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1.
Lobster krill (Munida genus) represents an under‐valued crustacean frequently caught on European fishing banks. In this work, its sensory, microbiological and biochemical qualities were evaluated during chilled storage. Additionally, the effects of a prestorage antimelanosic treatment consisting of soaking in sodium metabisulphite (SMB) solutions at two different concentrations (0.25% and 0.75%) were also studied. SMB prestorage treatment provided lobster specimens that still exhibited acceptable sensory quality after 10 days of storage, while control specimens were unacceptable at that time. SMB treatment also resulted in a significant (P < 0.05) inhibition of microbial growth, mainly of Enterobacteriaceae, psychrotrophes and proteolytic bacteria. Low lipid oxidation levels were observed for all batches; however, a significantly higher (P < 0.05) retention of polyunsaturated fatty acids was found in SMB‐treated lobster, especially in the 0.75% SMB batch. The results presented here open the way to the potential commercialisation of currently under‐utilised lobster krill as a chilled product.  相似文献   
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Among the non-monotonic reasoning processes, abduction is one of the most important. Usually described as the process of looking for explanations, it has been recognized as one of the most commonly used in our daily activities. Still, the traditional definitions of an abductive problem and an abductive solution mention only theories and formulas, leaving agency out of the picture. Our work proposes a study of abductive reasoning from an epistemic and dynamic perspective. In the first part we explore syntactic definitions of both an abductive problem in terms of an agent’s information and an abductive solution in terms of the actions that modify the agent’s information. We look at diverse kinds of agents, including not only omniscient ones but also those whose information is not closed under logical consequence and those whose reasoning abilities are not complete. In the second part, we look at an existing logical framework whose semantic model allows us to interpret the previously stated formulas, and we define two actions that represent forms of abductive reasoning.  相似文献   
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Rendering animations of scenes with deformable objects, camera motion, and complex illumination, including indirect lighting and arbitrary shading, is a long‐standing challenge. Prior work has shown that complex lighting can be accurately approximated by a large collection of point lights. In this formulation, rendering of animation sequences becomes the problem of efficiently shading many surface samples from many lights across several frames. This paper presents a tensor formulation of the animated many‐light problem, where each element of the tensor expresses the contribution of one light to one pixel in one frame. We sparsely sample rows and columns of the tensor, and introduce a clustering algorithm to select a small number of representative lights to efficiently approximate the animation. Our algorithm achieves efficiency by reusing representatives across frames, while minimizing temporal flicker. We demonstrate our algorithm in a variety of scenes that include deformable objects, complex illumination and arbitrary shading and show that a surprisingly small number of representative lights is sufficient for high quality rendering. We believe out algorithm will find practical use in applications that require fast previews of complex animation.  相似文献   
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A preliminary study of velocity fluctuations in simple devices using an atomistic model for the ionized impurity scattering is presented. The velocity fluctuations are responsible for thermal noise in semiconductor devices. In this paper the influence on the spectral density of velocity fluctuations of the boundary conditions, the doping level, the length of the resistors and the excess/default of impurities has been addressed.  相似文献   
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This work describes the evaluation of pure α-Tricalcium Phosphate (TCP) and silica containing TCP ceramics in the system Dicalcium Silicate–Tricalcium Phosphate (C2S–TCP) as a potential substrate for bone tissue engineering. The ceramics were soaked in dynamic simulated body fluid (SBF) for 2 weeks and characterized by SEM-WDS, XRD, and TEM analysis, and the results indicated that a carbonated hydroxyapatite (CHA) was formed on the surface of the ceramics. In addition, cell attachment assay showed that the ceramics supported the adult mesenchymal stem cells of human origin (hMSCs-A) adhesion and spreading, and the cells established close contacts with the ceramics after 24 h of culture. Also, cellular assays have shown a greater ability of hMSCs-A to express markers of the osteoblast phenotype (ALP, Col I, OC) in the C2S doped α-TCP ceramics, indicating osteoblastic differentiation as a result of the increased concentration of silicon in solid solution in α-TCP. These findings indicate that the C2S doped α-TCP ceramics possess good bioactivity, and biocompatibility, and might be promising for bone implant material.  相似文献   
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Epistemic logic with its possible worlds semantic model is a powerful framework that allows us to represent an agent’s information not only about propositional facts, but also about her own information. Nevertheless, agents represented in this framework are logically omniscient: their information is closed under logical consequence. This property, useful in some applications, is an unrealistic idealisation in some others. Many proposals to solve this problem focus on weakening the properties of the agent’s information, but some authors have argued that solutions of this kind are not completely adequate because they do not look at the heart of the matter: the actions that allow the agent to reach such omniscient state. Recent works have explored how acts of observation, inference, consideration and forgetting affect an agent’s implicit and explicit knowledge; the present work focuses on acts that affect an agent’s implicit and explicit beliefs. It starts by proposing a framework in which these two notions can be represented, and then it looks into their dynamics, first by reviewing the existing notion of belief revision, and then by introducing a rich framework for representing diverse forms of inference that involve both knowledge and beliefs.  相似文献   
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