83 research outputs found

    Characteristics of meiofauna in extreme marine ecosystems: a review

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    Extreme marine environments cover more than 50% of the Earth’s surface and offer many opportunities for investigating the biological responses and adaptations of organisms to stressful life conditions. Extreme marine environments are sometimes associated with ephemeral and unstable ecosystems, but can host abundant, often endemic and well-adapted meiofaunal species. In this review, we present an integrated view of the biodiversity, ecology and physiological responses of marine meiofauna inhabiting several extreme marine environments (mangroves, submarine caves, Polar ecosystems, hypersaline areas, hypoxic/anoxic environments, hydrothermal vents, cold seeps, carcasses/sunken woods, deep-sea canyons, deep hypersaline anoxic basins [DHABs] and hadal zones). Foraminiferans, nematodes and copepods are abundant in almost all of these habitats and are dominant in deep-sea ecosystems. The presence and dominance of some other taxa that are normally less common may be typical of certain extreme conditions. Kinorhynchs are particularly well adapted to cold seeps and other environments that experience drastic changes in salinity, rotifers are well represented in polar ecosystems and loriciferans seem to be the only metazoan able to survive multiple stressors in DHABs. As well as natural processes, human activities may generate stressful conditions, including deoxygenation, acidification and rises in temperature. The behaviour and physiology of different meiofaunal taxa, such as some foraminiferans, nematode and copepod species, can provide vital information on how organisms may respond to these challenges and can provide a warning signal of anthropogenic impacts. From an evolutionary perspective, the discovery of new meiofauna taxa from extreme environments very often sheds light on phylogenetic relationships, while understanding how meiofaunal organisms are able to survive or even flourish in these conditions can explain evolutionary pathways. Finally, there are multiple potential economic benefits to be gained from ecological, biological, physiological and evolutionary studies of meiofauna in extreme environments. Despite all the advantages offered by meiofauna studies from extreme environments, there is still an urgent need to foster meiofauna research in terms of composition, ecology, biology and physiology focusing on extreme environments

    Le site stratifié du Bois Clair à Montguyon (Charente-Maritime, France) : récurrences paléolithiques, brièveté des occupations et aires de débitage spécialisées

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    Le site du Bois Clair constitue un nouveau jalon pour la compréhension des occupations paléolithiques proches de la façade atlantique. Fouillé dans le cadre du projet de construction de la ligne à grande vitesse Sud Europe Atlantique, il a livré plusieurs niveaux d’occupations qui s’intercalent dans des dépôts colluviaux et éoliens au sein desquels subsistent deux horizons de sol lessivé de rang interglaciaire, l’un actuel et l’autre fossile. L’ensemble de la séquence est cadré par six datations par luminescence. Si le contexte topographique et sédimentaire a favorisé le panachage d’industries séparées dans le temps, en particulier sur le point haut du site, le degré de conservation du site reste malgré tout étonnamment bon, particulièrement dans la partie supérieure de la séquence où l’organisation spatiale est localement bien préservée, autorisant ainsi d’intéressantes interprétations comportementales des différents groupes culturels ayant fréquenté le site. Il se singularise par une récurrence de petites occupations paléolithiques s’étalant de façon non linéaire du Moustérien jusqu’au Tardiglaciaire. Elles sont toutes matérialisées par des aires de débitage très circonscrites dans l’espace et tournées vers des productions spécialisées. Cette étude présente les principales données acquises et se focalise sur les deux niveaux les mieux conservés du site : le niveau moustérien supérieur et le niveau magdalénien. Le premier est rattaché à un technocomplexe moustérien récent (OIS3) à débitage discoïde spécifiquement tourné vers une production de pointes pseudo-Levallois via des modalités de débitage originales, particulièrement bien documentées par les remontages. Le second niveau présenté correspond à une brève occupation de la phase finale du Magdalénien orientée vers une production de grandes lames réalisée à partir de cinq blocs de silex d’origine locale.The Bois Clair site is a new benchmark for the study of the Atlantic coast area Palaeolithic settlements. Excavated during the high speed Sud Europe Atlantique train line construction project, it revealed several occupation levels, inserted in colluvial and eolian deposits displaying two argillic horizons. The sequence is chronologically established by six luminescence datings. Despite a topographic and sedimentary context leading to the mixing of chronologically distinct industries, especially at the highest point of the site, it’s state of preservation remains surprisingly good, particularly in the upper part of the sequence where the spatial organization is locally preserved, thus allowing interesting behavioral interpretations. The site stands out through recurrent and small palaeolithic settlements, dating from the Mousterian to the Late Upper Palaeolithic. These settlements all display small debitage areas, dedicated to specialized productions. This paper presents the acquired data and focuses on the two best preserved occupation levels : the Late Mousterian and Magdalenian levels. The first belongs to the late mousterian technological complex (OIS3), displaying a discoïde debitage specifically dedicated to pseudo-levallois points production, achieved through original debitage methods well documented by many refittings. The second level represents a brief Late Upper Magdalenian settlement, displaying the shaping and debitage of five local flint cores, dedicated to long blade production

    Prognostic models in COVID-19 infection that predict severity: a systematic review.

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    Current evidence on COVID-19 prognostic models is inconsistent and clinical applicability remains controversial. We performed a systematic review to summarize and critically appraise the available studies that have developed, assessed and/or validated prognostic models of COVID-19 predicting health outcomes. We searched six bibliographic databases to identify published articles that investigated univariable and multivariable prognostic models predicting adverse outcomes in adult COVID-19 patients, including intensive care unit (ICU) admission, intubation, high-flow nasal therapy (HFNT), extracorporeal membrane oxygenation (ECMO) and mortality. We identified and assessed 314 eligible articles from more than 40 countries, with 152 of these studies presenting mortality, 66 progression to severe or critical illness, 35 mortality and ICU admission combined, 17 ICU admission only, while the remaining 44 studies reported prediction models for mechanical ventilation (MV) or a combination of multiple outcomes. The sample size of included studies varied from 11 to 7,704,171 participants, with a mean age ranging from 18 to 93 years. There were 353 prognostic models investigated, with area under the curve (AUC) ranging from 0.44 to 0.99. A great proportion of studies (61.5%, 193 out of 314) performed internal or external validation or replication. In 312 (99.4%) studies, prognostic models were reported to be at high risk of bias due to uncertainties and challenges surrounding methodological rigor, sampling, handling of missing data, failure to deal with overfitting and heterogeneous definitions of COVID-19 and severity outcomes. While several clinical prognostic models for COVID-19 have been described in the literature, they are limited in generalizability and/or applicability due to deficiencies in addressing fundamental statistical and methodological concerns. Future large, multi-centric and well-designed prognostic prospective studies are needed to clarify remaining uncertainties

    Um ano de escola n'A Minha Praia – sensibilização para a problemática do lixo marinho utilizando a ciência-cidadã como ferramenta

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    Um ano de escola n’A Minha Praia – sensibilização para a problemática do lixo marinho utilizando a ciência-cidadã como ferramenta O Algarve reúne um conjunto de características que o tornam particularmente vulnerável à presença de lixo marinho e aos seus efeitos nefastos: uma orla costeira longa (aprox. 200km), um destino turístico muito popular, uma população residente concentrada no litoral e uma fração significativa da sociedade cuja subsistência depende de atividades económicas ligadas ao mar (pesca, marisqueio, extração de sal, passeios turísticos, etc.). Foi tendo em conta a magnitude e as consequências da propagação do lixo marinho na região que o Centro Ciência Viva de Tavira coordenou o projeto A Minha Praia, um dos vencedores da primeira edição do Orçamento Participativo Portugal (OPP) em 2017, e cuja execução foi garantida pela colaboração entre os três Centros Ciência Viva (CCVs) no Algarve, com o envolvimento de várias entidades regionais e nacionais. Este projeto permitiu que cerca de 933 alunos provenientes de 17 escolas fossem sensibilizados para a conservação do meio marinho, para hábitos de consumo sustentáveis e para o civismo ambiental, em simultâneo com ações de ciência-cidadã, nas quais periodicamente monitorizavam a presença de lixo marinho em seis praias da costa sul do Algarve. Ainda dentro da função didática do projeto, demonstramos a valorização do plástico (que é o maior componente do lixo marinho), aproveitando-o, reciclando-o e transformando-o em novos objetos que prolongam a sua utilidade.Esta apresentação foi dinamizada no âmbito do projecto OPP-A Minha (OPP220/437), financiado pela Ciência Viva - Agência Nacional para a Cultura Científica e Tecnológica e pela FCT - Fundação para a Ciência e Tecnologia.info:eu-repo/semantics/publishedVersio

    EuReCa ONE—27 Nations, ONE Europe, ONE Registry A prospective one month analysis of out-of-hospital cardiac arrest outcomes in 27 countries in Europe

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    AbstractIntroductionThe aim of the EuReCa ONE study was to determine the incidence, process, and outcome for out of hospital cardiac arrest (OHCA) throughout Europe.MethodsThis was an international, prospective, multi-centre one-month study. Patients who suffered an OHCA during October 2014 who were attended and/or treated by an Emergency Medical Service (EMS) were eligible for inclusion in the study. Data were extracted from national, regional or local registries.ResultsData on 10,682 confirmed OHCAs from 248 regions in 27 countries, covering an estimated population of 174 million. In 7146 (66%) cases, CPR was started by a bystander or by the EMS. The incidence of CPR attempts ranged from 19.0 to 104.0 per 100,000 population per year. 1735 had ROSC on arrival at hospital (25.2%), Overall, 662/6414 (10.3%) in all cases with CPR attempted survived for at least 30 days or to hospital discharge.ConclusionThe results of EuReCa ONE highlight that OHCA is still a major public health problem accounting for a substantial number of deaths in Europe.EuReCa ONE very clearly demonstrates marked differences in the processes for data collection and reported outcomes following OHCA all over Europe. Using these data and analyses, different countries, regions, systems, and concepts can benchmark themselves and may learn from each other to further improve survival following one of our major health care events

    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
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