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171.
Attitudes and approaches toward the collection, use, and care of color photographs have evolved enormously since the official arrival of commercially viable color photographic processes in the early twentieth century. This article traces the evolution of collection, exhibition, and preservation practices for works of art in color photography over the last few decades, as represented by one institution, The Metropolitan Museum of Art.  相似文献   
172.
173.
In this interview, conducted via email during August 2016, Dr. Arlene G. Taylor discusses her career as a cataloger, professor of cataloging and classification, and her work in professional associations. Topics include her early cataloging and teaching experiences, changes in both cataloging practice and the teaching of cataloging, subject analysis, and “aboutness” as compared with form/genre access, professional experiences outside the United States, and the future of MLIS programs.  相似文献   
174.
175.
Although static stretching (SS) is utilized during warm-up before training and competition, the results about its effects on performance remain controversial. We examined whether performing a stretch of short-to-moderate duration (<60 sec) in a single repetition produces a similar or different effect on speed and agility performance from the effect which is produced while performing the same stretch in multiple repetitions of the same total duration. According to a repeated measurement design, 40 trained males were randomly assigned to either (1) a single repetition group or (2) a multiple repetition group. The participants in each group performed five trials: a control trial (no stretches were performed) and four experimental trials of SS protocols consisting of five exercises performed at either 20 sec (2 × 10 in the second group), 30 sec (3 × 10 in the second group), 40 sec (4 × 10 in the second group) or 60 sec (6 × 10 in the second group) of total duration. A two-way repeated measures analysis of variance showed that the participants in both group improved their speed performance in response to the 20-sec trial, whereas agility remained unaffected. Data analysis also revealed that the repetition number did not affect speed and agility performance. These data suggest that SS of short duration (<30 sec) may actually improve acute speed performance, whereas SS of moderate duration may not hamper speed and agility performance. Moreover, the effects of SS protocols are related to the total duration of each exercise and not to the number of repetitions in which each exercise is performed.  相似文献   
176.
This study is designed to identify the underlying satisfaction dimensions gained through engagement in target shooting as a serious leisure pastime. The instrument design was based on the Leisure Satisfaction Scale. A total of 5502 useable surveys were collected through the Internet and a website related to target shooting and gun ownership. The results revealed eight dimensions: self-actualization, social interaction, location aesthetic, respite, physical benefit, connection and hedonic pleasure, which supplied the primary satisfiers of engaging in target shooting as a serious leisure activity. The demographic profile and dimensions of satisfaction may serve to dispel commonly held stereotypes of shooting hobbyists and those involved in gun ownership. The findings have important implications for leisure researchers and practitioners, to industry, both leisure and firearm related, and the target shooting community at large. This study adds to the literature of both target shooting and serious leisure.  相似文献   
177.
We examined the effectiveness of perceptual training on the performance of handball goalkeepers when anticipating the direction of both direct and deceptive 7-m throws. Skilled goalkeepers were assigned equally to three matched-ability groups based on their pre-test performance: a perceptual training group (= 14) received video-based perceptual training, a placebo training group (= 14) received video-based regular training and a control group received no training. Participants in the perceptual training group significantly improved their performance compared to both placebo and control groups; however, anticipation of deceptive throws improved less than for direct throws. The results confirm that although anticipating deception in handball is a challenging task for goalkeepers, task-specific perceptual training can minimise its effect and improve performance.  相似文献   
178.
This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3–2.0 h before the start (PRE: ~0500–0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L?1), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L?1), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L?1) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL?1) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L?1; cortisol, 1187 ± 209 and 867 ± 215 nmol · L?1). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.  相似文献   
179.
The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13–17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6–10 repetitions at 60–70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50–80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (< 0.01) and increase in fat-free mass (< 0.01), VO2peak (< 0.01), 1 RM for leg press (< 0.01) and bench press (< 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (< 0.05) and leptin (< 0.05), as well as in insulin resistance (< 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.  相似文献   
180.
This study aimed to (1) profile a professional boxer (23 years and 80 kg) with boxing-specific, muscle function, aerobic capacity and body composition tests, and (2) quantify how these measures varied during an 8-week preparation phase leading to, and post a state-Title Bout fought in the 76.2-kg class. A series of boxing-specific and muscle function tests were completed on 11 occasions: 9 prior and twice after the bout, each separated by approximately 2 weeks. The boxing test included 36 maximal punches (9 of each: lead and rear straights, lead and rear hooks) to a punching integrator measuring forces and velocity. Muscle function tests included countermovement jump, drop-jumps, isometric mid-thigh pull and isometric bench-press. Body composition was assessed using skin-fold measurements on three occasions and one dual energy X-ray absorptiometry scan. Aerobic capacity was assessed using 2 VO2 max tests. Leading up to the bout, performance decreased in isometric mid-thigh pull (8%), isometric bench-press (5%), countermovement jump (15%) and impact forces in 3 of 4 punches (4%–7%). Whereas measures of dynamic and isometric muscle function remained depressed or unchanged post competition, punching forces (6%–15%) and aerobic power (6%) increased. Data suggest the athlete may have super-compensated following rest as fatigue dissipated and further adaptation occurred.  相似文献   
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