data with low SNR, low anisotropy and non-exponential decay.
Published: 2010

35. Fast, Model-Free , Analytical ODF Reconstruction from the Q-Space Signal

Author: Cheng, Jian, Ghosh, Aurobrata, Jiang, Tianzi, Deriche, Rachid, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: International audience; The orientation distribution function (ODF) is very important in diffusion MRI. There are two types of ODFs. One is proposed using radial projection in Q-ball imaging [7]. Another one is the marginal pdf proposed in diffusion spectrum imaging (DSI) [8]. Since the marginal pdf is much sharper and mathematically correct, it could be more useful. Recently some reconstruction methods were proposed for this kind of ODF [1, 6]. They are both based on mono-exponential model, globally or locally, which has some intrinsic modeling error [4]. Although the authors in [1] extended the mono-exponential model to multi-exponential model, this multi-exponential model needs to be estimated non-linearly for every voxel and only in some special sampling scheme it has a analytical solution. Here we give a model-free analytical reconstruction method based on the Spherical Polar Fourier expression of the signal. It can estimate the ODF fast and analytically from the signal.
Published: 2010

36. Riemannian Median and Its Applications for Orientation Distribution Function Computing

Author: Cheng, Jian, Ghosh, Aurobrata, Jiang, Tianzi, Deriche, Rachid, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: International audience; The geometric median is a classic robust estimator of centrality for data in Euclidean spaces, and it has been generalized in analytical manifold in [1]. Recently, an intrinsic Riemannian framework for Orientation Distribution Function (ODF) was proposed for the calculation in ODF field [2]. In this work, we prove the unique existence of the Riemannian median in ODF space. Then we explore its two potential applications, median filtering and atlas estimation.
Published: 2010

37. Dopamine transporter binding is unaffected by L-DOPA administration in normal and MPTP-treated monkeys

Author: Piu Chan, Sandra Dovero, Tao Wu, Michael D. Hill, Pierre-Olivier Fernagut, Paula Ravenscroft, Zhenwen Chen, Erwan Bezard, Qin Li, Physiologie et physiopathologie de la signalisation cellulaire (PPSC), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-CHU Bordeaux [Bordeaux]-Centre National de la Recherche Scientifique (CNRS), Institut des Maladies Neurodégénératives [Bordeaux] (IMN), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Institute of Lab Animal Sciences, China Academy of Medical Sciences, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Department of Neurology, Xuanwu Hospital of Capital-University of Medical Sciences / Beijing, Motac Neuroscience, Department of Laboratory Animal Sciences, Capital Medical University, Beijing, Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), and Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-CHU Bordeaux [Bordeaux]-Centre National de la Recherche Scientifique (CNRS)
Subjects: Levodopa, Science, Dopamine Plasma Membrane Transport Proteins, Pharmacology, Neuroprotection, Antiparkinson Agents, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Neuroscience/Motor Systems, Dopamine, Animals, Medicine, Parkinson Disease, Secondary, Neurological Disorders/Movement Disorders, 030304 developmental biology, Dopamine transporter, Tomography, Emission-Computed, Single-Photon, 0303 health sciences, Multidisciplinary, biology, business.industry, MPTP, [SCCO.NEUR]Cognitive science/Neuroscience, Dopaminergic, Macaca mulatta, Corpus Striatum, 3. Good health, nervous system diseases, chemistry, nervous system, 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine, biology.protein, Autoradiography, Female, Neuroscience/Neurobiology of Disease and Regeneration, business, 030217 neurology & neurosurgery, Research Article, Protein Binding, medicine.drug
Abstract: International audience; BACKGROUND: Radiotracer imaging of the presynaptic nigrostriatal dopaminergic system is used to assess disease progression in Parkinson's disease (PD) and may provide a useful adjunct to clinical assessment during therapeutic trials of potential neuroprotective agents. Several clinical trials comparing dopamine agonists to L-DOPA or early vs. late L-DOPA have revealed differences between clinical assessment and imaging of the presynaptic dopaminergic system, hence questioning the comparability of these measures as neuroprotection outcome variables. Thus, results of these studies may have been affected by factors other than the primary biological process investigated. METHODOLOGY/PRINCIPAL FINDINGS: We tested the possibility that L-DOPA might interfere with DAT binding. Post-mortem DAT binding was conducted in normal and MPTP-treated macaque monkeys that were administered L-DOPA, acutely or chronically. In parallel, DAT SPECT was conducted in MPTP-treated animals that were administered chronic L-DOPA. [99mTc]TRODAT-1 SPECT binding was similarly reduced in all MPTP monkeys regardless of L-DOPA treatment. L-DOPA had no significant effect on post-mortem DAT binding either in saline or in MPTP-lesioned animals. CONCLUSIONS/SIGNIFICANCE: These data indicate that L-DOPA does not induce modifications of DAT expression detectable by SPECT of by DAT binding autoradiography, suggesting that differences between clinical assessment and radiotracer imaging in clinical trials may not be specifically related to L-DOPA treatment.
Published: 2010

38. Fast, model-free, analytical diffusion PDF profile estimation from the DWI signals

Author: Cheng, Jian, Ghosh, Aurobrata, Jiang, Tianzi, Deriche, Rachid, Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: International audience; How to estimate the diffusion Probability Density Function (PDF) from the q-space DWI signals is an open problem in diffusion MRI field. The diffusion PDF and the diffusion attenuation of dMRI signal is related by 3 dimensional Fourier transform. Diffusion Orientation Transform (DOT) [2] was proposed based on the assumption of the mono-exponential decay. Thanks to this assumption, PDF profile at a given radius R0 could be calculated analytically. However the estimated PDF is a low-pass filtered PDF. And this kind of low-pass filtering comes from the intrinsic modeling error [2], which is not a well defined filtering. Although DOT has been extended to multi-exponential model [2] and can reduce the modeling error dramatically, a nonlinear fitting needs to be performed for every voxel, which will limit its usefulness. Here we propose a model-free, linear, robust, analytical PDF profile reconstruction method which avoids the exponential or multi-exponential assumption.
Published: 2010

39. Nonparametric Mean Shift Functional Detection in the Functional Space for Task and Resting-state fMRI

Author: Cheng, Jian, Shi, Feng, Wang, Kun, Song, Ming, Jiang, Jiefeng, Xu, Lijuan, Jiang, Tianzi, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), Computer and biological vision (ODYSSEE), Département d'informatique de l'École normale supérieure (DI-ENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-École des Ponts ParisTech (ENPC), Department of Radiology [North Carolina], University of North Carolina [Chapel Hill] (UNC), University of North Carolina System (UNC)-University of North Carolina System (UNC), Biomedical Research Imaging Center [North Carolina] (BRIC), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Département d'informatique - ENS Paris (DI-ENS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Inria Sophia Antipolis - Méditerranée (CRISAM), École normale supérieure - Paris (ENS Paris)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Sophia Antipolis - Méditerranée (CRISAM), École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL)
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: International audience; In functional Magnetic Resonance Imaging (fMRI) data analysis, normalization of time series is an important and sometimes necessary preprocessing step in many widely used methods. The space of normalized time series with n time points is the unit sphere S^{n-2}, named the functional space. Riemannian framework on the sphere, including the geodesic, the exponential map, and the logarithmic map, has been well studied in Riemannian geometry. In this paper, by introducing the Riemannian framework in the functional space, we propose a novel nonparametric robust method, namely Mean Shift Functional Detection (MSFD), to explore the functional space. The first merit of the MSFD is that it does not need many assumptions on data which are assumed in many existing method, e.g. linear addition (GLM, PCA, ICA), uncorrelation (PCA), independence (ICA), the number and the shape of clusters (FCM). Second, MSFD takes into account the spatial information and can be seen as a multivariate extension of the functional connectivity analysis method. It is robust and works well for activation detection in task study even with a biased activation reference. It is also able to find the functional networks in resting-state study without a user-selected "seed" region. Third, it can enhance the boundary between different functional networks. Experiments were conducted on synthetic and real data to compare the performance of the proposed method with GLM and ICA. The experimental results validated the accuracy and robustness of MSFD, not only for activation detection in task study but also for functional network exploration in resting-state study.
Published: 2009

40. Toward Real-time Simulation of Blood-Coil Interaction during Aneurysm Embolization

Author: Yiyi Wei, Le Fang, Songde Ma, Stéphane Cotin, Chunhong Pan, Jérémie Allard, Simulation in Healthcare using Computer Research Advances (SHACRA), Laboratoire d'Informatique Fondamentale de Lille (LIFL), Université de Lille, Sciences et Technologies-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lille, Sciences Humaines et Sociales-Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lille, Sciences Humaines et Sociales-Centre National de la Recherche Scientifique (CNRS)-Inria Lille - Nord Europe, Institut National de Recherche en Informatique et en Automatique (Inria)-Inria Nancy - Grand Est, Institut National de Recherche en Informatique et en Automatique (Inria), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Guang-Zhong Yang and David Hawkes and Daniel Rueckert and Alison Noble and Chris Taylor, and Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Computer science, medicine.medical_treatment, 020207 software engineering, 02 engineering and technology, Blood flow, medicine.disease, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, [INFO.INFO-GR]Computer Science [cs]/Graphics [cs.GR], Aneurysm embolization, 03 medical and health sciences, 0302 clinical medicine, Aneurysm, Electromagnetic coil, Real-time simulation, 0202 electrical engineering, electronic engineering, information engineering, medicine, Aneurysm surgery, cardiovascular diseases, Embolization, Endovascular treatment, 030217 neurology & neurosurgery, Simulation, Coil embolization
Abstract: International audience; Over the last decade, remarkable progress has been made in the field of endovascular treatment of aneurysms. Technological advances continue to enable a growing number of patients with cerebral aneurysms to be treated with a variety of endovascular strategies, essentially using detachable platinum coils. Yet, coil embolization remains a very complex medical procedure for which careful planning must be combined with advanced technical skills in order to be successful. In this paper we propose a method for computing the complex blood flow patterns that take place within the aneurysm, and for simulating the interaction of coils with this flow. This interaction is twofold, first involving the impact of the flow on the coil during the initial stages of its deployment, and second concerning the decrease of blood velocity within the aneurysm, as a consequence of coil packing. We also propose an ap- proach to achieve real-time computation of coil-flow bilateral influence, necessary for interactive simulation. This in turns allows to dynamically plan coil embolization for two key steps of the procedure: choice and placement of the first coils, and assessment of the number of coils neces- sary to reduce aneurysmal blood velocity and wall pressure.
Published: 2009

41. A Riemannian Framework for Orientation Distribution Function Computing

Author: Rachid Deriche, Jian Cheng, Tianzi Jiang, Aurobrata Ghosh, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Computer and biological vision (ODYSSEE), Département d'informatique de l'École normale supérieure (DI-ENS), École normale supérieure - Paris (ENS Paris)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-École des Ponts ParisTech (ENPC), Département d'informatique - ENS Paris (DI-ENS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Inria Sophia Antipolis - Méditerranée (CRISAM), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Sophia Antipolis - Méditerranée (CRISAM), Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institute of Automation - Chinese Academy of Sciences-Institut National de Recherche en Informatique et en Automatique (Inria)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)
Subjects: Geodesic, Euclidean space, Mathematical analysis, Lagrange polynomial, 02 engineering and technology, Fundamental theorem of Riemannian geometry, 030218 nuclear medicine & medical imaging, Combinatorics, Fréchet mean, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, 0202 electrical engineering, electronic engineering, information engineering, symbols, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, 020201 artificial intelligence & image processing, Orthonormal basis, Information geometry, Fisher information metric, Mathematics
Abstract: International audience; Compared with Diffusion Tensor Imaging (DTI), High Angular Resolution Imaging (HARDI) can better explore the complex microstructure of white matter. Orientation Distribution Function (ODF) is used to describe the probability of the fiber direction. Fisher information metric has been constructed for probability density family in Information Geometry theory and it has been successfully applied for tensor computing in DTI. In this paper, we present a state of the art Riemannian framework for ODF computing based on Information Geometry and sparse representation of orthonormal bases. In this Riemannian framework, the exponential map, logarithmic map and geodesic have closed forms. And the weighted Frechet mean exists uniquely on this manifold. We also propose a novel scalar measurement, named Geometric Anisotropy (GA), which is the Riemannian geodesic distance between the ODF and the isotropic ODF. The Renyi entropy H_{1/2} of the ODF can be computed from the GA. Moreover, we present an Affine-Euclidean framework and a Log-Euclidean framework so that we can work in an Euclidean space. As an application, Lagrange interpolation on ODF field is proposed based on weighted Frechet mean. We validate our methods on synthetic and real data experiments. Compared with existing Riemannian frameworks on ODF, our framework is model-free. The estimation of the parameters, i.e. Riemannian coordinates, is robust and linear. Moreover it should be noted that our theoretical results can be used for any probability density function (PDF) under an orthonormal basis representation.
Published: 2009

42. Le coton, vecteur de développement des exploitations agricoles en zone soudanienne du Tchad ?

Author: Hauswirth, Damien, Reoungal, Djinodji, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Institut tchadien de recherche agronomique pour le développement (ITRAD), Institut tchadien de recherche agronomique pour le développement, and L. SEINY-BOUKAR, P. BOUMARD
Subjects: E20 - Organisation, administration et gestion des entreprises ou exploitations agricoles, Gossypium, E16 - Économie de la production, [SDV.SA.AEP]Life Sciences [q-bio]/Agricultural sciences/Agriculture, economy and politics, Coton
Abstract: International audience; Les résultats présentés sont extraits de deux études conduites en zone soudanienne du Tchad en 2006 et 2007. La première d'entre elles visait l'analyse des dynamiques des systèmes de production cotonniers et le diagnostic de l'organisation des producteurs de coton. La seconde a permis l'analyse des performances technico-économiques des exploitations agricoles et de différentes soles culturales. Ces deux études confirment la validité persistante d'une différenciation structurelle des exploitations reposant sur le genre du chef d'exploitation et son niveau d'équipement. Quel que soit le type de producteur considéré, la faiblesse des rendements obtenus et l'alea de production génèrent un risque économique accru par la volatilité intra-annuelle des cours des principaux produits agricoles. Cela se traduit aussi par une forte vulnérabilité alimentaire : une proportion significative de producteurs ne parvient pas à couvrir les besoins céréaliers familiaux. Bien que le coton constitue toujours un moyen quasi-exclusif d'accès aux intrants minéraux assorti d'un débouché commercial garanti sans volatilité intra-annuelle de cours, l'orientation cotonnière des producteurs ne garantit pas de meilleures performances dans le contexte d'une filière dysfonctionnelle. Au contraire, les résultats obtenus suggèrent que l'orientation cotonnière génèret un ensemble de risques techniques et économiques accroissant la vulnérabilité des producteurs. D'autres spéculations végétales offrent des performances économiques équivalentes. Le potentiel de ces productions à constituer des alternatives crédibles au coton ainsi que la capacité des acteurs à construire un environnement socio-économique propice demeurent deux questions clés pour le développement agricole de cet espace.
Published: 2009

43. Whole Earth Telescope observations of the hot helium atmosphere pulsating white dwarf EC20058-5234

Author: WET Collaboration, Sullivan, D. J., Metcalfe, T. S., O'Donoghue, D., Winget, D. E., Kilkenny, D., van Wyk, F., Kanaan, A., Kepler, S. O., Nitta, A., Kawaler, S. D., Montgomery, M. H., Nather, R. E., O'Brien, M. S., Bischoff-Kim, A., Wood, M., Jiang, X. J., Leibowitz, E. M., Ibbetson, P., Zola, S., Krzesinski, J., Pajdosz, G., Vauclair, G., Dolez, N., Chevreton, M., Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: oscillations [stars], Stellar mass, FOS: Physical sciences, Astrophysics, Compact star, stars: interiors, 01 natural sciences, law.invention, Photometry (optics), Telescope, photometric [techniques], [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Análise asterosismológica, techniques: photometric, Observatory, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, white dwarfs, Physics, interiors [stars], 010308 nuclear & particles physics, Estrelas ZZ Ceti, Astrophysics (astro-ph), White dwarf, Astronomy and Astrophysics, Effective temperature, stars: individual: EC 20058-5234, individual: EC 20058-5234 [stars], Fotometria astronômica, Anãs brancas, Pulsacoes estelares, 13. Climate action, Space and Planetary Science, stars: oscillations, Instability strip
Abstract: We present the analysis of a total of 177h of high-quality optical time-series photometry of the helium atmosphere pulsating white dwarf (DBV) EC 20058-5234. The bulk of the observations (135h) were obtained during a WET campaign (XCOV15) in July 1997 that featured coordinated observing from 4 southern observatory sites over an 8-day period. The remaining data (42h) were obtained in June 2004 at Mt John Observatory in NZ over a one-week observing period. This work significantly extends the discovery observations of this low-amplitude (few percent) pulsator by increasing the number of detected frequencies from 8 to 18, and employs a simulation procedure to confirm the reality of these frequencies to a high level of significance (1 in 1000). The nature of the observed pulsation spectrum precludes identification of unique pulsation mode properties using any clearly discernable trends. However, we have used a global modelling procedure employing genetic algorithm techniques to identify the n, l values of 8 pulsation modes, and thereby obtain asteroseismic measurements of several model parameters, including the stellar mass (0.55 M_sun) and T_eff (~28200 K). These values are consistent with those derived from published spectral fitting: T_eff ~ 28400 K and log g ~ 7.86. We also present persuasive evidence from apparent rotational mode splitting for two of the modes that indicates this compact object is a relatively rapid rotator with a period of 2h. In direct analogy with the corresponding properties of the hydrogen (DAV) atmosphere pulsators, the stable low-amplitude pulsation behaviour of EC 20058 is entirely consistent with its inferred effective temperature, which indicates it is close to the blue edge of the DBV instability strip. (abridged), 19 pages, 8 figures, 5 tables, MNRAS accepted
Published: 2008

44. The pulsation modes of the pre-white dwarf PG 1159-035

Author: J. E. S. Costa, W. Ogloza, R. Kalytis, T. J. Ahrens, Anjum S. Mukadam, Souza Oliveira Kepler, S. A. Good, J. Larrison, Albert D. Grauer, E. W. Klumpe, Gerald Handler, Donald E Winget, R. Rosen, H. Lee, P. Martinez, Encarni Romero-Colmenero, O. Giovannini, Matt A. Wood, F. Johannessen, M. C. Akan, R. Janulis, Brian Warner, G. Viraghalmy, X. J. Jiang, Michael H. Montgomery, M. Vuckovic, Leandro Gabriel Althaus, T. Sullivan, M. S. O'Brien, N. Dolez, J.-E. Solheim, Denis J. Sullivan, E. G. Meištas, Fergal Mullally, A. F. M. Costa, A. V. Sergeev, Andrzej S. Baran, M. Paparó, Stanisław Zoła, S. Seetha, Judith L. Provencal, Matthew R. Burleigh, J. C. Clemens, Paul A. Bradley, Antonio Kanaan, Travis S. Metcalfe, Stefan Dreizler, J. L. Deetjen, Jian-Ning Fu, Harry L. Shipman, R. E. Nather, T. Lawrence, Jurek Krzesinski, Steven D. Kawaler, J. M. Gonzalez Perez, A. Ulla, Kazuhiro Sekiguchi, Martin A. Barstow, B. N. Ashoka, S. L. Kim, Alejandro H. Córsico, Reed Riddle, Nicole M. Silvestri, Thorsten Nagel, S. Marinoni, Ö. Hürkal, Sonja Schuh, G. Vauclair, E. Pakštienė, Roberto Silvotti, D. O'Donoghue, M. Chevreton, R. Crowe, Atsuko Nitta, Scot Kleinman, Ömür Çakırlı, Mukremin Kilic, Centro de Fìsica Atòmica (CFA), Universidade de Lisboa (ULISBOA), Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Department of Molecular Microbiology and Biotechnology, Tel Aviv University [Tel Aviv], Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Department of Electronic and Electrical Engineering, Pohang University of Science and Technology (POSTECH), Institute of Applied Physics of RAS, Russian Academy of Sciences [Moscow] (RAS), Department of Physics and Astronomy [Ames, Iowa], Iowa State University (ISU), University of Waterloo [Waterloo], Ege Üniversitesi, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Universidade de Lisboa = University of Lisbon (ULISBOA), Tel Aviv University (TAU), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Rotation period, Astrofísica, Ciencias Astronómicas, 010504 meteorology & atmospheric sciences, individual: PG 1159-035 [Stars], Ciencias Físicas, stars:evolution, stars:white dwarfs, Astrophysics, stars: interiors, 01 natural sciences, stars: individual: PG 1159-035, purl.org/becyt/ford/1 [https], Gravitation, stars:oscillations, asteroseismology: general, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Multiplet, Physics, Solar mass, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], stars: white dwarfs, Astrophysics (astro-ph), stars : white dwarfs, Radius, Magnetic field, Pulsacoes estelares, stars : interiors, Astrophysics::Earth and Planetary Astrophysics, stars: oscillations, CIENCIAS NATURALES Y EXACTAS, Convection, Oscillations, PG 1159-035 (estrella), oscillations [Stars], FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, stars : oscillations, white dwarfs [Stars], [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, stars : individual : PG 1159-035, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, interiors [Stars], White dwarf, White dwarfs, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], VDP::Mathematics and natural science: 400::Physics: 430::Astrophysics, astronomy: 438, Astronomía, Interior stars, white dwarfs: individual( GD358), 13. Climate action, Space and Planetary Science, Oscilacoes, Anãs brancas, oscillations, stars: individual, PG 1159-035, stars: white dwarfs [stars], Interior estelar
Abstract: Context. PG 1159-035, a pre-white dwarf with Teff ≃ 140000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to measure the stellar mass, the rotational period and the inclination of the rotation axis, to estimate an upper limit for the magnetic field, and even to obtain information about the inner stratification of the star. Aims. We have three principal aims: to increase the number of detected and identified pulsation modes in PG 1159-035, study trapping of the star's pulsation modes, and to improve or constrain the determination of stellar parameters. Methods. We used all available WET photometric data from 1983, 1985, 1989. 1993 and 2002 to identify the pulsation periods. Results. We identified 76 additional pulsation modes, increasing to 198 the number of known pulsation modes in PG 1159-035, the largest number of modes detected in any star besides the Sun. From the period spacing we estimated a mass M/M⊙= 0.59 ±0.02 for PG 1159-035, with the uncertainty dominated by the models, not the observation. Deviations in the regular period spacing suggest that some of the pulsation modes are trapped, even though the star is a pre-white dwarf and the gravitational settling is ongoing. The position of the transition zone that causes the mode trapping was calculated at rc/R* = 0.83 ± 0.05. From the multiplet splitting, we calculated the rotational period Prot = 1.3920 ± 0.0008 days and an upper limit for the magnetic field, B < 2000 G. The total power of the pulsation modes at the stellar surface changed less than 30% for ℓ = 1 modes and less than 50% for ℓ = 2 modes. We find no evidence of linear combinations between the 198 pulsation mode frequencies. PG 1159-035 models have not significative convection zones, supporting the hypothesis that nonlinearity arises in the convection zones in cooler pulsating white dwarf stars., La lista completa de autores que integran el documento puede consultarse en el archivo., Facultad de Ciencias Astronómicas y Geofísicas, Instituto de Astrofísica de La Plata
Published: 2008

45. Nonrigid Registration of Brain MRI Using NURBS

Author: Jianzhe Wang, Tianzi Jiang, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: Computer science, Multiresolution analysis, Physics::Medical Physics, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Image registration, Image processing, 02 engineering and technology, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Multigrid method, Artificial Intelligence, 0202 electrical engineering, electronic engineering, information engineering, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Computer vision, ComputingMethodologies_COMPUTERGRAPHICS, business.industry, B-spline, Nonrigid registration, Real image, Computer Science::Graphics, NURBS, Feature (computer vision), Computer Science::Computer Vision and Pattern Recognition, Free-Form Deformations, Signal Processing, 020201 artificial intelligence & image processing, Computer Vision and Pattern Recognition, Artificial intelligence, Focus (optics), business, Software
Abstract: The focus of medical image registration has shifted to nonrigid registration. It is also a core component in computational neuroanatomy. In this paper, we propose an efficient registration framework which has feature of multiresolution and multigrid. In contrast to the existing registration algorithms. Free-Form Deformations based NURBS (Nonuniform Rational B Spline) are used to acquire nonrigid transformation. This can provide a competitive alternative to Free-Form Deformations based B spline on flexibility and accuracy. To our knowledge, it is the first report of the use of this mathematical tool for medical image registration. Subdivision of NURBS is extended to 3D and is used in hierarchical optimization to speed up the registration and avoid local minima. The performance of this method is numerically evaluated on simulated images and real images. Compared with the registration method using uniform Free-Form Deformations based B spline, our method can successfully register images with improved performance.
Published: 2007

46. Microphytoplankton diversity curves of the Chinese Ordovician

Author: Kui Yan, Jun Li, Thomas Servais, Wenbo Su, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), ECE, University of Arizona, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences [Changchun Branch] (CAS), Chinese Academy of Sciences [Beijing] (CAS), Laboratoire de paléontologie et paleogéographie du paleozoique (LPPP), Université de Lille, Sciences et Technologies-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Geologie und Mineralogie, Universität Erlangen-Nürnberg, Netter, Régine, School of the Earth Sciences and Resources [Beijing], China University of Geosciences [Beijing], Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), and Avelin, Herve
Subjects: 010506 paleontology, Acritarchs, China, South china, [SDV]Life Sciences [q-bio], Ordovician, Acritarch, Geology, 010502 geochemistry & geophysics, 01 natural sciences, Katian, [SDV] Life Sciences [q-bio], Paleontology, Sea-level curve, Sea level change, 14. Life underwater, [SDU.STU.PG] Sciences of the Universe [physics]/Earth Sciences/Paleontology, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Sea level, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Diversity (business)
Abstract: Following the publication of a regional diversity curve of the Ordovician organic-walled microphytoplankton (acritarchs) from the Yangtze Platform at the species level [Servais et al., 2004], a diversity curve for China is here presented using all literature data at the generic level. The Chinese curve is a compilation of three separate curves from the three major continental blocks that constituted China in the Ordovician: South China (including the Yangtze Platform), Tarim and North China. The diversity changes can partly be related to sea level changes, both at a regional (South Chinese sea level curve) and at a global level (global curve). The totalised curve for all Chinese localities indicates peaks in diversity that apparently correspond to three sea level highstands at a global level at the early-middle Ordovician boundary (middle “Arenigian”), at the Sandbian-Katian boundary (middle “Caradocian”) and during the Upper Katian (pre-Hirnantian “Ashgillian”) Boda Event [Fortey and Cocks, 2005].
Published: 2007

47. Diffusion Tensor Tractography Based Group Mapping of the Pyramidal Tract in Relapsing-remitting Multiple Sclerosis Patients

Author: Lin, Fuchun, Yu, Chunshui, Jiang, Tianzi, Li, Kuncheng, Chan, Piu, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences [Beijing] (CUMS), and Publications Liama, Chine
Subjects: [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Published: 2007

48. Characterizing Anatomical Differences in Boys with Attention Deficit Hyperactivity Disorder Using Deformation Based Morphometry

Author: Wang, Jianzhe, Jiang, Tianzi, Cao, Qingjiu, Wang, Yufeng, Publications Liama, Chine, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)
Subjects: [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging
Published: 2007

49. Discriminative analysis of early Alzheimer's disease based on two intrinsically anti-correlated networks with resting-state fMRI

Author: Zhening Liu, Kun Wang, Meng Liang, Lixia Tian, Tianzi Jiang, Xinqing Zhang, Liang Wang, Kuncheng Li, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), National Laboratory of Pattern Recognition [Beijing] (NLPR), Institute of Automation - Chinese Academy of Sciences, Department of Radiology, Xuanwu Hospital of Capital-University of Medical Sciences / Beijing, Department of Neurology, JR. Larsen, M. Nielsen, and and J. Sporring
Subjects: Blood-oxygen-level dependent, medicine.diagnostic_test, Resting state fMRI, Computer science, Feature vector, Functional connectivity, Speech recognition, 05 social sciences, Linear classifier, 050105 experimental psychology, Cross-validation, 03 medical and health sciences, 0302 clinical medicine, Discriminative model, medicine, Feature (machine learning), [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, 0501 psychology and cognitive sciences, Functional magnetic resonance imaging, 030217 neurology & neurosurgery
Abstract: In this work, we proposed a discriminative model of Alzheimer's disease (AD) on the basis of multivariate pattern classification and functional magnetic resonance imaging (fMRI). This model used the correlation/anti-correlation coefficients of two intrinsically anti-correlated networks in resting brains, which have been suggested by two recent studies, as the feature of classification. Pseudo-Fisher Linear Discriminative Analysis (pFLDA) was then performed on the feature space and a linear classifier was generated. Using leave-one-out (LOO) cross validation, our results showed a correct classification rate of 83%. We also compared the proposed model with another one based on the whole brain functional connectivity. Our proposed model outperformed the other one significantly, and this implied that the two intrinsically anti-correlated networks may be a more susceptible part of the whole brain network in the early stage of AD.
Published: 2006

50. An Embedding Framework for Myocardial Velocity Field Mapping with MRI

Author: Cong, Longfei, Lee, Su-Lin, Huntbatch, Andrew, Jiang, Tianzi, Yang, Guang-Zhong, Brain imaging (LIAMA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Chinese Academy of Sciences [Changchun Branch] (CAS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institute of Automation - Chinese Academy of Sciences-Centre National de la Recherche Scientifique (CNRS), National Laboratory of Pattern Recognition [Beijing] (NLPR), Institute of Automation - Chinese Academy of Sciences, Medical Image Computing Laboratory, Department of Computing, Imperial College London, and Guang-ZhongYang and Tianzi Jiang and Dinggang Shen and Lixu Gu and Jie Yang
Subjects: Physics::Medical Physics, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging
Abstract: This paper presents an embedding framework for myocardial velocity processing with MRI based on a hollow, semi-spherical template. The relationship between vector bundle and manifold mapping is analysed and three different mapping methods that include tangent mapping, normal mapping, and normal-tangent mapping are assessed for their practical value of myocardial contractility analysis. The proposed method provides a basis for consistent volume matching and vector correspondence, in addition to the ease of calculating biomechanical indices such as radial, circumferential and longitudinal strain rates without the concern of boundary effects. Detailed analysis results with both synthetic and in vivo MR velocity data sets are provided.
Published: 2006

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