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排序方式: 共有776条查询结果,搜索用时 15 毫秒
41.
Umphress Elizabeth E.; Simmons Aneika L.; Boswell Wendy R.; Triana María del Carmen 《Canadian Metallurgical Quarterly》2008,93(5):982
The authors examined one manner in which to decrease the negative impact of social dominance orientation (SDO), an individual difference variable that indicates support for the "domination of 'inferior' groups by 'superior' groups" (J. Sidanius & F. Pratto, 1999, p. 48), on the selection of candidates from low-status groups within society. Consistent with the tenets of social dominance theory, in 2 studies we found that those high in SDO reported that they were less likely to select a potential team member who is a member of a low-status group (i.e., a White female in Study 1 and a Black male in Study 2) than those low in SDO. However, explicit directives from an authority moderated this effect such that those high in SDO were more likely to select both candidates when authority figures clearly communicated that job performance indicators should be used when choosing team members. Thus, our studies suggest that the negative effects of SDO may be attenuated if those high in SDO are instructed by superiors to use legitimate performance criteria to evaluate job candidates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
S Makino DN Haylock T Dowse S Trimboli S Niutta LB To CA Juttner PJ Simmons 《Canadian Metallurgical Quarterly》1997,6(5):475-489
A major potential application for ex vivo culture of hematopoietic progenitor cells is the treatment of cytopenia following high-dose chemotherapy and hematopoietic transplantation. We have previously postulated that infusion of a sufficient number of neutrophil postprogenitor cells generated by ex vivo culture of CD34+ cells may be able to abrogate neutropenia. In this article, we describe further development of an efficient stromal-free, cytokine-dependent, static culture system for generation of these cells. Our previous studies indicated that maximal production of nucleated cells and myeloid progenitor cells from PB CD34+ cells occurred with multiple hematopoietic growth factor (HGF), notably the 6-HGF combination of interleukin (IL)-1, IL-3, IL-6, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), and stem cell factor (SCF). In the present study, we determine the contribution of each of these 6 HGF in generation of neutrophilic precursors. SCF, G-CSF, and IL-3 were found to be the most important HGF for production of neutrophilic cells. The 4-HGF combination of IL-3, IL-6, G-CSF, and SCF was optimized by performing dose-response experiments and shown to be as potent as 6 HGF for production of nascent CFU-GM and neutrophilic precursors. 相似文献
43.
Daryl M. Simmons Glenn D. Portmann Andrew B. C. Yu Jon R. Swanson 《Drug development and industrial pharmacy》1997,23(8):783-789
WIN 63843, a Picornavirus replication inhibitor, is physically and chemically stable in the solid state, to light, elevated temperature, and humidity. This 3-ary15-trifluoromethyl disubstituted 1,2,4-oxadiazole compound has very low water solubility but is highly soluble in ethanol and in safflower seed and corn oils. Solubility in the vegetable oils is doubled by the synergistic effect of ethanol at the 16% alcohol concentration. Vegetuble oil solutions of WIN 63843 are thermally stable but react slowly in the presence of light resulting in an amidoxime compound (WIN 65489) formed by opening of the 1,2,4-oxadiazole ring. This reaction does not occur in oil solutions containing small concentrations of ethanol. Of biophannaceutical interest, the addition of ethanol or PEG-400 solutions of WIN 63843 to human gastric fluid resulted in oily droplet formation whereas crystals form upon addition of these solutions to water. Also, the compound is greater than 8,000 times more soluble in human gastric fluid. 相似文献
44.
The production of a polymer containing basic functional groups via the reactive processing of polyethylene was investigated. Grafting of dimethylamino ethyl methacrylate, DMAEMA, to linear low-density polyethylene in the melt was carried out, and the effects of initiator type, feed composition, and reaction time and temperature were studied. The extent of grafting was determined by Fourier transform infrared and 1H nuclear magnetic resonance spectroscopy, and the degree of cross-linking was observed by measuring the products' melt indices. Thermal stability of the product was investigated using differential scanning calorimetry. Materials containing up to 3 wt% of grafted DMAEMA were prepared. The choice of appropriate feed compositions and reaction conditions allows the production of a material containing the maximum amount of grafted DMAEMA, while minimizing cross-linking. The grafted polyethylene produced under these conditions is more stable than the starting material, suggesting an antioxidant effect of the grafted moieties. The functional polymer produced should be of interest for the preparation of polymer blends with acidic polymers by virtue of the miscibility enhancement that could occur as compared with the hydrocarbon precursor. 相似文献
45.
Taylor G.W. Lebby M.S. Chang T.Y. Gnall R.N. Sauer N. Tell B. Simmons J.G. 《Electronics letters》1987,23(2):77-79
A new form of FET has been demonstrated in the GaAs/AlGaAs material system. Designated the HFET, it has shown a transconductance of 500mS/mm at 300K for a nominal Lg =2?m and a drain current of 430mA/mm. The conduction occurs in an inversion channel at the heterointerface. 相似文献
46.
A complementary inverter configuration based on two new heterostructure field-effect devices is proposed. The FETs are fabricated in a common substrate grown by molecular-beam epitaxy. The devices rely on the formation of inversion layers at heterojunction interfaces. 相似文献
47.
Robert Simmons 《中国橡胶》2010,26(2):13-16
一、全球轮胎市场发展趋势
对于轻型汽车(LV,包括轿车胎和轻型商用车胎)和中重型载重卡车(M/H CV)来说,国内生产总值(GDP)的增长是其需求增长的动力。金融危机和经济衰退使欧美等发达国家GDP减少.导致全球轮胎销售额的大幅下降,其中原配轮胎(OE)市场受到的影响更为严重。通常,中重型载重卡车轮胎中,原配胎销售额占其总销售额的20%;轻型汽车轮胎中,原配胎占25%。 相似文献
48.
Krometis LA Characklis GW Simmons OD Dilts MJ Likirdopulos CA Sobsey MD 《Water research》2007,41(2):506-516
Association with particles in the water column can have a significant impact on microbial fate and transport. This study analyzed multiple stormwater samples taken throughout the duration of three separate storms (at two different sites) to evaluate the fraction of microbes partitioning to denser "settleable" particles and to examine how partitioning behavior varied over the course of a storm. Intra-storm sampling also allowed for estimates of microbial loading rates (both total and particle-associated) and cumulative storm-induced microbial load. Five different indicator organisms were examined, with the fraction of microbes associated with settleable particles assessed via a calibrated centrifugation method. Partitioning behavior varied across microorganism type, with an average of 40% of fecal coliforms, Escherichia coli, and enterococci associating with settleable particles, compared to approximately 65% of Clostridium perfringens spores and only 13% of total coliphage. Partitioning remained fairly constant for each type of organism throughout storm events. Nonetheless, higher concentrations of both settleable particles and microbes entering the water column soon after the onset of a storm led to higher loading rates of settleable microbes in the storm's earliest stages, a trend that could have important implications for the design of stormwater management structures (e.g., detention basins). Estimates of cumulative storm-induced microbial loading suggested that one day's worth of storm loading can be the equivalent of months, or even years, of dry-weather loading. 相似文献
49.
Effects of Microbial Transglutaminase on the Wheat Proteins of Bread and Croissant Dough 总被引:6,自引:0,他引:6
J.A. Gerrard S.E. Fayle P.A. Brown K.H. Sutton L. Simmons I. Rasiah 《Journal of food science》2001,66(6):782-786
ABSTRACT: Transglutaminase is a crosslinking enzyme that is finding increasing use in foods, yet the molecular changes responsible for its effects are not fully understood. Proteins were extracted from bread and croissant doughs that had been treated with transglutaminase and compared to those from control doughs by size exclusion high performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. Transglutaminase increased the amount of protein extracted in the gliadin fraction in both bread and croissant doughs. In croissant doughs, a corresponding decrease in the protein extracted in the albumin to globulin fraction was seen. In each case, crosslinking of the high molecular weight glutenins was observed. The possible role of each of these changes on the functional properties of baked products is discussed. 相似文献
50.
Journal bearings are an important design option, particularly appropriate for high-speed rotating machinery applications. This paper presents results from an extensive program of experimental work with a 200 mm, five-shoe, tilting-pad bearing of this type. The tilting pads were fitted with offset pivots; this is in contrast to most previous work which has concentrated on bearings with pads which have centrally mounted pivots. The new results obtained for the offset pivot pad bearing are compared with recently published, equivalent results for the same bearing filled with center pivot pads. A substantial temperature reduction in bearing temperature is revealed for the offset pivot case. 相似文献