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The goals of this research were to explore the current literature regarding associations between psychological stress and adverse fetal outcome, associations between aerobic exercise and psychological stress reduction, and associations between aerobic exercise and fetal outcome. The published studies that were located provide evidence of the following: 1) Stress reactivity increases physiologically during pregnancy, 2) pregnant women may experience additional stressors that are usually not experienced in a nonpregnant state, 3) psychological stress in pregnancy is associated with adverse fetal outcome, 4) exercise can be a method of stress reduction, 5) exercise in pregnancy is not associated with adverse fetal outcome, and 6) exercise in pregnancy may provide benefit to the fetus. Data were analyzed from an original study and associations were reported between psychological stress-management activities and participation in aquatic aerobic exercise classes. No reports were available investigating an exercise-induced reduction in psychological stress with fetal outcome.  相似文献   
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ABSTRACT

The Colorado Reading to Ensure Academic Development Act requires grade-level attainment in literacy in English for students in grades K-3. Its practical outcome, however, has been to pressure schools with bilingual programs to shift their instructional language allocations towards more English in the early grades. Proposed rule revisions debated by the state Board of Education sought to facilitate testing in students’ language of instruction for those in bilingual programs. Analysis of written and verbal opposition to the proposed rule revisions demonstrates the persistence of insidious ethnoculturalist discourses opposing bilingual education as well as the cooptation of liberal multiculturalist discourses that, while framing bilingualism as an asset, argue that it is underdeveloped in bilingual programs that do not include English instruction from the outset. Given that bilingual instruction has demonstrated time and again that it benefits students acquiring English in schools, such new discursive turns pose a threat that must be recognized to fend off further legislative and regulatory attempts against bilingual education.  相似文献   
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This Youth Participatory Action Research (YPAR) study represents a collaboration with six students from alternative education to inquire about the experiences of vulnerable youth – students in alternative education and youth who have dropped out of school. Utilizing the Enhanced Critical Incident Technique, youth researchers asked their peers what helped and hindered their retention and success in mainstream and alternative education. Youth researchers engaged in authentic participation and took part in the iterative phases of YPAR – critical reflection and social action. Their involvement empowered them to advocate for their peers by disseminating the results and recommendations to key stakeholders within the community. Youth researchers conducted semi-structured interviews with 18 participants. Overall, the findings show that relationships with staff and peers, flexibility, psychosocial and academic supports, and personal circumstances are vital in helping vulnerable students succeed in school. Engagement in YPAR provided insight into working with vulnerable youth in a manner that promotes agency and social change within educational institutions.  相似文献   
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The research investigated the association between school engagement and adult education and occupation outcomes, within the context of a 1985 Australian longitudinal national cohort study of the factors affecting children's long‐term health and well‐being. School engagement may be more modifiable than other factors related to academic success, such as academic attainment, which is influenced by family background. A School Engagement Index was constructed using questionnaire items on school enjoyment and boredom. Related school engagement items included learner self‐concept, motivation to learn, sense of belonging, participation in school or extra‐mural activities, and enjoyment of physical activity. In 2004–2006, participants (aged 26 to 30 years) reported their highest level of education achieved and current occupation. Potential covariates included age, sex, markers of socio‐economic status in childhood, personality and school‐level variables (i.e., number of students, single sex versus co‐education; government, private or independent). Logistic regression was used to estimate the odds of achieving post‐compulsory school education and achieving higher status occupations. Findings revealed that each unit of school engagement was independently associated with a 10% higher odds (OR 1.10 95% CI 1.01,1.21) of achieving a post‐compulsory school education. Maternal education, self‐concept as a learner, motivation to learn, all also significantly predicted achieving post‐compulsory school education. School engagement was found to mediate the association between the personality characteristic of agreeableness and education outcomes. Higher school engagement was also independently associated with achieving higher status occupations 20 years later (OR 1.11 95% CI 1.03, 1.20). Importantly, this was independent of a host of background factors.  相似文献   
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In a microgrid (MG) topology, the secondary control is introduced to compensate for the voltage amplitude and frequency deviations, mainly caused by the inherent characteristics of the droop control strategy. This paper proposes an accurate approach to derive small signal models of the frequency and amplitude voltage at the point of common coupling (PCC) of a single-phase MG by analyzing the dynamics of the second-order generalized integrator-based frequency-locked loop (SOGI-FLL). The frequency estimate model is then introduced in the frequency restoration control loop, while the derived model of the amplitude estimate is introduced for the voltage restoration loop. Based on the obtained models, the MG stability analysis and proposed controllers’ parameters tuning are carried out. Also, this study includes the modeling and design of the synchronization control loop that enables a seamless transition from island mode to grid-connected mode operation. Simulation and practical experiments of a hierarchical control scheme, including traditional droop control and the proposed secondary control for two single-phase parallel inverters, are implemented to confirm the effectiveness and the robustness of the proposal under different operating conditions. The obtained results validate the proposed modeling approach to provide the expected transient response and disturbance rejection in the MG.  相似文献   
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This study tests the agenda-setting hypothesis for the environmentalissue in Hong Kong from 1983 to 1995. It was found that theagenda-setting hypothesis was supported for the initial periodof five and a half years. In the subsequent period of sevenand a half years, despite the increased media coverage of theissues, there was a significant drop in the perceived salienceof the environmental problem. This may be due to the dilutionof public attention as a result of diversity in the news agendaand reporting of local environmental problems as ‘soft’news. It was also found that the environmental issue failedto compete with other prominent issues directly affecting thepublic. The mass media played a much less important role inkeeping the environmental issue on the public agenda at thelater stage.  相似文献   
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The University of Florida offers an online professional practice Ed.D. focused on Educational Technology. Twenty-three students have completed professional practice dissertations and graduated since the program’s inception in 2008. The purpose of this article is to share what these dissertations have looked like and to begin a dialogue about professional practice dissertations completed in online educational technology programs. Specifically, we (1) provide an overview of different ways professional practice Ed.D. dissertations are structured, (2) share guiding principles for professional practice dissertations in our Ed.D. program, (3) analyze the ways in which these guiding principles played out in the dissertations and (4) discuss the implications of our analysis for our program and for other online professional practice programs in Educational Technology.  相似文献   
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Tumor necrosis factor (TNF-α) is a cytokine involved in systemic inflammation during acute phase reactions. The current study was designed to investigate the levels of pro-inflammatory cytokine (TNF-α) along with the anti-inflammatory cytokine (IL-10) during progression of non-alcoholic fatty liver disease (NAFLD) from simple steatosis to non-alcoholic steatohepatitis (NASH) and fibrosis in diabetic patients, and correlate the levels of cytokines with the progression of NAFLD. Fifty-two diabetic patients compared to 18 healthy controls were participated in this study. Based on clinical diagnosis, patients were divided into three groups: simple steatosis, NASH and fibrosis. Serum liver function tests, fasting blood glucose, bilirubin, ALT, AST, TNF-α, IL-10 and lipid profile were measured. TNF-α levels were significantly higher in NAFLD patients compared to control subjects with a significant positive correlation with body mass index and fasting blood glucose (FBG) but with negative correlation with IL-10. Serum IL-10 levels were significantly lower in NAFLD patients compared with controls. A positive correlation between IL-10 and HDL-C with concomitant negative correlation between IL-10 and FBG and triacylglycerides was found. Cytokine analyses showed that there was a prominent imbalance between TNF-α and IL-10 in patients with NAFLD, and this imbalance increase by increasing the progression of NAFLD especially in obese diabetic patients. TNF-α and IL-10 could be used in diagnosis and follow-up of NAFLD stages in a way to avoid liver biopsies in greater proportion of patients.  相似文献   
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