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501.
Results are presented for suitability screening conducted by the United States Air Force during basic military training. The Lackland Behavioral Questionnaire has been used operationally since 2007, and its use has led to an increase in predictive validity. For the prediction of outcomes during the first 4 years of service, one can identify trainees with a 49% likelihood of being separated for unsuitability and a 56% likelihood of being diagnosed with a mental disorder. A formal suitability screening program allows referrals and recommendations to be made using a combination of empirical evidence and clinical judgment.  相似文献   
502.
This paper describes the damage features generated by the high-velocity impact of diamond particles on diamond produced by chemical vapour deposition (CVD). Two types of diamond grit - angular and cubo-octahedral - were used to impact the surface of the diamond target at a mean impact velocity of 268?m?s?1. The main damage features were elastic-plastic radial and lateral cracks. Distorted Hertzian ring cracks were also seen on samples impacted with cubo-octahedral diamond grit. This indicates that, in contrast to previous experiments by the authors using silica sand erodent, Hertzian damage can be generated at this velocity when the mechanical properties of the erodent and target are comparable. Fragmentation of the diamond grit occurred on impact; however, the extent of the degradation was much reduced compared with the silica sand erodent.  相似文献   
503.
Nicholls et al. (1999, Proc. Royal Soc. B, 266, 1517-1522) demonstrated that models turn their left or right cheeks when expressing or concealing emotion, respectively. This study examined whether emotionally expressive individuals are more likely to turn their left cheek when posing for a photograph than less emotionally expressive individuals. One hundred twenty-four normal participants completed an Emotional Expressivity Scale (EES) and posed for a photograph. Females had a higher EES than males and there was a trend for left cheek posers to have a higher EES than right cheek posers. Females were more likely to turn their left cheek than were males. Results support our argument that emotionally expressive individuals turn their left cheek when posing. The higher incidence of leftward poses in females than males may reflect the higher EES for females. These results support the proposition that the leftward bias in painted portraits is related to a desire to capture the emotive qualities of the left side of the face.  相似文献   
504.
How does visual long-term memory store representations of different entities (e.g., objects, actions, and scenes) that are present in the same visual event? Are the different entities stored as an integrated representation in memory, or are they stored separately? To address this question, we asked observers to view a large number of events; in each event, an action was performed within a scene. Afterward, the participants were shown pairs of action–scene sets and indicated which of the two they had seen. When the task required recognizing the individual actions and scenes, performance was high (80 %). Conversely, when the task required remembering which actions had occurred within which scenes, performance was significantly lower (59 %). We observed this dissociation between memory for individual entities and memory for entity bindings across multiple testing conditions and presentation durations. These experiments indicate that visual long-term memory stores information about actions and information about scenes separately from one another, even when an action and scene were observed together in the same visual event. These findings also highlight an important limitation of human memory: Situations that require remembering actions and scenes as integrated events (e.g., eyewitness testimony) may be particularly vulnerable to memory errors.  相似文献   
505.
Academic scholarship on teen television programs indicates that images of queer sexualities can strongly impact the identities of emerging adults. Yet what is missing from this body of scholarship is an in-depth examination of how these representations are incorporated into the identity projects of the emerging adults who watch these shows. This study fills this gap by examining qualitative interviews with emerging adults who watch Glee. The participants consistently and overwhelmingly identified Glee as representing “progressive” emerging adult sexuality. Within that, three key themes emerged. First, identifying with Glee is a gendered practice. Second, Glee fandom aligns with an affinity for musical theater, which is traditionally considered a mirror for gay culture. Finally, while viewers recognized queer narrative content, it did not produce a broader acceptance of non-heterosexual identities. Viewers normalized their own (real, straight) identities in relation to the (fake, queer) identities shown in the narrative.  相似文献   
506.
The N-methyl-D-aspartate receptor (NMDAR) is thought to be essential for synaptic plasticity and learning. However, recent work indicates that the role of this receptor depends on the prior history of the research subject. For example, animals trained on a hippocampus-dependent learning task are subsequently able to acquire new information in the absence of NMDAR activation. The current experiments were designed to identify the types of experiences that lead to NMDAR-independent learning. Using contextual fear conditioning in mice, we find that NMDAR-independent learning is only observed when (1) animals are trained on the same behavioral task and (2) initial learning is successfully encoded into long-term memory.  相似文献   
507.
508.
Learning is ubiquitous in the animal kingdom but has been studied extensively in only a handful of species. Moreover, learning studied under laboratory conditions is typically unrelated to the animal's natural environment or life history. Here, we designed a task relevant to the natural behavior of male African cichlid fish (Astatotilapia burtoni), to determine if they could be trained on a spatial task to gain access to females and shelter. We measured both how successfully animals completed this task over time and whether and how immediate early gene and hormone expression profiles were related to success. While training fish in a maze, we measured time to task completion, circulating levels of three key hormones (cortisol, 11-ketotestosterone, and testosterone) and mRNA abundance of seven target genes including three immediate early genes (that served proxies for brain activity) in nine brain regions. Data from our subjects fell naturally into three phenotypes: fish that could be trained (learners), fish that could not be trained (non-learners) and fish that never attempted the task (non-attempters). Learners and non-learners had lower levels of circulating cortisol compared to fish that never attempted the task. Learners had the highest immediate early gene mRNA levels in the homologue of the hippocampus (dorsolateral telencephalon; Dl), lower cortisol (stress) levels and were more motivated to accomplish the task as measured by behavioral observations. Fish that never attempted the task showed the lowest activity within the Dl, high stress levels and little to no apparent motivation. Data from non-learners fell between these two extremes in behavior, stress, and motivation.  相似文献   
509.
Modeling activity-based anorexia, food-deprived rats consistently show that activity increases as weight decreases. This effect was explored in 8 food-deprived, Sprague-Dawley rats as potentially mediated by intrinsic value of activity. Running-wheel activity rates were recorded for free-fed weight, reduction to 90% of free-fed weight, and to 80% of free-fed weight. As expected, activity increased as weight decreased. Further, significant differences appeared in the trends of individual run rates when compared across all trials. These individual trends were expressed as varied rates of running, with extreme high and low run rates prevalent. The rewarding nature of exercise itself might serve to predict these trends in individual rats and reveal potential indicators for the development of activity-based anorexia.  相似文献   
510.
Perceptions of defeat have been linked to a range of clinical disorders including psychosis. Perceived defeat sometimes increases in response to failure, but the strength of this association varies between individuals. The present research investigated whether trait reappraisal, a thought-focused coping style, amplified response to stressful events. Two studies (Study 1, n = 120 nonclinical participants; Study 2, n = 77 participants with schizophrenia-spectrum disorders) investigated whether trait reappraisal amplified feelings of defeat following an experience of failure versus success. Frequent reappraisers showed the largest increases in subjective defeat after failure versus success in both studies, with nonclinical participants with greater habitual reappraisal also showing larger increases in sadness and general negative affect. Frequent use of reappraisal may confer vulnerability to subjective defeat in response to stressful life events among nonclinical and clinical populations and could be an area for relapse prevention interventions to target.  相似文献   
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