Circadian rhythm effect on physical tennis performance in trained male players

To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h^?1; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon.     

我不是软蛋!

多年以来,外籍内线球员在NBA似乎有了固定的模板——传球漂亮,中距离篮子很准,然后他们会自觉或不自觉的远离篮下禁区,他们为自己找到的借口是：我们用头脑打球。可是,傻子都知道,是汉子,就该杀到禁区里面去;是爷们,就捍卫属于自己的篮下三尺领土。     

拉马库斯·阿尔德里奇 小生怕怕

他并不是天生的篮球神童,甚至到8年级身高长到了6尺7寸时,他在达拉斯Leagoville中学打球还只是被大一点的同伴看做能传球的木桩;他打出了许多怪兽级的比赛：18投16中得到39分,9个篮板,6次盖帽;高中时代他与克里斯·波什的对抗中拿到24分12个篮板,压倒了波什的18分10个篮板;他是个绝对的乖孩子,在课堂上总是恭敬的对老师说着“是的,先生”和“不,先生”,从不喝酒,     

A study of students' perceptions of the organisation and effectiveness of fieldwork in earth sciences education

This paper reports the findings of a preliminary evaluation of an in-service training programme designed for practising geology/earth science teachers in Portuguese high schools and intended to enhance the effectiveness of fieldwork activities organised by them for their students. Among the points particularly stressed during the in-service training were that students should be adequately prepared for fieldwork through classroom-based activities prior to the fieldwork itself and that to arrive at the maximum educational benefit for the students, they should be involved in collaborative group-based investigation. The findings, derived from an enquiry among students following their exposure to fieldwork, revealed that in both these aspects teachers failed to put theory into practice, probably as the result of a lack of confidence to implement novel procedures. On the positive side, the students reported that they enjoyed the social interaction with other students that the fieldwork made possible and the opportunity to work independently of the teachers.     

Interoperability frameworks and enterprise architectures in e-government initiatives in Europe and the United States

Public administrations have been very much concerned since the 1980s about the need of avoiding vendor lock-in when procuring themselves with information technology (IT) infrastructure. The boost of e-government that has taken place in recent years has put this concern again in the agenda of public administrations. Interoperability has shown up as a principle in the conception and deployment of the e-government initiatives, and the interoperability frameworks have been the tool for implementing the principle. In this paper, the use of the interoperability frameworks and of the enterprise architectures within the e-government initiatives is surveyed. The scope of the survey is Europe and the United States. As far as the author is aware, all trends in interoperability policy fall within the scope of the survey. The survey is focused on the methodological tools that e-government agencies have devised for achieving the interoperability at the public administrations. The tools are interoperability frameworks and enterprise architectures.     

Gender differences in adolescents’ choice of heroes and admired adults in five countries

Seven hundred and sixty-eight adolescents from five countries and regions (USA, Spain, Hong Kong, Qatar, and Malaysia), aged 13–19 (M?=?15.78; SD?=?1.28) years, responded to a questionnaire designed to determine who was their most admired famous adult or hero. Male heroes clearly outnumbered admired females (73.3% vs. 26.7%). There was a pattern of same-sex choices, but it was more likely for girls to choose male heroes than for boys to choose females. Over half of the admired adults were athletes, and movie, television, and music stars. Regarding the personally known adults, there was a more balanced choice of males and females, with parents as the most frequent choice. Results suggest that society continues to fail in providing an adequate supply of female role models.     

Epidemiology of injuries in First Division Spanish football

Abstract

The aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively.     

How do your rivals’ releasing dates affect your box office?

In this paper, we study to what extent a movie’s box-office receipts are affected by the temporal distribution of rival films. We propose a reduced-form empirical model to measure and test competition effects among films released close to each other in a standard regression framework. Such an analysis is appealing in terms of its policy implication and may provide guidance to distributors to decide on their releasing dates of their firms. We estimate this model using information on the films released in five countries: the USA, the United Kingdom, Germany, France and Spain. The geographical dimension of our data set permits us to control for unobserved heterogeneity among films released using panel data techniques, which allows us to evaluate the individual and specific effects of each film. Thus we deal with one of the most relevant features of the movie market, namely the presence of highly differentiated products.