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961.
In our paper we present an experimental study which investigated the possibility to project the need for information specialists serving knowledge workers in knowledge industries on the basis of an average university library serving their counterparts at a university. Information management functions, i.e. functions and processes related to information evaluation, acquisition, metadata creation, etc., performed in an average university library are the starting point of this investigation. The fundamental assumption is that these functions do not only occur in libraries but also in other contexts like, for instance, in knowledge industries. As a consequence, we try to estimate the need for information professionals in knowledge industries by means of quantitative methods from library and information science (Library Planning Model) and economics (input output analysis, occupational analysis). Our study confirms the validity of our assumption. Accordingly, the number of information specialists projected on the basis of university libraries is consistent with their actual number reported in national statistics. However, in order to attain a close fit, we had to revise the original research model by dismissing the split-up of information specialists into reader services and technical services staff. 相似文献
962.
Xue-Yan Wang Christian Fillafer Clara Pichl Stephanie Deinhammer Renate Hofer-Warbinek Michael Wirth Franz Gabor 《Biomicrofluidics》2013,7(4)
Microfluidic devices have emerged as important tools for experimental physiology. They allow to study the effects of hydrodynamic flow on physiological and pathophysiological processes, e.g., in the circulatory system of the body. Such dynamic in vitro test systems are essential in order to address fundamental problems in drug delivery and targeted imaging, such as the binding of particles to cells under flow. In the present work an acoustically driven microfluidic platform is presented in which four miniature flow channels can be operated in parallel at distinct flow velocities with only slight inter-experimental variations. The device can accommodate various channel architectures and is fully compatible with cell culture as well as microscopy. Moreover, the flow channels can be readily separated from the surface acoustic wave pumps and subsequently channel-associated luminescence, absorbance, and/or fluorescence can be determined with a standard microplate reader. In order to create artificial blood vessels, different coatings were evaluated for the cultivation of endothelial cells in the microchannels. It was found that 0.01% fibronectin is the most suitable coating for growth of endothelial monolayers. Finally, the microfluidic system was used to study the binding of 1 μm polystyrene microspheres to three different types of endothelial cell monolayers (HUVEC, HUVECtert, HMEC-1) at different average shear rates. It demonstrated that average shear rates between 0.5 s−1 and 2.25 s−1 exert no significant effect on cytoadhesion of particles to all three types of endothelial monolayers. In conclusion, the multichannel microfluidic platform is a promising device to study the impact of hydrodynamic forces on cell physiology and binding of drug carriers to endothelium. 相似文献
963.
Abstract We examined the effects of instructional and motivational self-talk on centre of mass displacement and hip kinematics during the vertical jump. Twenty-four male rugby union players (age 21.1 years, s = 3.5; body mass 81.0 kg, s = 8.9; height 1.80 m, s = 0.06) performed three vertical jump tests, with a 2 min rest between jumps. Before each jump, participants engaged in one of three counterbalanced interventions (motivational self-talk, instructional self-talk or no-intervention). Motivational self-talk led to greater centre of mass displacement (0.602 m, s = 0.076; P = 0.012) than the no-intervention control (0.583 m, s = 0.085). Centre of mass displacement did not differ between instructional self-talk and the control condition or between motivational and instructional self-talk. Motivational (100.75°, s = 16.05; P = 0.001) and instructional self-talk (106.14°, s = 17.04; P = 0.001) led to greater hip displacement than the no-intervention control (94.11°, s = 17.14). There was also a significant difference in hip displacement between motivational and instructional self-talk (P = 0.014), although there was no difference between instructional self-talk and the control condition. Motivational (451.69 °/s, s = 74.34; P = 0.008) and instructional self-talk (462.01 °/s, s = 74.37; P = 0.001) led to greater hip rotation velocity than the no-intervention control (434.37 °/s, s = 75.37), although there was no difference between the two self-talk interventions. These results indicate that self-talk may influence performance and technique during the vertical jump in male rugby players. 相似文献
964.
AbstractUsing a scrambled sentence priming protocol, the first aim of this study was to investigate whether differences in novel exercise-related goals existed between participants primed with motivational or non-motivational material (i.e. autonomous, controlled or neutral primes). The second aim was to explore whether an indirect effect was present between priming condition and the goal-related exercise sessions that individuals performed over the week following administration of the prime. No effects were observed across priming conditions with respect to subjective vitality, goal concordance and the frequency with which participants planned to exercise. However, autonomy-primed individuals set goals for their exercise sessions that were significantly longer in intended duration (M = 57.72 min, SD = 37.42) than those set by their counterparts in both the controlled-prime condition (M = 44.12 min, SD = 27.78) and the neutral-prime condition (M = 37.10 min, SD = 20.47). Bootstrapped analyses also revealed a significant indirect relationship between prime and exercise behaviour, with the autonomy prime predicting longer goal-based exercise sessions, via the effect on the duration of participants’ intended exercise sessions. These findings highlight the potential influence that priming autonomous motivation may have on individuals’ exercise aspirations, as well as the way in which primes may indirectly shape exercise engagement. 相似文献
965.
Laurence P. Birdsey Matthew Weston Mark Russell Michael Johnston Christian J. Cook 《Journal of sports sciences》2013,31(19):2169-2174
ABSTRACTTo examine responses to an International netball tournament, female athletes (n= 11) played three matches over consecutive days. External (accelerometry) and internal (heart rate; HR, session; sRPE, and differential; dRPE, rating of perceived exertion) load measures quantified match intensity. On match-day mornings, and three days after match 3, well-being (brief assessment of mood; BAM+), biochemical (creatine kinase concentration; CK), neuromuscular (jump height; JH, peak power output; PPO) and endocrine function (salivary cortisol; C, testosterone; T, concentrations) were assessed. External load was similar between matches whereas dRPE and sRPE were greatest for match 3. Following match 1, CK increased, whereas BAM+, JH, C and T decreased. Following two matches, BAM+, PPO, and T decreased with CK increasing versus baseline. Following consecutive matches, CK (likely moderate; 27.9% ± 19.5%) and C (possibly moderate; 43.3% ± 46.8%) increased, whilst BAM+ (possibly moderate; ?20.6% ± 24.4%) decreased. Three days post-tournament BAM+, T, PPO, and JH decreased. Mid-court elicited higher mean HR (possibly moderate; 3.7% ± 3.8%), internal and external intensities (possibly very large; 85.7% ± 49.6%) compared with goal-based positions. Consecutive matches revealed a dose–response relationship for well-being and physiological function; a response evident three days post-tournament. 相似文献
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