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161.
James Shedlock Michelle Frisque Steve Hunt Linda Walton Jonathan Handler Michael Gillam 《Journal of the Medical Library Association》2010,98(2):98-104
Question:
How can the user''s access to health information, especially full-text articles, be improved? The solution is building and evaluating the Health SmartLibrary (HSL).Setting:
The setting is the Galter Health Sciences Library, Feinberg School of Medicine, Northwestern University.Method:
The HSL was built on web-based personalization and customization tools: My E-Resources, Stay Current, Quick Search, and File Cabinet. Personalization and customization data were tracked to show user activity with these value-added, online services.Main Results:
Registration data indicated that users were receptive to personalized resource selection and that the automated application of specialty-based, personalized HSLs was more frequently adopted than manual customization by users. Those who did customize customized My E-Resources and Stay Current more often than Quick Search and File Cabinet. Most of those who customized did so only once.Conclusion:
Users did not always take advantage of the services designed to aid their library research experiences. When personalization is available at registration, users readily accepted it. Customization tools were used less frequently; however, more research is needed to determine why this was the case. 相似文献162.
In this paper, we present a microfluidic chip that is capable of measuring electrical conductance through gap junction channels in a 2-dimensional cell sheet. The chip utilizes a tri-stream laminar flow to create a non-conductive sucrose gap between the two conducting solutions so that electrical current can pass across the sucrose gap only through the cells. Using the chip, we tested the effect of a gap junction inhibitor, 2-APB, on the electrical coupling of connexin 43 (Cx43) gap junction channels in NRK-49F cells. We found that 2-APB reversibly blocks the conductivity in a dose-dependent manner. The tri-stream chip further allows us to simultaneously follow the conductance changes and dye diffusion in real time. We show that 2-APB affects both conductance and diffusion, supporting the interpretation that both sets of data reflect the same gap junction activity. The chip provides a generic platform to investigate gap junction properties and to screen drugs that may inhibit or potentiate gap junction transmission. 相似文献
163.
The purpose of the present study was to analyse the variability in clubhead presentation to the ball and the resulting ball impact location on the club face for a range of golfers of different ability. A total of 285 male and female participants hit multiple shots using one of four proprietary drivers. Self-reported handicap was used to quantify a participant's golfing ability. A bespoke motion capture system and user-written algorithms was used to track the clubhead just before and at impact, measuring clubhead speed, clubhead orientation, and impact location. A Doppler radar was used to measure golf ball speed. Generally, golfers of higher skill (lower handicap) generated increased clubhead speed and increased efficiency (ratio of ball speed to clubhead speed). Non-parametric statistical tests showed that low-handicap golfers exhibit significantly lower variability from shot to shot in clubhead speed, efficiency, impact location, attack angle, club path, and face angle compared with high-handicap golfers. 相似文献
164.
Angelos Stefanidis Guy Fitzgerald Steve Counsell 《International Journal of Information Management》2012
There is little conclusive evidence about the state of the IS curriculum in the UK. This paper presents the results of a detailed survey about the provision of Information Systems (IS) undergraduate degree courses in the UK using the newly developed IS 2010 curriculum guidelines as its basis. IS 2010 identifies three main categories of knowledge that underpin the essence of IS as an academic subject: IS Specific Knowledge and Skills, Domain Fundamentals and Foundational Knowledge and Skills. Our desire to offer a holistic and conclusive representation of the curriculum is supported by the development of an IS curriculum survey framework that caters for the mapping of every subject that populates the IS curricula of undergraduate degrees in the UK, including subjects that are generic or are derived from other hierarchical disciplines. 相似文献
165.
Betzler NF Monk SA Wallace ES Otto SR 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(2):223-238
The aim of this study was to quantify and explain the effect of shaft stiffness on the dynamics of golf drives. Twenty golfers performed swings with two clubs designed to differ only in shaft bending stiffness. Wrist kinematics and clubhead presentation to the ball were determined using optical motion capture systems in conjunction with a radar device for capturing ball speed, launch angle, and spin. Shaft stiffness had a marginally small effect on clubhead and ball speeds, which increased by 0.45% (p < 0.001) and 0.7% (p = 0.008), respectively, for the less stiff club. Two factors directly contributed to these increases: (i) a faster recovery of the lower flex shaft from lag to lead bending just before impact (p < 0.001); and (ii) an increase of 0.4% in angular velocity of the grip of the lower flex club at impact (p = 0.003). Unsurprisingly, decreases in shaft stiffness led to more shaft bending at the transition from backswing to downswing (p < 0.001). Contrary to previous research, lead bending at impact marginally increased for the stiffer shaft (p = 0.003). Overall, and taking effect sizes into account, the changes in shaft stiffness in isolation did not have a meaningful effect on the measured parameters, for the type of shaft investigated. 相似文献
166.
Over the last 20 years, states and provinces have become increasingly involved in the financing and administration of elementary and secondary education. Local school boards, however, still retain control over key aspects of the provision of education. Historically, these boards were organized at the community level so as to meet the wants of the local community. Today, states and provinces have become more interested in consolidating school boards and moving to a more centralized funding scheme. Do these changes result in improved student achievement? This paper attempts to answer these questions by examining the school board consolidation and funding changes instituted by the province of Ontario. We differentiate the effects of the policy changes based on observed differences in the school boards prior to consolidation. We show that students in previously high wealth school boards perform worse after the policy change compared to students in previously low wealth school boards. 相似文献
167.
168.
Recent developments in Nancy Cartwright's philosophy are examined, against the background of her earlier ideas. The examination is structured around two related problems for the interpretation of Cartwright; how to understand Cartwright's claim that we can see capacities in experiments, and the question of whether Cartwright is entitled to call herself an empiricist. It is argued that we should understand Cartwright as allowing that the seeing of capacities in experiments can incorporate an interpretive aspect. It is further argued that, although Cartwright is a long way from contemporary Humean empiricists, her views can be understood as falling within the broad empiricist tradition. In the process of addressing these issues the role of idealization in Cartwright's thought is explained. 相似文献
169.
In this study, we assessed the performance of trained senior (n = 6) and veteran (n = 6) cyclists (mean age 28 years, s = 3 and 57 years, s = 4 respectively). Each competitor completed two cycling tests, a ramped peak aerobic test and an indoor 16.1-km time-trial. The tests were performed using a Kingcycle ergometer with the cyclists riding their own bicycle fitted with an SRM powermeter. Power output, heart rate, and gas exchange variables were recorded continuously and blood lactate concentration [HLa] was assessed 3 min after the peak ramped test and at 2.5-min intervals during the time-trial. Peak values for power output (RMP(max)), heart rate (HR(peak)), oxygen uptake (VO2(peak)), and ventilation (V(Epeak)) attained during the ramped test were higher in the senior group (P < 0.05), whereas [HLa](peak), RER(peak), V(E): VO2(peak), and economy(peak) were similar between groups (P > 0.05). Time-trial values (mean for duration of race) for power output (W(TT)), heart rate (HR(TT)), VO2 (VO(2TT)), and V(E) (V(ETT)) were higher in the seniors (P < 0.05), but [HLa](TT), RER(TT), V(ETT): VO2(TT), and economy(TT) were similar between the groups (P > 0.05). Time-trial exercise intensity, expressed as %RMP(max), %HR(peak), % VO2(peak), and % V(Epeak), was similar (P > 0.05) for seniors and veterans (W(TT): 81%, s = 2 vs. 78%, s = 8; HR(TT): 96%, s = 4 vs. 94%, s = 4; VO2(TT): 92%, s = 4 vs. 95%, s = 10; V(ETT): 89%, s = 8 vs. 85%, s = 8, respectively). Overall, seniors attained higher absolute values for power output, heart rate, VO2, and V(E) but not blood lactate concentration, respiratory exchange ratio (RER), V(E): VO2, and economy. Veterans did not accommodate age-related declines in time trial performance by maintaining higher relative exercise intensity. 相似文献
170.
Kenny IC Wallace ES Otto SR 《Sports biomechanics / International Society of Biomechanics in Sports》2008,7(3):322-332
The aim of this study was to determine how shaft length affects golf driving performance. A range of drivers with lengths between 1.168 m and 1.270 m, representing lengths close to the 1.219 m limit imposed by R&A Rules Limited (2008), were assembled and evaluated. Clubhead and ball launch conditions and drive distance and accuracy were determined for seven category 1 golfers (handicaps 0.21 +/- 2.41) who performed shots on a purpose-built practice hole. As shaft length increased from 1.168 m to 1.270 m, initial ball velocity increased (+ 1.8 m/s, P < 0.01). Ball carry (+ 4.3 m, P = 0.152) also increased, although not significantly so. Furthermore, as shaft length increased, for all club comparisons there was no decrease in accuracy. Ball launch conditions of spin components and launch angle remained unaffected by shaft length. Launch angle increased (0.8 degree, F = 1.074, P = 0.362) as driver shaft length increased. Our results show that clubhead and ball velocity together with ball carry tended to increase with no loss of accuracy. 相似文献