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71.
Objective:The authors used an assessment rubric to measure medical students'' improvement in question formulation skills following a brief evidence-based practice (EBP) training session conducted by a health sciences librarian.Method:In a quasi-experimental designed study, students were assessed using a rubric on their pre-instructional skills in formulating answerable EBP questions, based on a clinical scenario. Following their training, they were assessed using the same scenario and rubric. Student pre- and post-test scores were compared using a paired t-test.Results:Students demonstrated statistically significant improvement in their question formulation skills on their post-instructional assessments. The average score for students on the pre-test was 45.5 (SD 11.1) and the average score on the post-test was 65.6 (SD 5.4) with an average increase of 20.1 points on the 70-point scale, p<0.001.Conclusion:The brief instructional session aided by the rubric improved students'' performance in question formulation skills.  相似文献   
72.
We report the Laser Induced Forward Transfer (LIFT) of antibodies from a liquid donor film onto paper receivers for application as point-of-care diagnostic sensors. To minimise the loss of functionality of the active biomolecules during transfer, a dynamic release layer was employed to shield the biomaterial from direct exposure to the pulsed laser source. Cellulose paper was chosen as the ideal receiver because of its inherent bio-compatibility, liquid transport properties, wide availability and low cost, all of which make it an efficient and suitable platform for point-of-care diagnostic sensors. Both enzyme-tagged and untagged IgG antibodies were LIFT-printed and their functionality was confirmed via a colorimetric enzyme-linked immunosorbent assay. Localisation of the printed antibodies was exhibited, which can allow the creation of complex 2-d patterns such as QR codes or letters for use in a final working device. Finally, a calibration curve was determined that related the intensity of the colour obtained to the concentration of active antibodies to enable quantitative assessment of the device performance. The motivation for this work was to implement a laser-based procedure for manufacturing low-cost, point-of-care diagnostic devices on paper.  相似文献   
73.
The discovery or re-construction of scientific explanations and understanding based on experience is a complex process, for which school learning often uses shortcuts. On the basis of the example of analyzing real seismic measurements, we propose a computer-facilitated collaborative learning scenario which meets many of the requirements for authentic learning, knowledge construction, and collaboration. The implementation of the learning environment called SeisModes is based on a general platform for supporting collaborative modeling activities. SeisModes provides a tool to allow students collaboratively learn about earthquakes and thus reduce the fears they might have concerning them. First formal evaluations showed the approach motivates students.  相似文献   
74.
In the social science literature, various motives for volunteering are discussed. However, so far little is known about the specific relationship between these motives and the time invested in voluntary work. Hypotheses derived from consumer goods theory concerning this association were examined. The results show (1) that altruistic motives increase the amount of engagement, and (2) that selfishly motivated volunteerism is an experience good.  相似文献   
75.
To determine the movement patterns and physiological demands of top-class soccer assistant referees, we performed computerized time-motion analysis and measured heart rate and blood lactate concentration in 15 assistant referees during 22 competitive matches in the top Danish league. To relate match performance to the physical capability of the assistant referees, they performed a 3 2 30 m sprint protocol before and after matches and a laboratory treadmill test within 3 weeks of the games. The mean total distance covered by the top-class assistant referees was 7.28 (range 5.78-8.16) km, of which 1.15 (0.86-1.44) km was high-intensity running and 1.16 (0.12-2.34) km was sideways running. The amount of high-intensity running during a game was correlated with performance of repeated sprints (r = 0.80, P ? 0.05). Mean heart rate was 137 (117-159) beats · min-1 , corresponding to 73% (60-88%) of maximal heart rate and 65% (53-80%) of maximal oxygen uptake. Blood lactate concentration was 4.7 (1.6-11.0) and 4.8 (1.1-13.7) mmol · l -1 after the first and second half, respectively. Sprinting performance was poorer (P ? 0.05) after than before the games. The peak distance to the offside line was greater (P ? 0.05) in the second than the first half (7 - 1 vs 5 - 0 m). Our results show that: (1) top-class assistant soccer refereeing is characterized by brief intense bouts of forward and sideways running interspersed with long periods of low activity; (2) top-class soccer assistant referees have moderate aerobic energy production during games with episodes of high aerobic and anaerobic energy turnover; (3) assistant referees' performance of repeated sprints correlates with the amount of high-intensity running performed in a game; and (4) sprint performance decreases towards the end of a game, which appears to affect assistant referees' ability to keep up with play.  相似文献   
76.
Abstract

Sport facilities are instrumental in keeping the population fit and healthy. Governments worldwide are thus engaged in devising policies, programs and projects for building such facilities, with the aim of providing citizens with opportunities for a healthy lifestyle. This feature is prominent in the Nordic countries, which have incorporated sport, leisure and physical activity into their universal welfare models. Understanding policies and politics for building sports facilities has therefore become a cornerstone in the understanding of conditions for sport and physical activity for all. In this paper, we investigate and compare the national structures for building and managing sports facilities in the Nordic countries, in order to add to the understanding of how policies and politics for building sport facilities can add to or hamper the sport-for-all ambitions salient in most of today’s western societies.  相似文献   
77.
Determination of amyloid β (Aβ) isoforms and in particular the proportion of the Aβ 1-42 isoform in cerebrospinal fluid (CSF) of patients suspected of Alzheimer's disease might help in early diagnosis and treatment of that illness. Due to the low concentration of Aβ peptides in biological fluids, a preconcentration step prior to the detection step is often necessary. This study utilized on-chip immunoprecipitation, known as micro-immunoprecipitation (μIP). The technique uses an immunosorbent (IS) consisting of magnetic beads coated with specific anti-Aβ antibodies organized into an affinity microcolumn by a magnetic field. Our goal was to thoroughly describe the critical steps in developing the IS, such as selecting the proper beads and anti-Aβ antibodies, as well as optimizing the immobilization technique and μIP protocol. The latter includes selecting optimal elution conditions. Furthermore, we demonstrate the efficiency of anti-Aβ IS for μIP and specific capture of 5 Aβ peptides under optimized conditions using various subsequent analytical methods, including matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), capillary electrophoresis, microchip electrophoresis, and immunoblotting. Synthetic Aβ peptides samples prepared in buffer and spiked in human CSF were analyzed. Finally, on-chip immunoprecipitation of Aβ peptides in human CSF sample was performed.  相似文献   
78.
Jens Bjerg 《Prospects》1994,24(1-2):21-35
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79.
To determine the movement patterns and physiological demands of top-class soccer assistant referees, we performed computerized time-motion analysis and measured heart rate and blood lactate concentration in 15 assistant referees during 22 competitive matches in the top Danish league. To relate match performance to the physical capability of the assistant referees, they performed a 3 x 30 m sprint protocol before and after matches and a laboratory treadmill test within 3 weeks of the games. The mean total distance covered by the top-class assistant referees was 7.28 (range 5.78-8.16) km, of which 1.15 (0.86-1.44) km was high-intensity running and 1.16 (0.12-2.34) km was sideways running. The amount of high-intensity running during a game was correlated with performance of repeated sprints (r = 0.80, P < 0.05). Mean heart rate was 137 (117-159) beats x min(-1), corresponding to 73% (60-88%) of maximal heart rate and 65% (53-80%) of maximal oxygen uptake. Blood lactate concentration was 4.7 (1.6-11.0) and 4.8 (1.1-13.7) mmol x 1(-1) after the first and second half, respectively. Sprinting performance was poorer (P < 0.05) after than before the games. The peak distance to the offside line was greater (P < 0.05) in the second than the first half (7 +/- 1 vs 5 +/- 0 m). Our results show that: (1) top-class assistant soccer refereeing is characterized by brief intense bouts of forward and sideways running interspersed with long periods of low activity; (2) top-class soccer assistant referees have moderate aerobic energy production during games with episodes of high aerobic and anaerobic energy turnover; (3) assistant referees' performance of repeated sprints correlates with the amount of high-intensity running performed in a game; and (4) sprint performance decreases towards the end of a game, which appears to affect assistant referees' ability to keep up with play.  相似文献   
80.
Die Sch?tzung des Aufwands für die Erstellung oder die überarbeitung von grossen Softwaresystemen stellt immer noch ein betr?chtliches Risiko dar. Dieses versch?rft sich noch weiter, wenn wie im vorliegenden Fall das Projekt auf Festpreisbasis, d.h. ohne M?glichkeit zu Budgetnachforderungen w?hrend des Projekts selbst, abzuwickeln ist. Dieser Beitrag beschreibt die Erfahrungen mit der Sch?tzung und vor allem der Nutzung der detailliert ermittelten Produktivit?tsmasse in einem grossen Konversionsprojekt, bei dem 350 Assembler-Programme aus dem Wertpapierbereich einer Bankorgansiation mit unver?nderter Funktionalit?t nach COBOL zu konvertieren waren. Dabei wurden w?hrend des Projekts die bereits vorliegenden Produktivit?tszahlen genutzt, um neben einer weiteren Optimierung der Verfahren und Abl?ufe auch die Sch?tzung bez. der noch zu bearbeitenden Arbeitspakete weiter zu verbessern. Es hat sich auch in diesem Projekt gezeigt, dass auch einfachere Sch?tzans?tze tragen, wenn sie denn auf den Erfahrungen der eigenen Projektorganisation basieren. Allgemeine algorithmische Ans?tze sind zwar als grober Anhaltspunkt brauchbar, ersetzen aber nicht die eigenen Zahlenbasen. Diese in jedem Projekt immer wieder konsequent und detailliert zu ermitteln, bleibt die vorrangige Aufgabe zur Unterstützung der Sch?tzung weiterer Projekte.  相似文献   
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