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41.
由贵州大学计算机科学与信息学院主办的“国际逻辑会议LOGIC2009”于2009年9月22日在贵州大学南校区南园接待中心隆重召开。20多位逻辑学家、数学家和计算机科学家参加了会议,他们分别来自贵州大学、贵州民族学院、新加坡国立大学、中国科学院、北京师范大学、四川大学、南开大学、南京大学、 相似文献
42.
为研究盐酸戊乙奎醚对心脏瓣膜置换术患者心肌NF-κB转录活性的影响,选取择期瓣膜置换术患者60例,随机分为对照组(C)、盐酸戊乙奎醚组1(P1)、盐酸戊乙奎醚组2(P2),每组20例。结果心肌缺血再灌注后,P1、P2组NF-κB的转录活性明显下降,可见盐酸戊乙奎醚可以抑制心肌NF-κB的激活,在一定程度上具有心肌保护作用。 相似文献
43.
Bennett J. Tepper Jon C. Carr Denise M. Breaux Sharon Geider Changya Hu Wei Hua 《Organizational behavior and human decision processes》2009,109(2):156-167
We conducted a two-study examination of relationships between abusive supervision and subordinates’ workplace deviance. Consistent with predictions derived from power/dependence theory, the results of a cross-sectional study with employees from three organizations suggest that abusive supervision is more strongly associated with subordinates’ organization deviance and supervisor-directed deviance when subordinates’ intention to quit is higher. The results also support the prediction that when intention to quit is higher, abusive supervision is more strongly associated with supervisor-directed deviance than with organization-directed deviance. These results were replicated in a second study, a two-wave investigation of people employed in a variety of industries and occupations. 相似文献
44.
Brona S. O'dowd Wei Q. Zhao Kim T. Ng Stephen R. Robinson 《Neurobiology of learning and memory》1997,67(3):197-206
The cellular expression of S-100β protein is upregulated in Alzheimer's disease and in Down's syndrome, and this protein has been implicated in memory-related processes in laboratory animals. However, the possibility that the α subunit of S-100 is also involved in memory has not yet been examined. In the present study, day-old black Australorp white Leghorn cockerel chicks (Gallus domesticus) received injections of monoclonal antisera to S-100α (1:50) or S-100β (1:500) into each hemisphere immediately after training on a one-trial passive avoidance task. The chicks displayed significantly lower retention levels than control birds that had been injected with antisera to carbonic anhydrase, or with saline (p< .01). S-100α antisera had an amnestic effect when injected between 0 and 20 min after training, with memory deficits occurring from 30 min postlearning, at the point of transition between the A and the B phases of the Gibbs-Ng intermediate memory stage. By contrast, the S-100β antisera needed to be injected either 5 min before or immediately after training and produced amnesia 10 min earlier, at the start of the A phase of the intermediate memory stage. We conclude that the two subunits of the S-100 protein are required at different points in the sequence of events leading to the consolidation of passive avoidance memory. 相似文献
45.
The present study examined the effects of orthographic neighborhood (N) size on the cognitive processes underlying Chinese character reading. Previous research has shown increasing N size facilitates word naming and recognition performance in alphabetic languages. Experiment 1 revealed that a large N size was associated with a general inhibition of processes underlying character reading, in contrast to previous findings with alphabetic languages. This inhibitory effect was influenced by regularity and consistency. Experiment 2 sought to assess the effects of higher-frequency neighbors on character naming performance. The results revealed that higher-frequency neighbors with different pronunciation to the target interfered with the phonological retrieval of targets. We propose that this type of interference may have caused the N size effect observed in Experiment 1. The results of Experiment 3 revealed that a large N size facilitated target naming in the absence of higher-frequency neighbors. The current results shed light on the processes underlying character naming, and we propose possible cognitive mechanisms of the N size effect on Chinese character naming. 相似文献
46.
There is considerable evidence that, when recalling past events, Westerners exhibit greater episodic specificity than East Asians and women exhibit greater episodic specificity than men. Yet it is unknown whether the same cultural and gender differences are true for future events. In the present study 209 European American and Chinese young adults were asked to recall past personal events and imagine future personal events occurring in varied time periods (i.e., 1 week, 1 year, 10-15 years). Regardless of time period, European Americans consistently produced more specific details than Chinese for future events than they did for past events, and women produced more specific details than men for both past and future events. These findings provide additional support for the constructive-episodic-simulation hypothesis, and shed new light on the influence of culture and gender on episodic thinking. 相似文献
47.
48.
Jiin‐Huarng Guo Hubert J. Chen Wei‐Ming Luh 《The British journal of mathematical and statistical psychology》2011,64(3):439-461
The allocation of sufficient participants into different experimental groups for various research purposes under given constraints is an important practical problem faced by researchers. We address the problem of sample size determination between two independent groups for unequal and/or unknown variances when both the power and the differential cost are taken into consideration. We apply the well‐known Welch approximate test to derive various sample size allocation ratios by minimizing the total cost or, equivalently, maximizing the statistical power. Two types of hypotheses including superiority/non‐inferiority and equivalence of two means are each considered in the process of sample size planning. A simulation study is carried out and the proposed method is validated in terms of Type I error rate and statistical power. As a result, the simulation study reveals that the proposed sample size formulas are very satisfactory under various variances and sample size allocation ratios. Finally, a flowchart, tables, and figures of several sample size allocations are presented for practical reference. 相似文献
49.
在现代社会中,公共性、开放性已成为现代图书馆的本质属性.和前现代社会相比,现代图书馆所承担的社会伦理责任也已经发生了深刻变化,它已不再是单纯地储存图书资料并仅仅面向精英阶层的场所,而是成为了面向社会公众,承担着促进国民素质提高、实践共同价值、传承人类文化、促进社会和谐等伦理责任的知识殿堂. 相似文献
50.
Four studies were conducted to develop and validate the Coping With Discrimination Scale (CDS). In Study 1, an exploratory factor analysis (N = 328) identified 5 factors: Education/Advocacy, Internalization, Drug and Alcohol Use, Resistance, and Detachment, with internal consistency reliability estimates ranging from .72 to .90. In Study 2, a confirmatory factor analysis (N = 328) provided cross-validation of the 5-factor model as well as evidence for validity of the scale. The validity evidence was similar across racial groups and for males and females. In Study 3, the estimated 2-week test-retest reliabilities (N = 53) were between .48 and .85 for the 5 factors. Education/Advocacy, Internalization, Drug and Alcohol Use, and Detachment were positively associated with active coping, self-blame, substance use, and behavioral disengagement, respectively, providing further support for validity of the CDS. Finally, incremental validity evidence was obtained in Study 4 (N = 220), where it was shown that the CDS explained variance in outcome variables (i.e., depression, life satisfaction, self-esteem, and ethnic identity) that could not be explained by general coping strategies. 相似文献