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191.
192.
Robin Carr D. H. Thomas T. S. Venkataraman Allan L. Smith Michael A. Gealt R. Quinn M. Tanyel 《工程教育杂志》1995,84(2):137-150
All fields of engineering, whether chemical, civil, electrical, materials, mechanical, etc., encompass a common body of essential mathematics and science. In the freshman year of Drexels E4 program, this common mathematical and scientific foundation is cultivated in the Mathematical and Scientific Foundations of Engineering I, II and III (MSFE I, MSFE II, MSFE III). In an integrated fashion, MSFE I presents the essential calculus, physics and engineering mechanics vital to the freshman engineering student. In the first two quarters, MSFE II presents chemistry with clearly defined engineering applications and significance: in the third quarter, MSFE II presents living systems with the same thrust. Also in the third quarter, MSFE III presents basic circuits and circuit elements, and a brief introduction to electromagnetic theory. 相似文献
193.
JB Thomas MJ Fall JB Cooper RB Rothman SW Mascarella H Xu JS Partilla CM Dersch KB McCullough BE Cantrell DM Zimmerman FI Carroll 《Canadian Metallurgical Quarterly》1998,41(26):5188-5197
A three-component library of compounds was prepared in parallel using multiple simultaneous solution-phase synthetic methodology. The compounds were biased toward opioid receptor antagonist activity by incorporating (+)-(3R,4R)-dimethyl-4-(3-hydroxyphenyl)piperidine (a potent, nonselective opioid pure antagonist) as one of the monomers. The other two monomers, which included N-substituted or unsubstituted Boc-protected amino acids and a range of substituted aryl carboxylic acids, were selected to add chemical diversity. Screening of these compounds in competitive binding experiments with the kappa opioid receptor selective ligand [3H]U69,593 led to the discovery of a novel kappa opioid receptor selective ligand, N-?(2'S)-[3-(4-hydroxyphenyl)propanamido]-3'-methylbutyl?-(3R, 4R)-dimethyl-4-(3-hydroxyphenyl)piperidine (8, RTI-5989-29). Additional structure-activity relationship studies suggested that 8 possesses lipophilic and hydrogen-bonding sites that are important to its opioid receptor potency and selectivity. These sites appear to exist predominantly within the kappa receptor since the selectivity arises from a 530-fold loss of affinity of 8 for the mu receptor and an 18-fold increase in affinity for the kappa receptor relative to the mu-selective ligand, (+)-N-[trans-4-phenyl-2-butenyl]-(3R, 4R)-dimethyl-4-(3-hydroxyphenyl)piperidine (5a). The degree of selectivity observed in the radioligand binding experiments was not observed in the functional assay. According to its ability to inhibit agonist stimulated binding of [35S]GTPgammaS at all three opioid receptors, compound 8 behaves as a mu/kappa opioid receptor pure antagonist with negligible affinity for the delta receptor. 相似文献
194.
Kleinke Chris L.; Peterson Thomas R.; Rutledge Thomas R. 《Canadian Metallurgical Quarterly》1998,74(1):272
Two experiments were conducted in which participants looked at photographs (Experiment 1, n?=?129) or slides (Experiment 2, n?=?90) of people engaging in positive or negative facial expressions. Participants attempted to communicate these facial expressions as accurately as they could to a video camera while viewing themselves in a mirror or without viewing themselves in a mirror. Participants in a control group maintained neutral facial expressions. Participants experienced increased positive moods when they engaged in positive facial expressions and decreased positive moods when they engaged in negative facial expressions. These effects were enhanced when participants viewed themselves in a mirror. The effects of facial expressions on positive affect were stronger for participants with high private self-consciousness. Results were integrated with research identifying individuals who are responsive to self-produced versus situational cues and with theory and research on self-awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
195.
Based on a rearrangement inequality by Hardy, Littlewood, and Polya, we define two-operator algebras for independent random variables. These algebras are called Huffman algebras since the Huffman algorithm on these algebras produces an optimal binary tree that minimizes the weighted lengths of leaves. Many examples of such algebras are given. For the case with random weights of the leaves, we prove the optimality of the tree constructed by the power-of-2 rule, i.e., the Huffman algorithm assuming identical weights, when the weights of the leaves are independent and identically distributed. 相似文献
196.
197.
Thomas Emery 《Journal of population ageing》2012,5(1):7-22
The anticipated, dramatic shift in the demographics of European societies over the next half a century begs many questions about the state of relations between generations. Papers and speculations portraying a world in which the elderly rule through parliamentary majorities, preventing reductions in pensions and ??enslaving?? the working population are surprisingly common. Existing literature on these hypotheses focus on the policy preference differences between the young and the old with evidence mixed as to the accuracy of these predictions. This paper aims to build on this debate by looking at the effects that the dependency ratio has on intergenerational relations. By using a multilevel methodology and data from the 2008 European Social Survey, the effect of demographic structure can be observed on the individual level. Yet whilst evidence is found of decreasing legitimacy of welfare for the elderly, this paper argues that this does not point to increasing intergenerational conflict in Europe. 相似文献
198.
K. Srikrishna G. Thomas R. Martinez M. P. Corral S. De Aza J. S. Moya 《Journal of Materials Science》1990,25(1):607-612
The kaolinite-mullite reaction series in single crystal kaolinite has been characterized by transmission electron microscopy. The exotherm observed at 980° C is attributed to the formation of a spinel phase. Mullite crystallites have also been observed with the spinel phase and both phases have a composition near that of 32 mullite. Subsequent heat treatment leads to the growth of mullite crystallites on the original kaolinite plates with the c-axis perpendicular to the plate. 相似文献
199.
200.
Kalinnik Natalia Kiesel Robert Rauber Thomas Richter Marcel Rünger Gudula 《The Journal of supercomputing》2021,77(4):3484-3515
The Journal of Supercomputing - Scientific application codes are often long-running time- and energy-consuming parallel codes, and the tuning of these methods towards the characteristics of a... 相似文献