34 research outputs found

    Animal-borne telemetry: An integral component of the ocean observing toolkit

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    Animal telemetry is a powerful tool for observing marine animals and the physical environments that they inhabit, from coastal and continental shelf ecosystems to polar seas and open oceans. Satellite-linked biologgers and networks of acoustic receivers allow animals to be reliably monitored over scales of tens of meters to thousands of kilometers, giving insight into their habitat use, home range size, the phenology of migratory patterns and the biotic and abiotic factors that drive their distributions. Furthermore, physical environmental variables can be collected using animals as autonomous sampling platforms, increasing spatial and temporal coverage of global oceanographic observation systems. The use of animal telemetry, therefore, has the capacity to provide measures from a suite of essential ocean variables (EOVs) for improved monitoring of Earth's oceans. Here we outline the design features of animal telemetry systems, describe current applications and their benefits and challenges, and discuss future directions. We describe new analytical techniques that improve our ability to not only quantify animal movements but to also provide a powerful framework for comparative studies across taxa. We discuss the application of animal telemetry and its capacity to collect biotic and abiotic data, how the data collected can be incorporated into ocean observing systems, and the role these data can play in improved ocean management

    Carbone des sols en Afrique

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    Les sols sont une ressource essentielle Ă  prĂ©server pour la production d’aliments, de fibres, de biomasse, pour la filtration de l’eau, la prĂ©servation de la biodiversitĂ© et le stockage du carbone. En tant que rĂ©servoirs de carbone, les sols sont par ailleurs appelĂ©s Ă  jouer un rĂŽle primordial dans la lutte contre l’augmentation de la concentration de gaz Ă  effet de serre. Ils sont ainsi au centre des objectifs de dĂ©veloppement durable (ODD) des Nations unies, notamment les ODD 2 « Faim zĂ©ro », 13 « Lutte contre le changement climatique », 15 « Vie terrestre », 12 « Consommation et production responsables » ou encore 1 « Pas de pauvretĂ© ». Cet ouvrage prĂ©sente un Ă©tat des lieux des sols africains dans toute leur diversitĂ©, mais au-delĂ , il documente les capacitĂ©s de stockage de carbone selon les types de sols et leurs usages en Afrique. Il propose Ă©galement des recommandations autour de l’acquisition et de l’interprĂ©tation des donnĂ©es, ainsi que des options pour prĂ©server, voire augmenter les stocks de carbone dans les sols. Tous les chercheurs et acteurs du dĂ©veloppement impliquĂ©s dans les recherches sur le rĂŽle du carbone des sols sont concernĂ©s par cette synthĂšse collective. Fruit d’une collaboration entre chercheurs africains et europĂ©ens, ce livre insiste sur la nĂ©cessitĂ© de prendre en compte la grande variĂ©tĂ© des contextes agricoles et forestiers africains pour amĂ©liorer nos connaissances sur les capacitĂ©s de stockage de carbone des sols et lutter contre le changement climatique

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Étude multi-Ă©chelle des variations structurales, gĂ©ochimiques et des propriĂ©tĂ©s magnĂ©tiques des coulĂ©es basaltiques prismĂ©es (exemple de la coulĂ©e de La Palisse (ArdĂšche) et de Saint-Arcons-d'Allier (Haute-Loire))

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    Des structures prismĂ©es sont frĂ©quemment observĂ©es dans les coulĂ©es de lave comme la ChaussĂ©e des GĂ©ants (Irlande). Plusieurs thĂ©ories existent pour expliquer ces formations, dont la plus rĂ©pandue est celle de la contraction thermique. Or cette thĂ©orie permet difficilement de comprendre certaines observations de terrain comme la sĂ©paration frĂ©quente des coulĂ©es en plusieurs niveaux. Afin de mieux comprendre la structuration au sein des coulĂ©es basaltiques, nous avons procĂ©dĂ© Ă  une Ă©tude pluridisciplinaire basĂ©e sur les propriĂ©tĂ©s magnĂ©tiques, les variations structurales et gĂ©ochimiques de deux coulĂ©es prismĂ©es du Massif Central (La Palisse, ArdĂšche et Saint-Arcons-d Allier, Haute-Loire). Notre approche permet de montrer que les fabriques cristallographiques et magnĂ©tiques sont gouvernĂ©es par l Ă©coulement de la lave. L orientation du plagioclase contrĂŽle la distribution des titanomagnĂ©tites Ă  l origine des fabriques magnĂ©tiques. Notre Ă©tude montre Ă©galement que l utilisation de l ASM est un outil fiable pour dĂ©terminer l orientation de l Ă©coulement Ă  condition d ĂȘtre contrĂŽlĂ©e par des mesures de fabriques cristallographiques. Les mesures de la quantitĂ© d eau et les analyses isotopiques (H et O) montrent que l effet de l altĂ©ration mĂ©tĂ©orique est faible et que l eau contenue dans la roche est essentiellement de l'eau de constitution. De plus, Ă  l Ă©chelle du prisme, des variations de deuxiĂšme ordre sont observĂ©es comme celle des paramĂštres d hystĂ©rĂ©sis qui indique des tailles de grains de titanomagnĂ©tites plus importantes vers le centre. Ces variations au sein du prisme semblent difficilement compatibles avec une structuration des coulĂ©es par la simple contraction thermique.Columnar jointing is frequently observed in lava flows, as in the Giant Causeway (Ireland). The most common theory explaining the formation of prisms is by the thermal contraction. However, this theory hardly explains some field observations such as the frequent existence of three parts within the lavas flows, from the base to the top. To complete our understanding of the structuring lava flows, we carried out a multidisciplinary study based on the magnetic properties, structural and geochemical characterization of two basaltic flows from the French Massif Central (La Palisse, ArdĂšche and Saint-Arcons-d'Allier, Haute-Loire). Our approach shows that crystallographic and magnetic fabrics are governed by the flow. The distribution of titanomagnetite grains carrying the magnetic fabrics is mainly controlled by the plagioclase orientation. Our study also shows that the use of the AMS to determine the flow direction is a reliable tool, provided punctual control by measurements of crystallographic fabrics are performed. Measurements of the water content and isotopic analyses (H and O) show a limited weathering effect in the studied areas: rock water is mostly primary water in equilibrium with the magma. Moreover, second order changes are noted across the prism section such as hysteresis parameters associated to grain size variation of titanomagnetite (larger grains in the center). The variations of magnetic properties across the prism section suggest a gradient of the crystallization rate from the center to the edge of the prism, which seems difficult to reconcile with the structuring of the flow by thermal contraction only.ST ETIENNE-ENS des Mines (422182304) / SudocSudocFranceF

    Formes graves de grippe en Réanimation (une étude descriptive comparative de la grippe saisonniÚre et de la grippe pandémique A(H1N1))

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    Il s'agit d'une Ă©tude descriptive rĂ©trospective, comparant deux groupes de 17 et 18 patients, atteints respectivement de grippe A (H1N1) et de grippe saisonniĂšre, et hospitalisĂ©s en rĂ©animation entre 1993 et 2011. Le diagnostic de grippe devait ĂȘtre documentĂ©, sur prĂ©lĂšvements respiratoires, par RT-PCR, immunofluorescence, culture cellulaire et/ou sĂ©rologie. On relevait donnĂ©es dĂ©mographiques, comorbiditĂ©s, statut vaccinal, date des 1ers symptĂŽmes, de l'hospitalisation, de l'admission en rĂ©animation et du diagnostic, IGS 2, survenue de dĂ©faillances, dont le SDRA, surinfections bactĂ©riennes, traitements reçus, et devenir du patient. Les patients H1N1 Ă©taient plus jeunes (41 ans vs 56, p=0.04) et avait plus tendance Ă  ĂȘtre obĂšse ( 41% vs 6%, p=0.03) et fumeurs (65% vs 287%, p=0.01). Les symptĂŽmes grippaux et les complications n'Ă©taient pas diffĂ©rentes pendant le sĂ©jour en rĂ©animation. Le dĂ©lai diagnostique Ă©tait plus court en pĂ©riode pandĂ©mique (<24h vs 4 jours, p=0,01). L'Oseltamivir Ă©tait plus utilisĂ© en situation pandĂ©mique (88% vs 11%, p=0.01). La grippe A (H1N1) a touchĂ© des patients plus jeunes, plus frĂ©quemment obĂšses et fumeurs. MĂȘme si la grippe pandĂ©mique Ă©tait diagnostiquĂ©e plus rapidement, et traitĂ©e plus frĂ©quemment par l'Oseltamivir, le devenir des patients n'Ă©tait pas diffĂ©rent.RENNES1-BU SantĂ© (352382103) / SudocSudocFranceF

    Genetic status of the endangered plant species Gladiolus palustris in the western part of its distribution area

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    International audienceMany endangered plant species suffer from the effects of ongoing fragmentation of their populations leading to a loss of genetic diversity through genetic drift. In addition, populations of rare plants may also be affected by hybridization with other plant species. We studied the genetic population structure of populations of the endangered Gladiolus palustris in the western limit of its distribution area using AFLP markers. In addition, we clarified the taxonomic status of populations where hybridization with the closely related G. imbricatus was suspected based on morphology by sequencing the ITS region of the nuclear ribosomal DNA as well as two regions of the chloroplast DNA. Our analysis of the genetic population structure of G. palustris revealed a strong differentiation among geographical regions, which was much higher than the differentiation among populations within regions. Most populations retained a considerable amount of genetic variation. To counteract the future loss of genetic diversity through drift, we recommend using the largest populations per region as seed source to increase genetic diversity in genetic depauperate populations of the same region. Our genetic analyses indicated that some French populations of G. palustris are of hybrid origin. These hybridization events are likely to be ancient as these populations are very isolated and some parent taxa went regionally extinct. As these hybrid populations may elucidate post-glacial distribution patterns of related Gladiolus taxa, we advocate that they deserve the same conservation efforts as purebred ones
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