139 results on '"Composite Images"'
Search Results
2. Visual Methodologies for Networked Images: Designing Visualizations for Collaborative Research, Cross-platform Analysis, and Public Participation
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Sabine Niederer and Gabriele Colombo
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Visual methodologies ,Image research ,Information visualization ,Digital methods ,Composite images ,Drawing. Design. Illustration ,NC1-1940 - Abstract
In this paper we present visual methodologies attuned to the networked nature of digital images. First, we describe approaches to image research in which images are not separated from their network, but rather studied en groupe. Here, we contrast approaches that treat images as data, and those that regard images as content. Second, we focus on the production of images for digital research, presenting three of their functions: a) the creation of diagrams that facilitate collaboration in interdisciplinary research teams; b) the use of visualizations for cross-platform image analysis; and c) designing images for public participation. Most importantly, such visualizations are not used to form the esthetic culmination of analytical work, but are rather functional tools for digital research that serve parts of the entire research process, from its formulation and operationalization to the engagement of a broader public.
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- 2019
3. A fully-automated, robust, and versatile algorithm for long-term budding yeast segmentation and tracking.
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Wood, N. Ezgi and Doncic, Andreas
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SINGLE cell proteins , *IMAGE segmentation , *SACCHAROMYCES cerevisiae , *TRACKING algorithms , *YEAST , *ALGORITHMS - Abstract
Live cell time-lapse microscopy, a widely-used technique to study gene expression and protein dynamics in single cells, relies on segmentation and tracking of individual cells for data generation. The potential of the data that can be extracted from this technique is limited by the inability to accurately segment a large number of cells from such microscopy images and track them over long periods of time. Existing segmentation and tracking algorithms either require additional dyes or markers specific to segmentation or they are highly specific to one imaging condition and cell morphology and/or necessitate manual correction. Here we introduce a fully automated, fast and robust segmentation and tracking algorithm for budding yeast that overcomes these limitations. Full automatization is achieved through a novel automated seeding method, which first generates coarse seeds, then automatically fine-tunes cell boundaries using these seeds and automatically corrects segmentation mistakes. Our algorithm can accurately segment and track individual yeast cells without any specific dye or biomarker. Moreover, we show how existing channels devoted to a biological process of interest can be used to improve the segmentation. The algorithm is versatile in that it accurately segments not only cycling cells with smooth elliptical shapes, but also cells with arbitrary morphologies (e.g. sporulating and pheromone treated cells). In addition, the algorithm is independent of the specific imaging method (bright-field/phase) and objective used (40X/63X/100X). We validate our algorithm’s performance on 9 cases each entailing a different imaging condition, objective magnification and/or cell morphology. Taken together, our algorithm presents a powerful segmentation and tracking tool that can be adapted to numerous budding yeast single-cell studies. [ABSTRACT FROM AUTHOR]
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- 2019
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4. 'Cheese' and Don't Move! Tame Animals and Contrived Poses: Rob Macinnis's Animal Group Portraits.
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Schwärzler, Monika
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PHOTOGRAPHS ,PHOTOGRAPHY of animals ,AESTHETICS ,PORTRAITS ,CAMERAS - Abstract
Macinnis' photographs of various groups of animals are so striking because all the animals assembled in front of the camera seem to be most willing to accept the camera's gaze and the power relation implied. Animals are usually hard to photograph, because they are not particularly collaborative, unpredictable in their movements, and tend to flee the frame. Macinnis' protagonists pose and look straight into the camera. They appear tame, pacified, 'civil', patiently awaiting their pictorial equivalent. As in all well-managed and representative group photos, there are no obvious signs of disorder or potential subversion. Macinnis' patchwork families look friendly and demonstrate unity and a sense of aesthetic order. Macinnis' photos allow for a reflection on group photographs and their specific arrangements. At the same time, they make one painfully aware of the disciplinary nature of the photographic act. Posing and freezing in front of the camera is a cultural practice that had to be trained and appropriated. Narratives from the beginnings of photography prove that. By looking at Macinnis' fully disciplined animal models, one realizes how much of our own unruliness we had to give up to fit into the photographic system. [ABSTRACT FROM AUTHOR]
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- 2019
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5. METODOLOGÍAS VISUALES para IMÁGENES CONEC TADAS en RED: DISEÑO de VISUALIZACIONES para la INVESTIGACIÓN COLABORATIVA, el ANÁLISIS MULTIPLATAFORMA y la PARTICIPACIÓN PÚBLICA.
- Author
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NIEDERER, SABINE and COLOMBO, GABRIELE
- Abstract
Copyright of Revista Disena is the property of Revista Disena and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
6. Supervised spatial classification of multispectral LiDAR data in urban areas.
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Huo, Lian-Zhi, Silva, Carlos Alberto, Klauberg, Carine, Mohan, Midhun, Zhao, Li-Jun, Tang, Ping, and Hudak, Andrew Thomas
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LIDAR , *METROPOLITAN areas , *LAND cover , *MULTISPECTRAL imaging , *DIGITAL elevation models - Abstract
Multispectral LiDAR (light detection and ranging) data have been initially used for land cover classification. However, there are still high classification uncertainties, especially in urban areas, where objects are often mixed and confounded. This study investigated the efficiency of combining advanced statistical methods and LiDAR metrics derived from multispectral LiDAR data for improving land cover classification accuracy in urban areas. The study area is located in Oshawa, Ontario, Canada, on the Lake Ontario shoreline. Multispectral Optech Titan LiDAR data over the study area were acquired on 3 September 2014 in a single strip of 3 km2. Using the channels at 1,550 nm (C1), 1,064 nm (C2) and 532 nm (C3), LiDAR intensity data, normalized digital surface model (nDSM), pseudo normalized difference vegetation index (PseudoNDVI), morphological profiles (MP), and a novel hierarchical morphological profiles (HMP) were derived and used as features for the classification. A support vector machine classifier with a radial basis function (RBF) kernel was applied in the classification stage, where the optimal parameters for the classifier were selected by a grid search procedure. The combination of intensity, pseudoNDVI, nDSM and HMP resulted in the best land cover classification, with an overall accuracy of 93.28%. [ABSTRACT FROM AUTHOR]
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- 2018
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7. fMRI repetition suppression reveals no sensitivity to trait judgments from faces in face perception or theory-of-mind networks.
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Butler, Emily E., Ward, Rob, Downing, Paul E., and Ramsey, Richard
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FUNCTIONAL magnetic resonance imaging , *IMMUNOSUPPRESSION , *BIOLOGICAL neural networks , *NEUROBIOLOGY , *FACIAL expression - Abstract
The human face cues a wealth of social information, but the neural mechanisms that underpin social attributions from faces are not well known. In the current fMRI experiment, we used repetition suppression to test the hypothesis that populations of neurons in face perception and theory-of-mind neural networks would show sensitivity to faces that cue distinct trait judgments. Although faces were accurately discriminated based on associated traits, our results showed no evidence that face or theory-of-mind networks showed repetition suppression for face traits. Thus, we do not provide evidence for population coding models of face perception that include sensitivity to high and low trait features. Due to aspects of the experimental design, which bolstered statistical power and sensitivity, we have reasonable confidence that we could detect effects of a moderate size, should they exist. The null findings reported here, therefore, add value to models of neural organisation in social perception by showing instances where effects are absent or small. To test the generalisability of our findings, future work should test different types of trait judgment and different types of facial stimuli, in order to further probe the neurobiological bases of impression formation based on facial appearance. [ABSTRACT FROM AUTHOR]
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- 2018
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8. Clinical diagnosis of partial or complete anterior cruciate ligament tears using patients' history elements and physical examination tests.
- Author
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Décary, Simon, Fallaha, Michel, Belzile, Sylvain, Martel-Pelletier, Johanne, Pelletier, Jean-Pierre, Feldman, Debbie, Sylvestre, Marie-Pierre, Vendittoli, Pascal-André, and Desmeules, François
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ANTERIOR cruciate ligament injury diagnosis , *PERIODIC health examinations , *ORTHOPEDIC surgery , *PHYSICIANS , *LACHMAN test - Abstract
Objective: To assess the diagnostic validity of clusters combining history elements and physical examination tests to diagnose partial or complete anterior cruciate ligament (ACL) tears. Design: Prospective diagnostic study. Settings: Orthopaedic clinics (n = 2), family medicine clinics (n = 2) and community-dwelling. Participants: Consecutive patients with a knee complaint (n = 279) and consulting one of the participating orthopaedic surgeons (n = 3) or sport medicine physicians (n = 2). Interventions: Not applicable. Main outcome measures: History elements and physical examination tests performed independently were compared to the reference standard: an expert physicians’ composite diagnosis including history elements, physical tests and confirmatory magnetic resonance imaging. Penalized logistic regression (LASSO) was used to identify history elements and physical examination tests associated with the diagnosis of ACL tear and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures including sensitivity (Se), specificity (Sp), predictive values and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CI) were calculated. Results: Forty-three individuals received a diagnosis of partial or complete ACL tear (15.4% of total cohort). The Lachman test alone was able to diagnose partial or complete ACL tears (LR+: 38.4; 95%CI: 16.0–92.5). Combining a history of trauma during a pivot with a “popping” sensation also reached a high diagnostic validity for partial or complete tears (LR+: 9.8; 95%CI: 5.6–17.3). Combining a history of trauma during a pivot, immediate effusion after trauma and a positive Lachman test was able to identify individuals with a complete ACL tear (LR+: 17.5; 95%CI: 9.8–31.5). Finally, combining a negative history of pivot or a negative popping sensation during trauma with a negative Lachman or pivot shift test was able to exclude both partial or complete ACL tears (LR-: 0.08; 95%CI: 0.03–0.24). Conclusion: Diagnostic clusters combining history elements and physical examination tests can support the differential diagnosis of ACL tears compared to various knee disorders. [ABSTRACT FROM AUTHOR]
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- 2018
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9. Negative body image: Relationships with heightened disgust propensity, disgust sensitivity, and self-directed disgust.
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Spreckelsen, Paula von, Glashouwer, Klaske A., Bennik, Elise C., Wessel, Ineke, and de Jong, Peter J.
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BODY image , *MIND & body , *SELF-perception , *AVERSION , *DISPOSITION (Philosophy) - Abstract
Consistent with the view that disgust might be involved in persistent body dissatisfaction, there is preliminary evidence showing a positive correlation between measures of negative body image and indices of both trait disgust and self-directed disgust. In two correlational studies among undergraduates (N = 577 and N = 346, respectively) we aimed at replicating and extending these findings by testing a series of critical relationships, which follow from our hypotheses that 1) trait disgust propensity would increase the risk of developing a negative body image by increasing the likelihood of feeling self-disgust, and 2) trait disgust sensitivity would heighten the impact of self-disgust on the development of persistent negative body appraisals. Replicating previous research, both studies showed that negative body image was positively related to self-disgust, disgust propensity and disgust sensitivity. Mediation analyses showed that, in line with our model, self-disgust partly accounted for the association between disgust propensity and negative body image. Although disgust sensitivity showed an independent relationship with body image, disgust sensitivity did not moderate the association between self-disgust and negative body image. All in all, findings are consistent with the view that self-disgust-induced avoidance may contribute to persistent negative body appraisals. [ABSTRACT FROM AUTHOR]
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- 2018
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10. Preparation and characterization of Fe3O4@Au-C225 composite targeted nanoparticles for MRI of human glioma.
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Ge, Yaoqi, Zhong, Yuejiao, Ji, Guozhong, Lu, Qianling, Dai, Xinyu, Guo, Zhirui, Zhang, Peng, Peng, Gang, Zhang, Kangzhen, and Li, Yuntao
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IRON oxide nanoparticles , *GLIOMAS , *MAGNETIC resonance imaging , *NANOPARTICLES , *IMMUNOASSAY , *DIAGNOSIS , *THERAPEUTICS - Abstract
Objective: To study the characterization of Fe3O4@Au-C225 composite targeted MNPs. Methods: Fe3O4@Au-C225 was prepared by the absorption method. The immunosorbent assay was used to evaluate its absorption efficiency at C225 Fc. ZETA SIZER3000 laser particle size analyzer, ultraviolet photometer and its characteristics were analyzed by VSM. the targeting effect of Fe3O4@Au-C225 composite targeted MNPs on U251 cells in vitro were detected by 7.0 Tesla Micro-MR; and subcutaneous transplanted human glioma in nude mice were performed the targeting effect in vivo after tail vein injection of Fe3O4@Au-C225 composite targeted MNPs by MRI. Results: The self-prepared Fe3O4@Au composite MNPs can adsorb C225 with high efficiency of adsorption so that Fe3O4@Au-C225 composite targeted MNPs were prepared successfully. Fe3O4@Au-C225 composite targeted MNPs favorably targeted human glioma cell line U251 in vitro; Fe3O4@Au-C225 composite targeted MNPs have good targeting ability to xenografted glioma on nude mice in vivo, and can be traced by MRI. Conclusion: The Fe3O4@Au-C225 composite targeted MNPs have the potential to be used as a tracer for glioma in vivo. [ABSTRACT FROM AUTHOR]
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- 2018
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11. Progressive derivation of serially homologous neuroblast lineages in the gnathal CNS of Drosophila.
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Rickert, Christof, Lüer, Karin, Vef, Olaf, and Technau, Gerhard M.
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CENTRAL nervous system , *DROSOPHILA melanogaster , *NEURAL stem cells , *INSECT genetics , *GENE expression , *INSECT morphology - Abstract
Along the anterior-posterior axis the central nervous system is subdivided into segmental units (neuromeres) the composition of which is adapted to their region-specific functional requirements. In Drosophila melanogaster each neuromere is formed by a specific set of identified neural stem cells (neuroblasts, NBs). In the thoracic and anterior abdominal region of the embryonic ventral nerve cord segmental sets of NBs resemble the ground state (2nd thoracic segment, which does not require input of homeotic genes), and serial (segmental) homologs generate similar types of lineages. The three gnathal head segments form a transitional zone between the brain and the ventral nerve cord. It has been shown recently that although all NBs of this zone are serial homologs of NBs in more posterior segments, they progressively differ from the ground state in anterior direction (labial > maxillary > mandibular segment) with regard to numbers and expression profiles. To study the consequences of their derived characters we traced the embryonic lineages of gnathal NBs using the Flybow and DiI-labelling techniques. For a number of clonal types serial homology is rather clearly reflected by their morphology (location and projection patterns) and cell specific markers, despite of reproducible segment-specific differences. However, many lineages, particularly in the mandibular segment, show a degree of derivation that impedes their assignment to ground state serial homologs. These findings demonstrate that differences in gene expression profiles of gnathal NBs go along with anteriorly directed progressive derivation in the composition of their lineages. Furthermore, lineage sizes decrease from labial to mandibular segments, which in concert with decreasing NB-numbers lead to reduced volumes of gnathal neuromeres, most significantly in the mandibular segment. [ABSTRACT FROM AUTHOR]
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- 2018
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12. Semi-automated digital measurement as the method of choice for beta cell mass analysis.
- Author
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Coppens, Violette, Leuckx, Gunter, Heremans, Yves, Staels, Willem, Verdonck, Yannick, Baeyens, Luc, De Leu, Nico, and Heimberg, Harry
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PANCREATIC beta cells , *CELL differentiation , *CELL proliferation , *CELL size , *DIGITAL image processing - Abstract
Pancreas injury by partial duct ligation (PDL) activates beta cell differentiation and proliferation in adult mouse pancreas but remains controversial regarding the anticipated increase in beta cell volume. Several reports unable to show beta cell volume augmentation in PDL pancreas used automated digital image analysis software. We hypothesized that fully automatic beta cell morphometry without manual micrograph artifact remediation introduces bias and therefore might be responsible for reported discrepancies and controversy. However, our present results prove that standard digital image processing with automatic thresholding is sufficiently robust albeit less sensitive and less adequate to demonstrate a significant increase in beta cell volume in PDL versus Sham-operated pancreas. We therefore conclude that other confounding factors such as quality of surgery, selection of samples based on relative abundance of the transcription factor Neurogenin 3 (Ngn3) and tissue processing give rise to inter-laboratory inconsistencies in beta cell volume quantification in PDL pancreas. [ABSTRACT FROM AUTHOR]
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- 2018
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13. Effect of intra-articular administration of superparamagnetic iron oxide nanoparticles (SPIONs) for MRI assessment of the cartilage barrier in a large animal model.
- Author
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Labens, Raphael, Daniel, Carola, Hall, Sarah, Xia, Xin-Rui, and Schwarz, Tobias
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MAGNETIC resonance imaging , *SUPERPARAMAGNETIC materials , *IRON oxides , *CHEMOTACTIC factors , *NEUTROPHILS - Abstract
Early diagnosis of cartilage disease at a time when changes are limited to depletion of extracellular matrix components represents an important diagnostic target to reduce patient morbidity. This report is to present proof of concept for nanoparticle dependent cartilage barrier imaging in a large animal model including the use of clinical magnetic resonance imaging (MRI). Conditioned (following matrix depletion) and unconditioned porcine metacarpophalangeal cartilage was evaluated on the basis of fluorophore conjugated 30 nm and 80 nm spherical gold nanoparticle permeation and multiphoton laser scanning and bright field microscopy after autometallographic particle enhancement. Consequently, conditioned and unconditioned joints underwent MRI pre- and post-injection with 12 nm superparamagnetic iron oxide nanoparticles (SPIONs) to evaluate particle permeation in the context of matrix depletion and use of a clinical 1.5 Tesla MRI scanner. To gauge the potential pro-inflammatory effect of intra-articular nanoparticle delivery co-cultures of equine synovium and cartilage tissue were exposed to an escalating dose of SPIONs and IL-6, IL-10, IFN-γ and PGE2 were assessed in culture media. The chemotactic potential of growth media samples was subsequently assessed in transwell migration assays on isolated equine neutrophils. Results demonstrate an increase in MRI signal following conditioning of porcine joints which suggests that nanoparticle dependent compositional cartilage imaging is feasible. Tissue culture and neutrophil migration assays highlight a dose dependent inflammatory response following SPION exposure which at the imaging dose investigated was not different from controls. The preliminary safety and imaging data support the continued investigation of nanoparticle dependent compositional cartilage imaging. To our knowledge, this is the first report in using SPIONs as intra-articular MRI contrast agent for studying cartilage barrier function, which could potentially lead to a new diagnostic technique for early detection of cartilage disease. [ABSTRACT FROM AUTHOR]
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- 2017
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14. Nasmehnite se in stojte pri miru! Krotke živali in načrtna poziranja: Skupinski portreti živali Roba Macinnisa.
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Schwärzler, Monika
- Abstract
Copyright of Revija Fotografija / Membrana: Revija o Fotografiji, Teoriji in Vizualni Kulturi is the property of Membrana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
15. Rave against the (vision) machine
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Fourmentraux, Jean-Paul, Centre Norbert Elias (CNELIAS), École des hautes études en sciences sociales (EHESS)-Avignon Université (AU)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Aix-Marseille Université - Faculté des Arts, Lettres, Langues et Sciences Humaines (AMU ALLSH), and Aix Marseille Université (AMU)
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Machines de vision ,Surveillance ,Agonistic devices ,Digital art ,Design critique ,Images composites ,Vision machines ,Médias tactiques ,Facial recognition ,Technologies ,[SHS.ART]Humanities and Social Sciences/Art and art history ,[SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology ,Dispositifs agonistiques ,Tactical media ,Art numérique ,Monde numérique ,Reconnaissance faciale ,Critical design ,Collective interactivity and interaction ,Interactivité et interaction collectives ,Composite images - Abstract
International audience; An agonistic relationship to image and technology marks the works of the artist Samuel Bianchini. The singularity of his approach lies in the repeated and ritualistic staging of a confrontation with seeing. This text analyzes the experience of Discontrol Party (2009-2018), an interactive and festive counter-device developed in the framework of a research on collective interaction (Large Group Interaction) at EnsadLab/DRii, a laboratory of the École nationale supérieure des Arts Décoratifs (Paris). The artwork stages "vision machines", an empire of surveillance that is also a "theater of operations" for the public, confronted with the proliferation of composite images: diagrams, graphs, units of measurement, clouds of points, tables of data. What is the meaning of these images, which are also data? Can we see in them the will of a totalitarian representation and the promise of a total transparency of the human experience? Should we be happy about it? Should we be alarmed? Is it possible to bug these digital detection systems? There is no doubt that this is a question of power relations, and we have the right to ask ourselves which of the human or the machine is the master or the slave.; Un rapport agonistique à l’image et à la technologie marque les réalisations de l’artiste Samuel Bianchini. La singularité de son approche réside dans la mise en scène répétée et rituelle d’une confrontation avec le voir. Ce texte analyse l’expérience de Discontrol Party (2009-2018), un contre-dispositif interactif et festif développé dans le cadre d’une recherche sur l’interaction collective (Large Group Interaction) à l’EnsadLab/DRii, laboratoire de l’École nationale supérieure des Arts Décoratifs (Paris). L’oeuvre met en scène des « machines de vision », un empire de la surveillance qui est aussi un théâtre d’opérations pour le public, confronté à la prolifération d’images composites : diagrammes, graphiques, unités de mesures, nuages de points, tableaux de données. Quel est le sens de ces images qui sont aussi des datas ? Peut-on y voir la volonté d’une représentation totalitaire et la promesse d’une transparence totale de l’expérience humaine ? Doit-on s’en réjouir ? S’en alarmer ? Est-il possible de faire bugger ces systèmes numériques de détection ? Nul doute qu’il puisse être question ici d’un rapport de force, face auquel on serait en droit de se demander lequel de l’humain ou de la machine est le maître et l’esclave.
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- 2022
16. Influence of main forcing affecting the Tagus turbid plume under high river discharges using MODIS imagery.
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Fernández-Nóvoa, D., Gómez-Gesteira, M., Mendes, R., deCastro, M., Vaz, N., and Dias, J. M.
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REGIONS of freshwater influence , *MODIS (Spectroradiometer) , *ARTIFICIAL satellites , *TURBIDITY - Abstract
The role of river discharge, wind and tide on the extension and variability of the Tagus River plume was analyzed from 2003 to 2015. This study was performed combining daily images obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor located onboard the Aqua and Terra satellites. Composites were generated by averaging pixels with the same forcing conditions. River discharge shows a strong relation with the extension of the Tagus plume. The plume grows with the increasing river discharge and express a two day lag caused by the long residence time of water within the estuary. The Tagus turbid plume was found to be smaller under northerly and easterly winds, than under southerly and westerly winds. It is suggested that upwelling favoring winds provoke the offshore movement of the plume material with a rapidly decrease in turbidity values whereas downwelling favoring winds retain plume material in the north coast close to the Tagus mouth. Eastern cross-shore (oceanward) winds spread the plume seaward and to the north following the coast geometry, whereas western cross-shore (landward) winds keep the plume material in both alongshore directions occupying a large part of the area enclosed by the bay. Low tides produce larger and more turbid plumes than high tides. In terms of fortnightly periodicity, the maximum plume extension corresponding to the highest turbidity is observed during and after spring tides. Minimum plume extension associated with the lowest turbidity occurs during and after neap tides. [ABSTRACT FROM AUTHOR]
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- 2017
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17. Distribution and drivers of global mangrove forest change, 1996–2010.
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Thomas, Nathan, Lucas, Richard, Bunting, Peter, Hardy, Andrew, Rosenqvist, Ake, and Simard, Marc
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MANGROVE plants , *LAND cover , *SYNTHETIC aperture radar , *REMOTE sensing by radar , *ANTHROPOGENIC effects on nature - Abstract
For the period 1996-2010, we provide the first indication of the drivers behind mangrove land cover and land use change across the (pan-)tropics using time-series Japanese Earth Resources Satellite (JERS-1) Synthetic Aperture Radar (SAR) and Advanced Land Observing Satellite (ALOS) Phased Array-type L-band SAR (PALSAR) data. Multi-temporal radar mosaics were manually interpreted for evidence of loss and gain in forest extent and its associated driver. Mangrove loss as a consequence of human activities was observed across their entire range. Between 1996-2010 12% of the 1168 1°x1° radar mosaic tiles examined contained evidence of mangrove loss, as a consequence of anthropogenic degradation, with this increasing to 38% when combined with evidence of anthropogenic activity prior to 1996. The greatest proportion of loss was observed in Southeast Asia, whereby approximately 50% of the tiles in the region contained evidence of mangrove loss, corresponding to 18.4% of the global mangrove forest tiles. Southeast Asia contained the greatest proportion (33.8%) of global mangrove forest. The primary driver of anthropogenic mangrove loss was found to be the conversion of mangrove to aquaculture/agriculture, although substantial advance of mangroves was also evident in many regions. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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18. Automated analysis of co-localized protein expression in histologic sections of prostate cancer.
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Tennill, Thomas A., Gross, Mitchell E., and Frieboes, Hermann B.
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PROSTATE cancer , *IMMUNOHISTOCHEMISTRY , *PROTEIN expression , *DNA microarrays , *MICROSCOPY - Abstract
An automated approach based on routinely-processed, whole-slide immunohistochemistry (IHC) was implemented to study co-localized protein expression in tissue samples. Expression of two markers was chosen to represent stromal (CD31) and epithelial (Ki-67) compartments in prostate cancer. IHC was performed on whole-slide sections representing low-, intermediate-, and high-grade disease from 15 patients. The automated workflow was developed using a training set of regions-of-interest in sequential tissue sections. Protein expression was studied on digital representations of IHC images across entire slides representing formalin-fixed paraffin embedded blocks. Using the training-set, the known association between Ki-67 and Gleason grade was confirmed. CD31 expression was more heterogeneous across samples and remained invariant with grade in this cohort. Interestingly, the Ki-67/CD31 ratio was significantly increased in high (Gleason ≥ 8) versus low/intermediate (Gleason ≤7) samples when assessed in the training-set and the whole-tissue block images. Further, the feasibility of the automated approach to process Tissue Microarray (TMA) samples in high throughput was evaluated. This work establishes an initial framework for automated analysis of co-localized protein expression and distribution in high-resolution digital microscopy images based on standard IHC techniques. Applied to a larger sample population, the approach may help to elucidate the biologic basis for the Gleason grade, which is the strongest, single factor distinguishing clinically aggressive from indolent prostate cancer. [ABSTRACT FROM AUTHOR]
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- 2017
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19. Estimating changes in lichen mat volume through time and related effects on barren ground caribou (Rangifer tarandus groenlandicus) movement.
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Rickbeil, Gregory J. M., Hermosilla, Txomin, Coops, Nicholas C., White, Joanne C., and Wulder, Michael A.
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BARREN ground caribou , *LICHENS , *HABITATS , *TROUT cod - Abstract
Lichens form a critical portion of barren ground caribou (Rangifer tarandus groenlandicus) diets, especially during winter months. Here, we assess lichen mat volume across five herd ranges in the Northwest Territories and Nunavut, Canada, using newly developed composite Landsat imagery. The lichen volume estimator (LVE) was adapted for use across 700 000 km2 of barren ground caribou habitat annually from 1984–2012. We subsequently assessed how LVE changed temporally throughout the time series for each pixel using Theil-Sen’s slopes, and spatially by assessing whether slope values were centered in local clusters of similar values. Additionally, we assessed how LVE estimates resulted in changes in barren ground caribou movement rates using an extensive telemetry data set from 2006–2011. The Ahiak/Beverly herd had the largest overall increase in LVE (median = 0.033), while the more western herds had the least (median slopes below zero in all cases). LVE slope pixels were arranged in significant clusters across the study area, with the Cape Bathurst, Bathurst, and Bluenose East herds having the most significant clusters of negative slopes (more than 20% of vegetated land in each case). The Ahiak/Beverly and Bluenose West had the most significant positive clusters (16.3% and 18.5% of vegetated land respectively). Barren ground caribou displayed complex reactions to changing lichen conditions depending on season; the majority of detected associations with movement data agreed with current understanding of barren ground caribou foraging behavior (the exception was an increase in movement velocity at high lichen volume estimates in Fall). The temporal assessment of LVE identified areas where shifts in ecological conditions may have resulted in changing lichen mat conditions, while assessing the slope estimates for clustering identified zones beyond the pixel scale where forage conditions may be changing. Lichen volume estimates associated with barren ground caribou movement metrics in an expected manner and, as such, show value for future habitat assessments. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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20. Multifractal Downscaling of Rainfall Using Normalized Difference Vegetation Index (NDVI) in the Andes Plateau.
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Duffaut Espinosa, L. A., Posadas, A. N., Carbajal, M., and Quiroz, R.
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DOWNSCALING (Climatology) , *NORMALIZED difference vegetation index , *RAINFALL frequencies , *SPATIO-temporal variation , *METEOROLOGICAL stations - Abstract
In this paper, a multifractal downscaling technique is applied to adequately transformed and lag corrected normalized difference vegetation index (NDVI) in order to obtain daily estimates of rainfall in an area of the Peruvian Andean high plateau. This downscaling procedure is temporal in nature since the original NDVI information is provided at an irregular temporal sampling period between 8 and 11 days, and the desired final scale is 1 day. The spatial resolution of approximately 1 km remains the same throughout the downscaling process. The results were validated against on-site measurements of meteorological stations distributed in the area under study. [ABSTRACT FROM AUTHOR]
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- 2017
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21. Multi-Channel Optical Coherence Elastography Using Relative and Absolute Shear-Wave Time of Flight.
- Author
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Elyas, Eli, Grimwood, Alex, Erler, Janine T., Robinson, Simon P., Cox, Thomas R., Woods, Daniel, Clowes, Peter, De Luca, Ramona, Marinozzi, Franco, Fromageau, Jérémie, and Bamber, Jeffrey C.
- Subjects
- *
ELASTOGRAPHY , *SHEAR waves , *TIME-of-flight spectrometry , *CYTOLOGY , *MODULUS of rigidity - Abstract
Elastography, the imaging of elastic properties of soft tissues, is well developed for macroscopic clinical imaging of soft tissues and can provide useful information about various pathological processes which is complementary to that provided by the original modality. Scaling down of this technique should ply the field of cellular biology with valuable information with regard to elastic properties of cells and their environment. This paper evaluates the potential to develop such a tool by modifying a commercial optical coherence tomography (OCT) device to measure the speed of shear waves propagating in a three-dimensional (3D) medium. A needle, embedded in the gel, was excited to vibrate along its long axis and the displacement as a function of time and distance from the needle associated with the resulting shear waves was detected using four M-mode images acquired simultaneously using a commercial four-channel swept-source OCT system. Shear-wave time of arrival (TOA) was detected by tracking the axial OCT-speckle motion using cross-correlation methods. Shear-wave speed was then calculated from inter-channel differences of TOA for a single burst (the relative TOA method) and compared with the shear-wave speed determined from positional differences of TOA for a single channel over multiple bursts (the absolute TOA method). For homogeneous gels the relative method provided shear-wave speed with acceptable precision and accuracy when judged against the expected linear dependence of shear modulus on gelatine concentration (R2 = 0.95) and ultimate resolution capabilities limited by 184μm inter-channel distance. This overall approach shows promise for its eventual provision as a research tool in cancer cell biology. Further work is required to optimize parameters such as vibration frequency, burst length and amplitude, and to assess the lateral and axial resolutions of this type of device as well as to create 3D elastograms. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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22. Quantification of Local Warming Trend: A Remote Sensing-Based Approach.
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Rahaman, Khan Rubayet and Hassan, Quazi K.
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GLOBAL warming , *REMOTE sensing , *MODIS (Spectroradiometer) , *ATMOSPHERIC temperature , *METEOROLOGICAL stations , *CLIMATE change - Abstract
Understanding the warming trends at local level is critical; and, the development of relevant adaptation and mitigation policies at those levels are quite challenging. Here, our overall goal was to generate local warming trend map at 1 km spatial resolution by using: (i) Moderate Resolution Imaging Spectroradiometer (MODIS)-based 8-day composite surface temperature data; (ii) weather station-based yearly average air temperature data; and (iii) air temperature normal (i.e., 30 year average) data over the Canadian province of Alberta during the period 1961–2010. Thus, we analysed the station-based air temperature data in generating relationships between air temperature normal and yearly average air temperature in order to facilitate the selection of year-specific MODIS-based surface temperature data. These MODIS data in conjunction with weather station-based air temperature normal data were then used to model local warming trends. We observed that almost 88% areas of the province experienced warming trends (i.e., up to 1.5°C). The study concluded that remote sensing technology could be useful for delineating generic trends associated with local warming. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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23. Developing Forest Cover Composites through a Combination of Landsat-8 Optical and Sentinel-1 SAR Data for the Visualization and Extraction of Forested Areas
- Author
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Ram C. Sharma, Keitarou Hara, and Ryutaro Tateishi
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forests ,multi-spectral ,Landsat-8 ,Sentinel-1 ,backscattering ,composite images ,neural networks ,Photography ,TR1-1050 ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Mapping the distribution of forested areas and monitoring their spatio-temporal changes are necessary for the conservation and management of forests. This paper presents two new image composites for the visualization and extraction of forest cover. By exploiting the Landsat-8 satellite-based multi-temporal and multi-spectral reflectance datasets, the Forest Cover Composite (FCC) was designed in this research. The FCC is an RGB (red, green, blue) color composite made up of short-wave infrared reflectance and green reflectance, specially selected from the day when the Normalized Difference Vegetation Index (NDVI) is at a maximum, as the red and blue bands, respectively. The annual mean NDVI values are used as the green band. The FCC is designed in such a way that the forested areas appear greener than other vegetation types, such as grasses and shrubs. On the other hand, the croplands and barren lands are usually seen as red and water/snow is seen as blue. However, forests may not necessarily be greener than other perennial vegetation. To cope with this problem, an Enhanced Forest Cover Composite (EFCC) was designed by combining the annual median backscattering intensity of the VH (vertical transmit, horizontal receive) polarization data from the Sentinel-1 satellite with the green term of the FCC to suppress the green component (mean NDVI values) of the FCC over the non-forested vegetative areas. The performances of the FCC and EFCC were evaluated for the discrimination and classification of forested areas all over Japan with the support of reference data. The FCC and EFCC provided promising results, and the high-resolution forest map newly produced in the research provided better accuracy than the extant MODIS (Moderate Resolution Imaging Spectroradiometer) Land Cover Type product (MCD12Q1) in Japan. The composite images proposed in the research are expected to improve forest monitoring activities in other regions as well.
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- 2018
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24. Placental Sequestration of Plasmodium falciparum Malaria Parasites Is Mediated by the Interaction Between VAR2CSA and Chondroitin Sulfate A on Syndecan-1.
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Ayres Pereira, Marina, Mandel Clausen, Thomas, Pehrson, Caroline, Mao, Yang, Resende, Mafalda, Daugaard, Mads, Riis Kristensen, Anders, Spliid, Charlotte, Mathiesen, Line, E. Knudsen, Lisbeth, Damm, Peter, G. Theander, Thor, R. Hansson, Stefan, A. Nielsen, Morten, and Salanti, Ali
- Subjects
- *
PLACENTAL enzymes , *SEQUESTRATION (Chemistry) , *PLASMODIUM falciparum , *CHONDROITIN sulfates , *SYNDECANS - Abstract
During placental malaria, Plasmodium falciparum infected erythrocytes sequester in the placenta, causing health problems for both the mother and fetus. The specific adherence is mediated by the VAR2CSA protein, which binds to placental chondroitin sulfate (CS) on chondroitin sulfate proteoglycans (CSPGs) in the placental syncytium. However, the identity of the CSPG core protein and the cellular impact of the interaction have remain elusive. In this study we identified the specific CSPG core protein to which the CS is attached, and characterized its exact placental location. VAR2CSA pull-down experiments using placental extracts from whole placenta or syncytiotrophoblast microvillous cell membranes showed three distinct CSPGs available for VAR2CSA adherence. Further examination of these three CSPGs by immunofluorescence and proximity ligation assays showed that syndecan-1 is the main receptor for VAR2CSA mediated placental adherence. We further show that the commonly used placental choriocarcinoma cell line, BeWo, express a different set of proteoglycans than those present on placental syncytiotrophoblast and may not be the most biologically relevant model to study placental malaria. Syncytial fusion of the BeWo cells, triggered by forskolin treatment, caused an increased expression of placental CS-modified syndecan-1. In line with this, we show that rVAR2 binding to placental CS impairs syndecan-1-related Src signaling in forskolin treated BeWo cells, but not in untreated cells. [ABSTRACT FROM AUTHOR]
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- 2016
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25. How Did Urban Land Expand in China between 1992 and 2015? A Multi-Scale Landscape Analysis.
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Xu, Min, He, Chunyang, Liu, Zhifeng, and Dou, Yinyin
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- *
LANDSCAPES , *AGGLOMERATION (Materials) , *CITIES & towns ,URBAN ecology (Sociology) - Abstract
Effective and timely quantification of the spatiotemporal pattern of urban expansion in China is important for the assessment of its environmental effects. However, the dynamics of the most recent urban expansions in China since 2012 have not yet been adequately explained due to a lack of current information. In this paper, our objective was to quantify spatiotemporal patterns of urban expansion in China between 1992 and 2015. First, we extracted information on urban expansion in China between 1992 and 2015 by integrating nighttime light data, vegetation index data, and land surface temperature data. Then we analyzed the spatiotemporal patterns of urban expansion at the national and regional scales, as well as at that of urban agglomerations. We found that China experienced a rapid and large-scale process of urban expansion between 1992 and 2015, with urban land increasing from 1.22 × 104 km2 to 7.29 × 104 km2, increasing in size nearly fivefold and with an average annual growth rate of 8.10%, almost 2.5 times as rapid as the global average. We also found that urban land in China expanded mainly by occupying 3.31 × 104 km2 of cropland, which comprised 54.67% of the total area of expanded urban land. Among the three modes of growth—infilling, edge expansion, and leapfrog—edge expansion was the main cause of cropland loss. Cropland loss resulting from edge expansion of urban land totalled 2.51 × 104 km2, accounting for over 75% of total cropland loss. We suggest that effective future management with respect to edge expansion of urban land is needed to protect cropland in China. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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26. ECM-Regulator timp Is Required for Stem Cell Niche Organization and Cyst Production in the Drosophila Ovary.
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Pearson, John R., Zurita, Federico, Tomás-Gallardo, Laura, Díaz-Torres, Alfonsa, Díaz de la Loza, María del Carmen, Franze, Kristian, Martín-Bermudo, María D., and González-Reyes, Acaimo
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STEM cells , *EXTRACELLULAR matrix , *PROTEIN analysis , *HOMEOSTASIS , *METALLOPROTEINASE genetics , *MATHEMATICAL models - Abstract
The extracellular matrix (ECM) is a pivotal component adult tissues and of many tissue-specific stem cell niches. It provides structural support and regulates niche signaling during tissue maintenance and regeneration. In many tissues, ECM remodeling depends on the regulation of MMP (atrix etalloroteinase) activity by inhibitory TIMP (issue nhibitors of metalloproteinases) proteins. Here, we report that the only Drosophila timp gene is required for maintaining the normal organization and function of the germline stem cell niche in adult females. timp mutant ovaries show reduced levels of both Drosophila Collagen IV α chains. In addition, tissue stiffness and the cellular organization of the ovarian niche are affected in timp mutants. Finally, loss of timp impairs the ability of the germline stem cell niche to generate new cysts. Our results demonstrating a crucial role for timp in tissue organization and gamete production thus provide a link between the regulation of ECM metabolism and tissue homeostasis. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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- View/download PDF
27. A benchmark dataset for canopy crown detection and delineation in co-registered airborne RGB, LiDAR and hyperspectral imagery from the National Ecological Observation Network
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Ethan P. White, Sarah J. Graves, Stephanie A. Bohlman, Aditya Singh, Alina Zare, Sergio Marconi, Dylan Stewart, and Ben G. Weinstein
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0106 biological sciences ,0301 basic medicine ,Databases, Factual ,Computer science ,Forests ,01 natural sciences ,Trees ,Remote Sensing ,Geoinformatics ,Image Processing, Computer-Assisted ,Range (statistics) ,Biology (General) ,Lidar ,Remote Sensing Imagery ,Geography ,Ecology ,Applied Mathematics ,Simulation and Modeling ,Optical Imaging ,Crown (botany) ,Eukaryota ,Hyperspectral imaging ,Plants ,Terrestrial Environments ,Benchmarking ,Computational Theory and Mathematics ,Modeling and Simulation ,Physical Sciences ,Benchmark (computing) ,Engineering and Technology ,Algorithms ,Environmental Monitoring ,Research Article ,Computer and Information Sciences ,Forest Ecology ,Imaging Techniques ,QH301-705.5 ,Research and Analysis Methods ,010603 evolutionary biology ,Ecosystems ,GeneralLiterature_MISCELLANEOUS ,Composite Images ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Genetics ,Baseline (configuration management) ,Molecular Biology ,Ecosystem ,Ecology, Evolution, Behavior and Systematics ,Ecology and Environmental Sciences ,Organisms ,Biology and Life Sciences ,030104 developmental biology ,Earth Sciences ,RGB color model ,Scale (map) ,Mathematics - Abstract
Broad scale remote sensing promises to build forest inventories at unprecedented scales. A crucial step in this process is to associate sensor data into individual crowns. While dozens of crown detection algorithms have been proposed, their performance is typically not compared based on standard data or evaluation metrics. There is a need for a benchmark dataset to minimize differences in reported results as well as support evaluation of algorithms across a broad range of forest types. Combining RGB, LiDAR and hyperspectral sensor data from the USA National Ecological Observatory Network’s Airborne Observation Platform with multiple types of evaluation data, we created a benchmark dataset to assess crown detection and delineation methods for canopy trees covering dominant forest types in the United States. This benchmark dataset includes an R package to standardize evaluation metrics and simplify comparisons between methods. The benchmark dataset contains over 6,000 image-annotated crowns, 400 field-annotated crowns, and 3,000 canopy stem points from a wide range of forest types. In addition, we include over 10,000 training crowns for optional use. We discuss the different evaluation data sources and assess the accuracy of the image-annotated crowns by comparing annotations among multiple annotators as well as overlapping field-annotated crowns. We provide an example submission and score for an open-source algorithm that can serve as a baseline for future methods., Author summary Combining RGB, LiDAR and hyperspectral sensor data from the USA National Ecological Observatory Network’s Airborne Observation Platform with multiple types of evaluation data, we created a benchmark dataset to assess crown detection and delineation methods for canopy trees covering dominant forest types in the United States. This benchmark dataset includes an R package to standardize evaluation metrics and simplify comparisons between methods. The benchmark dataset contains over 6,000 image-annotated crowns, 400 field-annotated crowns, and 3,000 canopy stem points from a wide range of forest types.
- Published
- 2021
28. Robust quantitative assessment of collagen fibers with picrosirius red stain and linearly polarized light as demonstrated on atherosclerotic plaque samples
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Sean Madden, Matthew D. Saybolt, Alena Davis, Stephen T. Sum, Robert L. Wilensky, Samantha L. Farrow, Cherry Greiner, Stephanie J. Grainger, and Jimmy Su
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Computer and Information Sciences ,Materials science ,Histology ,Imaging Techniques ,Glaciology ,Science ,Image Analysis ,030204 cardiovascular system & hematology ,Digital Imaging ,Research and Analysis Methods ,Stain ,Composite image filter ,Biochemistry ,Vascular Medicine ,law.invention ,Composite Images ,Grayscale ,03 medical and health sciences ,0302 clinical medicine ,law ,Microscopy ,Medicine and Health Sciences ,Humans ,030304 developmental biology ,0303 health sciences ,Multidisciplinary ,Pixel ,Staining and Labeling ,Linear polarization ,Biology and Life Sciences ,Proteins ,Polarizer ,Polarization (waves) ,Atherosclerosis ,Coronary Vessels ,Plaque, Atherosclerotic ,Visualization ,Ice Caps ,Earth Sciences ,Medicine ,Collagen ,Microscopy, Polarization ,Anatomy ,Collagens ,Azo Compounds ,Biomedical engineering ,Research Article - Abstract
Collagen is an important component in maintaining structural integrity and functionality of tissues and is modulated in various biological processes. Its visualization and possible quantification using histopathological stains can be important for understanding disease progression or therapeutic response. Visualization of collagen fiber with the histological stain picrosirius red (PSR) is enhanced with polarized light and quantitative analysis is possible using circular polarizers. However, linear polarizers are more commonly available and easier to optically align. The objective of the present study is to demonstrate a novel image acquisition technique and analysis method using linearly polarized light. The proposed imaging technique is based on image acquisition at multiple slide rotation angles, which are co-registered to form a composite image used for quantitative analysis by pixel intensity or pixel counting. The technique was demonstrated on multiple human coronary samples with varying histopathologies and developed specifically to analyze cap collagen in atherosclerotic plaque. Pixel counting image analysis was found to be reproducible across serial tissue sections and across different users and sufficiently sensitive to detect differences in cap structural integrity that are likely relevant to prediction of rupture risk. The benefit of slide rotation angle under linear polarization to acquire images represents a feasible and practical implementation for expanding the general utility of PSR for quantitative analysis.
- Published
- 2021
29. The use of 33 MHz ultra-high-frequency ultrasonography for the evaluation of sweat glands in the axilla with osmidrosis
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Akira Shinaoka, Masanori Saeki, and Ryuichi Nakahara
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Male ,Physiology ,H&E stain ,Biochemistry ,Diagnostic Radiology ,SWEAT ,Fats ,Subcutaneous Tissue ,Ultrasound Imaging ,Sweat Gland Diseases ,Medicine and Health Sciences ,Sweat ,Ultrasonography ,Skin ,Aged, 80 and over ,Multidisciplinary ,integumentary system ,Radiology and Imaging ,Apocrine ,Anatomy ,Dermis ,Middle Aged ,Lipids ,Body Fluids ,medicine.anatomical_structure ,Medicine ,Female ,Integumentary System ,Subcutaneous tissue ,Research Article ,Histology ,Imaging Techniques ,Science ,Research and Analysis Methods ,Composite Images ,Exocrine Glands ,Diagnostic Medicine ,Sweat gland ,medicine ,Humans ,Aged ,business.industry ,Biology and Life Sciences ,Sweat Glands ,Axilla ,Biological Tissue ,business - Abstract
Background This study aimed to assess the use of 33 MHz ultra-high-frequency ultrasonography (33MHz-UHFUS) for evaluating axillary sweat glands with osmidrosis in comparison with histological techniques. Axillary osmidrosis is a common problem in Asian societies, and the number and size of apocrine sweat glands have a strong relationship with osmidrosis severity. Currently, there are no methods to evaluate sweat gland distribution non-invasively. Methods In this study, 35 skin specimens from 10 fresh human cadavers without osmidrosis and retrospective ultrasonographic images from 20 patients with osmidrosis were used. Skin specimens were embedded in paraffin, thinly sliced, and finally stained with hematoxylin and eosin. Histologically, the apocrine and eccrine glands were evaluated, and the top and bottom depths of follicles were measured from the skin surface. In 33 MHz ultrasonography images, the depths of sweat glands were measured, and the mean grey value was calculated using Image J. Results Compared to histological data, 33MHz-UHFUS could be used to identify sweat glands as a hyperechoic structure between the dermis and fat layer. Furthermore, it could evaluate sweat gland distribution but could not distinguish between types of sweat glands. Conclusions The distribution of sweat glands in the axilla can be non-invasively evaluated via 33MHz-UHFUS.
- Published
- 2021
30. A hybrid level set model for image segmentation
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Anup Basu, Bin Pan, Changjiang Liu, and Weiqin Chen
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Computer and Information Sciences ,Evolutionary Processes ,Computer science ,Imaging Techniques ,Science ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Digital Imaging ,Research and Analysis Methods ,Grayscale ,Pattern Recognition, Automated ,Composite Images ,Digital Computing ,Level set ,Image Interpretation, Computer-Assisted ,Differential Equations ,Image Processing, Computer-Assisted ,Segmentation ,Computer vision ,Computer Simulation ,ComputingMethodologies_COMPUTERGRAPHICS ,Active contour model ,Evolutionary Biology ,Multidisciplinary ,Models, Statistical ,Computing Systems ,business.industry ,Computers ,Applied Mathematics ,Simulation and Modeling ,Digital imaging ,Partial Differential Equations ,Biology and Life Sciences ,Image segmentation ,Maxima and minima ,Computer Science::Computer Vision and Pattern Recognition ,Physical Sciences ,Medicine ,Artificial intelligence ,business ,Smoothing ,Algorithms ,Mathematics ,Research Article - Abstract
Active contour models driven by local binary fitting energy can segment images with inhomogeneous intensity, while being prone to falling into a local minima. However, the segmentation result largely depends on the location of the initial contour. We propose an active contour model with global and local image information. The local information of the model is obtained by bilateral filters, which can also enhance the edge information while smoothing the image. The local fitting centers are calculated before the contour evolution, which can alleviate the iterative process and achieve fast image segmentation. The global information of the model is obtained by simplifying the C-V model, which can assist contour evolution, thereby increasing accuracy. Experimental results show that our algorithm is insensitive to the initial contour position, and has higher precision and speed.
- Published
- 2021
31. Carotenoid Distribution in Living Cells of Haematococcus pluvialis (Chlorophyceae)
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Evens, Terence
- Published
- 2011
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32. Visualizing Late Insect Embryogenesis: Extraembryonic and Mesodermal Enhancer Trap Expression in the Beetle Tribolium castaneum.
- Author
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Koelzer, Stefan, Kölsch, Yvonne, and Panfilio, Kristen A.
- Subjects
- *
INSECT embryology , *RED flour beetle , *INSECT genetics , *GENE expression , *TRANSPOSONS , *GREEN fluorescent protein , *COMPARATIVE studies , *INSECTS - Abstract
The beetle Tribolium castaneum has increasingly become a powerful model for comparative research on insect development. One recent resource is a collection of piggyBac transposon-based enhancer trap lines. Here, we provide a detailed analysis of three selected lines and demonstrate their value for investigations in the second half of embryogenesis, which has thus far lagged behind research on early stages. Two lines, G12424 and KT650, show enhanced green fluorescent protein (EGFP) expression throughout the extraembryonic serosal tissue and in a few discrete embryonic domains. Intriguingly, both lines show for the first time a degree of regionalization within the mature serosa. However, their expression profiles illuminate distinct aspects of serosal biology: G12424 tracks the tissue’s rapid maturation while KT650 expression likely reflects ongoing physiological processes. The third line, G04609, is stably expressed in mesodermal domains, including segmental muscles and the heart. Genomic mapping followed by in situ hybridization for genes near to the G04609 insertion site suggests that the transposon has trapped enhancer information for the Tribolium orthologue of midline (Tc-mid). Altogether, our analyses provide the first live imaging, long-term characterizations of enhancer traps from this collection. We show that EGFP expression is readily detected, including in heterozygote crosses that permit the simultaneous visualization of multiple tissue types. The tissue specificity provides live, endogenous marker gene expression at key developmental stages that are inaccessible for whole mount staining. Furthermore, the nonlocalized EGFP in these lines illuminates both the nucleus and cytoplasm, providing cellular resolution for morphogenesis research on processes such as dorsal closure and heart formation. In future work, identification of regulatory regions driving these enhancer traps will deepen our understanding of late developmental control, including in the extraembryonic domain, which is a hallmark of insect development but which is not yet well understood. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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33. Visualizing Late Insect Embryogenesis: Extraembryonic and Mesodermal Enhancer Trap Expression in the Beetle Tribolium castaneum.
- Author
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Koelzer, Stefan, Kölsch, Yvonne, and Panfilio, Kristen A.
- Subjects
INSECT embryology ,RED flour beetle ,INSECT genetics ,GENE expression ,TRANSPOSONS ,GREEN fluorescent protein ,COMPARATIVE studies ,INSECTS - Abstract
The beetle Tribolium castaneum has increasingly become a powerful model for comparative research on insect development. One recent resource is a collection of piggyBac transposon-based enhancer trap lines. Here, we provide a detailed analysis of three selected lines and demonstrate their value for investigations in the second half of embryogenesis, which has thus far lagged behind research on early stages. Two lines, G12424 and KT650, show enhanced green fluorescent protein (EGFP) expression throughout the extraembryonic serosal tissue and in a few discrete embryonic domains. Intriguingly, both lines show for the first time a degree of regionalization within the mature serosa. However, their expression profiles illuminate distinct aspects of serosal biology: G12424 tracks the tissue’s rapid maturation while KT650 expression likely reflects ongoing physiological processes. The third line, G04609, is stably expressed in mesodermal domains, including segmental muscles and the heart. Genomic mapping followed by in situ hybridization for genes near to the G04609 insertion site suggests that the transposon has trapped enhancer information for the Tribolium orthologue of midline (Tc-mid). Altogether, our analyses provide the first live imaging, long-term characterizations of enhancer traps from this collection. We show that EGFP expression is readily detected, including in heterozygote crosses that permit the simultaneous visualization of multiple tissue types. The tissue specificity provides live, endogenous marker gene expression at key developmental stages that are inaccessible for whole mount staining. Furthermore, the nonlocalized EGFP in these lines illuminates both the nucleus and cytoplasm, providing cellular resolution for morphogenesis research on processes such as dorsal closure and heart formation. In future work, identification of regulatory regions driving these enhancer traps will deepen our understanding of late developmental control, including in the extraembryonic domain, which is a hallmark of insect development but which is not yet well understood. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
34. The length of a scroll: Quantitative evaluation of material reconstructions
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Nachum Dershowitz and Eshbal Ratzon
- Subjects
Computer and Information Sciences ,Computer science ,Imaging Techniques ,Science ,Scroll ,Geometry ,Social Sciences ,Distance Measurement ,Digital Imaging ,Research and Analysis Methods ,Composite Images ,Empirical validity ,Mathematical and Statistical Techniques ,Animal Products ,Statistics ,Measurement ,Multidisciplinary ,Approximation Methods ,Mathematical Models ,Biology and Life Sciences ,Agriculture ,Leather ,Radii ,Archaeology ,Physical Sciences ,Medicine ,Engineering and Technology ,Mathematics ,Research Article - Abstract
Scholars have used mathematical models to estimate the missing length of deteriorated scrolls from ancient Egypt, Qumran, Herculaneum, and elsewhere. Based on such estimations, the content of ancient literature as well as the process of its composition is deduced. Though theoretically reasonable, many practical problems interfere with the method. In the current study, the empirical validity of these mathematical models is examined, showing that highly significant errors are quite frequent. When applied to comparatively intact scrolls, the largest contribution to errors is the subjectivity inherent in measuring patterns of damaged areas. In less well preserved scrolls, deterioration and deformation are more central causes of errors. Another factor is the quality of imaging. Hence, even after maximal reduction of interfering factors, one should only use these estimation methods in conjunction with other supporting considerations. Accordingly, past uses of this approach should be reevaluated, which may have substantial implications for the study of antiquity.
- Published
- 2020
35. Automated measurement of anteroposterior diameter and foraminal widths in MRI images for lumbar spinal stenosis diagnosis
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Julio Christian Young, Ala S. Al-Kafri, Nunik Afriliana, Sud Sudirman, Mohammed Al-Jumaily, Reyhan Eddy Yunus, Friska Natalia, and Hira Meidia
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Male ,Intervertebral Disc Degeneration ,02 engineering and technology ,Nervous System ,Diagnostic Radiology ,Mri image ,Spinal Stenosis ,0302 clinical medicine ,Medicine and Health Sciences ,0202 electrical engineering, electronic engineering, information engineering ,Segmentation ,Musculoskeletal System ,Mathematics ,Stenosis ,Multidisciplinary ,medicine.diagnostic_test ,Nerves ,Radiology and Imaging ,Applied Mathematics ,Simulation and Modeling ,Lumbar spinal stenosis ,Magnetic Resonance Imaging ,Low back pain ,medicine.anatomical_structure ,Physical Sciences ,Medicine ,Female ,020201 artificial intelligence & image processing ,Thecal sac ,Anatomy ,medicine.symptom ,Intervertebral Disc Displacement ,Algorithms ,Research Article ,QA75 ,Imaging Techniques ,Science ,Lower Back Pain ,Pain ,Research and Analysis Methods ,QA76 ,Composite Images ,03 medical and health sciences ,Signs and Symptoms ,Diagnostic Medicine ,medicine ,Humans ,Skeleton ,business.industry ,Lumbosacral Region ,Biology and Life Sciences ,Intervertebral disc ,Magnetic resonance imaging ,medicine.disease ,R1 ,Spine ,Spinal Nerves ,Clinical Medicine ,Nuclear medicine ,business ,Low Back Pain ,Spinal Canal ,030217 neurology & neurosurgery - Abstract
Lumbar Spinal Stenosis causes low back pain through pressures exerted on the spinal nerves. This can be verified by measuring the anteroposterior diameter and foraminal widths of the patient’s lumbar spine. Our goal is to develop a novel strategy for assessing the extent of Lumbar Spinal Stenosis by automatically calculating these distances from the patient’s lumbar spine MRI. Our method starts with a semantic segmentation of T1- and T2-weighted composite axial MRI images using SegNet that partitions the image into six regions of interest. They consist of three main regions-of-interest, namely the Intervertebral Disc, Posterior Element, and Thecal Sac, and three auxiliary regions-of-interest that includes the Area between Anterior and Posterior elements. A novel contour evolution algorithm is then applied to improve the accuracy of the segmentation results along important region boundaries. Nine anatomical landmarks on the image are located by delineating the region boundaries found in the segmented image before the anteroposterior diameter and foraminal widths can be measured. The performance of the proposed algorithm was evaluated through a set of experiments on the Lumbar Spine MRI dataset containing MRI studies of 515 patients. These experiments compare the performance of our contour evolution algorithm with the Geodesic Active Contour and Chan-Vese methods over 22 different setups. We found that our method works best when our contour evolution algorithm is applied to improve the accuracy of both the label images used to train the SegNet model and the automatically segmented image. The average error of the calculated right and left foraminal distances relative to their expert-measured distances are 0.28 mm (p = 0.92) and 0.29 mm (p = 0.97), respectively. The average error of the calculated anteroposterior diameter relative to their expert-measured diameter is 0.90 mm (p = 0.92). The method also achieves 96.7% agreement with an expert opinion on determining the severity of the Intervertebral Disc herniations.
- Published
- 2020
36. Deep learning of cuneiform sign detection with weak supervision using transliteration alignment
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Pablo Klinkisch, Tobias Dencker, Björn Ommer, and Stefan M. Maul
- Subjects
Computer science ,Computer Vision ,Social Sciences ,02 engineering and technology ,computer.software_genre ,Computer Applications ,Machine Learning ,Database and Informatics Methods ,Cognition ,Reading (process) ,0202 electrical engineering, electronic engineering, information engineering ,Transliteration ,Image Processing, Computer-Assisted ,Psychology ,History, Ancient ,media_common ,Language ,Multidisciplinary ,Process (computing) ,Web-Based Applications ,Medicine ,020201 artificial intelligence & image processing ,Sequence Analysis ,Natural language processing ,Research Article ,Computer and Information Sciences ,Bioinformatics ,Imaging Techniques ,media_common.quotation_subject ,Science ,Decision Making ,Research and Analysis Methods ,Composite Images ,Middle East ,Deep Learning ,Artificial Intelligence ,Humans ,business.industry ,Deep learning ,Cognitive Psychology ,Latin script ,Biology and Life Sciences ,020206 networking & telecommunications ,Reading ,Cognitive Science ,Artificial intelligence ,Neural Networks, Computer ,business ,computer ,Sequence Alignment ,Sign (mathematics) ,Neuroscience - Abstract
The cuneiform script provides a glimpse into our ancient history. However, reading age-old clay tablets is time-consuming and requires years of training. To simplify this process, we propose a deep-learning based sign detector that locates and classifies cuneiform signs in images of clay tablets. Deep learning requires large amounts of training data in the form of bounding boxes around cuneiform signs, which are not readily available and costly to obtain in the case of cuneiform script. To tackle this problem, we make use of existing transliterations, a sign-by-sign representation of the tablet content in Latin script. Since these do not provide sign localization, we propose a weakly supervised approach: We align tablet images with their corresponding transliterations to localize the transliterated signs in the tablet image, before using these localized signs in place of annotations to re-train the sign detector. A better sign detector in turn boosts the quality of the alignments. We combine these steps in an iterative process that enables training a cuneiform sign detector from transliterations only. While our method works weakly supervised, a small number of annotations further boost the performance of the cuneiform sign detector which we evaluate on a large collection of clay tablets from the Neo-Assyrian period. To enable experts to directly apply the sign detector in their study of cuneiform texts, we additionally provide a web application for the analysis of clay tablets with a trained cuneiform sign detector.
- Published
- 2020
37. Post-processing central k-space subtraction for high-resolution arterial peripheral MR angiography
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Gedat, Egbert, Mohajer, Mojgan, Kirsch, Rainer, and Frericks, Bernd
- Subjects
- *
ANGIOGRAPHY , *MAGNETIC resonance imaging , *MEDICAL radiography , *RADIOSCOPIC diagnosis , *BLOOD vessels , *COMPUTERS in medicine - Abstract
Abstract: Peripheral MR angiography requires high resolution and arterial contrast. Neither can be obtained simultaneously due to the short arterial phase of the contrast agent. To improve temporal resolution, keyhole imaging was developed, which combines high resolution and arterial k-spaces at the time of image acquisition. Here, a related approach is introduced for image post-processing in the Fourier domain. It is demonstrated that simple substitution of the central k-space with low-resolution data leads to severe distortion. Hence, a dedicated calculation scheme is necessary for composite k-space post-processing. A solution is presented for high-resolution arterial peripheral MR angiography that uses subtraction of venous intensities from the central high-resolution k-space. The calculations in the Fourier domain do not require interpolations between the different resolutions. High-resolution steady-state MR angiography, which exhibits contrast-enhanced arteries and veins at an isotropic resolution of 0.65 mm, and standard resolution arterial first-pass MR angiography were combined to obtain images with the resolution of the steady-state images and arterial contrast. Numerical simulations on software phantoms are presented. The operation of the method is demonstrated in five patients. [Copyright &y& Elsevier]
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- 2011
- Full Text
- View/download PDF
38. A fully-automated, robust, and versatile algorithm for long-term budding yeast segmentation and tracking
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N. Ezgi Wood and Andreas Doncic
- Subjects
Fluorescence-lifetime imaging microscopy ,Computer science ,Yeast and Fungal Models ,Tracking (particle physics) ,Cell morphology ,Bright Field Microscopy ,Automation ,0302 clinical medicine ,Image Processing, Computer-Assisted ,Morphogenesis ,Segmentation ,Electron Microscopy ,0303 health sciences ,Microscopy ,Multidisciplinary ,Applied Mathematics ,Simulation and Modeling ,Eukaryota ,Light Microscopy ,Fully automated ,Experimental Organism Systems ,Cell Tracking ,Physical Sciences ,Saccharomyces Cerevisiae ,Medicine ,Algorithm ,Algorithms ,Cell Division ,Research Article ,Imaging Techniques ,Science ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Image processing ,Research and Analysis Methods ,Composite Images ,03 medical and health sciences ,Saccharomyces ,Model Organisms ,Fluorescence Imaging ,030304 developmental biology ,Cell Proliferation ,Organisms ,Fungi ,Biology and Life Sciences ,Morphogenic Segmentation ,Budding yeast ,Yeast ,Term (time) ,Microscopy, Fluorescence ,Bright Field Imaging ,Saccharomycetales ,Animal Studies ,Transmission Electron Microscopy ,030217 neurology & neurosurgery ,Mathematics ,Developmental Biology - Abstract
Live cell time-lapse microscopy, a widely-used technique to study gene expression and protein dynamics in single cells, relies on segmentation and tracking of individual cells for data generation. The potential of the data that can be extracted from this technique is limited by the inability to accurately segment a large number of cells from such microscopy images and track them over long periods of time. Existing segmentation and tracking algorithms either require additional dyes or markers specific to segmentation or they are highly specific to one imaging condition and cell morphology and/or necessitate manual correction. Here we introduce a fully automated, fast and robust segmentation and tracking algorithm for budding yeast that overcomes these limitations. Full automatization is achieved through a novel automated seeding method, which first generates coarse seeds, then automatically fine-tunes cell boundaries using these seeds and automatically corrects segmentation mistakes. Our algorithm can accurately segment and track individual yeast cells without any specific dye or biomarker. Moreover, we show how existing channels devoted to a biological process of interest can be used to improve the segmentation. The algorithm is versatile in that it accurately segments not only cycling cells with smooth elliptical shapes, but also cells with arbitrary morphologies (e.g. sporulating and pheromone treated cells). In addition, the algorithm is largely independent of the specific imaging method (bright-field/phase) and objective used (40X/63X). We validate our algorithm’s performance on 9 cases each entailing a different imaging condition, objective magnification and/or cell morphology. Taken together, our algorithm presents a powerful segmentation and tracking tool that can be adapted to numerous budding yeast single-cell studies.
- Published
- 2019
39. Frequency division denoising algorithm based on VIF adaptive 2D-VMD ultrasound image
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Yang Xu, Hongbo Yan, Pengbo Zhao, Zhuang Du, and Pei Liu
- Subjects
Statistical Noise ,Computer science ,02 engineering and technology ,Signal-To-Noise Ratio ,Diagnostic Radiology ,Ultrasound Imaging ,Image Processing, Computer-Assisted ,Medicine and Health Sciences ,0202 electrical engineering, electronic engineering, information engineering ,Computer vision ,Ultrasonography ,Multidisciplinary ,Radiology and Imaging ,Applied Mathematics ,Simulation and Modeling ,Physics ,Statistics ,Condensed Matter Physics ,Gaussian Noise ,Physical Sciences ,Ultrasound imaging ,symbols ,Medicine ,Engineering and Technology ,020201 artificial intelligence & image processing ,Artifacts ,Algorithms ,Research Article ,Imaging Techniques ,Science ,Noise reduction ,Materials Science ,Material Properties ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Research and Analysis Methods ,Image (mathematics) ,Composite Images ,symbols.namesake ,Diagnostic Medicine ,Humans ,Computer Simulation ,Block-matching algorithm ,business.industry ,020206 networking & telecommunications ,Speckle noise ,Real image ,Noise Reduction ,Noise ,Gaussian noise ,Computer Science::Computer Vision and Pattern Recognition ,Signal Processing ,Imaging technology ,Anisotropy ,Artificial intelligence ,Tomography, X-Ray Computed ,business ,Mathematics - Abstract
Ultrasound imaging has developed into an indispensable imaging technology in medical diagnosis and treatment applications due to its unique advantages, such as safety, affordability, and convenience. With the development of data information acquisition technology, ultrasound imaging is increasingly susceptible to speckle noise, which leads to defects, such as low resolution, poor contrast, spots, and shadows, which affect the accuracy of physician analysis and diagnosis. To solve this problem, we proposed a frequency division denoising algorithm combining transform domain and spatial domain. First, the ultrasound image was decomposed into a series of sub-modal images using 2D variational mode decomposition (2D-VMD), and adaptively determined 2D-VMD parameter K value based on visual information fidelity (VIF) criterion. Then, an anisotropic diffusion filter was used to denoise low-frequency sub-modal images, and a 3D block matching algorithm (BM3D) was used to reduce noise for high-frequency images with high noise. Finally, each sub-modal image was reconstructed after processing to obtain the denoised ultrasound image. In the comparative experiments of synthetic, simulation, and real images, the performance of this method was quantitatively evaluated. Various results show that the ability of this algorithm in denoising and maintaining structural details is significantly better than that of other algorithms.
- Published
- 2021
40. FOSTER—An R package for forest structure extrapolation
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Martin Queinnec, Douglas K. Bolton, Piotr Tompalski, and Nicholas C. Coops
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010504 meteorology & atmospheric sciences ,Computer science ,Extrapolation ,0211 other engineering and technologies ,02 engineering and technology ,Forests ,Overfitting ,computer.software_genre ,01 natural sciences ,Trees ,Remote Sensing ,Machine Learning ,Geoinformatics ,Imputation (statistics) ,Lidar ,Numerical Analysis ,Multidisciplinary ,Ecology ,Geography ,Eukaryota ,Software Engineering ,Sampling (statistics) ,Plants ,Terrestrial Environments ,Spatial Autocorrelation ,Photogrammetry ,Physical Sciences ,Medicine ,Engineering and Technology ,Data mining ,Research Article ,Computer and Information Sciences ,Imaging Techniques ,Science ,Forest management ,Sample (statistics) ,Research and Analysis Methods ,Ecosystems ,Composite Images ,Artificial Intelligence ,Preprocessing ,Spatial analysis ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Ecology and Environmental Sciences ,Organisms ,Biology and Life Sciences ,Remote Sensing Technology ,Earth Sciences ,computer ,Software ,Mathematics - Abstract
The uptake of technologies such as airborne laser scanning (ALS) and more recently digital aerial photogrammetry (DAP) enable the characterization of 3-dimensional (3D) forest structure. These forest structural attributes are widely applied in the development of modern enhanced forest inventories. As an alternative to extensive ALS or DAP based forest inventories, regional forest attribute maps can be built from relationships between ALS or DAP and wall-to-wall satellite data products. To date, a number of different approaches exist, with varying code implementations using different programming environments and tailored to specific needs. With the motivation for open, simple and modern software, we presentFOSTER(Forest Structure Extrapolation in R), a versatile and computationally efficient framework for modeling and imputation of 3D forest attributes.FOSTERderives spectral trends in remote sensing time series, implements a structurally guided sampling approach to sample these often spatially auto correlated datasets, to then allow a modelling approach (currently k-NN imputation) to extrapolate these 3D forest structure measures. The k-NN imputation approach thatFOSTERimplements has a number of benefits over conventional regression based approaches including lower bias and reduced over fitting. This paper provides an overview of the general framework followed by a demonstration of the performance and outputs ofFOSTER. Two ALS-derived variables, the 95thpercentile of first returns height (elev_p95) and canopy cover above mean height (cover), were imputed over a research forest in British Columbia, Canada with relative RMSE of 18.5% and 11.4% and relative bias of -0.6% and 1.4% respectively. The processing sequence developed withinFOSTERrepresents an innovative and versatile framework that should be useful to researchers and managers alike looking to make forest management decisions over entire forest estates.
- Published
- 2021
41. Assessment of forest cover and carbon stock changes in sub-tropical pine forest of Azad Jammu & Kashmir (AJK), Pakistan using multi-temporal Landsat satellite data and field inventory
- Author
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Nasir Hameed, Junaid Aziz Khan, Muhammad Hasan Ali Baig, Mobushir Riaz Khan, Zaker Hussain, and Iftikhar Ahmad Khan
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,Sustainable forest management ,0211 other engineering and technologies ,Plant Science ,02 engineering and technology ,Forests ,Carbon sequestration ,01 natural sciences ,Trees ,Pakistan ,Carbon stock ,Multidisciplinary ,Ecology ,Plant Anatomy ,Eukaryota ,Reforestation ,Plants ,Terrestrial Environments ,Wood ,Chemistry ,Physical Sciences ,Medicine ,Engineering and Technology ,Temperate Forests ,Temperate rainforest ,Research Article ,Environmental Monitoring ,Carbon Sequestration ,Conservation of Natural Resources ,Environmental Engineering ,Imaging Techniques ,Science ,Subtropics ,Research and Analysis Methods ,Ecosystems ,Composite Images ,Greenhouse Gases ,Environmental Chemistry ,Ecosystem ,Stock (geology) ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Ecology and Environmental Sciences ,Organisms ,Chemical Compounds ,Biology and Life Sciences ,Forestry ,Carbon Dioxide ,Pinus ,Carbon ,Atmospheric Chemistry ,Remote Sensing Technology ,Earth Sciences ,Environmental science ,Pines - Abstract
This study aimed at estimating temporal (1989-2018) change in forest cover, carbon stock and trend in corresponding CO2 emissions/sequestration of a sub-tropical pine forest (STPF) in AJK, Pakistan. Our field inventory estimation shows an average above ground biomass (AAGB) accumulation of 0.145 Kt/ha with average carbon stock (ACS) value of 0.072 Kt/ha. Landsat TM, ETM+ and OLI images of 1989, 1993, 1999, 2005, 2010, 2015 and 2018 were used to extract vegetation fractions through Linear Spectral Mixture Analysis (LSMA) and forest area was calculated for respective years. Based on the forest area and estimated ACS value, the biomass carbon stock with corresponding CO2 emissions/sequestration was worked out for each time and change in forest carbon stock was determined for different time periods from 1989 to 2018. Our analysis shows net increase of 561 ha in forest cover and 40.39 Kt of ACS along with increase in corresponding CO2 sequestrations of 147.83 Kt over the study period. The results based on combination of remote sensing and field inventory provide valuable information and scientific basis to plan and ensure sustainable forest management (SFM) through reforestation, protection and conservation to enhance and maintain adequate forest cover and reduce CO2 emissions.
- Published
- 2020
42. Grid stage modelling functions and molecular vector graphics.
- Author
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Dubois, J., Yue, S., and Doucet, J.
- Abstract
A polymodelling system (POLYMOD) is presented for varied 2D or 3D displays of chemical shapes, whether structural (molecular volumes distances, surfaces...) or electronic (molecular electrostatic potential, electron densities ...). The POLYMOD system manages reversible correspondences between calculation and representation spaces by immersing the molecules studied in a unique represetation space structured by a 3D grid box. This box, called COOBOX, defined by its point internal coordinates, is used to transform other coordinates into its own. Direct multi-slice images along the x, y, z axis provide access to a variety of derived operations around a molecular shape or set of shapes disposed in various manners. Interactive sub systems ensure Boolean operations and compare property shapes through the 3D grid. Clear separation of graphic routine and of downstream modelling programs leads to rapid and original generation of varied images (subimages, direct or composite images) which are then available for simulation strategies. [ABSTRACT FROM AUTHOR]
- Published
- 1986
- Full Text
- View/download PDF
43. Negative body image
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Klaske A. Glashouwer, Paula von Spreckelsen, Elise C. Bennik, Peter J. de Jong, Ineke Wessel, and Clinical Psychology and Experimental Psychopathology
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Male ,050103 clinical psychology ,SYMPTOMS ,Eating Disorders ,Emotions ,Social Sciences ,lcsh:Medicine ,Mathematical and Statistical Techniques ,0302 clinical medicine ,NONCLINICAL POPULATION ,Surveys and Questionnaires ,Medicine and Health Sciences ,Psychology ,lcsh:Science ,SCALE ,media_common ,DISSATISFACTION ,Multidisciplinary ,05 social sciences ,humanities ,Eating disorders ,Feeling ,Physical Sciences ,Trait ,Regression Analysis ,SYMPTOMATOLOGY ,Female ,Statistics (Mathematics) ,Research Article ,Clinical psychology ,Adult ,Mediation (statistics) ,DOMAINS ,Imaging Techniques ,media_common.quotation_subject ,Self-concept ,Dermatology ,Research and Analysis Methods ,Composite Images ,Young Adult ,03 medical and health sciences ,Mental Health and Psychiatry ,Negative body image ,Body Image ,medicine ,Humans ,0501 psychology and cognitive sciences ,Statistical Methods ,Association (psychology) ,Behavior ,lcsh:R ,Biology and Life Sciences ,EATING-DISORDERS ,medicine.disease ,Self Concept ,Disgust ,030227 psychiatry ,Acne ,lcsh:Q ,WEIGHT ,Mathematics - Abstract
Consistent with the view that disgust might be involved in persistent body dissatisfaction, there is preliminary evidence showing a positive correlation between measures of negative body image and indices of both trait disgust and self-directed disgust. In two correlational studies among undergraduates (N = 577 and N = 346, respectively) we aimed at replicating and extending these findings by testing a series of critical relationships, which follow from our hypotheses that 1) trait disgust propensity would increase the risk of developing a negative body image by increasing the likelihood of feeling self-disgust, and 2) trait disgust sensitivity would heighten the impact of self-disgust on the development of persistent negative body appraisals. Replicating previous research, both studies showed that negative body image was positively related to self-disgust, disgust propensity and disgust sensitivity. Mediation analyses showed that, in line with our model, self-disgust partly accounted for the association between disgust propensity and negative body image. Although disgust sensitivity showed an independent relationship with body image, disgust sensitivity did not moderate the association between self-disgust and negative body image. All in all, findings are consistent with the view that self-disgust-induced avoidance may contribute to persistent negative body appraisals.
- Published
- 2018
44. Progressive derivation of serially homologous neuroblast lineages in the gnathal CNS of Drosophila
- Author
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Olaf Vef, Gerhard M. Technau, Karin Lüer, and Christof Rickert
- Subjects
0301 basic medicine ,Central Nervous System ,Embryology ,lcsh:Medicine ,Serial homology ,Gene Expression ,Nervous System ,Animal Cells ,Medicine and Health Sciences ,Brainbow Labeling ,lcsh:Science ,Neurons ,Brain Mapping ,Multidisciplinary ,biology ,Anatomy ,Neuromere ,Neural stem cell ,Chemistry ,Physical Sciences ,Drosophila ,Drosophila melanogaster ,Cellular Types ,Homeotic gene ,Research Article ,Lineage (genetic) ,Imaging Techniques ,Neuroimaging ,Research and Analysis Methods ,Composite Images ,03 medical and health sciences ,Neuroblast ,Interneurons ,Genetics ,Animals ,Cell Lineage ,Molecular Biology Techniques ,Molecular Biology ,Ground State ,lcsh:R ,Embryos ,Biology and Life Sciences ,Cell Biology ,Quantum Chemistry ,biology.organism_classification ,030104 developmental biology ,Ventral nerve cord ,Cellular Neuroscience ,lcsh:Q ,Cloning ,Neuroscience ,Developmental Biology - Abstract
Along the anterior-posterior axis the central nervous system is subdivided into segmental units (neuromeres) the composition of which is adapted to their region-specific functional requirements. In Drosophila melanogaster each neuromere is formed by a specific set of identified neural stem cells (neuroblasts, NBs). In the thoracic and anterior abdominal region of the embryonic ventral nerve cord segmental sets of NBs resemble the ground state (2nd thoracic segment, which does not require input of homeotic genes), and serial (segmental) homologs generate similar types of lineages. The three gnathal head segments form a transitional zone between the brain and the ventral nerve cord. It has been shown recently that although all NBs of this zone are serial homologs of NBs in more posterior segments, they progressively differ from the ground state in anterior direction (labial > maxillary > mandibular segment) with regard to numbers and expression profiles. To study the consequences of their derived characters we traced the embryonic lineages of gnathal NBs using the Flybow and DiI-labelling techniques. For a number of clonal types serial homology is rather clearly reflected by their morphology (location and projection patterns) and cell specific markers, despite of reproducible segment-specific differences. However, many lineages, particularly in the mandibular segment, show a degree of derivation that impedes their assignment to ground state serial homologs. These findings demonstrate that differences in gene expression profiles of gnathal NBs go along with anteriorly directed progressive derivation in the composition of their lineages. Furthermore, lineage sizes decrease from labial to mandibular segments, which in concert with decreasing NB-numbers lead to reduced volumes of gnathal neuromeres, most significantly in the mandibular segment.
- Published
- 2018
45. Semi-automated digital measurement as the method of choice for beta cell mass analysis
- Author
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Violette Coppens, Gunter Leuckx, Yves Heremans, Willem Staels, Luc Baeyens, Harry Heimberg, Yannick Verdonck, Nico De Leu, Beta Cell Neogenesis, Pathology/molecular and cellular medicine, Faculty of Medicine and Pharmacy, Clinical sciences, and Internal Medicine
- Subjects
0301 basic medicine ,Computer science ,Physiology ,medicine.medical_treatment ,Image Processing ,lcsh:Medicine ,SOFTWARE ,Immunostaining ,Biochemistry ,Automation ,Endocrinology ,Mathematical and Statistical Techniques ,Digital image processing ,Medicine and Health Sciences ,Insulin ,Mass analysis ,lcsh:Science ,Staining ,Multidisciplinary ,Agricultural and Biological Sciences(all) ,medicine.anatomical_structure ,Mouse Pancreas ,Physical Sciences ,Engineering and Technology ,Pancreatic injury ,Beta cell ,Anatomy ,Pancreas ,Engineering sciences. Technology ,Statistics (Mathematics) ,Research Article ,Imaging Techniques ,Image processing ,Endocrine System ,Research and Analysis Methods ,Composite Images ,03 medical and health sciences ,Islets of Langerhans ,Text mining ,Exocrine Glands ,medicine ,Animals ,Statistical Methods ,IMAGE-ANALYSIS ,Beta cell mass ,Diabetic Endocrinology ,Artifact (error) ,Analysis of Variance ,Endocrine Physiology ,Biochemistry, Genetics and Molecular Biology(all) ,business.industry ,Bile duct ligation ,Morphometry ,lcsh:R ,Insulin Signaling ,Biology and Life Sciences ,medicine.disease ,Hormones ,030104 developmental biology ,Specimen Preparation and Treatment ,Signal Processing ,lcsh:Q ,business ,Mathematics ,Biomedical engineering - Abstract
Pancreas injury by partial duct ligation (PDL) activates beta cell differentiation and proliferation in adult mouse pancreas but remains controversial regarding the anticipated increase in beta cell volume. Several reports unable to show beta cell volume augmentation in PDL pancreas used automated digital image analysis software. We hypothesized that fully automatic beta cell morphometry without manual micrograph artifact remediation introduces bias and therefore might be responsible for reported discrepancies and controversy. However, our present results prove that standard digital image processing with automatic thresholding is sufficiently robust albeit less sensitive and less adequate to demonstrate a significant increase in beta cell volume in PDL versus Sham-operated pancreas. We therefore conclude that other confounding factors such as quality of surgery, selection of samples based on relative abundance of the transcription factor Neurogenin 3 (Ngn3) and tissue processing give rise to inter-laboratory inconsistencies in beta cell volume quantification in PDL pancreas.
- Published
- 2018
46. Supervised spatial classification of multispectral LiDAR data in urban areas
- Author
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Andrew T. Hudak, Li-Jun Zhao, Carlos A. Silva, Ping Tang, Carine Klauberg, Midhun Mohan, and Lian-Zhi Huo
- Subjects
Geographic information system ,010504 meteorology & atmospheric sciences ,Multispectral image ,0211 other engineering and technologies ,Geographic Mapping ,lcsh:Medicine ,02 engineering and technology ,01 natural sciences ,Geographical locations ,Remote Sensing ,Image Processing, Computer-Assisted ,lcsh:Science ,Geographic Areas ,Ontario ,Lidar ,Multidisciplinary ,Geography ,Eukaryota ,Plants ,Satellite Communications ,Data Acquisition ,Hyperparameter optimization ,Engineering and Technology ,Algorithms ,Research Article ,Urban Areas ,Canada ,Conservation of Natural Resources ,Computer and Information Sciences ,Imaging Techniques ,Image processing ,Land cover ,Image Analysis ,Research and Analysis Methods ,Normalized Difference Vegetation Index ,Composite Images ,Grasses ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing ,Spatial Analysis ,Models, Statistical ,business.industry ,lcsh:R ,Organisms ,Biology and Life Sciences ,North America ,Geographic Information Systems ,Earth Sciences ,lcsh:Q ,People and places ,business ,Classifier (UML) - Abstract
Multispectral LiDAR (light detection and ranging) data have been initially used for land cover classification. However, there are still high classification uncertainties, especially in urban areas, where objects are often mixed and confounded. This study investigated the efficiency of combining advanced statistical methods and LiDAR metrics derived from multispectral LiDAR data for improving land cover classification accuracy in urban areas. The study area is located in Oshawa, Ontario, Canada, on the Lake Ontario shoreline. Multispectral Optech Titan LiDAR data over the study area were acquired on 3 September 2014 in a single strip of 3 km2. Using the channels at 1,550 nm (C1), 1,064 nm (C2) and 532 nm (C3), LiDAR intensity data, normalized digital surface model (nDSM), pseudo normalized difference vegetation index (PseudoNDVI), morphological profiles (MP), and a novel hierarchical morphological profiles (HMP) were derived and used as features for the classification. A support vector machine classifier with a radial basis function (RBF) kernel was applied in the classification stage, where the optimal parameters for the classifier were selected by a grid search procedure. The combination of intensity, pseudoNDVI, nDSM and HMP resulted in the best land cover classification, with an overall accuracy of 93.28%.
- Published
- 2018
47. Preparation and characterization of Fe3O4@Au-C225 composite targeted nanoparticles for MRI of human glioma
- Author
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Qianling Lu, Zhong Yuejiao, Guozhong Ji, Zhirui Guo, Yaoqi Ge, Li Yuntao, Peng Zhang, Dai Xinyu, Kangzhen Zhang, and Gang Peng
- Subjects
0301 basic medicine ,Composite Particles ,Human glioma ,Composite number ,Cetuximab ,lcsh:Medicine ,Physical Chemistry ,Diagnostic Radiology ,0302 clinical medicine ,Medicine and Health Sciences ,Enzyme-Linked Immunoassays ,Magnetite Nanoparticles ,lcsh:Science ,Neurological Tumors ,Cultured Tumor Cells ,Multidisciplinary ,Chemistry ,Radiology and Imaging ,Physics ,Tail vein ,Glioma ,Magnetic Resonance Imaging ,Oncology ,Neurology ,030220 oncology & carcinogenesis ,Physical Sciences ,Sorption ,Biological Cultures ,Research Article ,Chemical Elements ,Imaging Techniques ,Absorption (skin) ,Research and Analysis Methods ,Composite Images ,03 medical and health sciences ,Targeted nanoparticles ,Diagnostic Medicine ,In vivo ,Cell Line, Tumor ,medicine ,Humans ,Particle Physics ,Immunoassays ,lcsh:R ,Cancers and Neoplasms ,Cell Cultures ,Glioma Cells ,medicine.disease ,In vitro ,030104 developmental biology ,Immunologic Techniques ,lcsh:Q ,Adsorption ,Gold ,Biomedical engineering - Abstract
Objective To study the characterization of Fe3O4@Au-C225 composite targeted MNPs. Methods Fe3O4@Au-C225 was prepared by the absorption method. The immunosorbent assay was used to evaluate its absorption efficiency at C225 Fc. ZETA SIZER3000 laser particle size analyzer, ultraviolet photometer and its characteristics were analyzed by VSM. the targeting effect of Fe3O4@Au-C225 composite targeted MNPs on U251 cells in vitro were detected by 7.0 Tesla Micro-MR; and subcutaneous transplanted human glioma in nude mice were performed the targeting effect in vivo after tail vein injection of Fe3O4@Au-C225 composite targeted MNPs by MRI. Results The self-prepared Fe3O4@Au composite MNPs can adsorb C225 with high efficiency of adsorption so that Fe3O4@Au-C225 composite targeted MNPs were prepared successfully. Fe3O4@Au-C225 composite targeted MNPs favorably targeted human glioma cell line U251 in vitro; Fe3O4@Au-C225 composite targeted MNPs have good targeting ability to xenografted glioma on nude mice in vivo, and can be traced by MRI. Conclusion The Fe3O4@Au-C225 composite targeted MNPs have the potential to be used as a tracer for glioma in vivo.
- Published
- 2018
48. Effect of intra-articular administration of superparamagnetic iron oxide nanoparticles (SPIONs) for MRI assessment of the cartilage barrier in a large animal model
- Author
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Carola Riccarda Daniel, Raphael Labens, Tobias Schwarz, Xin-Rui Xia, and SA Hall
- Subjects
0301 basic medicine ,Cartilage, Articular ,Male ,Neutrophils ,Swine ,lcsh:Medicine ,Matrix (biology) ,Biochemistry ,Diagnostic Radiology ,Extracellular matrix ,White Blood Cells ,0302 clinical medicine ,Animal Cells ,Medicine and Health Sciences ,Nanotechnology ,lcsh:Science ,Magnetite Nanoparticles ,Barrier function ,Staining ,Multidisciplinary ,Microscopy, Confocal ,medicine.diagnostic_test ,Chemistry ,Drug Administration Routes ,Radiology and Imaging ,Cell Staining ,Magnetic Resonance Imaging ,Chemotaxis, Leukocyte ,medicine.anatomical_structure ,Connective Tissue ,Models, Animal ,Engineering and Technology ,Female ,Anatomy ,Cellular Types ,Research Article ,Imaging Techniques ,MRI contrast agent ,Immune Cells ,Immunology ,Context (language use) ,Research and Analysis Methods ,Composite Images ,03 medical and health sciences ,Diagnostic Medicine ,Journal Article ,medicine ,Animals ,Horses ,Fluorescent Dyes ,030203 arthritis & rheumatology ,Blood Cells ,Cartilage ,lcsh:R ,Bright-field microscopy ,Biology and Life Sciences ,Proteins ,Magnetic resonance imaging ,Cell Biology ,Coculture Techniques ,030104 developmental biology ,Biological Tissue ,Specimen Preparation and Treatment ,Nanoparticles ,lcsh:Q ,Joints ,Collagens ,Biomarkers ,Biomedical engineering ,Articular Cartilage - Abstract
Early diagnosis of cartilage disease at a time when changes are limited to depletion of extracellular matrix components represents an important diagnostic target to reduce patient morbidity. This report is to present proof of concept for nanoparticle dependent cartilage barrier imaging in a large animal model including the use of clinical magnetic resonance imaging (MRI). Conditioned (following matrix depletion) and unconditioned porcine metacarpophalangeal cartilage was evaluated on the basis of fluorophore conjugated 30 nm and 80 nm spherical gold nanoparticle permeation and multiphoton laser scanning and bright field microscopy after autometallographic particle enhancement. Consequently, conditioned and unconditioned joints underwent MRI pre- and post-injection with 12 nm superparamagnetic iron oxide nanoparticles (SPIONs) to evaluate particle permeation in the context of matrix depletion and use of a clinical 1.5 Tesla MRI scanner. To gauge the potential pro-inflammatory effect of intra-articular nanoparticle delivery co-cultures of equine synovium and cartilage tissue were exposed to an escalating dose of SPIONs and IL-6, IL-10, IFN-γ and PGE2 were assessed in culture media. The chemotactic potential of growth media samples was subsequently assessed in transwell migration assays on isolated equine neutrophils. Results demonstrate an increase in MRI signal following conditioning of porcine joints which suggests that nanoparticle dependent compositional cartilage imaging is feasible. Tissue culture and neutrophil migration assays highlight a dose dependent inflammatory response following SPION exposure which at the imaging dose investigated was not different from controls. The preliminary safety and imaging data support the continued investigation of nanoparticle dependent compositional cartilage imaging. To our knowledge, this is the first report in using SPIONs as intra-articular MRI contrast agent for studying cartilage barrier function, which could potentially lead to a new diagnostic technique for early detection of cartilage disease.
- Published
- 2017
49. Automated analysis of co-localized protein expression in histologic sections of prostate cancer
- Author
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Hermann B. Frieboes, Thomas A. Tennill, and Mitchell E. Gross
- Subjects
0301 basic medicine ,Oncology ,CD31 ,Male ,Pathology ,Image Processing ,Protein Expression ,lcsh:Medicine ,Protein expression ,Cohort Studies ,Prostate cancer ,Automation ,0302 clinical medicine ,Medicine and Health Sciences ,lcsh:Science ,Multidisciplinary ,Tissue microarray ,Prostate Cancer ,Prostate Diseases ,Middle Aged ,Neoplasm Proteins ,Platelet Endothelial Cell Adhesion Molecule-1 ,030220 oncology & carcinogenesis ,Immunohistochemistry ,Engineering and Technology ,Anatomy ,Research Article ,PCA3 ,medicine.medical_specialty ,Computer and Information Sciences ,Stromal cell ,Histology ,Imaging Techniques ,Urology ,Tissue Array Analysis ,Biology ,Digital Imaging ,Research and Analysis Methods ,Computer Software ,Composite Images ,03 medical and health sciences ,Internal medicine ,medicine ,Gene Expression and Vector Techniques ,Humans ,Molecular Biology Techniques ,Molecular Biology ,Immunohistochemistry Techniques ,Aged ,Molecular Biology Assays and Analysis Techniques ,lcsh:R ,Prostatic Neoplasms ,Cancers and Neoplasms ,Biology and Life Sciences ,medicine.disease ,Histochemistry and Cytochemistry Techniques ,Genitourinary Tract Tumors ,030104 developmental biology ,Ki-67 Antigen ,Signal Processing ,Immunologic Techniques ,lcsh:Q - Abstract
An automated approach based on routinely-processed, whole-slide immunohistochemistry (IHC) was implemented to study co-localized protein expression in tissue samples. Expression of two markers was chosen to represent stromal (CD31) and epithelial (Ki-67) compartments in prostate cancer. IHC was performed on whole-slide sections representing low-, intermediate-, and high-grade disease from 15 patients. The automated workflow was developed using a training set of regions-of-interest in sequential tissue sections. Protein expression was studied on digital representations of IHC images across entire slides representing formalin-fixed paraffin embedded blocks. Using the training-set, the known association between Ki-67 and Gleason grade was confirmed. CD31 expression was more heterogeneous across samples and remained invariant with grade in this cohort. Interestingly, the Ki-67/CD31 ratio was significantly increased in high (Gleason ≥ 8) versus low/intermediate (Gleason ≤7) samples when assessed in the training-set and the whole-tissue block images. Further, the feasibility of the automated approach to process Tissue Microarray (TMA) samples in high throughput was evaluated. This work establishes an initial framework for automated analysis of co-localized protein expression and distribution in high-resolution digital microscopy images based on standard IHC techniques. Applied to a larger sample population, the approach may help to elucidate the biologic basis for the Gleason grade, which is the strongest, single factor distinguishing clinically aggressive from indolent prostate cancer.
- Published
- 2017
50. Influence of main forcing affecting the Tagus turbid plume under high river discharges using MODIS imagery
- Author
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M. deCastro, Moncho Gómez-Gesteira, Renato Mendes, D. Fernández-Nóvoa, João Miguel Dias, and Nuno Vaz
- Subjects
0106 biological sciences ,Satellite Imagery ,010504 meteorology & atmospheric sciences ,Marine and Aquatic Sciences ,lcsh:Medicine ,Fresh Water ,Forcing (mathematics) ,Wind ,Tides ,01 natural sciences ,Turbidity ,Materials Physics ,Oceans ,lcsh:Science ,Multidisciplinary ,geography.geographical_feature_category ,Physics ,Westerlies ,Plume ,Droughts ,Oceanography ,Geophysics ,Physical Sciences ,Moderate-resolution imaging spectroradiometer ,Estuaries ,Geology ,Research Article ,Freshwater Environments ,Environmental Monitoring ,Imaging Techniques ,Materials Science ,Research and Analysis Methods ,Composite Images ,Rivers ,Downwelling ,Surface Water ,14. Life underwater ,0105 earth and related environmental sciences ,geography ,Discharge ,010604 marine biology & hydrobiology ,Ecology and Environmental Sciences ,lcsh:R ,Aquatic Environments ,Estuary ,Bodies of Water ,Floods ,13. Climate action ,Spain ,Earth Sciences ,Upwelling ,lcsh:Q ,Hydrology - Abstract
The role of river discharge, wind and tide on the extension and variability of the Tagus River plume was analyzed from 2003 to 2015. This study was performed combining daily images obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor located onboard the Aqua and Terra satellites. Composites were generated by averaging pixels with the same forcing conditions. River discharge shows a strong relation with the extension of the Tagus plume. The plume grows with the increasing river discharge and express a two day lag caused by the long residence time of water within the estuary. The Tagus turbid plume was found to be smaller under northerly and easterly winds, than under southerly and westerly winds. It is suggested that upwelling favoring winds provoke the offshore movement of the plume material with a rapidly decrease in turbidity values whereas downwelling favoring winds retain plume material in the north coast close to the Tagus mouth. Eastern cross-shore (oceanward) winds spread the plume seaward and to the north following the coast geometry, whereas western cross-shore (landward) winds keep the plume material in both alongshore directions occupying a large part of the area enclosed by the bay. Low tides produce larger and more turbid plumes than high tides. In terms of fortnightly periodicity, the maximum plume extension corresponding to the highest turbidity is observed during and after spring tides. Minimum plume extension associated with the lowest turbidity occurs during and after neap tides.
- Published
- 2017
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