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911.
We propose and test a comprehensive theory designed to explain seemingly contradictory relations between job demands, emotional exhaustion, and work‐family conflict (WFC) reported in the literature. Using job demands‐resources theory, effort‐recovery theory, and personal resources theory we hypothesized that job demands would spillover to emotional exhaustion as mediated by WFC (causality model), and alternatively that job demands would also spillover to WFC as mediated by emotional exhaustion (reverse causal model). Further, we also hypothesized using loss spiral theory that a more comprehensive model representing reciprocal and cross‐linked effects (causal and reverse causal simultaneously) would best fit the data. The hypotheses were tested in a longitudinal study of 257 Australian (Victorian) frontline police officers at two time points approximately 12 months apart. We used structural equation modelling and found in support of the simultaneous reciprocal effects hypothesis, that the more comprehensive model fitted the data better than either the causality or the reverse causal model. Future research should more comprehensively model the important relationships between job demands, emotional exhaustion, and WFC to reflect their complex interplay. Interventions to reduce work demands arising from work pressure and emotional demands are indicated to prevent conflict at home and emotional exhaustion in police officers.  相似文献   
912.
Speech sounds are highly variable, yet listeners readily extract information from them and transform continuous acoustic signals into meaningful categories during language comprehension. A central question is whether perceptual encoding captures acoustic detail in a one-to-one fashion or whether it is affected by phonological categories. We addressed this question in an event-related potential (ERP) experiment in which listeners categorized spoken words that varied along a continuous acoustic dimension (voice-onset time, or VOT) in an auditory oddball task. We found that VOT effects were present through a late stage of perceptual processing (N1 component, ~100 ms poststimulus) and were independent of categorization. In addition, effects of within-category differences in VOT were present at a postperceptual categorization stage (P3 component, ~450 ms poststimulus). Thus, at perceptual levels, acoustic information is encoded continuously, independently of phonological information. Further, at phonological levels, fine-grained acoustic differences are preserved along with category information.  相似文献   
913.
Given the polarization of the early 21st century political atmosphere in the U.S., intergroup dialogue has emerged as a unique alternative setting, with intentions of facilitating a more productive and thoughtful citizen engagement. Although cross‐partisan dialogue efforts are underway in community contexts, they have been slower to reach academic settings. This paper is an exploratory study of our own liberal‐conservative dialogue course at the University of Illinois–the first of its kind, to our knowledge. After describing basic features of the course, we identify themes from student journals and final evaluations suggesting both dialogue benefits and challenges. Finally, we discuss the growing literature around dialogue, questions of its long‐term impact, and larger potential barriers to participation in liberal‐conservative dialogue, specifically. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
914.
915.
Six pigeons were trained in a change detection task with four colors. They were shown two colored circles on a sample array, followed by a test array with the color of one circle changed. The pigeons learned to choose the changed color and transferred their performance to four unfamiliar colors, suggesting that they had learned a generalized concept of color change. They also transferred performance to test delays several times their 50-msec training delay without prior delay training. The accurate delay performance of several seconds suggests that their change detection was memory based, as opposed to a perceptual attentional capture process. These experiments are the first to show that an animal species (pigeons, in this case) can learn a change detection task identical to ones used to test human memory, thereby providing the possibility of directly comparing short-term memory processing across species.  相似文献   
916.
Activation of the infralimbic region (IL) of the medial prefrontal cortex (mPFC) reduces conditioned fear in a variety of situations, and the IL is thought to play an important role in the extinction of conditioned fear. Here we report a series of experiments using contextual fear conditioning in which the IL is activated with the GABAa antagonist picrotoxin (Ptx) during a single extinction session in the fear context. We investigate the impact of this manipulation on subsequent extinction sessions in which Ptx is no longer present. First, we demonstrate that a single treatment with intra-IL Ptx administered in a conditioned fear context greatly accelerates the rate of extinction on the following days. Importantly, IL-Ptx also enhances extinction to a different fear context than the one in which IL-Ptx was administered. Thus, IL-Ptx primes extinction learning regardless of the fear context in which the IL was initially activated. Second, activation of the IL must occur in conjunction with a fear context in order to enhance extinction; the extinction enhancing effect is not observable if IL-Ptx is administered in a neutral context. Finally, this extinction enhancing effect is specific to the IL for it does not occur if Ptx is injected into the prelimbic region (PL) of the mPFC. The results indicate a novel persisting control of fear induced by activation of the IL and suggest that IL activation induces changes in extinction-related circuitry that prime extinction learning.  相似文献   
917.
The AT4 ligands, angiotensin IV and LVV-hemorphin 7, elicit robust effects on facilitating memory by binding to a specific site in the brain historically termed the angiotensin AT4 receptor. The identification of the AT4 receptor as insulin-regulated aminopeptidase (IRAP) is controversial, with other proteins speculated to be the target(s) of these peptides. In this study we have utilized IRAP knockout mice to investigate IRAP in the brain. We demonstrate that the high-affinity binding site for angiotensin IV is absent in IRAP knockout mice brain sections in parallel with the loss of IRAP immunostaining, providing irrefutable proof that IRAP is the specific high-affinity binding site for AT4 ligands. However, our characterization of the behavioural phenotype of the IRAP knockout mice revealed a totally unexpected finding. In contrast to the acute effects of IRAP inhibitors in enhancing memory, deletion of the IRAP gene resulted in mice with an accelerated, age-related decline in spatial memory that was only detected in the Y maze paradigm. Moreover, no alterations in behaviour of the IRAP knockout mice were observed that could assist in elucidating the endogenous substrate(s). Our results highlight the importance of analysing the behavioural phenotype of knockout mice across different ages and in distinct memory paradigms.  相似文献   
918.
We examined the structural, discriminant, nomological, and incremental predictive validity of a behavioral measure of emotional intelligence, using data from two undergraduate student samples. Covariance structure modeling indicated that the eight subscales of the MSCEIT© V2.0 were best modeled with a solution consisting of three first-order factors, and supported the existence of one higher-order factor of overall emotional intelligence. Multi-group confirmatory factor analyses indicated that the higher-order factor had discriminant validity from personality and conformity. Contrary to prediction, the higher-order factor was more highly correlated to social desirability than to general mental ability or long term affect. Finally, hierarchical regression results indicated that overall emotional intelligence did not predict incremental variance in either GPA or life satisfaction.  相似文献   
919.
Two decades ago, Alexander George observed a growing gap between academic theorists and practitioners in the formulation of foreign policy. The significance of the gap has been debated, but trends in the academy, society, and government suggest it is likely to grow.  相似文献   
920.
CONTEXT: Alcohol use is frequently identified as a contributor to risky sexual behaviors; however, research results are mixed. Given the conflicting evidence, researchers have focused on other factors, such as expectations about alcohol's effects that might help explain the relationship of alcohol use and risky sexual behaviors. METHODS: Cross-sectional data from 312 sexually experienced males aged 18-30 in a shantytown in Lima, Peru, were used in logistic regression models to identify associations of heavy episodic drinking and sex-related expectations about alcohol with sexual risk behaviors. RESULTS: Heavy episodic drinking was associated with having had two or more sexual partners and having had sex with a casual partner in the past year (odds ratios, 2.8 and 2.5, respectively). After controlling for alcohol consumption, sex-related expectations about alcohol were associated with these high-risk sexual behaviors, as well as with not using a condom at last sex (1.2) and not using a condom at last sex with a casual partner (1.3). CONCLUSION: Beliefs about the effect of alcohol on sexual performance could help explain links between alcohol consumption and risky sexual behavior not completely accounted for by the pharmacological effects of alcohol.  相似文献   
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