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191.
192.
Michael E. Gluck 《Research Policy》1987,16(6)
Growth in the industrial support of university research in the life sciences and more specifically in biotechnology has raised questions concerning its effects, both positive and negative, on the educational experiences of graduate students and post-doctoral fellows. A survey of 693 graduate students and post-doctoral fellows at six research intensive universities in the United States reveals that 19 percent of the responding students and fellows receive direct industry support for their research or training and that another 15 percent work with faculty advisors supported by industrial funds. On average students and fellows in this sample believe that the benefits of relationships with private firms outweigh the risks. In addition, students funded by private firms are more likely than those without industry connections to report patents resulting from their research. No relationship is found between industry support and young scientists' career plans or their rating of the quality of their educational experiences. However, the data suggest the existence of some risks: industry support is associated with fewer or delayed publications, inhibition of scientific communication on the part of some trainees, and some restrictions on students' and fellows' research. In a few cases, students are supported by funds from companies in which faculty advisors hold equity, a situation that creates potential conflicts of interest for students' mentors. To protect students, university administrators must monitor the relationships with industry that give rise to these potential problems. Future research into industrial support of research and training is needed to extend these results. 相似文献
193.
194.
Michael J Shoemaker Heather Hurt Leah Arndt 《Cardiopulmonary Physical Therapy Journal》2008,19(3):75-83
Purpose: To conduct a systematic review of the evidence regarding the efficacy of exercise training in the management of cystic fibrosis (CF).Methods: Articles were found by searching PEDRO, MEDLINE, and CINAHL databases. Included articles involved exercise-related interventions for long-term adaptations (ie, not acute effects of exercise). Articles were excluded if the language was other than English or if other non-exercise interventions were used. Date of publication was not a factor for exclusion. Two independent reviewers evaluated the included articles using Sackett''s levels of evidence and select scoring criteria.Results: Twelve articles were eligible for inclusion. Interventions studied included various aspects of exercise training: anaerobic, aerobic, or resistance training. Study end-points included pulmonary function, aerobic capacity, strength, and health-related quality of life (HRQL).Conclusions: Exercise training in individuals with CF is beneficial, with aerobic and resistance training having the greatest support in the literature for improved aerobic capacity and strength, respectively. Exercise training does not appear to have an effect of improving pulmonary function, but may have a preservation effect. Strong conclusions about improvement in HQRL from exercise training cannot be made. However, greater consistency in measuring this outcome is needed in future trials. There is a paucity of evidence regarding the role of exercise training in reducing hospitalization and health care utilization, and questions raised by this review should be considered in the design of future trials.Key Words: cystic fibrosis, aerobic exercise, review 相似文献
195.
196.
The purpose of this study was to compare measures of body size in two samples of youth baseball players with normative data from the United States National Center for Health Statistics (NCHS) growth charts. One sample of youth baseball players participated in a local little league. The second sample of youth baseball players were members of eight of the twelve teams participating in the 1995 Dixie Youth World Series. Normative data for the United States (NCHS) were used as comparative data. Two trained anthropometrists measured standing height, sitting height, lower limb height, upper limb length, arm girth, calf girth, tricep skinfold, and abdomen skinfold on all participants. In both samples, pitchers, short stops, and first basemen were a more highly skilled group and exhibited larger body size (greater standing height, sitting height, lower limb height, upper limb length) than children who played at other positions. The standing height of local little league players was similar to the median of reference data at ages 7, 8, and 9 years. The standing height and weight of skilled players in both samples approximated the 75th percentile for standing height and weight at ages 10, 11, 12, and 13 years. The results suggest that baseball players exhibit larger body size than the normal population at young ages. Body size may be an important criterion used by coaches to select and assign young players to certain positions. 相似文献
197.
The aim of this study was to determine whether 3 weeks of intermittent normobaric hypoxic exposure at rest was able to elicit changes that would benefit multi-sport athletes. Twenty-two multi-sport athletes of mixed ability were exposed to either a normobaric hypoxic gas (intermittent hypoxic training group) or a placebo gas containing normal room air (placebo group). The participants breathed the gas mixtures in 5-min intervals interspersed with 5-min recovery periods of normal room air for a total of 90 min per day, 5 days per week, over a 3-week period. The oxygen in the hypoxic gas decreased from 13% in week 1 to 10% by week 3. The training and placebo groups underwent a total of four performance tests, including a familiarization and baseline trial before the intervention, followed by trials at 2 and 17 days after the intervention. Time to complete the 3-km run decreased by 1.7%[95% confidence interval (CI) = -0.6 - 3.9%] 2 days after, and by 2.3% (CI = 0.25 - 4.4%) 17 days after, the last hypoxic episode in the training relative to the placebo group. Substantial changes in the training relative to the placebo group also included increased reticulocyte count 2 days (23.5%; CI =-1.9 to 44.9%) and 12 days (14.6%; CI = -7.1 to 36.4%) post-exposure. The effect of intermittent hypoxic training on 3-km performance found in this study is likely to be beneficial, which suggests non-elite multi-sport athletes should expect such training to enhance performance. 相似文献
198.
Michael Hutter Christian Knebel Gunnar Pietzner Maren Schäfer 《Journal of Cultural Economics》2007,31(4):247-261
The article tests a couple of hypotheses relating to markets where demand is not taken as a given, but subject to sophisticated
and encompassing price-building strategies. The study uses a data set that provides quoted dealer prices for medium-sized
works of 100 leading visual artists from 1970 to 2004. These data are compared with auction price results for works by the
same artists. The study reports significant discrepancies with respect to the relationship between the age of artists and
prices paid for their works in the two markets, and with respect to general price developments in the two markets as measured
by indices.
相似文献
Michael HutterEmail: |
199.
We examined the psychological effects of rapid weight loss among a sample of 41 professional jockeys (mean age 30.9 years, s = 7.0). Participants completed the Brunel Mood Scale (BRUMS) and the Eating Attitudes Test-26 (EAT-26) to establish the relationships between rapid weight loss, mood, and attitudes towards eating. These instruments were administered on three occasions: at the jockeys' minimal weight (achieved through rapid weight loss), their optimal riding weight (when they were not excessively restricting their weight and felt healthy), and their relaxed weight (when there were no forthcoming light rides or no rides at all). It was hypothesized that when riding at minimal weight, jockeys would record a more negative mood profile compared with scores recorded at optimal or relaxed weights. The same trend was expected for eating attitudes. These hypotheses were supported as jockeys reported significantly more negative mood profiles and eating attitudes at minimal weight. The EAT-26 scores indicated the presence of disordered attitudes towards eating at this weight. These results suggest that jockeys' endeavours to reach the minimum weight limit stipulated by governing bodies are likely to jeopardize their psychological well-being. Dialogue surrounding the appropriateness of current weight regulations is therefore encouraged. 相似文献
200.
Workbook reading achievement of five second-grade girls was assessed under two teacher-contact contingencies. Under one contingency, teacher contacts were made during on-task behavior. Under the other contingency, differential reinforcement of an incompatible behavior (DRI) was in effect, with teacher contacts contingent on students' hand-raising behavior. Both reading achievement and time on task were greater under the on-task contingency than under DRI for hand raising. 相似文献