Opportunities and constraints: black-white differences in the formation of interracial friendships

In this article, we examine the effects of classroom characteristics on the interracial friendliness of students in desegregated classrooms. We argue that social psychological processes that affect cross-race sociability are set in motion by the classroom climate, the organization of instruction, and the class racial composition. The effects of these variables on the likelihood of cross-race friendships are observed in longitudinal data from 455 students in 16 fourth- through seventh-grade desegregated classrooms. The results show that classroom characteristics associated with "status-leveling" effects operate differently for black and white students. Ability grouping influences the interracial sociability of white students more than that of blacks, while the academic status of peers affects the cross-race friendships of blacks more than of whites. Race differences in the effects of classroom climate on interracial friendships are also observed.     

The body donation program at the Federal University of Health Sciences of Porto Alegre: A successful experience in Brazil

The use of dissection to study human anatomy is the foundation for educational excellence among future health professionals, as it offers an ideal opportunity to learn the body's morphology in three dimensions while also providing students with a more humanistic education. The shortage of bodies for dissection, combined with the Brazilian population's lack of knowledge concerning the possibility of voluntarily donating their own bodies, led to the creation of the Body Donation Programs for Education and Research in Anatomy at the Federal University of Health Sciences of Porto Alegre (UFCSPA). The program is based on three pillars: Informing the general public about the program, donor registration, and donation itself. Since the creation of the donor program in 2008, there has been an increase in both the number of donations made during donor's lifetime and the number of bodies received by the university. There has also been a shift in relation to the origin of these bodies, as before the creation of the program most bodies were unclaimed cadavers, while today most of the bodies are sourced from voluntary donations. The initial results regarding the public's acceptance of the possibility of making body donations have been encouraging, as shown by the annual growth in donor registrations. Consequently, the quality and quantity of the material available for educational purposes have greatly improved. Anat Sci Educ. © 2013 American Association of Anatomists.     

Special Edition on Access and Diversity Guest Editors' Introduction

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.     

A novel μ-fluidic whole blood coagulation assay based on Rayleigh surface-acoustic waves as a point-of-care method to detect anticoagulants

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.     

Leucine metabolites do not attenuate training-induced inflammation in young resistance trained men

ABSTRACT

Leucine metabolites may reduce training-induced inflammation; however, there is scant evidence for this assertion. We conducted a double-blind randomized controlled pragmatic trial where 40 male participants were allocated into 4 groups: α-hydroxyisocaproic acid group ([α-HICA], n = 10, Fat-free mass [FFM] = 62.0 ± 7.1 kg), β-hydroxy-β-methylbutyrate free acid group ([HMB-FA], n = 11, FFM = 62.7 ± 10.5 kg), calcium β-hydroxy-β-methylbutyrate group ([HMB-Ca], n = 9, FFM = 65.6 ± 10.1 kg) or placebo group ([PLA]; n = 10, FFM = 64.2 ± 5.7 kg). An 8-week whole-body resistance training routine (3 training sessions per week) was employed to induce gains in skeletal-muscle thickness. Skeletal muscle thickness (MT), one repetition maximum (1RM), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP) and tumour necrosis factor alpha (TNF-α) were assessed at baseline and at the end of weeks 4 and 8. Time-dependent increases were detected from baseline to week 8 for MT (vastus lateralis: p = 0.009; rectus femoris: p = 0.018), 1RM (back squat: α-HICA, 18.5% ± 18.9%; HMB-FA, 23.2% ± 16%; HMB-Ca, 10.5% ± 13.8%; PLA, 19.7% ± 9% and bench press: α-HICA, 13.8% ± 19.1%; HMB-FA, 15.5% ± 9.3%; HMB-Ca, 10% ± 10.4%; PLA, 14.4 ± 11.3%, both p < 0.001), IL-6, hsCRP (both p < 0.001) and TNF-α (p = 0.045). No differences were found between groups at any time point. No leucine metabolite attenuated inflammation during training. Additionally, backwards elimination regressions showed that no circulating inflammatory marker consistently shared variance with the change in any outcome. Using leucine metabolites to modulate inflammation cannot be recommended from the results obtained herein. Furthermore, increases in inflammatory markers, from training, do not correlate with any outcome variable and are likely the result of training adaptations.     

Physical fitness percentiles for Portuguese children and adolescents aged 10–18 years

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.     

Perceived environmental characteristics and psychosocial factors associated with physical activity levels in adolescents from Northeast Brazil: structural equation modelling analysis

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.     

Impact of compliance with different guidelines on physical activity during pregnancy and perceived barriers to leisure physical activity

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.     

Blood lactate response and critical speed in swimmers aged 10–12 years of different standards

It has previously been shown that measurement of the critical speed is a non-invasive method of estimating the blood lactate response during exercise. However, its validity in children has yet to be demonstrated. The aims of this study were: (1) to verify if the critical speed determined in accordance with the protocol of Wakayoshi et al. is a non-invasive means of estimating the swimming speed equivalent to a blood lactate concentration of 4 mmol·l^-1 in children aged 10-12 years; and (2) to establish whether standard of performance has an effect on its determination. Sixteen swimmers were divided into two groups: beginners and trained. They initially completed a protocol for determination of speed equivalent to a blood lactate concentration of 4 mmol·l^-1. Later, during training sessions, maximum efforts were swum over distances of 50, 100 and 200 m for the calculation of the critical speed. The speeds equivalent to a blood lactate concentration of 4 mmol·l^-1 (beginners = 0.82±0.09 m·s^-1 , trained = 1.19±0.11 m·s^-1; mean±s) were significantly faster than the critical speeds (beginners = 0.78±0.25·s^-1 , trained = 1.08±0.04 m·s^-1) in both groups. There was a high correlation between speed at a blood lactate concentration of 4 mmol·l^-1 and the critical speed for the beginners (r = 0.96, P ? 0.001), but not for the trained group (r = 0.60, P > 0.05). The blood lactate concentration corresponding to the critical speed was 2.7±1.1 and 3.1±0.4 mmol·l^-1 for the beginners and trained group respectively. The percent difference between speed at a blood lactate concentration of 4 mmol·l^-1 and the critical speed was not significantly different between the two groups. At all distances studied, swimming performance was significantly faster in the trained group. Our results suggest that the critical speed underestimates swimming intensity corresponding to a blood lactate concentration of 4 mmol·l^-1 in children aged 10-12 years and that standard of performance does not affect the determination of the critical speed.     

Competition and diversity in higher education: an empirical approach to specialization patterns of Portuguese institutions

The expansion of higher education systems has often been associated with the need for increasing diversification, namely at the program level, based on the pressures to adapt more general programmes to a more diverse student population and multiple regional, social, and economic needs. This paper explores empirically the question of programme diversity by drawing on the Portuguese higher education’ experience, which presented massive expansion during the last decades and significant institutional competition in recent years. The study provides a longitudinal approach and analyzes in detail the evolution of diversification and specialization of the public and private sectors, as well as the university and polytechnic subsectors. The analysis aims at helping to illustrate the relevance of analysing diversity from an empirical point of view and its contribution to our understanding of the complex relationships between competition and diversity in contemporary higher education.