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51.
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The displacement of the golf ball struck by a driving club is affected by several player characteristics and equipment parameters and their interrelationships. Some modelling and simulation studies have shown a relationship between shaft length and clubhead speed, supported by a few experimental studies. The aim of the present study was to examine the relationship between driver length and ball launch conditions in an indoor test facility using a ball launch monitor. Nine males considered to be skilled golfers participated in the study. Four driving clubs of total length 117, 119, 124, and 132 cm were assembled from commercially available components and were used to strike golf shots while initial ball velocity, backspin rate, and launch angles were measured. Statistical analysis identified a significant difference in initial launch speed due to club length, a significant difference between participants, but no difference between the trials for a given golfer. A positive trend was noted between backspin and launch angle for all four clubs, and significant inverse associations between initial launch speed and backspin rate and launch angle. However, the combined launch conditions associated with increasing length were not considered optimal, with uncontrolled swingweight and moment of inertia effects considered to be limiting factors.  相似文献   
53.
A report is given of the investigation of the iodine content of oyster shells taken from the reefs found in the Gulf of Mexico. The pulverized shells as sold on the market contain 200 to 300 parts per billion of iodine. Water soluble and alcohol soluble iodides appear to be absent. The granulated undried shells contain 500 parts per billion of iodine. Apparently there is a loss of iodine due to the temperature at which the pulverized shells are dried.  相似文献   
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Abstract

A large body of evidence now shows that higher protein intakes (2–3 times the protein Recommended Dietary Allowance (RDA) of 0.8 g/kg/d) during periods of energy restriction can enhance fat-free mass (FFM) preservation, particularly when combined with exercise. The mechanisms underpinning the FFM-sparing effect of higher protein diets remain to be fully elucidated but may relate to the maintenance of the anabolic sensitivity of skeletal muscle to protein ingestion. From a practical point of view, athletes aiming to reduce fat mass and preserve FFM should be advised to consume protein intakes in the range of ~1.8–2.7 g kg?1 d?1 (or ~2.3–3.1 g kg?1 FFM) in combination with a moderate energy deficit (?500 kcal) and the performance of some form of resistance exercise. The target level of protein intake within this recommended range requires consideration of a number of case-specific factors including the athlete's body composition, habitual protein intake and broader nutrition goals. Athletes should focus on consuming high-quality protein sources, aiming to consume protein feedings evenly spaced throughout the day. Post-exercise consumption of 0.25–0.3 g protein meal?1 from protein sources with high leucine content and rapid digestion kinetics (i.e. whey protein) is recommended to optimise exercise-induced muscle protein synthesis. When protein is consumed as part of a mixed macronutrient meal and/or before bed slightly higher protein doses may be optimal.  相似文献   
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The academic library, given its often privileged position on campus, is the information source that can include directional as well as general campus facts among the myriad of print and e-resources for reference. Also, an academic library's audiences can be quite varied and include prospective students or parents seeking more general knowledge of the building and the campus. Many times this need for information drives patrons to the library service desks. Sometimes, especially during the high-demand seasons of new student orientation and beginning of the fall semesters, the desk is so busy that many patrons will leave because they don't have the time to wait. To address this immediate need for information, Texas Tech University Libraries developed an interactive kiosk to provide general information for frequently asked questions in a more efficient, creative, and interactive way. The kiosk provides a fun method of satisfying a patron's information needs without the requirement of a staff member or the need to wait in line for help. The kiosk is available as long as the Library is open and provides a variety of useful answers to general questions, as well as facts about the Library.  相似文献   
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Presidential election campaigns provide opportunities for parents to socialize their children to become politically engaged citizens. However, news coverage of the 2016 U.S. presidential campaign contained inappropriate content, leading parents to possibly restrict or denigrate rather than encourage child campaign news consumption. This study built on literatures in political socialization and parental mediation to explore mediation of campaign news coverage. Data from a representative sample of American parents during the Autumn of 2016 revealed that co-viewing, active mediation, and restrictive mediation were relatively common. The predictors of mediation included political variables, parenting orientations, and child factors, with the latter two often interacting with one another. The results have implications for how we conceptualize both political socialization and parental mediation.  相似文献   
59.
A recent focus among communication scholars, the study of contradiction and paradox illuminates the inherent irrationality of organizing. The following case study examines how youth labor – cast as play – functions as a series of tensions and contradictions in the day-to-day construction of work(er) between adults and youth. Mirroring the popular reality TV show, The Apprentice, the program under study communicated contradictory messages about youth work(ers) in terms of: (1) proving/discounting oneself as worker, (2) demanding confidence while orchestrating uncertainty and (3) playing along versus being playful in the organizationally prescribed framework, effectively dismissing work(ers) essential to the functioning of the organization. My analysis demonstrates how the framing of youth’s work as a game delegitimized youth work(ers) resulting in potentially exploitative working conditions, and serves as a call to communication scholars to better account for youth as workers, while pointing to similar implications for other types of provisional and contingent work(ers).  相似文献   
60.
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