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71.
We analyze longitudinal data from students who spent their academic careers in North Carolina (NC) public secondary schools and attended NC public universities to investigate the importance of high school racial composition and opportunities to learn in secondary school for choosing a science, technology, engineering, and mathematics (STEM) major. We consider school racial composition and opportunities to learn as contexts that shape students' decisions regarding college majors. Results of cross‐classified hierarchical logistic models indicate that attending schools with predominantly White students is negatively associated with declaring a STEM major and with graduating with a STEM major irrespective of students' own race. The finding suggests that for students in North Carolina, attending racially isolated White high schools is related to a decrease in adolescents' participation in STEM during college.  相似文献   
72.
73.
Supervised exercise has shown benefits for subjects with asthma, but little is known about the effectiveness of unsupervised physical activity on this population. We investigated the effects of a 12-week unsupervised pedometer-based physical activity program on daily steps and on clinical and psychological parameters of adults with asthma. Clinically stable adults with moderate to severe asthma were encouraged to take daily 30-minute walks and were randomized to pedometer and control groups. The pedometer group received pedometers and individualized daily step targets. Changes in daily steps (average of steps taken during six consecutive days), six-minute walk test (6MWT), health-related quality of life, asthma control and anxiety and depression levels were assessed 12 weeks after intervention and 24–28 weeks after randomization. Thirty-seven participants were recruited and 30 completed the intervention. At 12 weeks, the groups differed significantly in daily steps (adjusted average difference, 2488 steps; 95% confidence interval [CI], 803 to 4172; p = 0.005) and in the 6MWT (adjusted average difference, 21.9 m; 95% CI, 6.6 to 37.3; p = 0.006). These differences were not significant 24–28 weeks after randomization. The program was effective in increasing daily steps of adults with moderate to severe asthma 12 weeks after intervention.  相似文献   
74.
This study was conducted to determine the effects of inspiratory muscle training (IMT) on respiratory and peripheral muscles oxygenation during a maximal exercise tolerance test and on repeated-sprint ability (RSA) performance in professional women football players. Eighteen athletes were randomly assigned to one of the following groups: SHAM (n = 8) or IMT (n = 10). After a maximal incremental exercise test, all participants performed (on a different day) a time-to-exhaustion (Tlim) test. Peripheral and respiratory muscles oxygenation by near-infrared spectroscopy, breath-by-breath ventilatory and metabolic variables, and blood lactate concentration were measured. The RSA test was performed on a grass field. After a 6 week intervention, all athletes were reevaluated. Both groups showed increases in inspiratory muscles strength, exercise tolerance and RSA performance, however only the IMT group presented lower deoxyhemoglobin and total hemoglobin blood concentrations on intercostal muscles concomitantly to an increased oxyhemoglobin and total hemoglobin blood concentrations on vastus lateralis muscle during Tlim. In conclusion, these results may indicate the potential role of IMT to attenuate inspiratory muscles metaboreflex and consequently improve oxygen and blood supply to limb muscles during high-intensity exercise, with a potential impact on inspiratory muscle strength, exercise tolerance and sprints performance in professional women football players.  相似文献   
75.
Abstract

This study investigated the influence of the regression model and initial intensity during an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and performance in elite-standard runners. Twenty-three well-trained runners completed a discontinuous incremental running test on a treadmill. Speed started at 9 km · h?1 and increased by 1.5 km · h?1 every 4 min until exhaustion, with a minute of recovery for blood collection. Lactate–speed data were fitted by exponential and polynomial models. The lactate threshold was determined for both models, using all the co-ordinates, excluding the first and excluding the first and second points. The exponential lactate threshold was greater than the polynomial equivalent in any co-ordinate condition (P < 0.001). For both models, the lactate threshold was lower when all co-ordinates were used than when the first and the first and second points were excluded (P < 0.001). 10-km race pace was correlated with both the exponential and polynomial lactate thresholds for all the co-ordinate conditions (r ≥ 0.75, < 0.001 and r ≥ 0.56, P < 0.05, respectively). The results suggest that the exponential lactate threshold should be used instead of the polynomial equivalent since it is more strongly associated with performance and is independent of the initial intensity of the test.  相似文献   
76.
Abstract

Exercise performed at a competitive level could deeply modify the immune system and the cytokine response of athletes. In this report, we demonstrated that young elite female artistic gymnasts (n = 16; age: 9–15 years) showed an increase of interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-α) mRNA expression in blood mononuclear cells (PBMCs), in comparison to girls performing the same sport at a recreational level (n = 16; age: 10–15 years). The increase of IL-6 and TNF-α mRNAs appeared to be directly linked to the intensity and duration of the training. Moreover, in elite athletes engaged in artistic gymnastics or in synchronised swimming (n =34; age: 9–15 years), IL-6 gene expression appeared to be modulated by the levels of circulating oestrogens: pre-pubertal athletes (n = 20; age: 11 ± 1 years) revealed a higher increase in IL-6 than pubertal athletes (n = 14; age: 14 ± 1.6 years). In pre-pubertal athletes, body mass index (BMI) percentile was inversely correlated with the increase of both IL-6 and TNF-α. The consequence of these events was the shift of the cytokine profile towards a pro-inflammatory status. These modifications, induced by training performed at an elite level, might negatively affect the growth of female children athletes.  相似文献   
77.
Abstract

Despite a wide international literature on the effect of vocational and general education on school-to-work transition, relatively little is known about the role of having studied specific subjects in explaining inequalities in young people’s labour market outcomes. This paper aims to fill this gap by examining differences in employment chances of young people who left education early, either at the end of compulsory schooling or at the end of secondary school. Using data from the Scottish Longitudinal Study, a large-scale linkage study created using data from administrative and statistical sources, we found little gender differences but strong parental background differences in school leavers’ employment status and type of occupation entered. Social inequalities in labour market outcomes were only partly explained by curriculum choices. Moreover, after controlling for social origin and grades, only history and business for lower-secondary leavers and maths for upper-secondary leavers were associated with a reduction in the chances of being unemployed/inactive.  相似文献   
78.
ABSTRACT

Too often, because of the static nature of schools and the dominant existence of high-stakes testing, professional learning for teachers is determined by administrators or policy and is facilitated by those who are not part of the school community using prepackaged programs. These initiatives run counter to authentic teacher inquiry where teachers enhance their understanding of students and learning and, ideally, develop new teaching practices (Borko, 2004; Cochran-Smith & Lytle, 1999, 2009; Darling-Hammond, 1997). In this article, we focus on how teachers participating in action research begin to position themselves as teacher leaders.  相似文献   
79.
In this article we contrast two distance foreign language programs developed at two European institutions of higher education (the Modern Languages Program at the Open University, UK; and the English Program at the Universitat Oberta de Catalunya, Spain) as instances of two pedagogical models used to address the many challenges posed by teaching languages at a distance. A detailed analysis of both approaches reveals that the pedagogical choices made by both universities are in great measure determined by the historical and cultural contexts in which both institutions are embedded. In addition, we discuss the similarities and differences between the two and draw several conclusions regarding the appropriateness of the two distance universities' general educational, administrative, and technological models for distance language learning.  相似文献   
80.
In 2 studies, we assessed concepts of personal entitlements in more and less hierarchically organized cultures. Study 1 assessed the judgments of 88 adolescent and adult males (mean ages 17-6 and 34-7) from Druze and Jewish communities in Israel. Subjects were presented with conflict situations in which a person in a dominant position (husband, father) objects to the activities of a family member in a subordinate position (wife, daughter, son), and vice versa. Druze subjects attributed more power than Jewish subjects to husbands and fathers over wives and daughters, but concepts of personal entitlements were prominent in both groups. Study 2 assessed the judgements of Druze females (mean ages 12-10, 17-5, and 38-6). Results show that females accept the legitimacy of males' power and personal autonomy, recognize the consequences for those in subordinate positions, and regard the existing social arrangements as unfair. Overall, the findings indicate that social reasoning is heterogeneous in different types of cultures.  相似文献   
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