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921.
Animal and human research has shown that pain sensitivity changes during the menstrual cycle. This has sometimes been ascribed to hormonal variations. The aim of the present study was to examine how perception of pain, induced by the cold pressor test to the dominant hand, was related to gender and phases of the menstrual cycle. A repeated-measures design was used, where twenty-two female students participated at two different phases of the menstrual cycle (days 2-4 and days 20-24). A control group of nineteen male students participated on two occasions, separated by a three week period. The cycle phase during which each woman began her participation was randomized. Pain was induced using the cold pressor test. Pain threshold was determined as the duration of time between when the subject first reported pain and exposure to the painful stimulus. Pain tolerance was determined as the duration of time until the subject withdraw her/his hand from the test water because the pain was too intensive. The results showed that men tolerated significantly greater pain than women. Women's pain threshold was significantly higher during the second phase of the menstrual cycle. Systolic pressure was higher in men than women, increasing more in men in response to cold pressor testing than women. Further research, including measurements of plasma hormone levels during the menstrual cycle, is needed to clarify the role played by estrogens in pain perception.  相似文献   
922.
923.
Children with sickle cell anemia (SCA) have elevated cerebral blood velocity relative to healthy peers. The primary aim of this study was to evaluate the association between cerebral blood velocity, measured by transcranial Doppler (TCD) ultrasound, age, and gender with cognitive function in children with SCA in Nigeria. Eighty-three children (Mage = 9.10, SD = 1.90 years; 55% female) with SCA in Nigeria completed cognitive assessments and a TCD ultrasound. The association between TCD velocity and measures of perceptual reasoning (Raven’s Progressive Matrices), working memory (WISC-IV Digit Span), and executive planning (Tower of London, TOL) were assessed. Results showed that elevated TCD velocity significantly predicted lower scores on TOL Time Violations and Total Problem-Solving Time when controlling for BMI, hemoglobin level, and parent education, suggesting that TCD velocity is related to the efficiency of executive function. Further, age was negatively related to children’s performance on the Ravens Matrices and TOL Total Correct, and boys showed greater deficits on the TOL Total Correct relative to girls. Moderation analyses for gender showed that there was a conditional negative association between TCD velocity and Digit Span for boys, but not for girls. Findings suggest that children with SCA in Nigeria with elevated TCD velocity are at risk for deficits in efficiency of executive planning, and boys with elevated TCD velocity are particularly at increased risk for deficits in auditory working memory. Implications of this study are important for interventions to reduce cerebral blood velocity and the use of TCD in this population.  相似文献   
924.
925.
不同社会群体特征对内隐领导因素的影响   总被引:2,自引:0,他引:2  
研究发现,中国人内隐领导理论的内容由个人品德、目标有效性、人际能力和多面性四个因素构成。不同的年龄、职业和教育水平等评分者的特点,对领导诸因素的评分有着显著的影响。综合分析发现,教育水平是影响内隐领导因素评分的主要变量。另外,各组都倾向于把人际能力作为领导最大的特质来加以评分。  相似文献   
926.
In Nigeria, communal conflicts arise due to misunderstanding from ownership of land for farming, oil deposits, solid minerals or water for fishing activities. It may also arise in defence of community pride and properties or even in defence of the people involved in the conflict. The General Health Questionnaire (GHQ-12), The Short Screening Scale for Post traumatic stress disorder, The Generalized Anxiety Disorder Scale (GAD-7) and the Beck Depression Inventory (BDI-2) were used to assess psychosocial impacts of communal conflicts among 560 secondary school youths from two communities in south east Nigeria. Result revealed various forms of psychosocial impacts of communal conflicts among the youths.  相似文献   
927.
So-called “looks-at-nothing” have previously been used to show that recalling what also elicits the recall of where this was. Here, we present evidence from an eye-tracking study which shows that disrupting looks to “there” does not disrupt recalling what was there, nor do (anticipatory) looks to “there” facilitate recalling what was there. Therefore, our results suggest that recalling where does not recall what.  相似文献   
928.
929.
Teachers’ formal accountability and duties have been the focus of high-stakes educational reforms, for instance in the context of national accountability systems. Yet, teachers’ sense of personal (rather than formal) responsibility and willingness to assume responsibility for their teaching and students remains an understudied area. The main purpose of this study was to investigate contextual and person-specific predictors of teachers’ sense of personal responsibility, as well as the potential implications of teachers’ personal responsibility for their instructional approaches and wellbeing. A path analysis indicated that high school teachers (n = 287) who felt responsible for their teaching and students reported higher levels of work engagement and job satisfaction than less responsible teachers, and were more likely to endorse mastery-oriented instructional practices that emphasized student effort, task mastery, and individual growth. Teachers’ perceptions of their school’s social climate (teachers’ evaluations of their relationships with students), their sense of teaching self-efficacy, and incremental beliefs of intelligence emerged as positive predictors of teacher responsibility. Teacher responsibility partially mediated the positive effects of these predictors on teachers’ wellbeing and mastery-oriented instructional practices. The results suggest that both contextual (e.g., school climate) and person-specific (e.g., self-efficacy) factors can contribute to teachers’ sense of personal responsibility, and that responsibility, in turn, can have positive implications for teachers’ wellbeing and instructional practices. Directions for future research and practical implications are considered.  相似文献   
930.
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