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21.
Exposure to repeated social stress may cause maladaptive emotional reactions that can be reduced by healthy nutritional supplementation. Histaminergic neurotransmission has a central role in orchestrating specific behavioural responses depending on the homeostatic state of a subject, but it remains to be established if it participates in the protective effects against the insults of chronic stress afforded by a healthy diet. By using C57BL/6J male mice that do not synthesize histamine (Hdc−/−) and their wild type (Hdc+/+) congeners we evaluated if the histaminergic system participates in the protective action of a diet enriched with polyunsaturated fatty acids and vitamin A on the deleterious effect of chronic stress. Behavioural tests across domains relevant to cognition and anxiety were performed. Hippocampal synaptic plasticity, cytokine expression, hippocampal fatty acids, oxylipins and microbiota composition were also assessed. Chronic stress induced social avoidance, poor recognition memory, affected hippocampal long-term potentiation, changed the microbiota profile, brain cytokines, fatty acid and oxylipins composition of both Hdc−/− and Hdc+/+ mice. Dietary enrichment counteracted stress-induced deficits only in Hdc+/+ mice as histamine deficiency prevented almost all the diet-related beneficial effects. Interpretation: Our results reveal a previously unexplored and novel role for brain histamine as a mediator of many favorable effects of the enriched diet. These data present long-reaching perspectives in the field of nutritional neuropsychopharmacology.  相似文献   
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The isolation and identification of intermediates formed in the course of the activation of dioxygen at transition metal centers reveals important mechanistic insights concerning such processes. We previously reported the reaction of the dinuclear CrII complex [L2Cr2(MeCN)2][Li(MeCN)]2 (L=PhSi(OSiPh2O)3) ( 5 ) with dioxygen, which resulted in the formation of the CrIV oxo complex [L2Cr2O2][Li(THF)2]2 ( 6 ), as the final room temperature stable product. Here we now report the isolation and characterization of an intermediate en route to 6 , namely the dinuclear CrIII superoxo complex [L2Cr2(O2)2][Li(MeCN)]2 ( 7 ). 7 is the first example of a structurally characterized dinuclear CrIII superoxo complex with two independent side-on bound superoxo ligands. Reactivity studies outline the capability of this superoxo complex to activate weak O−H bonds.  相似文献   
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There are strong connections between coherent systems in reliability for systems which have components with a finite number of states and certain algebraic structures. A special case is binary systems where there are two states: fail and not fail. The connection relies on an order property in the system and a way of coding states with monomials . The algebraic entities are the Scarf complex and the associated Alexander duality. The failure event can be studied using these ideas and identities and bounds derived when the algebra is combined with probability distributions on the states. The x coding aids the use of moments =E(X ) with respect to the underlying distribution. Keywords:Reliability, Monomial ideals, Scarf complex, Alexander dual, Hilbert series, Moments  相似文献   
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The most familiar emotional signals consist of faces, voices, and whole-body expressions, but so far research on emotions expressed by the whole body is sparse. The authors investigated recognition of whole-body expressions of emotion in three experiments. In the first experiment, participants performed a body expression-matching task. Results indicate good recognition of all emotions, with fear being the hardest to recognize. In the second experiment, two alternative forced choice categorizations of the facial expression of a compound face-body stimulus were strongly influenced by the bodily expression. This effect was a function of the ambiguity of the facial expression. In the third experiment, recognition of emotional tone of voice was similarly influenced by task irrelevant emotional body expressions. Taken together, the findings illustrate the importance of emotional whole-body expressions in communication either when viewed on their own or, as is often the case in realistic circumstances, in combination with facial expressions and emotional voices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Spherical silica supported Hyflon® catalysts (SSHC) were developed to produce ethers from glycerol by etherification reaction with isobutene. SSHC allowed to obtain yields to di- and tri-ethers, suitable as additives or components for diesel fuels, higher than that obtained with A-15 commercial catalyst, and a concentration of undesired mono-ether (not soluble in diesel) lower than 3 wt%. The novel catalysts investigated were found stable and easily reusable; their low acid site density prevented the occurrence of oligomerization reaction accounting for di-isobutene formation. Engine tests performed using a blend containing 10 vol% of glycerol ethers mixture confirmed the positive role of additives in reducing emissions of particulates and unburned hydrocarbons with significant improvement of diesel combustion efficiency.  相似文献   
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Interpretability of Mamdani fuzzy rule-based systems (MFRBSs) has been widely discussed in the last years, especially in the framework of multi-objective evolutionary fuzzy systems (MOEFSs). Here, multi-objective evolutionary algorithms (MOEAs) are applied to generate a set of MFRBSs with different trade-offs between interpretability and accuracy. In MOEFSs interpretability has often been measured in terms of complexity of the rule base and only recently partition integrity has also been considered. In this paper, we introduce a novel index for evaluating the interpretability of MFRBSs, which takes both the rule base complexity and the data base integrity into account. We discuss the use of this index in MOEFSs, which generate MFRBSs by concurrently learning the rule base, the linguistic partition granularities and the membership function parameters during the evolutionary process. The proposed approach has been experimented on six real world regression problems and the results have been compared with those obtained by applying the same MOEA, with only accuracy and complexity of the rule base as objectives. We show that our approach achieves the best trade-offs between interpretability and accuracy.  相似文献   
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