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81.
Four ‘clean label’ formulations for fish burgers made with mechanically separated fish meat were characterised in sensory, textural and chemical terms. The formulations differed in the ratios of European sea bass to rainbow trout (50:50 and 30:70) and the ratios of fish to potato flakes (dry matter ratio, DMR: 2.5:1 and 1.5:1). The sensory profile was mainly influenced by DMR. Recipes with the higher DMR were positively correlated with sandy, dry and crusty attributes, salty taste and overall flavour. Soft texture was perceived for recipes with the lower DMR, although no differences in texture were detected by a texturometer. Lowering DMR increased ash and water content and decreased protein content, as expected. The results indicated that 100 g of burger provided more essential fatty acids than the recommended daily intake, irrespective of formulation. In conclusion, multiple factor analysis indicated that the main changes detected and perceived were due to DMR.  相似文献   
82.
This paper presents a new 3D design paradigm for the development of specific custom-fit products, such as the soft socket of prostheses for lower limb amputees. It is centered on the digital model of the human body and, contrarily to the traditional process almost manually based, it considers the integration of methods and tools coming from different research and application fields: Reverse Engineering, Medical Imaging, Virtual Prototyping, Physics-based Simulation, and Rapid Prototyping. The paper describes the techniques adopted to acquire and create the digital model of the residual limb, the procedure to generate the socket model, the strategy developed for the functional simulation of the socket-stump interaction and, finally, the realization of the physical prototype. Each design step is described with the related problems and the obtained results. Both trans-tibial and trans-femoral amputees have been considered; however, for now the complete process has been validated for trans-tibial prostheses. Major outcomes of the proposed approach stand in a better quality of the final product, in a shorter involvement of the amputee implying a lower psychological impact, in a limited use of physical prototypes, and in a shorter development time. Moreover, the resulting paradigm answers to the Collaborative Engineering guidelines by optimizing the interaction between different domains and enhancing their contributions in a homogeneous development framework.  相似文献   
83.
"Sociotropic" people are supposedly vulnerable to dysphoria after negative interpersonal events, whereas "autonomous" people are supposedly vulnerable to achievement-related failures. The present study examined whether these personality styles are borne out in social comparison processes. For 3 weeks, 27 sociotropic and 35 autonomous undergraduates completed records of their social comparisons. Depressive personality style moderated comparison frequency and the affective consequences of comparisons, especially for dysphoric individuals: Dysphoric respondents were especially likely to make comparisons in domains that were congruent with their personalities, and comparisons in congruent domains were associated with greater mood change than comparisons in other domains, perhaps especially for dysphoric respondents. These results have implications for the literatures on social comparison and on depressive personality styles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Heavy metals are toxic environmental pollutants associated with severe ecological and human health risks. Among them is mercury (Hg), widespread in air, soil, and water, due to its peculiar geo-biochemical cycle. The clinical consequences of Hg exposure include neurotoxicity and nephrotoxicity. Furthermore, increased risk for cardiovascular diseases is also reported due to a direct effect on cardiovascular tissues, including endothelial cells, recently identified as important targets for the harmful action of heavy metals. In this review, we will discuss the rationale for the potential use of erythrocytes as a surrogate model to study Hg-related toxicity on the cardiovascular system. The toxic effects of Hg on erythrocytes have been amply investigated in the last few years. Among the observed alterations, phosphatidylserine exposure has been proposed as an underlying mechanism responsible for Hg-induced increased proatherogenic and prothrombotic activity of these cells. Furthermore, following Hg-exposure, a decrease in NOS activity has also been reported, with consequent lowering of NO bioavailability, thus impairing endothelial function. An additional mechanism that may induce a decrease in NO availability is the generation of an oxidative microenvironment. Finally, considering that chronic Hg exposure mainly occurs through contaminated foods, the protective effect of dietary components is also discussed.  相似文献   
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86.
The use of transparent organic coatings as protection for noble metal layers has a wide application especially in the costume jewellery and glass frames industry. The role of a clearcoat is to protect the noble substrate from scratches, tarnishing, and changes in gloss due to the interaction with the environment and human body. In this study electrodeposited organic coatings have been considered for this purpose. The application of clearcoats by electrophoresis usually assures a good adhesion to the substrate and the formation of a compact and protective layer. Electrophoresis has been developed especially under cathodic deposition and was mainly optimized for corrosion protection of active metals, but in this work both anodic and cathodic e-coats have been applied and analyzed. Since the substrates were noble metals, the surface could show a different reactivity during the application of the deposition voltage. The relationship between electrochemical behaviour of the substrate and the final properties of the clear coatings was investigated with electrochemical tests such as polarization curves, and electrochemical impedance spectroscopy. The correlation between deposition parameters and coatings properties as thickness and presence of defects was discussed according to the electrochemical results.  相似文献   
87.
88.
Degradation of C2-C15 volatile organic compounds in a landfill cover soil   总被引:2,自引:0,他引:2  
The composition of non-methane volatile organic compounds (hereafter VOCs) in i) the cover soil, at depths of 30, 50 and 70 cm, and ii) gas recovery wells from Case Passerini landfill site, (Florence, Italy) was determined by GC-MS. The study, based on the analysis of interstitial gases sampled along vertical profiles within the cover soil, was aimed to investigate the VOC behaviour as biogas transits from a reducing to a relatively more oxidizing environment. A total of 48 and 63 different VOCs were identified in the soil and well gases, respectively. Aromatics represent the dominant group (71.5% of total VOC) in soil gases, followed by alkanes (6.8%), ketones (5.7%), organic acids (5.2%), aldehydes (3.0%), esters (2.6%), halogenated compounds (2.1%) and terpenes (1.3%). Cyclics, heterocyclics, S-bearing compounds and phenols are ≤ 1%. In the wells the VOC composition is characterized by higher concentrations of cyclic (7.6%) and S-bearing compounds (2%) and lower concentrations of O-bearing compounds. The vertical distribution of VOCs in the cover soil shows significant variations: alkanes, aromatics and cyclics decrease at decreasing depth, whereas an inverse trend is displayed by the O-bearing species. Total VOC and CH4 concentrations at a depth of 30 cm in the soil are comparable, inferring that microbial activity is likely affecting VOCs at a very minor extent with respect to CH4. According to these considerations, to assess the biogas emission impact, usually carried out on the sole basis of CO2 and CH4 emission rates, the physical-chemical behaviour of VOCs in the cover soil, regulating the discharge of these highly contaminant compounds in ambient air, has to be taken into account. The soil vertical distribution of these species can be used to better evaluate the efficiency of oxidative capability of intermediate and final covers.  相似文献   
89.
The design of efficient and general methods for the selective oxyfunctionalization of unactivated carbon-hydrogen bonds continues to represent a major challenge for the community of chemists, despite the fact that the oxidation of alkanes is a major feature of the chemical economy. A low level of selectivity is characteristic of large-scale oxidation of hydrocarbons performed under customary industrial oxidizing conditions (e.g., the catalytic air oxidation of cycloalkanes); in these processes, selectivity is difficult to control, because they are often impacted by the usual problems associated with free-radical chain reactions. Thus, in the last decades much work has been devoted to the search for general methods of selective oxidation that could be applied to a variety of satured hydrocarbons. In this context, just a few leading methods appear encouraging at the present time. This Account addresses a new approach developed in our laboratory, consisting in the application of isolated dioxiranes, a class of powerful yet selective oxidants. We contend that the method shows promise to contribute resolution of a well-recognized general problem in the existing chemistry of alkanes, that is, to achieve efficient oxyfunctionalizations with high selectivity for simple as well as structurally complex targets.  相似文献   
90.
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