The influence of intermittent high-intensity shuttle running and fluid ingestion on the performance of a soccer skill

The aim of this study was to examine the effect of intermittent high-intensity shuttle running and fluid ingestion on the performance of a soccer skill. Nine semi-professional soccer players volunteered to participate in the study. Their mean (± _sx ) age, body mass and maximal oxygen uptake were 20.2 ± 0.4 years, 73.2 ± 1.8 kg and 59.1 ± 1.3 ml·kg^-1 ·min^-1 respectively. The players were allocated to two randomly assigned trials: ingesting or abstaining from fluid intake during a 90 min intermittent exercise protocol (Loughborough Intermittent Shuttle Test:LIST).This test was designed to simulate the minimum physical demands faced by soccer players during a game. Before and immediately after performance of the test,the players completed a soccer skill test and a mental concentration test. Performance of the soccer skill test after the 'no-fluid' trial deteriorated by 5% (P ? 0.05),but was maintained during the fluid trial. Mean heart rate, perceived exertion, serum aldosterone, osmolality, sodium and cortisol responses during the test were higher (P ? 0.05) in the 'no-fluid' trial than in the fluid trial. The results of this study suggest that soccer players should consume fluid throughout a game to help prevent a deterioration in skill performance.     

Preparing for the Silver Tsunami: The Demand for Higher Education Among Older Adults

Over the next decade, Baby Boomers will be reaching retirement age in large numbers and the U.S. will be undergoing one of the most significant demographic shifts in its history. This demographic shift has important implications for the role of higher education as a provider of lifelong learning and for the changing composition of postsecondary institutions. Using data from the 2005 National Household Education Survey, the results of this study informs the higher education community about this emerging student market segment as a way to help us better respond to older adults?? demand for formal learning in postsecondary institutions.     

论"程菲跳"与双冠王程菲

程菲是中国体操队一名年仅17岁的女子体操运动员,她用科学态度坚持刻苦训练,充分发挥自身的弹跳能力和借助集体智慧,惊人地创造了“踺子后手翻转体180度接前直体空翻540度”世界女子跳马第一跳高难动作,这一高难动作被国际体联命名为“程菲跳”载入史册。“程菲跳”成就了程菲的跳马与自由体操的双冠王,而程菲精神是实现“程菲跳”的主动力。     

Diversity in the Information Seeking Behaviour of the Virtual Scholar: Institutional Comparisons

The logs of four universities using the OhioLINK journal system were evaluated for a period of fifteen months using deep log analysis methods in order to compare and contrast the information seeking behaviour of their users. Large differences were found, especially between the research and teaching universities. Methodological problems associated with making the comparisons are discussed in some detail especially in terms of defining online sessions.     

Website usage metrics: A re-assessment of session data

Metrics derived from user visits or sessions provide a means of evaluating Websites and an important insight into online information seeking behaviour, the most important of them being the duration of sessions and the number of pages viewed in a session, a possible busyness indicator. However, the identification of session (termed often ‘sessionization’) is fraught with difficulty in that there is no way of determining from a transactional log file that a user has ended their session. No one logs out. Instead a session delimiter has to be applied and this is typically done on the basis of a standard period of inactivity. To date researchers have discussed the issue of a time out delimiter in terms of a single value and if a page view time exceeds the cut-off value the session is deemed to have ended. This approach assumes that page view time is a single distribution and that the cut-off value is one point on that distribution. The authors however argue that page time distribution is composed of a number of quite separate view time distributions because of the marked differences in view times between pages (abstract, contents page, full text). This implies that a number of timeout delimiters should be applied. Employing data from a study of the OhioLINK digital journal library, the authors demonstrate how the setting of a time out delimiter impacts on the estimate of page view time and the number of estimated session. Furthermore, they also show how a number of timeout delimiters might apply and they argue that this gives a better and more robust estimate of the number of sessions, session time and page view time compared to an application of a single timeout delimiter.     

西北风蚀区植被覆盖防治土壤退化的机理及研究进展

土壤退化是制约西北地区环境质量和农业可持续发展的主要因素.本文简要介绍了土壤退化的概念、产生原因、分类;西北地区产生土壤退化的缘由、类型和现状;详细阐述了植被覆盖防止土壤退化的机理及研究进展;最后,提出了在该领域今后研究的方向.     

Six into One: The Contradictory Art School Curriculum and how it Came About

This article reports historical research which sought to understand the present‐day post‐secondary art curriculum through analysing its history in terms of changes in conceptions of art. It found that there have been six distinctive curricula: Apprentice, Academic, Formalist, Expressive, Conceptual and Professional. As a new curriculum has been introduced, it has co‐existed with much contained in a previous one. Most of the curriculum changes have taken place in the past 65 years. During this time, there has been a massive expansion in the education of artists and at the same time art schools accommodated first modernism and then post‐Duchampian aesthetics. A conclusion is that this has made for a very crowded curriculum. Moreover, despite there being an ever increasing choice of things a student might learn, it appears that there is nothing which all students have to learn. It can be problematic that one part of the curriculum is in contradiction to another part, and moreover this lack of a core raises fundamental, ontological questions about what art as a discipline is.     

基于证据推理理论的新产品开发项目投资风险评价方法

针对新产品开发项目投资风险评价信息不完全和不准确的问题,引入了证据推理理论和方法,建立包含否定性指标与非否定性指标的新产品开发项目投资的风险评价指标体系,结合实例进行了实证研究。研究表明该方法具有可操作性,并可以为企业进行研发项目投资前期的预测和决策提供科学和较为准确的依据。     

Defining'science-based targets'

The 2015 Paris Agreement to keep global warming well below 2℃above pre-industrial levels and aim towards limiting warming to 1.5℃marked a wa-tershed in planetar...