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101.
Research findings show that there is marked variability in children's response to parental separation, but few studies identify the sources of this variation. This prospective longitudinal study examines the factors modifying children's adjustment to parental separation in a community sample of 5,635 families in England. Children's behavioral/emotional problems were assessed when children were aged 47 and 81 months; marital quality, maternal depression, socioeconomic circumstances, and demographic variables were assessed prior to the separation from maternal report. Results indicated that 346 mothers separated from their partners in the 3-year period. Preseparation differences were found for measures of family process and parent risk factors, with effect sizes ranging from small to trivial. Parental separation was associated with a significant but modest increase in behavioral/emotional problems, independent of marital quality, maternal depression, socioeconomic circumstances, and demographic variables. Moderation analyses showed that children of cohabiting parents had a greater increase in adjustment problems following parental separation than children of married parents. Further research elucidating the factors that moderate children's adjustment to parental separation is needed to improve our understanding of who may most likely benefit from preventive interventions.  相似文献   
102.
华西圣教书会于1899年初成立于重庆,存续40余年,于1941年关闭,是基督教在华西地区最重要的文字机构之一①.本文以清末民初为时限,考察华西圣教书会成立过程及其出版、发行状况,并分析基督教文字事业对华西社会变迁所起到的重大作用.  相似文献   
103.
Human visual attention operates in a context that is complex, social and dynamic. To explore this, we recorded people taking part in a group decision-making task and then showed video clips of these situations to new participants while tracking their eye movements. Observers spent the majority of time looking at the people in the videos, and in particular at their eyes and faces. The social status of the people in the clips had been rated by their peers in the group task, and this status hierarchy strongly predicted where eye-tracker participants looked: high-status individuals were gazed at much more often, and for longer, than low-status individuals, even over short, 20-s videos. Fixation was temporally coupled to the person who was talking at any one time, but this did not account for the effect of social status on attention. These results are consistent with a gaze system that is attuned to the presence of other individuals, to their social status within a group, and to the information most useful for social interaction.  相似文献   
104.
Four studies were conducted to develop and validate the Coping With Discrimination Scale (CDS). In Study 1, an exploratory factor analysis (N = 328) identified 5 factors: Education/Advocacy, Internalization, Drug and Alcohol Use, Resistance, and Detachment, with internal consistency reliability estimates ranging from .72 to .90. In Study 2, a confirmatory factor analysis (N = 328) provided cross-validation of the 5-factor model as well as evidence for validity of the scale. The validity evidence was similar across racial groups and for males and females. In Study 3, the estimated 2-week test-retest reliabilities (N = 53) were between .48 and .85 for the 5 factors. Education/Advocacy, Internalization, Drug and Alcohol Use, and Detachment were positively associated with active coping, self-blame, substance use, and behavioral disengagement, respectively, providing further support for validity of the CDS. Finally, incremental validity evidence was obtained in Study 4 (N = 220), where it was shown that the CDS explained variance in outcome variables (i.e., depression, life satisfaction, self-esteem, and ethnic identity) that could not be explained by general coping strategies.  相似文献   
105.
Archival data (N = 1,048 women, 1,136 men) from a mental health survey of college students were used to investigate incidence of nonsuicidal self-injury (NSSI), including cutting. Significant levels (defined as 4-5 lifetime incidents) were found in 9.3% of women and 5.3% of men. The Counseling Center Assessment for Psychological Symptoms (a global symptom inventory) and an assessment of trauma had been field tested with this sample. We randomly partitioned half of these data into a holdout sample and used the remainder to develop an NSSI screening inventory that included (a) 5 women's screening items, including 1 item to assess trauma experienced; (b) 11 men's screening items; and (c) 12 items common to men and women, including depression, dissociation, anger, unwanted thoughts, nightmares or flashbacks, and having witnessed trauma. Logistic regression and receiver-operating characteristic curve analysis suggested the inventory significantly discriminated NSSI men and women in the holdout sample, p < .001. Cutoff scores were identified to correctly classify about 48% of the true positive male and female NSSI cases, with false positive rates of 13.2% and 8.4% for women and men, respectively.  相似文献   
106.
This paper studies changes of standard errors (SE) of the normal-distribution-based maximum likelihood estimates (MLE) for confirmatory factor models as model parameters vary. Using logical analysis, simplified formulas and numerical verification, monotonic relationships between SEs and factor loadings as well as unique variances are found. Conditions under which monotonic relationships do not exist are also identified. Such functional relationships allow researchers to better understand the problem when significant factor loading estimates are expected but not obtained, and vice versa. What will affect the likelihood for Heywood cases (negative unique variance estimates) is also explicit through these relationships. Empirical findings in the literature are discussed using the obtained results.  相似文献   
107.
多体素模式分析(multi-voxel pattern analysis,MVPA)是一种基于机器学习理论发展出来的新的功能磁共振数据分析技术。MVPA技术通过训练分类器,对由不同认知状态引起的多体素信号模式进行分类。与传统的基于单个体素的分析方法相比,该技术可更敏感地检测脑对认知状态的表征,并使得从神经信号解码认知状态成为可能。文章介绍MVPA技术的基本原理、分析步骤以及可以用MVPA来解决的科学问题,并对应用中可能面临的问题提供了参考建议。  相似文献   
108.
Abstract

A quasicrystalline Al-Fe phase has been formed by room-temperature ion mixing of AI-Fe multiple layers with no additional postannealing. The quasicrystalline phase was dispersed as grain in an amorphous matrix. The size of the grains was about 10-30nm, and the composition was determined to be Al80Fe20. The structure of the quasicrystalline phase was identified by calculating some 20 sharp diffraction rings in the selected-area diffraction pattern and found to be similar to that of the rapidly quenched AI-Mn quasicrystalline phase.  相似文献   
109.
The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning.  相似文献   
110.
Cellular precipitation (also known as discontinuous precipitation) has been observed at the grain boundaries of a newly developed nickel-based Inconel740H alloy designed for use at 700?°C in advanced ultrasupercritical coal-fired power plants. By means of element mapping and selected area diffraction, the cellular precipitates were identified as Cr-rich M23C6 carbides. The onset of cellular precipitation was found to follow a pucker mechanism in Inconel740H. The cellular precipitates at the grain boundaries, even at low volume fractions, were severely detrimental to the creep strength at 750?°C. The creep rupture life of Inconel740H containing cellular precipitates at grain boundaries was only one-tenth of that for the alloy without cellular precipitates. The reason for the drastically decreased creep rupture life is attributed to the poor resistance of cellular precipitates to crack propagation during creep.  相似文献   
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