58 research outputs found
Existe diferença de osmolaridade entre ejaculados de carneiros?
Apresentado no CONGRESSO NORTE NORDESTE DE REPRODUÇÃO ANIMAL, 7., 2014, Mossoró. Novos rumos para a reprodução animal no Norte e Nordeste do Brasil: anais. Mossoró, 2014
Reconcentração do sêmen congelado de carneiros por centrifugação da palheta após a descongelação: efeito sobre a viabilidade, capacitação e reação acrossomal dos espermatozóides.
Um dos problemas da técnica de inseminação artificial cervical (IAC) é o refluxo que ocorre durante este procedimento causando uma diminuição de sêmen e consequentemente dos espermatozoides disponíveis para a fertilização. A centrifugação do sêmen é uma alternativa para se depositar um elevado número de espermatozoides viáveis em pequenos volumes e que pode diminuir ou evitar o refluxo da dose inseminante na IAC. Este trabalho teve como objetivo avaliar o efeito da centrifugação da dose inseminante após a descongelação sobre a viabilidade espermática, capacitação e reação acrossomal dos espermatozoides a fim de estudar este estratégia de redução do volume da dose inseminante. Amostras de sêmen de cinco carneiros Santa Inês foram coletadas através de vagina artificial, diluídas em meio glicina-gema-leite, envasadas em palhetas de 0,25mL com concentração espermática de 400x106/mL e, congeladas de forma automatizada (refrigeração a 0,5°C/min até 5°C, estabilização por 90 minutos, congelação a 15ºC/min de 5 à -80°C e 10ºC/min de -80 à -140°C e, imersão em nitrogênio líquido à -196°C). As palhetas foram descongeladas a 37°C/30s e divididas em um grupo não centrifugado (NC) e três grupos centrifugados durante 10 minutos em três diferentes velocidades: C800, C1000 e C1200 rpm correspondendo respectivamente a 96, 150 e 217 g. Utilizando-se um microscópio de epifluorescência, foram mensurados, logo após a descongelação e incubação (37°C) por 2 e 4h, a integridade das membranas plasmática (IMP), pela combinação dos fluorocromos SYBR®green e iodeto de propídio e, o status de capacitação e reação acrossomal dos espermatozoides pela clortetraciclina (CTC). Os percentuais de IMP obtidos nos grupos centrifugados a 800 e 1000 rpm não diferiram (p>0,05) do grupo controle não centrifugado em todos os momentos. Por outro lado, a centrifugação a 1200 rpm aumentou (p<0,05) o número de células lesadas em todos os tempos de incubação. De um modo geral, a centrifugação provocou uma diminuição (p<0,05) de células não capacitadas e sem reação acrossomal. Conclui-se que os espermatozoides submetidos à centrifugação após a descongelação mantêm a sua viabilidade numa força centrífuga de 96 e 150 g, porém, até 217 g têm sua capacitação e reação acrossomal induzidas com maior frequência
Tamanho amostral na identificação de subpopulações espermáticas em carneiros Santa Inês.
A cinética espermática é importante por estar correlacionada positivamente com a fertilidade do sêmen. Estudos de cinética utilizam ferramentas estatísticas multivariadas para incrementar a acurácia na identificação de subpopulações espermáticas em ovinos; assim o tamanho amostral é importante na variabilidade do agrupamento de células. Objetivou-se estudar a influência do n amostral aleatório na identificação de subpopulações espermáticas. Foi utilizado o banco de informações digitais da análise seminal feita em 35 carneiros adultos no Laboratório de Biotecnologia da Reprodução Animal ? Embrapa Tabuleiros Costeiros; constituindo um total de 77070 observações espermáticas contendo dados de velocidades curvilínea (VCL), em linha reta (VSL) e do percurso médio (VAP), linearidade (LIN), retilinearidade (STR), índice de oscilação (WOB), deslocamento lateral da cabeça (ALH) e batimento flagelar Cruzado (BCF) dos espermatozoides. Foi utilizada a metodologia estatística de análise dos componentes principais sendo testados diferentes n amostrais: 10, 50, 100, 250, 500, 750, 1000, 1500, 2000, 3000, 5000 e 15000. A influência do n amostral na identificação de subpopulações espermáticas em carneiros Santa Inês, considerando cinco parâmetros cinéticos espermáticos foi significativa (p<0,05), onde o n amostral abaixo de 50 espermatozoides avaliados mostrou uma maior variabilidade numérica comparada aos outros tamanhos amostrais. Conclui-se que para identificar subpopulações espermáticas homogêneas, pode ser simulado o n amostral igual ou maior de 50 espermatozoides selecionados aleatoriamente e com pelo menos 10 repetições
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
Climate and land-use changes effects on the distribution of a regional endemism: Melanophryniscus sanmartini (Amphibia, Bufonidae)
Do lignite-derived organic amendments improve early-stage pasture growth and key soil biological and physicochemical properties?
State of the climate in 2013
In 2013, the vast majority of the monitored climate variables reported here maintained trends established in recent decades. ENSO was in a neutral state during the entire year, remaining mostly on the cool side of neutral with modest impacts on regional weather patterns around the world. This follows several years dominated by the effects of either La Niña or El Niño events. According to several independent analyses, 2013 was again among the 10 warmest years on record at the global scale, both at the Earths surface and through the troposphere. Some regions in the Southern Hemisphere had record or near-record high temperatures for the year. Australia observed its hottest year on record, while Argentina and New Zealand reported their second and third hottest years, respectively. In Antarctica, Amundsen-Scott South Pole Station reported its highest annual temperature since records began in 1957. At the opposite pole, the Arctic observed its seventh warmest year since records began in the early 20th century. At 20-m depth, record high temperatures were measured at some permafrost stations on the North Slope of Alaska and in the Brooks Range. In the Northern Hemisphere extratropics, anomalous meridional atmospheric circulation occurred throughout much of the year, leading to marked regional extremes of both temperature and precipitation. Cold temperature anomalies during winter across Eurasia were followed by warm spring temperature anomalies, which were linked to a new record low Eurasian snow cover extent in May. Minimum sea ice extent in the Arctic was the sixth lowest since satellite observations began in 1979. Including 2013, all seven lowest extents on record have occurred in the past seven years. Antarctica, on the other hand, had above-average sea ice extent throughout 2013, with 116 days of new daily high extent records, including a new daily maximum sea ice area of 19.57 million km2 reached on 1 October. ENSO-neutral conditions in the eastern central Pacific Ocean and a negative Pacific decadal oscillation pattern in the North Pacific had the largest impacts on the global sea surface temperature in 2013. The North Pacific reached a historic high temperature in 2013 and on balance the globally-averaged sea surface temperature was among the 10 highest on record. Overall, the salt content in nearsurface ocean waters increased while in intermediate waters it decreased. Global mean sea level continued to rise during 2013, on pace with a trend of 3.2 mm yr-1 over the past two decades. A portion of this trend (0.5 mm yr-1) has been attributed to natural variability associated with the Pacific decadal oscillation as well as to ongoing contributions from the melting of glaciers and ice sheets and ocean warming. Global tropical cyclone frequency during 2013 was slightly above average with a total of 94 storms, although the North Atlantic Basin had its quietest hurricane season since 1994. In the Western North Pacific Basin, Super Typhoon Haiyan, the deadliest tropical cyclone of 2013, had 1-minute sustained winds estimated to be 170 kt (87.5 m s-1) on 7 November, the highest wind speed ever assigned to a tropical cyclone. High storm surge was also associated with Haiyan as it made landfall over the central Philippines, an area where sea level is currently at historic highs, increasing by 200 mm since 1970. In the atmosphere, carbon dioxide, methane, and nitrous oxide all continued to increase in 2013. As in previous years, each of these major greenhouse gases once again reached historic high concentrations. In the Arctic, carbon dioxide and methane increased at the same rate as the global increase. These increases are likely due to export from lower latitudes rather than a consequence of increases in Arctic sources, such as thawing permafrost. At Mauna Loa, Hawaii, for the first time since measurements began in 1958, the daily average mixing ratio of carbon dioxide exceeded 400 ppm on 9 May. The state of these variables, along with dozens of others, and the 2013 climate conditions of regions around the world are discussed in further detail in this 24th edition of the State of the Climate series. © 2014, American Meteorological Society. All rights reserved
Long-term outcomes of the global tuberculosis and COVID-19 co-infection cohort
Background: Longitudinal cohort data of patients with tuberculosis (TB) and coronavirus disease 2019 (COVID-19) are lacking. In our global study, we describe long-term outcomes of patients affected by TB and COVID-19. Methods: We collected data from 174 centres in 31 countries on all patients affected by COVID-19 and TB between 1 March 2020 and 30 September 2022. Patients were followed-up until cure, death or end of cohort time. All patients had TB and COVID-19; for analysis purposes, deaths were attributed to TB, COVID-19 or both. Survival analysis was performed using Cox proportional risk-regression models, and the log-rank test was used to compare survival and mortality attributed to TB, COVID-19 or both. Results: Overall, 788 patients with COVID-19 and TB (active or sequelae) were recruited from 31 countries, and 10.8% (n=85) died during the observation period. Survival was significantly lower among patients whose death was attributed to TB and COVID-19 versus those dying because of either TB or COVID-19 alone (p<0.001). Significant adjusted risk factors for TB mortality were higher age (hazard ratio (HR) 1.05, 95% CI 1.03-1.07), HIV infection (HR 2.29, 95% CI 1.02-5.16) and invasive ventilation (HR 4.28, 95% CI 2.34-7.83). For COVID-19 mortality, the adjusted risks were higher age (HR 1.03, 95% CI 1.02-1.04), male sex (HR 2.21, 95% CI 1.24-3.91), oxygen requirement (HR 7.93, 95% CI 3.44-18.26) and invasive ventilation (HR 2.19, 95% CI 1.36-3.53). Conclusions: In our global cohort, death was the outcome in >10% of patients with TB and COVID-19. A range of demographic and clinical predictors are associated with adverse outcomes
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