A toy model that predicts the qualitative role of bar bend in a push jerk     

Aaron Santos  Norman E. Meltzer 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):345-359

In this work, we describe a simple coarse-grained model of a barbell that can be used to determine the qualitative role of bar bend during a jerk. In simulations of this model, we observed a narrow time window during which the lifter can leverage the elasticity of the bar in order to lift the weight to a maximal height. This time window shifted to later times as the weight was increased. In addition, we found that the optimal time to initiate the drive was strongly correlated with the time at which the bar had reached a maximum upward velocity after recoiling. By isolating the effect of the bar, we obtained a generalized strategy for lifting heavy weight in the jerk.  相似文献   

Is passive drag dependent on the interaction of kayak design and paddler weight in flat-water kayaking?     

Beatriz B. Gomes  Filipe A.V. Conceição  David R. Pendergast  Ross H. Sanders  Mário A.P. Vaz  João Paulo Vilas-Boas 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):394-403

Abstract

Drag is one of the major factors that influences kayaking performance. To focus on the drag of the kayak’s hull shape and the paddlers’ weight per se, the passive drag (D_p) was measured on a flat-water sprint course for one paddler with added weights. D_p was measured by an electromechanical towing device using a load cell, at incremental and constant velocities from 2.78 to 5.56 m/s. Three kayaks of different sizes and shapes (Nelo® K1 Quattro-M, ML, and L) were used and the paddlers’ body weight was adjusted with weights so the total paddler weight in the kayak was 65, 75, and 85 kg. The mean D_p increased by the power function of D = kvⁿ (mean R² = .990; SD .006). The D_p went from 21.37?±?1.29 N at 2.78 m/s to 89.32?±?6.43 N at 5.56 m/s. For the two lighter weighted kayaks (65 and 75 kg), the lowest D_p was observed with different kayak sizes (M, ML, or L) depending on the target velocity. The manufacturers suggest that paddlers should select a kayak size according to their body weight to minimise drag; however, the results of this study suggest that target velocities, and thus competition distance should also be factored into kayak selection.  相似文献   

The importance of transference and countertransference in Munchausen Syndrome by Proxy     

Pompili M  Mancinelli I  Girardi P  Ruberto A  Tatarelli R 《Child abuse & neglect》2003,27(4):353-355

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Inverted classroom teaching in the first-year design studio,a case study     

Maria Elisa Navarro Morales  Roberto Londoño 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(5):2651-2666

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Heat and Kinetic Theory in 19th-Century Physics Textbooks: The Case of Spain     

Vaquero  Joseb M.  Santos  Andrebs 《Science & Education》2001,10(3):307-319

Spain was a scientifically backward country in the early 19th century. The causes were various political events, the War of Independence, and the reignof Fernando VII. The introduction of contemporary physics into textbooks was thereforea slow process. An analysis of the contents of 19th-century Spanish textbooks is presented here, centred on imponderable fluids, the concept of energy, the mechanicaltheory of heat, and the kinetic theory of gases.  相似文献   

Learning design and learning analytics in mobile and ubiquitous learning: A systematic review     

Gerti Pishtari  María J. Rodríguez-Triana  Edna M. Sarmiento-Márquez  Mar Pérez-Sanagustín  Adolfo Ruiz-Calleja  Patricia Santos  Luis P. Prieto  Sergio Serrano-Iglesias  Terje Väljataga 《British journal of educational technology : journal of the Council for Educational Technology》2020,51(4):1078-1100

Mobile and Ubiquitous Learning (m/u-learning) are finding an increasing adoption in education. They are often distinguished by hybrid learning environments that encompass elements of formal and informal learning, in activities that happen in distributed settings (indoors and outdoors), across physical and virtual spaces. Despite their purported benefits, these environments imply additional complexity in the design, monitoring and evaluation of learning activities. The research literature on learning design (LD) and learning analytics (LA) has started to deal with these issues. This paper presents a systematic literature review of LD and LA, in m/u-learning. Apart from providing an overview of the current research in the field, this review elicits elements of common ground between both communities, as shown by the similar learning contexts and complementary research contributions, and based on the research gaps, proposes to: address m/u-learning beyond higher education settings, reinforce the connection between physical and virtual learning spaces, and more systematically align LD and LA processes.  相似文献   

The development of clinical reasoning skills: A major objective of the anatomy course     

Rodrigo E. Elizondo‐Omaña  Santos Guzmán López 《Anatomical sciences education》2008,1(6):267-268

Traditional medical school curricula have made a clear demarcation between the basic biomedical sciences and the clinical years. It is our view that a comprehensive medical education necessarily involves an increased correlation between basic science knowledge and its clinical applications. A basic anatomy course should have two main objectives: for the student to successfully gain a solid knowledge base of human anatomy and to develop and hone clinical reasoning skills. In a basic anatomy course, clinical case discussions based on underlying anatomic anomalies or abnormalities are the major means to teach students clinical reasoning skills. By identifying, classifying, and analyzing the clinical data given, a student learns to methodically approach a clinical case and formulate plausible diagnoses. Practicing and perfecting clinical problem‐solving skills should be a major objective of the anatomy curriculum. Such clinical reasoning skills are indeed crucial for the successful and expert practice of medicine. Anat Sci Ed 1:267–268, 2008. © 2008 American Association of Anatomists.  相似文献   

Hybrid Deterministic Views About Genes in Biology Textbooks: A Key Problem in Genetics Teaching     

Vanessa Carvalho dos Santos  Leyla Mariane Joaquim  Charbel Ni?o El-Hani 《Science & Education》2012,21(4):543-578

A major source of difficulties in promoting students’ understanding of genetics lies in the presentation of gene concepts and models in an inconsistent and largely ahistorical manner, merely amalgamated in hybrid views, as if they constituted linear developments, instead of being built for different purposes and employed in specific contexts. In this paper, we report the results of a study about how textbooks can provide the grounds for the students’ construction of such hybrid views about genes. These views are a key problem in genetics teaching, because they make it more difficult that students properly understand this central biological concept and strengthen genetic deterministic ideas, which characterize a widespread discourse about genes in the public opinion. We analyzed 18 textbooks using categorical content analysis, employing categories derived from the literature addressing the historical development of gene models and concepts. Our findings indicate that the analyzed textbooks do convey hybrid views about genes, with no correspondence to scientific models related to this biological concept. These views reinforce genetic deterministic discourses and may lead students to serious misunderstandings about the nature of genes and their role in living systems, with consequences to future learning about genetics.  相似文献   

History and Nature of Science in High School: Building Up Parameters to Guide Educational Materials and Strategies     

Thaís Cyrino de Mello Forato  Roberto de Andrade Martins  Maurício Pietrocola 《Science & Education》2012,21(5):657-682

This article presents the main results of a research examining the didactic transposition of history and philosophy of science in high school level. The adaptation of history of science to this particular level, addressing some aspects of the nature of science aiming at the students’ critical engagement, was analyzed by examining both the historiographic requirements of history of science and the pedagogical recommendations of science teaching. The research included the elaboration of a pilot course on the history of optics, with historical texts and educational activities, and its application in a high school. We used three episodes of the history of optics, addressing some epistemological points, especially criticizing the naive empirical-inductive view of science. It was possible to identify a series of obstacles in using history of science and conveying philosophical views. Their analysis resulted in devising strategies to surmount or to circumvent them. We implemented those strategies in the classroom and analyzed the data that was obtained. As a result, we substantiated several of our proposals and found that some solutions require improvement. We suggest some generalizations, which can be understood as initial parameters for guiding the use of history and philosophy of science in science teaching. We used a qualitative methodology of educational research to plan, to collect and to analyze the data, examining the interaction between students, teacher and knowledge.  相似文献   

Intellectual deficits in Brazilian victimized children and adolescents: A psychosocial problem?     

PA de Oliveira  GK Scarpari  B Dos Santos  S Scivoletto 《Child abuse & neglect》2012,36(7-8):608-610

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