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11.
This study evaluates the role of partial coalescence of whey protein-stabilized emulsions on sensory perception. The selection of fats was restricted to vegetable fats that are essentially melted at oral temperatures. The sensitivity to partial coalescence was controlled by a variation in the fat melting curve and by addition of unsaturated monoglyceride. Most fat-related sensory attributes appear to be well-correlated to an increase in viscosity and coalescence in the mouth due to partial coalescence. Moreover, it was found that in-mouth aeration induces extra coalescence, which increases the perception of fat-related sensory attributes significantly.  相似文献   
12.
The Asian tiger mosquito (Aedes albopictus) is an invasive species that has the potential to transmit infectious diseases such as dengue and chikungunya fever. Using high-resolution observations and regional climate model scenarios for the future, we investigated the suitability of Europe for A. albopictus using both recent climate and future climate conditions. The results show that southern France, northern Italy, the northern coast of Spain, the eastern coast of the Adriatic Sea and western Turkey were climatically suitable areas for the establishment of the mosquito during the 1960–1980s. Over the last two decades, climate conditions have become more suitable for the mosquito over central northwestern Europe (Benelux, western Germany) and the Balkans, while they have become less suitable over southern Spain. Similar trends are likely in the future, with an increased risk simulated over northern Europe and slightly decreased risk over southern Europe. These distribution shifts are related to wetter and warmer conditions favouring the overwintering of A. albopictus in the north, and drier and warmer summers that might limit its southward expansion.  相似文献   
13.
Different approaches to study wetting and adhesion by applying density-functional theory (DFT) methods are highlighted. The ab initio thermodynamics method is used to demonstrate the link between the calculated work of separation and the work of adhesion and wetting angles from sessile-drop measurements. An approach to extend DFT calculations to the case of large-scale interfaces relevant for wetting systems is also discussed.  相似文献   
14.
Reduced autobiographical memory (AM) specificity is a known vulnerability factor for depression. AM specificity was investigated as a predictor of depression with the Autobiographical Memory Test (J. M. G. Williams & K. Broadbent, 1986). When baseline depression scores were partialed, reduced AM specificity to negative cue words predicted higher levels of depression at 7-month follow-up. Once rumination was taken into account by means of the Rumination on Sadness Scale (M. Conway, P. A. R. Csank, S. L. Holm, & C. K. Blake, 2000), AM specificity no longer predicted depression, suggesting that the predictive value of AM specificity observed in previous studies might be--at least partly--explained as an effect of rumination. Further mediation analyses indeed revealed support for rumination as a mediator of the relation between reduced AM specificity and poor outcome of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
After rearrangement of the T-cell receptor (TCR) beta-locus, early CD4(-)/CD8(-) double negative (DN) thymic T-cells undergo a process termed 'beta-selection' that allows the preferential expansion of cells with a functional TCR beta-chain. This process leads to the formation of a rapidly cycling subset of DN cells that subsequently develop into CD4(+)/CD8(+) double positive (DP) cells. Using transgenic mice that constitutively express the zinc finger protein Gfi-1 and the serine/threonine kinase Pim-1, we found that the levels of both proteins are important for the correct development of DP cells from DN precursors at the stage where 'beta-selection' occurs. Analysis of the CD25(+)/CD44(-,lo) DN subpopulation from these animals revealed that Gfi-1 inhibits and Pim-1 promotes the development of larger beta-selected cycling cells ('L subset') from smaller resting cells ('E subset') within this subpopulation. We conclude from our data that both proteins, Pim-1 and Gfi-1, participate in the regulation of beta-selection-associated pre-T-cell differentiation in opposite directions and that the ratio of both proteins is important for pre-T-cells to pass the 'E' to 'L' transition correctly during beta-selection.  相似文献   
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BenvanBerkel曾就读于阿姆斯特丹Rietveld学院和伦敦建筑协会建筑学院(AA)。1988年.他和艺术历史学家CarolineBos共同创立了UNStudio。1996年。他参与鹿特丹知名的伊拉斯谟大桥的外形设计。这深刻地影响了他对当代建筑的理解.从而形成自己独具一格的风格。亦成为UNStudio营运理念的基础。BenvanBerkeI在许多知名的大学担任过客座讲师。与他人合作撰写了大量论文和专著。BenvanBerkel目前是德国法兰克福StaedeIschule概念设计系的教授和建筑学院院长。而他在中国的第一个项目,已开始在杭州建设。  相似文献   
18.
We here show that anergic T cells are active mediators of T cell suppression. In co-culture experiments, we found that anergic T cells, derived from established rat T cell clones and rendered anergic via T cell presentation of the specific antigen (Ag), were active inhibitors of T cell responses. Anergic T cells inhibited not only the responses of T cells with the same Ag specificity as the anergic T cells, but were also capable of efficiently inhibiting polyclonal T cell responses directed to other epitopes. This suppression required close cell-cell contact between antigen-presenting cells (APC), anergic T cells and responder T cells, and only occurred when the epitope recognized by the anergic T cell was present. The suppression was not caused by passive competition for ligands on the APC surface, IL-2 consumption, or cytolysis, and was not mediated by soluble factors derived from anergic T cells that were stimulated with their specific Ag. When responder T cells were added 24 h after co-culturing anergic cells in the presence of Ag and APC, T cell responses were still suppressed, indicating that the suppressive effect was persistently present. However, anergic T cells were not able to suppress responder T cells that had already received a full activation signal. We propose that suppression by anergic T cells is mediated via the APC, either through modulation of the T cell-activating capacity of the APC (APC/T cell interaction), or by inhibition of T cells recognizing their ligand in close proximity on the same APC (T/T cell interaction).  相似文献   
19.
The gfi-1 gene encodes a zinc finger containing protein that is specifically expressed in T-lymphocytes and is a frequent target of proviral insertion in T-cell lymphoma provoked by infection with MoMuLV--a non acute transforming retrovirus. Expression of a gfi-1 transgene targeted to T-cells by the lck proximal promoter provokes a reduction of peripheral CD4 and CD8 positive T-cells but nevertheless weakly predisposes transgenic animals for the development of T-cell lymphoma. Forced coexpression of the serine/threonine kinase Pim-1 can partially restore normal T-cell numbers in double pim-1/gfi-1 transgenic mice. Moreover, the combinatorial expression of Pim-1 and Gfi-1 leads to accelerated development of T-cell lymphoma with a mean latency period of 114 days. A similar accelerated rate of lymphoma development was observed when lck-gfi-1 mice were crossed with mice that carry a L-myc gene targeted to be expressed at high levels in T-cells. The results show that gfi-1 can act with low activity as a dominant oncogene when overexpressed but also demonstrate that it is most efficient only in the presence of a cooperative partner protein as for example Pim-1 or L-Myc. In addition, the results suggest that Pim-1 and Gfi-1 are acting synergistically in both T-cell lymphomagenesis and T-cell development.  相似文献   
20.
The Wertheim lattice thermodynamic perturbation theory is used to predict the liquid-liquid and solid-liquid coexistence data for a model polymer solution. The theory predicts bimodal LCST phase behavior and an unusual step with composition in the solid-liquid equilibrium of the solvent.The theoretical solid-liquid equilibrium calculations are used to interpret experimental data obtained for aqueous solutions of poly(vinyl methyl ether) (PVME), which is known to show bimodal LCST phase behavior. An experimental method is proposed, employing Fourier transform infrared (FTIR) spectroscopy to determine the equilibrium melting line of water in the presence of PVME. In addition, the complete melting line of water is obtained by partial integration of the melting endotherm observed using modulated temperature differential scanning calorimetry (MTDSC). Both, the FTIR and MTDSC methods are in good agreement, experimentally confirming the predicted step with composition in the solid-liquid equilibrium. This peculiar concentration dependence of the melting curve of ice provides a new explanation for the inhibited crystallization of water in aqueous PVME solutions, since the actual supercooling (at high polymer concentration) is smaller than it could be anticipated for a conventional course of the melting curve. Hence, the vicinity of the glass transition region in these highly concentrated polymer mixtures leads to a dramatic slowing down of the nucleation rate and thus the subsequent crystallization. Moreover, the atypical shape of the equilibrium melting line also provides a new explanation for the double melting endotherm observed in (MT)DSC experiments, which is conventionally attributed to the melting at different temperatures of bound and free water.  相似文献   
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