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991.
Abstract

HIV can diminish quality of life profoundly, and it is important to understand and measure such effects of HIV and its treatments Although the term quality of life is commonly used, “health status” more accurately describes dimensions that are directly health related and that may be affected by traditional interventions. There is a substantial literature on general health status measurement, and several of the most established measures have been applied or adapted for use in HIV infected populations These measures include the Medical Outcomes Study health ratings, the Quality of Well-Being scale, and the Sickness Impact Profile. Cancer-specific measures such as the EORTC Quality of Life Core Questionnaire and the CARES have also been adapted. In the last three years, health status measures for HIV have been completed by several thousand patients, and have generally proved to be reliable and valid indicators of relevant clinical differences such as disease stage, numbers of symptoms, and other psychometic measures of disability and distress. Health status measures were included in a few completed clinical trials, and are being incorporated in a growing number of antiretroviral and antimicrobial studies. Health status measures provide the best way to evaluate psychosocial interventions directly aimed at improving patients' quality of life. Although challenges remain in further developing health status measures for HIV disease and in applying them, measurement of these concepts has proved to be both technically and operationally feasible. Measures of health status and quality of life can play an important role in the evaluation of clinical treatments in research studies, directing clinical treatment, assessing changes in health care delivery, and planning health care services.  相似文献   
992.
采用单探测变化检测范式,考察了单维度特征图形在视觉客体和视觉空间工作记忆中的存储机制,并对这两种视觉工作记忆的容量进行测定。结果显示,在客体工作记忆中,规则图形的记忆成绩显著高于不规则图形,但在空间工作记忆中,这两种图形的记忆成绩无显著差异;空间工作记忆的存储容量显著大于客体工作记忆容量,分别为4-5个位置和3-4个客体。这表明,图形规则性影响了客体工作记忆的存储但不影响空间工作记忆的存储,由单维度特征组成的图形在客体工作记忆中是以特征为单元储存,而在空间工作记忆中是以整合方式储存。  相似文献   
993.
计算机作为实验平台广泛应用于心理学实验中。本文指出计算机控制心理学实验的计时误差具有随机性、不可预知性,修正和优化难度大,并分析了原因。然后提出一种采用分布式任务处理和LED背光控制技术的新型心理实验系统,测试结果表明该系统在刺激呈现时间及反应时间精准度上优于计算机,为心理学实验平台的设计提供了新思路。  相似文献   
994.
采用Dehaene等人的研究范式,以计数单位中的“千”为基线,要求被试快速作大于“千”还是小于“千”的分类判断,考察计数单位在心理数字线上的空间表征方式.结果表明:(1)计数单位和数字有着相同的加工机制,小计数单位表征在心理数字线的左侧,大计数单位表征在心理数字线的右侧,存在显著的SNARC效应. (2) SNARC效应不仅仅出现在数量的空间表征上,同样能够出现在顺序信息的空间表征上.  相似文献   
995.
The negative impacts of excessive and problematic video game playing on both children and adults are attracting increasing concern. Based on self‐determination theory (SDT; Ryan & Deci, 2000), this study hypothesized that the three basic psychological needs of autonomy, competence, and relatedness are positively associated with purpose in life, which in turn acts as a protective factor against problem video game playing among Chinese young adult players. Through a questionnaire survey with a sample of 165 Chinese adults aged between 18 and 30 years (mean age = 22.7 years), we found that perceived autonomy, competence, relatedness, and purpose in life were all negatively correlated with problem game playing. The demographic and psychological factors explained 38% of the variances of problem game playing. Specifically, gender, perceived relatedness, and purpose in life emerged as the three most salient predictors of problem game playing among the Chinese young adults. The mediating role of purpose in life was evidenced and it was found that purpose in life mediated the influences of the psychological needs proposed by SDT on problem game playing. Moreover, young men were significantly more susceptible to problem game playing than their female counterparts. To conclude, psychological needs and purpose in life influenced Chinese young adults’ vulnerability to problem game playing directly or indirectly. Intervention programs that encourage social involvement and voluntary work, as well as counseling service that helps clients to search for life purpose, are suggested for intervening in problem game playing among Chinese young adults.  相似文献   
996.
Backward slope walking was considered as a practical rehabilitation and training skill. However, its gait stability has been hardly studied, resulting in its limited application as a rehabilitation tool. In this study, the effect of walking direction and slope grade were investigated on the local dynamic stability of the motion of lower extremity joints and trunk segment during backward and forward upslope walking (BUW/FUW). The local divergence exponents (λS) of 16 adults were calculated during their BUW and FUW at grades of 0%, 5%, 10%, and 15%. Mean standard deviation over strides (MeanSD) was analyzed as their gait variability. Backward walking showed larger λS for the abduction-adduction and rotational angles of knee and ankle on inclined surface than forward walking, while λS for hip flexion-extension angle at steeper grades was opposite. No grade effect for any joint existed during BUW, while λS increased with the increasing grade during FUW. As to the trunk, walking direction did little impact on λS. Still, significant larger λS for its medial-lateral and vertical motion were found at the steeper grades during both FUW and BUW. Results indicate that during BUW, the backward direction may influence the stability of joint motions, while the trunk stability was challenged by the increasing grades. Therefore, BUW may be a training tool for the stability of both upper and lower body motion during gait.  相似文献   
997.
Growing international research interest in negative-leadership behaviors prompts the need to examine whether measures of ineffective leadership developed in the United States are equivalent across countries outside the United States. B. J. Tepper's (2000) abusive supervision measure has been used widely inside and outside the United States and merits research attention on its construct equivalence across different cultural settings. The authors conducted a series of multigroup confirmatory factor analyses to investigate the measurement equivalence of this measure across Taiwan (N = 256) and the United States (N = 389). Configural invariance was established, suggesting that both U.S. and Taiwanese samples perceive abusive supervision as a single-factor concept. Furthermore, the establishment of partial metric invariance and partial scalar invariance suggests that the abusive supervision measure is applicable to crosscultural comparisons in latent means, construct variance, construct covariances, and unstandardized path coefficients with the caution that workers from different cultures calibrate their responses differently when answering some items.  相似文献   
998.
This study investigated gender differences in anxiety and coping styles under the stress of intense military training. We surveyed Chinese female (n = 470) and male (n = 379) military officers who were surveyed during the third month of a 10-month intensive training program. Results indicated that state and trait anxiety were highly correlated in both women and men. In general, female officers had higher levels of anxiety, greater negative coping tendencies, and less perceived self-efficacy than their male counterparts. When compared with the norm, both women and men had significantly more positive coping strategies. A hierarchical multiple regression analysis showed factors that influenced male and female state anxiety. Avoidance, which was chosen by women more often than men, in general was less useful for female officers. The most common positive coping style for female officers was problem solving, whereas for men it was help seeking. We suggested that even female officers with lower mental health levels than their male counterparts made active cognitive changes to their coping styles when undergoing intense military training.  相似文献   
999.
A series of large-scale molecular dynamics simulations have been performed to investigate the tensile properties and atomistic deformation mechanisms for the nanostructured Cu with three typical microstructures: the hierarchical structure consisting of both twin-free grains (d?=?70?nm) and grains with bundles of smaller nanotwins (d?=?70?nm, λ?=?10?nm), the fully nanograined structure and the fully nanotwinned structure. The average flow stress of the hierarchically structure is found to be higher than that calculated by rule of mixture. As compared with that of fully nanograined structure, the strength for the twin-free grains in the hierarchical structure is promoted and gives extra hardening due to the increased dislocation density and dislocation behaviours. It is also found that the nanotwin bundles are more deformable than the twin-free grains in the hierarchical structure according to the deviatoric strain invariant contour. This indicates that the fully nanograined structure cannot only be strengthened to a higher level, but also obtain better ductility by embedded with stronger bundles of smaller nanotwins. Thus, a superior strength–ductility synergy could be obtained in this kind of hierarchical structures, and this novel strategy has also been implemented in bulk austenitic steels or copper by recent experiments.  相似文献   
1000.
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