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排序方式: 共有334条查询结果,搜索用时 15 毫秒
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Pauker Kristin; Weisbuch Max; Ambady Nalini; Sommers Samuel R.; Adams Reginald B. Jr.; Ivcevic Zorana 《Canadian Metallurgical Quarterly》2009,96(4):795
Exponential increases in multiracial identities, expected over the next century, create a conundrum for perceivers accustomed to classifying people as their own- or other-race. The current research examines how perceivers resolve this dilemma with regard to the own-race bias. The authors hypothesized that perceivers are not motivated to include ambiguous-race individuals in the in-group and therefore have some difficulty remembering these individuals. Both racially ambiguous and other-race faces were misremembered more often than own-race faces (Study 1), though memory for ambiguous faces was improved among perceivers motivated to include biracial individuals in the in-group (Study 2). Racial labels assigned to racially ambiguous faces determined memory for these faces, suggesting that uncertainty provides the motivational context for discounting ambiguous faces in memory (Study 3). Finally, an inclusion motivation fostered cognitive associations between racially ambiguous faces and the in-group. Moreover, the extent to which perceivers associated racially ambiguous faces with the in-group predicted memory for ambiguous faces and accounted for the impact of motivation on memory (Study 4). Thus, memory for biracial individuals seems to involve a flexible person construal process shaped by motivational factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Stevenson DE Cooney JM Jensen DJ Zhang J Wibisono R 《Molecular nutrition & food research》2007,51(8):939-945
To simulate the effects of digestion and metabolism on the survival of different polyphenolic compounds, extracts of blueberry and apple were deglycosylated by acid hydrolysis, followed by enzymic glucuronidation under neutral conditions, yielding approximately 5% overall recovery of polyphenolics. The major polyphenolics before and after the treatment were compared, to estimate which species are likely to be present in the intestinal lumen, undegraded and available for absorption, after consumption of the fruit. Whereas blueberry extract consisted predominantly of anthocyanins, epicatechin and caffeoyl quinate esters, the major components of the treated extract were quercetin glucuronides and (unglucuronidated) caffeoyl quinates, with only traces of anthocyanidin derivatives. In apple extract, compositional changes were less marked, but caffeoyl quinates, procyanidins and quercetin were enriched at the expense of caffeic acid, epicatechin and catechin. Hydrophobic compounds like phloretin and quercetin were extensively glucuronidated, whereas caffeic acid and caffeoyl quinate were not. These results suggest that the major polyphenolic components of a fruit are not necessarily the most important contributors to any health benefits because the polyphenolic composition in the intestinal lumen and consequently, in the circulation, may be considerably different. 相似文献
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This article offers a unique three-stage approach in LCI analysis for generating the environmental profile of electricity generation in Singapore. The first stage focuses on fuels delivered to Singapore, next on electricity generated from various types of power production plants. The third stage integrates the entire life cycle study. The final gate-to-gate results show that the total CO2 emissions from the national grid are 455.6 kg CO2 per MWh without any loss in transmission and 467.0 kg CO2 per MWh with 2.5% losses. The results for the entire cradle-to-gate energy production are: 586.3 kg CO2 per MWh without considering any losses and 601.0 kg CO2 per MWh with 2.5% transmission loss. For the rest of the LCI, the cradle-to-gate results (per MWh) are kg 0.19 CO (carbon monoxide), 0.06 kg N2O (nitrous oxide), 1.94–1.99 kg NOx (nitrogen oxides), 2.94–3.01 kg SOx (sulphur oxides), 0.064–0.066 kg VOC (volatile organic compounds) and 0.078–0.080 kg PM (particulate matters). From gate-to-gate, the results are 0.12 kg CO, 0.0016 kg N2O, 1.42–1.46 kg NOx, 2.56–2.62 kg SOx, 0.033–0.034 kg VOC and 0.067–0.069 kg PM. Emissions of CO2 from energy generation, climate change mitigation and policies for energy security are also discussed. 相似文献
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David Veneziano Shauna Hallmark & Reginald Souleyrette 《Computer-Aided Civil and Infrastructure Engineering》2004,19(2):130-143
Abstract: Surface terrain information is required to economically site new or relocate existing infrastructure facilities and make final design plans. Currently, ground surveying and photogrammetric mapping are the methods used by Departments of Transportation (DOTs) to acquire these data. Both the methods are time and resource intensive as they require significant data collection and reduction to provide the level of detail necessary for facility location. Additionally, conventional surveying entails data collection entirely in the field and may require personnel to be located on or near heavily traveled roadways. The research presented compares surface elevation data from Light Detection and Ranging (LIDAR) to that obtained from traditional photogrammetry and Global Positioning System (GPS) data collection for use in highway location and design. A pilot area previously mapped by the Iowa Department of Transportation was selected for evaluation. A comparison of the elevational accuracy and data quality of LIDAR with respect to two comparable collection methods is presented . 相似文献
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Strong earthquakes can result in large longitudinal displacements in multiple-frame bridges. This could lead to excessive displacements/openings at the intermediate joints. Bridges with small seat widths are vulnerable to the unseating of their superstructure. Seismic steel restrainers are currently used to limit the joint openings in bridges. However, past earthquakes have shown that restrainer cables have limitations in regards to preventing unseating in bridges. Other devices have been proposed to limit joint displacements, including metallic dampers, viscoelastic dampers, and shape memory alloys (SMAs), which are known for their ability to recover their original shape after being deformed. A sensitivity study and a case study are conducted using computer simulations to compare the effectiveness of SMA retrofit devices with other devices. The results show that the effectiveness of the devices is a function of the characteristics of the bridge frames and the ground motion characteristics. In all cases, the steel restrainer cables were the least effective in limiting joint displacements. The SMA devices have the additional benefit of significantly limiting the residual joint displacement in bridges. 相似文献
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Jason McCormick Jeff Tyber Reginald DesRoches Ken Gall Hans J. Maier 《Canadian Metallurgical Quarterly》2007,133(9):1019-1029
This paper continues to address the overarching goal to provide a more unified understanding of NiTi shape memory alloys intended for use in structural applications by attempting to link standard processing practice and basic materials characterization to the deformation behavior of large diameter bars. Results from cyclic tensile tests performed on large diameter Ni-rich polycrystalline NiTi bars are presented. Coupon specimens taken from deformation processed bars with diameters of 12.7, 19.1, and 31.8?mm are tested along with their respective full-scale specimens. The coupon tests results reveal small and highly variable differences between specimens taken from the different size bars. The full-scale specimen tests continue to show the presence of the R phase, but lack a Lüders-like transformation. A comparison of the results suggests that coupon specimens provide only limited information in terms of the full-scale behavior. Full-scale tests using an earthquake-type loading then show similar behavior to the tensile cyclic tests suggesting the ability to use NiTi in structural applications. Overall, this paper and Tyber et al. 2007 provide a multiscale analysis of NiTi shape memory alloys to be used by both material scientist and civil engineers in the development of applications for NiTi. 相似文献
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