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1.
《Acta Metallurgica》1982,30(4):881-887
Several deformation mechanisms have been proposed to explain the flow process of Harper-Dorn creep. The implications of these various mechanisms are compared with the available experimental data, and it is concluded that flow occurs by the climb of edge dislocations under saturated conditions. Using the theoretical model for this process, it is possible to specify the experimental criteria for observations of Harper-Dorn creep in terms of the upper limiting stress and the lower limiting grain size.  相似文献   

2.
Previous researchers have proposed that the time and energy involved in family and paid work should affect the relationship between stressors and conflict in both the work and family domains. Using a sample of 113 registered nurses, the authors hypothesized that the amount of time and involvement in both domains would moderate the stressor–conflict relationships. Results supported many of the interactions in predicting conflict in each domain, and implications for the health of working women with family responsibilities were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
Objective: This article examines the impact of a universal social–emotional learning program, the Fast Track PATHS (Promoting Alternative Thinking Strategies) curriculum and teacher consultation, embedded within the Fast Track selective prevention model. Method: The longitudinal analysis involved 2,937 children of multiple ethnicities who remained in the same intervention or control schools for Grades 1, 2, and 3. The study involved a clustered randomized controlled trial involving sets of schools randomized within 3 U.S. locations. Measures assessed teacher and peer reports of aggression, hyperactive–disruptive behaviors, and social competence. Beginning in first grade and through 3 successive years, teachers received training and support and implemented the PATHS curriculum in their classrooms. Results: The study examined the main effects of intervention as well as how outcomes were affected by characteristics of the child (baseline level of problem behavior, gender) and by the school environment (student poverty). Modest positive effects of sustained program exposure included reduced aggression and increased prosocial behavior (according to both teacher and peer report) and improved academic engagement (according to teacher report). Peer report effects were moderated by gender, with significant effects only for boys. Most intervention effects were moderated by school environment, with effects stronger in less disadvantaged schools, and effects on aggression were larger in students who showed higher baseline levels of aggression. Conclusions: A major implication of the findings is that well-implemented multiyear social–emotional learning programs can have significant and meaningful preventive effects on the population-level rates of aggression, social competence, and academic engagement in the elementary school years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
The present experiments tested the effects of conventional (dorsal aspiration and electrolytic) and excitotoxic (N-methyl-{d}-aspartate [NMDA]) hippocampal lesions and fimbria-fornix (FF) transection on prepulse inhibition (PPI) of startle response and on open-field activity. Activity was increased by FF transection and by conventional but not excitotoxic hippocampal lesions; complete NMDA lesion increased amphetamine-induced activity. Whereas dorsal hippocampal aspiration lesion disrupted PPI, the phenomenon was not affected by dorsal hippocampal. electrolytic lesion, partial or complete excitotoxic (NMDA) hippocampal lesions, or complete FF transection, which interrupted the cholinergic input to the hippocampus as well as the hippocampal-subicular input to the nucleus accumbens. Systemic apomorphine disrupted PPI in both FF-transected rats and their controls. It is suggested that the hippocampus is essential for PPI disruption rather than for PPI expression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
Objective: This study evaluated and compared several methods of assessing daily cigarette consumption. Design: Comparison of measures of daily cigarette consumption from several sources, from 232 smokers entering a smoking cessation program. Main Outcome Measures: Global reports of average smoking, Time-Line Follow-Back (TLFB) recall for the week preceding the study (premonitoring TLFB), 2 weeks' cigarette recordings using electronic diaries and ecological momentary assessment (EMA), and TLFB recall of smoking during EMA (monitored TLFB). Results: Global reports and premonitoring TLFB showed severe digit bias: six times as many values as expected were rounded at 10. Monitored TLFB also showed substantial digit bias (four times). EMA data showed none. EMA averaged 2.6 cigarettes lower than monitored TLFB, but exceeded TLFB on 32% of days. Across days, EMA and TLFB only correlated 0.29. Daily variations in TLFB did not correlate with variations in carbon monoxide (CO) measures taken on 3 days, but EMA measures did; among participants whose CO varied, r = .69. CO correlated with EMA cigarettes recorded in the preceding 2 hours, suggesting timely recording of cigarettes. Conclusion: TLFB measures are limited for precise assessment of cigarette consumption. EMA measures appear to be useful for tracking smoking, and likely other health-relevant events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
We evaluated age-related differences in the optimality of decision boundary settings in a diffusion model analysis. In the model, the width of the decision boundary represents the amount of evidence that must accumulate in favor of a response alternative before a decision is made. Wide boundaries lead to slow but accurate responding, and narrow boundaries lead to fast but inaccurate responding. There is a single value of boundary separation that produces the most correct answers in a given period of time, and we refer to this value as the reward rate optimal boundary (RROB). We consistently found across a variety of decision tasks that older adults used boundaries that were much wider than the RROB value. Young adults used boundaries that were closer to the RROB value, although age differences in optimality were smaller with instructions emphasizing speed than with instructions emphasizing accuracy. Young adults adjusted their boundary settings to more closely approach the RROB value when they were provided with accuracy feedback and extensive practice. Older participants showed no evidence of making boundary adjustments in response to feedback or task practice, and they consistently used boundary separation values that produced accuracy levels that were near asymptote. Our results suggest that young adults attempt to balance speed and accuracy to achieve the most correct answers per unit time, whereas older adultts attempt to minimize errors even if they must respond quite slowly to do so. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
In the current study, we conducted daily telephone interviews with a sample of Chinese workers (N = 57) for 5 weeks to examine relationships between daily work–family conflict and alcohol use. Drawn from the tension reduction theory and the stressor–vulnerability model, daily work–family conflict variables were hypothesized to predict employees’ daily alcohol use. Further, social variables (i.e., peer drinking norms, family support, and coworker support) were hypothesized to moderate the relationship between work–family conflict and alcohol use. Results showed that daily work-to-family conflict but not family-to-work conflict had a significant within-subject main effect on daily alcohol use. In addition, there was significant between-subject variation in the relationship between work-to-family conflict and alcohol use, which was predicted by peer drinking norms, coworker support, and family support. The current findings shed light on the daily health behavior consequences of work–family conflict and provide important theoretical and practical implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
This article provides an analysis of the techniques, methods, materials, and discourses of child study observation to illuminate its role in the sociohistorical colonization of childhood. Through analysis of key texts it explains how early 20th-century child study provided for the transcendence of historical, racial, and social contexts for understanding human development. The colonizing project of child study promoted the advancement of Eurocentric culture through a generic “White” development. What a child is and can be, and the meaning of childhood has been disembodied through observation, record keeping, and analytical processes in which time and space are abstracted from behavior, and development symbolized as a universal ideal. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

9.
Perceptions of work interfering with family life and family issues interfering with work are examined as 2 distinct constructs representing work–family conflict. Experienced work–family conflict is argued to reduce one's value attainment which, in turn, lowers both job and life satisfaction. This study examines value attainment as a mediating variable in the work–family conflict and satisfaction relationship. Responses from 270 hotel managers indicate that value attainment either partially or fully mediates the relationship between work interference with family and family interference with work and both job and life satisfaction. Value attainment is argued to be a meaningful explanatory variable for the negative relationship between work–family conflict and job–life satisfaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
Studied the effects of concreteness and relatedness of adjective–noun pairs on free recall, cued recall, and memory integration. The authors report on 2 experiments in which Ss read phrases or sentences containing adjective–noun pairs that vary in rated concreteness and intrapair relatedness. In Exp 1 normative ratings on imagery and relatedness were provided by 23 graduate and 20 undergraduate students. 64 undergraduates participated in the memory experiment. Exp 2 extended Exp 1 by using complete sentences rather than adjective–noun word pairs. 72 undergraduates volunteered to participate in the memory experiment and a separate group of 14 volunteered to participate in a sentence rating task. Consistent with predictions from dual coding theory and prior results with noun–noun pairs, both experiments showed that the effects of concreteness were strong and independent of relatedness in free recall and cued recall. The 2 attributes also had independent (additive) effects on integrative memory as measured by conditionalized free recall of pairs. Integration as measured by the increment from free to cued recall occurred consistently only when pairs were high in both concreteness and relatedness. Relatedness, adjective imagery, and noun imagery ratings, along with word frequencies for adjectives and nouns, and sentences with relatedness ratings are appended. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
Objective:This report extends earlier accounts by addressing the effects of the Strong African American Families (SAAF) program across 65 months. Two hypotheses were tested: (a) Rural African American youths randomly assigned to participate in SAAF would demonstrate lower rates of alcohol use than would control youths more than 5 years later, and (b) SAAF’s effects on deterring the onset of alcohol use in early adolescence would carry forward to mediate the program’s long-term effects. Method: African American youths in rural Georgia (mean age at pretest = 10.8 years) were assigned randomly to the SAAF group (n = 369) or to a control group (n = 298). Past-month alcohol use was assessed at pretest and at 9, 18, 29, 53, and 65 months after pretest. Results: SAAF participants increased their alcohol use at a slower rate than did adolescents in the control condition across the follow-up assessments. At the 65-month assessment, SAAF participants reported having drunk alcohol half as often as did youths in the control group. Consistent with the second hypothesis, SAAF’s effects on deterring initiation carried forward to account for its effects on alcohol use across time. Conclusions: Training in protective parenting processes and self-regulatory skills during preadolescence may contribute to a self-sustaining trajectory of disinterest in and avoidance of alcohol use during adolescence when peers begin to model and sanction it. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
R. M. Nosofsky and T. J. Palmeri's (1997) exemplar-based random-walk (EBRW) model of speeded classification is extended to account for speeded same–different judgments among integral-dimension stimuli. According to the model, an important component process of same–different judgments is that people store individual examples of experienced same and different pairs of objects in memory. These exemplar pairs are retrieved from memory on the basis of how similar they are to a currently presented pair of objects. The retrieved pairs drive a random-walk process for making same–different decisions. The EBRW predicts correctly that same responses are faster for objects lying in isolated than in dense regions of similarity space. The model also predicts correctly effects of same-identity versus same-category instructions and is sensitive to observers' past experiences with specific same and different pairs of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
A cognitive–behavioral conceptualization of depression is presented, identifying distorted perceptions, ineffective actions, and/or an unresponsive environment as possible causative factors. Acknowledging that information about a patient’s early history can inform the cognitive–behavior therapist about possible areas of vulnerability that are triggered by current life events, a transtheoretical case formulation model is presented and illustrated for the case of David. The case formulation highlights the intrapersonal and interpersonal issues that should be the focus of the therapeutic intervention, and an integrated cognitive–behavioral intervention that follows from this formulation is described. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
Reports an error in "The MMPI-2 Restructured Clinical Scales in the assessment of posttraumatic stress disorder and comorbid disorders" by Erika J. Wolf, Mark W. Miller, Robert J. Orazem, Mariann R. Weierich, Diane T. Castillo, Jaime Milford, Danny G. Kaloupek and Terence M. Keane (Psychological Assessment, 2008[Dec], Vol 20[4], 327-340). The URL for the supplemental material was incomplete. The complete URL is http://dx.doi.org/10.1037/a0012948.supp (The following abstract of the original article appeared in record 2008-17693-002.) This study examined the psychometric properties of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) Restructured Clinical Scales (RCSs) in individuals with posttraumatic stress disorder (PTSD) receiving clinical services at Department of Veterans Affairs medical centers. Study 1 included 1,098 men who completed the MMPI-2 and were assessed for a range of psychological disorders via structured clinical interview. Study 2 included 136 women who completed the MMPI-2 and were interviewed with the Clinician Administered Scale for PTSD. The utility of the RCSs was compared with that of the Clinical Scales (CSs) and the Keane PTSD (PK) scale. The RCSs demonstrated good psychometric properties and patterns of associations with other measures of psychopathology that corresponded to current theory regarding the structure of comorbidity. A notable advantage of the RCSs compared with the MMPI-2 CSs was their enhanced construct validity and clinical utility in the assessment of comorbid internalizing and externalizing psychopathology. The PK scale demonstrated incremental validity in the prediction of PTSD beyond that of the RCSs or CSs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
The leader–member exchange (LMX) literature has established that leaders differentiate among their followers. Yet little is known about the effects of LMX differentiation (within-group variation in LMX quality). In this study, we contend that the effects of LMX differentiation on the employee outcomes of work attitudes, coworker relations, and employee withdrawal behaviors will be contingent upon the level of procedural and distributive justice climate. Data from 276 employees working in 25 stores of a retail chain in Turkey supported our hypotheses such that LMX differentiation was related to more negative work attitudes and coworker relations, and higher levels of withdrawal behaviors only when justice climate was low. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Accumulating evidence suggests that particular kinds of dysfunctional beliefs contribute to obsessive–compulsive (OC) symptoms. Three domains of beliefs have been identified: (a) perfectionism and intolerance of uncertainty, (b) overimportance of thoughts and the need to control thoughts, and (c) inflated responsibility and overestimation of threat. These beliefs and OC symptoms are both heritable. Although it is widely acknowledged that OC symptoms probably have a complex biopsychosocial etiology, to our knowledge there has been no previous attempt to integrate dysfunctional beliefs and genetic factors into a unified, empirically supported model. The present study was an initial step in that direction. A community sample of monozygotic and dizygotic twins (N = 307 pairs) completed measures of dysfunctional beliefs and OC symptoms. Structural equation modeling was used to compare 3 models: (a) the belief causation model, in which genetic and environmental factors influence beliefs and OC symptoms, and beliefs also influence symptoms; (b) the symptom causation model, which is the same as (a) except that symptoms cause beliefs; and (c) the belief coeffect model, in which beliefs and OC symptoms are the product of common genetic and environmental factors, and beliefs have no causal influence on symptoms. The belief causation model was the best fitting model. Beliefs accounted for a mean of 18% of phenotypic variance in OC symptoms. Genetic and environmental factors, respectively, accounted for an additional 36% and 47% of phenotypic variance. The results suggest that further biopsychosocial investigations may be fruitful for unraveling the etiology of obsessions and compulsions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
This study of 62 dyads of employees (N = 124) examined the crossover of work engagement—a positive, fulfilling, work-related state of mind that is characterized by vigor, dedication, and absorption. We hypothesized that work engagement crosses over from an employee (the actor) to his or her colleague (the partner) on a daily basis. The frequency of daily communication was expected to moderate the crossover of daily work engagement, which in turn would relate to colleagues’ daily performance. Participants first filled in a general questionnaire and then completed a diary study over 5 consecutive workdays. The hypotheses were tested with multilevel analyses, using an actor–partner interdependence model. Results confirmed the crossover of daily work engagement, but only on days when employees within a dyad interacted more frequently than usual. Moreover, we found that actor’s work engagement (particularly vigor), when frequently communicated, had a positive indirect relationship with partner’s performance through partner’s work engagement. Finally, results showed that actor’s vigor was negatively related to partner’s performance when communication was low. However, this negative effect was counteracted when mediated by the vigor of the partner. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
The structure of the Outcome Questionnaire–45 (Lambert et al., 2001) was examined in a sample of 1,100 university counseling center clients using confirmatory factor analysis. Specifically, the relative fit of 1-factor, 3-factor orthogonal, 3-factor oblique, 4-factor hierarchical, and 4-factor bilevel models were examined. Although the 3-factor oblique, 4-factor hierarchical, and 4-factor bilevel models fit the data well, the 4-factor bilevel model fit the data best. The results provided support for the fit of the 4-factor bilevel model where each item loads on 1 of the 3 independent scales of Symptom Distress, Social Role Performance, and Interpersonal Relations, in addition to a nonoverlapping general distress factor. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Consistent with the proposal that people rely on implicit causal theories that relate different types of attributions to behaviors that differ in valence, 3 studies showed that in addition to predicting more positive than negative behavior in the target, participants produced an attribution–prediction bias. This bias indicated that persons with a dispositional orientation predicted more negative and less positive behavior from the target than persons with a situational orientation. The authors produced these findings in Studies 1 and 2 by manipulating the perceived characteristic motives of a target (dispositional, situational). In Study 3 the authors used a cultural operationalization of attributional orientations by examining the responses of Western students (dispositionalists) and East Asian students (situationalists). Finally, in support of the underlying mechanism, Study 4 showed that activating dispositional or situational knowledge facilitated the encoding of negative and positive behaviors, respectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
Discriminating same from different collections of items is central to human thought and reasoning. Recent comparative research suggests that same–different discrimination behavior is not uniquely human, does not require human language, is based on the variability of the collection of items, obeys fundamental psychophysical laws, and may be captured by quantitative models of the stimulus collection. The comparative study of same–different discrimination behavior sheds fresh light on the mechanisms and functions of abstract conceptualization. This study also has prompted the development of a theory—the Finding Differences Model—that successfully explains a wealth of findings in the comparative psychology of same–different discrimination behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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