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151.
为了深入了解当代大学生的创业意向及其影响因素,研究者以全国30所高校5000多名大学生为被试,对影响大学生创业意向的诸多因素进行了分析。研究发现:当代大学生的创业意向在性别、奖学金获得次数、学生干部经历、出生地上均存在一定差异。大学生主客观条件中的性别、学校性质、创业兴趣、创意能力改善对创业意向有显著影响。创业教育和创业环境认知的引入对于预测大学生的创业意向均有增量效度,能够在个体的主客观条件以外解释个体创业意向的变异。在大学生认知中,影响创业成功的因素主要由客观背景资源、主观能力经验和外部宏观环境3个因子组成,其中主观能力经验的作用排在首位。 相似文献
152.
Stress can disrupt endocrine signalling in the male reproductive axis through high concentrations of glucocorticoids, the hallmark of stress. Our previous work revealed that a stress level of exogenous glucocorticoids could induce apoptosis of rat Leydig cells, which are the primary source of testosterone. The aim of this study was to investigate whether stress can induce apoptosis in rat Leydig cells in vivo and, if so, whether the process is the result of a direct effect of glucocorticoids. In a chronically stressed rat model, serum corticosterone concentration was increased significantly whereas serum testosterone was decreased. The frequency of apoptotic Leydig cells in stressed rats was also increased. Adrenalectomised rats subjected to chronic stress showed an elevated serum testosterone, while the apoptotic frequency of Leydig cells was not increased. It was established that glucocorticoid-induced Leydig cell apoptosis is mediated by glucocorticoid receptors (GRs), which translocate from cytoplasm to nucleus. Adenovirus microRNA-induced downregulation of GR expression in vitro alleviated the corticosterone-induced increase in apoptosis of Leydig cells. These results indicate that the stress-induced increase in corticosterone secretion resulted in apoptosis in rat Leydig cells in vivo, and thereby decreased testosterone synthesis. 相似文献
153.
Ono Y Lin HC Tzen KY Chen HH Yang PF Lai WS Chen JH Onozuka M Yen CT 《Stress (Amsterdam, Netherlands)》2012,15(2):207-217
We used 18F-fluorodeoxyglucose small-animal positron-emission tomography to determine whether different styles of coping with stress are associated with different patterns of neuronal activity in the hypothalamus. Adult rats were subjected to immobilization (IMO)-stress or to a non-immobilized condition for 30 min, in random order on separate days, each of which was followed by brain-scanning. Some rats in the immobilized condition were allowed to actively cope with the stress by chewing a wooden stick during IMO, while the other immobilized rats were given nothing to chew on. Voxel-based statistical analysis of the brain imaging data shows that chewing counteracted the stress-induced increased glucose uptake in the hypothalamus to the level of the non-immobilized condition. Region-of-interest analysis of the glucose uptake values further showed that chewing significantly suppressed stress-induced increased glucose uptake in the paraventricular hypothalamic nucleus and the anterior hypothalamic area but not in the lateral hypothalamus. Together with the finding that the mean plasma corticosterone concentration at the termination of the IMO was also significantly suppressed when rats had an opportunity to chew a wooden stick, our results showed that active coping by chewing inhibited the activation of the hypothalamic-pituitary-adrenal axis to reduce the endocrine stress response. 相似文献
154.
Yin-Hui Cheng Shih-Chieh Chuang Molly Chien-Jung Huang Wan-Chen Hsieh 《Current psychology (New Brunswick, N.J.)》2012,31(3):325-334
The framing effect demonstrates that two options with different risk levels affect people??s risk preferences, even if both options are logically equivalent. However, in reality we are almost always confronted with more than two choices, rather than a single manipulated message. In this paper, we simultaneously manipulate the framing effect and the context effect, including the attraction effect and the compromise effect, to examine the influence of context on framing. The results of two studies show that context influences the original choice preference arising from the framing effect. Moreover, the framing effect is reduced when context effects are introduced to the original choice set. 相似文献
155.
In 2 studies, we examined the use of validity screening items in adolescent survey data. In each study, adolescent respondents were asked whether they were telling the truth and paying attention in answering survey questions. In Study 1 (N = 7,801), the prevalence rates of student risk behaviors were significantly lower after inappropriate (invalid) responders were screened out of the sample. In addition, confirmatory and multigroup factor analyses demonstrated significant differences between the factor structures of school climate scales with valid versus invalid responders. In Study 2, student perceptions of school climate were correlated with teacher perceptions in 291 schools. A bootstrap resampling procedure compared the correlations obtained with valid versus invalid responding students in each school and found that valid responders had more positive views of school conditions and produced higher correlations with teacher perceptions. These findings support the value of validity screening items in improving the quality of adolescent survey data. 相似文献
156.
People can learn word–referent pairs over a short series of individually ambiguous situations containing multiple words and
referents (Yu & Smith, 2007, Cognition 106: 1558–1568). Cross-situational statistical learning relies on the repeated co-occurrence of words with their
intended referents, but simple co-occurrence counts cannot explain the findings. Mutual exclusivity (ME: an assumption of
one-to-one mappings) can reduce ambiguity by leveraging prior experience to restrict the number of word–referent pairings
considered but can also block learning of non-one-to-one mappings. The present study first trained learners on one-to-one
mappings with varying numbers of repetitions. In late training, a new set of word–referent pairs were introduced alongside
pretrained pairs; each pretrained pair consistently appeared with a new pair. Results indicate that (1) learners quickly infer
new pairs in late training on the basis of their knowledge of pretrained pairs, exhibiting ME; and (2) learners also adaptively
relax the ME bias and learn two-to-two mappings involving both pretrained and new words and objects. We present an associative
model that accounts for both results using competing familiarity and uncertainty biases. 相似文献
157.
Valente A Huang KH Portugues R Engert F 《Learning & memory (Cold Spring Harbor, N.Y.)》2012,19(4):170-177
The performance of developing zebrafish in both classical and operant conditioning assays was tested with a particular focus on the emergence of these learning behaviors during development. Strategically positioned visual cues paired with electroshocks were used in two fully automated assays to investigate both learning paradigms. These allow the evaluation of the behavioral performance of zebrafish continuously throughout development, from larva to adult. We found that learning improves throughout development, starts reliably around week 3, and reaches adult performance levels at week 6. Adult fish quickly learned to perform perfectly, and the expression of the learned behavior is manifestly controlled by vision. The memory is behaviorally expressed in adults for at least 6 h and retrievable for at least 12 h. 相似文献
158.
Wong YJ Nguyen CP Wang SY Chen W Steinfeldt JA Kim BS 《Cultural diversity & ethnic minority psychology》2012,18(3):258-267
The goal of this study was to identify diverse profiles of Asian American women's and men's adherence to values that are salient in Asian cultures (i.e., conformity to norms, family recognition through achievement, emotional self-control, collectivism, and humility). To this end, the authors conducted a latent profile analysis using the 5 subscales of the Asian American Values Scale-Multidimensional in a sample of 214 Asian Americans. The analysis uncovered a four-cluster solution. In general, Clusters 1 and 2 were characterized by relatively low and moderate levels of adherence to the 5 dimensions of cultural values, respectively. Cluster 3 was characterized by the highest level of adherence to the cultural value of family recognition through achievement, whereas Cluster 4 was typified by the highest levels of adherence to collectivism, emotional self-control, and humility. Clusters 3 and 4 were associated with higher levels of depressive symptoms than Cluster 1. Furthermore, Asian American women and Asian American men had lower odds of being in Cluster 4 and Cluster 3, respectively. These findings attest to the importance of identifying specific patterns of adherence to cultural values when examining the relationship between Asian Americans' cultural orientation and mental health status. 相似文献
159.
Shanshan Zhang Mingjie Zhou Jianxin Zhang Shuang Chen 《Asian Journal of Social Psychology》2012,15(4):231-237
The relationship between conscientiousness and job performance has been found to be nonlinear in the West, which challenges conceptually and empirically the traditional assumption of the single linear relationship. In this research, we examined the nonlinear effects of conscientiousness on both overall job performance and performance dimensions (i.e., task performance, adaptive performance and contextual performance) in the Chinese context. The results of our two studies supported some evidence for the nonlinear effect of conscientiousness on overall job performance. In addition, it was found that conscientiousness has different (linear or nonlinear) effects on performance dimensions. These findings suggest that the nonlinear effects of conscientiousness on job performance deserve further investigation, and a distinction should be made with regard to job performance in personnel evaluation. Results are discussed in terms of the significance of considering the nonlinear relationship between conscientiousness and performance criteria. 相似文献
160.
Using data from a national survey (N = 6,979) of young people in their last year in Norwegian secondary schools in 2007 (aged 18 and 19), this paper examines the effect of experience of violence including sexual abuse during childhood (before the age of 13) on the later academic achievement of young people. This investigation includes three types of violence: non-physical, physical and sexual, and two types of victimisation: being abused and witness to abuse. First we investigate the relationship between the experience of various violent acts before the age of 13 and young people??s later academic achievement. Second, applying the structural equation modelling technique, we take into account the effect of background factors such as parents?? educational attainment and gender, and the effect of mediating factors such as social capital and educational motivation on the academic achievement of the young victims. The results show that exposure to violence during childhood not only directly influences young people??s educational outcomes but also exerts indirect influences on their achievement through its impact on young victims?? social relations and psychological health. 相似文献