10 research outputs found

    A genetic survey of heavily exploited, endangered turtles : caveats on the conservation value of trade animals

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    Asian turtles face an extinction crisis, and so it is imperative that systematists accurately determine species diversity in order to guide conservation strategies effectively. We surveyed mitochondrial and nuclear DNA (mtDNA and nuDNA) variation of the heavily exploited Mauremys mutica complex, a clade of Asian turtles that contains the endangered M. mutica from Japan, Taiwan, China and Vietnam, and the critically endangered Mauremys annamensis from central Vietnam. We discovered extensive mtDNA and nuDNA variation among samples that did not correspond to the currently recognized taxonomy. Both nuDNA and mtDNA data suggest that M. mutica is paraphyletic with respect to M. annamensis. Surprisingly, M. annamensis exhibits a previously unknown mtDNA structure in the form of two clades that are paraphyletic to M. mutica. These data reveal that the currently recognized taxonomy of the mutica complex does not reflect the genetic diversity of our samples. Unfortunately, many conservation-oriented captive-breeding efforts for turtles are also based on trade samples such as the ones studied here. These efforts include plans to breed trade-rescued individuals and release their progeny into the wild. Because our genetic survey reveals that the taxonomic identity of these samples does not reflect genetic diversity, we raise serious questions about the efficacy of these programs. In order to address conservation issues and provide more accurate estimates of evolutionary lineages within Mauremys, we recommend continued surveys for wild populations of the mutica complex to provide new genetic material and additional distributional data, attempts to extract DNA from historic museum specimens and a shift in conservation focus to in situ preservation of wild populations and associated habitat

    Convalescent Plasma Antibody Levels and the Risk of Death from Covid-19

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    BACKGROUND: Convalescent plasma has been widely used to treat coronavirus disease 2019 (Covid-19) under the presumption that such plasma contains potentially therapeutic antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that can be passively transferred to the plasma recipient. Whether convalescent plasma with high antibody levels rather than low antibody levels is associated with a lower risk of death is unknown. METHODS: In a retrospective study based on a U.S. national registry, we determined the anti-SARS-CoV-2 IgG antibody levels in convalescent plasma used to treat hospitalized adults with Covid-19. The primary outcome was death within 30 days after plasma transfusion. Patients who were enrolled through July 4, 2020, and for whom data on anti-SARS-CoV-2 antibody levels in plasma transfusions and on 30-day mortality were available were included in the analysis. RESULTS: Of the 3082 patients included in this analysis, death within 30 days after plasma transfusion occurred in 115 of 515 patients (22.3%) in the high-titer group, 549 of 2006 patients (27.4%) in the medium-titer group, and 166 of 561 patients (29.6%) in the low-titer group. The association of anti-SARS-CoV-2 antibody levels with the risk of death from Covid-19 was moderated by mechanical ventilation status. A lower risk of death within 30 days in the high-titer group than in the low-titer group was observed among patients who had not received mechanical ventilation before transfusion (relative risk, 0.66; 95% confidence interval [CI], 0.48 to 0.91), and no effect on the risk of death was observed among patients who had received mechanical ventilation (relative risk, 1.02; 95% CI, 0.78 to 1.32). CONCLUSIONS: Among patients hospitalized with Covid-19 who were not receiving mechanical ventilation, transfusion of plasma with higher anti-SARS-CoV-2 IgG antibody levels was associated with a lower risk of death than transfusion of plasma with lower antibody levels. (Funded by the Department of Health and Human Services and others; ClinicalTrials.gov number, NCT04338360.)

    Efeitos da taxa de ganho de peso pré-desmama de bezerras de corte e do nível nutricional pós-parto, quando vacas, sobre a produção e composição do leite e o desempenho de bezerros Preweaning gain rate of beef heifers and postpartum nutritional level, as cows, on milk production and composition and performance of their calves

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    Foi estudada a taxa de ganho de peso de bezerras de corte na fase de aleitamento, do nascimento aos sete meses, e seu reflexo sobre o desempenho posterior, enquanto vacas. As taxas de ganho de peso avaliadas quando bezerras, durante o período pré-desmame, foram: baixa (menor que 350 g/dia) e moderada (maior que 350 g/dia). Quando vacas e após o parto, foram mantidas com seus bezerros até o desmame, em pastagem nativa (PN) ou pastagem cultivada (PC). As vacas, quando bezerras, foram pesadas ao nascer e aos sete meses de idade (desmame) e, quando vacas, foram pesadas, com seus bezerros nas primeiras 24 horas pós-parto; aos 14, 42, 70, 98, 126, 154, 182 dias; e ao desmame, que ocorreu com idade média dos bezerros de 228 dias. As avaliações da produção de leite e a coleta de amostras para avaliação da composição do leite foram realizadas nas mesmas datas das pesagens, com exceção do nascimento. Taxas de ganho de peso inferiores a 350 g/dia até os sete meses de idade não foram prejudiciais ao futuro peso das bezerras, em razão da compensação no peso que apresentaram na fase pós-desmama. Bezerras com taxas de ganho de peso menores que 350 g/dia até os sete meses de idade, enquanto vacas produziram maiores quantidades de leite (4,83 vs 3,71 L/dia), total de gordura (47,4 vs 35,9 kg), lactose (52,6 vs 39,7 kg), extrato seco total (140,4 vs 107,2 kg) e extrato seco desengordurado (94,8 vs 71,2 kg), e bezerros com maiores ganhos de peso (717 vs 617 g/dia) e mais pesados ao desmame (189,0 vs 166,1 kg) que as vacas que, quando bezerras, apresentaram taxas de ganho de peso acima de 350 g/dia.<br>The preweaning weight gain rate of beef heifers and its effects on their subsequent performance as cows, was studied. The weight gain rates evaluated as heifer calves before weaning were low (below 350 g/day) and moderate (above 350 g/day). As cows and after calving, they were kept together with their calves until weaning on native (NP) or cultivated pasture (CP). The cows while heifers were weighted at birth and at weaning with seven months. As cows they were weighted with their calves 24h after calving, at 14, 42, 70, 98, 126, 182 days postpartum, and at weaning when the calves reached average age of 228 days. The milk yield and the sampling for the evaluation of milk composition were taken at the same day of the weighing of the cows, with exception at birth. Weight rates below 350 g/day until seven months, did not affect the future weight of the heifers, due to compensatory gain after weaning. Heifers with weight gain rates below 350 g/day until seven month, as cows produced more milk (4.83 vs 3.71 L/day), total fat (47.4 vs 35.9 kg), lactose (52.6 vs 39.7 kg), total dry extract (140.4 vs 107.2 kg) and nonfat dry extract (94.8 vs 71.2 kg), calves with higher weight gain (717 vs 617 g/day) and heavier at weaning (189 vs 166.1 kg), than cows that showed as heifer-calves weight gain rates above 350 g/day

    The response of mammals to forest fire and timber harvest in the North American boreal forest

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    Breaking of axial symmetry in excited heavy nuclei as identified in giant dipole resonance data

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