10 research outputs found

    Contribuição para o conhecimento da biologia de Athyaephyra desmaresti Millet : Alguns aspectos de dinâmica populacional e do balanço energético

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    Dissertação de Doutoramento em Biologia, área de especialização em Ecologia Animal, apresentada à Faculdade de Ciências da Universidade do Port

    Influence of filtration and glucose amendment on bacterial growth rate at different tidal conditions in the Minho Estuary River (NW Portugal)

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    Bacterioplankton abundance, biomass and growth rates were studied in theMinho Estuary River (NW Portugal). The influence of tidal conditions, glucose amendment, and the filtration process on total bacterial abundance, total and faecal coliforms, as well as faecal streptococci, were evaluated in laboratory incubation experiments. Physical and chemical conditions, as well as bacterial abundance in this estuary were found to be typical for oligo-mesotrophic coastal ecosystems. Bacterial abundance was higher at high tide, probably due to hydrodynamics and resuspension of bacteria from sediments. In contrast, a significant decrease of bacterial indicators of faecal pollution at high tide was probably the result of various causes, such as the decrease of continental and agricultural land run-off effect by dilution, and/or increase in the abundance of potential specific predators. Thus, drastic changes were induced at high tide that led to a lack of bacterial growth and the net disappearance of most of the bacterial populations. Glucose amendment, at used concentration, was not found to stimulate bacterial growth, which instead could be limited by inorganic nutrients.La abundancia, la biomasa y las tasas de crecimiento de bacterioplancton fueron estudiadas en el estuario del río Miño (NW Portugal). La influencia de condiciones de marea, de la adición de glucosa y del proceso de filtración en la abundancia total de bacterias, coliformes totales y coliformes fecales, así como de estreptococos fecales, fue evaluada en experimentos de incubación en laboratorio. Las condiciones físicas y quíımicas, así como la abundancia bacteriana encontradas en este estuario son típicas para los ecosistemas costeros oligo-mesotroficos. La abundancia bacteriana fue más alta en la alta marea, probablemente debido a la hidrodinámica y a la resuspensión de bacterias de los sedimentos. En contraste, la disminución significativa de los indicadores bacterianos de la contaminación fecal en la alta marea resultó probablemente de varias causas, tales como la disminución del efecto de vertido de la región continental y agrícola por la dilución, y/o aumento en la abundancia de depredadores específicos potenciales. En resultado, cambios drásticos fueron inducidos en la alta marea originando la ausencia de crecimiento bacteriano y la desaparición neta de la mayoría de las poblaciones bacterianas. La adición de la glucosa, en la concentración usada, no estimuló el crecimiento bacteriano, que se podría limitar por los alimentos inorgánicos

    Cold-tolerant traits that favour northwards movement and establishment of Mediterranean and Ponto-Caspian alien aquatic invertebrates

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    Embargo until 26 July 2023Over recent decades, many Mediterranean and Ponto-Caspian aquatic invertebrate species have dispersed northwards and established as non-native species in colder regions. We hypothesized that these species have cold-tolerant traits, which facilitate dispersal into colder climates. Thanks to these traits, Southern European aquatic species are able to cross biogeographic boundaries. We downloaded the list of all alien invertebrate species that were fully aquatic (i.e. lacking terrestrial adults) from the GRIIS database and picked out those Mediterranean and Ponto-Caspian species that have undergone northwards range expansion. We identified traits that may facilitate dispersal to colder climates including the following: small size; capacity for behavioural thermoregulation; feeding habit (omnivorous, filter-feeders, food generalists); quiescence and dormancy (or diapause); freezing avoidance (presence of cryoprotectants); tolerance to low temperatures or eurythermicity; active dispersal; and enhanced reproduction. We statistically tested the null hypotheses that Mediterranean and Ponto-Caspian alien aquatic invertebrate species that dispersed into the north have all of these traits. We used contingency tables populated with raw frequency data with χ2—tests and assessed statistical significance at α of 0.05. We identified 95 Mediterranean and Ponto-Caspian alien aquatic invertebrate species that have shown northwards range extension, 10 (10%) of which were of Mediterranean origin and 85 (90%) of Ponto-Caspian origin. We found that this northwards dispersal from Southern Europe is mainly limited to a few following groups of aquatic invertebrates: small crustaceans, molluscs, cnidarians and annelids. Ability to go to diapause, hibernation or resting period, temperature tolerance and small size were the traits most commonly shared by these organisms. We conclude that Mediterranean and Ponto-Caspian aquatic invertebrate species showing northwards range expansion have cold-tolerant strategies. The traits analysed can favour the establishment of the species.acceptedVersio

    Clinical features and prognostic factors of 245 Portuguese patients hospitalized with COVID-19

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    Introduction Since the declaration of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in March 2020, Portugal was considered a role model with regards to the first COVID-19 wave. However, a third wave started in 2021 started, turning the country into the worst in the world regarding new infections and death rate per capita in the last weeks of January 2021. No significant data regarding the country's first wave of hospitalized patients have been published. Those data may help understand the differences over time regarding patients and the clinical approach to them. Herein, we present data of COVID-19 patients hospitalized at the main tertiary hospital of the second-most affected county at the time and identify risk factors associated with disease progression and outcomes. Materials and methods We performed a prospective observational study of patients admitted with COVID-19 to a central hospital between March 20 and June 1, 2020. The primary endpoint of this study was 30-day mortality or the need for ventilatory support and the secondary outcomes were both outcomes individually. Results 245 patients were included, with a median age of 79 years, 52% males. Hypertension (n = 172) and dyslipidemia (n = 114) were the most frequent comorbidities. Half of the patients (n = 121) were treated with hydroxychloroquine. The primary outcome occurred in 114 patients; mortality at 30 days was 35%. Age (OR 1.05; 1.02-1.07) and active cancer (OR 3.89; 1.43-10.57) were associated with the primary outcome, with dyslipidemia being protective (OR 0.46; 0.25-0.80). Treatment with hydroxychloroquine or lopinavir/ritonavir was not associated with the main outcome. Patients who had been symptomatic for more than 7 days had lower mortality (OR 0.23; 0.09-0.63). Discussion In the present study, age and cancer were associated with higher mortality, as noted in prior articles. The population had a higher median age than reported in previous studies, which may explain the increased mortality. The protective association of dyslipidemia was not previously described. This association was not related to statin intake. Conclusion The reported high mortality of COVID-19 is rarely seen in other infectious diseases. Our elderly population probably reflects more reliably the incidence of COVID-19 in European countries with constricted age pyramids.publishe

    The role of the freshwater shrimp atyaephyra desmarestii in leaf litter breakdown in streams

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    This version does not correspond to the published one. To access the final version go to: http://www.springerlink.com/content/a31518u452m03286/In aquatic ecosystems, microorganisms and invertebrates provide critical links between plant detritus and higher trophic levels. Atyaephyra desmarestii is an omnivorous decapod that inhabits freshwaters and exhibits high tolerance to temperature oscillations and high ability to colonize new habitats. Although A. desmarestii is able to ingest a variety of foods, few studies have been conducted to elucidate the role of this freshwater shrimp on detritus breakdown in streams. In this study, A. desmarestii was allowed to feed on conditioned or unconditioned alder and eucalyptus leaves in microcosms with or without access to its fecal pellets. At the end of the experiment, total body length of the animals was measured, and the remaining leaves and fecal pellets were used for dry mass quantification and assessment of bacterial and fungal diversity by denaturing gradient gel electrophoresis (DGGE). Cluster analyses of DGGE fingerprints indicated that the major differences in microbial communities on leaves were between leaf types, while on fecal pellets were between conditioned and unconditioned leaves. However, the consumption rate by the shrimp did not differ between leaf types, and was significantly higher on leaves conditioned by microorganisms and in treatments without access to feces. In treatments without access to feces, the production of feces and fine particulate organic matter was also significantly higher for conditioned leaves. Overall, our results support the feeding plasticity of A. desmarestii and its potential role in plant litter breakdown in streams. This might have implications for maintaining stream ecosystem functioning, particularly if more vulnerable shredders decline.The Portuguese Foundation for the Science and Technology supported S. Duarte (SFRH/BPD/47574/2008

    2nd Meeting for Accessibility and Inclusion in Art and Heritage : book proceedings

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    Obra publicada por ocasião do Segundo Encontro de Acessibilidade e Inclusão na Arte e no Património, decorrido nos dias 24 e 25 de junho de 2022 Resumo2ª edição do encontro Acessibilidade e Inclusão na Arte e no Património é uma iniciativa da Faculdade de Belas-Artes da Universidade de Lisboa e do Museu da Farmácia. Tem como objetivo ser um espaço de discussão e troca de ideias, reunindo trabalhos associados à acessibilidade à arte e ao património cultural. Divulgando estratégias que visam melhorar o acesso e a inclusão dos diversos públicos, nomeadamente de públicos com deficiência, ao património. Este livro de atas reúne nove artigos. São abordados temas associados à teoria e legislação sobre acessibilidade e inclusão no património; avaliação da acessibilidade nos museus; experiências multissensoriais em museus e monumentos e ainda o desenvolvimento de produtos que promovam acessibilidade em museus. O Encontro contou com a participação de investigadores e profissionais da área provenientes de várias instituições nacionais e internacionaisinfo:eu-repo/semantics/publishedVersio

    Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

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    Background Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates

    Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

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    Background: Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods: WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings: Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0-4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2-6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation: In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates. Funding: European Society of Intensive Care Medicine, European Respiratory Society

    Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

    No full text
    International audienceBackground: Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods: WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings: Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation: In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates. Funding: European Society of Intensive Care Medicine, European Respiratory Society
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