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1.
This paper summarizes three lines of research that are motivated by the practical problem of helping users find information from external data sources, most notably computers. The application areas include information retrieval, text categorization, and question answering. A common theme in these applications is that practical information access problems can be solved by analyzing the statistical properties of words in large volumes of real world texts. The same statistical properties constrain human performance, thus we believe that solutions to practical information access problems can shed light on human knowledge representation and reasoning.  相似文献   
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Our aim was to explore the role of parents in the transmission of stereotypical body size attitudes and awareness of weight loss strategies to preschool children. Participants were 279 3‐year‐old children and their parents, who provided data at baseline and 1 year later. Parents completed self‐report body size attitude and dieting measures. Child weight bias and awareness of weight loss strategies were assessed through interview. Over time, negative associations with large bodies and awareness of weight loss strategies increased. Fathers’ attitudes prospectively predicted boys’ weight bias and awareness of weight loss strategies. Among girls, parental attitudes were less predictive. Findings confirm the importance of fathers in the development of boys’ body attitudes and inform prevention programmes.  相似文献   
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The ability of two species of tits to remember the location and/or features of an object was tested in a delayed-matching-to-sample procedure. Three values of retention interval between presentation of the sample stimulus and the choice--30 sec, 5 min, and 15 min--were used. Both species performed at above-chance level at all retention intervals, and there was no significant decline in accuracy with increasing interval. A pool of 100 stimulus objects was used, but the results of control trials indicated that the birds responded primarily to location rather than stimulus features of the object itseif. Although the food-storing marsh tit tended to perform at a higher level than the non-storing great tit, the only significant difference between the species was in the first 50 trials of the first treatment, when the birds were acquiring the task. The results are discussed in relation to the hypothesized special memory capacity of food-storing birds.  相似文献   
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OBJECTIVE: To examine dysregulation in biological measures associated with histories of abuse in women and whether women with premenstrual dysphoric disorder (PMDD) differ in their dysregulation. DESIGN: Twenty-five women meeting prospective criteria for PMDD and 42 non-PMDD controls underwent structured interview to determine abuse histories and lifetime Axis I diagnoses, excluding those with current Axis I disorders or using medications. MAJOR OUTCOME MEASURES: Plasma cortisol and norepinephrine (NE), heart rate (HR), blood pressure (BP), and vascular resistance index (VRI) were assessed at rest and in response to mental stress. RESULTS: A greater proportion of PMDD women had prior abuse compared with non-PMDD women. Regardless of PMDD status, all abused women had lower plasma NE and higher HRs and tended to have lower plasma cortisol at rest and during stress. Abused women also reported more severe daily emotional and physical symptoms. Greater VRI and BP at rest and during stress were seen only in PMDD women with abuse. CONCLUSION: There is persistent dysregulation in stress-responsive systems in all abused women that cannot be accounted for by current psychiatric illness or medications, and PMDD women may be differentially more vulnerable to the impact of abuse on measures reflecting alpha-adrenergic receptor function.  相似文献   
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Abstract

This study builds on and extends previous sales leadership research by exploring sales professionals’ perceptions of effective leadership behaviors. Semistructured interviews with both sales leaders and salespeople working in a global enterprise software company were examined through a qualitative analysis. Results indicated that participants believed sales leadership played an important role in influencing sales performance. When asked to describe specific sales leader behaviors that best enable salesperson performance, sales professionals – both sales leaders and salespeople – overwhelmingly referenced coaching, followed by collaborating, championing, and customer engaging. We define and describe these four key sales leader behaviors and identify four potential mediating variables (trust, confidence, optimism, and resilience), from which emerges a conceptual framework of sales leader behaviors perceived to enable salesperson performance. We examine these four key sales leader behaviors and mediators in the broader context of leadership theory, particularly transformational, servant, authentic, and adaptive leadership theories. The key contribution of this study is the identification of a set of leader behaviors that are likely to be especially effective in modern sales organizations given that they originated from the perceptions of sales professionals themselves.  相似文献   
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The child-rearing beliefs of 32 mothers and 36 day-care providers in Mexico were compared. Day-care providers expected children to master developmental skills at an earlier age than did mothers. Day-care providers more strongly valued the development of independent and cooperative behavior, and placed less importance on obedience. They also reported employing more flexible and nonauthoritarian discipline strategies than did mothers. Mothers and caregivers did not differ in the extent to which they attributed the success of their discipline strategies to their own actions rather than to external factors. Also examined was how mothers' beliefs differed in families characterized by interdependent versus individualistic social structures. In interdependent families, mothers were more likely to believe in later mastery of developmental skills and to make external attributions. These findings suggest that Mexican children experience incongruous social norms as they move between home and day care settings, and that these norms, at least within the home, are associated with the social structural features of the setting.  相似文献   
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Converging evidence for multiple genetic forms of reading disability   总被引:3,自引:0,他引:3  
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