Fluid balance of elite Brazilian youth soccer players during consecutive days of training

In this study we investigated pre-training hydration status, fluid intake, and sweat loss in 20 elite male Brazilian adolescent soccer players (mean?±?s: age 17.2?±?0.5 years; height 1.76?±?0.05?m; body mass 69.9?±?6.0?kg) on three consecutive days of typical training during the qualifying phase of the national soccer league. Urine specific gravity (USG) and body mass changes were evaluated before and after training sessions to estimate hydration status. Players began the days of training mildly hypohydrated (USG?>?1.020) and fluid intake did not match fluid losses. It was warmer on Day 1 (33.1?±?2.4°C and43.4?±?3.2% relative humidity; P?相似文献   

Informationen des Deutschen Olympischen Sportbunds (DOSB)

DOSB-Informationen

Informationen des Deutschen Olympischen Sportbunds (DOSB)     

Three dimensional musculoskeletal modelling of the seated biceps curl resistance training exercise

The aim of this study was to evaluate the benefits and limitations of using three dimensional (3D) musculoskeletal modelling (LifeModeler) in assessing the safety and efficacy of exercising on a seated biceps curl resistance training machine. Three anthropometric cases were studied, representing a 5th percentile female, 50th percentile and 95th percentile male. Results indicated that the LifeModeler default model was not adequate to solve the forward dynamics simulations. Therefore adjustments had to be made to the default model to successfully complete the forward dynamics simulations. The software was able to sufficiently highlight the shortcomings of the biceps curl machine's engineered adjustability in relation to the anthropometric dimensions of the studied cases, as the 5th percentile female could not be accommodated suitably on the machine. High lumbar spine anterior/posterior shear forces for all anthropometric cases and maximum muscle tensions for the female and 50th percentile male indicate that the seated biceps curl exercise may pose risks for injuries. To conclude, it appears that 3D musculoskeletal modelling can be used to evaluate resistance training equipment such as the seated biceps curl machine. However the limitations as indicated by this study must be taken into consideration, especially when using the default LifeModeler model.     

毒品及艾滋病致孤儿童集中教育救助实践探索——以边疆少数民族地区某小学为例

云南省某边疆少数民族地区,项目县将部分义务教育阶段的毒品及艾滋病致孤学生全免费集中于县直属某小学的各班级,通过社会各界捐助和学校经费倾斜,解决他们的学习、生活及医疗等问题。实施在校期间由学校集中救助教养、寒暑假期由乡镇政府接回交给原代理监护人看管的方式,历经四年多的实践探索,初步形成学校集中救助毒品及艾滋病致孤儿童的特色教育救助模式。     

Predicting homework motivation and homework effort in six school subjects: The role of person and family characteristics,classroom factors,and school track

This study examines the determinants of homework motivation and homework effort in six school subjects at three levels: student level, classroom level, and school level. We hypothesized that several factors—including stable personality characteristics such as gender and conscientiousness, students' domain-specific homework motivation, and characteristics of homework assignments—have concomitant effects on student homework effort. The sample consisted of 511 students in Grades 8 and 9. Across all six school subjects, multilevel modelling showed that students' homework motivation and homework effort varied primarily as a function of their shared perceptions of homework quality and control (classroom level) and of their conscientiousness, individual perception of homework quality, and expectancy and value beliefs (student level). Domain-specific patterns were found for student gender in line with gender stereotypes. Cognitive ability, family background, and parental homework help or control were only loosely associated with homework motivation and homework effort.     

Quantum cryptography beyond key exchange

This chapter describes the applicability of quantum cryptography beyond key exchange. The section is devided into two parts: one describing applications of quantum cryptography different from key exchange and the other considering countermeasures to additional threats like coercibility or traffic analysis. Every section ends with a short summary or an appraisal in boldface and in the conclusions all topics of this section are briefly outlined and in an outlook we give a personal statement about the relevance of quantum cryptographic pro tocols and promising future directions of research.