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91.
In the knowledge economy, now more than ever, students are encouraged to attend an institution of higher education. Students actively search for resources to assist them in their progress toward a college degree, even before high school graduation. Dual enrollment is an opportunity for students to complete college courses while still in high school, and it encourages stronger collaborations between K–12 and higher education. The purpose of this study was to explore the relationship between demographic and policy variables in South Carolina technical college dual enrollment programs and first-to-second-year persistence of dually enrolled students once entering college. All participants in this study were high school students who continued at a technical college after graduation. Outcomes were analyzed using logistic regression to determine persistence, defined as first-to-second-year retention. Variables included dual enrollment course type, course setting, ethnicity, gender, and county of residence. Results show that course type and course setting are significant in predicting college student persistence. Recommendations and implications for future research are discussed.  相似文献   
92.
A universal coagulation test that reliably detects prolonged coagulation time in patients, irrespective of the anticoagulant administered, has not been available to date. An easily miniaturised, novel μ-fluidic universal coagulation test employing surface acoustic waves (SAW) is presented here. SAW was employed to instantly mix and recalcify 6 μl citrated whole blood and image correlation analysis was used to quantify clot formation kinetics. The detection of clinically relevant anticoagulant dosing with old anticoagulants (unfractionated heparin, argatroban) and new anticoagulants (dabigatran, rivaroxaban) has been tested and compared to standard plasma coagulation assays. The applicability of this novel method has been confirmed in a small patient population. Coagulation was dose-proportionally prolonged with heparin, argatroban, dabigatran, and rivaroxaban, comparable to standard tests. Aspirin and clopidogrel did not interfere with the SAW-induced clotting time (SAW-CT), whereas the strong GPIIb/IIIa-inhibitor abciximab did interfere. Preliminary clinical data prove the suitability of the SAW-CT in patients being treated with warfarin, rivaroxaban, or dabigatran. The system principally allows assessment of whole blood coagulation in humans in a point-of-care setting. This method could be used in stroke units, emergency vehicles, general and intensive care wards, as well as for laboratory and home testing of coagulation.  相似文献   
93.
Abstract

This study aimed to produce age- and sex-specific physical fitness reference data for Portuguese youth; to report the prevalence of youth in the healthy zone of physical fitness according to the FITNESSGRAM® criteria; to verify the agreement between the Portuguese physical fitness percentiles and the FITNESSGRAM® healthy zones. In 2008, 22,048 Portuguese children and adolescents (10–18 years) were evaluated. Physical fitness (curl-ups, push-ups, 20-m shuttle run and modified-back-saver-sit-and-reach tests) was evaluated using the FITNESSGRAM® Test Battery 8.0. Smoothed percentile curves were estimated using Cole’s LMS method. Boys consistently outperformed girls in every physical fitness test, except for the modified-back-saver-sit-and-reach tests. In both sexes and for all physical fitness tests, higher percentile values were observed at older ages. The 50th percentile of all physical fitness tests had the highest accuracy to discriminate between under healthy zone and healthy zone of the FITNESSGRAM®. Portuguese schools and physical education teachers may considerer the 50th percentile for age and sex or the FITNESSGRAM® criteria for classifying participants in the healthy zone as acceptable cut-offs, above which youth should be considered fit. These reference values can be used as normative data and for baseline values for subsequent surveillance of the physical fitness of Portuguese youth.  相似文献   
94.
Abstract

This study aimed to investigate the direct and indirect associations between perceived environmental characteristics and psychosocial factors and physical activity levels in adolescents from Northeast Brazil. The sample was composed of 2,361 adolescents aged 14–19 years (56.6% female). Physical activity was measured using a questionnaire and environmental (perceived environmental characteristics) and psychosocial (self-efficacy, social support from parents and friends for physical activity) factors with previously validated scales. Perceived environmental characteristics were not directly associated with the levels of physical activity, but exhibited significant indirect associations, mediated by self-efficacy in males. Self-efficacy and social support were positively and directly associated with physical activity levels, and part of the associations between social support and physical activity was mediated by self-efficacy. Perception of self-efficacy and social support, important factors associated with physical activity levels in adolescents, should be the target of interventions aimed at increasing physical activity. Favorable environments for physical activity also need to be considered, since they have a positive influence on the self-efficacy of adolescents.  相似文献   
95.
Abstract

The aims of the this prospective study were to analyse physical activity (PA) engagement during the first and second trimesters, considering the different guidelines published on PA, to document the individual characteristics associated with the accomplishment of these guidelines and to examine pregnant women’s perceived barriers to leisure PA, using a socioecological framework. A sample of 133 pregnant women in two stages – at 10–12 weeks’ gestation (T1) and 20–22 weeks’ gestation (T2) – were evaluated. PA was assessed by accelerometry during the T1 and T2 evaluation stages. Socio-demographic characteristics, lifestyle factors and barriers to leisure PA were assessed via questionnaire. A large proportion of women (ranging from 32% to 96%) did not reach the levels of PA recommended by the guidelines. There were no significant differences between T1 and T2 with regard to compliance with PA recommendations. A decrease in PA levels from T1 to T2 was noted for all recommendations. No associations were found between participants’ characteristics and adherence to the recommendations in T1 and T2. No significant differences were found in barriers to leisure PA between T1 and T2. The most commonly reported barriers to leisure PA were intrapersonal, not health related. Our results indicate that there were no differences between trimesters regarding compliance of PA recommendations, and perceived barriers were similar in both trimesters.  相似文献   
96.
In an attempt to build a more comprehensive and holistic understanding of the complexity, dynamics and idiosyncrasies involved in becoming a teacher, this study focussed on the experiences of 295 student teachers. Their feelings, cognitions and perceptions regarding teaching practice were analysed using the short version of the Inventory of Experiences and Perceptions of the Teaching Practice. Results emphasise some of the difficulties experienced during this period (e.g., stress, sense of weariness and ‘vulnerability’), as well the positive perceptions of these student teachers regarding their growing knowledge and skilfulness, as well as their sense of efficacy, flexibility and spontaneity in their performance and interactions. Their perception of their accomplishments in achieving reasonable levels of acceptance and recognition within the school community and their positive evaluation of the guidance and support provided by their supervisors are also emphasised. Differences were found – in terms of gender and graduate course background – in the way these student teachers experienced some aspects of teaching practice.  相似文献   
97.
The aim of this study is to assess the impact of PISA (Programme for International Student Assessment) on international scientific journals. A bibliometric analysis was conducted of publications included in three main scientific publication databases: Eric, EBSCOhost and the ISI Web of Knowledge, from 2002 to 2010. The paper focused on four main questions: who carried out these studies, in which academic journals have the articles been published, what has been the evolution of these publications and what were the main article topics? The study concludes that PISA has had a considerable impact on the scientific research, reflected primarily by university-based authors from the areas of education and social sciences analysing student performance. The evolution since 2007 seems to indicate that more articles will be published in coming years through the initiative of researchers (rather than the editorial boards), even from other scientific areas, thus increasing the number of topics of analysis.  相似文献   
98.

In this article we analyse the interaction between a high school chemistry teacher and her students from two different classes, emphasizing how emotions, affects and feelings contributed to, or obstructed, the dynamic of interactions. The data come from an ethnographic research approach and include videotapes of the lessons, interviews and field notes. Using the distinction introduced by Damasio between primary and secondary emotions, and between emotions and feelings, we describe how the background feelings emerged in different ways in the two classrooms. In class B, the relationships were constructed in a friendly way from the very beginning. The positive emotions that contributed to raising positive background feelings occurred in a high number and frequency. In class A, the picture was completely different, with a higher number and frequency of negative emotions. Thus, emotions and background feelings that were constructed differently in each classroom were at the heart of the different outcomes in terms of attitudes towards chemistry that arose in the two classrooms. In the paper, we also discuss the implication of this kind of analysis for science teaching generally.  相似文献   
99.
Australian, Iranian and Portuguese university students (n?=?967) completed the University Students Depression Inventory (USDI) in English, Persian and Portuguese languages, respectively. A series of MANOVA analyses were used to examine differences in depression symptoms as an effect of the country and demographic variables. Interactions were also examined. The results indicated that country, gender and year level had some impact on the depressive symptoms of the university students. Australian students were more depressed than the Iranian and Portuguese students, while Iranian students were more depressed than the Portuguese students. Sub-scales of USDI – Lethargy, Motivation and Cognitive/Emotional – were also used to compare the depressive symptoms of students. The Australian female students reported a significantly higher level of lethargy than their male counterparts. Similarly, the first-year male students from Iran were significantly more lethargic than the first-year Iranian female students. Iranian and Portuguese male students, compared to the female students of these countries, experienced a lower level of motivation. The Australian and Iranian students, compared to the Portuguese students, reported a significantly higher level of cognitive and affective symptoms. The scores on the Cognitive/Emotional sub-scale increased with the year level. Differences among students' depression are described and implications discussed.  相似文献   
100.
Coastal tidal wetlands produce and accumulate significant amounts of organic carbon (C) that help to mitigate climate change. However, previous data limitations have prevented a robust evaluation of the global rates and mechanisms driving C accumulation. Here, we go beyond recent soil C stock estimates to reveal global tidal wetland C accumulation and predict changes under relative sea level rise, temperature and precipitation. We use data from literature study sites and our new observations spanning wide latitudinal gradients and 20 countries. Globally, tidal wetlands accumulate 53.65 (95%CI: 48.52–59.01) Tg C yr−1, which is ∼30% of the organic C buried on the ocean floor. Modeling based on current climatic drivers and under projected emissions scenarios revealed a net increase in the global C accumulation by 2100. This rapid increase is driven by sea level rise in tidal marshes, and higher temperature and precipitation in mangroves. Countries with large areas of coastal wetlands, like Indonesia and Mexico, are more susceptible to tidal wetland C losses under climate change, while regions such as Australia, Brazil, the USA and China will experience a significant C accumulation increase under all projected scenarios.  相似文献   
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