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21.
An atoxigenic strain of Penicillium camemberti was superficially inoculated on fermented sausages in an attempt to improve their sensory properties. The growth of this mould on the surface of the sausages resulted in an intense proteolysis and lipolysis, which caused an increase in the concentration of free amino acids, free fatty acids (FFA) and volatile compounds. Many of these were derived from amino acid catabolism and were responsible for the "ripened flavour", i.e. branched aldehydes and the corresponding alcohols, acids and esters. The development of the fungal mycelia on the surface of the sausages also protected lipids from oxidation, resulting in both lower 2-thiobarbituric acid (TBARS) values and lipid oxidation-derived compounds, such as aliphatic aldehydes and alcohols. The sensory analysis of superficially inoculated sausages showed clear improvements in odour and flavour and, as a consequence, in the overall quality of the sausages. Therefore, this strain is proposed as a potential starter culture for dry fermented sausage production.  相似文献   
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Scaffolds functionalized with delivery systems for the release of growth factors is a robust strategy to enhance tissue regeneration. However, after implantation, macrophages infiltrate the scaffold, eventually initiating the degradation and clearance of the delivery systems. Herein, it is hypothesized that fully embedding the poly(d,l ‐lactide‐co‐glycolide acid) microspheres (MS) in a highly structured collagen‐based scaffold (concealing) can prevent their detection, preserving the integrity of the payload. Confocal laser microscopy reveals that non‐embedded MS are easily internalized; when concealed, J774 and bone marrow‐derived macrophages (BMDM) cannot detect them. This is further demonstrated by flow cytometry, as a tenfold decrease is found in the number of MS engulfed by the cells, suggesting that collagen can cloak the MS. This correlates with the amount of nitric oxide and tumor necrosis factor‐α produced by J774 and BMDM in response to the concealed MS, comparable to that found for non‐functionalized collagen scaffolds. Finally, the release kinetics of a reporter protein is preserved in the presence of macrophages, only when MS are concealed. The data provide detailed strategies for fabricating three dimensional (3D) biomimetic scaffolds able to conceal delivery systems and preserve the therapeutic molecules for release.  相似文献   
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Mobile robots and smart environments are two areas of research that can easily profit from each other. Smart environments, which are spaces unobtrusively equipped with sensors and actuators, providing ambient services to the people living within. Mobile robots inside those smart environments can use the existing infrastructure to increase their performance while decreasing the cost of local sensor systems. On the other side, evaluation of ambient services is often a laborious task. This work presents an approach that simplifies the evaluation by making use of two frameworks from robotics to perform tests in simulated smart environments. A method based on the language as action principle is used to extract realistic behavior of people living in real-world smart environments. Using this data, many different scenarios with varying configurations (different floor layouts, numbers and types of sensors, different number of people and pets) can easily be simulated and the performance of the ambient services evaluated.  相似文献   
26.
Networks-on-Chip (NoC) is an interesting option in design of communication infrastructures for embedded systems. It provides a scalable structure and balanced communication between the cores. Parallel applications that take advantage of the NoC architectures, are usually are communication-intensive. Thus, a big deal of data packets is transmitted simultaneously through the network. In order to avoid congestion delays that deteriorate the execution time of the implemented applications, an efficient routing strategy must be thought of carefully. In this paper, the ant colony optimization paradigm is explored to find and optimize routes in a mesh-based NoC. The proposed routing algorithms are simple yet efficient. The routing optimization is driven by the minimization of total latency during packets transmission between the tasks that compose the application. The presented performance evaluation is threefold: first, the impact of well-known synthetic traffic patterns is assessed; second, randomly generated applications are mapped into the NoC infrastructure and some synthetic communication traffics, that follow known patterns, are used to simulate real situations; third, sixteen real-world applications of the E3S and one specific application for digital image processing are mapped and their execution time evaluated. In both cases, the obtained results are compared to those obtained with known general purpose algorithms for deadlock free routing. The comparison avers the effectiveness and superiority of the ant colony inspired routing.  相似文献   
27.
Transparency is an extremely important optical property of several glazes used in the ceramic tile sector. The present work aimed to identify the causes of loss of transparency presented by some ceramic glazes composed of frits with chemical compositions typical of optically transparent glasses. After identifying the causes of low transparency presented by several ceramic glazes based on microstructural analyses, X-ray diffraction and scanning electron microscopy, attempts were made to increase the transparency of these glazes by altering their chemical compositions. The results suggest that the addition of alumina – through distinct mineral sources – may be an interesting alternative to prevent the crystallization of calcium silicates, which reduce the transparency of glazes used in the ceramic tile sector.  相似文献   
28.
Application of a dynamic microwave power system in the chemical synthesis of some phenothiazine and quinoline derivatives is described. Heterocyclic ring formation, aromatic nucleophilic substitution and heterocyclic aldehydes/ketones condensation reactions were performed on solid support, or under solvent free reaction conditions. The microwave-assisted Duff formylation of phenothiazine was achieved. Comparison of microwave-assisted synthesis with the conventional synthetic methods demonstrates advantages related to shorter reaction times and in some cases better reaction yields.  相似文献   
29.
The effect of the inoculation of dry fermented sausage surface with an atoxigenic, proteolytic and lipolytic strain of Mucor racemosus, Penicillium aurantiogriseum and Penicillium camemberti on the volatile composition was studied. The analysis of the headspace volatile compounds using gas chromatography/mass spectrometry enabled the identification of 55 volatiles. The study showed that every mould species produced a different volatile profile which was also different from that of the control sausages. Compounds derived from amino acid catabolism, i.e. branched aldehydes and the corresponding alcohols, were produced in higher amounts in sausages inoculated with Penicillium spp. On the other hand, volatiles coming from the microbial esterification were related to sausages inoculated with M. racemosus. The development of the fungal mycelia on the sausage surface protected lipids from oxidation, thus giving rise to fewer lipid oxidation products in the inoculated sausages.  相似文献   
30.
Spent coffee grounds (SCG), which are the residue obtained from the treatment of coffee with hot water or steam, can be used for industrial applications, due to the high content in lipids. The cosmetic products might be a suitable application for these types of residues because the barrier properties of the stratum corneum (SC) are largely dependent on the intactness of the lipid lamellae that surrounds the corneocytes. The purpose of this work was to assess the feasibility of using the lipid fraction of SCG extracted with supercritical carbon dioxide in the development of new cosmetic formulations with improved skin lipids (sebum) and hydration. The use of spent coffee lipid extract in cosmetic industry seems to be a suitable approach to recycle the wastes from coffee industry. Emulsion containing 10% of the lipid fraction of SCG (SpentCofOil cream) presented promising characteristics in the improvement of sebum skin levels with a good acceptance by consumers when compared to an emulsion containing 10% w/w of green coffee oil (GreenCofOil cream) and a placebo without coffee oil (NoCofOil cream). Practical applications: In this work, the authors develop and characterize a cream containing 10% of the lipid fraction of SCG extracted with supercritical carbon dioxide with improved skin lipids (sebum) and hydration.  相似文献   
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