The Relationship Between Running Economy and Biomechanical Variables in Distance Runners     

Marcus Peikriszwili Tartaruga  Jeanick Brisswalter  Leonardo Alexandre Peyré-Tartaruga  Aluísio Otávio Vargas Ávila  Cristine Lima Alberton  Marcelo Coertjens 《Research quarterly for exercise and sport》2013,84(3):367-375

In this study, we analyzed the relationship between running economy (RE) and biomechanical parameters in a group running at the same relative intensity and same absolute velocity. Sixteen homogeneous male long-distance runners performed a test to determine RE at 4.4 m.s^-1, corresponding to 11.1% below velocity at the ventilatory threshold. We found significant correlations between RE and biomechanical variables (vertical oscillation of the center of mass, stride frequency, stride length, balance time, relative stride length, range of elbow motion, internal knee, ankle angles at foot strike, and electromyographic activity of the semitendinosus and rectus femoris muscles). In conclusion, changes in running technique can influence RE and lead to improved running performance.  相似文献   

Thinking more deeply about networks in education   总被引：1，自引：0，他引：1  

Jorge Ávila de Lima 《Journal of Educational Change》2010,11(1):1-21

In education, initiatives to restructure and reculture schools through their involvement in intra- and inter-institutional networks have grown in number in recent years. Networks of teachers and schools (often linked to institutions outside education) are becoming a key focus of change efforts promoted by professionals and policymakers. However, in current research, writing and policymaking, the use of the network concept has been generally vague, normative and mostly instrumental. This paper develops a discussion of network concepts and proposes more systematic, less normative ways of addressing and researching network issues in education. It outlines a set of key dimensions of intra- and inter-organizational networks and makes a case for more a comprehensive research approach to these phenomena.  相似文献   

The presence of a stepfather and child physical abuse, as reported by a sample of Brazilian mothers in Rio de Janeiro     

Alexandre GC  Nadanovsky P  Moraes CL  Reichenheim M 《Child abuse & neglect》2010,34(12):959-966

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The Individualized Classroom Assessment Scoring System (inCLASS): Preliminary reliability and validity of a system for observing preschoolers’ competence in classroom interactions   总被引：2，自引：0，他引：2  

Jason T. Downer  Leslie M. Booren  Olivia K. Lima  Amy E. Luckner  Robert C. Pianta 《Early childhood research quarterly》2010

This paper introduces the Individualized Classroom Assessment Scoring System (inCLASS), an observation tool that targets children's interactions in preschool classrooms with teachers, peers, and tasks. In particular, initial evidence is reported of the extent to which the inCLASS meets the following psychometric criteria: inter-rater reliability, normal distributions and adequate range, construct validity, and validity. These initial findings suggest that the inCLASS has the potential to provide an authentic, contextualized assessment of young children's classroom behaviors. Future directions for research with the inCLASS are discussed.  相似文献   

Inerter-like devices used for vibration isolation: A historical perspective     

Willian M. Kuhnert  Paulo J. Paupitz Gonçalves  Diego F. Ledezma-Ramirez  Michael J. Brennan 《Journal of The Franklin Institute》2021,358(1):1070-1086

Recently, a lot of attention has been given to a mechanical device known as the inerter. It is a mechanical component that can be compared to a capacitor with two ungrounded terminals in the mechanical-electrical systems analogy. In this paper, it is shown that although the concept of an inerter as a separate mechanical element is relatively new, there are several well-established vibration isolation systems that exhibit similar behavior to a simple lumped parameter system containing an inerter. Through a review of the literature, a link is established between the old and new ideas. Furthermore, a comparison between the systems is carried out using the quantities of mechanical impedance and displacement transmissibility. The advantages and disadvantages of using the inerter in vibration isolation are discussed, and a simple way of improving the high-frequency performance without severely degrading the low-frequency performance is described.  相似文献   

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

Silva RP  Mündel T  Natali AJ  Bara Filho MG  Lima JR  Alfenas RC  Lopes PR  Belfort FG  Marins JC 《Journal of sports sciences》2011,29(7):725-732

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   

Information literacy: perceptions of Brazilian HIV/AIDS researchers     

Maria do Carmo Avamilano Alvarez  Ivan França Junior  Angela Maria Belloni Cuenca  Francisco I. Bastos  Helene Mariko Ueno  Cláudia Renata Barros  Maria Cristina Soares Guimarães 《Health information and libraries journal》2014,31(1):64-74

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Early Training in Oral Comprehension and Phonological Skills: Results of a Three-Year Longitudinal Study     

Maryse Bianco  Pascal Bressoux  Anne-Lise Doyen  Eric Lambert  Laurent Lima  Catherine Pellenq 《Scientific Studies of Reading》2013,17(3):211-246

A sample of 1,273 4-year-old children were followed for 3 years. The children participated in 1 of 2 comprehension training programs, or in a phonological awareness training program. The comprehension programs explored the possibility of improving young children's oral comprehension in an educational setting. The first focused on the component skills of comprehension; the second involved storybook reading. Phonological awareness and oral language comprehension skills were measured repeatedly in the course of the study. The data were analyzed using multilevel growth-curve models. The results showed that it is possible to improve oral comprehension if the training focuses on its component skills and extends over 2 semesters. When these conditions were met, training effects still existed 9 months after the program had ended. Finally, phonological training improved phonological awareness but not comprehension, and comprehension-skill training improved oral comprehension but not phonological awareness.  相似文献   

Establishment of higher education institutions and new firm entry   总被引：1，自引：0，他引：1  

Rui Baptista  Francisco Lima  Joana Mendonça 《Research Policy》2011,40(5):751-760

The presence of universities has generally been associated with technological entrepreneurship. But what is the real impact of new universities on the levels of firm creation in a region? The present paper uses policy evaluation methodologies and longitudinal data on the establishment of higher education institutions in Portuguese municipalities for the period 1992-2002 to examine its effect on entry rates of new firms in different sectors. We find that the establishment of a new university has a positive and significant effect on subsequent levels of knowledge based firm entry in municipalities, and a negative effect on the levels of entry in other sectors, such as low-tech manufacturing.  相似文献   

Gymnastics,Hygiene and Eugenics in Brazil at the Turn of the Twentieth Century     

Edivaldo Gόis Junior 《国际体育史杂志》2014,31(10):1219-1231

The aim of this study was to describe the influence of medical knowledge on the organisation of school gymnastics in Brazil, in the nineteenth century and at the beginning of the twentieth century. For this purpose, the following sources were used: PhD theses approved by the Faculties of Medicine in Rio de Janeiro and Bahia state, and documents from the Academia Nacional de Medicina and the Escola Normal de São Paulo. It was concluded that the hygienist mentality was fundamental for the diffusion of gymnastics in the Brazilian context.  相似文献