基于业绩表现:系统设计复杂学习的十大步骤

现代教学理论倾向于把完成现实生活任务作为学习的动力(Clark ＆ Estes，1999；van Merrieenboer ＆ Kirschner，2001)。这些理论普遍认为，现实生活任务有助于学生综合运用知识、技能以及态度，以有效完成任务；给学生创设了掌握相关子技能的机会，以便经整合后能够完成复杂学习任务；并最终使学     

A microfluidic model to study fluid dynamics of mucus plug rupture in small lung airways

Fluid dynamics of mucus plug rupture is important to understand mucus clearance in lung airways and potential effects of mucus plug rupture on epithelial cells at lung airway walls. We established a microfluidic model to study mucus plug rupture in a collapsed airway of the 12th generation. Mucus plugs were simulated using Carbopol 940 (C940) gels at concentrations of 0.15%, 0.2%, 0.25%, and 0.3%, which have non-Newtonian properties close to healthy and diseased lung mucus. The airway was modeled with a polydimethylsiloxane microfluidic channel. Plug motion was driven by pressurized air. Global strain rates and shear stress were defined to quantitatively describe plug deformation and rupture. Results show that a plug needs to overcome yield stress before deformation and rupture. The plug takes relatively long time to yield at the high Bingham number. Plug length shortening is the more significant deformation than shearing at gel concentration higher than 0.15%. Although strain rates increase dramatically at rupture, the transient shear stress drops due to the shear-thinning effect of the C940 gels. Dimensionless time-averaged shear stress, T_xy, linearly increases from 3.7 to 5.6 times the Bingham number as the Bingham number varies from 0.018 to 0.1. The dimensionless time-averaged shear rate simply equals to T_xy/2. In dimension, shear stress magnitude is about one order lower than the pressure drop, and one order higher than yield stress. Mucus with high yield stress leads to high shear stress, and therefore would be more likely to cause epithelial cell damage. Crackling sounds produced with plug rupture might be more detectable for gels with higher concentration.     

Beyond plagiarism: Ethical misconduct in scientific and technical publishing

Ethical misconduct among scholars’whether plagiarism, data fabrication, data misrepresentation, or other forms of dishonesty’is on the rise, and increasingly in the public spotlight. Marcel LaFollette describes the context in which misconduct takes place, contrasting the nature of the scientific community before and after World War II. In the 1980s, the federal government facilitates, funds, and scrutinizes scientific research far more extensively than ever before. Increased political concern, LaFollette argues, will have far-reaching implications for scientists and their publishers. Marcel Chotkowski LaFollette is assistant professor, Massachusetts Institute of Technology, and visiting scholar, National Museum of American History, Smithsonian Institution. She is the former editor ofScience, Technology & Human Values and is currently writing a book on ethical misconduct in research communication. This article was prepared with support from the National Science Foundation under grant RII-8409904 “The Ethical Problems Raised by Fraud in Science and Engineering Publishing”.     

Die 1960er Jahre als Formationsphase von modernem Doping und Anti-Doping

Many contemporary forms of doping and anti-doping developed in the 1960s regarding substances, social perception, doping and anti-doping strategies and actors. The first significant steps towards regulation were made during this period. Anti-doping in West Germany was based on the principle of partnership between sport and state. However, it was not a specifically German solution but in line with the common anti-doping strategies of most other European countries. At the same time limits and obstacles of anti-doping became apparent.     

Physiologisch-metabolische Aspekte von Langzeit-Ausdauertests im Schulsport

From the perspective of preventive medicine and learning physiology it is important to introduce children and young people to effective aerobic endurance training. In the field study presented, boys and girls of school years 6, 8, 10 and 12 underwent 3 running tests of 12, 20 and 30 min duration and were tested for lactate concentration, heart rate and rate of perceived exertion (RPE). The physiological metabolic parameters were compared and recommendations for an appropriate long-term endurance test for school sport were given depending on the results. The 12 min running test provoked a higher average lactate concentration (5.3-10.9 mmol/l lactate) in both sexes of all school years than the 2 longer running tests. The average lactate concentrations, however, may be evaluated as quite harmless in school sport provided there is adequate preparation. The longer running tests also require sufficient preparation as they cause average lactate concentrations of approximately 4-8.5 mmol/l and obviously higher demands for volitional properties than shorter running tests. The 20 min running test can be considered as an alternative to the Cooper test (12 min running test): lactate concentrations in blood are between 18.5 % and 23?% lower on average and heart rates and RPE after the test are only slightly higher.     

Implementation Effects of a Program for the Training of Coaching Skills with School Principals∗

In this study, the implementation effects of a program for the training of coaching skills to Dutch primary school principals are described. Coaching is a form of in‐class support intended to provide teachers with feedback on their own functioning, and thereby to stimulate self‐reflection and self‐analysis in order to improve instructional effectiveness. To assist school principals in their attempts to coach teachers, a training program was designed and evaluated. Based on the pre‐ and post‐training ratings of coaching conferences, a significant treatment effect was found for the coaching skills concerned with the development of autonomy (empowerment), feedback, and agreement on classroom observational goals. The pre‐ and post‐training ratings from the coached teachers themselves showed a significant treatment effect for the coaching skills concerned with the development of improvement plans. Although the training provided for the school principals was directed at the coaching functions of consulting and confronting, the majority of the school principals conducted coaching conferences that emphasized predominantly the function of consulting.