986 resultados para 809
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"BLM-UT-ES-90-002-4332"--P. [4] of cover.
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Individual and combined supplementation of phosphorus-adequate, wheat-based broiler diets with exogenous phytase and xylanase was evaluated in three experiments. The effects of the enzyme combination in lysine-deficient diets containing wheat and sorghum were more pronounced than those of the individual feed enzymes. The inclusion of phytase plus xylanase improved (p<0.05) weight gains (7.3%) and feed efficiency (7.0%) of broilers (7-28 days post-hatch) and apparent metabolisable energy (AME) by 0.76 MJ/kg DM. Phytase plus xylanase increased (p<0.05) the overall, apparent ileal digestibility of amino acids by 4.5% (0.781 to 0.816); this was greater than the responses to either phytase (3.6%; 0.781 to 0.809) or xylanase (0.7%; 0.781 to 0.784). Absolute increases in amino acid digestibility with the combination exceeded the sum of the individual increases generated by phytase and xylanase for alanine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, phenylalanine, threonine, tyrosine and valine. These synergistic responses may have resulted from phytase and xylanase having complementary modes of action for enhancing amino acid digestibilities and/or facilitating substrate access. The two remaining experiments were almost identical except wheat used in Experiment 2 had a higher phytate concentration and a lower estimated AME content than wheat used in Experiment 3. Individually, phytase and xylanase were generally more effective in Experiment 2, which probably reflects the higher dietary substrate levels present. Phytase plus xylanase increased (p<0.05) gains (15.4%) and feed efficiency (7.0%) of broiler chicks from 4-24 days post-hatch in Experiment 2; whereas, in Experiment 3, the combination increased (p<0.05) growth to a lesser extent (5.6%) and had no effect on feed efficiency. This difference in performance responses appeared to be 'protein driven' as the combination increased (p<0.05) nitrogen retention in Experiment 2 but not in Experiment 3; whereas phytase plus xylanase significantly increased AME in both experiments. In Experiments 2 and 3 the combined inclusion levels of phytase and xylanase were lower that the individual additions, which demonstrates the benefits of simultaneously including phytase and xylanase in wheat-based poultry diets.
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Destacar a importância da reportagem investigativa, e mostrar o valor que deve ser observado no empenho da atuação profissional ética de um repórter de televisão, capaz de mudar o rumo da história política recente do Brasil, é o que se propõe o presente trabalho. A prática do jornalismo autêntico demonstra ser transformadora. É o que acontece com a atuação do repórter Caco Barcellos. Ele se propôs a perseguir uma história por mais de um ano e, ao final, mostrar uma verdade escondida durante 30 anos pelo poder público. Com tal reportagem, possibilitou a reparação de uma injustiça social cometida contra uma jovem estudante brasileira. A força da reportagem apresentada num telejornal é incontestável, em razão do potencial que representa a televisão na penetração em todas as camadas da sociedade como veículo de informação. Sendo a reportagem apresentada em série de três dias consecutivos pelo Jornal Nacional, eleva seu peso significativamente, devido à liderança de audiência do telejornal da Rede Globo. O investimento da emissora numa reportagem como a apresentada neste trabalho depende fundamentalmente da presença de um repórter profundamente identificado com a luta contra a injustiça social. E é este o perfil de Caco Barcellos. Ele cresceu na periferia pobre de uma metrópole, e desde muito cedo se revoltou contra a ação policial que discrimina o cidadão comum e privilegia os poderosos. Conseguiu transformar a raiva acumulada em ações efetivas através da reportagem investigativa reveladora da injustiça social cometida diariamente. Quando o espaço era pequeno para o tamanho do que tinha para reportar, Caco lançou livros, ganhou prêmios e enfrentou processos judiciais, movidos por policiais interessados em destruir a vida profissional do repórter que ousou trabalhar sério e encontrar os documentos que provavam os desmandos praticados contra inocentes, friamente assassinados. O resultado é uma atuação exemplar, com um método de trabalho digno de ser seguido, refletindo-se na série de reportagens que desmontou uma farsa montada pelo exército, e que pode ser considerada como uma verdadeira aula de jornalismo.
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Received wisdom has it that positive polarity items such as someone are incompatible with negation (?*Someone didn't come). Yet negative contexts are attested with such items not only in their specific indefinite reading (e.g. There's someone who didn't come), but also in their non-specific reading (It isn't the case that someone came). It is the non-specific reading of indefinite quelqu'un as subject of a negative verb phrase which is analysed by the present paper. On the basis of a corpus of attested cases, it demonstrates that polemic contrast is the crucial condition of the considered interpretation. As quelqu'un is included within a presupposed proposition that is rejected as a whole by negation, negative contexts can accommodate an item which does not normally yield the interpretations negation does. Interpretation is thus presented as process of mutual adjustment between contextual readings allowed for by items, readings which can be modalised by discursive values.
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Neuronal operations associated with the top-down control process of shifting attention from one locus to another involve a network of cortical regions, and their influence is deemed fundamental to visual perception. However, the extent and nature of these operations within primary visual areas are unknown. In this paper, we used magnetoencephalography (MEG) in combination with magnetic resonance imaging (MRI) to determine whether, prior to the onset of a visual stimulus, neuronal activity within early visual cortex is affected by covert attentional shifts. Time/frequency analyses were used to identify the nature of this activity. Our results show that shifting attention towards an expected visual target results in a late-onset (600 ms postcue onset) depression of alpha activity which persists until the appearance of the target. Independent component analysis (ICA) and dipolar source modeling confirmed that the neuronal changes we observed originated from within the calcarine cortex. Our results further show that the amplitude changes in alpha activity were induced not evoked (i.e., not phase-locked to the cued attentional task). We argue that the decrease in alpha prior to the onset of the target may serve to prime the early visual cortex for incoming sensory information. We conclude that attentional shifts affect activity within the human calcarine cortex by altering the amplitude of spontaneous alpha rhythms and that subsequent modulation of visual input with attentional engagement follows as a consequence of these localized changes in oscillatory activity. © 2005 Elsevier B.V. All rights reserved.
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Adiponectin is an abundantly circulating adipokine, orchestrating its effects through two 7-transmembrane receptors (AdipoR1 and AdipoR2). Steroidogenesis is regulated by a variety of neuropeptides and adipokines. Earlier studies have reported adipokine mediated steroid production. A key rate-limiting step in steroidogenesis is cholesterol transportation across the mitochondrial membrane by steroidogenic acute regulatory protein (StAR). Several signalling pathways regulate StAR expression. The actions of adiponectin and its role in human adrenocortical steroid biosynthesis are not fully understood. The aim of this study was to investigate the effects of adiponectin on StAR protein expression, steroidogenic genes, and cortisol production and to dissect the signalling cascades involved in the activation of StAR expression. Using qRT-PCR, Western blot analysis and ELISA, we have demonstrated that stimulation of human adrenocortical H295R cells with adiponectin results in increased cortisol secretion. This effect is accompanied by increased expression of key steroidogenic pathway genes including StAR protein expression via ERK1/2 and AMPK-dependent pathways. This has implications for our understanding of adiponectin receptor activation and peripheral steroidogenesis. Finally, our study aims to emphasise the key role of adipokines in the integration of metabolic activity and energy balance partly via the regulation of adrenal steroid production.
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Two eye-tracking studies and an offline experiment explored the effect of central shelf location on attention and choice. Investigation of the attention process revealed that the central gaze cascade effect, progressively increasing attention focused on the central option predicted choice.
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This paper describes a method of signal preprocessing under active monitoring. Suppose we want to solve the inverse problem of getting the response of a medium to one powerful signal, which is equivalent to obtaining the transmission function of the medium, but do not have an opportunity to conduct such an experiment (it might be too expensive or harmful for the environment). Practically the problem can be reduced to obtaining the transmission function of the medium. In this case we can conduct a series of experiments of relatively low power and superpose the response signals. However, this method is conjugated with considerable loss of information (especially in the high frequency domain) due to fluctuations of the phase, the frequency and the starting time of each individual experiment. The preprocessing technique presented in this paper allows us to substantially restore the response of the medium and consequently to find a better estimate for the transmission function. This technique is based on expanding the initial signal into the system of orthogonal functions.
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The Last Interglacial (LIG, 129-116 thousand of years BP, ka) represents a test bed for climate model feedbacks in warmer-than-present high latitude regions. However, mainly because aligning different palaeoclimatic archives and from different parts of the world is not trivial, a spatio-temporal picture of LIG temperature changes is difficult to obtain. Here, we have selected 47 polar ice core and sub-polar marine sediment records and developed a strategy to align them onto the recent AICC2012 ice core chronology. We provide the first compilation of high-latitude temperature changes across the LIG associated with a coherent temporal framework built between ice core and marine sediment records. Our new data synthesis highlights non-synchronous maximum temperature changes between the two hemispheres with the Southern Ocean and Antarctica records showing an early warming compared to North Atlantic records. We also observe warmer than present-day conditions that occur for a longer time period in southern high latitudes than in northern high latitudes. Finally, the amplitude of temperature changes at high northern latitudes is larger compared to high southern latitude temperature changes recorded at the onset and the demise of the LIG. We have also compiled four data-based time slices with temperature anomalies (compared to present-day conditions) at 115 ka, 120 ka, 125 ka and 130 ka and quantitatively estimated temperature uncertainties that include relative dating errors. This provides an improved benchmark for performing more robust model-data comparison. The surface temperature simulated by two General Circulation Models (CCSM3 and HadCM3) for 130 ka and 125 ka is compared to the corresponding time slice data synthesis. This comparison shows that the models predict warmer than present conditions earlier than documented in the North Atlantic, while neither model is able to produce the reconstructed early Southern Ocean and Antarctic warming. Our results highlight the importance of producing a sequence of time slices rather than one single time slice averaging the LIG climate conditions.