36 research outputs found

    COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

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    Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≀ 18 years: 69, 48, 23; 85%), older adults (≄ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

    Reconciling ecological and economic objectives for an ecosystem approach to fisheries

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    La surpĂȘche affecte les structures et dynamiques de nombreux Ă©cosystĂšmes marins, ainsi que les services Ă©cosystĂ©miques qui en dĂ©pendent. En rĂ©ponse, scientifiques et gestionnaires plaident pour une gestion Ă©cosystĂ©mique des pĂȘches, intĂ©grant la complexitĂ© des Ă©cosystĂšmes exploitĂ©s, et fondĂ©e sur des objectifs de durabilitĂ© Ă©cologiques comme Ă©conomiques. Dans ce cadre, l'objectif de cette thĂšse est d'Ă©laborer une approche Ă©cosystĂ©mique de la gestion des pĂȘches, conciliant la prĂ©servation de la biodiversitĂ© et de la rĂ©silience des Ă©cosystĂšmes exploitĂ©s avec le maintien d'une production et de profits Ă©levĂ©s. Pour cela, nous dĂ©veloppons des modĂšles bio-Ă©conomiques de pĂȘcheries mixtes, constituĂ©es d'espĂšces indĂ©pendantes ou en interaction trophique. Nous montrons que maximiser l'ensemble des captures ou des profits d'une pĂȘcherie mixte peut menacer la biodiversitĂ© et la rĂ©silience des Ă©cosystĂšmes exploitĂ©s, mais que des instruments Ă©conomiques peuvent y remĂ©dier. L'aversion au risque en prĂ©sence d'incertitude favorise aussi une rĂ©conciliation entre diffĂ©rents enjeux de gestion. Nous dĂ©ployons ensuite des approches de gestion multi-critĂšres, afin d'identifier les meilleures stratĂ©gies en termes Ă©cologiques et Ă©conomiques. Les stratĂ©gies choisies dĂ©pendent des prĂ©fĂ©rences des gestionnaires : favoriser la production suppose d'orienter la pĂȘche vers les faibles niveaux trophiques, tandis que favoriser la biodiversitĂ© ou la rĂ©silience suppose d'orienter la pĂȘche vers des niveaux trophiques plus Ă©levĂ©s. Nous suggĂ©rons ainsi qu'une diversification du profil de pĂȘche permettrait de concilier enjeux Ă©cologiques et Ă©conomiques pour une gestion Ă©cosystĂ©mique et durable des pĂȘches.Overfishing affects the structures and dynamics of many marine ecosystems, as well as the associated ecosystem services. To tackle this issue, many scientists and managers are calling for an ecosystem-based fisheries management, integrating the complexity of harvested ecosystems, and based on ecological and economic sustainability objectives. In that perspective, our aim is to build an ecosystem approach to fisheries management, reconciling biodiversity and resilience preservation with the maintenance of high yields and profits. To this aim, we develop bio-economic models of mixed fisheries, composed of species that are either independent or in trophic interactions. We show that maximizing the aggregate catches or profits of a mixed fishery can threaten the biodiversity and resilience of harvested ecosystems, but that economic instruments can address these issues. In uncertain systems, risk aversion also helps reconciling constrasting management goals. We then apply multi-objective management approaches to identify the best strategies from an ecological and economic point of view. Chosen strategies depend on managers' preferences: favoring production implies to focus harvest on small trophic levels, while favoring biodiversity or resilience implies to focus on higher trophic levels. We therefore suggest that diversified fishing patterns could allow reconciling ecological with economic objectives, in order to achieve a sustainable ecosystem approach to fisheries management

    Concilier enjeux Ă©cologiques et Ă©conomiques pour une gestion Ă©cosystĂ©mique des pĂȘches

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    Overfishing affects the structures and dynamics of many marine ecosystems, as well as the associated ecosystem services. To tackle this issue, many scientists and managers are calling for an ecosystem-based fisheries management, integrating the complexity of harvested ecosystems, and based on ecological and economic sustainability objectives. In that perspective, our aim is to build an ecosystem approach to fisheries management, reconciling biodiversity and resilience preservation with the maintenance of high yields and profits. To this aim, we develop bio-economic models of mixed fisheries, composed of species that are either independent or in trophic interactions. We show that maximizing the aggregate catches or profits of a mixed fishery can threaten the biodiversity and resilience of harvested ecosystems, but that economic instruments can address these issues. In uncertain systems, risk aversion also helps reconciling constrasting management goals. We then apply multi-objective management approaches to identify the best strategies from an ecological and economic point of view. Chosen strategies depend on managers' preferences: favoring production implies to focus harvest on small trophic levels, while favoring biodiversity or resilience implies to focus on higher trophic levels. We therefore suggest that diversified fishing patterns could allow reconciling ecological with economic objectives, in order to achieve a sustainable ecosystem approach to fisheries management.La surpĂȘche affecte les structures et dynamiques de nombreux Ă©cosystĂšmes marins, ainsi que les services Ă©cosystĂ©miques qui en dĂ©pendent. En rĂ©ponse, scientifiques et gestionnaires plaident pour une gestion Ă©cosystĂ©mique des pĂȘches, intĂ©grant la complexitĂ© des Ă©cosystĂšmes exploitĂ©s, et fondĂ©e sur des objectifs de durabilitĂ© Ă©cologiques comme Ă©conomiques. Dans ce cadre, l'objectif de cette thĂšse est d'Ă©laborer une approche Ă©cosystĂ©mique de la gestion des pĂȘches, conciliant la prĂ©servation de la biodiversitĂ© et de la rĂ©silience des Ă©cosystĂšmes exploitĂ©s avec le maintien d'une production et de profits Ă©levĂ©s. Pour cela, nous dĂ©veloppons des modĂšles bio-Ă©conomiques de pĂȘcheries mixtes, constituĂ©es d'espĂšces indĂ©pendantes ou en interaction trophique. Nous montrons que maximiser l'ensemble des captures ou des profits d'une pĂȘcherie mixte peut menacer la biodiversitĂ© et la rĂ©silience des Ă©cosystĂšmes exploitĂ©s, mais que des instruments Ă©conomiques peuvent y remĂ©dier. L'aversion au risque en prĂ©sence d'incertitude favorise aussi une rĂ©conciliation entre diffĂ©rents enjeux de gestion. Nous dĂ©ployons ensuite des approches de gestion multi-critĂšres, afin d'identifier les meilleures stratĂ©gies en termes Ă©cologiques et Ă©conomiques. Les stratĂ©gies choisies dĂ©pendent des prĂ©fĂ©rences des gestionnaires : favoriser la production suppose d'orienter la pĂȘche vers les faibles niveaux trophiques, tandis que favoriser la biodiversitĂ© ou la rĂ©silience suppose d'orienter la pĂȘche vers des niveaux trophiques plus Ă©levĂ©s. Nous suggĂ©rons ainsi qu'une diversification du profil de pĂȘche permettrait de concilier enjeux Ă©cologiques et Ă©conomiques pour une gestion Ă©cosystĂ©mique et durable des pĂȘches

    Balancing yield with resilience and conservation objectives in harvested predator-prey communities

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    International audienceThe global overexploitation of fish stocks is endangering many marine food webs. Scientists and managers now call for an ecosystem-based fisheries management, able to take into account the complexity of marine ecosystems and the multiple ecosystem services they provide. By contrast, many fishery management plans only focus on maximizing the productivity of harvested stocks. Such practices are suggested to affect other ecosystem services, altering the integrity and resilience of natural communities. Here we show that while yield-maximizing policies can allow for coexistence and resilience in predator–prey communities, they are not optimal in a multi-objective context. We find that although total prey and predator maximum yields are higher with a prey-oriented harvest, focusing on the predator improves species coexistence. Also, moderate harvesting of the predator can enhance resilience. Furthermore, increasing maximum yields by changing catchabilities improves resilience in predator-oriented systems, but reduces it in prey-oriented systems. In a multi-objective context, optimal harvesting strategies involve a general tradeoff between yield and resilience. Resilience-maximizing strategies are however compatible with quite high yields, and should often be favored. Our results further suggest that balancing harvest between trophic levels is often best at maintaining simultaneously species coexistence, resilience and yield

    Etude de l'énucléation chez les carnivores domestiques

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    L'auteur aborde tout d'abord dans cette Ă©tude les donnĂ©es bibliographiques concernant l'Ă©nuclĂ©ation chez les carnivores domestiques : anatomie de l'oeil, indications et contre indications de l'Ă©nuclĂ©ation, manuel opĂ©ratoire, incidents, accidents et complications. Une Ă©tude de 73 cas cliniques permet de relever les principales indications alors classĂ©es en 4 groupes : les suites de traumatisme, les suites chirurgicales, les suites mĂ©dicales et les tumeurs ; ainsi que la technique chirurgicale employĂ©e et l'Ă©pidĂ©miologie de la population comprenant la race, le sexe et l'Ăąge de l'animal. Il s'agit de chiens ĂągĂ©s en moyenne de 8 ans et 10 mois. Les indications les plus frĂ©quentes sont les tumeurs et les suites mĂ©dicales (36 %), comprenant essentiellement des cas de glaucome. Elles nĂ©cessitent dans la plupart des cas une Ă©nuclĂ©ation et touchent des chiens de petite taille sauf pour le groupe des tumeurs oĂč une exentĂ©ration est rĂ©alisĂ©e dans 72 % des cas, chez des chiens de chasse ou d'utilitĂ©. Aucune complication ne s'est produite Ă  la suite de ces interventions.NANTES-Ecole Nat.VĂ©tĂ©rinaire (441092302) / SudocSudocFranceF

    Oscillation : bioadĂ©quation et bien-ĂȘtre sont-ils l'avenir d'un progrĂšs durable pour nos enfants ?

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    Dans les dĂ©cennies Ă  venir, l'adaptation au changement climatique est une question vitale pour la perpĂ©tuation des espĂšces vĂ©gĂ©tales et animales, dont l’espĂšce humaine. Alors vers quel type d'adaptation souhaitons-nous aller ? L’usage du mot « adaptation » est aujourd'hui confus. Les notions « d’adaptation », de dynamiques de dĂ©veloppement des espĂšces, dont celle de l’humain et de leurs « relations de dĂ©pendances » semblent mal comprises par les leaders d’opinion, les dĂ©cideurs publics et les profanes. La question de l’adaptation au rĂ©chauffement climatique est-elle bien posĂ©e en termes de bien-ĂȘtre d’humanitĂ© et de progrĂšs sociĂ©tal ? Les auteurs s’interrogent sur la hauteur de vue que l'humain doit atteindre pour une meilleure vision de son devenir dans et sur la nature, mais aussi de son Ă©panouissement relationnel et comportemental avec les autres espĂšces pour un mieux-ĂȘtre comme source de bien-ĂȘtre et indicateur de progrĂšs. Trois perspectives diffĂ©rentes de la conception commune de l'adaptation dans la sociĂ©tĂ© occidentale sont proposĂ©es : la bioadĂ©quation, la compensation et l'adaptation. Ces trois sens contribuent Ă  replacer l'humain comme ĂȘtre biologique et espĂšce animale vivant en relation avec d’autres espĂšces domestiques et sauvages. Aussi dans le contexte de notre dynamique de dĂ©veloppement en zones urbaines et pĂ©riurbaines, ce discernement participe Ă  ouvrir le dĂ©bat sur les aptitudes rĂ©elles de rĂ©ponses des espĂšces face aux alĂ©as du changement climatique.In the coming decades, adaptation to climate change is a critical issue for plant and animal species, especially humans. However, what kind of adaptation we want to go through? Today, the use of the word "adaptation" is confused. The concepts of "adaptation", dynamics development of species, in particular the development of man, and their "dependency relations" seem misunderstood by opinion leaders, policy makers and laymen. Is this adaptation well defined for the well-being of mankind and the progress of societies? In the context of this work, the authors questioned the height of view that humans must achieve to get a better vision of their fate and nature, relational and behavioral development of individuals being a source of well-being and progress indicator. Three different perspectives of the common conception of adaptation in our Western society are addressed: bioadequation, compensation and adaptation. These three perspectives will help to replace the human being as a biological being and animal species living in relationship with other species. So in the context of our dynamic development in urban and suburban areas, this discernment involved in opening the debate on the real abilities of species responses to climate change hazards

    Optimal Harvesting Policies Threaten Biodiversity in Mixed Fisheries

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    s marine ecosystems are under pressure worldwide, many scientists and stakeholders advocate the use of ecosystem-based approaches for fishery management. In particular, management policies are expected to account for the multispecies nature of fisheries. However, numerous fisheries management plans remain based on single-species concepts, such as maximum sustainable yield (MSY) and maximum economic yield (MEY), that respectively aim at maximizing catches or profits of single species or stocks. In this study, we assess the bioeconomic sustainability of multispecies MSY and MEY in a mixed fishery, characterized by technical interactions and therefore joint production. First, we analytically show how multispecies MSY and MEY can induce overharvesting and extinction of species with low productivity and low value. Second, we identify and discuss incentives on effort costs and landing prices, as well as technical regulations, that could promote biodiversity conservation and more globally sustainability. Finally, a numerical example based on the coastal fishery in French Guiana illustrates the analytical findings

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