Cartographie et évaluation multi-échelle de l'étalement urbain à l'aide d'images Spot XS : Exemple du Mans (Ouest-France)

Les recherches sur l'étalement urbain posent la question de la cartographie, de l'évaluation et du suivi spatio-temporel des villes. Elles interpellent la télédétection car celle-ci fournit en continu des images qui permettent de caractériser les territoires et leur évolution. Nous avons utilisé deux images satellites Spot XS de 1993 et de 2006 pour cartographier les modes d'occupation du sol et pour évaluer l'emprise et l'évolution du bâti dans le contexte géographique régional de l'Ouest de la France à travers l'exemple du Mans. Des classifications supervisées ont été appliquées à ces images suivant une approche multi-échelle qui distingue trois niveaux scalaires : l'agglomération urbaine, la communauté urbaine et la ville intra muros. Les résultats indiquent que l'étalement urbain décroît lorsqu'on passe du niveau de l'agglomération au niveau de la ville. De 1993 à 2006, les surfaces bâties ont augmenté au total de 49% (+2 439 ha) dans l'agglomération urbaine, de 22% (+1 168 ha) dans la communauté urbaine, de 6% (+233 ha) dans la ville du Mans intra muros. Ces résultats montrent qu'au niveau de la ville, le phénomène d'étalement urbain est caractérisé par la densification du bâti dans le peu d'espaces non bâtis encore disponibles, tandis qu'aux niveaux de l'agglomération et de la communauté urbaine, l'étalement urbain se déroule par de nouvelles constructions et par le mitage des espaces constructibles situés dans les communes périphériques de la ville du Mans

Receptor-Mediated Transcytosis of Leptin through Human Intestinal Cells In Vitro

Gastric Leptin is absorbed by duodenal enterocytes and released on the basolateral side towards the bloodstream. We investigated in vitro some of the mechanisms of this transport. Caco-2/15 cells internalize leptin from the apical medium and release it through transcytosis in the basal medium in a time- temperature-dependent and saturable fashion. Leptin receptors are revealed on the apical brush-border membrane of the Caco-2 cells. RNA-mediated silencing of the receptor led to decreases in the uptake and basolateral release. Leptin in the basal medium was found bound to the soluble form of its receptor. An inhibitor of clathrin-dependent endocytosis (chlorpromazine) decreased leptin uptake. Confocal immunocytochemistry and the use of brefeldin A and okadaic acid revealed the passage of leptin through the Golgi apparatus. We propose that leptin transcytosis by intestinal cells depends on its receptor, on clathrin-coated vesicles and transits through the Golgi apparatus

Detection Limits for Natural Circular Dichroism of Chiral Complexes in the X-ray Range

Whereas both Magnetic Circular Dichroism and Faraday Rotation studies have been successfully carried out at the K-, L- and M- absorption edges of metal atoms in ferromagnetic systems, Natural optical activity of chiral complexes has not yet been detected quite unambiguously in the X-ray range. We review a number of theoretical arguments which confirm that the optical asymmetry factor g(sigma) should be very small in the X-ray range for unoriented powdered samples, especially at the K-absorption edges. This stimulating challenge prompted us to start an intensive programme of measurements aimed at detecting natural circular dichroism in both the soft and ''firm'' X-ray ranges. Although some of our experiments look consistent with the presence of the expected effect, our conclusions cannot be taken yet as definitive due to the presence of a weak residual signal which, unfortunately, could not be eliminated

Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

The bii4africa dataset of faunal and floral population intactness estimates across Africa’s major land uses

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species’ population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate ‘intactness scores’: the remaining proportion of an ‘intact’ reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region’s major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/ taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Intérêt du dosage de l'activité de la protéase ADAMTS 13 dans les microangiopathies thrombotiques de l'adulte

REIMS-BU Santé (514542104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Cartographie et évaluation multi-échelle de l'étalement urbain à l'aide d'images Spot XS : Exemple du Mans (Ouest-France)

Les recherches sur l'étalement urbain posent la question de la cartographie, de l'évaluation et du suivi spatio-temporel des villes. Elles interpellent la télédétection car celle-ci fournit en continu des images qui permettent de caractériser les territoires et leur évolution. Nous avons utilisé deux images satellites Spot XS de 1993 et de 2006 pour cartographier les modes d'occupation du sol et pour évaluer l'emprise et l'évolution du bâti dans le contexte géographique régional de l'Ouest de la France à travers l'exemple du Mans. Des classifications supervisées ont été appliquées à ces images suivant une approche multi-échelle qui distingue trois niveaux scalaires : l'agglomération urbaine, la communauté urbaine et la ville intra muros. Les résultats indiquent que l'étalement urbain décroît lorsqu'on passe du niveau de l'agglomération au niveau de la ville. De 1993 à 2006, les surfaces bâties ont augmenté au total de 49% (+2 439 ha) dans l'agglomération urbaine, de 22% (+1 168 ha) dans la communauté urbaine, de 6% (+233 ha) dans la ville du Mans intra muros. Ces résultats montrent qu'au niveau de la ville, le phénomène d'étalement urbain est caractérisé par la densification du bâti dans le peu d'espaces non bâtis encore disponibles, tandis qu'aux niveaux de l'agglomération et de la communauté urbaine, l'étalement urbain se déroule par de nouvelles constructions et par le mitage des espaces constructibles situés dans les communes périphériques de la ville du Mans