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11.
Does a national research-focused organization need a technically competent leader? This study provides preliminary answers to that question using a natural experiment underway at the Department of Energy (DOE): a leader with significant high-level management experience superior to that of his predecessors, but no relevant technical experience was appointed to run the vast scientific research operation. The following hypothesis is proposed: A major risk of allowing technically-unqualified leadership is that an amateur can be more easily manipulated by special interests against the best interests of the nation. The hypothesis is tested by technically analyzing three case studies on proposals from the Secretary of Energy. The results show 1) requests for budget cuts undermining DOE's mission, 2) requests for redundant studies wasting DOE resources, and 3) counter-productive recommendations derived from a misrepresentation of the studies' results, which indicate technical competence is important for DOE leadership. These preliminary results indicate technical competency is important for leaders running organizations that oversee research. Finally, a potential policy safe guard to the risks of extreme technical incompetence is provided, which can be applied to either independent- or politically-appointed bureaucrats.  相似文献   
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Using objectification theory (Fredrickson & Roberts, 1997), this study tested the interaction between self-objectification, appearance evaluation, and self-esteem in predicting body satisfaction and mood states. Participants (N = 93) were physically active female university students. State self-objectification was manipulated by participants wearing tight revealing exercise attire (experimental condition) or baggy exercise clothes (control condition). Significant interactions emerged predicting depression, anger, fatness, and satisfaction with body shape and size. For participants in the self-objectification condition who had low (as opposed to high) appearance evaluation, low self-esteem was associated with high depression, anger, and fatness and low satisfaction with body shape and size. In contrast, for participants with high self-esteem, these mood and body satisfaction states were more favorable irrespective of their levels of appearance evaluation. For female exercisers, self-esteem-enhancing strategies may protect against some of the negative outcomes of self-objectification.  相似文献   
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OBJECTIVE: The prevalence of childhood sexual abuse among Latino adult men who have sex with men who live in the US was estimated because a history of childhood sexual abuse increases HIV sexual risk behaviors and other negative health outcomes in adulthood. METHOD: The Urban Men's Health Study is a random-digit telephone probability survey of 2881 adult men who have sex with men (MSM) aged 18 years or older residing in San Francisco, New York, Los Angeles, and Chicago. Self-reported history of childhood sexual abuse was the main outcome measure gathered from 2692 MSM. RESULTS: A significantly higher proportion of Latino MSM reported sexual abuse before age 13 (22%) than did non-Latino MSM (11%). CONCLUSIONS: Latino MSM are twice as likely to report a history of childhood sexual abuse than are non-Latino MSM. Given the association between childhood sexual abuse and increased risk for HIV and other negative health outcomes, health providers must remain vigilant to the possibility of childhood sexual abuse histories among their Latino patients.  相似文献   
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OBJECTIVE: This study examined risk of placement disruption and negative placement outcomes (e.g., residential treatment and incarceration) among adolescents placed in traditional family foster care for a year or longer. A foster parent's report of externalizing behavior problems was expected to be a stronger predictor of disruption and negative outcomes than a caseworker's report. Additionally, the association between behavior problems and placement disruption was expected to be mediated by the youth's degree of belonging and integration in the foster home. METHOD: The caseworkers and foster parents of 179 randomly selected 12-13-year-old adolescents placed in traditional foster care were interviewed by telephone. Interviews included standardized measures of externalizing behavioral problems and several other variables that have been previously associated with placement movement. Disruption from the youth's foster home at the time of the interview was prospectively tracked for 5 years. RESULTS: Over half of the youth experienced a disruption of their placement. Contrary to expectations, behavior problems as reported by caseworkers, but not foster parents, were predictive of placement disruption. However, the foster parent's report of behavior problems predicted risk of negative outcome after a period of 5 years. As hypothesized, integration in the foster home was highly predictive of placement stability and mediated the association between behavior problems and risk of disruption. CONCLUSIONS: Results suggest that integration in the foster home might be an important dimension of placement adaptation that should be considered during service planning for foster youth in long-term foster care. In addition, using standardized measures of behavior with both foster parents and caseworkers might be necessary to assess both long-term risk of negative outcomes and more immediate risk of placement disruption.  相似文献   
15.
When missingness is suspected to be not at random (MNAR) in longitudinal studies, researchers sometimes compare the fit of a target model that assumes missingness at random (here termed a MAR model) and a model that accommodates a hypothesized MNAR missingness mechanism (here termed a MNAR model). It is well known that such comparisons are only interpretable conditional on the validity of the chosen MNAR model’s assumptions about the missingness mechanism. For that reason, researchers often perform a sensitivity analysis comparing the MAR model to not one, but several, plausible alternative MNAR models. In the social sciences, it is not widely known that such model comparisons can be particularly sensitive to case influence, such that conclusions drawn could depend on a single case. This article describes two convenient diagnostics suited for detecting case influence on MAR–MNAR model comparisons. Both diagnostics require much less computational burden than global influence diagnostics that have been used in other disciplines for MNAR sensitivity analyses. We illustrate the interpretation and implementation of these diagnostics with simulated and empirical latent growth modeling examples. It is hoped that this article increases awareness of the potential for case influence on MAR–MNAR model comparisons and how it could be detected in longitudinal social science applications.  相似文献   
16.
3D printing technology is a powerful educational tool that can promote integrative STEM education by connecting engineering, technology, and applications of science concepts. Yet, research on the integration of 3D printing technology in formal educational contexts is extremely limited. This study engaged preservice elementary teachers (N?=?42) in a 3D Printing Science Project that modeled a science experiment in the elementary classroom on why things float or sink using 3D printed boats. The goal was to explore how collaborative 3D printing inquiry-based learning experiences affected preservice teachers’ science teaching self-efficacy beliefs, anxiety toward teaching science, interest in science, perceived competence in K-3 technology and engineering science standards, and science content knowledge. The 3D printing project intervention significantly decreased participants’ science teaching anxiety and improved their science teaching efficacy, science interest, and perceived competence in K-3 technological and engineering design science standards. Moreover, an analysis of students’ project reflections and boat designs provided an insight into their collaborative 3D modeling design experiences. The study makes a contribution to the scarce body of knowledge on how teacher preparation programs can utilize 3D printing technology as a means of preparing prospective teachers to implement the recently adopted engineering and technology standards in K-12 science education.  相似文献   
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The results from five experiments are considered in relation to two of Spence's (1937, 1938) proposals concerning discrimination learning. In Experiments 1 and 2, we investigated whether his ideas about the interaction between excitatory and inhibitory generalization gradients can be used to understand how animals solve a complex patterning discrimination. The results supported a development of his proposals as put forward by Pearce (1994), provided a modification was made to Pearce's rulefor determining the shape ofthe generalization gradient. In Experiments 3, 4, and 5, we examined whether animals would pay more attention to stimuli that are relevant, rather than irrelevant, to the solution of a discrimination. The results supported this proposal for stimuli comprising visual patterns, but not for those comprising plain colors. The results also indicated that change of attention was a consequence of preliminary receptor-exposure acts, as envisaged by Spence, and not of more central changes in attention.  相似文献   
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ABSTRACT

Research Findings: The current study examined characteristics of 71 Early Head Start lead teachers in relation to classroom interactions with infants and toddlers. Measured teacher characteristics included education, years of experience, beliefs about child rearing, depressive symptoms, and the temperamental characteristics of positivity and frustration. Teacher–child interactions were measured using the Classroom Assessment Scoring System, Toddler Version (La Paro, Hamre, & Pianta, 2012). Results indicated that field of degree was directly associated with the majority of dimensions of teacher–child interactions. Examination of teachers’ years of experience and intrapersonal characteristics revealed a number of significant interactions, indicating that teacher experience and appropriate beliefs may serve as protective factors in the presence of psychosocial risk factors. Practice or Policy: Overall, our findings suggest that both early childhood education degrees and years of experience are directly or indirectly associated with multiple dimensions of teacher–child interactions, confirming that these patterns established for preschool teachers hold for teachers of infants and toddlers. These results also suggest that years of experience and progressive beliefs about children may be especially important for teachers who are depressed or who have low levels of positivity and high levels of frustration. Implications for future research, as well as preservice and in-service professional development, are discussed.  相似文献   
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