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141.
Xiong-Fei Pan Ying Wen Yun Zhao Jun-Mei Hu Si-Qi Li Shao-Kai Zhang 《Psychology, health & medicine》2016,21(7):882-889
We conducted a national survey among medical students in China to estimate the prevalence of depressive symptoms and explore associated risk factors based on an established questionnaire composed of demographic information, life events in the past four weeks before survey, and the validated Chinese version of the 21-item Beck’s Depression Inventory (BDI). The mean age of enrolled 9010 students was 20.7 (standard deviation: 1.6) years. BDI scores indicated that 19.9% had depressive symptoms based on the cut-off score of 14. Socioeconomic factors and student characteristics such as male sex, low monthly income per capita, father’s poor education background, and higher year of study were associated with higher prevalence of depressive symptoms among medical students. Students who studied in comprehensive universities were more likely to have depressive symptoms compared with those from medical universities. Habitual smoking and alcohol drinking, sleep deprivation, and hospitalization or medication for one week or more in the last four weeks also predisposed students to higher risk of depressive symptoms. Our results indicate that depressive symptoms are becoming a highly prevalent health problem among Chinese medical students. Primary and secondary prevention should be prioritized to tackle this issue based on potential risk factors. 相似文献
142.
随着互联网飞跃发展, 弹幕视频应运而生。这种新型的用户与视频交互方式具有新特性, 如用户情感表达实时动态性、情感分布多峰性。同时, 新特性也给实际研究工作带来挑战, 如用户画像刻画难度增大, 视频推荐和广告推送所需精度提高。现有研究尚未对弹幕视频的新特性进行深入分析, 也没有充分挖掘其本身所蕴含的学术研究价值。本文利用深度学习、自然语言处理技术、系统动力学方法, 结合心理学、市场营销学等多学科交叉前沿知识, 从数据驱动角度对弹幕视频数据进行分析和建模, 深度挖掘视频大数据潜在的商业价值。重点研究弹幕与视频双模态融合的情感识别方法; 构建带有用户情感特征的动态用户画像, 并建立基于用户画像的网络视频粘性营销机制; 分析用户情感与视频广告插播方式的相关性, 提出视频广告动态插播策略。丰富现有研究的同时, 为网络视频企业准确定位与分析用户需求, 创建高品质的智能营销平台供理论与决策支持。 相似文献
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We studied single-particle pinning of grain boundary (GB) migration during grain growth. A phase-field model was formulated to simulate the pinning by a coherent particle and validated quantitatively by comparison with analytical prediction. A study of GB migration velocity using this model revealed that second-phase coherent particles have a previously unknown restraining effect over the whole of the GB-particle interaction range, which is qualitatively different from the interaction between GB and incoherent particles. 相似文献
146.
BiFe1? x Ta x O3 (x = 0, 0.05, 0.1) nanopowders have been fabricated by a simple sol–gel method. Dielectric measurements at microwave frequencies (2–18 GHz) were made using a vector network analyser. Without tantalum, the BiFeO3 nanopowder presents a relaxation-like response with a characteristic frequency of 15 GHz, which can be associated with an overdamped process. The Ta-doped nanopowders, however, show resonant behaviour with resonant frequencies of 12.5 and 14.6 GHz. The intensity of the resonant peak near 14.6 GHz decreases with increasing Ta addition. This behaviour is associated with a damped resonance process. Room-temperature magnetic measurements indicate that the addition of Ta influences the magnetic properties of the BiFeO3 nanopowders, with BiFe0.95Ta0.05O3 having the strongest ferromagnetism with a saturation magnetisation M s of about 0.05 µB/Fe. The origin of the enhanced ferromagnetism is possibly associated with the distortion of the oxygen octahedral by the Ta substitution or/and the statistical distribution of Fe3+ and Fe2+. 相似文献
147.
Are risk-takers more likely to engage in unethical behaviors? We examined the relationship between risk-taking propensity and cheating in two experimental studies. In Study 1, we examined the relationship between subjects’ risk-taking propensity and their actual self-serving dishonesty using a gambling-like task. The results suggested that risk-taking propensity, measured using a behavioral approach, was positively correlated with actual self-serving dishonest behavior. In Study 2, we measured participants’ performances using a matrices test and found that the positive correlation still held. We found that participants with high risk-taking propensity reported a lower perceived probability of being detected, which might drive their dishonest behavior. 相似文献
148.
The present study assessed the impact on the work engagement of expatriates’ personal value orientation alignment with the host country’s national culture. Participants were 231 expatriates from seven countries who are working in Ethiopia (females = 17%; mean age = 36 years, SD = 2.72 years). The expatriates completed measures of personal value orientation, cross-culture adjustment, and work engagement levels. Structural equation modelling analysis indicated expatriates with personal value orientations that align with the host country’s national culture to have a higher work engagement level. Cross-cultural adjustment mediated the relationship between personal value orientation and work engagement. Expatriates’ personal value orientation fit with the host country’s national culture is a resource to accomplish their work successfully. 相似文献
149.
Huo‐Tsan Chang Hung‐Ming Hsu Jia‐Wen Liou Chi‐Tung Tsai 《Journal of applied social psychology》2013,43(10):2120-2135
This study explored the relationships between psychological contract types and innovative behavior. We focused on the mediating effect of work engagement and the moderating effect of job resources (organizational and social resources). Participants were 267 dyads of research and development engineers and their supervisors from 30 high‐tech companies. Moderated path analysis was used to test the hypotheses. Findings showed that: (a) work engagement fully mediated the negative relationship between transactional contracts and innovative behavior; in addition, it also fully mediated the positive relationship between relational contracts and innovative behavior; and (b) job resources attenuated the former and strengthened the latter mediating effects. These findings contribute to understanding how, why, and when psychological contract types lead to innovative behavior via work engagement. 相似文献
150.