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161.
Adolescent risk-taking behavior has been associated with age-related changes in striatal activation to incentives. Previous cross-sectional studies have shown both increased and decreased striatal activation to incentives for adolescents compared to adults. The monetary incentive delay (MID) task, designed to assess functional brain activation in anticipation of reward, has been used extensively to examine striatal activation in both adult and adolescent populations. The current study used this task with a longitudinal approach across mid-adolescence and late adolescence/early adulthood. Twenty-two participants (13 male) were studied using the MID task at two time-points, once in mid-adolescence (mean age = 16.11; SD = 1.44) and a second time in late adolescence/early adulthood (mean age = 20.14; SD = .67). Results revealed greater striatal activation with increased age in high- compared to low-incentive contexts (incentive magnitude), for gain as well as for loss trials (incentive valence). Results extend cross-sectional findings and show reduced striatal engagement in adolescence compared to adulthood during preparation for action in an incentive context.  相似文献   
162.
163.
根据血压昼夜节律,观察给药时间对血压晨峰的影响。256例原发性高血压患者,经24h动态血压监测分为超杓型(n=49)、杓型(n=127)和非杓型(n=80)3组;各组再分为清晨服药组和晚上服药组。用药6周,比较用药前后血压昼夜节律及血压晨峰的变化,发现在改变血压昼夜节律及降低血压晨峰方面,超杓型组清晨服药优于晚上服药,非杓型组晚上服药优于清晨服药;杓型组清晨服药与晚上服药均能降低晨峰值,提示根据个体血压昼夜节律选择服药时间能更好地控制血压晨峰。  相似文献   
164.
研究胰岛素样生长因子结合蛋白2(IGFBP-2)及胰岛素样生长因子结合蛋白6(IGFBP-6)在结直肠癌中的表达及临床意义。采用免疫组织化学法及RT-PCR方法检测结直肠癌、结直肠腺瘤及癌旁正常黏膜组织中IGFBP-2及IGFBP-6的蛋白及mRNA的表达情况,结合临床病理资料进行统计学分析。IGFBP-2及IGFBP-6蛋白的阳性表达及mRNA的表达量在三组组织中均存在异常表达情况,且差异有明显的统计学意义(P〈0.05),在结直肠癌组IGFBP-2、IGFBP-6的阳性表达在肿瘤浸润深度、有无淋巴结转移及Duke's分期存在差异,有明显的统计学差异(P〈0.05)。临床可以把二者作为结直肠癌诊断及预后的早期预测指标。  相似文献   
165.
This article presents a reanalysis of the data of 862 second and fourth graders collected in two previous studies, focusing on the influence of method (psychometric vs. chronometric) and stimulus type on the gender difference in mental-rotation accuracy. The children had to solve mental-rotation tasks with animal pictures, letters, or cube figures, either in a chronometric condition (computerized) or in a psychometric condition (paper-and-pencil). Results show a slight male advantage in mental-rotation accuracy, which is neither influenced by method nor by stimulus type. However, mental-rotation accuracy differed between the stimulus types, with the highest accuracy in animal pictures and the lowest accuracy in cube figures, and between age groups, with better performance in fourth graders than in second graders in both conditions. Results show that psychometric and chronometric mental-rotation tests with all the stimulus types are more or less similarly usable with children of that age.  相似文献   
166.

Introduction and objective

An experiment was conducted in a school context to examine whether joy and pride, two positive emotions, can promote children's acquisition of knowledge in a reading comprehension situation.

Method

The experiment consisted of inducing either a positive emotion (i.e., joy, pride) or a neutral state to 10-year-old children using an autobiographical recall task. Once the induced state was evaluated, children were submitted to a reading/comprehension task of a neutral text. When they finished reading this text, a questionnaire was used to assess not only their memory of the information provided in the text, but also their ability to make inferences.

Results

Our main results highlighted a positive effect of joy on children's inference making.

Conclusion

This study confirmed the relevance of taking into account the emotional state of children engaged in knowledge acquisition situations at school.  相似文献   
167.
Are face recognition difficulties in Autism Spectrum Disorders (ASD) related to impaired holistic processing? Gauthier et al. [Gauthier, I., Klaiman, C., &; Schultz, R. T. (2009). Face composite effects reveal abnormal face processing in Autism spectrum disorders. Vision Research, 49, 470–478. doi:10.1016/j.visres.2008.12.007] used the face composite task in adolescents with autism and found a congruency effect that was not modulated by alignment, a result which was interpreted as reflecting qualitatively different face processing mechanisms. In the present study we tested adults with ASD in a composite face task where presentation times were manipulated and further explored whether these participants were sensitive to holistic information in faces using a new version of the composite task: VHFPT 2.0 (The Vanderbilt Holistic Face Processing Test 2.0). Results suggest that adults with ASD process faces holistically and that their facial identity processing abilities are qualitatively similar and as efficient as that of typical adults. The difference between the results of Gauthier et al. (2009) with adolescents and the results with adults here reported are interpreted in terms of a developmental delay.  相似文献   
168.
In industrial countries home care services for elderly people living in the community are growing rapidly. Home care nursing is intensive and the nurses often suffer from musculoskeletal pain. Time pressure and job control are job-related factors linked to the risk of experiencing lower back pain (LBP) and LBP-related work impairment. This survey investigated whether work-family conflict (WFC), emotional dissonance and being appreciated at work have incremental predictive value. Responses were obtained from 125 home care nurses (63% response rate). Multiple linear regression showed that emotional dissonance and being appreciated at work predicted LBP intensity and LBP-related disability independently of time pressure and job control. WFC was not a predictor of LBP-related disability in multiple regression analyses despite a zero-order correlation with it. Redesigning the working pattern of home care nurses to reduce the emotional demands and improve appreciation of their work might reduce the incidence of LBP in this group.  相似文献   
169.
This study aims to examine pedestrians' crossing decision, body parts' movement and full body movement, just before and during road crossing in a simulated setup. To accomplish this, a novel experimental setup for analyzing pedestrians’ crossing behavior and motion was developed where the simulated display was synchronized with a 3D motion capturing system. Twenty participants, divided into control and an experimental time pressure group, observed sixteen short (less than 30 s) and long road (70 s or more) crossing scenarios with varying crossing opportunities. Based on the crossing opportunities they were asked to cross a 3.6 m wide one-lane one way urban road. It was found that the crossing initiation process consists of four incremental movements of body parts: the head and the shoulder first; the hip, wrist and elbow second; the knee as a separate joint, and finally the ankle. Results showed that pedestrians’ decision to cross and body parts movement are influenced by time pressure and wait time for a safe crossing opportunity. Specifically, pedestrians prepare their body parts earlier, initiate their crossing earlier, and adjust their speed to compensate for the risk taken in less safe or non-safe crossing opportunities. Within the control group, women tended to be more risk avoiding than men, however those differences disappeared in the time pressure group. Most importantly, the findings provide initial evidence that this novel simulation configuration can be used to gain precise knowledge of pedestrians’ decision-making and movement processes.  相似文献   
170.
Drivers engage in a host of driving-unrelated tasks while on the road. They listen to music, sing-along, and accompany songs by pounding-out drum-kicks and syncopated rhythms on the steering wheel. However, there is controversy over in-cabin music: Does background music facilitate driver performance via increased arousal leading to more focused concentration, or cause distraction placing drivers at greater risk. In an effort to shed light on the debate, the current study evaluated music engagement by employing Music Performance Analyses with audio recordings from three simulated driving conditions. The results indicate that as the perceptual demands of the primary driving task increased, the secondary music activity was hampered, and subsequently sub-optimal vocal and percussive performances were demonstrated consisting of intonation errors, rhythmic inaccuracy, lack of synchrony, inconsistent and unstable temporal flow, neglect of text, and lyric replacement. The findings seem to point out that drivers allocate greater reserves to music than previously considered, and as drivers do not withdraw altogether from music engagement under high-demand driving conditions, driving may be under-resourced. Exploring active music engagement while driving might assist traffic safety researchers in decoding the effects of In-Car Music on driver behavior.  相似文献   
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