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971.
This article on mentoring describes demographic characteristics and challenges faced by early career psychologists (ECPs) and how mentoring can significantly shape the development of ECPs’ professional and personal identity. ECPs have a significant impact on how psychology will evolve and be recognized in the marketplace. Mentors have the opportunity to significantly shape the development of this early career professional and thus assure the dynamic future of psychology. The characteristics of a mentor, the mentoring process of an ECP, diversity issues, and strategies for effective mentoring are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
972.
Efficient discrimination between individuals of closely related species is important to maximize reproductive potential. Some studies using males as subjects have indicated that the medial amygdala (MeA) is involved in discrimination between odors of conspecific females and females from distantly related species. The authors investigated the involvement of the MeA in discrimination by females between odors of conspecific males and odors of males of a closely related species. The authors exposed estrous or diestrous female hamsters (Mesocricetus auratus) to saline, conspecific male odors, or heterospecific (M. brandti) male odors and quantified the expression of c-fos–related antigens in the anterior and posterior MeA. They found that estrous (but not diestrous) females investigated conspecific male odors longer than heterospecific male odors. Neural activity in both the anterior and the posterior MeA was higher in estrous than in diestrous females. In the anterior MeA, there were no significant differences in response to odors of conspecific and heterospecific males. In the posterior MeA, however, neural activity was higher when estrous females were exposed to conspecific odors than when they were exposed to heterospecific odors. No such difference was observed in diestrous females. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
973.
Children with unilateral pre- or perinatal brain injury (BI) show remarkable plasticity for language learning. Previous work highlights the important role that lesion characteristics play in explaining individual variation in plasticity in the language development of children with BI. The current study examines whether the linguistic input that children with BI receive from their caregivers also contributes to this early plasticity, and whether linguistic input plays a similar role in children with BI as it does in typically developing (TD) children. Growth in vocabulary and syntactic production is modeled for 80 children (53 TD, 27 BI) between 14 and 46 months. Findings indicate that caregiver input is an equally potent predictor of vocabulary growth in children with BI and in TD children. In contrast, input is a more potent predictor of syntactic growth for children with BI than for TD children. Controlling for input, lesion characteristics (lesion size, type, seizure history) also affect the language trajectories of children with BI. Thus, findings illustrate how both variability in the environment (linguistic input) and variability in the organism (lesion characteristics) work together to contribute to plasticity in language learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
974.
Children’s number competencies over 6 time points, from the beginning of kindergarten to the middle of 1st grade, were examined in relation to their mathematics achievement over 5 later time points, from the end of 1st grade to the end of 3rd grade. The relation between early number competence and mathematics achievement was strong and significant throughout the study period. A sequential process growth curve model showed that kindergarten number competence predicted rate of growth in mathematics achievement between 1st and 3rd grades as well as achievement level through 3rd grade. Further, rate of growth in early number competence predicted mathematics performance level in 3rd grade. Although low-income children performed more poorly than their middle-income counterparts in mathematics achievement and progressed at a slower rate, their performance and growth were mediated through relatively weak kindergarten number competence. Similarly, the better performance and faster growth of children who entered kindergarten at an older age were explained by kindergarten number competence. The findings show the importance of early number competence for setting children’s learning trajectories in elementary school mathematics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
975.
The purpose of the current study was to explore how mother’s and father’s connectedness and involvement individually and collectively influence the lives of their children. Specifically, we asked how fathers’ and mothers’ parent–child connectedness and behavioral involvement influenced both problem behaviors (externalizing and internalizing behaviors) and positive outcomes (prosocial behaviors and hope) during early adolescence. Data for this study were taken from the Flourishing Families Project, from which 349 mothers and fathers were selected, along with their early adolescent child (mean age = 11.23 years, SD = .96). Hierarchical regression analyses revealed (even after controlling for child age, gender, and self-regulation) that mothers’ and fathers’ contributions differed, primarily as a function of child outcome. Namely, father (but not mother) connectedness and involvement were negatively related to adolescents’ internalizing and externalizing behaviors, whereas mother (but not father) connectedness and involvement were positively related to adolescents’ prosocial behaviors and hope. We also found that when one parent’s involvement was low (for whatever reason), the other parent’s involvement made a significant and important contribution to the child’s well-being, particularly in the area of internalizing behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
976.
管品武  陈萌  刘立新  李险峰 《混凝土》2005,(2):66-67,76
利用自行研制的试验装置进行了早龄期商品混凝土的轴向拉伸试验,成功地解决了混凝土试验对中困难的难题。分别得出了轴心抗拉强度和受拉弹性模量随龄期的发展变化规律,并在试验数据的基础上经过回归分析分别得出了轴心抗拉强度和受拉弹性模量随龄期增长的经验公式,为进一步防止和控制混凝土结构的早期裂缝提供了准确可靠的力学性能参数。  相似文献   
977.
数值积分自动终止的算法及其工程应用   总被引:10,自引:5,他引:5  
基于扩展等面积准则(EEAC)稳定性定量分析理论,提出了数值积分的自动终止算法,既大大减少了计算量,又保证不会因为积分时段太短而将多摆失稳的算例判为稳定。该算法根据主导互补簇的簇内非同调程度来反映轨迹在观察时段以后失稳的可能性:当稳定裕度足够大,且互补簇簇内的非同调性足够小时,受扰轨迹在观察时段以后也不会发散。为此,定义了簇内非同调性指标,并开发了识别可疑动态鞍点及可疑最远点的方法。仿真及近3年的大量工程实践证实了该算法的可靠性和有效性。  相似文献   
978.
企业财务风险预警系统研究   总被引:7,自引:0,他引:7  
本文论述了企业财务风险的识别和分析 ,设计了适应我国企业具体特点的财务风险预警系统的结构与子系统、模型 ,提出了建立企业财务风险预警系统的相关对策  相似文献   
979.
文章描述了一种适用于区分服务网络的新的RED改进算法协作可调整RED算法(CARED)。算法的思想是基于令牌桶标记器的标记概率建立业务实际速率与承诺速率间的定量关系,并以这个关系动态调整下游节点中CARED的丢包概率。为了实现CARED,文章还提出了一种标记概率的计算方法基于包数的滑动窗口测量算法(NSWM)。文中通过详实的仿真实验证明了定量关系的正确性,同时验证了CARED算法不仅为区分服务提供了有效的拥塞控制功能,也保障了区分服务的不同性能要求。  相似文献   
980.
低渗透油田启动压力梯度研究   总被引:25,自引:3,他引:22  
胜利油区五号桩油田桩74块为低渗透油田。根据该油田启动压力梯度的测量结果。结合现场生产数据,初步分析了低渗透油田启运压力梯度的趋势及其对注水开发的影响,提出低渗透油田的开发应以早期注水为宜。  相似文献   
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