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91.
Serving low-income children from birth to age five and their families, Head Start is a primary venue for identification and intervention in the area of child mental health. However, recent research has demonstrated that the knowledge base regarding prevalence, developmental course, and predictive power of child mental health problems is lacking for young children in general and low-income, diverse populations in particular. Head Start's agency-level data is often discrepant from both national estimates and small, intensive studies of similar populations, perhaps for reasons related to availability of community services and professional staff, as well as concerns about stigmatization. Following on recent expert recommendations, new collaborative Federal initiatives are underway to increase our understanding of the types, trajectories, and treatments of mental health problems affecting the vulnerable children served by Head Start. The paper concludes with a call to action for the field in the area of young children's mental health.  相似文献   
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The purpose of this study was to determine whether the dynamics and structure of mother-child interactions around toys vary with the familiarity of toys. Twelve mother-child dyads with a 5- or 9-month-old infant were filmed two consecutive 5-minute sessions in the presence of familiar or novel objects. By relating the mother’s behaviour to her infant’s, we were able to define episodes consisting of phases of joint engagement of the two partners on the same topic or reference object. In a context involving familiar objects, mothers more often took the initiative to introduce a topic, and they kept the child’s attention focused on the object for longer periods, by means of various manipulations. In contrast, the attractiveness of the novelty gave the infants more initiative, and the mothers followed the child by providing mostly verbal support.  相似文献   
94.
That the sample mean and variance are “good” estimates of the corresponding population parameters is easily accepted as “obvious” by students, but the concept of standard error of the mean is often found to be quite a hurdle. That this standard error decreases inversely as the square-root of the sample size, and the mysterious appearance of the Normal distribution, are often taken as magical and incomprehensible effects, and non-mathematical students can often be turned away from further understanding. This article describes a program which provides an experimental framework in which the student can rapidly develop an intuition for the basic properties of sampling.  相似文献   
95.
The nexus between college choice and persistence   总被引:2,自引:3,他引:2  
Initial student commitments have long been considered an influence on persistence, but the reasons why students choose to attend a college have seldom been considered as dimensions of initial commitments that could influence persistence processes and outcomes. This study used NPSAS-87 to examine the influence of finance-related reasons for choosing a college on persistence decisions. The findings include (1) finance-related choices have direct and indirect influences on whether students persist in college; and (2) market-based, monetary measures of financial aid, tuition costs, housing costs, and other living costs have a substantial direct effect on persistence.  相似文献   
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Evidence of substantial growth in unionization among university noninstructional staff over the past 20 years (Hurd and Woodhead, 1987) and the emergence of a quality movement in higher education linking employee attitudes toward the work environment with increased productivity point to the need for additional research into union and nonunion staff perceptions of the work environment. This paper describes a conceptually oriented, exploratory study of the university work environment as perceived and defined by union and nonunion noninstructional staff.  相似文献   
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Despite its frequent use, there is little understanding of the concept of differential among upper high school and undergraduate students of physics. As a first step to identify the origin of this situation and to revert it, we have done a historic and epistemological study aimed at clarifying the role and the meaning of the differential in physics and at improving curricular and teaching models in the sense of Gilbert et al. (Gilbert J.K., Boulter C., & Rutherford, M.: 1998a, International Journal of Science Education 20(1), 83–97, Gilbert J.K., Boulter C., & Rutherford, M.: 1998b, International Journal of Science Education 20(2), 187–203). We describe the contributions of Leibniz and Cauchy and stress their shortcomings, which are overcome by the alternative definition proposed by the French mathematician Fréchet, dating from early 20th century. As a result of this study, we answer to some fundamental questions related to a proper understanding of the differential in physics education (for 17–19 years old students).  相似文献   
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