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971.
The purpose of this study is threefold: first, to describe the characteristics of child abuse and neglect on a major Indian reservation; second, to examine the impact of a community team approach to child abuse and neglect as measured by the incidence of reported abuse and neglect and admissions for emergency foster care; and third, to make recommendations for actions to close the gaps in child welfare services to Indian children living on reservations.  相似文献   
972.
Very few studies have examined issues of work-life balance among faculty of different racial/ethnic backgrounds. Utilizing data from Harvard University’s Collaborative on Academic Careers in Higher Education project, this study examined predictors of work-life balance for 2953 faculty members from 69 institutions. The final sample consisted of 1059 (36%) Asian American faculty, 512 (17%) African American faculty, 359 (12%) Latina/o faculty, and 1023 (35%) White/Caucasian faculty. There were 1184 (40%) women faculty and 1769 (60%) men faculty. The predictors of worklife balance included faculty characteristics, departmental/institutional characteristics and support, and faculty satisfaction with work. While African American women faculty reported less work-life balance than African American men, the reverse was true for Latina/o faculty. In addition, White faculty who were single with no children were significantly less likely to report having work-life balance than their married counterparts with children. Faculty rank was a significant positive predictor of work-life balance for all faculty. Notably, the findings highlight the importance of department and institutional support for making personal/family obligations and an academic career compatible. Institutional support for making personal/family obligations and an academic career compatible was consistently the strongest positive predictor of perceived work-life balance for all faculty. In addition, satisfaction with time spent on research had positive associations with work-life balance for all faculty, highlighting how faculty from all racial/ethnic backgrounds value being able to spend enough time on their own research.  相似文献   
973.
Researchers have long debated the meaning of mathematical understanding and ways to achieve mathematical understanding. This study investigated experienced Chinese mathematics teachers’ views about mathematical understanding. It was found that these mathematics teachers embrace the view that understanding is a web of connections, which is a result of continuous connection making. However, in contrast to the popular view which separates understanding into conceptual and procedural, Chinese teachers prefer to view understanding in terms of concepts and procedures. They place more stress on the process of concept development, which is viewed as a source of students’ failures in transfer. To achieve mathematical understanding, the Chinese teachers emphasize strategies such as reinventing a concept, verbalizing a concept, and using examples and comparisons for analogical reasoning. These findings draw on the perspective of classroom practitioners to inform the long-debated issue of the meaning of mathematical understanding and ways to achieve mathematical understanding.  相似文献   
974.
Relations between self-reported parental reactions to children's negative emotions (PNRs) and children's socially appropriate/problem behavior and negative emotionality were examined longitudinally. Evidence was consistent with the conclusion that relations between children's externalizing (but not internalizing) emotion and parental punitive reactions to children's negative emotions are bidirectional. Reports of PNRs generally were correlated with low quality of social functioning. In structural models, mother-reported problem behavior at ages 10-12 was at least marginally predicted from mother-reported problem behavior, children's regulation, and parental punitive or distress reactions. Moreover, parental distress and punitive reactions at ages 6-8 predicted reports of children's regulation at ages 8-10, and regulation predicted parental punitive reactions at ages 10-12. Father reports of problem behavior at ages 10-12 were predicted by earlier problem behavior and parental distress or punitive reactions; some of the relations between regulation and parental reactions were similar to those in the models for mother-reported problem behavior. Parental perceptions of their reactions were substantially correlated over 6 years. Some nonsupportive reactions declined in the early to mid-school years, but all increased into late childhood/early adolescence.  相似文献   
975.
We report an analysis of reading and spelling processes in a case of developmental disability associated with a genetic anomaly (Klinefelter XXXY syndrome). The results are interpreted within the framework of a model of reading and spelling development (Frith, 1985). An almost complete absence of alphabetic functions was noted. Reading appeared to be based on a ‘logographic lexicon’ (Seymour & Elder, 1986), and spelling on a letter sequence generator which was modifiable by access to a limited store of word images.  相似文献   
976.
Data-driven decision making continues to be a growing educational reform initiative across the globe. The effective use of data requires that teachers develop the knowledge and skills to analyze and use data to improve instruction. The purpose of this article is to examine teachers’ capacity for and beliefs about data use. These issues are examined through a review of research in the past decade. We find that teachers’ beliefs about and capacity for data use are often not connected within the literature or in practice, but we argue they are the heart of the connection between data and instructional change. Teachers’ capacity to use data and their beliefs about data use are shaped within their professional communities, in training sessions, and in their interactions with coaches, consultants, and principals. However, efforts to develop teachers’ capacity for data use often fall short of their goals. Correspondingly, teachers have varied beliefs about data use, and some feel they lack the ability to use data to inform instruction. In order to be more successful, capacity building should directly address teachers’ beliefs, and data use must be decoupled from external accountability demands and involve a variety of information on student learning.  相似文献   
977.
This study explores the impact of one-to-one computing on student achievement in Ohio high schools as measured by performance on the Ohio Graduation Test (OGT). The sample included 24 treatment schools that were individually paired with a similar control school. An interrupted time series methodology was deployed to examine OGT data over a period of 5 to 8 years. Overall student performance and content-specific achievement in math, reading, science, social studies, and writing were not significantly affected by the introduction of 1:1 computing. Treatment schools using a netbook device produced the greatest overall change in scores.  相似文献   
978.
Science instructors and textbook authors often use analogies to help their students use information they already understand to develop an understanding of new concepts. This study reports the results of an analysis of the use of analogies in eight biochemistry textbooks, which included textbooks written for one‐semester survey biochemistry courses for non‐majors; two‐semester courses for chemistry or biochemistry majors; and biochemistry courses for medical school students. We present an analysis of how analogies are used and presented in biochemistry textbooks, and we compare the use of analogies in biochemistry textbooks to the use of analogies in other science textbooks. We also compare the use of analogies in biochemistry textbooks with the factors known to promote spontaneous transfer of attributes and relations from analog concept to target concept. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 43: 1040–1060, 2006  相似文献   
979.
Novel high torque bearingless two-sided rotary ultrasonic motor   总被引:3,自引:0,他引:3  
Applications are limited at present because the currently available ultrasonic motors (USMs) do not provide suffi-ciently high torque and power. The conventional travelling-wave USM needs the bearing to support, which required lubricant. To solve the above problem, a bearingless travelling-wave USM is designed. First, a novel structure of the two-sided USM consisting of a two-sided teeth stator and two disk-type rotors is designed. And the excitation principle of the two-sided travelling-wave USM is analyzed. Then, using ANSYS software, we set up the model of the stator to predict the excitation frequency and modal response of the stator. The shape of the vibration mode was obtained. Last, the load characteristics of the USM are measured using ex-perimental method. The maximum stall torque and the no-load speed were obtained. The results showed that the characteristics of the two-sided USM are better than those of the conventional one-sided USM.  相似文献   
980.
McQueen A  Getz JG  Bray JH 《Child development》2003,74(6):1737-1750
This longitudinal study examined how separation and family conflict mediated the effects of two acculturation variables (English language use and generational status) on substance use (alcohol, tobacco, and marijuana use) and deviant behavior outcomes in a Mexican American high school age sample. Structural equation modeling indicated that separation was a significant mediator of the relationship between acculturation and alcohol use, tobacco use, and deviant behavior. Family conflict mediated the effects of acculturation on marijuana use and deviant behavior. Model comparisons across gender groups suggested that generational status was an influential acculturation measure for females but not males. Additionally, English language use maintained a direct effect on marijuana use among females, whereas this relationship was mediated by separation for males.  相似文献   
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