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181.
Jodi Shepherd Marc Langston 《Library Collections, Acquisitions, and Technical Services》2013,37(1-2):34-41
The California State University (CSU) system has a history of consortial purchasing of electronic resources. Its most recent endeavor is consortial Patron Driven Acquisition (PDA) of e-books. Two PDA e-book pilots, funded by the CSU Chancellor's Office, were conducted in 2011 and 2012. The aim of the pilots was to reduce duplication of e-books on CSU campuses, and determine if consortial PDA is appropriate for the CSU. This article provides an overview of CSU's cooperative collection development efforts, results from both pilots, and addresses how a consortial PDA program affects collection development locally on one CSU campus. 相似文献
182.
A comprehensive study involving numerical analysis and experimental validation of temperature transients within a microchamber was performed for thermocycling operation in an integrated centrifugal microfluidic platform for polymerase chain reaction (PCR) amplification. Controlled heating and cooling of biological samples are essential processes in many sample preparation and detection steps for micro-total analysis systems. Specifically, the PCR process relies on highly controllable and uniform heating of nucleic acid samples for successful and efficient amplification. In these miniaturized systems, the heating process is often performed more rapidly, making the temperature control more difficult, and adding complexity to the integrated hardware system. To gain further insight into the complex temperature profiles within the PCR microchamber, numerical simulations using computational fluid dynamics and computational heat transfer were performed. The designed integrated centrifugal microfluidics platform utilizes thermoelectrics for ice-valving and thermocycling for PCR amplification. Embedded micro-thermocouples were used to record the static and dynamic thermal responses in the experiments. The data collected was subsequently used for computational validation of the numerical predictions for the system response during thermocycling, and these simulations were found to be in agreement with the experimental data to within ∼97%. When thermal contact resistance values were incorporated in the simulations, the numerical predictions were found to be in agreement with the experimental data to within ∼99.9%. This in-depth numerical modeling and experimental validation of a complex single-sided heating platform provide insights into hardware and system design for multi-layered polymer microfluidic systems. In addition, the biological capability along with the practical feasibility of the integrated system is demonstrated by successfully performing PCR amplification of a Group B Streptococcus gene. 相似文献
183.
Anne-Line Balduck Marc Buelens Renaat Philippaerts 《Research quarterly for exercise and sport》2013,84(3):379-383
Abstract Tests were made with the hand carrying weights of 0.2, 3.1, and 16.6 kg. during a 72° horizontal adductive arm swing of maximal speed timed at 12° intervals. Five practice swings and 20 trials, under each condition, were performed by 60 male subjects. Reliability coefficients were high. The first 24° of movement exhibited declining acceleration, followed by linearly increasing acceleration for the 24°—60° interval and deceleration for the next 12°. Compared with static strength in the movement position, action strength computed from acceleration was much greater with the heaviest weight and considerably less with the light weights. The correlation between static strength and speed was quite low for the normal arm swing but increased with added weight, becoming r = .76 for the heaviest. There was little correlation of individual differences in speed between different phases of movement or between movements with light and heavy weights. Specificity was high, although correlations were made for attenuation. 相似文献
184.
Abstract Data were collected on the number of first yellow cards awarded during 857 games, over six seasons (1996 – 2002), played in the Football Association (FA) Cup. Overall, a significantly higher number of yellow cards were awarded against the away team, while a non-linear relationship between crowd size and yellow cards was observed. In general, the probability of a yellow card being awarded against the home team decreased as crowd size increased, but was attenuated for the largest crowd sizes. Crowd size may be related to the probability of the home team receiving a yellow card in two potential ways. Crowd noise may be a decision-making heuristic whereby the likelihood that an incident is a foul is increased when accompanied by crowd noise. Alternatively, referees may seek to appease the crowd and are more likely to do so as crowd size increases. The present findings have implications for the training of match officials and for coaches and players as they prepare to play away from home. 相似文献
185.
Abstract Coping strategies are important for performance in sport and individual differences may contribute to the coping strategies adopted by athletes. In this study, we explored the main and interactive effects of the big five personality dimensions on sport-related coping and compared personality profiles of discrete groups of athletes. Altogether, 253 athletes (mean age 21.1 years, s = 3.7) completed the NEO-FFI (Costa & McCrae, 1992), and the Coping Function Questionnaire for Sport (Kowalski & Crocker, 2001). Results showed that extraverted athletes, who were also emotionally stable and open to new experiences (a three-way interaction effect), reported a greater use of problem-focused coping strategies. Conscientious athletes (main effect), and athletes displaying high levels of extraversion, openness, and agreeableness (a three-way interaction effect), reported a greater use of emotion-focused coping strategies, and athletes with low levels of openness, or high levels of neuroticism (main effects), reported a greater use of avoidance coping strategies. Different personality characteristics were observed between higher-level and lower-level athletes, between men and women athletes, and between individual and team sport athletes. These findings suggest that the five-factor model of personality can help distinguish various levels of athletic involvement and can help identify the coping strategies athletes are likely to adopt during participation. 相似文献
186.
Andy Marc Adrien Sedeaud Marion Guillaume Melissa Rizk Julien Schipman Juliana Antero-Jacquemin 《Journal of sports sciences》2013,31(6):524-532
AbstractAs opposed to many other track-and-field events, marathon performances still improve. We choose to better describe the reasons for such a progression. The 100 best marathon runners archived from January 1990 to December 2011 for men and from January 1996 to December 2011 for women were analysed. We determined the impact of historical, demographic, physiological, seasonal and environmental factors. Performances in marathons improve at every level of performance (deciles). In 2011, 94% of the 100 best men athletes were African runners; among women athletes they were 52%. Morphological indicators (stature, body mass and Body Mass Index (BMI)) have decreased. We show a parabolic function between BMI and running speed. The seasonal distribution has two peaks, in spring (weeks 14 to 17) and autumn (weeks 41 to 44). During both periods, the average temperature of the host cities varies close to optimal value for long distance race. African men and women runners are increasingly dominating the marathon and pushing its record, through optimal eco-physiological conditions. 相似文献
187.
Adrien Sedeaud Andy Marc Julien Schipman Karine Schaal Mario Danial Marion Guillaume 《Journal of sports sciences》2013,31(12):1146-1154
In a context of morphological expansion of the general population, how do athletes follow such a pattern of anthropometric growth? Is there any relation to performance? Biometric data including mass, height, body mass index (BMI) and age were collected for 50,376 American athletes representing 249,336 annual performers playing in professional baseball, football, ice hockey and basketball. Distributions by mass in National Football League (NFL) players are described by periods. Field goals have been studied in relation to players’ height in the National Basketball Association (NBA). Between 1871 and 2011, athletes from the four sports have increased significantly in mass, height and BMI, following a multi-exponential function series. Consequently, biometric differences between athletes and the general population are increasing gradually. Changes in the mass distribution within the NFL show the emergence of a biometrical specificity in relation to the field position. At the professional level, performance remains structured around precise biometric values. In the NBA, a height-attractor at 201.3 ± 6.3 cm for the best scorers is invariant, regardless of the level of play. These results suggest that laws of growth and biometrics drive high-level sport and organise performance around the specific constraint of each field position. Discrepancies between some mass and height developments question the (disproportionate) large mass increase (relative to the height increase) during the 1980s and 1990s. 相似文献
188.
Optical based analysis in microfluidic and lab-on-a-chip systems are currently considered the gold standard methodology for the determination of end point reactions for various chemical and biological reaction processes. Typically, assays are performed using bulky ancillary apparatus such as microscopes and complex optical excitation and detection systems. Such instrumentation negates many of the advantages offered by device miniaturisation, particularly with respect to overall portability. In this article, we present a CO2 laser ablation technique for rapidly prototyping on-chip planar lenses, in conjunction with capillary action based autonomous microfluidics, to create a miniaturised and fully integrated optical biosensing platform. The presented self-aligned on-chip optical components offer an efficient means to direct excitation light within microfluidics and to directly couple light from a LED source. The device has been used in conjunction with a miniaturised and bespoke fluorescence detection platform to create a complete, palm sized system (≈60 × 80 × 60 mm) capable of performing fluoro-immunoassays. The system has been applied to the detection of cardiac Troponin I, one of the gold standard biomarkers for the diagnosis of acute myocardial infarction, achieving a lower detection limit of 0.08 ng/ml, which is at the threshold of clinically applicable concentrations. The portable nature of the complete system and the biomarker detection capabilities demonstrate the potential of the devised instrumentation for use as a medical diagnostics device at the point of care. 相似文献
189.
Marc R. Portus Peter J. Sinclair Stephen T. Burke David J.A. Moore Patrick J. Farhart 《Journal of sports sciences》2013,31(12):999-1011
The aims of this study were to determine the influence of an 8-over spell on cricket fast bowling technique and performance (speed and accuracy), and to establish the relationship of selected physical capacities with technique and performance during an 8-over spell. Fourteen first-grade fast bowlers with a mean age of 23 years participated in the study. Physical capacities assessed were abdominal strength, trunk stability, selected girth and skinfold measures. During the delivery stride, bowlers were filmed from an overhead and lateral perspective (50 Hz) to obtain two-dimensional data for transverse plane shoulder alignment and sagittal plane knee joint angle respectively. Ball speed was measured by a radar gun and accuracy by the impact point of each delivery on a zoned scoring target at the batter's stumps. Shoulder counter-rotation did not change significantly between overs 2 and 8 for all bowlers, but was significantly related to a more front-on shoulder orientation at back foot impact. When the front-on fast bowlers ( n = 5) were isolated for analysis, shoulder counter-rotation increased significantly between overs 2 and 8. Ball speed remained constant while accuracy showed some non-significant variation during the spell. Shoulder counter-rotation was significantly related to accuracy scores during the second half of the 8-over spell. Chest girth and composition and body composition were significantly related to ball release speed at various times during the spell. 相似文献
190.
Smetana JG Rote WM Jambon M Tasopoulos-Chan M Villalobos M Comer J 《Child development》2012,83(2):683-696
Developmental trajectories and individual differences in 70 American middle‐income 2½‐ to 4‐year olds’ moral judgments were examined 3 times across 1 year using latent growth modeling. At Wave 1, children distinguished hypothetical moral from conventional transgressions on all criteria, but only older preschoolers did so when rating deserved punishment. Children’s understanding of moral transgressions as wrong independent of authority grew over time. Greater surgency and effortful control were both associated with a better understanding of moral generalizability. Children higher in effortful control also grew more slowly in understanding that moral rules are not alterable and that moral transgressions are wrong independent of rules. Girls demonstrated sharper increases across time than boys in understanding the nonalterability of moral rules. 相似文献