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751.
Two studies investigated relations between supervisors' evaluations of contextual performance and personality characteristics in jobs where opportunities for advance- ment were either absent or present. The first study examined performance in entry- level jobs where advancement, in general, was precluded; employees (N = 214) completed the Hogan Personality Inventory (HPI) as applicants and subsequently were rated by their supervisors for contextual performance. Results indicated that conscientiousness-measured by HPI Prudence scores-was significantly related to ratings of Work Dedication and Interpersonal Facilitation, which are dimensions of contextual performance. The results were corroborated in an independent sample. In the second study, employees (N = 288) in jobs with opportunities for advancement completed the HPI and their supervisors provided ratings for contextual performance. Results indicated that ambitiodsurgency-measured by HPI Ambition scores-pre- dicted contextual performance. These results also were confirmed in a second sample. Relations between personality and contextual performance are explained by the motives of cooperation-getting along-and status-getting ahead.  相似文献   
752.
Background: The most common route for general population exposure to methyl mercury (MeHg) is fish consumption. Recommendations to pregnant women about consuming fish contaminated with MeHg are also applied to children, but there are few studies available about the effects of low-level postnatal MeHg exposure in them.

Objectives: To investigate the association between postnatal methyl mercury exposure and neuropsychological development in a study of children also exposed to lead, both measured at 7 years.

Methods: We measured MeHg concentrations in blood samples from the Treatment of Lead-Exposed Children (TLC) trial in which 780 children with elevated concentrations of lead in blood were followed with neuropsychological tests from ages 12–33 months through 7 years. Here we examine blood MeHg concentration and neuropsychological test scores, both measured at age 7 years. We used a maximum likelihood method to estimate geometric mean MeHg concentration and generalized linear regression models to analyze MeHg and neuropsychological test scores.

Results: Geometric mean MeHg concentration was 0.56 (95% confidence interval: 0.52, 0.59) μg/L. A 1 μg/L increase in MeHg was associated with a 2.1 (95% confidence interval: 0.4, 3.8) point increase in Full-Scale IQ and 0.2 (95% confidence interval: 0.02, 0.4) point increase in Learning Slopeindex T-score on a test of verbal memory.

Conclusions: Our results suggest that the relatively low MeHg exposure in US school-aged children from this population has no detectable adverse effect on neuropsychological development. The positive associations observed between MeHg and neurodevelopment may indirectly reflect consumption of beneficial polyunsaturated fatty acids from seafood.  相似文献   
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755.
Performance decrements attributed to mental fatigue have been found to be especially pronounced in tasks that involve the voluntary control of attention. Here we explored whether mental fatigue from prolonged time on task (TOT) also impairs temporal preparation for speeded action in a simple reaction-time task. Temporal preparation is enabled by a warning signal presented before the imperative stimulus and usually results in shorter reaction time (RT). When the delay between warning and imperative stimuli - the foreperiod (FP) - varies between trials, responses are faster with longer FPs. This pattern has been proposed to arise from either voluntary attentional processes (temporal orienting) or automatic trial-to-trial learning (trace conditioning). The former account suggests a selective RT increase on long-FP trials with fatigue; the latter account suggests no such change. Over a work period of 51 min, we found the typical increase in overall RT but no selective RT increase after long FPs. This additivity indicates that TOT-induced mental fatigue generally reduces cognitive efficiency but leaves temporal preparation under time uncertainty unaffected. We consider this result more consistent with the trace-conditioning account of temporal preparation.  相似文献   
756.

Objective

Extremely low body mass index (BMI) values are associated with increased risk for death and poor long-term prognosis in individuals with anorexia nervosa (AN). The present study explores childhood personality characteristics that could be associated with the ability to attain an extremely low BMI.

Methods

Participants were 326 women from the Genetics of Anorexia Nervosa (GAN) Study who completed the Structured Interview for Anorexia Nervosa and Bulimic Syndromes and whose mother completed the Child Behavioral Checklist and/or Revised Dimensions of Temperament Survey.

Results

Children who were described as having greater fear or anxiety by their mothers attained lower BMIs during AN (p < 0.02). Path analysis in the GAN and a validation sample, Price Foundation Anorexia Nervosa Trios Study, confirmed the relation between early childhood anxiety, caloric restriction, qualitative food item restriction, excessive exercise, and low BMI. Path analysis also confirmed a relation between childhood anxiety and caloric restriction, which mediated the relation between childhood anxiety and low BMI in the GAN sample only.

Conclusion

Fearful or anxious behavior as a child was associated with the attainment of low BMI in AN and childhood anxiety was associated with caloric restriction. Measures of anxiety and factors associated with anxiety-proneness in childhood may index children at risk for restrictive behaviors and extremely low BMIs in AN.  相似文献   
757.
Despite the rhetoric of a single global economy, professionals in poorer countries continue to be remunerated differently depending on whether they are compensated at a local vs. international rate. Project ADDUP (Are Development Discrepancies Undermining Performance?) surveyed 1290 expatriate and local professionals (response rate = 47%) from aid, education, government, and business sectors in (1) Island Nations (Papua New Guinea, Solomon Islands), (2) landlocked economies (Mala?i, Uganda), and (3) emerging economies (India, China). Difference in pay was estimated using purchasing power parity, from the World Bank's World Development Indicators 2007. Psychological measures included self‐reported pay and benefits (remuneration), self‐attributed ability, remuneration comparison, sense of justice in remuneration, remuneration‐related motivation, thoughts of turnover and thoughts about international mobility. We included control measures of candour, culture shock, cultural values (horizontal/vertical individualism/collectivism), personality (from the “big five”), job satisfaction and work engagement. Controlling for these and country (small effects) and organization effects (medium), (a) pay ratios between international and local workers exceeded what were perceived to be acceptable pay thresholds among respondents remunerated locally; who also reported a combination of a sense of relative (b) injustice and demotivation; which (c) together with job satisfaction/work engagement predicted turnover and international mobility. These findings question the wisdom of dual salary systems in general, expose and challenge a major contradiction between contemporary development policy and practice, and have a range of practical, organizational, and theoretical implications for poverty reduction work.  相似文献   
758.
Three children with autism were taught abduction‐prevention skills using behavioral skills training with in situ feedback. All children acquired the skills, which were maintained at a 1‐month follow‐up assessment. In addition, 1 of the children demonstrated the skills during a stimulus generalization probe in a community setting.  相似文献   
759.
Sven Walter 《Synthese》2010,177(2):285-300
During the past decade, the so-called “hypothesis of cognitive extension,” according to which the material vehicles of some cognitive processes are spatially distributed over the brain and the extracranial parts of the body and the world, has received lots of attention, both favourable and unfavourable. The debate has largely focussed on three related issues: (1) the role of parity considerations, (2) the role of functionalism, and (3) the importance of a mark of the cognitive. This paper critically assesses these issues and their interconnections. Section 1 provides a brief introduction. Section 2 argues that some of the most prominent objections against the appeal to parity considerations fail. Section 3 shows that such considerations are nevertheless unsuitable as an argument for cognitive extension. First, the actual argumentative burden is carried by an underlying commitment to functionalism, not by the parity considerations themselves. Second, in the absence of an independently motivated mark of the cognitive, the argument based on parity considerations does not get off the ground, but given such a mark, it is superfluous. Section 4 argues that a similar dilemma arises for the attempt to defend cognitive extension by a general appeal to functionalism. Unless it can be independently settled what it is for a process to be cognitive, functionalism itself will be undermined by the possibility of cognitive extension. Like parity considerations, functionalism is thus either unable to support cognitive extension or superfluous. Hence, nothing short of the specification of an appropriate mark of the cognitive that can be fulfilled not only by intracranial but also by extended processes will do as an argument for cognitive extension.  相似文献   
760.
The treatment components that contribute to and account for successful therapeutic outcomes for people who stutter are not well understood and are debated by many. The purpose of this phenomenological study was to describe in detail the underlying factors that contribute to a successful or unsuccessful therapeutic interaction between clients and their clinicians. Twenty-eight participants, 19 men and 9 women, who had received from 6 months to more than 12 years of therapy for stuttering were studied. The participants were asked to consider their experience with one or more speech-language pathologists with whom they had received fluency therapy and to describe the characteristics that made that individual effective or ineffective in promoting successful change in their ability to communicate. Analysis of these data resulted in 15 primary categories. Finally, the essential structure of an effective and ineffective therapeutic interaction was described. Results highlighted the importance for effective therapy of understanding the stuttering experience, forming a positive client-clinician, alliance, and being knowledgeable about stuttering and its treatment. Educational objectives: The reader will be able to: (1) describe, from the perspective of a select group of adults who stutter, the themes associated with an effective therapeutic interaction, (2) describe, from the perspective of a select group of adults who stutter, the themes associated with an ineffective therapeutic interaction, and (3) describe the ways in which an effective or ineffective therapeutic interaction could impact a person who stutters.  相似文献   
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