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121.
Worldwide there has been a range of initiatives in the area of standards for teachers as part of a discourse of professionalism. In Australia there are a plethora of standards: state and territory frameworks, generic and subject‐specific, systemic and cross‐systemic, for pre‐service, beginning and experienced teachers. Little has been written as to how teacher education programs are responding to the standards agenda. This paper positions standards as integral to the recontextualizing field (Bernstein, 2000) for teacher educators and their programs. Using Bernsteinian concepts of fields, identities and framing, we compare the responses of two physical education teacher education programs to their state's standards imperatives. The authors conclude that the academic orientation of the university, together with the framing of the standards, affect the degree of programmatic change it will undertake in response to the changes in teacher certification standards. 相似文献
122.
Three experiments examined “atomistic” and “configurai” processes in stimulus compounding using the rabbit’s conditioned nictitating membrane response. Two conditioned stimuli (CSs) were trained separately and then tested together in a compound. Animals trained with CSs from different modalities—namely, tone and light—showed summation in both acquisition and extinction. That is, the probability of a response to the compound could be predicted by the statistical sum of responding to the CSs. In contrast, animals trained with CSs from the auditory modality, tone and noise, showed a level of responding to the tone + noise compound that was the same as that of the CSs, well under the level predicted by the statistical sum of responding to the CSs. In conclusion, atomistic processes appear to predominate in cross-modal compounding. Configurai processes may occur during compounding within the auditory modality, but atomistic alternatives—namely, common elements and selective attention hypotheses—may be able to explain the results. 相似文献
123.
Severe underrepresentation of African-Americansamong postsecondary faculty is often linked toeducational pipeline supply problems,while institutional variations in demandfor black faculty labor and barriers to theirrecruitment and retention receive less empiricalattention. Using a nationally representative sample ofcollege faculty from a wide array of institutions andscience disciplines, this study investigates linksbetween internal organizational conditions and blackfaculty representation. Hypotheses derive from competingexplanations of the role of race in academicorganizations: institutionalized discrimination to protectdominant group privileges; statistical discriminationbased on expectations of racial group differences inacademic preparation; labor supply and politicalconstraints on black faculty recruitment. A multivariateanalysis examines organizational conditions that promoteor curb these dynamics and their relationship to blackappointments at different tenure levels. Results indicate that although the discipline-specificblack doctoral labor supply is a powerful constraint onthe representation of black faculty, selectiveorganizational contexts are substantial influences as well. Although we find little evidence thatinsulation from competition or segmented faculty labormarkets influence the racial composition of faculties,black faculty are more often found whereinstitutionalized discrimination may be checked by greaterformalization and black constituencies on campus.Consistent with statistical discrimination, blackfaculty are poorly represented at research-orientedinstitutions, even controlling for the scholarly reputationof doctoral credentials. 相似文献
124.
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
125.
126.
Tree-structured vector quantization (VQ) is a technique designed to represent a codebook that simplifies encoding as well as vector quantizer design. Most design algorithms for tree-structured VQ used in the past are based on heuristics that successively partition the input space. Recently, Chou, Lookabaugh and Gray proposed a tree-pruning heuristic in which a given initial tree is pruned backwards according to certain optimization criterion. We define the notion of an optimal pruned tree subject to a cost constraint and study the computational complexity of finding such an optimal tree for various cost functions. Under the assumption that all trees are equally probable, we show that, on the average, the number of pruned trees in a given tree is exponential in the number of leaves. Furthermore, we prove that finding an optimal pruned tree subject to constraints such as entropy or the expected-depth is NP-hard. However, we show that when the constraint is the number of leaves, the problem can be solved in polynomial time. We develop an algorithm to find the optimal pruned tree in O(nk) time, where n is the size of the initial tree and kis the constraint size. 相似文献
127.
Students rarely ask questions related to course content in large-format introductory classes. The use of a Web-based forum devoted to student-generated questions was explored in a second-semester introductory biology course. Approximately 80% of the enrolled students asked at least one question about course content during each of three semesters during which this approach was implemented. About 95% of the students who posted questions reported reading the instructor's response to their questions. Although doing so did not contribute to their grade in the course, approximately 75% of the students reported reading questions posted by other students in the class. Approximately 60% of the students reported that the Web-based question-asking activity contributed to their learning of biology. 相似文献
128.
Many short-duration science outreach interventions have important societal goals of raising science literacy and increasing the size and diversity of the science workforce. Yet, these long-term outcomes are inherently challenging to evaluate. We present findings from a qualitative research study of an inquiry-based, life science outreach program to K-12 classrooms that is typical in design and excellent in execution. By considering this program as a best case of a common outreach model, the "scientist in the classroom," the study examines what benefits may be realized for each participant group and how they are achieved. We find that K-12 students are engaged in authentic, hands-on activities that generate interest in science and new views of science and scientists. Teachers learn new science content and new ways to teach it, and value collegial support of their professional work. Graduate student scientists, who are the program presenters, gain teaching and other skills, greater understanding of education and diversity issues, confidence and intrinsic satisfaction, and career benefits. A few negative outcomes also are described. Program elements that lead to these benefits are identified both from the research findings and from insights of the program developer on program design and implementation choices. 相似文献
129.
Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs 总被引:10,自引:0,他引:10
Early DM Maxwell KL Burchinal M Alva S Bender RH Bryant D Cai K Clifford RM Ebanks C Griffin JA Henry GT Howes C Iriondo-Perez J Jeon HJ Mashburn AJ Peisner-Feinberg E Pianta RC Vandergrift N Zill N 《Child development》2007,78(2):558-580
In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children. 相似文献
130.
Sexual and physical abuse history and adult sexual risk behaviors: relationships among women and potential mediators 总被引:1,自引:0,他引:1
OBJECTIVE: While research has supported associations between experiencing abuse and engaging in risky sexual behaviors during adolescence, research regarding these associations among adult women is much more equivocal. In addition, few studies have attempted to identify potential pathways from abuse experiences to sexual risk behaviors. The current study examined the associations between a history of physical or sexual abuse and recent sexual risk behaviors among adult women. Additionally, this study evaluated binge drinking and depressive symptomatology as potential mediators of any relationships between abuse history and sexual risk behaviors. METHODS: A total of 1,428 women between 18 and 40 years of age attending family planning clinic appointments completed a self-report survey regarding their recent sexual behaviors and sexual and physical abuse history. Logistic regressions using backward elimination were conducted to identify factors associated with sexual risk behavior. RESULTS: A history of physical abuse by a romantic partner was associated with several sexual risk behaviors. Few significant associations between intrafamilial physical or sexual abuse and recent sexual risk behaviors were found. Additionally, there was no evidence that these relationships were mediated by binge drinking or depressive symptomatology. CONCLUSIONS: Familial abuse experiences are not necessarily associated with recent sexual risk behaviors among adults. In contrast, physical abuse experiences, particularly those perpetrated by a romantic partner, are associated with engaging in adult sexual risk behaviors among women. However, these associations are not mediated by alcohol use or depressive symptomatology. 相似文献