Glenohumeral joint rotation range of motion in competitive swimmers

Much research has examined shoulder range of motion adaptations in overhead-unilateral athletes. Based on the void examining overhead-bilateral athletes, especially competitive swimmers, we examined shoulder external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion of competitive swimmers. The range of motion of registered competitive swimmers (n = 144, age = 12-61 years) was compared by limb (dominant, non-dominant), sex, and age group (youth, high school, college, masters). Significantly (P < 0.05) greater dominant external rotation was observed for both men and women high school and college swimmers, youth women swimmers, and men masters swimmers compared with the non-dominant limb. The isolated internal rotation (glenohumeral rotation), composite internal rotation (glenohumeral rotation plus scapulothoracic protraction), and total arc of motion (external rotation plus composite internal rotation) of the non-dominant limb was significantly greater than that of the dominant limb by sex and age group. Youth and high school swimmers demonstrated significantly greater composite internal rotation than college and masters swimmers. Youth swimmers displayed significantly greater total arc of motion than all other age groups. These data will aid in the interpretation of shoulder range of motion values in competitive swimmers during preseason screenings, injury evaluations and post-rehabilitation programmes, with the results suggesting that differences exist in bilateral external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion.     

Effect of different swim caps on the assessment of body volume and percentage body fat by air displacement plethysmography

Isothermal air trapped in scalp hair generates an underestimation of body volume when it is measured by air displacement plethysmography. The aim of this study was to examine the effect of wearing different types of swim caps on the measurement of body volume and percentage body fat by air displacement plethysmography. It was hypothesized that wearing a silicone swim cap would more thoroughly compress scalp hair compared with a lycra swim cap, yielding higher estimates of body volume and percent body fat. Thirty female participants aged 25.7 ± 6.4 years were measured in random order when wearing no swim cap, a lycra swim cap or a silicone swim cap. For the no-cap versus lycra cap condition, the mean bias for body volume was -0.579 ± 0.380 litre (limits of agreement: -1.340 to 0.181 litre) and for percent fat -4.9 ± 3.1% fat (limits of agreement: -11.2 to 1.3% fat) (P < 0.05). For the silicone versus lycra condition, the mean bias for body volume was 0.137 ± 0.099 litre (limits of agreement: -0.062 to 0.335 litre) and for percent fat 1.2 ± 0.9% fat (limits of agreement: -0.5 to 2.9% fat) (P < 0.05). In conclusion, attention should be paid to optimal compression of isothermal air trapped in scalp hair when using air displacement plethysmography. The present results suggest that this compression may be more thorough when wearing a silicone swim cap.     

Nutrition for winter sports

Winter sports are played in cold conditions on ice or snow and often at moderate to high altitude. The most important nutritional challenges for winter sport athletes exposed to environmental extremes include increased energy expenditure, accelerated muscle and liver glycogen utilization, exacerbated fluid loss, and increased iron turnover. Winter sports, however, vary greatly regarding their nutritional requirements due to variable physiological and physique characteristics, energy and substrate demands, and environmental training and competition conditions. What most winter sport athletes have in common is a relatively lean physique and high-intensity training periods, thus they require greater energy and nutrient intakes, along with adequate food and fluid before, during, and after training. Event fuelling is most challenging for cross-country skiers competing in long events, ski jumpers aiming to reduce their body weight, and those winter sport athletes incurring repeated qualification rounds and heats. These athletes need to ensure carbohydrate availability throughout competition. Finally, winter sport athletes may benefit from dietary and sport supplements; however, attention should be paid to safety and efficacy if supplementation is considered.     

The impact of different types of physical activity on total and regional bone mineral density in young Brazilian athletes

Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body.     

The effect of patellar taping on EMG activity of vasti muscles during squatting in individuals with patellofemoral pain syndrome

Although patellar taping has been shown to reduce pain in participants with patellofemoral pain syndrome, the mechanisms of pain reduction have not completely been established following its application. The purpose of this study was to evaluate EMG activity of vastus medialis and vastus lateralis following the application of patellar taping during a functional single leg squat. Both vastus medialis obliquus-vastus lateralis onset and vastus medialis obliquus/vastus lateralis amplitude of 18 participants with patellofemoral pain syndrome and 18 healthy participants as controls were measured using an EMG unit. This procedure was performed on the affected knee of participants with patellofemoral pain syndrome, before, during, and after patellar taping during unilateral squatting. The same procedure was also performed on the unaffected knees of both groups. The mean values of vastus medialis obliquus-vastus lateralis onset prior to taping (2.54 ms, s = 4.35) were decreased significantly following an immediate application of tape (-3.22 ms, s = 3.45) and after a prolonged period of taping (-6.00 ms, s = 3.40 s) (P < 0.05). There was also a significant difference between the mean values of vastus medialis obliquus-vastus lateralis onset among controls (-2.03 ms, s = 6.04) and participants with patellofemoral pain syndrome prior to taping (P < 0.05). However, there were no significant difference between the ranked values of vastus medialis obliquus/vastus lateralis amplitude of the affected and unaffected knees of participants with patellofemoral pain syndrome and controls during different conditions of taping (P > 0.05). Decreased values of vastus medialis obliquus-vastus lateralis onset may contribute to patellar realignment and explain the mechanism of pain reduction following patellar taping in participants with patellofemoral pain syndrome.     

Masculinity, moral atmosphere, and moral functioning of high school football players

In order to identify factors associated with on-field moral functioning among student athletes within the unique context of football, we examined masculine gender role conflict, moral atmosphere, and athletic identity. Using structural equation modeling to assess survey data from 204 high school football players, results demonstrated that moral atmosphere (i.e., the influence of coaches and teammates) was significantly associated with participants' process of on-field moral functioning across the levels of judgment, intention, and behavior. Neither masculine gender role conflict nor athletic identity significantly predicted moral functioning, but the results indicated that participants' identification with the athlete role significantly predicted conflict with socialized gender roles. Results suggest that in the aggressive and violent sport of football, coaches can have a direct influence on players' moral functioning process. Coaches can also have an indirect effect by influencing all the players so that a culture of ethical play can be cultivated among teammates and spread from the top down.     

金融资本赋能科技创新建立良性循环机制思考与研究

从科技型中小企业的融资现状和融资需求出发,研究科技金融结合推动科技成果转化机制.聚焦新时期科技成果转化对金、产、研融合提出新要求,基于不同类型的金融资本促进金产研结合、推动科技成果转化进展与成效的研究,以及西方发达国家的有关经验,阐述金、产、研融合良性循环机制的形成原理及现行机制存在的问题,最后提出促进构建金产研良性循环机制的着力点与有关政策建议.     

Using clinical guidelines to assess the potential value of laboratory medicine in clinical decision-making

IntroductionIt is often quoted that 70% of clinical decisions are based on laboratory results, but the evidence to substantiate this claim is lacking. Since clinical guidelines aim to document best-practice decision making for specific disease conditions, inclusion of any laboratory test means that the best available evidence is recommending clinicians use it. Cardiovascular disease (CVD) is the world’s most common cause of mortality, so this study reviewed all CVD guidelines published by five national/international authorities to determine what proportion of them recommended laboratory testing.Materials and methodsFive leading CVD guidelines were examined, namely the European Society of Cardiology (ESC), the UK National Institute for Health and Clinical Excellence (NICE), the American College of Cardiology (ACC), the Australian Heart Foundation (AHF) and the Cardiac Society of Australia and New Zealand (CSANZ).ResultsA total of 101 guidelines were reviewed. Of the 33 individual ESC guidelines relating to CVD, 24/33 made a direct reference to the use of clinical laboratory tests in either diagnosis or follow-up treatment. The same applied to 15/20 of NICE guidelines, 24/32 from the ACC and 15/16 from the AHF/CSANZ. Renal function and blood count testing were the most recommended (39 and 26 times), with lipid, troponin and natriuretic peptide measurement advocated 25, 19 and 19 times respectively.ConclusionsThis study has shown that laboratory testing is advocated by between 73% and 94% of individual CVD guideline recommendations from five national/international authorities. This provides an index to assess the potential value of laboratory medicine to healthcare.     

Bandpass sorting of heterogeneous cells using a single surface acoustic wave transducer pair

Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes.     

Vapor-liquid equilibrium simulation of binary and ternary mixtures of CH4, C2H4 and iso-C4H10

The vapor-liquid equilibrium（VLE） properties for the binary and ternary mixtures of CH4,C2H4 and isoC4H10 are of great importance in the recovery of ethylene from mixture containing CH4 and C2H4 with iso-C4H10 as solvent.Hence,Gibbs ensemble Monte Carlo（GEMC） simulations were used to estimate vapor-liquid equilibrium for the binary and ternary mixtures of CH4,C2H4 and iso-C4H10 with the united atom potential NERD model.The selected simulation conditions are based on the experiment in the literature.The results of this work were shown to be in satisfactory agreement with available experimental data and predictions of Peng-Robinson equation of state.The structure of simulated liquid phase is also characterized by radial distribution function（RDF）,which contributes to further understanding of the VLE curve of these systems.RDF is not sensitive to the pressure and temperature range.With the increase of pressure or the decrease of temperature,the molecules tend to gather together.