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131.
In a longitudinal prospective study, mood fluctuations were assessed for evidence of premenstrual syndrome (PMS) as well as other menstrual, day of week, and lunar cyclicity. Volunteer participants from the community (60 women and 10 men) provided daily data for 12 to 18 weeks. Significant mood fluctuation was determined by a new nonparametric method using each individual's own standard deviation as a measure of marked change. Cyclicity was the norm; two thirds of both the women and men had one or more menstrual or lunar phases or days of the week that were markedly positive and/or negative, relative to their own range, but few experienced stereotypical cyclicity (PMS, Monday blues, full moon). About half the women whose prospective data met conservative criteria for PMS, met liberal criteria, or met neither criteria said they had PMS, and half in each group said they did not.  相似文献   
132.
Most research on lesbians has used self-report questionnaires, and assumed that respondents who complete a lesbian questionnaire self-identify as lesbians and engage in sexual relationships with women. The present study examined the degree to which 2,393 women who answered a Lesbian Wellness Survey are distributed on five aspects of lesbian sexuality and the coming-out process. The five aspects were: (a) Sexual Orientation (numerical rating of sexual identity from exclusively lesbian/gay to exclusively heterosexual); (b) Years Out (length of time of self-identity as lesbian/gay/bisexual); (c) Outness/Disclosure (amount of disclosure of sexual orientation to others); (d) Sexual Experience (proportion of sexual relationships with women); and (e) Lesbian Activities (extent of participation in lesbian community events). Mild but significant correlations were found among these dimensions, indicating that being lesbian is not a homogeneous experience. Closer examination by the demographic characteristics of race/ethnicity and age revealed a diversity of experience. African American, Native American, and Latina respondents had moderate correlations among these aspects of lesbian experience, whereas White and Asian American respondents evidenced only mild or nonsignificant correlations. The results indicate that researchers who are studying one aspect of the lesbian experience (e.g., outness to others) need to ensure that they are not assuming such behavior based on other dimensions (such as frequent participation in lesbian community activities or years of being out), especially among White and Asian American lesbians.  相似文献   
133.
134.
The study examined whether relationships with extended kin were related to higher levels of mental health and academic functioning among college students. Specifically, the study tested whether perceived emotional support from extended (non-nuclear) family was related to self-esteem, psychological distress, and academic efficacy and dedication above and beyond relationships with one’s primary caregivers, and whether these associations varied by class year in college. The sample consisted of 530 students (average age = 20.82), at a public, four-year university. The results revealed that freshmen and seniors who reported high levels of positive relationships with their extended kin also reported higher levels of academic-efficacy and dedication, as well as lower levels of psychological distress. However, the relation between kin emotional support and these outcomes were not significant for sophomores and juniors. There was also a significant association between kinship support and self-esteem for participants in all four class levels. The study underscores the need to examine extended social support systems among college students, above and beyond those maintained with primary caregivers, as well as the dynamic nature of family support during young adulthood.  相似文献   
135.
The AGM theory of belief revision provides a formal framework to represent the dynamics of epistemic states. In this framework, the beliefs of the agent are usually represented as logical formulas while the change operations are constrained by rationality postulates. In the original proposal, the logic underlying the reasoning was supposed to be supraclassical, among other properties. In this paper, we present some of the existing work in adapting the AGM theory for non-classical logics and discuss their interconnections and what is still missing for each approach.  相似文献   
136.
The type of experience involved with an object category has been regarded as one important factor in shaping of the human object recognition system. Laboratory training studies have shown that different kinds of learning experience with the same set of novel objects resulted in different perceptual and neural changes. Whether this applies to natural real-world objects remains to be seen. We compared two groups of observers who had different learning experiences with faces, using holistic processing as a dependent measure. We found that, while ordinary observers had extensive individuation experience with faces and displayed typical holistic face processing, art students who had acquired additional experience in drawing faces, and thus in attending to parts of a face, showed less holistic processing than did ordinary observers. These results converge with laboratory training studies on the role of type of experience in the development of different perceptual markers for different object categories. It is thus insufficient to categorize expertise simply in terms of object domains (e.g., expertise with faces). Instead, perceptual expertise should be classified in terms of the underlying process or task demand.  相似文献   
137.

Purpose

The purpose of this study was to investigate the conditional effects of power values diversity and relationship conflict.

Design/Methodology/Approach

We utilized a time-lagged survey design and multilevel modeling to investigate 60 teams working on a project task over the course of 4 months.

Findings

When participative safety climate was high, the presence of high power values diversity was particularly helpful for reducing relationship conflict. In turn, decreased relationship conflict tended to increase team performance. Additionally, when workload sharing was low, high relationship conflict was especially harmful to team performance.

Implications

Results support the consideration of team participative safety climate to better understand the conditions under which power values diversity is likely to lessen relationship conflict and subsequently increase team performance. Findings also highlight the importance of avoiding low workload sharing, in the presence of prominent relationship conflict, to increase team performance.

Originality/Value

By examining relationship conflict as a mediator and participative safety climate as a moderator of power values diversity’s effects, we make a novel contribution to extant literature by helping to elucidate both how and under what conditions differences in power values, among team members, can influence team performance. Relatedly, we answer the call for more research that adopts a contingency approach toward examining the effects of values diversity and relationship conflict. In doing so, we help to identify the conditions under which power values diversity and relationship conflict are likely to differentially influence important team outcomes.
  相似文献   
138.
This study examined family members’ opinions regarding their family quality of life (FQOL). Parents (n = 97) and youngsters (n = 24) of 63 families with a child with an intellectual disability (ID) receiving home-based support completed the Beach Center FQOL Scale. Multilevel models detected substantial variability in FQOL scores and in most subscale scores both within and between families. The observed differences were partly explained by the respondent’s age, the parents’ employment situation, and the support needs of the child with an ID. Role of the family member and gender of the parent could not explain this variability. By including and comparing multiple family members’ opinions, this study contributes to the methodological and conceptual discussions about measuring FQOL.  相似文献   
139.
Using a speeded retrieval procedure, we investigated time-of-day effects in automatic and controlled retrieval. Morning-type adults were tested at either peak (early morning) or off-peak (late afternoon) times on a speeded implicit (Experiment 1) or explicit (Experiment 2) stem completion task. In Experiment 1, retrieval strategies were identified by changes in response speed between a practice phase with rapid retrieval and an implicit memory test phase. Performance based on controlled retrieval (shown by slowdown participants) showed more priming at peak than at off-peak times of day, a finding confirmed in Experiment 2, in which the participants were given intentional retrieval instructions when the materials switched. In contrast, performance based on automatic retrieval (shown by nonslowdown participants) did not differ across peak and off-peak times. The finding suggests a robust synchrony effect in controlled retrieval, but not in automatic retrieval, which does not appear to vary across the day.  相似文献   
140.
Behavioural flexibility allows animals to adjust their behaviours according to changing environmental demands. Such flexibility is frequently assessed by the discrimination–reversal learning task. We examined grey squirrels’ behavioural flexibility, using a simultaneous colour discrimination–reversal learning task on a touch screen. Squirrels were trained to select their non-preferred colour in the discrimination phase, and their preferred colour was rewarded in a subsequent reversal phase. We used error rates to divide learning in each phase into three stages (perseveration, chance level and ‘learned’) and examined response inhibition and head-switching during each stage. We found consistent behavioural patterns were associated with each learning stage: in the perseveration stage, at the beginning of each training phase, squirrels showed comparable response latencies to correct and incorrect stimuli, along with a low level of head-switching. They quickly overcame perseveration, typically in one to three training blocks. In the chance-level stage, response latencies to both stimuli were low, but during initial discrimination squirrels showed more head-switches than in the previous stage. This suggests that squirrels were learning the current reward contingency by responding rapidly to a stimulus, but with increased attention to both stimuli. In the learned stage, response latencies to the correct stimulus and the number of head-switches were at their highest, whereas incorrect response latencies were at their lowest, and differed significantly from correct response latencies. These results suggest increased response inhibition and attention allowed the squirrels to minimise errors. They also suggest that errors in the ‘learned’ stage were related to impulsive emission of the pre-potent or previously learned responses.  相似文献   
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