家教“漫”镜头

把自己完完全全塞进被窝里,最好只露出来两个鼻孔呼吸。一旦进了被窝,身体不知不觉就变成蜷缩状。稍微动一下,就感觉背后在刮五级大风。如果说北方的冬天属于物理伤害,那么南方的冬天就是魔法攻击。在南方的卧室里,一旦躺下,十头牛也别想把人拉出来。     

Self-efficacy and the stages and processes of change associated with adopting and maintaining muscular fitness-promoting behaviors

The majority of physical activity initiatives have been directed toward promoting cardiorespiratory fitness and general health. Far less attention has been devoted to encouraging or understanding muscular fitness-promoting behaviors. The purpose of this study was to determine if constructs from the Transtheoretical Model, a contemporary behavior change framework, could be adapted and applied to the study of muscular fitness-promoting behaviors. Participants were 429 college students who completed measures of stage of change, the behavioral and cognitive processes of change, and self-efficacy. All measures were modified to relate specifically to muscular fitness-promoting behaviors. Two direct discriminant function analyses were performed, revealing that the behavioral processes of change and self-efficacy were the major correlates of the stages of change for muscular fitness-promoting behaviors.     

Anatomy as the backbone of an integrated first year medical curriculum: design and implementation

Morehouse School of Medicine chose to restructure its first year medical curriculum in 2005. The anatomy faculty had prior experience in integrating courses, stemming from the successful integration of individual anatomical sciences courses into a single course called Human Morphology. The integration process was expanded to include the other first year basic science courses (Biochemistry, Physiology, and Neurobiology) as we progressed toward an integrated curriculum. A team, consisting of the course directors, a curriculum coordinator, and the Associate Dean for Educational and Faculty Affairs, was assembled to build the new curriculum. For the initial phase, the original course titles were retained but the lecture order was reorganized around the Human Morphology topic sequence. The material from all four courses was organized into four sequential units. Other curricular changes included placing laboratories and lectures more consistently in the daily routine, reducing lecture time from 120 to 90 minute blocks, eliminating unnecessary duplication of content, and increasing the amount of independent study time. Examinations were constructed to include questions from all courses on a single test, reducing the number of examination days in each block from three to one. The entire restructuring process took two years to complete, and the revised curriculum was implemented for the students entering in 2007. The outcomes of the restructured curriculum include a reduction in the number of contact hours by 28%, higher or equivalent subject examination average scores, enhanced student satisfaction, and a first year curriculum team better prepared to move forward with future integration.     

Factors associated with transitional shifts in college students' physical activity behavior

The Transtheoretical Model (Prochaska & Marcus, 1994) has been widely used as a framework for understanding exercise behavior change. The purpose of this study was to clarify equivocal research findings reported for model predictions when examining stage movement over time rather than static stages and to provide some evidence of the construct validity of transitional stages. Participants were female (n = 285) and male (n = 243) undergraduates (M age = 19.9 years, SD = 2.7) who completed previously validated questionnaires twice, separated by 9 weeks, that assessed stage of change, exercise behavior, processes of change, pros and cons of exercise, and exercise self-efficacy. Participants were classified into one of five transitional shift groups based on their responses at baseline and follow up: (a) stable sedentary, (b) stable active, (c) activity adopters, (d) activity relapsers, and (e) perpetual preparers. Results of a 5 (group) x 2 (time) repeated measures (RM) analysis of variance (ANOVA) examining exercise behavior revealed a significant interaction (p < .001) and supported transitional stage classification, with activity adopters and stable actives increasing exercise over time and relapsers decreasing activity. Separate 5 (group) x 2 (time) RM ANOVAs examining model constructs revealed no significant interaction for cognitive processes of change; however, activity adopters and stable actives reported significant (p < .01) increases in the use of behavioral processes over time, while only the activity relapsers and perpetual preparers reported decreases. Activity relapsers also reported significant (p < .05) decreases in the pros of exercise. No significant interactions were found for the cons of exercise behavior. Unlike findings reported in cross-sectional studies, increases in self-efficacy did not accompany increases in exercise stage. The findings strongly support examination of stage movement classifications rather than static stages, as these transitions provide greater insight into the mechanisms of exercise behavior change.     

Contributions of joint rotations to racquet speed in the tennis serve

The purpose of this study was to measure the contributions of the motions of body segments and joints to racquet head speed during the tennis serve. Nine experienced male players were studied using three-dimensional film analysis. Upper arm twist orientations were calculated with two alternative methods using joint centres and skin-attached markers. The results showed that skin-attached markers could not be used to calculate accurate upper arm twist orientations due to skin movement, and that the use of joint centres produced errors of more than 20 degrees in the upper arm twist orientation when the computed elbow flexion/extension angle exceeded 135 degrees in the final 0.03 s before impact. When there were large errors in the upper arm twist orientation, it was impossible to obtain accurate data for shoulder or elbow joint rotations about any axis. Considering only the contributors that could be measured within our standards of acceptable error, the approximate sequential order of main contributors to racquet speed between maximum knee flexion and impact was: shoulder external rotation, wrist extension, twist rotation of the lower trunk, twist rotation of the upper trunk relative to the lower trunk, shoulder abduction, elbow extension, ulnar deviation rotation, a second twist rotation of the upper trunk relative to the lower trunk, and wrist flexion. The elbow extension and wrist flexion contributions were especially large. Forearm pronation made a brief negative contribution. Computed contributions of shoulder internal rotation, elbow extension and forearm pronation within the final 0.03 s before impact were questionable due to the large degree of elbow extension. Near impact, the combined contribution of shoulder flexion/extension and abduction/adduction rotations to racquet speed was negligible.     

Facilitating long-term changes in student approaches to learning science

Undergraduates entering science curricula differ greatly in individual starting points and learning needs. The fast pace, high enrollment, and high stakes of introductory science courses, however, limit students' opportunities to self-assess and modify learning strategies. The University of Washington's Biology Fellows Program (BFP) intervenes through a 20-session, premajors course that introduces students to the rigor expected of bioscience majors and assists their development as science learners. This study uses quantitative and qualitative approaches to assess whether the 2007-2009 BFP achieved its desired short- and long-term impacts on student learning. Adjusting for differences in students' high school grade point average and Scholastic Aptitude Test scores, we found that participation in the BFP was associated with higher grades in two subsequent gateway biology courses, across multiple quarters and instructors. Two to 4 yr after participating in the program, students attributed changes in how they approached learning science to BFP participation. They reported having learned to "think like a scientist" and to value active-learning strategies and learning communities. In addition, they reported having developed a sense of belonging in bioscience communities. The achievement of long-term impacts for a short-term instructional investment suggests a practical means to prepare diverse students for the rigors of science curricula.     

A hospital-based patient and family education center: if you build it, will they come?

Librarians located in a 560-bed, inner city academic medical center with 25,000?+ admissions per year planned and opened a Patient and Family Education Center (PFEC) in the lobby of a new patient care pavilion. A review of use in the first 19 months revealed that expected needs were being met while a variety of unexpected needs were identified. Ongoing use continues to be monitored by a detailed log of patron visits maintained by library staff. This article describes the evolution of the Patient and Family Education Center, outreach to the hospital community, and plans for the future.     

A simple classroom teaching technique to help students understand Michaelis-Menten kinetics

A new, simple classroom technique helps cell biology students understand principles of Michaelis-Menten enzyme kinetics. A student mimics the enzyme and the student's hand represents the enzyme's active site. The catalytic event is the transfer of marbles (substrate molecules) by hand from one plastic container to another. As predicted, increases in marble concentration increase the number of marbles transferred per unit time (initial rate, V(0)) until the turnover number becomes rate limiting and V(0) approaches the maximum velocity (V(max)), as described by the Michaelis-Menten equation. With this demonstration, students visualize an important concept: the turnover number is constant and independent of marble concentration. A student assessment of this exercise showed that it helped students visualize the turnover number and V(max) but not K(m), the marble concentration at which V(0) is one-half V(max). To address the concept of K(m), we use supplemental laboratory and lecture exercises. This exercise with plastic containers and marbles is equally suited to demonstrate the kinetics of carrier-mediated membrane transport. We conclude that this exercise helps students visualize the turnover number and V(max) and gives students important insights into the kinetic parameters used to characterize the catalytic activity of enzymes and membrane transporters.