儿童青少年运动员的营养需要

1. 儿童青少年运动员应该食用多样化的食物，其中，蛋白质应占膳食总能量的12％-15％，碳水化合物至少占55％，而脂肪至多占30％。日常生活中如何吃才能满足这些要求呢？膳食指南宝塔提供了一条可行之道。2.有些营养素对热爱运动的儿童青少年运动员非常重要，要保证摄入充足，这些营养素是碳水化合物（包括纤维素）、维生素B6、维生素D、铁、钙、镁、锌、铬。科学合理、包罗各类食物的平衡膳食，对青少年运动员最大程度地全面摄取各种营养素，满足生长发育和运动训练的需要，是非常必要的。3.鼓励儿童青少年运动员在运动训练前、中、后进行补液，以避免脱水的发生。4.如果膳食合理平衡，就没必要额外补充营养品。     

Pre-season physiological characteristics of English first and second division soccer players.

This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS)     

State of the art of expert searching: results of a Medical Library Association survey.

OBJECTIVES: Medical Library Association (MLA) members were surveyed to gather background about the current state of expert searching in institutions. The survey results were intended to guide the recommendations of the Task Force on Expert Searching for promoting the importance of expert searching and implementing those recommendations. METHODS: MLA members were surveyed, and data obtained from the survey were compiled and analyzed to answer three general questions: what is the perceived value of searching skills to the institution, how do health sciences librarians maintain and improve their searching skills, and how are searching services promoted and/or mandated in the institution. RESULTS: There were 256 responses to the survey. Over 95% of the respondents saw their expert-searching skills were of value to their institutions, primarily through performing mediated searches and search consultations. Over 83% of the respondents believed that their searching skills had improved over the past 10 years. Most indicated that continued training was very important in maintaining and improving their skills. Respondents promoted searching services most frequently through orientations, brochures, and the libraries' Web pages. No respondent's institution mandated expert searching. Less than 2% of respondents' institutions had best practice guidelines related to expert searching, and only about 8% had guidelines or policies that identified situations where expert searching was recommended. CONCLUSIONS: The survey supports the belief that health sciences librarians still play a valuable role in searching, particularly in answering questions about treatment options and in providing education. It also highlights the need for more expert searching courses. There has been minimal discussion about the perceived need for expert-searching guidelines in the institutions represented by survey respondents.     

Google Scholar's Coverage of the Engineering Literature 10 years Later

In 2008 Meier and Conkling first tested Google Scholar's coverage of the engineering literature against citations gathered from the Compendex database. Since that time, other studies have used the same methodology and found improvement in Google Scholar's coverage. This study uses engineering dissertations from Proquest Dissertations & Theses to create a data set of citations for the comparison of fee-based databases, Compendex and Scopus, against Google Scholar. From 1950 to 2017 Google Scholar outperformed both Compendex and Scopus in discoverability of citations in nine engineering subjects. These results have implications for collection management and information literacy program planning for librarians.     

Print Media Standardisation and Professionalism

The independence of the media under Ghana’s Fourth Republic is assessed from the perspective of standards and professionalism. Using a qualitative method, the study shows that unethical practices are evident in the print media landscape in Ghana, and argues that this can be traced to four major spheres: educational qualification, existence of several professional associations, a weak regulatory body and “money matters”. Overall, the study argues that legalities form a minimal part of the independence of the Ghanaian media but concerns about freedom seem to be self-inflicted by the very media practitioners through their actions and sometimes questionable reportage.