Prevalence of depressive symptoms and its correlates among medical students in China: a national survey in 33 universities

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.     

共享经济背景下顾客公民行为和不当行为：基于社会困境理论的视角

共享经济(个体供方对个体顾客的共享模式如小猪短租平台)中顾客公民行为的促进和不当行为的治理, 成为保证共享经济可持续发展的重要议题。然而, 现有顾客行为相关研究更多是在传统经济背景下进行的探讨, 而涉及到共享经济背景下的研究难以体现共享经济的特色, 导致其未能很好地解决实践困境。上述顾客行为是在个人和集体利益发生冲突时的抉择, 即社会困境。社会困境理论可以帮助企业全面认识顾客公民行为和不当行为并有效解决困境问题。本研究拟基于社会困境理论, 探讨以下三个方面的问题: (1) 深入剖析共享经济中顾客公民行为和不当行为的概念、维度及其测量; (2) 揭示平台、供方和政府通过规则制定或社会影响策略来有效优化顾客行为的路径; (3) 阐明顾客公民和不当行为的差异性影响机制, 以及顾客社会价值导向和供方监督对顾客行为的调节作用。本研究有助于拓展现有顾客公民和不当行为的研究, 为平台、供方和政府管理提供重要参考。     

快慢读者利用语境信息的差异：加工深度的作用

通过主题扫描和阅读理解两种加工深度不同的任务,考察快慢读者预测性效应差异的来源及加工深度在其中发挥的作用。被试在两种任务情境下阅读分别包含高低预测性目标词的96个句子框架,记录其眼动轨迹。结果显示：预测性效应仅在阅读理解任务中出现,快速读者在早期眼动指标上就表现出了预测性效应,慢速读者在晚期眼动指标上才表现出预测性效应。结果表明：加工深度调节快慢读者预测性效应的大小;在自然阅读情境下快慢读者的预测性效应表现符合预测编码框架假设。     

Pinning of grain boundary migration by a coherent particle

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.     

Microwave-dielectric and magnetic properties of Ta-doped BiFeO3 nanopowders

BiFe_{1? 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 BiFe_0.95Ta_0.05O₃ having the strongest ferromagnetism with a saturation magnetisation M _s of about 0.05 µ_B/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⁺.     

Psychological contracts and innovative behavior: a moderated path analysis of work engagement and job resources

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.     

工作场所排斥后的应对:期望和效价的作用*

基于期望-效价理论探讨了期望(关系修复可能性)和效价(关系重要性)对工作场所排斥后应对行为的影响。研究1采取回忆范式证实了遭遇工作场所排斥后个体将以积极、消极或不作为行为进行应对,而期望和效价对应对行为有显著预测作用;研究2在研究1基础上,通过情境问卷对期望和效价进行操纵,进一步验证了期望、效价与应对行为之间的因果关系,即关系修复可能性越大、关系越重要,个体越倾向以积极而非消极行为进行应对。     

句法加工中的预测现象及实验证据

句法加工是读者通过整合输入的言语信息来理解句子的过程。句法加工的存在,使得读者能够提前预测文本的信息,提高阅读效率。由于阅读离不开信息整合,研究者提出两类不同的句法理论:句法预测的模块局域性理论和句法预测的互动分析性观点。这两类理论的争论点在于句法加工是单独模块化的自上而下加工,还是自下而上-自上而下的互动分析加工过程。其区别表现为句法预测的作用——前者认为句法预测对句子加工有抑制作用,后者认为句法预测对句子加工起促进作用。来自眼动、ERP等研究的数据佐证了句法预测的存在。未来研究应围绕其差异进行深入探讨,以揭示句法加工的实质。     

Working memory in spatial knowledge acquisition: Differences in encoding processes and sense of direction

This study examined how different components of working memory are involved in spatial knowledge acquisition for good and poor sense‐of‐direction (SOD) people. We employed a dual‐task method, and asked participants to learn routes from videos with verbal, visual and spatial interference tasks and without any interference. Results showed that participants with a good SOD encoded landmarks and routes verbally and spatially, and integrated knowledge about them into survey knowledge with the support of all three components of working memory. In contrast, participants with a poor SOD encoded landmarks only verbally, and tended to rely on the visual component of working memory in the processing of route knowledge. Based on the results, a possible model for explaining the differences in spatial knowledge acquisition and SOD was proposed. Copyright © 2010 John Wiley & Sons, Ltd.