3,309 research outputs found
Expressão temporal do gene nced em plantas de algodão colorido submetidas a estresse hídrico.
Expression of NCED gene in colored cotton genotypes subjected to water stress.
Considering that the NCED gene acts on the biosynthetic cascade of ABA, a hormone involved in the functioning of stomata and consequently in the regulation of transpiration, the aim of this research was to analyze the expression of this gene in colored cotton genotypes subjected to water stress at the beginning of plant growth. Four colored cotton genotypes were used, subjected to two managements, with and without water stress, beginning the treatments when the blade of the first true leaves reached an area that allowed the evaluation of gas exchange. For the studies of the expression of the NCED gene, via RT-qPCR, leaves were collected on three distinct dates: at 4 and 6 days of water stress, and after the plants regained their turgor. The differential expression of NCED was found in all genotypes, with higher levels of expression related to six days of water stress. When the stomatal conductance was around 25%, there was overexpression in the genotype CNPA 2009.13, followed by CNPA 2009.6, BRS SAFIRA and CNPA 2009.11, confirming the data obtained in the semi-quantitative RT-PCR. The NCED gene is involved in the response to water stress in the vegetative phase of colored cotton
Fast stable direct fitting and smoothness selection for Generalized Additive Models
Existing computationally efficient methods for penalized likelihood GAM
fitting employ iterative smoothness selection on working linear models (or
working mixed models). Such schemes fail to converge for a non-negligible
proportion of models, with failure being particularly frequent in the presence
of concurvity. If smoothness selection is performed by optimizing `whole model'
criteria these problems disappear, but until now attempts to do this have
employed finite difference based optimization schemes which are computationally
inefficient, and can suffer from false convergence. This paper develops the
first computationally efficient method for direct GAM smoothness selection. It
is highly stable, but by careful structuring achieves a computational
efficiency that leads, in simulations, to lower mean computation times than the
schemes based on working-model smoothness selection. The method also offers a
reliable way of fitting generalized additive mixed models
Avaliação in vitro da qualidade do sêmen de reprodutores caprinos portadores da artrite encefalite caprina (CAE) através de espermograma.
Resumo: Objetivou-se com esse estudo avaliar a qualidade do sêmen de animais portadores do CAEV através de espermograma completo. Foram realizadas 17 coletas alternadas ao longo de cinco meses (março a julho de 2013), utilizando-se de 10 reprodutores caprinos, dos quais quatro da raça Anglo-nubiano e seis Saanen, com idade entre 12 e 24 meses divididos em dois grupos (jovens-negativos e adultos-positivos para CAE) com cinco animais cada, submetidos à coleta artificial de sêmen por meio de vagina artificial, modelo curto, conjugado como uma fêmea com estro induzido. À medida que o sêmen era coletado o mesmo era destinado ao Laboratório de Tecnologia de Sêmen para realização do espermograma, onde se quantificaram os seguintes parâmetros: volume (mL), concentração espermática (x109sptz/mL), motilidade individual progressiva (MIP, 0-100%), e vigor (0-5) de acordo com os critérios preconizados pelo Colégio Brasileiro de Reprodução Animal - CBRA (1998) e os valores devidamente anotados nas fichas de avaliação. O delineamento experimental foi o inteiramente casualizado, considerando os ejaculados como sendo as repetições (N=170) e os grupos (negativo e positivo) os tratamentos. Os resultados dos parâmetros reprodutivos avaliados (volume, concentração, vigor e motilidade) nos dois grupos foram expressos por meio de média e desvio padrão de cada animal e por grupo, sendo tais médias comparadas pelo Teste de T de Student a 5% de significância. Pode-se observar que entre os animais de ambos os grupos não houve diferença significativa (p < 0,05) entre eles, e todos se encontram com as características seminais, exceto o volume no grupo dos jovens negativo, dentro dos padrões do CBRA (1998). Reprodutores caprinos portadores do CAEV não têm suas características seminais interferidas, pois mesmo apresentando a doença encontram-se com sêmen fértil e dentro da normalidade, porém com chances de transmissão da doença
Priority areas for water resources conservation: study case Canal Guandu watershed.
The environmental resilience is strictly dependent of water availability. The identification of priority areas is important to conservation aid land-use planning and urban expansion, conservation, and policy strategy. The goal was to identify priority areas aiming water provision and environmental conservation at the "Canal do Rio Guandu" watershed in Rio de Janeiro, Brazil. To address the goal four micro-basins included in the watershed were selected to optimize collect field data and create the criteria to define the priority levels. Based on prior literature, legacy and field data, an assessment method was proposed based on map algebra with support of Geographical Information System, gathering professional tacit knowledge with spatial data to support the selection of strategic areas. The approach based on was successful to select primarily priority areas and can contribute to regulate the local policies, pointing out areas that can connect legally protected areas with forested fragments, which presents great importance to urban and rural supply
Sustained remission from depressive-like behavior depends on hippocampal neurogenesis
Impairment of hippocampal neurogenesis has been associated with the expression of depressive-like symptoms and some studies have suggested neurogenesis as a critical factor in the normalization of behavior by antidepressant (AD) drugs. This study provides robust evidence that ongoing neurogenesis is essential for the maintenance of behavioral homeostasis and that its pharmacological arrest precipitates symptoms commonly found in depressed patients. Further, the incorporation of newly born neurons and astrocytes into the preexisting hippocampal neurocircuitry is shown to be necessary for the spontaneous recovery from the adverse effects of stress and for long-term benefits of AD treatments.We thank M Carneiro and L Martins for technical assistance. AM-P, LP, MM and SM received fellowships from the Portuguese Foundation for Science and Technology (FCT). This work was supported by FCT (PTDC/SAU-NEU/105180/2008) and the ICVS
Schooling for violence and peace : how does peace education differ from ‘normal’ schooling?
This article reviews literature on the roles of schooling in both reproducing and actively perpetrating violence, and sets out an historical explanation of why schools are socially constructed in such a way as to make these roles possible. It then discusses notions of peace education in relation to one particular project in England before using empirical data from research on the project to examine contrasts between peace education approaches and ‘normal’ schooling from the viewpoints of project workers, pupils and teachers. It concludes that such contrasts and tensions do indeed exist and that this raises serious questions about the compatibility of peace education and formal schooling
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