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991.
The present work investigates the relations between amplitude and type of collaboration (intramural, extramural domestic or international) and output of specialized versus diversified research. By specialized or diversified research, we mean within or beyond the author’s dominant research topic. The field of observation is the scientific production over five years from about 23,500 academics. The analyses are conducted at the aggregate and disciplinary level. The results lead to the conclusion that in general, the output of diversified research is no more frequently the fruit of collaboration than is specialized research. At the level of the particular collaboration types, international collaborations weakly underlie the specialized kind of research output; on the contrary, extramural domestic and intramural collaborations are weakly associated with diversified research. While the weakness of association remains, exceptions are observed at the level of the individual disciplines. 相似文献
992.
Tara M. Mortensen Brian P. McDermott Khadija Ejaz Daniel D. Haun 《Journalism Practice》2019,13(5):576-591
This study is the first to inquire about the factors that influence people’s willingness to allow professional photojournalists to tell their stories through the medium of the photo essay. Guided by Self-Disclosure Theory, in-depth interviews were conducted with the subjects of 15 peer-judged award-winning photo essays. These were drawn from the multiple picture categories of the National Press Photographers Association (NPPA) Monthly Clip Contest, the annual NPPA Best of Photojournalism Contest, and the annual World Press Photo Contest between 2013 and 2017. The topics of the photo essays were sensitive in nature. Analysis reveals support and appreciation amongst photo-essay subjects for the profession of photojournalism. Motivations derived from the sensitivity and professionalism with which each interviewee was initially approached, a need to tell a different side of the story, a desire to inspire others or invoke change, and the memory-keeping and permanence afforded through published professional photojournalism. 相似文献
993.
Commonly used technical anatomy and physiology (A&P) terms are predominantly rooted in Latin and Greek vocabulary, so it is commonly inferred that a solid grounding in Latin and Greek roots of medical terminology will improve student learning in anatomy and related disciplines. This study examines the association of etymological knowledge of A&P terms and A&P course performance among 446 undergraduates in their first semester of the study of human gross anatomy and physiology, with a more detailed analysis of the characteristics of 52 students who filled out surveys about their prior knowledge and experiences related to medicine or anatomy. In both data sets, there was only a weak positive correlation between the performance on a quiz of Latin and Greek medical terms and the students' performance on regular assignments. The presumption that familiarity with Latin and Greek word roots has a strong influence on successful learning of anatomy is not supported by these data. Future research should address whether or not there are particular skills associated with using etymological knowledge in improving A&P course performance. 相似文献
994.
Today's doctoral programs continue to prepare students for a traditional academic career path despite the inadequate supply of research-focused faculty positions. We advocate for a broader doctoral curriculum that prepares trainees for a wide range of science-related career paths. In support of this argument, we describe data from our survey of doctoral students in the basic biomedical sciences at University of California, San Francisco (UCSF). Midway through graduate training, UCSF students are already considering a broad range of career options, with one-third intending to pursue a non-research career path. To better support this branching career pipeline, we recommend that national standards for training and mentoring include emphasis on career planning and professional skills development to ensure the success of PhD-level scientists as they contribute to a broadly defined global scientific enterprise. 相似文献
995.
Haubert LM Way D DePhilip R Tam M Bishop J Jones K Moffatt-Bruce SD 《Anatomical sciences education》2011,4(4):182-189
Despite extensive experience teaching residents, surgeons are an untapped resource for educating medical students. We hypothesized that by involving surgeons as teachers earlier in the medical school curriculum, medical students' interest in surgery will increase and their opinions of surgeons will improve. Five programs designed to involve surgeons as educators in the medical school curriculum were implemented. The first program, started in 2008, introduced surgical faculty into the first-year medical student anatomy dissection laboratories. Other programs initiated in 2008 included: Surgical Clinical Correlates in Anatomy, which involved faculty teaching through cadaver surgery; Clinical Pathologic Conferences in Anatomy, a surgeon-led conference based on clinical cases; and a women's faculty-student mentorship program. Table Rounds, a surgeon-led anatomy review that used clinical scenarios to quiz students was begun in 2009. All five programs were successfully integrated into the medical school curriculum. While student opinion of surgeons as educators improved, there were no significant changes in student interest in surgery as a career nor change in performance on written examinations over the Anatomy content covered by the surgeons. Surgical faculty and trainees can be integrated into the medical school curriculum. Involving surgeons as educators earlier in the medical school curriculum may have longer term effects than could be observed in this study. At a minimum, the experience improved student opinion of surgeons as educators. 相似文献
996.
997.
An increasing number of instructors are seeking to provide students with online anatomy resources. Many researchers have attempted to identify associations between resource use and student learning but few studies discuss the importance of usability testing in resource design and modification. Usability testing provides information about ease of use and resource flexibility and indicates navigational issues that contribute to extraneous cognitive load for the user. An example of usability testing for modification of an online anatomy resource called the "Virtual Lab" is presented. Usability testing was used to determine whether increased content would impair navigation through the interface. Subjects with varying levels of experience with anatomy content were recruited to assess efficiency and effectiveness (defined by usability standards) of the original resource and of the redesigned resource. Comparisons between usability evaluation of the original "Virtual Lab" (OVL) and of the redesigned "Virtual Lab" (RVL) revealed that subjects were better able to successfully complete tasks using the RVL than they were with the OVL. Results also demonstrated that subjects did not take significantly more time to successfully complete tasks with the RVL. Additionally, usability testing revealed that subjects were able to successfully complete tasks using the RVL regardless of whether they possessed prior experience with anatomy content or not. Results of this study suggest that the modified resource is more effective for users. The example presented here underscores the need for usability testing prior to resource implementation and whenever significant changes are made to a resource interface. 相似文献
998.
Weiwei Yang Jiejunyi Liang Jue Yang Paul D. Walker Nong Zhang 《Journal of The Franklin Institute》2021,358(2):1214-1239
An hybrid uninterrupted multi-speed transmission (HUMST), based on the integration of a planetary gear set and a 3-speed automatic manual transmission (3-AMT), is developed to satisfy the specific performance indexes of mining trucks. The power-split device can alleviate and eliminate the inherent torque interruption of the 3-AMT during gear shift by implementing the designed cooperative shift control strategy which is optimized by quadratic performance index. In order to achieve fast torque coordination while guaranteeing the driving comfort performance, the torque profiles of the power split device and the traction motor are optimized by Linear-quadratic regulator (LQR) algorithm. Dynamic programming (DP) is implemented as a benchmark to demonstrate the maximum fuel efficiency of the proposed HUMST. Because of the high computational cost of optimal control strategies such as DP, an improved real-time control strategy (IRTCS) using modified Gaussian distribution function is proposed to significantly reduce the computing load. As efficiency-oriented energy control strategy would result in frequent gear shifts, to achieve a desirable tradeoff between the overall efficiency and the shift stability, multi-objective genetic algorithm (MGA) is integrated to optimize the overall performance. The detail mathematical and dynamic model shows that the proposed shifting strategy with LQR can effectively suppress shift jerk, and the proposed IRTCS with MGA can reduce shift frequency by 70.78% to improve the drivability, only sacrificing 4.86% of overall efficiency compared to that of DP. 相似文献
999.
Reyes GF Dickin DC Crusat NJ Dolny DG 《Sports biomechanics / International Society of Biomechanics in Sports》2011,10(4):280-293
The purpose of this study was to evaluate the effects of whole-body vibration (WBV) on the muscle recruitment of selected upper and lower body muscles during the baseball swing. Participants were recreationally trained males (n = 16, 22 +/- 2 years, 181.4 +/- 7.4 cm, 84.7 +/- 9.0 kg), with previous baseball experience. Subjects participated in three randomized sessions on separate days, consisting of three sets of five swings offa hitting tee. Exercises (upper and lower body dynamic and static movements) with or without WBVexposure were performed between swing sets. During each swing, the gastrocnemius, biceps femoris, gluteus maximus, pectoralis major, latissimus dorsi, and triceps brachii were evaluated for electromyographic (EMG) activity. EMG values were normalized to EMG measured during maximal voluntary isometric contraction. Statistical analysis revealed no significant differences in EMG activity across the three treatments. In addition, the results displayed a specific muscle recruitment order during the swing, starting with the lower body followed by the upper body muscles. This study was the first to report the recruitment order during the baseball swing. Although acute exposure to WBV did not significantly alter the muscle recruitment, these results may prove useful for practitioners looking to enhance baseball swing performance. 相似文献
1000.
排球运动由于本身的竞技与技术特点,在训练、比赛、教学中非常容易造成损伤。文章运用文献资料发、问卷调查法、数理统计法、逻辑分析法等研究方法,对山西大学体育学院排球专选课学生膝关节损伤的状况进行调查分析,同时提出预防膝关节损伤的措施,以期为防治排球教学过程中的膝关节损伤提供参考依据。 相似文献