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971.
OBJECTIVE: This study compared recidivism rates for alleged maltreatment perpetrators whose initial report was substantiated and those whose initial report was not substantiated, to determine whether they returned to the child welfare system at differing rates. METHOD: Statewide administrative child welfare services data over a period of 4 1/2 years was analyzed. The sample included 31,531 perpetrators of intrafamilial maltreatment. Separate analyses were conducted for each type of maltreatment (sexual abuse, physical abuse, and neglect). RESULTS: Bivariate relationships (substantiation status and recidivism) were analyzed using survival curves, and the study found that recidivism patterns differed by type of maltreatment and by substantiation status at the index event. Multivariate analyses using Cox Proportional Hazards models found that bivariate relationships held true even when controlling for neighborhood mean income, ethnicity, and gender. CONCLUSIONS: The study's finding that perpetrators whose index event was not substantiated return to the child welfare system at a high rate suggests the need to learn how to discriminate those unsubstantiated alleged perpetrators who are most at risk for recidivism. The finding of frequent cross-type recidivism indicates that intervention should focus on common themes across maltreatment types. 相似文献
972.
David Mahony 《高等教育研究与发展》1994,13(1):71-84
Both Australia and Britain have recently moved from a binary system of higher education to a unitary system based upon the universities. In both countries change has been affected by an increasing emphasis upon higher education as a vital national economic resource and the need to make higher education institutions” more efficient.” As a result universities have a much closer relationship with government than ever before.
Yet there are important differences: Australia ended its binary system by consolidating its Colleges of Advanced Education into the university system. In Britain the trend has been to redesignate polytechnics as universities without amalgamation. Britain has evolved a much more competitive system in the allocation of resources which has had a profound affect upon the universities.
This article explores major similarities and contrasts in the Australian and British experiences. 相似文献
973.
The pressure to reduce solar energy costs encourages efforts to reduce the thickness of silicon wafers. Thus, the cell bowing problem associated with the use of thin wafers has become increasingly important, as it can lead to the cracking of cells and thus to high yield losses. In this paper, a systematic approach for simulating the cell bowing induced by the firing process is presented. This approach consists of three processes: (1) the material properties are determined using a nanoidentation test; (2) the thicknesses of aluminum (Al) paste and silver (Ag) busbars and fingers are measured using scanning electron microscopy; (3) non-linear finite element analysis (FEA) is used for simulating the cell bowing induced by the firing process. As a result, the bowing obtained using FEA simulation agrees better with the experimental data than that using the bowing calculations suggested in literature. In addition, the total in-plane residual stress state in the wafer/cell due to the firing process can be determined using the FEA simulation. A detailed analysis of the firing-induced stress state in single crystalline silicon (sc-Si), cast, and edge-defined film-fed growth (EFG) multi-crystalline silicon wafers of different thicknesses is presented. Based on this analysis, a simple residual stress calculation is developed to estimate the maximum in-plane principal stress in the wafers. It is also proposed that the metallization pattern, Ag busbars and fingers screen printed on the front of a solar cell, can be designed using this approach. A practical case of a 3-busbar Si solar cell is presented. 相似文献
974.
975.
John M. Reveles Gregory J. Kelly Richard P. Durán 《Cultural Studies of Science Education》2007,1(3):467-495
This ethnographic study of a third grade classroom examined elementary school science learning as a sociocultural accomplishment.
The research focused on how a teacher helped his students acquire psychological tools for learning to think and engage in
scientific practices as locally defined. Analyses of classroom discourse examined both how the teacher used mediational strategies
to frame disciplinary knowledge in science as well as how students internalized and appropriated ways of knowing in science.
The study documented and analyzed how students came to appropriate scientific knowledge as their own in an ongoing manner
tied to their identities as student scientists. Implications for sociocultural theory in science education research are discussed.
John Reveles is an assistant professor in the Elementary Education Department at California State University, Northridge. He received
his Ph.D. from the University of California, Santa Barbara in 2005. Before pursuing his Ph.D., he worked as a bilingual elementary
school teacher for 3 years. His research focuses on the development of scientific literacy in elementary school settings;
sociocultural influences on students' academic identity; equity of access issues in science education; qualitative and quantitative
research methods. Within the Michael D. Eisner College of Education, he teaches elementary science curriculum methods courses,
graduate science education seminars, and graduate research courses.
Gregory Kelly is a professor of science education at Penn State University. He is a former Peace Corps Volunteer and physics teacher. He
received his Ph.D. from Cornell in 1994. His research focuses on classroom discourse, epistemology, and science learning.
This work has been supported by grants from Spencer Foundation, National Science Foundation, and the National Academy of Education.
He teaches courses concerning the uses of history, philosophy, sociology of science in science teaching and teaching and learning
science in secondary schools. He is editor of the journal Science Education.
Richard Durán is a Professor in the Gevirtz Graduate School of Education, University of California, Santa Barbara. His research and publications
have been in the areas of literacy and assessment of English Language Learners and Latino students. He has also conducted
research on after school computer clubs, technology and learning as part of the international UC Links Network. With support
from the Kellogg Foundation, he is implementing and investigating community and family-centered intervention programs serving
the educational progress of Latino students in the middle and high school grades. 相似文献
976.
We analyzed how two basic electromagnetism textooks approach the concept of electric field. We limited our study to the reasons given in these textbooks for the introduction of the field representation and to how accurate, coherent, and complete these reasons are. Because many times historical reasons are intertwined with textbooks' explanations of physical phenomena, we used the historical evolution of the field representation to guide our analysis. The analysis shows that one textbook mixes up the historical and pedagogical reasons for the introduction of the concept of field. The other one presents a sketch that might lead students to understand the field and the action-at-a-distance views as supplementing each other. 相似文献
977.
Maria Gouveia-Pereira Jorge Vala Augusto Palmonari Monica Rubini 《European Journal of Psychology of Education - EJPE》2003,18(3):309-325
This study analysis the relationship between perceptions of the justice of teacher’ behaviour and (a) the legitimation of school authority and (b) the legitimation of institutional authorities outside school. 448 adolescent students participated in the study. In questionnaire participants were asked about (a) perceptions of the justice of teachers’ behaviour; (b) evaluation of the school experience; and (c) evaluation of institutional authorities. Results show that the evaluation of the justice of teacher behaviour, in particular relational and procedural justice, have an impact on the legitimation of the authority of teachers and on the evaluation of institutional authorities outside school. Results also show that the legitimacy granted to teachers is a mediator variable between perceptions of justice in school and evaluation of authorities outside school. These results are discussed in the context of the studies on the relationship between school experience and adolescents attitudes towards authorities, and in the framework of the “Relational Model of Authority” and of the “Group Value Model”. 相似文献
978.
Ng Pak Tee 《Educational Research for Policy and Practice》2004,3(3):183-198
Schools in Singapore are now tasked to develop the spirit of innovation and enterprise in their students. This is in line with the national vision of ‘Thinking Schools, Learning Nation’. This policy initiative, which began in 2004, is set to change the fundamental nature of education in Singapore. This article discusses the innovation and enterprise (I&E) initiative, its major implications for schools in Singapore and the areas still to be addressed in the implementation of the policy. In particular, the article discusses the issues of teachers and school leaders as role models of I&E, I&E as an organic part of school business, the influence of the wider societal culture and values system, and the measurement of success of I&E. The challenge for schools is to go beyond the form of the initiative to bring real substantial and sustainable change through this movement. 相似文献
979.
A SYSTEMIC,STUDENT-CENTERED STUDY OF UNIVERSITY SERVICE 总被引:1,自引:0,他引:1
This paper discusses the methods and findings ofthe Student Focus Project, a sixmonth study of studentperceptions of service at a large university inBrisbane, Australia. The study paneled 24 focus groups of undergraduate students to assess theirbeliefs about a pretested set of questions concerningpositive and negative aspects of university life,successes and frustrations with university service,attempts to overcome the obstacles of university life,and what students expect from their relationship to theuniversity. Of the themes identified in the StudentFocus study, it was found that malignantbureaucracy and the balkanization ofInformation are systemic factors that negativelyinfluence student perceptions of the quality ofuniversity service. It was also found that studentstrategies for service recovery can contribute to the overall confusion andpoor performance of university services. 相似文献
980.
Eun-hye Park Won-young Bae Jae-yeon Kim Kee-tae Kim Hyun-dong Paik 《Journal of Zhejiang University. Science. B》2017,18(9):816-824
The inhibitory effects of Lactobacillus plantarum-fermented and non-fermented Inula britannica extracts on the tyrosinase activity were comparatively investigated to examine whether and how they improve the whitening activity, and the contents of total flavonoids and polyphenolics as bioactive compounds were determined. The skin whitening activity using in vitro or ex vivo tyrosinase and L-3,4-dihydroxyphenylalanine (L-DOPA) staining was examined. The total flavonoid content (TFC) was increased by 13.4% after 72 h-fermentation. The viabilities of the B16F10 cells treated with the fermented and non-fermented control extracts were 100.26% and 92.15% at 500 μg/ml, respectively. In addition, the inhibition of tyrosinase activity was increased by the fermented samples from 29.33% to 41.74% following fermentation for up to 72 h. The tyrosinase activity of the untreated control group was increased to 145.69% in B16F10 cells. The results showed that I. britannica fermented by L. plantarum dose-dependently inhibited tyrosinase activity, which was stimulated by α-melanocyte stimulating hormone. These results suggest that lactic fermented I. britannica extracts can be used as effective skin-whitening materials. 相似文献