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101.
A review is presented of the gaseous combustion and pyrolysis products evolved from coal, wood and PVC. Information has been collated on the range of products evolved, the temperatures of evolution and the effect of different ambient conditions (e.g. oxidizing of inert conditions). The data for coal have been subdivided into those from which rates of gas evolution have been or can be derived and those from which this is not possible. Probable decomposition routes for PVC and for wood are discussed. Although all three materials have been widely studied, the correlation between the work of different authors in not always good. The data obtained are dependent on the form of the experiment, and there are gaps in the information available, especially information on the rates of evolution of products of products as a function of temperature. 相似文献
102.
In this study, the authors linked core self-evaluations to job and work success. Utilizing a dynamic design from participants in the National Longitudinal Surveys of Youth (NLSY79), core self-evaluations were hypothesized to predict individuals' intercepts (starting levels of success), and their growth trajectories (slope of individuals' success over time) with respect to job satisfaction, pay, and occupational status. Results indicated that higher core self-evaluations were associated with both higher initial levels of work success and steeper work success trajectories. Education and health problems that interfere with work mediated a portion of the hypothesized relationships, suggesting that individuals with high core self-evaluations have more ascendant jobs and careers, in part, because they are more apt to pursue further education and maintain better health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Protein structure alignment by incremental combinatorial extension (CE) of the optimal path 总被引:19,自引:0,他引:19
A new algorithm is reported which builds an alignment between two protein
structures. The algorithm involves a combinatorial extension (CE) of an
alignment path defined by aligned fragment pairs (AFPs) rather than the
more conventional techniques using dynamic programming and Monte Carlo
optimization. AFPs, as the name suggests, are pairs of fragments, one from
each protein, which confer structure similarity. AFPs are based on local
geometry, rather than global features such as orientation of secondary
structures and overall topology. Combinations of AFPs that represent
possible continuous alignment paths are selectively extended or discarded
thereby leading to a single optimal alignment. The algorithm is fast and
accurate in finding an optimal structure alignment and hence suitable for
database scanning and detailed analysis of large protein families. The
method has been tested and compared with results from Dali and VAST using a
representative sample of similar structures. Several new structural
similarities not detected by these other methods are reported. Specific
one-on-one alignments and searches against all structures as found in the
Protein Data Bank (PDB) can be performed via the Web at
http://cl.sdsc.edu/ce.html.
相似文献
104.
105.
Ibrahim Burki Cristian Rivas Jeff Hurst Matt Weldon Henry Yeung Jimmy Price Patrick Lysaght P.Y.Hung Raj Jammy 《集成电路应用》2008,(7):36-38
量测平台的复杂性和光学原理上的局限性制约着测量系统的应用,直到真空紫外光谱反射仪的出现,这种状况才得到改变。 相似文献
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107.
X-linked inhibitor of apoptosis protein (XIAP) interacts with caspases to inhibit their activity, thereby providing a potential mechanism for regulation of granulosa cell apoptosis occurring during follicular atresia. The aim of this study was to determine the presence and localization of XIAP mRNA and protein content in the sheep ovary and compare these expression patterns with active caspase-3 protein in the same antral follicles. Romney ewe estrous cycles (n=25) were synchronized with 2-3 Estrumate injections and ovarian tissue collected during the luteal and follicular phases of the cycle. The presence of XIAP mRNA was confirmed by RT-PCR using laser capture microdissected ovarian cell samples. XIAP mRNA was subsequently localized by in situ hybridization histochemistry and XIAP and active caspase-3 protein visualized by immunohistochemistry. In antral follicles extensive XIAP localization was evident in both granulosa and thecal cells. In contrast, mRNA expression was widespread in granulosa cells and only detected in thecal tissue from a small proportion of antral follicles. Active caspase-3 and XIAP comparative expression analysis showed positive XIAP mRNA expression in all late luteal phase (day 14) follicles, despite varying levels of active caspase-3 protein. A proportion of follicular phase (days 15 and 16) follicles, however, showed an inverse expression relationship at the protein and mRNA levels in both granulosa and thecal tissue, as did XIAP protein in day 14 follicles. These results suggest high XIAP may prevent activation of caspase-3, thereby regulating follicular atresia in antral follicles and could potentially be utilized as a marker of follicular health. 相似文献
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