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71.
Work on the genetic region of the house mice known as the t-complex has produced the hypothesis that mice heterozygous for t-haplotypes (+/t) may have a selective advantage over wild-type (+/+) males owing to the greater aggressiveness of +/t males. We tested this hypothesis by examining the behavior of +/+ and +/t mice placed in four large outdoor enclosures. We found that +/t males were dominant over +/+ males. Furthermore, in the outdoor enclosures +/t males had higher survivorship than +/+ males, both as adults and juveniles. However, males of the two genotypes did not differ in home range size. We suggest that t-haplotypes may be, in part, maintained in mouse populations because of a selective advantage in heterozygous males. © 1996 Wiley-Liss, Inc.  相似文献   
72.
This paper seeks to move beyond what Martin and Ruhs described as the numbers versus rights equation in temporary labour migration programs. We do this by examining the ideology of temporary labour migration. This ideology has three key elements: temporariness, labour markets and rights. The paper describes how these concepts obscure key features of temporary labour migration programs. The argument is developed by examining points of contrast between current programs in place in the USA, Canada, Australia and the UK. The paper concludes by demonstrating how unmasking the power imbalances of this ideology will lead to new policy directions.  相似文献   
73.
Ample research suggests that delinquency, depressive symptoms, and peer substance use are common risk factors associated with adolescent substance use. However, the factors that may help to buffer the deleterious effects of these risk factors on adolescent substance use, such as hope, have yet to be examined. The current study evaluated hope as a moderator of the associations between these common risk factors and frequency of substance use (alcohol, tobacco, and marijuana) in a sample of Latino high school students (M age ?=?16.14 years, SD?=?1.30; 55 % female). Findings indicated that the influence of delinquency on frequency of tobacco and marijuana use depended on levels of hope, with delinquency only positively associated with frequency of use when levels of hope were low. Additionally, hope moderated the association between depressive symptoms and alcohol use, such that depressive symptoms were only positively associated with frequency of alcohol use when levels of hope were low. Results and their implications for intervention are reviewed.  相似文献   
74.
It is imperative that the university environment be supportive and capable of nurturing optimal learning and performance in students. Using job design and work stress theories, the study assessed relationships between psychosocial work characteristics, well-being and satisfaction, and performance in a random sample survey of Australian university students (N = 176). Methodological improvements were a time lag between survey and performance measures, an objective measure of performance, and LISREL structural equation modeling. Results showed high levels of psychological distress and low levels of satisfaction, both linked to high demands combined with low control. In accord with the happy-productive student hypothesis, satisfaction mediated the impact of the work environment on performance. Reengineering the design of the student work environment may therefore improve performance outcomes (student grades) through enhancing satisfaction.  相似文献   
75.
Using the Deese-Roediger-McDermott-Read-Solso (DRMRS) procedure in which list items are shown that are semantically related to a central theme that is not presented, undergraduates (N?=?61) studied either short or long lists in the form of auditory words alone, pictures alone, or pictures accompanied by auditory words. Correct recall and correct recognition scores were similar in all three conditions. However, false memory (reporting the non-presented central theme) was reduced with pictures alone compared to words alone for the recall task, and for the recognition task with short lists. Confidence was higher for correct recall and correct recognition than for false recall and false recognition, but people who were higher or lower in confidence did not differ on any memory measure. Theoretical and practical implications of these results are discussed.  相似文献   
76.
Volitional action and self-control—feelings of acting according to one’s own intentions and in being control of one’s own actions—are fundamental aspects of human conscious experience. However, it is unknown whether high-level cognitive control mechanisms are affected by socially salient but nonconscious emotional cues. In this study, we manipulated free choice decisions to act or withhold an action by subliminally presenting emotional faces: In a novel version of the Go/NoGo paradigm, participants made speeded button-press responses to Go targets, withheld responses to NoGo targets, and made spontaneous, free choices to execute or withhold the response for Choice targets. Before each target, we presented emotional faces, backwards masked to render them nonconscious. In Intentional trials, subliminal angry faces made participants more likely to voluntarily withhold the action, whereas fearful and happy faces had no effects. In a second experiment, the faces were made supraliminal, which eliminated the effects of angry faces on volitional choices. A third experiment measured neural correlates of the effects of subliminal angry faces on intentional choice using EEG. After replicating the behavioural results found in Experiment 1, we identified a frontal-midline theta component—associated with cognitive control processes—which is present for volitional decisions, and is modulated by subliminal angry faces. This suggests a mechanism whereby subliminally presented “threat” stimuli affect conscious control processes. In summary, nonconscious perception of angry faces increases choices to inhibit, and subliminal influences on volitional action are deep seated and ecologically embedded.  相似文献   
77.
Humans detect faces efficiently from a young age. Face detection is critical for infants to identify and learn from relevant social stimuli in their environments. Faces with eye contact are an especially salient stimulus, and attention to the eyes in infancy is linked to the emergence of later sociality. Despite the importance of both of these early social skills—attending to faces and attending to the eyes—surprisingly little is known about how they interact. We used eye tracking to explore whether eye contact influences infants' face detection. Longitudinally, we examined 2‐, 4‐, and 6‐month‐olds' (N = 65) visual scanning of complex image arrays with human and animal faces varying in eye contact and head orientation. Across all ages, infants displayed superior detection of faces with eye contact; however, this effect varied as a function of species and head orientation. Infants were more attentive to human than animal faces and were more sensitive to eye and head orientation for human faces compared to animal faces. Unexpectedly, human faces with both averted heads and eyes received the most attention. This pattern may reflect the early emergence of gaze following—the ability to look where another individual looks—which begins to develop around this age. Infants may be especially interested in averted gaze faces, providing early scaffolding for joint attention. This study represents the first investigation to document infants' attention patterns to faces systematically varying in their attentional states. Together, these findings suggest that infants develop early, specialized functional conspecific face detection.  相似文献   
78.
Research shows that parents have a strong influence on the party preferences of their children. Yet little is known about how such preferences are transmitted in multiparty systems with weak party identification and high electoral volatility. We propose a model of intergenerational transmission that includes both direct effects of parents' party preferences on those of their children, as well as indirect effects through left–right and issue positions. We test this model with original survey data of Dutch adolescents (14–20 years old) and their parents (N = 751 adolescent-parent pairs). We find two paths through which parents exert influence on the party preferences of their adolescent children. On the first path, parental party preferences function as a direct predictor of adolescent party preferences. On the second path, adolescent left–right and issue positions function as a mediator between parental left–right and issue positions and adolescent party preferences, with the effect of left–right positions being stronger than that of issue positions. The frequency with which adolescents discuss political topics with their parents moderates these effects.  相似文献   
79.
80.
This paper explores patients’ views and experiences of undergoing treatment-focused BRCA1 and BRCA2 genetic testing (TFGT), either offered following triaging to clinical genetics (breast cancer) or as part of a mainstreamed care pathway in oncology (ovarian cancer). Drawing on 26 in-depth interviews with patients with breast or ovarian cancer who had undergone TFGT, this retrospective study examines patients’ views of genetic testing at this point in their care pathway, focusing on issues, such as initial response to the offer of testing, motivations for undergoing testing, and views on care pathways. Patients were amenable to the incorporation of TFGT at an early stage in their cancer care irrespective of (any) prior anticipation of having a genetic test or family history. While patients were glad to have been offered TFGT as part of their care, some questioned the logic of the test’s timing in relation to their cancer treatment. Crucially, patients appeared unable to disentangle the treatment role of TFGT from its preventative function for self and other family members, suggesting that some may undergo TFGT to obtain information for others rather than for self.  相似文献   
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