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941.
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
942.
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
943.
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
944.
Veronica Macchi Andrea Porzionato Carla Stecco Cesare Tiengo Anna Parenti Adriano Cestrone Raffaele De Caro 《Anatomical sciences education》2011,4(3)
Medical Gross Anatomy lecture at the University of Padova, Italy. Gross Anatomy at the University of Padova is taught utilizing both traditional and technological resources, which are integrated with practical laboratory exercises (mainly on plastic models and plastinated specimens) as well as radiological anatomy. In this issue of ASE, Dr. Veronica Macchi and her colleagues from the Department of Human Anatomy and Physiology at the University of Padova discuss an innovative pilot project with their University Hospital in which they obtain body parts removed from patients during surgical procedures and utilize them for gross anatomy education. The cover photograph shows one of the co‐authors of this paper, Professor Raffaele De Caro and his students, performing dissection of the distal forearm and hand in the anatomy lecture theater at the University of Padova. 相似文献
945.
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
946.
947.
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
948.
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
949.
Robert B. Anderson Julius A. Marshall Andrea L’Afflitto 《Journal of The Franklin Institute》2021,358(12):6281-6308
In classical model reference adaptive control (MRAC), the adaptive rates must be tuned to meet multiple competing objectives. Large adaptive rates guarantee rapid convergence of the trajectory tracking error to zero. However, large adaptive rates may also induce saturation of the actuators and excessive overshoots of the closed-loop system’s trajectory tracking error. Conversely, low adaptive rates may produce unsatisfactory trajectory tracking performances. To overcome these limitations, in the classical MRAC framework, the adaptive rates must be tuned through an iterative process. Alternative approaches require to modify the plant’s reference model or the reference command input. This paper presents the first MRAC laws for nonlinear dynamical systems affected by matched and parametric uncertainties that constrain both the closed-loop system’s trajectory tracking error and the control input at all times within user-defined bounds, and enforce a user-defined rate of convergence on the trajectory tracking error. By applying the proposed MRAC laws, the adaptive rates can be set arbitrarily large and both the plant’s reference model and the reference command input can be chosen arbitrarily. The user-defined rate of convergence of the closed-loop plant’s trajectory is enforced by introducing a user-defined auxiliary reference model, which converges to the trajectory tracking error obtained by applying the classical MRAC laws before its transient dynamics has decayed, and steering the trajectory tracking error to the auxiliary reference model at a rate of convergence that is higher than the rate of convergence of the plant’s reference model. The ability of the proposed MRAC laws to prescribe the performance of the closed-loop system’s trajectory tracking error and control input is guaranteed by barrier Lyapunov functions. Numerical simulations illustrate both the applicability of our theoretical results and their effectiveness compared to other techniques such as prescribed performance control, which allows to constrain both the rate of convergence and the maximum overshoot on the trajectory tracking error of uncertain systems. 相似文献
950.
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