65 research outputs found

    Up-Date on the Behaviour and Status of the Critically Endangered Onager, \u3ci\u3eEquus hemionus onager\u3c/i\u3e, from Iran

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    The onager, Equus hemionus onager, an Asiatic wild ass endemic to Iran, is categorized as Critically Endangered on the IUCN Red List. Its biology and conservation requirements are poorly documented. We report some observations made in 1997 and 2000 on the behavior and ecology of the two remaining populations, located in the Touran Protected Area and the Bahram-e-Goor Reserve. Recent population counts by the Department of Environment of Iran (471 in the Protected Area, and 96 in the Reserve) are markedly lower than the count of 600-770 made in the 1970s in the Touran Protected Area. We observed social interactions between stallions and mares outside the breeding season which contrast to the known social structure of this Persian subspecies. Poaching, competitions with domestic animals, removal of shrubs for domestic use, and land conversion have been identified as the main threats to the two remaining onager populations. In addition, geographical isolation could cause the loss of genetic variability in these two relatively small populations, and also makes them more susceptible to the potential effects of stochastic events such as drought or disease. Public awareness, protection, and scientific studies in Iran must be urgently supported by both national and international organizations in order to prevent the extinction of these two apparently dwindling populations of onager

    Applying advanced data analytics and machine learning to enhance the safety control of dams

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    The protection of critical engineering infrastructures is vital to today’s so- ciety, not only to ensure the maintenance of their services (e.g., water supply, energy production, transport), but also to avoid large-scale disasters. Therefore, technical and financial efforts are being continuously made to improve the safety control of large civil engineering structures like dams, bridges and nuclear facilities. This con- trol is based on the measurement of physical quantities that characterize the struc- tural behavior, such as displacements, strains and stresses. The analysis of monitor- ing data and its evaluation against physical and mathematical models is the strongest tool to assess the safety of the structural behavior. Commonly, dam specialists use multiple linear regression models to analyze the dam response, which is a well- known approach among dam engineers since the 1950s decade. Nowadays, the data acquisition paradigm is changing from a manual process, where measurements were taken with low frequency (e.g., on a weekly basis), to a fully automated process that allows much higher frequencies. This new paradigm escalates the potential of data analytics on top of monitoring data, but, on the other hand, increases data quality issues related to anomalies in the acquisition process. This chapter presents the full data lifecycle in the safety control of large-scale civil engineering infrastructures (focused on dams), from the data acquisition process, data processing and storage, data quality and outlier detection, and data analysis. A strong focus is made on the use of machine learning techniques for data analysis, where the common multiple linear regression analysis is compared with deep learning strategies, namely recur- rent neural networks. Demonstration scenarios are presented based on data obtained from monitoring systems of concrete dams under operation in Portugal.info:eu-repo/semantics/acceptedVersio

    High-resolution 3D analysis of mouse small-intestinal stroma.

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    Here we detail a protocol for whole-mount immunostaining of mouse small-intestinal villi that can be used to generate high-resolution 3D images of all gut cell types, including blood and lymphatic vessel cells, neurons, smooth muscle cells, fibroblasts and immune cells. The procedure describes perfusion, fixation, dissection, immunostaining, mounting, clearing, confocal imaging and quantification, using intestinal vasculature as an example. As intestinal epithelial cells prevent visualization with some antibodies, we also provide an optional protocol to remove these cells before fixation. In contrast to alternative current techniques, our protocol enables the entire villus to be visualized with increased spatial resolution of cell location, morphology and cell-cell interactions, thus allowing for easy quantification of phenotypes. The technique, which takes 7 d from mouse dissection to microscopic examination, will be useful for researchers who are interested in most aspects of intestinal biology, including mucosal immunology, infection, nutrition, cancer biology and intestinal microbiota

    Helicobacter pylori Infection of Gastrointestinal Epithelial Cells in vitro Induces Mesenchymal Stem Cell Migration through an NF-κB-Dependent Pathway

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    The role of bone marrow-derived mesenchymal stem cells (MSC) in the physiology of the gastrointestinal tract epithelium is currently not well established. These cells can be recruited in response to inflammation due to epithelial damage, home, and participate in tissue repair. In addition, in the case of tissue repair failure, these cells could transform and be at the origin of carcinomas. However, the chemoattractant molecules responsible for MSC recruitment and migration in response to epithelial damage, and particularly to Helicobacter pylori infection, remain unknown although the role of some chemokines has been suggested. This work aimed to get insight into the mechanisms of mouse MSC migration during in vitro infection of mouse gastrointestinal epithelial cells by H. pylori. Using a cell culture insert system, we showed that infection of gastrointestinal epithelial cells by different H. pylori strains is able to stimulate the migration of MSC. This mechanism involves the secretion by infected epithelial cells of multiple cytokines, with a major role of TNFα, mainly via a Nuclear Factor-kappa B-dependent pathway. This study provides the first evidence of the role of H. pylori infection in MSC migration and paves the way to a better understanding of the role of bone marrow-derived stem cells in gastric pathophysiology and carcinogenesis

    L-Plastin nanobodies perturb matrix degradation, podosome formation, stability and lifetime in THP-1 macrophages

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    Podosomes are cellular structures acting as degradation ‘hot-spots’ in monocytic cells. They appear as dot-like structures at the ventral cell surface, enriched in F-actin and actin regulators, including gelsolin and L-plastin. Gelsolin is an ubiquitous severing and capping protein, whereas L-plastin is a leukocyte-specific actin bundling protein. The presence of the capping protein CapG in podosomes has not yet been investigated. We used an innovative approach to investigate the role of these proteins in macrophage podosomes by means of nanobodies or Camelid single domain antibodies. Nanobodies directed against distinct domains of gelsolin, L-plastin or CapG were stably expressed in macrophage-like THP-1 cells. CapG was not enriched in podosomes. Gelsolin nanobodies had no effect on podosome formation or function but proved very effective in tracing distinct gelsolin populations. One gelsolin nanobody specifically targets actin-bound gelsolin and was effectively enriched in podosomes. A gelsolin nanobody that blocks gelsolin-G-actin interaction was not enriched in podosomes demonstrating that the calcium-activated and actin-bound conformation of gelsolin is a constituent of podosomes. THP-1 cells expressing inhibitory L-plastin nanobodies were hampered in their ability to form stable podosomes. Nanobodies did not perturb Ser5 phosphorylation of L-plastin although phosphorylated L-plastin was highly enriched in podosomes. Furthermore, nanobody-induced inhibition of L-plastin function gave rise to an irregular and unstable actin turnover of podosomes, resulting in diminished degradation of the underlying matrix. Altogether these results indicate that L-plastin is indispensable for podosome formation and function in macrophages

    Cardiac lymphatics in health and disease

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    The lymphatic vasculature, which accompanies the blood vasculature in most organs, is indispensable in the maintenance of tissue fluid homeostasis, immune cell trafficking, and nutritional lipid uptake and transport, as well as in reverse cholesterol transport. In this Review, we discuss the physiological role of the lymphatic system in the heart in the maintenance of cardiac health and describe alterations in lymphatic structure and function that occur in cardiovascular pathology, including atherosclerosis and myocardial infarction. We also briefly discuss the role that immune cells might have in the regulation of lymphatic growth (lymphangiogenesis) and function. Finally, we provide examples of how the cardiac lymphatics can be targeted therapeutically to restore lymphatic drainage in the heart to limit myocardial oedema and chronic inflammation.Peer reviewe

    Up-Date on the Behaviour and Status of the Critically Endangered Onager, \u3ci\u3eEquus hemionus onager\u3c/i\u3e, from Iran

    Get PDF
    The onager, Equus hemionus onager, an Asiatic wild ass endemic to Iran, is categorized as Critically Endangered on the IUCN Red List. Its biology and conservation requirements are poorly documented. We report some observations made in 1997 and 2000 on the behavior and ecology of the two remaining populations, located in the Touran Protected Area and the Bahram-e-Goor Reserve. Recent population counts by the Department of Environment of Iran (471 in the Protected Area, and 96 in the Reserve) are markedly lower than the count of 600-770 made in the 1970s in the Touran Protected Area. We observed social interactions between stallions and mares outside the breeding season which contrast to the known social structure of this Persian subspecies. Poaching, competitions with domestic animals, removal of shrubs for domestic use, and land conversion have been identified as the main threats to the two remaining onager populations. In addition, geographical isolation could cause the loss of genetic variability in these two relatively small populations, and also makes them more susceptible to the potential effects of stochastic events such as drought or disease. Public awareness, protection, and scientific studies in Iran must be urgently supported by both national and international organizations in order to prevent the extinction of these two apparently dwindling populations of onager

    SPERA : le Service de Préparation à l'Examen RadioAmateur. Une expérience de e-formation au radioamateurisme et à l'électronique

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    Cet article présente le service en ligne SPERA de préparation à l'examen radioamateur. Ce service web interactif proposé par le radio club F6KQH de l'ENSEIRB (École Nationale Supérieure d'Électronique d'Informatique et de Radiocommunications de Bordeaux) permet à tout futur radioamateur ou passionné d'électronique de se préparer chez lui à la licence radioamateur délivrée par l'Autorité de Régulation des Télécommunications (ART) ou plus simplement à l'électronique
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