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1.
The present investigation was carried out to examine the incidence and pattern of injuries in adolescent multisport athletes from youth sports academy. Injury data were prospectively collected from 166 athletes during the seasons from 2009 to 2014. A total of 643 injuries were identified, 559 (87.0%) were time-loss injuries. The overall injury incidence was 5.5 (95% confidence interval CI: 5.1–6.0), the incidence of time-loss injuries was 4.8 (95% CI: 4.4–5.2), the incidence of growth conditions was 1.2 (95% CI: 1.0–1.4) and incidence of serious injuries was 0.6 (95% CI: 0.5–0.8) per 1000?h of exposure. The prevalence of overuse injuries was 50.3%. Growth conditions represented 20.0%. Most of the injuries (67.0%) involved the lower extremities, and both foot and ankle were the most predominant injured body parts (22.0%). Knee injuries were mostly from overuse (50 vs. 23, p?=?.02), whereas foot and ankle injuries resulted from an acute mechanism (94 vs. 31, p?<?.0001). Minor and moderate injuries accounted for 87.0%. Muscle, tendon and osteochondrosis injuries accounted for 52.0% of all injuries. Comparing groups, squash sport was having the highest injury incidence (8.5 injuries per athlete). Higher exposure was associated with greater overuse relative risk (RR?=?1.03, 95% CI: 1.01–1.014, p?<?.001). In conclusion, the results of this study identified a high incidence of injuries in this youth sports population. Striking was the prevalence of overuse injuries of 50%, which suggests the need for injury prevention protocols for adolescent highly trained athletes.  相似文献   
2.
Domesticated buffaloes have been integral to rice-paddy agro-ecosystems for millennia, yet relatively little is known about the buffalo genomics. Here, we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals (132 swamp buffaloes and 98 river buffaloes) sampled from across Asia and Europe. Beyond the many actionable insights that our study revealed about the domestication, basic physiology and breeding of buffalo, we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior, digestion metabolism, strengths and milk production.  相似文献   
3.
Issues regarding scientific explanation have been of interest to philosophers from Pre-Socratic times. The notion of scientific explanation is of interest not only to philosophers, but also to science educators as is clearly evident in the emphasis given to K-12 students' construction of explanations in current national science education reform efforts. Nonetheless, there is a dearth of research on conceptualizing explanation in science education. Using a philosophically guided framework—the Nature of Scientific Explanation (NOSE) framework—the study aims to elucidate and compare college freshmen science students', secondary science teachers', and practicing scientists' scientific explanations and their views of scientific explanations. In particular, this study aims to: (1) analyze students', teachers', and scientists' scientific explanations; (2) explore the nuances about how freshman students, science teachers, and practicing scientists construct explanations; and (3) elucidate the criteria that participants use in analyzing scientific explanations. In two separate interviews, participants first constructed explanations of everyday scientific phenomena and then provided feedback on the explanations constructed by other participants. Major findings showed that, when analyzed using NOSE framework, participant scientists did significantly “better” than teachers and students. Our analysis revealed that scientists, teachers, and students share a lot of similarities in how they construct their explanations in science. However, they differ in some key dimensions. The present study highlighted the need articulated by many researchers in science education to understand additional aspects specific to scientific explanation. The present findings provide an initial analytical framework for examining students' and science teachers' scientific explanations.  相似文献   
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Passive particle focusing based on inertial microfluidics was recently introduced as a high-throughput alternative to active focusing methods that require an external force field to manipulate particles. In inertial microfluidics, dominant inertial forces cause particles to move across streamlines and occupy equilibrium positions along the faces of walls in flows through straight micro channels. In this study, we systematically analyzed the addition of secondary Dean forces by introducing curvature and show how randomly distributed particles entering a simple u-shaped curved channel are focused to a fixed lateral position exiting the curvature. We found the lateral particle focusing position to be fixed and largely independent of radius of curvature and whether particles entering the curvature are pre-focused (at equilibrium) or randomly distributed. Unlike focusing in straight channels, where focusing typically is limited to channel cross-sections in the range of particle size to create single focusing point, we report here particle focusing in a large cross-section area (channel aspect ratio 1:10). Furthermore, we describe a simple u-shaped curved channel, with single inlet and four outlets, for filtration applications. We demonstrate continuous focusing and filtration of 10 μm particles (with >90% filtration efficiency) from a suspension mixture at throughputs several orders of magnitude higher than flow through straight channels (volume flow rate of 4.25 ml/min). Finally, as an example of high throughput cell processing application, white blood cells were continuously processed with a filtration efficiency of 78% with maintained high viability. We expect the study will aid in the fundamental understanding of flow through curved channels and open the door for the development of a whole set of bio-analytical applications.  相似文献   
6.
Are mother–child conflict discussions shaped by time-varying, reciprocal influences, even after accounting for stable contributions from each individual? Mothers were filmed discussing a conflict for 5 min, separately with their younger (ages 5–9, N = 217) and older (ages 7–13, N = 220) children. Each person’s conflict constructiveness was coded in 20-s intervals and data were analyzed using dynamic structural equation modeling, which separates individual and influence effects. Children influenced their mothers’ behavior under certain conditions, with evidence for developmental differences in the magnitude and direction of influence, whereas mothers did not influence their children under any circumstance. Results are discussed in the context of child effects on parent behavior and changes in parenting across middle childhood.  相似文献   
7.
Sigma is a metric that quantifies the performance of a process as a rate of Defects-Per-Million opportunities. In clinical laboratories, sigma metric analysis is used to assess the performance of laboratory process system. Sigma metric is also used as a quality management strategy for a laboratory process to improve the quality by addressing the errors after identification. The aim of this study is to evaluate the errors in quality control of analytical phase of laboratory system by sigma metric. For this purpose sigma metric analysis was done for analytes using the internal and external quality control as quality indicators. Results of sigma metric analysis were used to identify the gaps and need for modification in the strategy of laboratory quality control procedure. Sigma metric was calculated for quality control program of ten clinical chemistry analytes including glucose, chloride, cholesterol, triglyceride, HDL, albumin, direct bilirubin, total bilirubin, protein and creatinine, at two control levels. To calculate the sigma metric imprecision and bias was calculated with internal and external quality control data, respectively. The minimum acceptable performance was considered as 3 sigma. Westgard sigma rules were applied to customize the quality control procedure. Sigma level was found acceptable (≥3) for glucose (L2), cholesterol, triglyceride, HDL, direct bilirubin and creatinine at both levels of control. For rest of the analytes sigma metric was found <3. The lowest value for sigma was found for chloride (1.1) at L2. The highest value of sigma was found for creatinine (10.1) at L3. HDL was found with the highest sigma values at both control levels (8.8 and 8.0 at L2 and L3, respectively). We conclude that analytes with the sigma value <3 are required strict monitoring and modification in quality control procedure. In this study application of sigma rules provided us the practical solution for improved and focused design of QC procedure.  相似文献   
8.
The Urban Review - This article draws from the authors’ inquiry into their experiences in an intergenerational research project—an afterschool youth participatory action research...  相似文献   
9.
The purpose was to assess sleep patterns, quantity and quality in adolescent (16.2?±?1.2 yr) Middle Eastern academy soccer players (n?=?20) and the influence of an intermission upon these characteristics. On a 17-day training camp (located one time zone west of home) including three discrete matches, sleep was assessed pre- (PRE) and post-match (POST) via wrist actigraphy. Retrospective actigraphy analysis identified sleep characteristics, including if players experienced a sleep intermission (YES) or not (NO) proximal to dawn, and bedtime (hh:mm), get-up time (hh:mm), time in bed (h), sleep duration (h) and sleep efficiency (%). Within YES two bouts were identified (BOUT1 and BOUT2). No differences were seen between PRE and POST, nor between BOUT1 and BOUT2 (p?>?.05). Overall players did not meet National Sleep Foundation (NSF) guidelines (7:04?±?1:16?h vs. recommended 8–10?h for 14–17 yr). Sleep duration was significantly reduced (~ ?13% or ?1:06) in YES compared to NO (6:33?±?1:05 vs. 7:29?±?1:17, p?<?.01). Despite players in YES waking earlier due to an intermission, they did not compensate for this with a later wake time, rising significantly earlier compared to NO (09:40?±?00:38 vs. 10:13?±?00:40, p?<?.05). These players on average do not obtain sufficient sleep durations relative to NSF guidelines, with decrements increased by an intermission proximal to dawn. High inter- and intra-individual variance in the players sleep characteristics indicates the need for individualized sleep education strategies and interventions to promote appropriate sleep.  相似文献   
10.
This study is a comparative analysis of the environmental philosophies of college undergraduates enrolled in a Midwestern university. Two courses were used for the research, one from a recreation management curriculum and the other from environmental studies. The study utilized a survey instrument called the Environmental Action and Philosophy Matrix to determine the extent to which students’ environmental attitudes are based on scientific or religious rationale, as well as anthropocentric or biocentric perspectives. Findings show students to possess scientific underpinnings for their viewpoints, regardless of anthropocentric or biocentric tendencies. In addition, the environmental studies students displayed more biocentric attitudes than the recreation management students.  相似文献   
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