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101.
Genetically sterile male Norway rats, Rattus norvegicus, were tested in the laboratory to determine both 1) behavioral characteristics, and 2) the ability of sterile males to compete aggressively and sexually with wild Norway rat males. Sterile males were larger in weight, more frequently dominant, won as many fighting encounters, were as aggressive as wild males, and mounted females more frequently. Behavioral activities were similar for both strains when compared under laboratory conditions with no apparent abnormal behavior exhibited by the sterile males. Use of sterile males in biological control programs is discussed.  相似文献   
102.
Although optimism has several benefits, there are potential drawbacks associated with “too much of a good thing”. Within an academic context, a possible determinant of the adaptiveness of optimistic bias is whether students have a sense of control over academic outcomes: optimistically-biased (OB) achievement expectations paired with perceptions of academic control may enhance performance and well-being; optimistic bias in the absence of perceived control may result in disappointment, poor performance, and diminished well-being. The current longitudinal study examined academic control cognitions (ACC) among OB college students (n = 319) versus non-optimistically biased (non-OB) students (n = 321). We also examined the effects of academic optimistic bias on composite measures of college performance (perceived success, final psychology course grades, cumulative GPA, course attrition) and well-being (positive and negative emotions, health behaviors, future optimism) 6 months later; and determined whether ACC accounted for those associations. Significant MANCOVAs showed OB students had greater ACC, better subsequent well-being, and outperformed their non-OB counterparts. These well-being and performance differences remained significant after statistically accounting for initial aptitude and ACC. Overall, academic optimistic bias was accompanied by perceived controllability over scholastic outcomes, yet beyond the effects of ACC, optimistic bias was associated with better year-end performance and well-being. Findings have implications for maximizing the successful transition of first-year college students.  相似文献   
103.
Singapore is an urban, highly industrialized country in South East Asia. By 2030, one-fifth of the population is projected to be composed of citizens aged above 65 years. Research on aging has largely focused on the effects of deteriorating physical ability on daily functioning capabilities (Iwarsson & Isacsson, 1997; Warr, 1995). More recently, the role of self-perceived usefulness, competence and control on well-being in the elderly have been investigated (Heberlein, Licht & Licht, 1999; Ranzjin, Keeves, Luszcz, & Feather, 1998). In other fields, activity and involvement have been identified as effective coping devices (Nair, 1989; Shalit, 1988). The present study compared the conceptual understanding of the esteem and well-being of the elderly on the dimensions of activity, involvement, and control, as viewed by an undergraduate sample (n = 60) and a cross-section of seniors (n = 71). Three separate factor analyses reflected interesting variations in the conceptual frameworks.  相似文献   
104.
元认知的本质与要素   总被引:110,自引:0,他引:110  
汪玲  郭德俊 《心理学报》2000,32(4):458-463
该文就元认知的本质和要素进行了探讨。文章首先对已有的相关观点进行了分析,在此基础上,将元认知的内涵界定为“个体对当前认知活动的认知调节”,并确定了元认知活动的三要素,即元认知技能、元认知知识、元认知体验,论述了每一要素在元认知活动中的作用,并以元认知三要素关系示意图描述了三者之间的关系。  相似文献   
105.
精神医学是临床医学的一个分枝,是高度复杂的一门科学,站在哲学的角度反思,信息系统控制科学方法渗透于精神医学的历史发展过程和临床工作的资料收集、诊断、治疗等各个环节,以及精神医学的科研工作中,还启迪着我国精神卫生事业的发展方向。  相似文献   
106.
Because indirect measures of personality self‐concepts such as the Implicit Association Test (IAT) allow tapping into automatic processes, they can offer advantages over self‐report measures. However, prior investigations have led to mixed results regarding the validity of indirect measures of conscientiousness. We suggest that these results might be due to a failure to consider the different facets of conscientiousness. These facets are of crucial importance because they are associated differentially with other psychobiological constructs and they are also characterized by different mechanisms. Therefore, focusing on facets while developing indirect measures of conscientiousness may improve the validity of such measures. In Study 1, we conducted a psycholexical investigation to develop one IAT for each conscientiousness facet. In Study 2, we examined the convergent and discriminant validities of each facet IAT in relation to self‐report measures, peer‐report measures and self‐report behavioural indicators, and we investigated differential associations of the conscientiousness facets with working memory capacity and self‐control. We employed network analysis as a novel approach to elucidate differential relationships involving personality facets. The results corroborated the convergent and discriminant validity of the conscientiousness facet IATs with self‐reports and showed that the conscientiousness facets were differentially associated with working memory capacity and with self‐control. Copyright © 2015 European Association of Personality Psychology  相似文献   
107.
The authors examined and compared the effect of support-surface perturbations of various magnitudes on lower extremity kinetics of 7 children with cerebral palsy (CP) and 8 typically developing (TD) children. Results showed that the highest velocity tolerated without stepping was slower in children with CP than in either age-matched TD or younger TD children. Multimodal torque profiles were more frequent in children with CP than in TD controls. TD groups temporally and spatially organized torque activation, whereas children with CP activated all joints simultaneously and showed altered torque contribution patterns among joints. Those results suggest that impairments in reactive postural control in children with CP result not only from developmental delay but also from pathology. Evidence for pathology included increased numbers of torque bursts required to regain stability and less efficient temporal and spatial organization of torque activation patterns.  相似文献   
108.
《Brain and cognition》2014,84(3):330-336
Successful interaction with the environment depends on flexible behaviors which require shifting attention, inhibiting primed responses, ignoring distracting information, and withholding motor responses. These abilities, termed executive function (EF), are believed to be mediated by inhibitory processes in the frontal lobes. Superior performance on EF tests (i.e., faster reaction times (RT), and fewer errors) has been shown in bilinguals compared to monolingual speakers. However, findings are inconsistent, and no study has directly linked this bilingual advantage to frontal lobe inhibitory processes. To clarify this uncertainty, we concomitantly tested neural inhibitory processes and behavioral responses on an EF test in bilinguals and monolinguals. Specifically, we compared English monolinguals (N = 15) to Spanish/English bilinguals (N = 13) on event-related brain potentials (ERP) during a non-linguistic, auditory Go/NoGo task, a task linked to non-motor, cognitive inhibition in monolinguals. Participants responded with a button press on trials in which target tone-pairs (Go trials) were presented and withheld their responses on non-target trials (NoGo trials). Results revealed significantly greater inhibition (i.e., greater mean N2 amplitude) in bilinguals compared to monolinguals during NoGo trials even though both groups performed the task equally well (i.e., withheld a motor response). On Go trials where participants pressed a response button, neither ERPs nor RT distinguished the groups. Additionally, scores on a second language proficiency test (i.e., English in our bilingual group) were positively correlated with N2 amplitude. These findings are the first to directly link this bilingual advantage to a neural correlate of inhibition and to reveal that inhibition in bilinguals is moderated by second language proficiency. Results are discussed in the context of plasticity, and we propose that evaluating bilinguals at varying levels of second-language proficiency may serve as a model of human neuroplasticity.  相似文献   
109.
从分析文献资料入手,对环境与健康的关系进行哲学思考。广西扶绥以玉米为主食的人群,因摄入过量黄曲霉素及饮用污染塘水,导致肝癌高发和高死亡率;而减少黄曲霉素摄入量、改饮清洁水,肝癌发生率和死亡率随之降低。因此,环境与健康相互影响,高温高湿环境诱发玉米产生黄曲霉素,污染塘水存在大量腐殖酸,食之饮之严重危害人的健康;健康意识觉醒,主粮由玉米改为水稻,饮用深井水,健康状况得以改善。在尊重环境与健康相互影响客观性基础上,追求客观性与主观性、人文性的统一。  相似文献   
110.
郭磊  郑蝉金  边玉芳 《心理学报》2015,47(1):129-140
本研究借鉴传统计算机化自适应测验的思想, 并结合认知诊断的特点, 在认知诊断框架下提出了4种变长CD-CAT的终止规则, 分别是属性标准误法(SEA)、邻近后验概率之差法(DAPP)、二等分法(HA)以及混合法(HM)。在未控制曝光和采用不同曝光控制条件下, 与HSU法及KL法进行了比较。研究结果表明:(1) 终止条件越严格, 平均测验长度越长, 按测验长度最大值终止的测验百分比越大, 模式判准率越高。(2) 当未加入曝光控制时, 4种新的终止规则均有较好表现, 与HSU法十分接近。随着最大后验概率预设值的增加或e的减小, 模式判准率呈上升趋势, 平均测验长度逐渐增加, 但在题库使用率方面均较差。(3) 当加入项目曝光控制时, 6种变长终止规则下的题库使用率有了极大的提升, 仍能保持较高的模式判准率, 并且不同的曝光控制方法对终止规则的影响是不同的。其中, 相对标准终止规则极易受到曝光控制方法的影响。(4) 综合来看, SEA、HM以及HA法在各项指标上的表现与HSU法基本一致, 其次为KL法和DAPP法。  相似文献   
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