Fatigue increases ankle sprain risk in badminton players: A biomechanical study     

Alexis Herbaut  Julien Delannoy 《Journal of sports sciences》2020,38(13):1560-1565

ABSTRACT

Ankle sprains are the most common injury in regular badminton players and usually occur at the end of a match or training. The purpose of the present study was to examine the influence of fatigue produced by badminton practice on the lower limb biomechanics of badminton players. It was hypothesized that fatigue induces ankle kinematic and lower leg muscle activity changes which may increase the risk of ankle sprain. Ankle kinematics, ankle kinetics and muscles activities of 17 regular badminton players were recorded during lateral jumps before and after an intense badminton practice session. Post-fatigue, ankle inversion at foot strike and peak ankle inversion increased (+2.6°, p = 0.003 and +2.5°, p = 0.005, respectively). EMG pre-activation within 100 ms before foot landing significantly decreased after fatigue for soleus (?23.4%, p = 0.031), gastrocnemius lateralis (?12.2%, p = 0.035), gastrocnemius medialis (?23.3%, p = 0.047) and peroneus brevis (?17.4%, p = 0.036). These results demonstrate impaired biomechanics of badminton players when fatigue increases, which may cause a greater risk of experiencing an ankle sprain injury.  相似文献   

Field-study science classrooms as positive and enjoyable learning environments     

Julien?M.?Zaragoza  Barry?J.?FraserEmail author 《Learning Environments Research》2017,20(1):1-20

We investigated differences between field-study classrooms and traditional science classrooms in terms of the learning environment and students’ attitudes to science, as well as the differential effectiveness of field-study classrooms for students differing in sex and English proficiency. A modified version of selected scales from the What Is Happening In this Class? questionnaire was used to assess the learning environment, whereas students’ attitudes were assessed with a shortened version of a scale from the Test of Science Related Attitudes. A sample of 765 grade 5 students from 17 schools responded to the learning environment and attitude scales in terms of both their traditional science classrooms and classrooms at a field-study centre in Florida. Large effect sizes supported the effectiveness of the field-studies classroom in terms of both the learning environment and student attitudes. Relative to the home school science class, the field-study class was considerably more effective for students with limited English proficiency than for native English speakers.  相似文献   

Relationship between abdominal adiposity,cardiovascular fitness,and biomarkers of cardiovascular risk in British adolescents     

Moira S. Lewitt  Julien S. Baker 《运动与健康科学(英文)》2020,9(6):634-644

BackgroundPuberty is a critical time in the development of overweight and obesity. The aim of this study was to examine relationships between measures of adiposity, cardiovascular fitness, and biomarkers of cardiovascular disease risk in adolescents.MethodsIn a cross-sectional study design, 129 girls and 95 boys aged 12.9–14.4 years at various stages of puberty were included, along with their mothers (n = 217) and fathers (n = 207). Anthropometric assessments of adiposity were made, along with cardiovascular physical fitness, using the 20-m shuttle run test, and biomarkers associated with cardiovascular risk, including glucose, insulin, triglyceride, fibrinogen, and C-reactive protein (CRP) concentrations.ResultsWaist-to-height ratio values were similar in boys and girls and correlated positively with diastolic blood pressure, insulin, triglyceride, fibrinogen, and CRP concentrations, and inversely with cardiovascular fitness scores. Skinfold thickness measurements were higher in girls. High-molecular-weight adiponectin concentrations were lower in boys than girls, particularly in late puberty, and CRP levels were higher. Cardiovascular fitness, maternal body mass index (BMI), and paternal BMI contributed independently to the variance in waist measurements in girls and boys. Gender, triceps skinfold thickness, and weight-to-height ratio, but not parental BMI, contributed independently to the variance in cardiovascular fitness.ConclusionThere is a relationship between measures of adolescent adiposity and parental weight that involves factors other than cardiovascular fitness. Adolescent boys have relatively more abdominal fat than girls and a tendency to have a proinflammatory profile of biomarkers. These observations suggest that family and social environmental interventions are best undertaken earlier in childhood, particularly among boys.  相似文献   

Building-stones—elements of strength in their constitution and structure     

Alexis A. Julien 《Journal of The Franklin Institute》1899,147(6):430-442

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Remarks on the structural conditions of iron     

T.R.V. Fuchs 《Journal of The Franklin Institute》1838,26(6):410-412

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Enriching Curriculum for All Students. Renzulli,J. S., & Reis,S. M. (2008)     

Howard Michael Fuchs 《Roeper Review》2013,35(3):209-210

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Extending Responsiveness to Intervention to Mathematics at First and Third Grades     

Lynn S. Fuchs  Douglas Fuchs  Kurstin N. Hollenbeck 《Learning disabilities research & practice》2007,22(1):13-24

Responsiveness to intervention (RTI) is an innovative approach to the identification of learning disabilities (LD). The central assumption is that RTI can differentiate between two explanations for low achievement: poor instruction versus disability. If the child responds poorly to validated instruction, then the assessment eliminates instructional quality as a viable explanation for poor academic growth and instead provides evidence of a disability. For children who do respond nicely, RTI serves a critical prevention function. Most of RTI research has been focused on early reading. In this article, we describe two ongoing programs of research on RTI in the area of mathematics: one on a comprehensive mathematics curriculum at first grade and the other focused on word problems at third grade. For each research program, we describe the sample, explain how students are identified as at risk for mathematics disability, provide an overview of the interventions to which responsiveness is gauged, and describe some results to date.  相似文献   

Two-stage screening for math problem-solving difficulty using dynamic assessment of algebraic learning     

Fuchs LS  Compton DL  Fuchs D  Hollenbeck KN  Hamlett CL  Seethaler PM 《Journal of learning disabilities》2011,44(4):372-380

The purpose of this study was to explore the utility of a dynamic assessment (DA) of algebraic learning in predicting third graders' development of mathematics word-problem difficulty. In the fall, 122 third-grade students were assessed on a test of math word-problem skill and DA of algebraic learning. In the spring, they were assessed on word-problem performance. Logistic regression was conducted to contrast two models. One relied exclusively on the fall test of math word-problem skill to predict word-problem difficulty on the spring outcome (less than the 25th percentile). The second model relied on a combination of the fall test of math word-problem skill and the fall DA to predict the same outcome. Holding sensitivity at 87.5%, the universal screener alone resulted in a high proportion of false positives, which was practically reduced when DA was included in the prediction model. Findings are discussed in terms of a two-stage process for screening students within a responsiveness-to-intervention prevention model.  相似文献   

On the importance of a cognitive processing perspective: an introduction     

Fuchs D  Hale JB  Kearns DM 《Journal of learning disabilities》2011,44(2):99-104

Children with learning problems require early intervention. If it is evidence based and implemented with integrity and intensity, it will accelerate the academic progress of many students. This is the hope and expectation of the many supporters of responsiveness-to-intervention (RTI). A minority of children, however, will not respond sufficiently to such intervention because of learning disorders like specific learning disabilities (SLD). Some RTI models do not include research-backed methods to identify these children, nor do RTI practitioners often produce the data necessary to develop individualized instruction for them. The authors suggest practitioners go beyond typical RTI assessment data documenting responsiveness/ unresponsiveness to conduct comprehensive evaluations of these most difficult-to-teach students and to include in their evaluations carefully chosen cognitive measures. This special issue presents the work of teams of researchers, which suggests that cognitive and neuropsychological assessments can provide information to further understand SLD, which in turn can guide development of promising interventions.  相似文献   

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

Gergely Simon  Caroline Busch  Marco A. B. Andrade  Julien Reboud  Jonathan M. Cooper  Marc P. Y. Desmulliez  Mathis O. Riehle  Anne L. Bernassau 《Biomicrofluidics》2021,15(1)

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.  相似文献