The location of the tibial accelerometer does influence impact acceleration parameters during running     

Angel Gabriel Lucas-Cuevas  Alberto Encarnación-Martínez  Andrés Camacho-García  Salvador Llana-Belloch  Pedro Pérez-Soriano 《Journal of sports sciences》2017,35(17):1734-1738

Tibial accelerations have been associated with a number of running injuries. However, studies attaching the tibial accelerometer on the proximal section are as numerous as those attaching the accelerometer on the distal section. This study aimed to investigate whether accelerometer location influences acceleration parameters commonly reported in running literature. To fulfil this purpose, 30 athletes ran at 2.22, 2.78 and 3.33 m · s^–1 with three accelerometers attached with double-sided tape and tightened to the participants’ tolerance on the forehead, the proximal section of the tibia and the distal section of the tibia. Time-domain (peak acceleration, shock attenuation) and frequency-domain parameters (peak frequency, peak power, signal magnitude and shock attenuation in both the low and high frequency ranges) were calculated for each of the tibial locations. The distal accelerometer registered greater tibial acceleration peak and shock attenuation compared to the proximal accelerometer. With respect to the frequency-domain analysis, the distal accelerometer provided greater values of all the low-frequency parameters, whereas no difference was observed for the high-frequency parameters. These findings suggest that the location of the tibial accelerometer does influence the acceleration signal parameters, and thus, researchers should carefully consider the location they choose to place the accelerometer so that equivalent comparisons across studies can be made.  相似文献   

Mexican-Origin Youth's Cultural Orientations and Adjustment: Changes From Early to Late Adolescence     

KA Updegraff  AJ Umaña-Taylor  SM McHale  LA Wheeler  NJ Perez-Brena 《Child development》2012,83(5):1655-1671

Drawing from developmental and cultural adaptation perspectives and using a longitudinal design, this study examined: (a) mean‐level changes in Mexican‐origin adolescents’ cultural orientations and adjustment from early to late adolescence and (b) bidirectional associations between cultural orientations and adjustment using a cross‐lag panel model. Participants included 246 Mexican‐origin, predominantly immigrant families that participated in home interviews and a series of nightly phone calls when target adolescents were 12 and 18 years of age. Girls exhibited more pronounced declines in traditional gender role attitudes than did boys, and all youth declined in familism values, time spent with family, and involvement in Mexican culture. Bidirectional relations between cultural orientations and adjustment emerged, and some associations were moderated by adolescent nativity and gender.  相似文献   

Designing a flashcard with knowledge pills for learning to solve chemistry exercises     

Angeles Cancela  Angel Sanchez 《European Journal of Engineering Education》2012,37(4):366-374

Nowadays, universities tend to promote more learner-centred learning, creating a more interactive and motivational environment for students and teachers. This paper describes an expanded framework to help chemical educators to construct a quiz for solution of chemical exercises in their courses. The novelty of this contribution is that the proposed tool combines a flashcards-based method with knowledge pills. The framework has three levels: definition of problem for a teacher; the quiz; use of the quiz for the student. The tool could provide predefined or automatically generated exercises of chemicals. Students could practise where and whenever they like via the Internet. Theirs answers would be registered automatically by the tool and if the students have doubts about any of the questions, they can see a knowledge pill with a teacher explanation about the solution of the exercise. Moreover, they would be able to check their scores from the tests. Once the flashcards were designed and produced, the opinions of other lecturers and students about them were considered. Both groups considered that the tool could be useful to improve the students’ learning process. For future work, this design will be used with the students and its effectiveness will be analysed.  相似文献   

How clicker use facilitates existing pedagogical practices in higher education: data from interdisciplinary research on student response systems     

Angel Hoekstra  Stefanie Mollborn 《Learning, Media and Technology》2012,37(3):303-320

This article identifies how clicker use can support or augment existing principles of good teaching across different disciplines in higher education. While many of these principles will be familiar to instructors, the link between student response system (SRS) use and existing pedagogical methods is still often unclear, even for scholars who are well read in the literature. Functioning as a resource for both novices and instructors who have already incorporated clickers into their courses, this article synthesizes existing literature and offers empirical data from five courses in three disciplines to show how SRSs can be used to support contemporary pedagogical goals. The authors discuss five exemplary practices, providing sample clicker questions along the way, to show how clickers can be used to facilitate active learning in large courses.  相似文献   

More than science: family learning in a Mexican science museum     

Adriana Briseño-Garzón 《Cultural Studies of Science Education》2013,8(2):307-327

Latin American audiences living in their countries of origin are poorly understood as museum learners due to the scarcity of research in this field. Through a case study approach, I investigate and report on the ways of learning of 20 Mexican family groups. In particular, I examine the influence of the Mexican sociocultural context on the participant family members’ learning outcomes from a Mexican science museum. Conducted in Universum Museo de las Ciencias, a science museum located in Mexico City, this research study is based on the premise that understanding the role of the sociocultural elements of learning is essential to understanding the nature of learning in museums. The cognitive and social outcomes of the participants are discussed in the light of the sociocultural elements that define Mexicans as museum learners.  相似文献   

Memoria y competencia inferencial en niños: un estudio preliminar     

Angel Rivière  María Teresa Cascallana 《Infancia y Aprendizaje》2013,36(25):105-113

Resumen

Se contrasta la hipótesis de un posible efecto de facilitación mediante la representación previa de unas premisas sobre la competencia lógica de niños de nueve años. Los resultados no permiten confirmar la incidencia de ese efecto cuando la tarea exigida está por encima de la competencia lógica actual de los sujetos.  相似文献   

Memoria incidental e intencional en preescolares     

Miguel Angel González  Francisco Valle 《Infancia y Aprendizaje》2013,36(27-28):223-235

Resumen

En general, se ha mantenido que los niños en edad preescolar recuerdan mejor en tareas de aprendizaje incidental que en las de aprendizaje intencional. En este estudio se ha reexaminado esta cuestión y se ha visto que no existe tal diferencia. Niños de 3 a 5 reconocieron de modo semejante una serie de objetos y dibujos, tanto si se les había advertido previamente que debían recordar como si no. El estudio ha demostrado asimismo, y en concordancia con otros trabajos, que el recuerdo no es independiente del nivel de conocimiento ni de la edad del niño. En virtud de estos resultados se hace una interpretación de la memoria infantil acorde con la teoría de los niveles de procesamiento.  相似文献   

那些曾经，溢过阳光     

Angel 《中学生电脑》2008,(6):22

阳光温暖得让人有些沉醉。故事的开始似乎总是这样一个浪漫的午后,有某些事物在继续奔跑,延伸。带走一些忧伤,似乎也带来一些快乐。一体育课上绕着操场一圈圈地跑着,豆子从后面跑上来,拉着我的手径直从操场中间穿过,坐在一个完全暴露在阳光下的斜坡上,因为豆子说她冷得快见马克思了。于是我们坐在水泥地上,也没有想  相似文献   

Intermittent hypoxia exposure in a hypobaric chamber and erythropoietin abuse interpretation   总被引：1，自引：0，他引：1  

Abellan R  Ventura R  Remacha AF  Rodríguez FA  Pascual JA  Segura J 《Journal of sports sciences》2007,25(11):1241-1250

The aim of this study was to assess the effect of intermittent hypoxia exposure on direct and indirect methods used to evaluate recombinant human erythropoietin (rhEPO) misuse. Sixteen male triathletes were randomly assigned to either the intermittent hypoxia exposure group (experimental group) or the control normoxic group (control group). The members of the experimental group were exposed to simulated altitude (from 4000 to 5500 m) in a hypobaric chamber for 3 h per day, 5 days a week, for 4 weeks. Blood and urine samples were collected before and after the first and the final exposures, and again 2 weeks after the final exposure. While serum EPO significantly increased after the first [from a mean 8.3 IU x l(-1) (s = 3.2) to 16.6 IU x l(-1) (s = 4.7)] and final exposures [from 4.6 IU x l(-1) (s = 1.4) to 24.8 IU x l(-1) (s = 9.3)], haemoglobin, percentage of reticulocytes, and soluble transferrin receptor were not elevated. Second-generation ON/OFF models (indirect rhEPO misuse detection) were insensitive to intermittent hypoxia exposure. The distribution of the urinary EPO isoelectric profiles (direct rhEPO misuse detection) was altered after intermittent hypoxia exposure with a slight shift towards more basic isoforms. However, those shifts never resulted in misinterpretation of results. The intermittent hypoxia exposure protocol studied did not produce any false-positive result for indirect or direct detection of rhEPO misuse in spite of the changes in EPO serum concentrations and urinary EPO isoelectric profiles, respectively.  相似文献   

Ethnic and Racial Identity in Adolescence: Implications for Psychosocial,Academic, and Health Outcomes     

Deborah Rivas‐Drake  Eleanor K. Seaton  Carol Markstrom  Stephen Quintana  Moin Syed  Richard M. Lee  Seth J. Schwartz  Adriana J. Uma?a‐Taylor  Sabine French  Tiffany Yip  Ethnic  Racial Identity in the st Century Study Group 《Child development》2014,85(1):40-57

The construction of an ethnic or racial identity is considered an important developmental milestone for youth of color. This review summarizes research on links between ethnic and racial identity (ERI) with psychosocial, academic, and health risk outcomes among ethnic minority adolescents. With notable exceptions, aspects of ERI are generally associated with adaptive outcomes. ERI are generally beneficial for African American adolescents' adjustment across all three domains, whereas the evidence is somewhat mixed for Latino and American Indian youth. There is a dearth of research for academic and health risk outcomes among Asian American and Pacific Islander adolescents. The review concludes with suggestions for future research on ERI among minority youth.  相似文献