4 research outputs found

    Frequência cardiaca máxima e sua recuperação

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    Since Robinson's study, published in 1938, which used age as an independent variable, do not know any other variable that can improve the prediction of maximal heart rate (HRMAX). Recently it has been studied HR recovery (HRR) after maximal exercise, which has been identified as a predictor of mortality. To better understand HRMAX and HRR after maximal test, this study aimed to: 1) Identify if the maximum heart rate is influenced by heart rate variability (HRV) at rest 2) Suggest an assessment model FCREC relativized by the values of HRMAX 3) Test the strategy of the calculation of deltas for the times of 10, 20, 30, 40, 50, 60, 120, 180, 240 and 300 s of recovery, and 4) Propose a strategy for calculating the FCREC by the percentage of recovery, as well as create an equation for predicting% FCREC. To achieve the proposed objectives, two studies were performed. Study 1 - 63 subjects were evaluated (21 women and 42 men) from 20 to 30 years. We evaluated the HR and your variability (HRV) at rest in a sitting position. Then, subjects performed a maximal cardiopulmonary exercise testing on treadmill (Bruce Protocol). The subjects were divided by gender and the median of HRMAX in group high low HRMAX. The indices of (HRV) at rest in both groups were compared by ―t‖ test of Student for independent groups (p <0.05). Only the low frequency band (LF) was significantly different between groups. We conclude that higher values of LF at rest are associated with higher HRMAX. Study 2 - 77 individuals were assessed (24 women and 53 men) from 18 to 50 years. After Bruce protocol, FC was collected for 300s after the test. Correlation of the FCREC in absolute values, deltas and percentages at 10, 20, 30, 40, 50, 60, 120, 180, 240 and 300 s with the HRMAX reached in the test. The group was also divided into groups and high and low HRMAX the median value of total group. The differences between group means were tested by ―t’ test for independent groups (p <0.05). It was observed that the absolute values of FCREC are correlated with HRMAX and thus not the best strategy for classification of that recovery. The deltas of FCREC, the fast phase (10-60 s) showed no correlation with the HRMAX. Already, in the slow phase (60 to 300 s) there was significant correlation with the HRMAX. The use of percentages of HRMAX proved to be the only strategy that at no time was correlated with the HRMAX. We constructed regression equations, one for each phase of the FCREC, to indicate the average values of recovery.Desde o estudo de Robinson, publicado em 1938, em que se utilizou a idade como variável independente, não se conhece outra variável que possa melhorar a predição da freqüência cardíaca máxima (FCMAX). Recentemente, tem se estudado a FC de recuperação (FCREC) após exercício máximo, que tem sido apontada como preditora de mortalidade. Para melhor entender a FCMAX e a FCREC após teste máximo, o presente estudo teve como objetivos: 1)Identificar se a FCMax é influenciada pela variabilidade da freqüência cardíaca (VFC) em repouso, 2) Verificar se a FCREC avaliada por meio de deltas é influenciada pela FCMAX; 3) Sugerir um modelo de avaliação da FCREC relativizado pelos valores de FCMAX. e 4) Propor uma equação que descreva a cinética de recuperação da FCMAX em indivíduos jovens e de meia idade saudáveis. Para alcançar os objetivos propostos, foram realizados dois estudos. Estudo 1 - foram avaliados 63 indivíduos (21 mulheres e 42 homens) de 20 a 30 anos. Foi avaliada a FC e VFC em repouso na posição sentada. Em seguida, os indivíduos realizaram um teste cardiopulmonar máximo em esteira (Protocolo de Bruce). Os indivíduos foram divididos, sexo e pela mediana da FCMAX, em grupo de alta de baixa FCMAX. Os índices de VFC de repouso dos dois grupos foram comparados por teste ―t‖ de Student para grupos independentes (p<0,05). Apenas a banda de baixa freqüência (LF) nas mulheres se mostrou significativamente diferente entre os grupos. Conclui-se que maiores valores de LF nas mulheres em repouso estão associadas à FCMAX mais elevadas. Estudo 2 - foram avaliados 77 indivíduos (24 mulheres e 53 homens) de 18 a 50 anos. Após o teste máximo de Bruce, foi coletada a FC durante 300s após o fim do teste. Foi feita correlação da FCREC em valores absolutos, deltas e percentuais nos tempos 10, 20, 30, 40, 50, 60, 120, 180, 240 e 300 s com a FCMAX atingida no teste. O grupo também foi dividido em grupo e alta e baixa FCMAX pelo valor da mediana do grupo total. As diferenças entre as médias dos grupos foram testadas pelo teste ―t‖ de Student para grupos independentes (p<0,05). Observou-se que os valores absolutos de FCREC se correlacionam com a FCMAX, não sendo assim a melhor estratégia para classificação dessa recuperação. Os deltas de FCREC, na fase rápida (10 a 60 s), não mostraram correlação com a FCMAX. Já, na fase lenta (60 a 300 s), foi evidenciada correlação com a FCMAX. A utilização de valores percentuais da FCMAX se mostrou a única 9 estratégia em que em nenhum momento da FCREC apresentou correlação com a FCMAX. Construíram-se equações de regressão, uma para cada fase da FCREC, para indicar os valores médios de recuperação

    Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

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    International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora
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