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71.
High impact strength poly(phenylene oxide)-polyamide blends can be prepared by chemically coupling the two components and incorporating a rubbery impact modifier in the resin. The resulting materials exhibit a distinctive morphology in which the rubber is selectively incorporated in the dispersed poly(phenylene oxide) phase. In this paper both the structure and toughening mechanisms in these blends are examined. An analysis of their deformation behaviour is presented in a companion paper.  相似文献   
72.
Organizations today face shortages of IT personnel. We investigated workplace factors in one state government in hope of identifying factors that influence perceived organizational support (POS) within an IT work environment. A combination of job characteristics (challenging job and perceived workload), job stressors (work exhaustion, role conflict, and role ambiguity), and the organization’s discretionary actions (pay-for-performance and mentoring opportunities) were measured and hierarchical regression was used to determine the relationships. Four control variables were also included (age, gender, organizational tenure, and professional versus administrator status). Role ambiguity, role conflict, work exhaustion, career mentoring, and pay-for-performance together explained 62% of the variance in the IT employees’ POS. Career mentoring and role ambiguity explained most of the variance.  相似文献   
73.
There is a long and varied usage of self-help housing policy in South Africa, dating from colonial times when Africans were dumped in locations and left to build their own housing, to the present post apartheid reconstruction. The paper documents and periodises the adoption of self-help strategies for housing the African population of South African cities throughout the 20th century. Exploration of the practice of self-help housing practices in Johannesburg suggests that owner construction is a prevailing method of social engineering, whose acceptance or rejection reflects perceived political and economic advantages for the state and the private sector, and is not a simple response to a shortage of affordable shelter among the poor.  相似文献   
74.
Fragile X-associated tremor/ataxia syndrome (FXTAS) develops in a subset of fragile X premutation carriers and involves gait ataxia, action tremor, Parkinsonism, peripheral neuropathy, autonomic disorders, and cognitive impairment. The study was designed to define the nature of cognitive deficits affecting male premutation carriers with and without FXTAS. A sample of 109 men underwent motor, cognitive, genetic, and neurologic testing, as well as brain magnetic resonance imaging. Subjects were classified into 3 groups: (a) asymptomatic premutation carriers, (b) premutation carriers with FXTAS, and (c) normal controls. Men with FXTAS performed worse than controls on mental status, intelligence, executive cognitive functioning (ECF), working memory, remote recall of information, declarative learning and memory, information processing speed, and temporal sequencing, as well as 1 measure of visuospatial functioning. Language and verbal comprehension were spared. Asymptomatic carriers performed worse than controls on ECF and declarative learning and memory. This comprehensive examination of cognitive impairment in male premutation carriers suggests that FXTAS involves substantial executive impairment and diffuse deficits in other cognitive functions. Longitudinal research currently underway will provide insight into the progression of the disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
Socioemotional selectivity theory postulates that with age, people are motivated to derive emotional meaning from life, leading them to pay more attention to positive relative to negative/neutral stimuli. The authors argue that cultures that differ in what they consider to be emotionally meaningful may show this preference to different extents. Using eye-tracking techniques, the authors compared visual attention toward emotional (happy, fearful, sad, and angry) and neutral facial expressions among 46 younger and 57 older Hong Kong Chinese. In contrast to prior Western findings, older but not younger Chinese looked away from happy facial expressions, suggesting that they do not show attentional preferences toward positive stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
Parkinson's disease (PD) is a neurodegenerative disorder in which loss of dopaminergic (DA) neurons (>50%) in the substantia nigra (SN) precedes most of the overt motor symptoms, making early diagnosis and treatment interventions difficult. Because PD has been associated with free radicals generated by nitric oxide, this study tested whether treatments of 7-nitroindazole (7NI), a nitric-oxide-synthase inhibitor, could reduce cognitive deficits that often emerge before overt motor symptoms in a presymptomatic rat model of PD. Rats were given intraperitoneal injections of 50 mg/kg 7NI (or vehicle) just before receiving bilateral, intrastriatal injections of the DA-toxin, 6-hydroxydopamine (6-OHDA). The rats were then given a battery of motor tasks, and their learning ability was assessed using a spatial reversal task in a water-T maze. Results indicate that 7NI treatments attenuate 6-OHDA-induced spatial learning deficits and protect against DA cell loss in the SN, suggesting that 7NI may have potential as an early, presymptomatic pharmacotherapy for PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
Intimate partner violence is a serious and pervasive social problem with deleterious consequences for survivors’ well-being. The current study involved interviewing 160 survivors 6 times over 2 years to examine the role of social support in explaining or buffering these negative psychological consequences. The authors examined both between- and within-persons variability to explore women’s trajectories regarding their experiences of abuse, social support, depression, and quality of life (QOL). Findings revealed the complex role of social support on women’s well-being. Evidence was found for main, mediating, and moderating effects of social support on women’s well-being. First, social support was positively related to QOL and negatively related to depression. Social support also partially explained the effect of baseline level and subsequent change in physical abuse on QOL and depression over time, partially mediated the effects of change in psychological abuse, and moderated the impact of abuse on QOL. The buffering effects of social support were strongest at lower levels of abuse. Implications for future research and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Previous research has suggested that like animal and social fear-relevant stimuli, other-race faces (African American) are detected preferentially in visual search. Three experiments using Chinese or Indonesian faces as other-race faces yielded the opposite pattern of results: faster detection of same-race faces among other-race faces. This apparently inconsistent pattern of results was resolved by showing that Asian and African American faces are detected preferentially in tasks that have small stimulus sets and employ fixed target searches. Asian and African American other-race faces are found slower among Caucasian face backgrounds if larger stimulus sets are used in tasks with a variable mapping of stimulus to background or target. Thus, preferential detection of other-race faces was not found under task conditions in which preferential detection of animal and social fear-relevant stimuli is evident. Although consistent with the view that same-race faces are processed in more detail than other-race faces, the current findings suggest that other-race faces do not draw attention preferentially. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
The authors examined secure base functioning in couples by studying the association between daily social support experiences and attachment security in a 14-day daily experiences study of 114 heterosexual dating couples. Both members of each couple reported on daily relationship-specific attachment security and support sought, provided, and received, as well as felt support. Within- and cross-partner associations were examined, as were reciprocal associations between support and security. Results of over-time Actor-Partner Interdependence Model analyses indicated that security (in the form of high comfort with intimacy and low anxiety about abandonment) was associated with the most adaptive support experiences, whereas high anxiety about abandonment was associated with the least, and particularly with a lack of sensitive caregiving. Implications for understanding secure base dynamics in couples are discussed and guidelines for where to intervene as well as what to target in relationship distress prevention programs are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
The role of emotion dysregulation in the intergenerational transmission of romantic relationship conflict was examined using multimethod and multiagent prospective longitudinal data across 21 years for 190 men and their mothers and fathers. As predicted, an individual’s emotion dysregulation was a key mediator in the transmission of relationship conflict, along with poor parenting skills. Parents’ emotion dysregulation was directly related to their son’s emotion dysregulation, which was in turn associated with the son’s later relationship conflict. Additionally, parents’ emotion dysregulation was significantly related to their poor discipline skills, which were linked to the son’s emotion dysregulation and eventual relationship conflict. Findings highlight emotion dysregulation as a significant mechanism explaining the continuity of romantic relationship conflict across generations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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