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981.
Education is an indispensable element for the development of society. In Latin America, the point of origin of most of the undocumented immigrants to the United States, equal opportunity in access to education and educational achievement is still pending. The study presented here focuses on the analysis of the expectations of female migrants via Mexico’s northern border, focusing attention on educational attainment as an important aspect of the “American Dream” of the migrant women interviewed and their dependents.  相似文献   
982.
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   
983.
The purpose of this study was to assess the reproducibility of body composition measurements by dual-energy X-ray absorptiometry (DXA) in 12 elite male wheelchair basketball players (age 31 ± 7 years, BMI 21 ± 2 kg/m2 and onset of disability 25 ± 9 years). Two whole body scans were performed on each participant in the supine position on the same day, using Lunar Prodigy Advance DXA (GE Lunar, Madison, WI, USA). Participants dismounted from the scanning table and were repositioned in-between the first and second scan. Whole body coefficient of variation (CV) values for bone mineral content (BMC), fat mass (FM) and soft tissue lean mass (LTM) were all <2.0%. With the exclusion of arm FM (CV = 7.8%), CV values ranged from 0.1 to 3.7% for all total body and segmental measurements of BMC, FM and LTM. The least significant change that can be attributed to the effect of treatment intervention in an individual is 1.0 kg, 1.1 kg, 0.12 kg for FM, LTM, and BMC, respectively. This information can be used to determine meaningful changes in body composition when assessed using the same methods longitudinally. Whilst there may be challenges in the correct positioning of an individual with disability that can introduce greater measurement error, DXA is a highly reproducible technique in the estimation of total and regional body composition of elite wheelchair basketball athletes.  相似文献   
984.
This paper aims to analyze gender verifications in sport from a socio-historical approach. These medical controls intended to keep men from competing in women's international competitions. Some female athletes are put through a masculinization trial, because of morphologies and performances judged as too masculine. Facing these athletes who disrupt the representation of a binary construction between the male sex and the female sex, sports institutions attempt to maintain a sexual bi-categorization. More precisely, this paper will present the ‘symbolic’ suppression of tests since 2000. Thereafter, authorities only rely on an aesthetic and visual assessment of female bodies and no longer use tests in a systematic and obligatory fashion. This reveals the moving boundary subjectively plotted between the masculine and the feminine, which become all the more blurred when the ‘race and class markers’ interfere with the ‘sex markers’.  相似文献   
985.
Electrosprays are a powerful technique to generate charged micro/nanodroplets. In the last century, the technique has been extensively studied, developed, and recognized with a shared Nobel price in Chemistry in 2002 for its wide spread application in mass spectrometry. However, nowadays techniques based on microfluidic devices are competing to be the next generation in atomization techniques. Therefore, an interesting development would be to integrate the electrospray technique into a microfluidic liquid-liquid device. Several works in the literature have attempted to build a microfluidic electrospray with disputable results. The main problem for its integration is the lack of knowledge of the working parameters of the liquid-liquid electrospray. The “submerged electrosprays” share similar properties as their counterparts in air. However, in the microfluidic generation of micro/nanodroplets, the liquid-liquid interfaces are normally stabilized with surface active agents, which might have critical effects on the electrospray behavior. In this work, we review the main properties of the submerged electrosprays in liquid baths with no surfactant, and we methodically study the behavior of the system for increasing surfactant concentrations. The different regimes found are then analyzed and compared with both classical and more recent experimental, theoretical and numerical studies. A very rich phenomenology is found when the surface tension is allowed to vary in the system. More concretely, the lower states of electrification achieved with the reduced surface tension regimes might be of interest in biological or biomedical applications in which excessive electrification can be hazardous for the encapsulated entities.  相似文献   
986.
The main objective of this research was to review the characteristics of portfolios and their outcomes for teaching professionalism to undergraduate medical students. A systematic review on the use of portfolios in teaching professionalism to medical students identified 1257 papers. Of these, 11 articles met all inclusion criteria. According to the papers, the use of portfolios for teaching professionalism shows versatility, supports learning strategies and has the potential to be used in different contexts, including for formative and summative purposes. The weaknesses were based on the artificiality of the reflections, deficient instructions, time-consuming processes and preference among students for other teaching methods. Students complained about feeling that the reflection was ‘forced’, and they tended to write based on social conventions rather than reveal their true thoughts. Reflection is a powerful component of the portfolio, but the method by which it is taught could easily ruin its potential to boost professionalism. Requiring reflection did not ensure its achievement; increased understanding by students regarding how and why they were doing it, the clarity of assessment methods and constructive feedback might strengthen the potential for success. A framework was designed to support faculty members in developing and applying portfolios with a clear and broad view of this teaching strategy.  相似文献   
987.
ABSTRACT

We assessed the intraocular pressure (IOP) behaviour during a 1-minute period of isometric physical effort and the immediate 1-minute of recovery in the mid-thigh clean pull and squat exercises at three different intensities. Twenty physically active individuals performed the isometric mid-thigh clean pull and squat exercises at three intensities (0% [low-intensity], 25% [medium-intensity] and 50% [high-intensity] of the maximum isometric force). IOP was semi-continuously measured by rebound tonometry. There was a statistically significant effect of exercise intensity on IOP (p < 0.001, ?p² = 0.416), observing that IOP increments were positively associated with exercise intensity. The mid-thigh clean pull and squat exercises did not demonstrate differences (p = 0.510), and also, no differences were observed between men and women (p = 0.683). The IOP changes during the isometric physical effort showed a positive linear behaviour in all conditions (r = 0.70 to 0.96). IOP returned to baseline levels after 8 seconds of recovery. Our data showed a progressive and instantaneous IOP increment during isometric exercise, which was positively associated with exercise intensity. IOP changes were independent on the type of exercise and participant´s sex. After exercise, IOP rapidly (≈ 8 seconds) returned to baseline levels.  相似文献   
988.
The Spanish Service was established in June 1939, two months after the end of the civil war in Spain and shortly before the start of the Second World War. Its implementation was strongly affected by these conflicts in the context of new international relations. Therefore, this study of the Spanish Service during 1939–1945 allows not only a better understanding of the communicational strategies developed by the BBC, but also of the complex Anglo-Spanish relations and the important role played by the Spanish-language broadcasts therein. The study is mainly based on archival documents from the National Archives in London and memoirs.  相似文献   
989.
990.
ABSTRACT

Higher education (HE) research often draws on a range of qualitative research approaches. However, some methods developed in other fields are underutilised in HE research, even though they could be of great use for answering particular kinds of research questions, or for involving students more actively in the research process. In this article, we draw on a study that piloted different methodological approaches to explore students’ conceptions of good teaching and effective learning at university. The participants in our study included 33 high achieving international, Māori, Pacific Island, and (other) local students enrolled in Humanities subjects. Our study used photovoice as a visual data collection approach in conjunction with more traditional methods of data collection: open-ended focus group questions and critical incident technique. In this article, we review the photovoice literature, which is mostly from outside HE. Then, we describe our study, discussing the students’ responses to photovoice, and the different kinds of data it elicited. We note that, while most students expressed appreciation of the photovoice approach, some also found it restrictive and challenging in some respects. We conclude, photovoice offers a useful methodological addition to HE research, while noting, as with all data collection approaches, researchers need to be mindful of its limitations.  相似文献   
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