MEMS薄膜平均应力梯度在线测量方法

结构层淀积是MEMS加工过程中的重要工艺步骤,淀积薄膜的应力梯度是影响MEMS器件性能的一个重要的力学参数．文中介绍了几种常见的平均应力梯度在线测量方法,阐明了其测试结构及测量原理,并对这些测量方法进行了比较．     

Childhood trauma and neighborhood-level crime interact in predicting adult posttraumatic stress and major depression symptoms

Previous research has identified several individual-level factors that modify the risk of childhood trauma on adult psychiatric symptoms, including symptoms of major depression (MD) and posttraumatic stress (PTS). Neighborhood-level factors also influence the impact of individual-level exposures on adult psychopathology. However, no prior studies to our knowledge have explored cross-level interactions between childhood trauma and neighborhood-level factors on MD and PTS symptoms. The purpose of this study was therefore to explore cross-level interactions between a neighborhood-level factor – neighborhood-level crime – and childhood trauma on MD and PTS symptoms. Participants in this study (N = 3192) were recruited from a large public hospital, and completed self-report inventories of childhood trauma and MD and PTS symptoms. Participant addresses were mapped onto 2010 census tracts, and data on crime within each tract were collected. Multilevel models found a significant cross-level interaction between childhood trauma and neighborhood crime on MD symptoms, such that the influence of high levels of childhood trauma on MD symptoms was enhanced for participants living in high-crime neighborhoods. Supplementary analyses found variation in the strength of cross-level interaction terms by types of childhood trauma and crime, with the strongest associations including emotional neglect paired with personal and property crime. The results provide preliminary support for interventions that help childhood trauma survivors find housing in less vulnerable neighborhoods and build skills to cope with neighborhood crime.     

局部硬化区对焊接热影响区断裂萌生的影响

采用二维有限元数值方法分析了焊接热影响区粗晶区（ＣＧＨＡＺ）中局部硬化区（ＬＨＺ）的作用。当含有ＬＨＺ时，大大提高了ＬＨＺ内的应力并引起应变在ＬＨＺ和基体界面处产生不连续分布。ＬＨＺ的形状强烈影响ＬＨＺ内部的应力，在细长ＬＨＺ内几乎整体均呈现高应力分布，而块状ＬＨＺ仅在边缘区域出现应力集中。即使ＬＨＺ含量相同，随ＬＨＺ细长比的增大，ＬＨＺ内峰值应力及高应力区面积增加，说明细长ＬＨＺ容易在低应力水平下诱发断裂。这一结果在高强钢焊接热影响区ＣＴＯＤ试验中得到证实。含细长ＭＡ组元的ＣＧＨＡＺ在低得多的ＣＴＯＤ水平下发生断裂，因此控制ＭＡ组元的形状能够大大改善ＣＧＨＡＺ的韧性。     

Teacher self-efficacy moderates the relations between imposed pressure from imposed curriculum changes and teacher stress

Based on the Job Demands-resources (RD-R) model, the aim of the current study was to examine how pressure arising from imposed curriculum changes and teacher self-efficacy relate to perceived stress in teachers. Participants (839 teachers working in English schools) completed an online survey that contained questions about demographics, self-reported pressure from imposed curriculum changes, teacher self-efficacy, and perceived stress. Pressure from imposed curriculum changes was positively, and teacher self-efficacy negatively, related to perceived stress. Teacher-self efficacy moderated relations between pressure from imposed curriculum changes and perceived stress. High teacher self-efficacy was associated with lower perceived stress, relative to low teacher self-efficacy, when pressure from imposed curriculum changes was low. The differential advantage offered by high self-efficacy declined as pressure from imposed curriculum changes increased.     

Effects of a Brief Mindfulness Based Group Intervention On College Students

Increases in the number of college students seeking mental health services require counseling centers to explore innovative strategies to provide effective and efficient treatments. Group interventions offer an alternative to traditional individual counseling, allowing centers to serve more students with fewer clinical staff (Burlingame et al., 2016). Of current group modalities, mindfulness-based interventions (MBIs) have been growing in popularity as an effective approach for addressing college students’ increasingly complex needs. This study describes the evaluation of a three-session mindfulness-based intervention on students’ mindfulness, symptoms, and stress. Compared to a comparison group of 109 students not seeking counseling center services, 78 students who received the intervention reported increased mindfulness, and decreased symptoms of depression, anxiety, and stress at the end of the group. Furthermore, improvements in mindfulness mediated intervention effects on symptoms of depression and anxiety. These gains were generally maintained 3 weeks later. These findings support the benefits of brief group interventions for college students. Suggestions for modifications to the intervention and for future research are discussed.     

The relationship between exposure to family violence in childhood and post-traumatic stress symptoms in young adulthood: The mediating role of social support

BackgroundExtensive research has examined the relationship between exposure to family violence and its long-term mental health effects. Social support has been found to moderate this relationship, but there is a dearth of research on its mediating role.ObjectivesThe article presents the results of a study on the relationship between witnessing interparental violence and experiencing parental violence during childhood and adolescence on the one hand, and post-traumatic stress symptoms (PTSS) during young adulthood on the other. In addition, the article presents results on the role of social support as a mediator in this relationship.Method, participants, and settingA cross-sectional survey was conducted among 516 Israeli university and college students (90.7% female, and 9.3% male; M age = 24.9, SD = 2.7) using a retrospective, self-administered questionnaire.ResultsThe results revealed that exposure to each pattern of family violence (i.e., witnessing interparental violence and experiencing parental violence) predicted higher levels of PTSS. Furthermore, social support was found to partially mediate the relationship between exposure to family violence during childhood and adolescence and current PTSS as well as its four symptoms, i.e., depression, sleep disturbance, dissociation, and anxiety.ConclusionsThe results of the current study highlight the important role of social support in the association between adversities experienced early in life and young adulthood outcomes. The findings are interpreted on the basis of Conservation of Resources Theory (Hobfoll et al., 1990), which served as the conceptual framework for the study. The limitations of the study and implications for future research are discussed.     

Becoming Fathers: Initial Exploration of a Support Program for New Fathers

Emerging fathers experience a variety of stressors, including identity and role transitions, changes in their relationships, and challenges in developing caregiving skills. Increasing expectations for father involvement in childcare are emphasizing the importance of the father role, but social supports for new fathers remain scarce. Nineteen expectant and new fathers participated in a pilot 5-week group intervention aimed at improving stress coping and involvement attitudes using a combination of mindfulness practices and skill-building for parenting and partner communication. We administered surveys pre- and postintervention to assess efficacy in the areas of stress, depressive symptoms, father involvement attitudes, and mindfulness. Within-participant differences were compared across participants as well as examining individual reliable change. Results indicated initial reductions in stress and depressive symptoms and increases in the mindfulness constructs of nonjudgment and nonreactivity. No significant changes were found in father involvement attitudes. Perinatal intervention specific to fathers holds promise as an underexplored avenue for supporting families across the transition to parenthood.     

中美大学生英语重音节奏模式的对比研究

英语是典型的重音节拍语,重音是它区别意义的主要语音手段。汉语是典型的音节节拍语,每个音节都有明确的四声调值,声调是汉语区别语义的主要语音特征。汉英语言节奏模式的巨大差异是中国英语学习者习得地道英语口语的最大障碍。本文通过对比中关大学生对同一英语文本的朗读语音数据,旨在找出学习者的重音误用规律。研究发现,在无标记调核调群中,本族语者的重音模式完全一致,而学习者出现多重音现象;在有标记调核调群中,本族语者除极少部分调核重音出现误置外,其它重音模式仍然高度一致,而学习者的重音模式非常混乱,存在调核误置、多重音及重音缺失等现象。本文的研究对习得正确的英语节奏模式有一定的指导意义。     

Effect on growth and productivity of lutein from the chlorophyta microalga,strain MCH of Muriellopsis sp., when grown in sea water and outdoor conditions at the Atacama Desert

BackgroundMicroalgae are microorganisms that produce various products, for example, pigments, mainly carotenoids. This study aimed to used the strain of Muriellopsis sp. and to evaluate their behavior when grown in freshwater and seawater, along with indoor and outdoor conditions for both cultures. Growth of the strain was evaluated by determining its biomass, lutein productivity with high-performance liquid chromatography (HPLC), and antioxidant activity by using the 2,2-diphenyl-1-picrilhydrazil (DPPH method).ResultsMuriellopsis sp. strain in indoor cultures showed an increased antioxidant activity. In outdoor conditions, both cultures showed increased cells number, concentration of biomass, and lutein productivity. The percentage of lutein obtained from the strain MCH in indoor conditions was 25 times higher than that reported for calendula, reaching 0.75% of lutein in Muriellopsis sp. cultured in seawater, followed by 0.6% in Muriellopsis sp., cultures in freshwater at day 12 of both cultures. These values exceed that of microalgae Scenedesmus almeriensis, which reaches 0.53% lutein.ConclusionsThe results show that the native strain of the Atacama Desert is one of the largest producers of lutein as compared to those reported to date. The study demonstrated the feasibility of producing this carotenoid with well-known properties to prevent some diseases due to its high nutritional value. Muriellopsis sp. cultivation in open-air seawater is a good precedent for developing mass production of this species in an area where freshwater is scarce and costly.How to cite: Cruz-Balladares V, Marticorena P, Riquelme C. Effect on growth and productivity of lutein from the chlorophyta microalga, strain MCH of Muriellopsis sp., when grown in sea water and outdoor conditions at the Atacama Desert. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.09.001     

Longitudinal analysis of Chinese high school student’s stress in school and academic achievement

In previous research, few studies have examined the effects of adolescents’ stress in school on the change rates of their academic achievement. In the present study, we seek to examine the longitudinal relationships between adolescents’ stress in school and the change rates of their academic achievement. The results indicated that for those whose academic achievement significantly declined over time, the students’ stress from teacher–student interaction significantly predicted the change rates of their academic achievement. The findings provided support to the notion that stress was a risk factor in students’ academic development.