Sex is for fun: IVF is for children     

Whelan J 《New scientist (1971)》2006,192(2574):42-45

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Strategic Planning: From Training to Performance Technology Within Three Years     

Karolyn A. Smalley  Sharon Inman  Mary Jo DeJong 《Performance Improvement Quarterly》1995,8(2):114-124

Many corporate Human Resource Development (HRD) department staff are type-cast as trainers. They have tried to become human performance technologists and have found it difficult to accomplish. This article describes how developing and implementing a set of strategic plans guided one HRD department through its evolution from delivering conventional training to delivering multiple performance improvement interventions. It will show how projects were selected, developed, and managed over a three-year period to meet the customer's critical business issues and the HRD department's strategic plan.  相似文献   

Embodied cognition as grounding for situatedness and context in mathematics education   总被引：1，自引：0，他引：1  

Rafael E. Núñez  Laurie D. Edwards  João Filipe Matos 《Educational Studies in Mathematics》1999,39(1-3):45-65

In this paper we analyze, from the perspective of 'Embodied Cognition', why learning and cognition are situated and context-dependent. We argue that the nature of situated learning and cognition cannot be fully understood by focusing only on social, cultural and contextual factors. These factors are themselves further situated and made comprehensible by the shared biology and fundamental bodily experiences of human beings. Thus cognition itself is embodied, and the bodily-grounded nature of cognition provides a foundation for social situatedness, entails a reconceptualization of cognition and mathematics itself, and has important consequences for mathematics education. After framing some theoretical notions of embodied cognition in the perspective of modern cognitive science, we analyze a case study – continuity of functions. We use conceptual metaphor theory to show how embodied cognition, while providing grounding for situatedness, also gives fruitful results in analyzing the cognitive difficulties underlying the understanding of continuity. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Does weight status influence associations between children's fundamental movement skills and physical activity?     

Hume C  Okely A  Bagley S  Telford A  Booth M  Crawford D  Salmon J 《Research quarterly for exercise and sport》2008,79(2):158-165

This study sought to determine whether weight status influences the association among children's fundamental movement skills (FMS) and physical activity (PA). Two hundred forty-eight children ages 9-12 years participated. Proficiency in three object-control skills and two locomotor skills was examined. Accelerometers objectively assessed physical activity. Body mass index was calculated to determine weight status. Correlations between physical activity and FMS proficiency were evident among boys and girls. No significant interaction was apparent when examining FMS proficiency scores, PA variables, and weight status. Future studies should examine a broader range of skills and types of activities to better characterize this relationship and to inform the promotion of movement skill proficiency and PA.  相似文献   

Muscle coordination,activation and kinematics of world-class and elite breaststroke swimmers during submaximal and maximal efforts     

Bjørn Harald Olstad  João Rocha Vaz  Christoph Zinner  Jan M.H. Cabri  Per-Ludvik Kjendlie 《Journal of sports sciences》2017,35(11):1107-1117

The aims of this study were to describe muscular activation patterns and kinematic variables during the complete stroke cycle (SC) and the different phases of breaststroke swimming at submaximal and maximal efforts. Surface electromyography (sEMG) was collected from eight muscles in nine elite swimmers; five females (age 20.3 ± 5.4 years; Fédération Internationale de Natation [FINA] points 815 ± 160) and four males (27.7 ± 7.1 years; FINA points 879 ± 151). Underwater cameras were used for 3D kinematic analysis with automatic motion tracking. The participants swam 25 m of breaststroke at 60%, 80% and 100% effort and each SC was divided into three phases: knee extension, knee extended and knee flexion. With increasing effort, the swimmers decreased their SC distance and increased their velocity and stroke rate. A decrease during the different phases was found for duration during knee extended and knee flexion, distance during knee extended and knee angle at the beginning of knee extension with increasing effort. Velocity increased for all phases. The mean activation pattern remained similar across the different effort levels, but the muscles showed longer activation periods relative to the SC and increased integrated sEMG (except trapezius) with increasing effort. The muscle activation patterns, muscular participation and kinematics assessed in this study with elite breaststroke swimmers contribute to a better understanding of the stroke and what occurs at different effort levels. This could be used as a reference for optimising breaststroke training to improve performance.  相似文献   

Acute and chronic effect of sodium bicarbonate ingestion on Wingate test performance: a systematic review and meta-analysis     

João Paulo Lopes-Silva  Reid Reale  Emerson Franchini 《Journal of sports sciences》2019,37(7):762-771

The aim of this study was to perform a systematic review and meta-analysis on the acute and chronic effects of sodium bicarbonate (NaHCO₃) ingestion on Wingate performance. Following a search through PubMed, Scopus and Web of Science, 9 studies were found meeting inclusion criteria (6 acute and 3 chronic). Random-effects meta-analysis of standardized mean difference (SMD) for peak and mean power was performed. Study quality was assessed using the QualSyst. Results of the meta-analysis showed that acute ingestion of NaHCO₃ did not improve Wingate test peak (weighted average effect size Hedges’s g = 0.02, 95%CI: – 0.19 to 0.23, P = 0.87) or mean power (weighted average effect size Hedges’s g = 0.15, 95%CI: ?0.06 to 0.36, P = 0.92). However, chronic ingestion of NaHCO₃ improved Wingate test peak (weighted average effect size Hedges’s g = 1.21, 95%CI: 0.83 to 1.42, P = 0.001) and mean power (weighted average effect size Hedges’s g = 1.26, 95%CI: 0.96 to 1.56, P = 0.001). Quality assessment of selected articles was classified as strong. This meta-analysis provides evidence that chronic, but not acute, ingestion of NaHCO₃ increases both Wingate test peak and mean power.  相似文献   

Predicting centre of mass horizontal speed in low to severe swimming intensities with linear and non-linear models     

Kelly de Jesus  Helon Vicente Hultmann Ayala  Leandro dos Santos Coelho  João Paulo Vilas-Boas  Ricardo Jorge Pinto Fernandes 《Journal of sports sciences》2019,37(13):1512-1520

We aimed to compare multilayer perceptron (MLP) neural networks, radial basis function neural networks (RBF) and linear models (LM) accuracy to predict the centre of mass (CM) horizontal speed at low-moderate, heavy and severe swimming intensities using physiological and biomechanical dataset. Ten trained male swimmers completed a 7 × 200 m front crawl protocol (0.05 m.s^?1 increments and 30 s intervals) to assess expiratory gases and blood lactate concentrations. Two surface and four underwater cameras recorded independent images subsequently processed focusing a three-dimensional reconstruction of two upper limb cycles at 25 and 175 m laps. Eight physiological and 13 biomechanical variables were inputted to predict CM horizontal speed. MLP, RBF and LM were implemented with the Levenberg-Marquardt algorithm (feed forward with a six-neuron hidden layer), orthogonal least squares algorithm and decomposition of matrices. MLP revealed higher prediction error than LM at low-moderate intensity (2.43 ± 1.44 and 1.67 ± 0.60%), MLP and RBF depicted lower mean absolute percentage errors than LM at heavy intensity (2.45 ± 1.61, 1.82 ± 0.92 and 3.72 ± 1.67%) and RBF neural networks registered lower errors than MLP and LM at severe intensity (2.78 ± 0.96, 3.89 ± 1.78 and 4.47 ± 2.36%). Artificial neural networks are suitable for speed model-fit at heavy and severe swimming intensities when considering physiological and biomechanical background.  相似文献   

Activity-related typologies and longitudinal change in physical activity and sedentary time in children and adolescents: The UP&DOWN Study     

Kate Parker  Anna Timperio  Jo Salmon  Karen Villanueva  Helen Brown  Irene Esteban-Cornejo  Veronica Cabanas-Sánchez  José Castro-Pi?ero  David Sánchez-Oliva  Oscar L. Veiga 《运动与健康科学(英文)》2021,(4):447-453

Background: Children and adolescents can be distinguished by different typologies (clusters) of physical activity and sedentary behavior. How physical activity ...  相似文献   

Arguing in Portugal: A cross-cultural analysis     

Marcin Lewiński  Dale Hample  João Sàágua  Dima Mohammed 《Journal of International and Intercultural Communication》2018,11(3):233-253

We report data on Portuguese understandings of interpersonal arguing, based on a survey conducted in Portugal (N?=?252). Employing concepts and methods developed for studying interpersonal arguing, we report on the levels of argumentativeness, verbal aggressiveness, personalization of conflict, and argument frames. After comparing Portuguese men and women, we compare Portuguese respondents with two groups of US respondents. In contrast to US respondents, Portuguese report to argue more prosocially, cooperatively and civilly, and are more sophisticated in their reflections about arguing. We discuss these results in the context of the Portuguese notion of argumentation (argumentação) and Portuguese culture more broadly.  相似文献   

Current and potential use of fresh frozen cadaver in surgical training and anatomical education     

Yong Keun Song  Dong Hyun Jo 《Anatomical sciences education》2022,15(5):957-969

As surgical procedures continue to be more complex, the need for more effective training in anatomy has increased. The study of anatomy plays a significant role in the understanding of the human body as well as in basic and advanced clinical training. Among the different cadaver models, fresh frozen cadavers (FFCs) are known for their realistic tissue quality. The purpose of this article was to review and summarize the preparation procedures for and reported cases involving FFCs. PubMed, Scopus, Medline, and Web of Science were searched for relevant studies. The preparation procedures were divided into five steps: washing, irrigation, freezing, defrosting, and arterial infusion. Not all steps were reported to be mandatory, but omitting one or more could result in a loss of quality. FFCs were reported to be used for various purposes: undergraduate education, general surgery training, vascular surgery training, minimal access surgery (laparoscopic surgery) training, and microsurgery training. In all categories, expert opinions and statistical analyses indicated successful outcomes. The reasons for high satisfaction with FFCs included realistic texture, capability of reenacting actual operations, and accuracy of anatomical locations. The results also revealed the importance and advantages of the dissection courses in surgical training. Since the direct comparison between cadaver models is insufficient, future studies regarding this topic are deemed necessary. In addition, it would be advantageous to develop methods to improve FFC quality, or ideas to optimize this model for certain purposes.  相似文献