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11.
To assess the effectiveness of breast support previous studies monitored breast kinematics and kinetics, subjective feedback, muscle activity (EMG), ground reaction forces (GRFs) and physiological measures in isolation. Comparing these variables within one study will establish the key performance variables that distinguish between breast supports during activities such as running. This study investigates the effects of changes in breast support on biomechanical, physiological and subjective measures during running. Ten females (34D) ran for 10 min in high and low breast supports, and for 2 min bare breasted (2.8 m·s?1). Breast and body kinematics, EMG, expired air and heart rate were recorded. GRFs were recorded during 10 m overground runs (2.8 m·s?1) and subjective feedback obtained after each condition. Of the 62 variables measured, 22 kinematic and subjective variables were influenced by changes in breast support. Willingness to exercise, time lag and superio-inferior breast velocity were most affected. GRFs, EMG and physiological variables were unaffected by breast support changes during running. Breast displacement reduction, although previously advocated, was not the most sensitive variable to breast support changes during running. Instead breast support products should be assessed using a battery of performance indicators, including the key kinematic and subjective variables identified here.  相似文献   
12.
Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation.  相似文献   
13.
Coaches and athletes have been increasingly inundated with power related ‘truths’ about their bodies, health and performance as they construct their subjectivities. Over the last couple of decades in New Zealand, schools have initiated elite athlete programmes (EAPs) for a select few students based primarily on their athletic ability and fitness levels. Drawing on Gore's techniques of power, my study investigated how healthism and the cult of the body discourses were (re)produced, negotiated and resisted by coaches and elite athletes and how body pedagogies defined and shaped bodies in two high school EAPs. My analysis suggested that ‘toned and fit’ bodies signified responsible athletes compared to ‘fat’ bodies and that elite athletes disciplined their bodies to overcome pain to remain productive. In both EAPs, power circulated at the micro-level of pedagogical practice to normalise and monitor the athletes’ diet, body weight and shape, and reinforced tensions between prudentialism and hedonism.  相似文献   
14.
The purpose of this study was to assess receptivity to peer teaching and peer learning about the safe and appropriate use of medications among communitydwelling older adults. The sample was predominately White (88.5%), female (75.9%) older adults with an average age of 80.2 ( - 9.1) years. On average, the participants perceived their health status as good (2.8 - 0.6). In addition, participants reported using an average number of 4.4 ( - 3.3) prescribed medications. The majority (75%) of participants also reported no problems with their medications. With respect to receptivity to peer teaching and peer learning, the participants, on average, were neutral to peer teaching (6.0 - 2.4), but were somewhat receptive to peer learning (6.7 - 2.2). The number of prescribed medications that a participant reported taking and the age of a participant were identified as significant predictors of receptivity to peer teaching and accounted for 14.5% of the total variance ( F = 5.84, df = 2, p = 0.005). For receptivity to peer learning, the number of prescribed medications also was a significant predictor ( F = 7.50, df = 1, p = 0.008). This study provides the initial step to identifying community-dwelling older adults who would be receptive to peer teaching and peer learning about the safe and appropriate use of medications.  相似文献   
15.
Football is central to Brazilian society, its way of imagining itself and its position in the world. Existing accounts of the origins of football in Brazil in the late nineteenth- and early twentieth-centuries tend towards mono-causal explanations, highlighting the role of British pioneers and Brazilian enthusiasm for the game. This article argues for a multi-causal explanation, using a mixed methodology of archival research in Brazil and the UK, combined with spatial analysis through the development of GIS maps. Building upon the existing interpretations, it shows how important the historical contexts of dynamics of urban expansion and transport infrastructure development – both with considerable British influence – were to the establishment of football as Brazil's national sport.  相似文献   
16.
Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D3 supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D3 supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D3 group and decreased by 43% in the placebo group (both = 0.001). The percentage change of plasma cathelicidin concentration in the vitamin D3 group was higher than in the placebo group (= 0.025). Only in the vitamin D3 group, the saliva SIgA and cathelicidin secretion rates increased over time (both = 0.03). A daily 5000 IU vitamin D3 supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period, which could improve resistance to respiratory infections.  相似文献   
17.
In this article, the authors borrow from anti-oppressive education theory for its potential to disrupt how students visually conceive sporting bodies and to problematize the teaching and learning of these bodies within undergraduate physical education (PE) programs. Fourteen photo stories produced by students enrolled in PE programs at two universities were analysed using a semiotic approach to excavate the emergent themes of sporting bodies from the narratives. Relying on Kumashiro's anti-oppressive educational theoretical framework, the authors found that most of stories reified discursive practices that (re)produce gender oppression in sport. Despite these findings, the authors also discovered anti-oppressive pedagogies are useful for teaching against the body oppressions conveyed in the photo stories. How anti-oppressive education informs other areas of PE should be examined in the future.  相似文献   
18.
Purpose: The purpose of this study was to investigate whether loads carried in a backpack, with a load mass ranging from 0 to 20?kg, causes respiratory muscle fatigue. Methods: Eight males performed four randomised load carriage (LC) trials comprising 60?min walking at 6.5?km?h?1 wearing a backpack of either 0 (LC0), 10 (LC10), 15 (LC15) or 20?kg (LC20). Inspiratory (PImax) and expiratory (PEmax) mouth pressures were assessed prior to and immediately following each trial. Pulmonary gas exchange, heart rate (HR), blood lactate and glucose concentration and perceptual responses were recorded during the first and final 60?s of each trial. Results: Group mean PImax and PEmax were unchanged following 60-min load carriage in all conditions (p?>?.05). There was an increase over time in pulmonary gas exchange, HR and perceptions of effort relative to baseline measures during each trial (p?p?>?.05). Conclusions: These findings indicate that sub-maximal walking with no load or carrying 10, 15 or 20?kg in a backpack for up to 60?min does not cause respiratory muscle fatigue despite causing an increase in physiological, metabolic and perceptual parameters.  相似文献   
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The paper describes the design and use of a studio system which arose out of the need to give demonstrations of experimental procedures to practical classes of up to 150 students. Since the requirements could be specified in some detail it was possible to use novel methods of working which turned out to be very efficient and economical.  相似文献   
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