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91.
This study used data from the Panel Study of Income Dynamics and its 1997 Child Development Supplement to examine how family income matters for young children's development. The sample included 753 children who were between ages 3 and 5 years in 1997. Two sets of mediating factors were examined that reflect two dominating views in the literature: (1) the investment perspective, and (2) the family process perspective. The study examined how two measures of income (stability and level) were associated with preschool children's developmental outcomes (Woodcock-Johnson [W-J] Achievement Test scores and the Behavior Problem Index [BPI]) through investment and family process pathways. Results supported the hypothesis that distinct mediating mechanisms operate on the association between income and different child outcomes. Much of the association between income and children's W-J scores was mediated by the family's ability to invest in providing a stimulating learning environment. In contrast, family income was associated with children's BPI scores primarily through maternal emotional distress and parenting practices. Level of income was associated with W-J letter-word scores and income stability was associated with W-J applied problem scores and BPI, even after all controls were included in the models.  相似文献   
92.
学习型组织,根据六条相互补充的行为准则来设计:创造不断学习的机会。促进探讨和对话。鼓励共同学习和团队学习。建立学习及学习共享系统。促使成员迈向共同愿景。使组织和环境结合起来。  相似文献   
93.
佛教中的体验与“家庭相似性”关联何在,为之辩护的论题包括两部分:(1)与其他方式相比,把皈依概念和神迹概念纳入体验概念可以使我们对佛教体验形成一种更为恰当的观点,而这一观点能够表明佛教的宣称与科学的经验主义的宣称之间的区别(前提1-10);(2)关于界定体验之所是的“家族相似性”理念,本文结论是,皈依与神迹是对佛教中的体验所作出的非实在论的“家族相似性”定义中的两个要素(前提11-13).  相似文献   
94.
This study tests the hypothesis that, during adolescence, antisocial behavior becomes positively associated with peer acceptance. This hypothesis was tested considering both classroom and out-of-class peer relations. Data from a previously published study, with a cross-sectional sample of 577 Italian 11- to 13-year-olds, were used. Analyses showed that in the 6th grade antisocial behavior was negatively related to classroom peer preference, but not significantly related to out-of-class peer inclusion. By the 8th grade, antisocial behavior was positively related to out-of-class peer inclusion, but not significantly related to classroom peer preference. Similar results were found for males and females. The higher level of peer acceptance among the 8th grade antisocial individuals was primarily due to nominations received by other antisocial individuals.  相似文献   
95.
过去三十年来有关数学教育的研究数量急剧增长 .这些研究结果 ,以及在其他领域 ,比如认识心理学上的相关研究结果 ,都被用来确认成功的教学策略和实践 .数学的教和学是复杂的任务 .很难确认一个单一教学行为的变化对学生学习的影响 .这是因为与之相联的其他教学活动 ,以及教学进行时的情景同时也对学生学习有影响 .这些研究结果表明 ,当教师努力想改进自己的数学教学行为时 ,某些教学策略和方法值得仔细地考虑 .对要了解下述建议的读者来说 ,很清楚 ,许多教学行为都是相关的 .有相当一批不同的教学行为已被确认为是有效的教学行为 ,因此许多…  相似文献   
96.
In this paper we study the scaling behavior of nucleotide cluster in 11 chromosomes of Encephalitozoon cuniculi Genome. The statistical distribution of nucleotide clusters for 11 chromosomes is characterized by the scaling behavior of P(S) ∝ e^-αs' where S represents nucleotide cluster size. The cluster-size distribution P(S1+S2) with the total size of sequential C-G cluster and A-T cluster S1+S2 were also studied. P(S1+S2) follows exponential decay. There does not exist the case of large C-G cluster following large A-T cluster or large A-T cluster following large C-G cluster. We also discuss the relatively random walk length function L(n) and the local compositional complexity of nucleotide sequences based on a new model. These investigations may provide some insight into nucleotide cluster of DNA sequence.  相似文献   
97.
To what extent do children with autism (AD) versus typically developing children (TD) rely on attentional and intentional cues to learn words? Four experiments compared 17 AD children (M age=5.08 years) with 17 language- and 17 mental-age-matched TD children (M ages=2.57 and 3.12 years, respectively) on nonverbal enactment and word-learning tasks. Results revealed variability in all groups, but particularly within the AD group. Performance on intention tasks was the most powerful predictor of vocabulary in the AD group but not in the TD groups. These findings suggest that word learning cannot be explained exclusively by either attentional or intentional processes, and they provide evidence of a special role for intentional understanding in the vocabulary development of AD children.  相似文献   
98.
The following project aimed at promoting integrated and long-lasting learning is described for an Immunology course, but it may be adapted to other disciplines. Students were asked to develop and carry out a research project to examine the relationship between immune function and stress. The experiments were required to include the assessment of salivary cortisol and salivary IgA (sIgA) with enzyme immunoassays. All other aspects of the experiments were developed by student groups with appropriate guidance from the instructor. Data are presented for one group project that assessed the effect of music on cortisol and sIgA. Overall levels of sIgA and cortisol were consistent with reported values. Students found a significant decrease in cortisol over time. Additionally, there was a trend that supported the overall student hypothesis regarding the effect of stress and immune function. Compared with the same Immunology course that included an instructor-designed experiment using enzyme immunoassays for cortisol and sIgA, several assessments (e.g., final grades and comments on student evaluations) show that overall learning seemed to be much better in the course with the student-directed research project.  相似文献   
99.
In this paper,we investigate the effect and the possible mechanism of high glucose levels on the calcification of human aortic smooth muscle cells (HASMCs).HASMCs were divided into four groups: normal glucose group (NG),osmolality control group (OC),high glucose group (HG,HASMCs culture medium containing 30 mmol/L glucose),and high glucose plus recombinant human Noggin protein (bone morphogenetic protein-2 (BMP-2) antagonist) group (HN).The mRNA levels and the protein expressions of BMP-2 and core binding factor alpha-1 (Cbfα-1) were measured by real-time quantitative polymerase chain reaction (PCR) and Western blot.After induced by 10 mmol/L β-glycerol phosphoric acid,cells were harvested for assessments of alkaline phosphatase (ALP) activities at Days 1,2,and 3,and intracellular calcium contents at Days 7 and 14,respectively.High glucose levels increased the mRNA levels and the protein expressions of BMP-2 and Cbfα-1 (P0.05).The expression of Cbfα-1 was partially blocked by Noggin protein (P0.05),while BMP-2 was not (P0.05).After being induced by β-glycerol phosphoric acid,high glucose levels increased the ALP activity [(48.63±1.03) vs.(41.42±2.28) U/mg protein,Day 3;P0.05] and the intracellular calcium content [(2.76±0.09) vs.(1.75±0.07) μmol/mg protein,Day 14;P0.05] in a time-dependent manner when compared with the NG group,while the ALP activity could not be blocked by Noggin protein [(48.63±1.03) vs.(47.37±0.97) U/mg protein,Day 3;P0.05].These results show that high glucose levels can evoke the calcification of HASMCs by inducing osteoblastic trans-differentiation and intracellular calcium deposition via the BMP-2/Cbfα-1 pathway,which can be partially blocked by Noggin protein.  相似文献   
100.
BACKGROUND: Because of the expense of updating practice guidelines, recent attention has focused on approaches that can reliably assess any updating required. Shekelle et al. (Journal of the American Medical Association 2001, 286, 1461-7) proposed using limited literature searches with expert involvement to reduce resources used in assessing whether a guideline needs updating. OBJECTIVES: This study compared Shekelle's method and the traditional systematic review method regarding comprehensiveness and effort. METHODS: Two research teams translated critical key questions on screening test treatments and outcomes to Medical Subjects Headings (MeSH) and search strategies. They refined Shekelle's method over three iterations, seeking greater efficiency. Using both methods independently, teams assessed the need to update six topics from the 1996 Guide to Clinical Preventive Services (US Preventive Services Task Force). Outcomes included completeness of study identification, importance of missed studies and effort involved. RESULTS: The revised review approach produced fewer citations than the traditional approach and saved time, identifying fewer eligible studies than the traditional approach. None of the studies missed was rated important by the experts consulted. CONCLUSIONS: The revised review approach provides an acceptable method for judging whether a guideline requires updating. Librarians were an integral part of the research process that streamlined the searches.  相似文献   
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