34 research outputs found

    COEFICIENTES DE SIMILARIDADE PARA AVALIAÇÃO DA DIVERSIDADE GENÉTICA EM PINHÃO-MANSO POR MARCADORES ISSR

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    Objetivou-se com este trabalho, avaliar a eficiência da utilização de diferentes coeficientes de similaridade na estimação da diversidade genética de Jatropha curcas L. utilizando marcadores moleculares ISSR. O DNA genômico foi extraído a partir de folhas jovens de 43 acessos de pinhão-manso. Matrizes de dissimilaridade genética foram obtidas a partir dos coeficientes Baroni, Coincidência Simples, Hamann, Índice II, Índice III, Jaccard, Nei e Li, Ochiai I, Ochiai II, Rogers e Tanimoto e Sokal e Sneath. Os dendrogramas foram construídos utilizando o método UPGMA e comparados mediante os parâmetros de coeficiente de correlação cofenético, estresse e distorção. Foram estimadas as correlações entre os pares de matrizes pelo teste de Mantel. Houve concordância entre as matrizes originais e as matrizes resultantes do processo de agrupamento para todos os coeficientes estudados. Os índices de Jaccard e Nei e Li não diferiram quanto ao ordenamento dos acessos avaliados e permitiram maior discriminação destes, sendo os mais adequados para avaliar a diversidade genética em pinhão-manso baseada em marcadores moleculares ISSR.Palavras-chave: dissimilaridade genética; análise de agrupamento; Jatropha curcas L. SIMILARITY COEFFICIENTS FOR EVALUATION OF GENETIC DIVERSITY IN JATROPHA BY ISSR MARKERS ABSTRACT:The aim of this work was to evaluate the efficiency of using different similarity coefficients in the estimation of Jatropha curcas L. genetic diversity using ISSR molecular markers. Genomic DNA was extracted from young leaves of the 43 jatropha accessions. Genetic dissimilarity matrices were obtained from the Baroni, Simple Matching, Hamann, Index II, Index III, Jaccard, Nei and Li, Ochiai I, Ochiai II, Rogers and Tanimoto and Sokal and Sneath coefficients. The dendrograms were constructed using the UPGMA method and compared using the co-phenetic correlation coefficient, stress and distortion parameters. Correlations between pairs of matrices were estimated by the Mantel test. There was agreement between the original matrices and the matrices resulting from the grouping process for all the studied coefficients. The Jaccard and Nei and Li indices did not differ in terms of the order of the evaluated accessions and allowed for greater discrimination of these, being the most suitable for assessing genetic diversity in physic nut based on ISSR molecular markers.Keywords: genetic dissimilarity; cluster analysis; Jatropha curcas L

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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    Meeting abstrac

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

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    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Divergence and control genetic character of production and quality of colored cotton fiber

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    O algodoeiro à a mais importante fibra tÃxtil do mundo. Entre os cultivares de algodÃo obtidos, aqueles com fibra naturalmente coloridas tem tido grande importÃncia como matÃria prima para a indÃstria tÃxtil, principalmente para atender demandas de tecidos ecolÃgicos e orgÃnicos. Nesse sentido, o presente trabalho foi conduzido com a finalidade de identificar genÃtipos de algodÃo de fibra colorida com boa produtividade e qualidade de fibra. Para tanto os objetivos especÃficos foram identificar genÃtipos contrastantes que possam ser utilizados no melhoramento do algodÃo colorido e tambÃm identificar que aÃÃes gÃnicas estÃo envolvidas no desempenho dos hÃbridos formados pelo cruzamento entre quatro cultivares de fibra colorida com seis cultivares tradicionais de fibra branca. Na primeira etapa do trabalho conduziu-se estudos de divergÃncia genÃtica nos genitores utilizados, por meio de tÃcnicas multivariadas, e na segunda etapa, foram estimados efeitos da capacidade geral de combinaÃÃo (CGC) e capacidade especÃfica de combinaÃÃo (CEC), identificando-se os tipos de aÃÃes gÃnicas envolvidas no controle das caracterÃsticas observadas por meio da metodologia REML/BLUP. Os dados foram coletados a partir da conduÃÃo de um experimento sob o delineamento de blocos casualizados com 24 tratamentos (14 hÃbridos e 10 genitores), no espaÃamento de 1,25 m entre linhas e 0,25 entre plantas e cinco plantas por parcela. Durante a colheita foram coletadas amostras de 20 capulhos de cada tratamento que foram utilizados para avaliaÃÃo de 12 caracterÃsticas tecnolÃgicas da fibra em HVI. As cultivares mais divergentes, envolvendo grupos distintos, foi entre a BRS Verde e BRS Buriti, seguidas da BRS Verde e BRS 293. As menores distÃncias foram obtidas entre as cultivares de fibra branca. Destaque para as cultivares BRS 286 e BRS 293. As caracterÃsticas CSP, %FIB, PAC e PAP foram mais importantes para a divergÃncia genÃtica entre os genitores. Os efeitos genÃticos aditivos tÃm maior importÃncia para o controle genÃtico das caracterÃsticas de produÃÃo e qualidade das fibras do algodÃo.Cotton is the most important textile fiber in the world. Among all cotton cultivars released, those with naturally colored fiber has been of great importance as a raw material for the textile industry, mainly to meet demands for ecological and organic fabrics. In this sense, the aim of this study was identify genotypes of colored cotton fiber with good yield and fiber quality. The specific objectives were identify contrasting genotypes that can be used in breeding of colored cotton and also identify gene actions that are involved in the performance of the hybrids formed by crossing between four cultivars of colored fiber with six traditional cultivars of white fiber. In the first stage of the research it was conducted studies over genetic diversity in the parents used by univariate and multivariate techniques, and in the second step, we estimated effects of general combining ability ( GCA) and specific combining ability (SCA ), identifying the types of gene actions involved in the control of the observed features, using the methodology REML/BLUP. The statistical design used in the experimental data was randomized block with 24 treatments (14 hybrids and 10 parents), spaced 1,25 m between rows and 0,25 between plants and five plants per plot. They were collected samples from 20 bolls from each treatment used to evaluate 12 technological characteristics of the fiber in HVI. The most divergent cultivars, involving different groups, was between the BRS Verde and BRS Buriti, followed by BRS 293 and BRS. Smaller distances were obtained between cultivars of white fiber. Highlight for BRS 286 and BRS 293 cultivar. The features CSP,% FIB, PAC and PAP were more important for the genetic divergence between the parents. Additive genetic effects are more important for the genetic control of the characteristics of production and quality of cotton fibers
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