97 results on '"H. Garcia"'
Search Results
2. Global travertine deposition modulated by oscillations in climate
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Victor H. Garcia, Amy E. Wagler, L. Ma, and Jason W. Ricketts
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Arts and Humanities (miscellaneous) ,Earth and Planetary Sciences (miscellaneous) ,Paleontology ,Atmospheric sciences ,Deposition (chemistry) ,Geology - Published
- 2019
3. Global transcriptomic analysis of a murine osteocytic cell line subjected to spaceflight
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Margaret Eberle, Yuhei Uda, Chris Adamson, Forest Lai, Joseph H Garcia, Louis C. Gerstenfeld, Paola Divieti Pajevic, Sean Dougherty, Keertik Fulzele, Amira I. Hussein, Lowell Misener, Jordan M Spatz, and Chris Dedic
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0301 basic medicine ,Cell type ,Biology ,Spaceflight ,Mechanotransduction, Cellular ,Osteocytes ,Biochemistry ,law.invention ,Transcriptome ,Mice ,03 medical and health sciences ,Oxygen Consumption ,0302 clinical medicine ,Downregulation and upregulation ,law ,Bone cell ,Genetics ,medicine ,Animals ,Mechanotransduction ,Molecular Biology ,Mechanosensation ,Osteoblast ,Space Flight ,Cell biology ,Glucose ,030104 developmental biology ,medicine.anatomical_structure ,Gene Expression Regulation ,030217 neurology & neurosurgery ,Biotechnology - Abstract
Bone loss is a major health concern for astronauts during long-term spaceflight and for patients during prolonged bed rest or paralysis. Growing evidence suggests that osteocytes, the most abundant cells in the mineralized bone matrix, play a key role in sensing mechanical forces applied to the skeleton and integrating the orchestrated response into subcellular biochemical signals to modulate bone homeostasis. However, the precise molecular mechanisms underlying both mechanosensation and mechanotransduction in late-osteoblast-to-osteocyte cells under microgravity (µG) have yet to be elucidated. To unravel the mechanisms by which late osteoblasts and osteocytes sense and respond to mechanical unloading, we exposed the osteocytic cell line, Ocy454, to 2, 4, or 6 days of µG on the SpaceX Dragon-6 resupply mission to the International Space Station. Our results showed that µG impairs the differentiation of osteocytes, consistent with prior osteoblast spaceflight experiments, which resulted in the downregulation of key osteocytic genes. Importantly, we demonstrate the modulation of critical glycolysis pathways in osteocytes subjected to microgravity and discovered a set of mechanical sensitive genes that are consistently regulated in multiple cell types exposed to microgravity suggesting a common, yet to be fully elucidated, genome-wide response to microgravity. Ground-based simulated microgravity experiments utilizing the NASA rotating-wall-vessel were unable to adequately replicate the changes in microgravity exposure highlighting the importance of spaceflight missions to understand the unique environmental stress that microgravity presents to diverse cell types. In summary, our findings demonstrate that osteocytes respond to µG with an increase in glucose metabolism and oxygen consumption.
- Published
- 2021
4. VP42.11: Influence of activated complement and coagulation cascades on endothelial cell dysfunction in early onset pre‐eclampsia
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Olga Tura-Ceide, Josep M. Campistol, H. Garcia, E. Gratacós, Ana Paula Dantas, Maribel Diaz-Ricart, L. Youssef, Fatima Crispi, Francesca Crovetto, Miquel Blasco, Joan Carles García-Pagán, Marta Palomo, and Sergi Torramade-Moix
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Eclampsia ,Radiological and Ultrasound Technology ,business.industry ,Obstetrics and Gynecology ,General Medicine ,medicine.disease ,Complement (complexity) ,Endothelial stem cell ,Reproductive Medicine ,Coagulation ,Immunology ,Medicine ,Radiology, Nuclear Medicine and imaging ,business ,Early onset - Published
- 2021
5. Bicavitary effusion in a horse with multicentric lymphoma
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Kenneth Kim, Nobuko Wakamatsu, Shannon D. Dehghanpir, Frank M. Andrews, P. Camacho-Luna, H. Garcia, and Stephen D. Gaunt
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Pathology ,medicine.medical_specialty ,Effusion ,Equine ,business.industry ,Pleural effusion ,Medicine ,Horse ,business ,medicine.disease ,Lymphoma - Published
- 2020
6. Blood-brain barrier disruption and angiogenesis in a rat model for neurocysticercosis
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Rogger P Carmen-Orozco, Charles R. Sterling, Nancy Chile, Manuela Verastegui, Hector H. Garcia, Danitza G Dávila-Villacorta, Graham L. Sutherland, Yudith Cauna, Robert H. Gilman, Rensson H. Céliz, Maria C. Ferrufino-Schmidt, Leandra Bitterfeld, Edson G. Bernal-Teran, and Cesar M. Gavidia
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Vascular Endothelial Growth Factor A ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Angiogenesis ,Biology ,Neurocysticercosis ,Fibroblast growth factor ,VEGF-A ,Article ,Umbilical vein ,Rats, Sprague-Dawley ,angiogenesis ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,Taenia solium ,parasitic diseases ,Human Umbilical Vein Endothelial Cells ,medicine ,Animals ,Humans ,BBB disruption ,Tube formation ,Neovascularization, Pathologic ,neurocysticercosis ,Brain ,Endothelial Cells ,purl.org/pe-repo/ocde/ford#3.01.04 [https] ,Rats ,Fibroblast Growth Factors ,Vascular endothelial growth factor ,Endothelial stem cell ,medicine.drug_formulation_ingredient ,030104 developmental biology ,chemistry ,Blood-Brain Barrier ,Immunoglobulin G ,Blood Vessels ,Immunohistochemistry ,purl.org/pe-repo/ocde/ford#3.04.02 [http] ,030217 neurology & neurosurgery ,T. solium - Abstract
Neurocysticercosis (NCC) is a helminth infection affecting the central nervous system caused by the larval stage (cysticercus) of Taenia solium. Since vascular alteration and blood–brain barrier (BBB) disruption contribute to NCC pathology, it is postulated that angiogenesis could contribute to the pathology of this disease. This study used a rat model for NCC and evaluated the expression of two angiogenic factors called vascular endothelial growth factor (VEGF-A) and fibroblast growth factor (FGF2). Also, two markers for BBB disruption, the endothelial barrier antigen and immunoglobulin G, were evaluated using immunohistochemical and immunofluorescence techniques. Brain vasculature changes, BBB disruption, and overexpression of angiogenesis markers surrounding viable cysts were observed. Both VEGF-A and FGF2 were overexpressed in the tissue surrounding the cysticerci, and VEGF-A was overexpressed in astrocytes. Vessels showed decreased immunoreactivity to endothelial barrier antigen marker and an extensive staining for IgG was found in the tissues surrounding the cysts. Additionally, an endothelial cell tube formation assay using human umbilical vein endothelial cells showed that excretory and secretory antigens of T. solium cysticerci induce the formation of these tubes. This in vitro model supports the hypothesis that angiogenesis in NCC might be caused by the parasite itself, as opposed to the host inflammatory responses alone. In conclusion, brain vasculature changes, BBB disruption, and overexpression of angiogenesis markers surrounding viable cysts were observed. This study also demonstrates that cysticerci excretory-secretory processes alone can stimulate angiogenesis. © 2018 Wiley Periodicals, Inc.
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- 2018
7. Low sensitivity and frequent cross-reactions in commercially available antibody detection ELISA assays forTaenia soliumcysticercosis
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Hector H. Garcia, Louis Jacob, Patricia P. Wilkins, Yesenia Castillo, Javier A. Bustos, Robert H. Gilman, Armando E. Gonzalez, Oscar H. Del Brutto, Isidro Gonzales, and Herbert Saavedra
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0301 basic medicine ,Hymenolepiasis ,030106 microbiology ,030231 tropical medicine ,Neurocysticercosis ,Heterologous ,Enzyme-Linked Immunosorbent Assay ,Immunologic Tests ,Sensitivity and Specificity ,Article ,Serology ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,antibody ,Peru ,Taenia solium ,parasitic diseases ,Animals ,Medicine ,neurocysticercose ,biology ,Immunomagnetic Separation ,business.industry ,cysticercosis ,Public Health, Environmental and Occupational Health ,neurocysticercosis ,Cysticercosis ,medicine.disease ,Virology ,medicine.drug_formulation_ingredient ,Infectious Diseases ,cysticercose ,Antigens, Helminth ,anticorps ,Pérou ,biology.protein ,ELISA ,Parasitology ,Antibody ,business ,purl.org/pe-repo/ocde/ford#3.03.06 [https] - Abstract
Objective To evaluate the diagnostic performance of two commercially available ELISA kits, Novalisa® and Ridascreen® , for the detection of antibodies to Taenia solium, compared to serological diagnosis of neurocysticercosis (NCC) by LLGP-EITB (electro-immunotransfer blot assay using lentil-lectin purified glycoprotein antigens). Methods Archive serum samples from patients with viable NCC (n = 45) or resolved, calcified NCC (n = 45), as well as sera from patients with other cestode parasites (hymenolepiasis, n = 45 and cystic hydatid disease, n = 45), were evaluated for cysticercosis antibody detection using two ELISA kits, Novalisa® and Ridascreen® . All NCC samples had previously tested positive, and all samples from heterologous infections were negative on LLGP-EITB for cysticercosis. Positive rates were calculated by kit and sample group and compared between the two kits. Results Compared to LLGP-EITB, the sensitivity of both ELISA assays to detect specific antibodies in patients with viable NCC was low (44.4% and 22.2%), and for calcified NCC, it was only 6.7% and 4.5%. Sera from patients with cystic hydatid disease were highly cross-reactive in both ELISA assays (38/45, 84.4%; and 25/45, 55.6%). Sera from patients with hymenolepiasis cross-reacted in five cases in one of the assays (11.1%) and in only one sample with the second assay (2.2%). Conclusions The performance of Novalisa® and Ridascreen® was poor. Antibody ELISA detection cannot be recommended for the diagnosis of neurocysticercosis.
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- 2017
8. Transfer of innovation on allergic rhinitis and asthma multimorbidity in the elderly ( <scp>MACVIA</scp> ‐ <scp>ARIA</scp> ) ‐ <scp>EIP</scp> on <scp>AHA</scp> Twinning Reference Site ( <scp>GARD</scp> research demonstration project)
- Author
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Alan Estrada-Cardona, Désirée Larenas-Linnemann, A. A. Cruz, A. Bedbrook, Torsten Zuberbier, B. De Martino, Esben Eller, K. C. Bergmann, A. Farsi, Ana Maria Carriazo, João Fonseca, Manuel Teixeira Veríssimo, Carsten Bindslev-Jensen, S. La Grutta, G. De Feo, Rimantas Stukas, M Doulapsi, Jean-Louis Pépin, Adnan Custovic, Gabrielle L. Onorato, Oliver Pfaar, U. Trama, Timo E. Strandberg, Ana Margarida Pereira, M. Bochenska Marciniak, V. Tibaldi, M. H. Garcia Cruz, Juan Carlos Ivancevich, Alessandro Vatrella, Denis Caillaud, Tuula Vasankari, J. A. Rizzo, Robyn E O'Hehir, Anne Lise Courbis, D. Lauri, Benoit Pugin, José Luis Gálvez-Romero, Juan José Matta-Campos, Jean Bousquet, G. De Vries, Johanna Salimäki, A. Yorgancioglu, A. Ciceran, C. Dario, Luc Colas, W. J. Fokkens, J. Millot-Keurinck, Josep M. Antó, I. Annesi-Maesano, F. Corti, Nick A. Guldemond, Renzo Angles, Arūnas Valiulis, Vicky Kritikos, Martin Wagenmann, J Mullol, G. Canfora, Peter Hellings, M. T. Ventura, Bilun Gemicioglu, Martín Bedolla-Barajas, Elísio Costa, M. Guidacci, Milan Sova, Isabelle Bosse, Jesús Guillermo Espinoza-Contreras, D. Conforti, J. Correia de Sousa, M. Sorlini, Massimo Triggiani, Jorge Maspero, Maciej Kupczyk, Rachel Tan, Jean-François Ferrero, D Caiazza, N. Di Carluccio, O. Kalayci, L. Lewis, Javier Gómez-Vera, Antoine Magnan, J. Farrell, T. Dedeu, I. Bogus-Buczynska, J. Just, Erkka Valovirta, Frederic Viart, Daniel Laune, Marco Nalin, Regina Roller-Wirnsberger, A. Szylling, Caterina Bucca, G. Castellano, Davide Caimmi, V. Stroetmann, Filip Raciborski, Rafael Stelmach, Luiana Hernández-Velázquez, Violeta Kvedariene, E. Bacci, Maurizio Romano, Cemal Cingi, A. C. Pozzi, Marit Westman, I. Young, S. Forti, M. T. Burguete Cabañas, Bolesław Samoliński, Ruta Dubakiene, E. Zernotti, A. Blua, Ioana Agache, B. A. Barreto, João O. Malva, J. Lavrut, Thomas Keil, Miguel Alejandro Medina-Ávalos, C. I. García-Cobas, Jorge A. Luna-Pech, J. F. Fontaine, R. Emuzyte, Biljana Cvetkovski, Ruth Murray, Giovanni Rolla, Antonella Muraro, Jussi Karjalainen, H. Neffen, E Cousein, Claus Bachert, V. Kolek, Magnus Wickman, Elaine Colgan, Mario R. Romano, Miguel A. Sierra, Erik Melén, A. Senn, Paulo Augusto Moreira Camargos, C. Cartier, Jawad Hajjam, Ali Fuat Kalyoncu, S. Shamai, Sinthia Bosnic-Anticevich, L. Cecci, Renaud Louis, Ana Todo-Bom, Rodolphe Bourret, Enrica Menditto, Nikolaos G. Papadopoulos, M. M. Ciaravolo, Emmanuel P. Prokopakis, G. Passalacqua, P. V. Tomazic, Edgardo Jares, C. Robalo-Cordeiro, L. Bertorello, M. Bewick, Roland Buonaiuto, A. Romano, Sîan A Williams, Anabela Mota-Pinto, Marcello Persico, Luigi Napoli, M. Lessa, Ralph Mösges, G. Levato, M. Nogues, Tari Haahtela, Edyta Krzych-Fałta, Janet Rimmer, F. de Blay, A. Zurkuhlen, Ludger Klimek, I. Baroni, Niels H. Chavannes, Faradiba Sarquis Serpa, T. Bieber, E. Asayag, Yves Dauvilliers, Piotr Lacwik, R. M. Cortés-Grimaldo, Piotr Kuna, Cristiana Stellato, A Valero, J. da Silva, M. Illario, S Birov, R. Gerth van Wijk, M. R. Aliberti, Inger Kull, Z. Gutter, Sanna Toppila-Salmi, Gérard Dray, Sylvie Arnavielhe, Victoria Cardona, M. Morais-Almeida, Guy Joos, S. Di Capua Ercolano, J. Coll, M. van Eerd, C. Wanscher, N. Khaltaev, Agnieszka Lipiec, Mónica Rodríguez-González, Oscar Mayora, Pascal Demoly, G. Moda, S. Palkonen, I. Lieten, and B. De Oliviera
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Gerontology ,Allergy ,Carat ,medicine.medical_specialty ,Visual analogue scale ,business.industry ,Immunology ,Alternative medicine ,medicine.disease ,Comorbidity ,03 medical and health sciences ,0302 clinical medicine ,Quality of life (healthcare) ,030228 respiratory system ,medicine ,Physical therapy ,Immunology and Allergy ,Multimorbidity ,030212 general & internal medicine ,business ,health care economics and organizations ,Asthma - Abstract
The overarching goals of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) are to enable European citizens to lead healthy, active and independent lives whilst ageing. The EIP on AHA includes 74 Reference Sites. The aim of this study was to transfer innovation from an app developed by the MACVIA-France EIP on AHA reference site (Allergy Diary) to other reference sites. The phenotypic characteristics of rhinitis and asthma multimorbidity in adults and the elderly will be compared using validated information and communication technology (ICT) tools (i.e. the Allergy Diary and CARAT: Control of Allergic Rhinitis and Asthma Test) in 22 Reference Sites or regions across Europe. This will improve the understanding, assessment of burden, diagnosis and management of rhinitis in the elderly by comparison with an adult population. Specific objectives will be: (i) to assess the percentage of adults and elderly who are able to use the Allergy Diary, (ii) to study the phenotypic characteristics and treatment over a 1-year period of rhinitis and asthma multimorbidity at baseline (cross-sectional study) and (iii) to follow-up using visual analogue scale (VAS). This part of the study may provide some insight into the differences between the elderly and adults in terms of response to treatment and practice. Finally (iv) work productivity will be examined in adults.
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- 2017
9. Three-dimensional numerical modeling of the Bulle effect: the nonlinear distribution of near-bed sediment at fluvial diversions
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Som Dutta, Pablo Tassi, Dongchen Wang, and Marcelo H. Garcia
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010504 meteorology & atmospheric sciences ,Scale (ratio) ,0208 environmental biotechnology ,Geography, Planning and Development ,Flow (psychology) ,Fluvial ,Sediment ,02 engineering and technology ,Mechanics ,Solver ,01 natural sciences ,6. Clean water ,020801 environmental engineering ,Current (stream) ,Earth and Planetary Sciences (miscellaneous) ,Reynolds-averaged Navier–Stokes equations ,Geomorphology ,Geology ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Communication channel - Abstract
Bulle-Effect is a phenomenon in which a disproportionately higher amount of near-bed sediment load at a fluvial diversion moves into the diverted channel, even for cases in which the proportion of water (with respect to the main flow) entering the diversion channel is relatively small. This phenomenon has wide ranging implications for both engineered and natural systems; from efficient design of channels to redirect water and sediment for reclaiming sinking deltas, designing navigational channels that do not need frequent dredging, to morphological evolution of river bifurcations. The first ever, and one of the most extensive set of experiments conducted to explore this phenomenon, were conducted by Bulle in 1926. In the current study the experiments conducted by Bulle have been simulated using an open-source, free-surface finite-element based hydrodynamic solver. Main objectives were to explore to what extent the complex phenomenon of Bulle-Effect at the scale of a laboratory experiment can be simulated accurately using Reynolds-Averaged Navier-Stokes (RANS) based hydrodynamic solver, and to understand the details of the hydrodynamics that Bulle could not analyze through his experiments. The hydrodynamics captured by the simulations were found to match the observations made by Bulle through his experiments, and the distributions of sediment at the diversion predicted by the numerical simulations were found to match the general trend observed in the laboratory experiments. The results from the numerical simulations were also compared with existing one-dimensional models for sediment distribution at bifurcations, and the three-dimensional numerical model was found to perform appreciably better. This is expected due to the complex flow features at the diversion, which can only be captured satisfactorily using a three-dimensional hydrodynamic model.
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- 2017
10. Length scales and statistical characteristics of outer bank roughness for large elongate meander bends: The influence of bank material properties, floodplain vegetation and flow inundation
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James L. Best, Marcelo H. Garcia, Jorge D. Abad, Bruce L. Rhoads, Eddy J. Langendoen, Mick Ursic, and Kory Konsoer
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geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Floodplain ,0208 environmental biotechnology ,Geography, Planning and Development ,Elevation ,02 engineering and technology ,Surface finish ,01 natural sciences ,020801 environmental engineering ,Echo sounding ,Roughness length ,Subaerial ,Earth and Planetary Sciences (miscellaneous) ,Meander ,Surface roughness ,Geomorphology ,Geology ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
This paper explores the length scales and statistical characteristics of form roughness along the outer banks of two elongate bends on a large meandering river through investigation of topographic variability of the bank face. The analysis also examines how roughness varies over the vertical height of the banks and when the banks are exposed subaerially and inundated during flood stage. Detailed data on the topography of the outer banks were obtained subaerially using terrestrial LiDAR during low flow conditions and subaqueously using multibeam echo sounding (MBES) during near-bankfull conditions. The contributions of various length scales of topographic irregularity to roughness for subaerial conditions were evaluated for different elevation contours on the bank faces using Hilbert-Huang Transform (HHT) spectral analysis. Statistical characteristics for discrete areas on the bank faces were determined by calculating the root-mean-square of normal distances from a TIN surface. Results of the HHT analysis show that the characteristics of roughness along bank faces composed primarily of non-cohesive sediment, and eroding into cropland, vary with bank elevation and exhibit a dominant range of roughness length scales (~15-50 m). On the other hand, bank faces composed predominantly of cohesive material and carved into a forested floodplain have relatively uniform topographic roughness characteristics over the vertical extent of the bank face and do not exhibit a dominant roughness length scale or range of length scales. Additionally, comparison between local surface roughness for subaerial versus subaqueous conditions shows that roughness decreases considerably when the banks are submerged, most likely because of the removal of vegetation and eradication of small-scale erosional features in non-cohesive bank materials by flow along the bank face. Thus, roughness appears to be linked to the hydraulic conditions affecting the bank, at least relative to conditions that develop when banks are exposed subaerially.
- Published
- 2017
11. Hydraulic Evaluation of the Design and Operation of Ancient Rome's Anio Novus Aqueduct
- Author
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Marcelo H. Garcia, Davide Motta, Duncan Keenan-Jones, and Bruce W. Fouke
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Hydrology ,Archeology ,History ,geography ,geography.geographical_feature_category ,060102 archaeology ,0208 environmental biotechnology ,Flow (psychology) ,Aqueduct ,06 humanities and the arts ,02 engineering and technology ,Ancient Rome ,020801 environmental engineering ,Hydraulic simulation ,Carrying capacity ,0601 history and archaeology ,Geotechnical engineering ,Flow depth ,Channel (geography) ,Geology - Abstract
This paper evaluates conveyance and flow characteristics for the Anio Novus, the aqueduct bringing water from the greatest distance to ancient Rome. Travertine accumulations, deposited from water on floor and walls, were used to reconstruct the flow rate and associated spatial and temporal variations. Hydraulic quantities (e.g., flow depth and velocity) markedly varied over the course of the aqueduct, implying that constraints such as topography and construction techniques were combined with hydraulic considerations to determine the aqueduct layout. Design practices differed along the aqueduct and channel size design was not based exclusively on anticipated carrying capacity, tending towards larger-than-necessary design based on experience.
- Published
- 2017
12. The bubble bursts for cavitation in natural rivers: laboratory experiments reveal minor role in bedrock erosion
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Paul A. Carling, M. M. Perillo, Marcelo H. Garcia, and James L. Best
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geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Engineering structures ,Bedrock ,Bubble ,Geography, Planning and Development ,010502 geochemistry & geophysics ,01 natural sciences ,Abrasion (geology) ,Flume ,Cavitation ,Earth and Planetary Sciences (miscellaneous) ,Geotechnical engineering ,Cavitation erosion ,Geology ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Bed load - Abstract
The erosion of rock-bedded channels generally is considered a slow process caused mainly by abrasion due to bedload or suspended sediments, but the mechanisms of rapid erosion remain unclear. Cavitation is a clear-fluid erosive process, well known for its effect on engineering structures, when water vapour bubbles collapse and the resultant pressure shocks erode the boundary. However, although the occurrence of cavitation erosion in natural watercourses has long been a matter of debate, as yet there are no incontrovertible examples of cavitation damage to natural river beds. Using flume experiments, we show for the first time that only weakly-cavitating clear-water flows can occur for the range of flow velocities observed in rivers, and these do not erode medium-hardness rocks after 68 hours. During this time period, only a very soft rock featured erosional marks due to dissolution. Thus, our results cast significant doubt on the likelihood of identifying cavitation damage in most rivers, and provide pointers to those river systems that might be investigated further to identify cavitation erosion. Copyright © 2016 John Wiley & Sons, Ltd.
- Published
- 2017
13. Monitoring the outcomes of interventions against Taenia solium : options and suggestions
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Marshall W. Lightowlers, Meritxell Donadeu, Bernadette Abela-Ridder, Charles G. Gauci, and Hector H. Garcia
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0301 basic medicine ,taeniasis ,medicine.medical_specialty ,Diagnostic methods ,Swine ,diagnosis ,030231 tropical medicine ,Immunology ,Neurocysticercosis ,Psychological intervention ,Antibodies, Protozoan ,Review Article ,03 medical and health sciences ,0302 clinical medicine ,Taenia solium ,parasitic diseases ,medicine ,Animals ,Humans ,Taeniasis ,Intensive care medicine ,Review Articles ,Swine Diseases ,business.industry ,Antinematodal Agents ,cysticercosis ,neurocysticercosis ,Cysticercosis ,030108 mycology & parasitology ,medicine.disease ,Porcine cysticercosis ,3. Good health ,Surgery ,medicine.drug_formulation_ingredient ,Benzimidazoles ,Parasitology ,Critical assessment ,business ,control - Abstract
Summary There is an increasing interest in reducing the incidence of human neurocysticercosis, caused by infection with the larval stage of Taenia solium. Several intervention trials are currently assessing various options for control of T. solium transmission. A critical aspect of these trials will be the evaluation of whether the interventions have been successful. However, there is no consensus about the most appropriate or valuable methods that should be used. Here, we undertake a critical assessment of the diagnostic tests which are currently available for human T. solium taeniasis and human and porcine cysticercosis, as well as their suitability for evaluation of intervention trial outcomes. Suggestions are made about which of the measures that are available for evaluation of T. solium interventions would be most suitable, and which methodologies are the most appropriate given currently available technologies. Suggestions are also made in relation to the most urgent research needs in order to address deficiencies in current diagnostic methods.
- Published
- 2016
14. Possible Involvement of the Inhibition of NF-κB Factor in Anti-Inflammatory Actions That Melatonin Exerts on Mast Cells
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Carmen González-Yanes, H. Garcia-Moreno, Juan R. Calvo, and M.D. Maldonado
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0301 basic medicine ,medicine.medical_specialty ,Inflammation ,Biology ,Pharmacology ,Biochemistry ,Melatonin ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Immune system ,Internal medicine ,medicine ,Molecular Biology ,NF-κB ,Cell Biology ,030104 developmental biology ,Endocrinology ,Mechanism of action ,chemistry ,Phorbol ,Tumor necrosis factor alpha ,medicine.symptom ,Signal transduction ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Melatonin is a molecule endogenously produced in a wide variety of immune cells, including mast cells (RBL-2H3). It exhibits immunomodulatory, anti-inflammatory and anti-apoptotic properties. The physiologic mechanisms underlying these activities of melatonin have not been clarified in mast cells. This work is designed to determine the anti-inflammatory effect and mechanism of action of melatonin on activated mast cells. RBL-2H3 were pre-treated with exogenous melatonin (MELx) at physiological (100nM) and pharmacological (1 mM) doses for 30 min, washed and activated with PMACI (phorbol 12-myristate 13-acetate plus calcium ionophore A23187) for 2 h and 12 h. The data shows that pre-treatment of MELx in stimulated mast cells, significantly reduced the levels of endogenous melatonin production (MELn), TNF-α and IL-6. These effects are directly related with the MELx concentration used. MELx also inhibited IKK/NF-κB signal transduction pathway in stimulated mast cells. These results indicate a molecular basis for the ability of melatonin to prevent inflammation and for the treatment of allergic inflammatory diseases through the down-regulation of mast cell activation. J. Cell. Biochem. 117: 1926-1933, 2016. © 2016 Wiley Periodicals, Inc.
- Published
- 2016
15. OC07.11: Metabolomic profiling of pathophysiological pathways in early onset severe pre‐eclampsia
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Eduard Gratacós, L. Youssef, H. Garcia, F. Crispi, Maribel Diaz-Ricart, N. Canela, Joan Carles García-Pagán, Olga Tura-Ceide, Ana Paula Dantas, and Josep M. Campistol
- Subjects
Eclampsia ,Radiological and Ultrasound Technology ,business.industry ,Obstetrics and Gynecology ,General Medicine ,Bioinformatics ,medicine.disease ,Pathophysiology ,Metabolomic profiling ,Reproductive Medicine ,Medicine ,Radiology, Nuclear Medicine and imaging ,business ,Early onset - Published
- 2020
16. Dimethylmaleimide: a new reagent for protein bioconjugation
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Gregory A. Weiss, Andrew Chu, Mark B. Richardson, Joseph H Garcia, Sudipta Majumdar, and Rebekah P. Dyer
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Bioconjugation ,Chemistry ,Reagent ,Genetics ,Molecular Biology ,Biochemistry ,Combinatorial chemistry ,Biotechnology - Published
- 2018
17. Axonal swellings and spheroids: a new insight into the pathology of neurocysticercosis
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Alan Mejia Maza, Danitza G Dávila-Villacorta, Manuela Verastegui, Hector H. Garcia, Cesar M. Gavidia, Javier Mamani, Gino Castillo, Emma S Carter, Armando E. Gonzalez, Robert H. Gilman, Joseph Alroy, Charles R. Sterling, Jemina D Morales, Randy Woltjer, and Rogger P Carmen-Orozco
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0301 basic medicine ,pig ,Pathology ,Swine ,Neurocysticercosis ,microglia ,nerve fiber degeneration ,amyloid precursor protein ,animal cell ,Rats, Sprague-Dawley ,Pathogenesis ,Epilepsy ,brain tissue ,0302 clinical medicine ,Taenia solium ,Amyloid precursor protein ,rat ,oncosphere ,brain disease ,General Neuroscience ,phagocyte ,Brain ,neurocysticercosis ,Pathophysiology ,medicine.drug_formulation_ingredient ,spheroid cell ,embryonic structures ,immunohistochemistry ,parenchyma ,meninx ,immunoreactivity ,medicine.medical_specialty ,Neurofilament ,animal experiment ,spheroids ,Biology ,neurofilament ,Article ,Pathology and Forensic Medicine ,animal tissue ,03 medical and health sciences ,brain histology ,astrocyte ,Spheroids, Cellular ,parasitic diseases ,medicine ,Animals ,Humans ,controlled study ,T. solium oncospheres ,human ,Letters to the Editor ,neuropathology ,nonhuman ,animal model ,purl.org/pe-repo/ocde/ford#3.01.04 [https] ,medicine.disease ,Axons ,human tissue ,Rats ,purl.org/pe-repo/ocde/ford#3.01.09 [https] ,030104 developmental biology ,biology.protein ,Axoplasmic transport ,Neurology (clinical) ,APP ,030217 neurology & neurosurgery - Abstract
Neurocysticercosis is a parasitic brain disease caused by the larval form (Cysticercus cellulosae) of the Taenia solium and is the leading cause of preventable epilepsy world-wide. However, the pathophysiology and relation to the wide range of clinical features remains poorly understood. Axonal swelling is emerging as an important early pathological finding in multiple neurodegenerative diseases and causes of brain injury, but has not been well-described in neurocysticercosis. Histological analysis was performed on human, rat and porcine NCC brain specimens to identify axonal pathology. Rat infection was successfully carried out via two routes of inoculation: direct intracranial injection and oral feeding. Extensive axonal swellings, in the form of spheroids, were observed in both humans and rats and to a lesser extent in pigs with NCC. Spheroids demonstrated increased immunoreactivity to amyloid precursor protein and neurofilament indicating probable impairment of axonal transport. These novel findings demonstrate that spheroids are present in NCC which is conserved across species. Not only is this an important contribution towards understanding that pathogenesis of NCC, but it also provides a model to analyze the association of spheroids with specific clinical features and to investigate the reversibility of spheroid formation with antihelmintic treatment.
- Published
- 2018
18. Automatic testbed with a visual motion tracking system for airborne wind energy applications
- Author
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I. Castro‐Fernández, F. DeLosRíos‐Navarrete, R. Borobia‐Moreno, M. Fernández‐Jiménez, H. García‐Cousillas, M. Zas‐Bustingorri, A. T. Ghobaissi, F. López‐Vega, K. Best, R. Cavallaro, and G. Sánchez‐Arriaga
- Subjects
artificial neural network ,Kalman filter ,open‐loop control ,rigid‐framed delta kite ,visual motion tracking ,Renewable energy sources ,TJ807-830 - Abstract
Abstract The architecture and a flight test campaign of a small‐scale testbed aimed at aerodynamic and dynamic characterization of airborne wind energy systems are presented. The testbed involves a two‐line rigid‐framed delta kite and an automatic ground station for the lateral control of the kite and reel‐in/reel‐out of the two tethers. The environment, and the states of the kite, the tethers and the actuators are measured by a set of on‐ground and onboard sensors that include, among others, an inertial measurement unit, GNSS receivers, load cells, actuator encoders, a wind station, and a visual motion tracking (VMT) system based on three cameras and an artificial neural network (YOLOv2). The results of a 5‐min flight, including the take‐off, cross‐wind flight, and landing, were used to analyze the capabilities of the testbed. It was shown that the time derivative of the kite course angle exhibits a linear correlation with both the delayed steering input and the delayed differential tether tension, being the dispersion lower for the latter. The intrinsic and extrinsic calibrations proposed for the VMT system led to a good agreement between the estimation of the kite position and course angle provided by the VMT system and the onboard computer. Moreover, although the YOLOv2 algorithm failed in the detection of the kite within around 5% of the images, the simultaneous non‐detection from the three cameras was below 0.1% during the full flight. Such a reliability suggests that a VMT system can be used as a redundant or backup sensor for the GNSS.
- Published
- 2023
- Full Text
- View/download PDF
19. A unified model for bedform development and equilibrium under unidirectional, oscillatory and combined-flows
- Author
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Marcelo H. Garcia, M. M. Perillo, Tomohiro Takagawa, James L. Best, Tomohiro Sekiguchi, and Miwa Yokokawa
- Subjects
Flume ,Bedform ,Flow conditions ,Stratigraphy ,Flow (psychology) ,Sediment ,Geology ,Sedimentary rock ,Geometry ,Sediment transport ,Geomorphology ,Sedimentary structures - Abstract
The development of bedforms under unidirectional, oscillatory and combined-flows results from temporal changes in sediment transport, flow and morphological response. In such flows, the bedform characteristics (for example, height, wavelength and shape) change over time, from their initiation to equilibrium with the imposed conditions, even if the flow conditions remain unchanged. These variations in bedform morphology during development are reflected in the sedimentary structures preserved in the rock record. Hence, understanding the time and morphological development in which bedforms evolve to an equilibrium stage is critical for informed reconstruction of the ancient sedimentary record. This article presents results from a laboratory flume study on bedform development and equilibrium development time conducted under purely unidirectional, purely oscillatory and combined-flow conditions, which aimed to test and extend an empirical model developed in past work solely for unidirectional ripples. The present results yield a unified model for bedform development and equilibrium under unidirectional, oscillatory and combined-flows. The experimental results show that the processes of bedform genesis and growth are common to all types of flows, and can be characterized into four stages: (i) incipient bedforms; (ii) growing bedforms; (iii) stabilizing bedforms; and (iv) fully developed bedforms. Furthermore, the development path of bedform; growth exhibits the same general trend for different flow types (for example, unidirectional, oscillatory and combined-flows), bedform size (for example, small versus large ripples), bedform shape (for example, symmetrical or rounded), bedform planform geometry (for example, two-dimensional versus three-dimensional), flow velocities and sediment grain sizes. The equilibrium time for a wide range of bed configurations was determined and found to be inversely proportional to the sediment transport flux occurring for that flow condition.
- Published
- 2014
20. P15.04: Maternal proteomics reveals the involvement of complement and coagulation cascades in early onset pre‐eclampsia
- Author
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Marta Palomo, H. Garcia, E. Gratacós, L. Youssef, Miquel Blasco, J. Garcia Pagan, Josep M. Campistol, Fatima Crispi, A.M. Dantas, and Maribel Diaz-Ricart
- Subjects
Eclampsia ,Radiological and Ultrasound Technology ,business.industry ,Obstetrics and Gynecology ,General Medicine ,Proteomics ,medicine.disease ,Complement (complexity) ,Reproductive Medicine ,Coagulation ,Immunology ,Medicine ,Radiology, Nuclear Medicine and imaging ,business ,Early onset - Published
- 2019
21. High levels of melatonin generated during the brewing process
- Author
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M.D. Maldonado, H. Garcia-Moreno, and Juan R. Calvo
- Subjects
Antioxidant ,medicine.medical_treatment ,education ,Melatonin ,Endocrinology ,Nutraceutical ,Yeasts ,medicine ,Food science ,Analysis of Variance ,business.industry ,Chemistry ,Beer ,food and beverages ,Hordeum ,Yeast ,High alcohol ,Fermentation ,behavior and behavior mechanisms ,Brewing ,business ,human activities ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Beer is a beverage consumed worldwide. It is produced from cereals (barley or wheat) and contains a wide array of bioactive phytochemicals and nutraceutical compounds. Specifically, high melatonin concentrations have been found in beer. Beers with high alcohol content are those that present the greatest concentrations of melatonin and vice versa. In this study, gel filtration chromatography and ELISA were combined for melatonin determination. We brewed beer to determine, for the first time, the beer production steps in which melatonin appears. We conclude that the barley, which is malted and ground in the early process, and the yeast, during the second fermentation, are the largest contributors to the enrichment of the beer with melatonin.
- Published
- 2012
22. Neurocysticercosis: is serology useful in the absence of brain imaging?
- Author
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Robert H. Gilman, Silvia Rodriguez, Armando E. Gonzalez, Hector H. Garcia, and Victor C. W. Tsang
- Subjects
business.industry ,Neurocysticercosis ,Public Health, Environmental and Occupational Health ,Cysticercosis ,Disease ,medicine.disease ,Asymptomatic ,Serology ,medicine.drug_formulation_ingredient ,Infectious Diseases ,Neuroimaging ,Taenia solium ,Immunology ,Etiology ,medicine ,Parasitology ,medicine.symptom ,business - Abstract
Neurocysticercosis (NCC) is endemic in most parts of the world and is now recognised as an important contributor to neurological disease. Serological diagnosis of NCC improved greatly in the past two decades and contributed to demonstrating previously unsuspected regions of endemicity. Claims for an accurate serological screening tool for human cysticercosis are frequently raised. However, after symptomatic therapeutics are applied, management of NCC is driven by the characteristics of the central nervous system infection in terms of viability, number, location size and evolutionary stage of parasites, as well as by the resulting inflammation. It is unclear whether, in the absence of neuroimaging, serological confirmation of aetiology of suspected cases (neurologically symptomatic) or detection of asymptomatic cases in population screening would affect their management or prognosis.
- Published
- 2012
23. Sediment mobility and bed armoring in the St Clair River: insights from hydrodynamic modeling
- Author
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Daniel R. Parsons, Xiaofeng Liu, Peter Ashmore, Kevin A. Oberg, Johnathan A. Czuba, Gary Parker, James L. Best, Marcelo H. Garcia, Jose M. Mier, and Bommanna G. Krishnappan
- Subjects
Dredging ,Hydrology ,Flow conditions ,Bedform ,Streamflow ,Geography, Planning and Development ,Earth and Planetary Sciences (miscellaneous) ,Lake ecosystem ,Bathymetry ,Sediment transport ,Geology ,Earth-Surface Processes ,Open-channel flow - Abstract
The lake levels in Lake Michigan-Huron have recently fallen to near historical lows, as has the elevation difference between Lake Michigan-Huron compared to Lake Erie. This decline in lake levels has the potential to cause detrimental impacts on the lake ecosystems, together with social and economic impacts on communities in the entire Great Lakes region. Results from past work suggest that morphological changes in the St Clair River, which is the only natural outlet for Lake Michigan-Huron, could be an appreciable factor in the recent trends of lake level decline. A key research question is whether bed erosion within the river has caused an increase in water conveyance, therefore, contributed to the falling lake level. In this paper, a numerical modeling approach with field data is used to investigate the possibility of sediment movement in the St Clair River and assess the likelihood of morphological change under the current flow regime. A two-dimensional numerical model was used to study flow structure, bed shear stress, and sediment mobility/armoring over a range of flow discharges. Boundary conditions for the numerical model were provided by detailed field measurements that included high-resolution bathymetry and three-dimensional flow velocities. The results indicate that, without considering other effects, under the current range of flow conditions, the shear stresses produced by the river flow are too low to transport most of the coarse bed sediment within the reach and are too low to cause substantial bed erosion or bed scour. However, the detailed maps of the bed show mobile bedforms in the upper St Clair River that are indicative of sediment transport. Relatively high shear stresses near a constriction at the upstream end of the river and at channel bends could cause local scour and deposition. Ship-induced propeller wake erosion also is a likely cause of sediment movement in the entire reach. Other factors that may promote sediment movement, such as ice cover and dredging in the lower river, require further investigation. Copyright © 2012 John Wiley & Sons, Ltd.
- Published
- 2012
24. Cestodes
- Author
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Hector H. Garcia, Juan A. Jimenez, and Hermes Escalante
- Published
- 2011
25. Albendazole-praziquantel interaction in healthy volunteers: kinetic disposition, metabolism and enantioselectivity
- Author
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Hector H. Garcia, Renata Monteiro Lima, Maria Augusta Drago Ferreira, Osvaldo Massaiti Takayanagui, Eduardo Barbosa Coelho, Vera Lucia Lanchote, Teresa Maria de Jesus Ponte Carvalho, and Bruno Jose Dumêt Fernandes
- Subjects
Pharmacology ,Chemistry ,Drug interaction ,Antiparasitic agent ,Crossover study ,Albendazole ,Praziquantel ,Pharmacokinetics ,parasitic diseases ,medicine ,Pharmacology (medical) ,Anthelmintic ,Enantiomer ,medicine.drug - Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Pharmacokinetic interactions between albendazole and praziquantel are based on plasma concentrations of the enantiomeric mixture of both drugs with contradictory data, although the antiparasitic activity arises from (−)-(R)-praziquantel and (+)-albendazole sulfoxide. WHAT THIS STUDY ADDS • The pharmacokinetic interaction between albendazole and praziquantel is enantioselective. Praziquantel increased the plasma concentrations of (+)-albendazole sulfoxide more than those of (−)-albendazole sulfoxide and the administration of albendazole did not change the kinetic disposition of (+)-(S)-praziquantel, but increased the plasma concentration of (−)-(R)-praziquantel. AIM This study investigated the kinetic disposition, metabolism and enantioselectivity of albendazole (ABZ) and praziquantel (PZQ) administered alone and in combination to healthy volunteers. METHODS A randomized crossover study was carried out in three phases (n= 9), in which some volunteers started in phase 1 (400 mg ABZ), others in phase 2 (1500 mg PZQ), and the remaining volunteers in phase 3 (400 mg ABZ + 1500 mg PZQ). Serial blood samples were collected from 0–48 h after drug administration. Pharmacokinetic parameters were calculated using a monocompartmental model with lag time and were analyzed using the Wilcoxon test; P≤ 0.05. RESULTS The administration of PZQ increased the plasma concentrations of (+)-ASOX (albendazole sulphoxide) by 264% (AUC 0.99 vs. 2.59 µg ml−1 h), (−)-ASOX by 358% (0.14 vs. 0.50 µg ml−1 h) and albendazole sulfone (ASON) by 187% (0.17 vs. 0.32 µg ml−1 h). The administration of ABZ did not change the kinetic disposition of (+)-(S)-PZQ (–)-(R)-4-OHPZQ or (+)-(S)-4-OHPZQ, but increased the plasma concentration of (–)-(R)-PZQ by 64.77% (AUC 0.52 vs. 0.86 µg ml−1 h). CONCLUSIONS The pharmacokinetic interaction between ABZ and PZQ in healthy volunteers was demonstrated by the observation of increased plasma concentrations of ASON, both ASOX enantiomers and (–)-(R)-PZQ. Clinically, the combination of ABZ and PZQ may improve the therapeutic efficacy as a consequence of higher concentration of both active drugs. On the other hand, the magnitude of this elevation may represent an increased risk of side effects, requiring, certainly, reduction of the dosage. However, further studies are necessary to evaluate the efficacy and safety of this combination.
- Published
- 2011
26. Disease awareness and knowledge in caregivers of children who had surgery for cystic hydatid disease in Lima, Peru
- Author
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Carlos Guevara, Claudia Taramona, Mardeli Saire-Mendoza, María Magdalena Munguía Reyes, and Hector H. Garcia
- Subjects
medicine.medical_specialty ,business.industry ,Cystic echinococcosis ,Public Health, Environmental and Occupational Health ,Hydatid cyst ,Health knowledge ,medicine.disease ,Echinococcosis ,Surgery ,Infectious Diseases ,El Niño ,Tropical medicine ,medicine ,Parasitology ,Cestode infections ,business - Abstract
Summary Cystic hydatid disease (CHD) is a common cause of lung and liver disease worldwide. Despite Peru being highly endemic, information about the level of knowledge is scarce and poor. A telephone survey was applied to assess the knowledge in the caregivers of patients treated for CHD at a paediatric hospital at Lima, Peru. Of the 26 contacted families, only 5 (20%) answered correctly all seven questions. A higher education degree was associated with correct answers (P = 0.002). Most respondents (17, 65%) incorrectly identified the etiologic agent and mode of transmission. Lack of knowledge is likely a major contributor to maintain the endemicity of disease in Peru. Communication breve Sensibilisation a la maladie et connaissances des soignants d’enfants ayant subi une chirurgie pour la maladie a kystique hydatique a Lima, au Perou La maladie a kyste hydatique est une cause frequente de maladie pulmonaire et hepatique dans le monde. Bien que le Perou soit hautement endemique, des informations sur le niveau des connaissances sont rares et pauvres. Un sondage telephonique a ete applique pour evaluer les connaissances chez les soignants des patients traites pour maladie a kyste hydatique dans un hopital pediatrique a Lima, au Perou. Sur les 26 familles contactees, seules 5 (20%) ont repondu correctement a toutes les sept questions. La possession d’un diplome de l’enseignement superieur a ete associee a de bonnes reponses (p = 0,002). La plupart des repondants (n=17, 65%) ont incorrectement identifie l’agent etiologique et le mode de transmission. Le manque de connaissances est probablement un contributeur majeur au maintien du caractere endemique de la maladie au Perou. Mots-cles: echinococcose, connaissances sur la sante, attitudes, pratique, therapie Comunicacion corta Conocimientos sobre la hidatidosis quistica de cuidadores de ninos que han tenido una intervencion quirurgica por esta enfermedad en Lima, Peru La hidatidosis quistica es una causa comun de enfermedad pulmonar y hepatica en todo el mundo. A pesar de que Peru es un pais con una alta endemicidad, poco se conoce acerca del nivel de informacion de su poblacion. Se realizo una encuesta telefonica para evaluar el nivel de conocimientos entre los cuidadores de pacientes tratados de hidatidosis quistica en un hospital pediatrico en Lima, Peru. De las 26 familias contactadas solo 5 (20%) respondieron correctamente las 7 preguntas. El tener un mayor nivel educativo estaba asociado con el responder correctamente (p = 0.002). La mayoria de los que respondieron incorrectamente (17, 65%) identificaron al agente etiologico y el modo de transmision. La falta de conocimientos es probablemente uno de los factores que mas contribuye al mantenimiento de la endemicidad de esta enfermedad en el Peru. Palabras clave: Equinococosis, conocimientos sanitarios, actitudes, Practica; Terapia
- Published
- 2010
27. Bedload transport and bed resistance associated with density and turbidity currents
- Author
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Benoît Spinewine, Octavio E. Sequeiros, Rick T. Beaubouef, Gary Parker, Tao Sun, and Marcelo H. Garcia
- Subjects
geography ,geography.geographical_feature_category ,Bedform ,Turbidity current ,Stratigraphy ,Sediment ,Geology ,Submarine canyon ,Shields parameter ,Turbidite ,Sediment transport ,Geomorphology ,Bed load - Abstract
Turbidity currents in the ocean are driven by suspended sediment. Yet results from surveys of the modern sea floor and turbidite outcrops indicate that they are capable of transporting as bedload and depositing particles as coarse as cobble sizes. While bedload cannot drive turbidity currents, it can strongly influence the nature of the deposits they emplace. This paper reports on the first set of experiments which focus on bedload transport of granular material by density underflows. These underflows include saline density flows, hybrid saline/turbidity currents and a pure turbidity current. The use of dissolved salt is a surrogate for suspended mud which is so fine that it does not settle out readily. Thus, all the currents can be considered to be model turbidity currents. The data cover four bed conditions: plane bed, dunes, upstream-migrating antidunes and downstream-migrating antidunes. The bedload transport relation obtained from the data is very similar to those obtained for open-channel flows and, in fact, is fitted well by an existing relation determined for open-channel flows. In the case of dunes and downstream-migrating antidunes, for which flow separation on the lee sides was observed, form drag falls in a range that is similar to that due to dunes in sand-bed rivers. This form drag can be removed from the total bed shear stress using an existing relation developed for rivers. Once this form drag is subtracted, the bedload data for these cases collapse to follow the same relation as for plane beds and upstream-migrating antidunes, for which no flow separation was observed. A relation for flow resistance developed for open-channel flows agrees well with the data when adapted to density underflows. Comparison of the data with a regime diagram for field-scale sand-bed rivers at bankfull flow and field-scale measurements of turbidity currents at Monterey Submarine Canyon, together with Shields number and densimetric Froude number similarity analyses, provide strong evidence that the experimental relations apply at field scale as well.
- Published
- 2010
28. Thermo- and pH-sensitive hydrogels based on 2-(2-methoxyethoxy)ethyl methacrylate and methacrylic acid
- Author
-
Jose H. Garcia, Rodrigo París, and Isabel Quijada-Garrido
- Subjects
Materials science ,Polymers and Plastics ,Comonomer ,Organic Chemistry ,Swelling capacity ,Methacrylate ,Polyelectrolyte ,chemistry.chemical_compound ,Methacrylic acid ,chemistry ,Self-healing hydrogels ,Polymer chemistry ,otorhinolaryngologic diseases ,Materials Chemistry ,medicine ,Swelling ,medicine.symptom ,Drug carrier - Abstract
Hydrogels based on commercially available 2-(2-methoxyethoxy)ethyl methacrylate (MEO2MA), with methacrylic acid (MAA) as comonomer, are studied. The incorporation of an ionizable monomer, such as MAA, in a thermosensitive system leads to the formation of hydrogels able to respond to pH and temperature according to their monomeric composition. Thus, at low pH, the acid groups of MAA are protonated, and they do not contribute to increase the hydrophilic balance, and collapse of the hydrogels occurs around room temperature. For temperatures below that of collapse, the degree of swelling increases with increasing MEO2MA content. In contrast, at neutral or basic pH, the ionization of the acid groups contributes to increase the hydrophilicity and the osmotic pressure, leading to polyelectrolyte behaviour. In this regime, the swelling capacity increases and the thermosensitivity decreases with increasing MAA content in the hydrogels. These properties make poly(MEO2MA-co-MAA) hydrogels suitable candidates for use in oral controlled delivery of hydrophobic drugs. This possibility is explored using ibuprofen as a model drug, after a complete study of the swelling kinetics. Copyright © 2010 Society of Chemical Industry
- Published
- 2010
29. A new method for the detection of microorganisms in blood cultures: Part I. Theoretical analysis and simulation of blood culture processes
- Author
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German F. Leparc, Jennifer M. Smith, Yulia M. Serebrennikova, Luis H. Garcia-Rubio, and Debra E. Huffman
- Subjects
Engineering ,medicine.diagnostic_test ,business.industry ,General Chemical Engineering ,Microorganism ,Mineralogy ,Early detection ,Reflectivity ,Blood chemistry ,medicine ,Blood culture ,sense organs ,Biochemical engineering ,business - Abstract
The physical and chemical changes occurring in blood as a consequence of microbial activity can be used as quantitative indicators of the presence of microorganisms in blood cultures. This paper reports on the theoretical analysis and computer simulation of the changes in the physical and chemical properties of blood expected as a result of the presence of microorganisms and explores the possibilities of spectrophotometric systems for the early detection of pathogens. It is concluded that multi-wavelength reflectance methods are suitable and that the approach reported herein can lead to considerable simplifications and cost reduction of blood culture systems.
- Published
- 2008
30. 2D stream hydrodynamic, sediment transport and bed morphology model for engineering applications
- Author
-
Jorge D. Abad, Marcelo H. Garcia, and Gustavo C. Buscaglia
- Subjects
Physics::Fluid Dynamics ,Bedform ,Turbulence ,Multiphase flow ,Mean flow ,Suspended load ,Geotechnical engineering ,Secondary flow ,Sediment transport ,Geology ,Water Science and Technology ,Bed load - Abstract
A 2D depth-averaged hydrodynamic, sediment transport and bed morphology model named STREMR HySeD is presented. The depth-averaged sediment transport equations are derived from the 3D dilute, multiphase, flow equations and are incorporated into the hydrodynamic model STREMR. The hydrodynamic model includes a two-equation turbulence model and a correction for the mean flow due to secondary flows. The suspended sediment load can be subdivided into different size classes using the continuum (two-fluid) approach; however, only one bed sediment size is used herein. The validation of the model is presented by comparing the suspended sediment transport module against experimental measurements and analytical solutions for the case of equilibrium sediment-laden in a transition from a rigid bed to a porous bed where re-suspension of sediment is prevented. On the other hand, the bed-load sediment transport and bed evolution numerical results are compared against bed equilibrium experimental results for the case of a meander bend. A sensitivity analysis based on the correction for secondary flow on the mean flow including the effect of secondary flow on bed shear stresses direction as well as the downward acceleration effect due to gravity on transverse bed slopes is performed and discussed. In general, acceptable agreement is found when comparing the numerical results obtained with STREMR HySeD against experimental measurements and analytical solutions.
- Published
- 2008
31. Interpretation of Light Scattering Spectra of Dispersions - A Hybrid Approach to Account for Interparticle Interactions
- Author
-
Luis H. Garcia-Rubio and Suresh N. Thennadil
- Subjects
Chemistry ,Scattering ,Monte Carlo method ,Percus–Yevick approximation ,General Chemistry ,Condensed Matter Physics ,Light scattering ,Charged particle ,Computational physics ,Particle ,General Materials Science ,Statistical physics ,Dispersion (chemistry) ,Structure factor - Abstract
The problem of extracting quantitative information on individual particle properties from spectroscopic measurements conducted at concentrations where particle interactions become significant is of great industrial and theoretical importance. For dispersions of charged particles, this can happen at fairly low concentrations. The effect of the fluid (slurry) structure has to be taken into account to interpret the light scattering spectra of such dispersions. In this paper, a hybrid method that addresses the effect of the fluid structure is proposed. The hybrid approach describes the fluid structure by relating the “effective” Percus-Yevick hard-sphere parameters to the system parameters using empirical models. The feasibility of this approach is examined through a theoretical study with data generated by Monte Carlo simulations of a monodisperse dispersion of charged spherical particles using realistic interaction potentials under single scattering conditions.
- Published
- 2007
32. Identification of nucleation loci in emulsion polymerization processes. I. New information from spectroscopy studies
- Author
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Vineet Shastry and L. H. Garcia-Rubio
- Subjects
education.field_of_study ,Polymers and Plastics ,Radical polymerization ,Population ,technology, industry, and agriculture ,Nucleation ,Emulsion polymerization ,Locus (genetics) ,General Chemistry ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Monomer ,Ultraviolet visible spectroscopy ,chemistry ,Chemical physics ,Polymer chemistry ,Materials Chemistry ,education ,Spectroscopy - Abstract
Particle nucleation is the forcing function in emulsion polymerization reactions and as such it plays a significant role in the development of most of the properties of the final latex. The locus of nucleation in emulsion polymerization remains a contentious issue. Recent developments in the spectroscopy of emulsions strongly suggest that the locus of particle nucleation is a population of small nano-droplets of size range between 30–100 nanometers in diameter. These nano-droplets are generated independently of the rate of initiator decomposition and appear to be functions only of the emulsification conditions. In this paper the simulation studies leading to the identification of the nano-droplet population are described. The theoretical evidence suggesting that the nano-droplets are the main loci of particle nucleation is presented and along with the recommendations for the experimental work. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2847–2857, 2006
- Published
- 2006
33. Identification of nucleation loci in emulsion polymerization processes. II. A systematic study of liquid–liquid emulsions
- Author
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Vineet Shastry and L. H. Garcia-Rubio
- Subjects
education.field_of_study ,Polymers and Plastics ,Population ,Radical polymerization ,Nucleation ,Emulsion polymerization ,General Chemistry ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Monomer ,chemistry ,Chemical engineering ,Phase (matter) ,Polymer chemistry ,Emulsion ,Materials Chemistry ,education ,Spectroscopy - Abstract
Identification of the main nucleation sites and characterizing them in terms of their size and composition is prime objective of this research effort. Different nucleation sites have been proposed as the most likely nucleation sites by various researchers. Recent advances in the development of the spectroscopic techniques enable comprehensive characterization of the emulsion at the beginning of the reaction. In this paper, we present the experimental evidence of the existence of a previously unidentified nano-droplet population of size range 30 to 100 nm in diameter using spectroscopy. Presence of about seventy to eighty percent of the dispersed phase in the nano-droplet population and large interfacial area make them the most probable particle nucleation loci in emulsion polymerization processes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2858–2866, 2006
- Published
- 2006
34. Growth behavior of microorganisms using UV-Vis spectroscopy:Escherichia coli
- Author
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Luis H. Garcia-Rubio and Catalina E. Alupoaei
- Subjects
Spectral signature ,medicine.diagnostic_test ,Chemistry ,Analytical chemistry ,Bioengineering ,Applied Microbiology and Biotechnology ,Spectral line ,Quantitative Biology::Cell Behavior ,Absorbance ,Wavelength ,Ultraviolet visible spectroscopy ,Chemical physics ,Spectrophotometry ,medicine ,Spectroscopy ,Absorption (electromagnetic radiation) ,Biotechnology - Abstract
Multiwavelength transmission spectra of microorganisms and cell suspensions consist of combined absorption and scattering phenomena resulting from the interaction of light with microorganisms or cells typically suspended in a nonabsorbing media. The distribution of intensities as a function of wavelength depends on the size, shape, and optical properties of the sample. The optical properties are functions of the chemical composition and the state of aggregation, or association, of the chromophoric groups contained in the microorganisms. This article explores the growth behavior of Escherichia coli from the perspective of multiwavelength UV-Vis spectroscopy. Experimentally, it is demonstrated that the spectral signatures of the microorganism evolve as a function of time. It is also demonstrated that the spectral changes observed during growth are consistent with data reported elsewhere. From the theoretical point of view, it is demonstrated that the spectral signatures can be adequately represented with an interpretation model based on light-scattering theory. The parameters from the interpretation model reflect changes in size and chemical composition known to take place in the microorganisms during growth.
- Published
- 2004
35. A large silent cysticercus occupying most of the medulla oblongata
- Author
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H. Saavedra, C. Salas, H. H. Garcia, J. P. Meneses, and D. Esteban
- Subjects
parasitic infections ,Pathology ,medicine.medical_specialty ,purl.org/pe-repo/ocde/ford#3.02.25 [https] ,business.industry ,cysticercosis ,030231 tropical medicine ,Neurocysticercosis ,neurocysticercosis ,Cysticercosis ,Cysticercus ,medicine.disease ,03 medical and health sciences ,medicine.drug_formulation_ingredient ,0302 clinical medicine ,Neurology ,parasitic diseases ,Taenia solium ,Medulla oblongata ,Medicine ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,seizures - Abstract
Neurocysticercosis (NCC) is the infectionof the central nervous system by cysts(larvae) of Taenia solium, a relevant pub-lic health issue in low-income countriesand nowadays found in most of theworld. NCC cysts most commonly locatein the gray-white matter border of thecerebral hemispheres, although they canbe found in ventricles, subarachnoidspaces, cerebellum or spine. The locationof the cysts defines the clinical presenta-tion, i.e. seizures in the case of parenchy-mal brain cysticercosis, intracranialhypertension in subarachnoid or ventricu-lar cysticercosis. A cyst in an unusuallocation, such as the brainstem, may pres-ent a diagnostic and therapeutic challenge. We report a patient with a cysticerco-sis cyst in the medulla oblongata, withgross displacement of its anatomicalstructures but minimal clinical expression.
- Published
- 2016
36. Threshold for particle entrainment into suspension
- Author
-
Marcelo H. Garcia, Fabián López, and Yarko Niño
- Subjects
Turbulence ,Stratigraphy ,Flow (psychology) ,Laminar sublayer ,Geology ,Mechanics ,Suspension (chemistry) ,Physics::Fluid Dynamics ,Settling ,Particle ,Geotechnical engineering ,Shear velocity ,Entrainment (chronobiology) - Abstract
Laboratory observations regarding the limit conditions for particle entrainment into suspension are presented. A high-speed video system was used to investigate conditions for the entrainment of sediment particles and glass beads lying over a smooth boundary as well as over a rough bed. The results extend experimental conditions of previous studies towards finer particle sizes. A criterion for the limit of entrainment into suspension is proposed which is a function of the ratio between the flow shear velocity and particle settling velocity. Observations indicate that particles totally immersed within the viscous sublayer can be entrained into suspension by the flow, which contradicts the conclusions of previous researchers. A theoretical analysis of the entrainment process within the viscous sublayer, based on force-balance considerations, is used to show that this phenomenon is related to turbulent flow events of high instantaneous values of the Reynolds stress, in agreement with previous observations. In the case of experiments with a rough bed, a hiding effect was observed, which tends to preclude the entrainment of particles finer than the roughness elements. This implies that, as the ratio between particle and roughness element sizes becomes smaller, progressively higher bed shear stresses are required to entrain particles into suspension. On the other hand, an overexposure effect was also observed, which indicates that a particle moving on a smooth bed is more prone to be entrained than the same particle moving on a bed formed by identical particles.
- Published
- 2003
37. INTEGRATING SCIENCE AND TECHNOLOGY TO SUPPORT STREAM NATURALIZATION NEAR CHICAGO, ILLINOIS
- Author
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Rebecca J. Wade, Schwartz Ja, Marcelo H. Garcia, Fabián A. Bombardelli, Edwin E. Herricks, David Wilson, José F. Rodríguez, Bruce L. Rhoads, and Melinda Daniels
- Subjects
Research program ,Vision ,Ecology ,Process (engineering) ,Context (language use) ,Watershed management ,Technical support ,Sociology ,Decision-making ,Environmental planning ,Earth-Surface Processes ,Water Science and Technology ,Social theory - Abstract
Many urban and suburban communities in the Midwest are seeking to establish sustainable, morphologically and hydraulically varied, yet dynamically stable fluvial systems that are capable of supporting healthy, biologically diverse aquatic ecosystems - a process known as stream naturalization. This paper describes an integrated research program that seeks to develop a scientific and technological framework to support two stream naturalization projects near Chicago, Illinois. The research program integrates theory and methods in fluvial geomorphology, aquatic ecology, hydraulic engineering and social theory. Both the conceptual and the practical challenges of that integration are discussed. Scientific and technical support emphasize the development of predictive tools to evaluate the performance of possible naturalization designs at scales most appropriate to community based projects. Social analysis focuses on place based evaluations of how communities formulate an environmental vision and then, through decision making, translate this vision into specific stream naturalization strategies. Integration of scientific and technical with social components occurs in the context of community based decision making as the predictive tools are employed by project scientists to help local communities translate their environmental visions into concrete environmental designs. Social analysis of this decision making process reveals how the interplay between the community's vision of what they want the watershed to become, and the scientific perspective on what the watershed can become to achieve the community's environmental goals, leads to the implementation of specific stream naturalization practices.
- Published
- 2002
38. UV-visible spectrophotometric approach to blood typing II: phenotyping of subtype A2 and weak D and whole blood analysis
- Author
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Lamar Galloway, Akihisa Nonoyama, German Leparc, Smita Narayanan, Robert Potter, and Luis H. Garcia-Rubio
- Subjects
Immunology ,Centrifugation ,Biology ,Blood typing ,ABO Blood-Group System ,Immunophenotyping ,Antigen-Antibody Reactions ,Plasma ,Random Allocation ,ABO blood group system ,medicine ,Humans ,Immunology and Allergy ,False Positive Reactions ,Single-Blind Method ,Typing ,False Negative Reactions ,Whole blood ,Rh-Hr Blood-Group System ,Chromatography ,Erythrocyte Membrane ,Hemagglutination Tests ,Hematology ,Agglutination (biology) ,Red blood cell ,medicine.anatomical_structure ,Blood Grouping and Crossmatching ,Blood Group Antigens ,Erythrocyte Count ,Indicators and Reagents ,Spectrophotometry, Ultraviolet ,Quantitative analysis (chemistry) ,Blood bank - Abstract
BACKGROUND: A recently introduced quantitative blood typing approach uses antibody-induced changes in the UV-visible spectra of blood. Changes in the blood spectra's slope, caused by RBC agglutination, are translated into a numerical agglutination index (AI). Comparing the AI value against an established threshold yields a “yes and/or no” output from which to determine the phenotype. The efficacy and flexibility of this approach with whole blood use and the ability to analyze weak D, A2, and A2B were examined. STUDY DESIGN AND METHODS: Two hundred randomly selected blood bank donor samples were coded and forward typed directly from whole blood by using the spectrophotometric analysis. Reverse grouping on plasma from each sample was carried out with a new modified procedure by using higher ratios of plasma to RBCs. Results were compared to typing by an FDA-cleared automated typing system. Twenty-seven weak D samples, 15 A2 and 12 A2B, were similarly analyzed from whole blood. PEG improved detection of weak D, A2 and A2B subtypes. RESULTS: All two hundred coded samples were accurately typed, yielding identical results to the blood bank analysis in both forward and reverse grouping. All the weak D samples and A2 and A2B samples were clearly identified, having AIs above the type threshold indicator value. CONCLUSION: Spectrophotometric blood typing successfully phenotyped ABO and D in 200 whole blood samples. Reverse grouping of plasma was equally successful. The same method can identify weak D and A2 and A2B subtypes.
- Published
- 2002
39. Ultraviolet and visible light spectrophotometric approach to blood typing: objective analysis by agglutination index
- Author
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German F. Leparc, S Narayanan, Robert Potter, S. Orton, and Luis H. Garcia-Rubio
- Subjects
Hemagglutination ,Ultraviolet Rays ,Agglutination ,Immunology ,medicine.disease_cause ,Models, Biological ,Sensitivity and Specificity ,Blood typing ,Ultraviolet visible spectroscopy ,Spectrophotometry ,medicine ,Humans ,Scattering, Radiation ,Immunology and Allergy ,Spectroscopy ,Chromatography ,medicine.diagnostic_test ,Chemistry ,Reproducibility of Results ,Hemagglutination Tests ,Hematology ,Blood Grouping and Crossmatching ,Ultraviolet ,Visible spectrum - Abstract
BACKGROUND: A new blood typing technology based on ultraviolet (UV) and visible light spectroscopy (UV/visible spectroscopy) has been developed. Blood groups and types are determined by quantifying reproducible changes in the UV and visible light spectra of blood in the presence of agglutinating antibodies. STUDY DESIGN AND METHODS: Samples of red cells in the presence and absence of agglutinating antibodies were examined by UV/visible spectroscopy. Blood groups and types were determined by comparing the optical density spectra obtained between 665 and 1000 nm. These comparisons generate numbers (agglutination index) ranging from 0 to 100, with smaller numbers corresponding to lack of agglutination and larger numbers corresponding to agglutination. RESULTS: The optical density of agglutinated blood is dramatically different from that of unagglutinated blood. The agglutination index derived from the relative slopes of the spectra is an objective indicator of agglutination strength. An agglutination index greater than 17 consistently and accurately established blood group- and type-specific agglutination. CONCLUSION: The method accurately predicted A, B, and O blood groups, and D type in over 275 samples. Scattering theory-based calculations of relative volumes of red cells before and after agglutination show a direct correlation with the agglutination index and provide the theoretical basis of the analysis. This quantitative technique is reproducible and has the potential for automation.
- Published
- 1999
40. Reversal of acute apparent diffusion coefficient abnormalities and delayed neuronal death following transient focal cerebral ischemia in rats
- Author
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Kai-Feng Liu, Sam S. Han, Julio H. Garcia, Christopher H. Sotak, Marc Fisher, Fuhai Li, and Turgut Tatlisumak
- Subjects
Pathology ,medicine.medical_specialty ,Vascular disease ,business.industry ,Central nervous system ,Ischemia ,medicine.disease ,Central nervous system disease ,medicine.anatomical_structure ,Neurology ,Cortex (anatomy) ,Occlusion ,medicine ,Effective diffusion coefficient ,Neurology (clinical) ,business ,Perfusion - Abstract
Twenty-two rats were subjected to 8, 15, 30, or 60 minutes of temporary middle cerebral artery occlusion (n = 5 per group) or sham occlusion (n = 2) in the magnetic resonance imaging unit. Diffusion-, perfusion-, and T2-weighted imaging were acquired before and during occlusion, and after reperfusion. A coregistration method was used to correlate the acute changes of the average apparent diffusion coefficient (ADCav) with the histology after 72 hours at the same topographic sites. The initially reduced ADCav values recovered completely in both the lateral caudoputamen and upper frontoparietal cortex in the 8-, 15-, and 30-minute groups, partially in the cortex, and not at all in the caudoputamen in the 60-minute group. The histology showed that the caudoputamen was either normal or had mild neuronal injury in the 8-minute group and invariably had some degree of neuronal death in the 15-, 30-, and 60-minute groups, whereas the cortex was either normal or had varying degrees of neuronal injury in all groups. No histological abnormalities were seen in the sham-operated rats. Our data suggest that acute ADCav reversal does not always predict tissue recovery from ischemic injury and that temporary focal ischemia for even 8-minute duration can cause delayed neuronal death that is more severe in the caudoputamen where the initial ADCav decline was greater than in the cortex.
- Published
- 1999
41. Hemorrhagic Transformation in Focal Cerebral Ischemia: Influence of Time to Artery Reopening and Tissue Plasminogen Activator
- Author
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Susan C. Fagan and Julio H. Garcia
- Subjects
Male ,Time Factors ,medicine.medical_treatment ,Ischemia ,Arterial Occlusive Diseases ,Tissue plasminogen activator ,Random Allocation ,Fibrinolytic Agents ,medicine ,Animals ,Pharmacology (medical) ,Rats, Wistar ,Stroke ,Saline ,Cerebral Hemorrhage ,business.industry ,Vascular disease ,T-plasminogen activator ,medicine.disease ,Thrombosis ,Rats ,Disease Models, Animal ,medicine.anatomical_structure ,Ischemic Attack, Transient ,Tissue Plasminogen Activator ,Anesthesia ,Reperfusion ,Regression Analysis ,business ,medicine.drug ,Artery - Abstract
We used an adaptation of a well-established rat model of middle cerebral artery occlusion (MCAO) that is both minimally invasive and reproducible to determine the effects of time to reperfusion and administration of tissue plasminogen activator (t-PA) on the development of hemorrhagic transformation (HT) in a rat model of acute stroke. Animals were randomized to receive either t-PA 10 mg/kg (29 rats) or an equal volume of saline (29 rats) over 20 minutes, beginning 5 minutes before reperfusion. Time to artery reopening varied between 1 and 24 hours after MCAO in both groups. At 18-24 hours after ischemia, the animals were sacrificed and their brains were preserved for analysis of HT. Logistic regression was used to determine the influence of time on HT risk and calculate the time at which 50% of animals developed HT (HT50%). At 24 hours, HT was present in 17 of 29 animals in each group and was significantly influenced by the time of artery reopening: 3 (15%) of 20 animals reperfused less than 3 hours after onset of ischemia and 32 (84%) of 38 reperfused 3 or more hours after the onset of ischemia (p
- Published
- 1999
42. Neurocysticercosis in Persons with Epilepsy in Medellin, Colombia
- Author
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Victor C. W. Tsang, Jiménez I, Jiménez Me, Jorge Sánchez, Palacio Lg, J. Noh, Margarita Giraldo, Hector H. Garcia, O. Mora, and L. Ahn
- Subjects
medicine.medical_specialty ,Pediatrics ,business.industry ,Neurocysticercosis ,Helminthiasis ,Cysticercosis ,medicine.disease ,Surgery ,Serology ,medicine.drug_formulation_ingredient ,Epilepsy ,Neurology ,parasitic diseases ,Taenia solium ,medicine ,Etiology ,Seroprevalence ,Neurology (clinical) ,business - Abstract
Summary: Purpose: A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellin, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis. Methods: All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed. Results: Prevalence of neurocys@ercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellin. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests. Conclusions: Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.
- Published
- 1998
43. Using Lagrangian particle saltation observations for bedload sediment transport modelling
- Author
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Marcelo H. Garcia and Yarko Niño
- Subjects
Condensed Matter::Soft Condensed Matter ,Stochastic modelling ,Turbulence ,Saltation (geology) ,Shear stress ,Geotechnical engineering ,Mechanics ,Particle velocity ,Sediment transport ,Magnetosphere particle motion ,Geology ,Water Science and Technology ,Bed load - Abstract
A Lagrangian model for the saltation of sand in water is proposed. Simulated saltation trajectories neglecting particle rotation and turbulence effects compare fairly well with experimental observations. The model for particle motion is coupled with a stochastic model for particle collision with the bed, such that a number of realizations of the saltation process can be simulated numerically. Model predictions of mean values and standard deviations of saltation height, length and streamwise particle velocity agree fairly well with experimental observations. Model predictions of the dynamic friction coefficient are also in good agreement with experimental observations, but they underestimate the value of 0·63 proposed by Bagnold for this coefficient. The saltation model is applied to the estimation of bedload transport rates of sand using a Bagnoldean formulation. Modelled values of the bedload transport rates overestimate those predicted by commonly used bedload formulae, which appears to be a consequence of problems in the definition of the dynamic friction coefficient. These results seem to indicate a few problems with the Bagnoldean formulation, particularly regarding the continuum assumption for the bedload layer, which would be valid only for very high particle concentrations and small particle diameters, and also regarding the evaluation of the shear stress exerted on the bed by the saltating particles. © 1998 John Wiley & Sons, Ltd.
- Published
- 1998
44. Hippocampal sclerosis: The missing link of cysticercosis epileptogenesis?
- Author
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Hector H. Garcia, Jerome Engel, Oscar H. Del Brutto, Noriko Salamon, and Dawn Eliashiv
- Subjects
Male ,Hippocampal sclerosis ,Epilepsy ,Sclerosis ,Cysticercosis ,Neurocysticercosis ,Electroencephalography ,medicine.disease ,Hippocampus ,Epileptogenesis ,Article ,Neurology ,parasitic diseases ,medicine ,Humans ,Female ,Neurology (clinical) ,Psychology ,Neuroscience - Abstract
A closed workshop was held in Atahualpa, Ecuador, with support from Universidad Espiritu Santo—Ecuador. Aims of the workshop were to gain more insights on the suggested association between neurocysticercosis (NCC), epilepsy, and hippocampal sclerosis (HS), and to design a study that will help to better characterize this association, namely, is there a causal relationship between NCC and HS, and, if so, is this association linked to chronic unprovoked seizures?
- Published
- 2014
45. Modulation of the flow structure by progressive bedforms in the Kinoshita meandering channel
- Author
-
Marcelo H. Garcia, Jorge D. Abad, Gustavo C. Buscaglia, and C. E. Frias
- Subjects
Bedform ,Turbulence ,Geography, Planning and Development ,Mechanics ,Secondary flow ,Finite element method ,Physics::Fluid Dynamics ,Free surface ,Earth and Planetary Sciences (miscellaneous) ,Compressibility ,Geotechnical engineering ,Sediment transport ,Beach morphodynamics ,Geology ,Earth-Surface Processes - Abstract
An in-house fully three-dimensional general-purpose finite element model is applied to solve the hydrodynamic structure in a periodic Kinoshita-generated meandering channel. The numerical model solves the incompressible Reynolds-averaged Navier–Stokes equations for mass and momentum, while solving the k − e equations for turbulence. The free surface is described by the rigid-lid approximation (using measured water surface data) for flat (smooth-bed) and self-formed (rough-bed) conditions. The model results are compared against experimental measurements in the ‘Kinoshita channel’, where three-dimensional flow velocities and turbulence parameters were measured. This validation was carried out for the upstream-valley meander bend orientation under smooth (flat bed) conditions. After validation, several simulations were carried out to predict the hydrodynamics in conditions where either it was not possible to perform measurements (e.g. applicability of the laboratory acoustic instruments) and to extrapolate the model to other planform configurations. For the flat smooth-bed case, a symmetric (no skewness) planform configuration was modeled and compared to the upstream-skewed case. For the self-formed rough-bed case, prediction of the hydrodynamics during the progression of bedforms was performed. It appears that the presence of bedforms on a bend has the following effects: (i) the natural secondary flow of the bend is disrupted by the presence of the bedforms, thus depending on the location of the dune, secondary flows might differ completely from the traditional orientation; (ii) an increment on both the bed and bank shear stresses is induced, having as much as 50% more fluvial erosion, and thus a potential increment on the migration rate of the bend. Implications on sediment transport and bend morphodynamics are also discussed in the paper. Copyright © 2013 John Wiley & Sons, Ltd.
- Published
- 2013
46. Studies in free radical initiation
- Author
-
Luis H. Garcia-Rubio
- Subjects
Polymers and Plastics ,Chemistry ,Organic Chemistry ,Kinetics ,Materials Chemistry ,Oxidation reduction ,Condensed Matter Physics ,Photochemistry ,Initiation - Abstract
In this paper, the consequences of the standard assumptions made in free radical initiation are explored to explain effects that could be attributed to the kinetics of initiation. Experimental results based on end-group analysis through the course of bulk and suspension polymerizations demonstrate the importance of reactions involving initiator molecules. Studies on the combined effects of mixing and initiator decomposition, and oxidation reduction systems further demonstrate the importance of an adequate description of free radical initiation mechanisms.
- Published
- 1996
47. Growth kinetics of phases in solid-state diffusion couples
- Author
-
Claudio Scherer, V. H. Garcia, and P. M. Mors
- Subjects
Atomic diffusion ,Chemical species ,Chemistry ,Differential equation ,Phase (matter) ,Nucleation ,Thermodynamics ,Physical chemistry ,Diffusion (business) ,Thin film ,Condensed Matter Physics ,Thermal diffusivity ,Electronic, Optical and Magnetic Materials - Abstract
The growth of solid phases which are produced by diffusion in bilayers or multilayers of different chemical species is studied by an approach based on an effective diffusivity. In this approach one does not assume a priori any phase layers and interfaces. A numerical procedure to obtain the solutions of the diffusion differential equation is presented and applied to a fictitious example and to a real situation. Good agreement is obtained between the calculated values and the experimental data reported in the literature for the Co/Si system. In the absence of nucleation restrictions and reaction barriers, the model is applicable to any binary diffusion couple with a given initial composition profile, for bulk or thin film configurations.
- Published
- 1995
48. RANKL expression in a case of follicular lymphoma
- Author
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Claudia Mongini, A. Ascione, C. Waldner, H. Garcia Rivello, V. Barcala, and Paula Ruybal
- Subjects
musculoskeletal diseases ,Bone disease ,biology ,business.industry ,Osteoporosis ,Follicular lymphoma ,Hematology ,General Medicine ,medicine.disease ,Bone remodeling ,Lymphoma ,Leukemia ,RANKL ,hemic and lymphatic diseases ,Cancer research ,biology.protein ,Medicine ,business ,Multiple myeloma - Abstract
The TNF-family molecule, RANKL, is a key regulator of bone remodeling and essential for the development and activation of osteoclasis. Bone involvement signals diesease activity in non-Hodgkin's lymphoma and influences the progenesis. The molecular mechanism and soluble factors involved in osteoclastic activation in haematological malignancies remain unclear except for Multiple Myeloma and Adult T-cell Leukemia. The aim of this paper is to report the first case of Follicular Lymphoma with bone involvement displaying an aberrant expression of RANKL in malignant cells. The detection of RANKL in Follicullar Lymphoma may help to prevent bone lesion in patients by determining an appropriate treatment.
- Published
- 2003
49. ChemInform Abstract: Rearrangements
- Author
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M. A. MIRANDA and H. GARCIA
- Subjects
General Medicine - Published
- 2010
50. ChemInform Abstract: 2,4,6-Triphenylpyrylium Tetrafluoroborate as an Electron-Transfer Photosensitizer
- Author
-
M. A. MIRANDA and H. GARCIA
- Subjects
General Medicine - Published
- 2010
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