The force-time profile of elite front crawl swimmers     

Formosa DP  Mason B  Burkett B 《Journal of sports sciences》2011,29(8):811-819

In this study, we used recently developed technology to determine the force-time profile of elite swimmers, which enabled coaches to make informed decisions on technique modifications. Eight elite male swimmers with a FINA (Federation Internationale de Natation) rank of 900+ completed five passive (streamline tow) and five net force (arms and leg swimming) trials. Three 50-Hz cameras were used to video each trial and were synchronized to the kinetic data output from a force-platform, upon which a motorized towing device was mounted. Passive and net force trials were completed at the participant's maximal front crawl swimming velocity. For the constant tow velocity, the net force profile was presented as a force-time graph, and the limitation of a constant velocity assumption was acknowledged. This allowed minimum and maximum net forces and arm symmetry to be identified. At a mean velocity of 1.92+0.06 m s?1, the mean passive drag for the swimmers was 80.3+4.0 N, and the mean net force was 262.4+33.4 N. The mean location in the stroke cycle for minimum and maximum net force production was at 45% (insweep phase) and 75% (upsweep phase) of the stroke, respectively. This force-time profile also identified any stroke asymmetry.  相似文献   

The possibility of deliberate norm-adherence in AI     

Swanepoel  Danielle 《Ethics and Information Technology》2021,23(2):157-163

Ethics and Information Technology - Moral agency status is often given to those individuals or entities which act intentionally within a society or environment. In the past, moral agency has...  相似文献   

Tweet Up? Examining Twitter's Impact on Social Capital and Digital Citizenship in Higher Education          下载免费PDF全文

Danielle Morgan Acosta 《About Campus》2014,18(6):10-17

Twitter is a highly accessible communication venue that is embraced by great numbers of traditionally aged and ethnically diverse college students. Danielle Morgan Acosta challenges us to turn our research and teaching attention to the potential of Twitter to support student learning.  相似文献   

An Investigation of How a Physics Professional Development Course Influenced the Teaching Practices of Five Elementary School Teachers     

Danielle B. Harlow 《Journal of Science Teacher Education》2014,25(1):119-139

This paper reports the results of an investigation of how a professional development content course based on the Physics and Everyday Thinking (PET) curriculum affected the teaching practices of five case study elementary school teachers. The findings of this study highlight different ways that teachers use what they learn in content courses to teach science to elementary children. While some teachers transferred pedagogical practices along with the content, others transformed the content to be useful in already existing pedagogical frameworks, and still others show little or no evidence of transfer. The range of transfer is explained by considering how each teacher interacted with the learning context (the PET curriculum) and their initial ideas about teaching science.  相似文献   

In vitro antioxidant activity and potential inhibitory action against α-glucosidase of polysaccharides from fruit peel oftea (Camellia sinensis L.)简   总被引：1，自引：0，他引：1  

Yue-fei Wang  Jie Wang  Jing Wu  Ping Xu  Yi-qi Wang  Jun-jie Gao  Danielle Hochstetter 《Journal of Zhejiang University. Science. B》2014,15(2):173-180

The conditions for extracting polysaccharides from tea (Camellia sinensis L.) fruit peel (TFPPs) were studied. Three parameters (temperature, time, and liquid/solid ratio) affecting the extraction of TFPP were optimized using response surface methodology (RSM). Under the optimized conditions, the yield of TFPP was predicted to be 4.98%. The physicochemical properties, in vitro antioxidant activities, and inhibitory effects on α-glucosidase of fractionated TFPPs (TFPP-0, TFPP-20, TFPP-40, and TFPP-60) were investigated. We found that the TFPPs were all acid protein-bound heteropolysaccharides, although with different chemical compositions. They had not only remarkable scavenging activity on 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and reducing activity, but also excellent inhibitory potential against α-glucosidase in vitro. Our results suggest that tea fruit peel could be treated as a potential bioresource for the development of polysaccharide antioxidants.  相似文献   

Statement of Editorial Policy     

Willis F. Overton  & Danielle L. Horvath 《Monographs of the Society for Research in Child Development》2000,65(2):107-108

  相似文献   

Anthropometric profiles of elite older triathletes in the Ironman Brazil compared with those of young Portuguese triathletes and older Brazilians     

Silva DA  Benedetti TR  Ferrari EP  Meurer ST  Antes DL  Silva AM  Santos DA  Matias CN  Sardinha LB  Vieira F  Petroski EL 《Journal of sports sciences》2012,30(5):479-484

The objective of this study was to describe the anthropometric profiles of elite older triathletes participating in the 2009 Ironman Brazil and to compare their somatotype, anthropometric and body composition characteristics with those of elite young triathletes and older non-athletes. The sample consisted of 64 males, divided into three groups: (1) older triathletes (n = 17), (2) young triathletes (n = 24), and (3) older non-athletes (n = 23). Somatotype was analysed according to the Carter and Heath ( 1990 ) method. Body mass index, sum of four skinfolds, percentage body fat, body fat mass, and fat-free mass were also estimated. Older non-athletes had higher endomorphy, sum of four skinfolds, fat percentage, and body fat mass than the athletes. Older athletes who participated in the Ironman and elite young triathletes had higher fat-free mass than older non-athletes. Older triathletes and older non-athletes were considered mainly endomorphic mesomorphs and young triathletes mainly ectomorphic mesomorphs. The findings that characterize the anthropometric profile of athletes in this sports modality could be used as a reference.  相似文献   

Lombroso's Legacy: The Miseducation of Criminologists     

John P. Wright  Kevin M. Beaver  Matt DeLisi  Michael G. Vaughn  Danielle Boisvert  Jamie Vaske 《Journal of Criminal Justice Education》2013,24(3):325-338

This study examines the extent to which criminal justice and criminology Ph.D. students are exposed to contemporary biological and genetic findings associated with aggression and violence. Drawing on multiple sources of information, we find little evidence showing that Ph.D. students are exposed to any biological research on crime and offending. We examine the consequences for this “trained incompetence” and offer suggestions for remedying this deficiency.

If all mankind minus one were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind. (John Stuart Mill)  相似文献   

Martin to Brown     

Danielle K. Kilgo  Rachel R. Mourao  George Sylvie 《Journalism Practice》2019,13(4):413-430

The rise of the modern Black Lives Matter movement can be traced back to two key events, the 2012 death of Trayvon Martin and the 2014 death of Michael Brown. Research routinely showed that mainstream media’s narrative choices marginalize and delegitimize protesters and their causes, a pattern known as the protest paradigm. This study provides a longitudinal examination of how the same mainstream media system varied in their coverage of similar events and the degree to which journalists challenged the predicted paradigms conceptualized in other academic work. A content analysis of national newspaper coverage revealed that news before the judicial rulings focused on protesters’ tactics (violence versus peaceful) and changed to the realm of ideas (grievances and demands) after the assailants were considered not guilty of wrongdoing. No progression was found in legitimizing coverage of protests between the two cases.  相似文献   

Cheating Behaviors among Undergraduate College Students: Results from a Factorial Survey     

Tina L. Freiburger  Danielle M. Romain  Blake M. Randol  Catherine D. Marcum 《Journal of Criminal Justice Education》2017,28(2):222-247

Using a factorial survey administered to college students at two Universities, this study examines students’ tendencies to engage in academic misconduct. The relation of strain, self-control, and deterrence theories to likelihood of cheating are further explored. The results suggest that increasing the severity of the punishment for cheating does not deter academic misconduct; however, several variables indicating an increased certainty of being caught did decrease the likelihood of cheating behaviors. Only the strain variables that indicated a student had an ill family member or that the student found the course difficult significantly increased academic misconduct. Although self-control did not have a direct effect on cheating it indirectly affected cheating behaviors through students’ perceptions of getting caught and their perception of wrongfulness of the cheating behavior. Policy and future research implications of the findings are further discussed.  相似文献