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171.
All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling.  相似文献   
172.
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   
173.
This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent.  相似文献   
174.
The interaction between functional and dysfunctional emotions, as one of the major tenets of the individual zones of optimal functioning (IZOF) model (Hanin, 2000), was studied in a sport specific setting. Fourteen female gymnasts performed three attempts of a compulsory balance beam routine at three different heights. Heart rate and self-report of functional and dysfunctional emotions were measured during each routine. These data revealed the effectiveness of inducting emotions by manipulating height. Also, performance decreased on the most challenging condition, (i.e., the first attempt on the highest height). Moderated hierarchical regression analysis revealed a significant interaction between functional and dysfunctional emotions only when the dysfunctional emotion level was low.  相似文献   
175.
This paper explores the relationship between firms’ R&D cooperation strategies and their propensity to introduce environmental innovations.Previous literature has supported that environmental innovations differ from other innovations as far as externalities and drivers of their introduction are concerned, highlighting mainly the importance of regulation to trigger them. Using data from the Community Innovation Survey on Spanish manufacturing firms (PITEC), this paper investigates specificities that affect rather how they are developed, and in particular the higher importance of R&D cooperation with external partners.The econometric estimations, controlling for selection bias, suggest that environmental innovative firms cooperate on innovation with external partners to a higher extent than other innovative firms. Furthermore, cooperation with suppliers, KIBS and universities is more relevant than for other innovators, whereas cooperation with clients does not seem to be differentially important. Finally, the results bespoke of a substitution effect between cooperation activities and the internal R&D effort.  相似文献   
176.
Soft Computing (SC) tools present a great potential in real-life problems related with engineering, industrial applications, medicine, finances, etc. In this special issue we present a set of seven papers that report original research about the use of SC techniques to solve the problems in the field of information access on the Web.  相似文献   
177.
襄樊市拥有丰厚的书法艺术文化,书法影响着襄樊城市形象塑造。书法作为景观组成元素对塑造襄樊城市整体形象、打造襄樊城市标识、开发设计襄樊城市旅游、营造襄樊古城商业营销环境等具有重要作用,书法景观建设是弘扬和设计襄樊城市形象不可缺少的基本手段与内容。  相似文献   
178.
In two experiments, we examined how preexposure to discriminative stimuli and introduction of a 21-day retention interval affected the latent inhibition (LI) and perceptual learning (PL) of rats in a choice-maze discrimination task. Experimental groups were preexposed to three wall patterns, one in each of three arms of a maze. Control groups were preexposed only to white arms. PL groups were trained to discriminate A versus B, and LI groups, to discriminate A or B versus C. The A and B patterns shared many elements not shared with the C pattern. In Experiment 1, both at the end of training and after the subsequent retention interval, the PL groups performed better than controls, whereas the LI groups performed worse. In Experiment 2, inserting the 21-day retention interval between preexposure and discrimination training disrupted final measures of LI but not PL performance. Implications for current concepts of PL and LI are discussed.  相似文献   
179.
Attempting to push early modern presentism to the radical, logical conclusion of a more personal historicism, this essay draws on a number of interpretive practices and theoretical insights – Stephen Greenblatt’s self-reflectivity, Toni Morrison’s ‘rememory’, Marianne Hirsch’s ‘postmemory’, bell hooks’s ‘passion of experience’, and Linda Charnes’s alternative historicism – to establish the ethical and interpretive significance of my own painful situatedness as an African American man in Renaissance/Early Modern studies. Specifically, I illustrate that significance in a reading of Richard Mulcaster’s Positions Concerning the Bringing Up of Children, a sixteenth-century educational treatise that responds, as I argue, to early modern educational access and social mobility with an insidiously complex, exclusionary admissions policy.  相似文献   
180.
Abstract

International higher education is a major source of revenue in many developed countries. Historically the top destination countries for international students have included USA, UK, France and Australia. The key countries where most international students are recruited from include China, India and other parts of Asia. The extant literature has mostly examined the factors influencing international students to study in Western countries. A new trend is now emerging with an accelerating growth of international students in countries such as China and other parts of Asia. This mixed-methods study addresses the gap in the literature by exploring the factors that influence international students’ choice to study undergraduate or postgraduate courses in China. The study found that China is becoming an important destination choice for international students due to the distinctiveness of the Chinese language, the rise of its universities in global rankings and the country’s economic growth.  相似文献   
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