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31.
西准噶尔萨吾尔地区地处新疆阿勒泰地区吉木乃县及塔城地区和丰县。酸性侵入岩在区内较发育,其研究对于准噶尔地区后碰撞构造一岩浆演化时限的厘定具有重要的意义。塔斯特岩体是萨吾尔地区重要的复式花岗岩体,与区内铜、金矿化关系密切。塔斯特岩体锆石LA-ICPMS年龄为337±4Ma(1δ),形成于早石炭世。结合已有的地球化学特征研究,这一年龄显示西准噶尔地区在早石炭世已处于后碰撞环境。本文获得的塔斯特岩体成岩年龄是目前在准噶尔地区获得的最老的后碰撞花岗岩锆石U-Pb年龄之一,为准噶尔地区后碰撞构造-岩浆演化时限的厘定提供了新的证据。 相似文献
32.
Jackson R Baird W Davis-Reynolds L Smith C Blackburn S Allsebrook J 《Health information and libraries journal》2007,24(2):95-102
OBJECTIVES: The objectives of this work were to identify the sources of information currently received, information-seeking behaviours, information requirements and preferences for future information provision amongst health and social care professionals providing care to children with health care needs. METHODS: Data were collected using a cross-sectional postal questionnaire survey. RESULTS: A wide range of information resources was reported as being available to professionals. However, a large proportion of respondents found it necessary to perform additional searches for information, suggesting that current resources were not satisfying their needs. The majority of professionals reported a preference for electronic formats, whilst a smaller proportion preferred hard copy materials. Participants promoted the use of informal networks as a means of support and exchange of information. CONCLUSION: Supplementing the information that is provided in electronic and hard copy formats, by enhancing informal networks, may be the most effective way of meeting the information needs of this group of professionals. 相似文献
33.
Objectives: To explore how the library service expectations and perceptions of users might differ across health‐related libraries as against major research libraries not operating in a medical context; to determine whether users of medical libraries demand better library service quality, because the inability of users to access needed literature promptly may lead to a patient who cannot be properly diagnosed, or a diagnosis that cannot be properly treated. Methodology: We compared LibQUAL+® total and subscale scores across three groups of US, Canadian and British libraries for this purpose. Results: Anticipated differences in expectations for health as other library settings did not emerge. Conclusions: The expectations and perceptions are similar across different types of health science library settings, hospital and academic, and across other general research libraries. 相似文献
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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
36.
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
37.
Factors that influence the incidence of utilization deficiencies and other recall/strategy-use patterns on a strategic memory task were evaluated in two hundred and fourteen 7- and 9-year-old children. Both utilization deficiencies and the incidence of children showing increases in both recall and strategy use over phases were more likely to be observed on phase transitions involving prompting or when different lists of items were included on consecutive trials; in contrast, increases in recall in the absence of increases in strategy use were more likely to be found between trials consisting of the same stimulus items. This research clearly indicates that patterns of recall/strategy-use relations, including utilization deficiencies, vary meaningfully with the age of the child and a variety of contextual factors. 相似文献
38.
This longitudinal study of 105 economically disadvantaged children examined the relation between reading problems and internalizing behavior in 3rd- and 5th-grade assessments (8- to 12-year olds). The variable-centered results showed that reading problems predicted change in internalizing behavior in the context of child and family predictors. The person-centered results showed that children with reading problems in both grades had higher internalizing scores in 5th grade but not in 3rd grade than children with reading problems in 3rd grade or no problems. Child-reported negative emotion experiences varied similarly across grade. The results tie reading problems to emotional distress in school and support conclusions about the direction of effects and the internalization of academic difficulty for disadvantaged children. 相似文献
39.
Early adolescents' (11-14 years) responses to marital hostility were examined in a sample of 416 families. The cognitive-contextual perspective and emotional security hypothesis guided the study and 9 adolescent responses were identified. Prospective associations were examined in several structural equation models that included adolescent problems as outcomes. Self-blame and perceived threat uniquely mediated the association between Year 1 marital hostility and Year 3 adolescent externalizing problems (p<.05). Self-blame, lower constructive representations, internalization of feelings, avoidance, and emotional dysregulation uniquely mediated the association between Year 1 marital hostility and Year 3 internalizing problems. Specific cognitive and emotionally based responses are important to understanding how martial hostility affects youth and need to be considered within an integrated model. 相似文献
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