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961.
Previous studies have shown that negative emotional distracters impair conscious inhibitory control. Recent research has shown that inhibitory control can be triggered unconsciously; therefore, in Experiment 1, we aimed to investigate whether negative emotional distracters affect unconscious inhibitory control. Furthermore, in Experiment 2, we examined whether fearful and disgusting distracters have differential effects on unconscious inhibitory control. Participants were instructed to perform a masked Go/No-Go task superimposed on a negative or neutral image cue (Experiment 1) or on a fearful, disgusting or neutral image cue (Experiment 2). Results showed that negative emotional distracters impaired unconscious inhibitory control; furthermore, disgusting distracters impeded unconscious inhibitory control when compared to fearful ones. This study is the first to provide evidence that fear and disgust may affect unconscious inhibitory control differently. These results expand the understanding of the relationship between emotions and inhibitory control.  相似文献   
962.
Tungsten (W) is cited as a candidate first-wall material in fusion reactors owing to its outstanding thermal properties and erosion resistance. An important issue is that the energetic isotopes of hydrogen, tritium (T) and deuterium (D) and helium (He) particles damage the surface of W in fusion reactors. He particles cause more notable damage than D or T because the binding energy of defects and He is larger than that of defects and D or T. In this study, well-annealed W specimens were implanted with 5 keV He ions at room temperature and irradiation dosages of 1.0 × 1020 and 2.5 × 1021 ions/m2. Then, thermal desorption spectroscopy analysis was performed by heating the samples to 1973 K at a ramping rate of 0.5 K/s. Thermal desorption of He in the sample irradiated with a low dosage occurred at 1400 and 1960 K, whereas that in the sample irradiated with a high dosage occurred at 740, 1050 and 1500 K. According to the microstructures observed using transmission electron microscopy, both peaks in the former case were attributed to He de-trapping from irradiation to nduced helium-vacancy clusters of different sizes, whereas the peaks in the latter case were attributed to He de-trapping from surface defects, irradiation-induced dislocation loops and tiny helium-vacancy clusters, respectively.  相似文献   
963.
The addition of Ag to the age hardenable Mg–Gd–Zr alloy system dramatically enhances early stage age hardening kinetics. Using atom probe tomography (APT), Ag-rich clusters were detected in a Ag-containing Mg–Gd–Zr alloy immediately after solution treatment and water quenching. During subsequent isothermal ageing at 200 °C, a high density of basal precipitates was observed during the early stages of ageing. These basal precipitates were enriched with Ag and Gd, as confirmed by APT. It is posited that Ag-rich clusters in the context of quenched-in vacancies can attract Gd atoms, increasing diffusion kinetics to facilitate the formation of the Ag + Gd-rich basal precipitates. The rapid formation of Ag + Gd-rich precipitates was responsible for accelerated ageing.  相似文献   
964.
We report that <c+a> pyramidal slipping could be more easily activated in textured Mg–Ca alloys with increasing Ca contents dissolved in α-Mg matrix under tensile deformation, and it is proposed that the decreased stacking fault energy plays the critical rule. In contrast, only twins and <a> basal dislocations are observed in the compressed samples. The results would provide insight into understanding of the deformation mechanism and designing more ductile Mg alloys.  相似文献   
965.
张一兵 《哲学研究》2016,(4):68-77,129
索恩-雷特尔第一次明确提出用历史唯物主义的方式重新解读康德的"认识论革命",在他这里,康德的认识论构架本身是商品生产中发生的特定历史结果,知识的形式能够先验于感性世界,恰恰因之于脑力劳动从体力劳动中的历史性挣脱和分离。这种分离遮蔽了劳动创造性关系在商品交换活动的现实抽象所生成的一种构序社会存在的客观的社会先验性,而这种社会先验才是康德-黑格尔先验观念的真正根据。索恩-雷特尔第一次指认了商品交换中发生的现实抽象并不仅仅是主观思维的活动机制,作为概念生成的真正劳作工地是发生于社会存在中的一种客观抽象,恰恰是这种现实抽象建构了先验的社会生活形式,并由此规制了思维形式的主观抽象活动以生成思维形式。  相似文献   
966.
967.
According to family investment theory, a family’s socio-economic status can have a noteworthy impact on the academic performance and future lives of adolescents. However, the mechanism for this remains poorly understood. We examined the mediating and moderating effects of family emotional and cultural environment on the relations between family socio-economic status and learning burnout. Specifically, we investigated whether different family emotional environments have a moderating effect on the relationship between family socio-economic status and learning burnout and on the mediating effect of family cultural environment. A sample of 1181 junior and senior high school students completed multidimensional measures of family socioeconomic status, family emotional and cultural environment, and learning burnout. A regression analysis showed that socio-economic status significantly predicted learning burnout. The achievement, cultural, and recreational dimensions of family cultural environment were all mediators of this relationship. Moreover, cultural dimension was moderated by the family conflicts factor of family emotional environment.  相似文献   
968.
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   
969.
In China, the gender ratio of suicide rates did not match the Western patterns, which was higher for females than males. However, the rural men were at relatively high risk of suicide in Liaoning province. Impulsivity was an important factor of suicide behaviors, but there was a lack of studies in China. This research aimed to study the relationship between impulsive personality traits and suicidal behavior among Chinese rural youths. Suicides were consecutively sampled from six randomly selected counties in Liaoning Province in China. Between 2005 and 2007, a total of 162 suicide victims were enrolled in the study along with 162 community controls matched for age, gender, and location. The psychological autopsy method was used to collect data from informants knowledgeable about the selected suicide victims and controls. The results showed the suicide victims in the study were more likely to demonstrate dysfunctional impulsivity and less likely to demonstrate functional impulsivity compared with the controls. Mental disorders, acute negative life events, and dysfunctional impulsivity contributed to the risk of suicide; educational and functional impulsivity were protective factors. Suicide prevention efforts in rural China may address impulsivity.  相似文献   
970.
Recent studies have provided evidence that there are two possible systems for empathy: affective empathy (AE) and cognitive empathy (CE). Neuroimaging paradigms have proven that the insular cortex is involved in empathy processing, particularly in AE. However, these observations do not provide causal evidence for the role of the insula in empathy. Although impairments in empathy have been described following insular damage in a few case studies, it is not clear whether insular cortex is involved in CE and whether these two systems are impaired independently or laterally in patients with insular gliomas. In this study, we assessed 17 patients with an insular glioma, 17 patients with a noninsular glioma, and 30 healthy controls using a method that combined a self-report empathy questionnaire with the emotion recognition task, assessment of empathy for others’ pain, and the emotional perspective-taking paradigm. We found that patients with an insular glioma had lower scores for empathic concern and perspective taking than did either healthy controls or lesion controls. The patients’ abilities to recognize facial emotions, perceive others’ pain, and understand the emotional perspectives of others were also significantly impaired. Furthermore, we did not observe a laterality effect on either AE or CE among those with insular lesions. These findings revealed that both AE and CE are impaired in patients with an insular glioma and that the insular cortex may be a central neuroanatomical structure in both the AE and CE systems.  相似文献   
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