16,465 research outputs found
Desempenho e avaliação das carcaças de borregos castrados ou inteiros terminados em confinamento.
Este trabalho teve como objetivo avaliar o desempenho e a qualidade da carcaça de borregos castrados e inteiros terminados em confinamento
Natural-origin polymers as carriers and scaffolds for biomolecules and cell delivery in tissue engineering applications
The present paper intends to overview a wide range of natural–origin polymers with special focus on proteins and polysaccharides (the systems
more inspired on the extracellular matrix) that are being used in research, or might be potentially useful as carriers systems for active biomolecules
or as cell carriers with application in the tissue engineering field targeting several biological tissues. The combination of both applications into a
single material has proven to be very challenging though. The paper presents also some examples of commercially available natural–origin
polymers with applications in research or in clinical use in several applications. As it is recognized, this class of polymers is being widely used due
to their similarities with the extracellular matrix, high chemical versatility, typically good biological performance and inherent cellular interaction
and, also very significant, the cell or enzyme-controlled degradability. These biocharacteristics classify the natural–origin polymers as one of the
most attractive options to be used in the tissue engineering field and drug delivery applications
Regularized covariance estimation for weighted maximum likelihood policy search methods
Many episode-based (or direct) policy search algorithms, maintain a multivariate Gaussian distribution as search distribution over the parameter space of some objective function. One class of algorithms, such as episodic REPS, PoWER or PI2 uses, a weighted maximum likelihood estimate (WMLE) to update the mean and covariance matrix of this distribution in each iteration. However, due to high dimensionality of covariance matrices and limited number of samples, the WMLE is an unreliable estimator. The use of WMLE leads to over-fitted covariance estimates, and, hence the variance/entropy of the search distribution decreases too quickly, which may cause premature convergence. In order to alleviate this problem, the estimated covariance matrix can be regularized in different ways, for example by using a convex combination of the diagonal covariance estimate and the sample covariance estimate. In this paper, we propose a new covariance matrix regularization technique for policy search methods that uses the convex combination of the sample covariance matrix and the old covariance matrix used in last iteration. The combination weighting is determined by specifying the desired entropy of the new search distribution. With this mechanism, the entropy of the search distribution can be gradually decreased without damage from the maximum likelihood estimate
Qualidade da silagem pré-secada de Capim-TIFTON 85 cortado em três idades e três tempos de emurchecimento.
bitstream/item/31505/1/comunicado-220.pd
Does time constrain affect consumer intention to purchase? A case study with orange/pomegranate juice.
The influence of time pressure on consumer perception may be particularly relevant for the design of food packages. The aim of the present work was to evaluate the influence of time-constraint on results from a rating-based conjoint task, using pomegranate/orange juice as case study. One hundred consumers evaluated the intention to purchase of images of juice bottles, which were designed by manipulating the following variables: bottle design, front-of-pack nutritional information, nutrition claim and processing claim. They were randomly divided into two experimental conditions: control and time-constraint. Consumers with a time-constraint gave significantly higher intention to purchase scores than those in control condition, but time-constraint did not largely modify the way in which consumers evaluated their intention to purchase. In both experimental conditions consumers gave higher intention to purchase scores for bottles with traditional design, which included processing claim and front-of-pack nutritional information. Result suggests that graphic design could help consumers to make healthier food choices.Food: the tree that sustains life. 1648
Analysis of the effect of renal excretory system cooling during thermal radiofrequency ablation in an animal model
Analysis of renal excretory system integrity and efficacy of radiofrequency ablation with and without irrigation with saline at 2 o C (SF2). The median third of sixteen kidneys were submitted to radiofrequency (exposition of 1 cm) controlled by intra-surgical ultrasound, with eight minutes cycles and median temperature of 90 o C in eight female pigs. One excretory renal system was cooled with SF2, at a 30ml/min rate, and the other kidney was not. After 14 days of post-operatory, the biggest diameters of the lesions and the radiological aspects of the excretory system were compared by bilateral ascending pyelogram and the animals were sacrificed in order to perform histological analysis. There were no significant differences between the diameters of the kidney lesions whether or not exposed to cooling of the excretory system. Median diameter of the cooled kidneys and not cooled kidneys were respectively (in mm): anteroposterior: 11.46 vs. 12.5 (p = 0.23); longitudinal: 17.94 vs. 18.84 (p = 0.62); depth: 11.38 vs. 12.25 (p = 0.47). There was no lesion of the excretory system or signs of leakage of contrast media or hydronephrosis at ascending pyelogram. Cooling of excretory system during radiofrequency ablation does not significantly alter generated coagulation necrosis or affect the integrity of the excretory system in the studied model401939
Comunicação interatrial: consequências e diagnóstico
O nosso coração possui quatro cavidades, átrios direito e esquerdo e ventrículos direito e esquerdo, as quais são separas por septos de tecido fibroso. Esses septos impedem que o sangue dos átrios ou dos ventrículos se misturem, já que fisiologicamente o sangue deveria passar apenas de átrio para ventrículo do mesmo lado, ou seja, do átrio direito (AD) para o ventrículo direito (VD), como do átrio esquerdo (AE) para o ventrículo esquerdo (VE). Com isso várias patologias podem interferir nessa normofisiologia cardíaca, como exemplo a cardiopatia analisada neste trabalho, a comunicação interatrial. A comunicação interatrial é uma cardiopatia caracterizada pela comunicação entre os átrios, ou seja, há uma abertura no septo interatrial, a qual permite a passagem do sangue do átrio esquerdo para o átrio direito. Pode ser causada por defeitos no Ostium secundum (forame oval), o mais frequente, no seio venoso, no Ostium primum, no seio coronário ou por átrio único (quando não há nenhuma septação interatrial). Seu diagnóstico pode ser dado através de eletrocardiograma e seu tratamento é apenas cirúrgico. Essa cardiopatia pode ser previamente diagnosticada através do eletrocardiograma fetal, no qual se é identificado que as bordas do orifício são hiper-refrigerantes e não viabiliza a membrana do forame oval, ou aos casos de átrio comum, que não apresentam septo atrial. Este trabalho tem como objetivo reavaliar uma revisão da literatura sobre o tema proposto no intuito de revisar as principais consequências da má formação do septo interatrial e suas formas de diagnóstico
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