Thesis--Catholic University of America. / Bibliography: p. 266-277.

Texte remanié de: Thesis Ph. D.--Berlin--Free university, 2006. Titre de soutenance : Protest, opportunities, and mechanisms : a theory of social movements and political change. / Bibliogr. p. 295-329.

La mise en échec corporelle (MÉC) dans le hockey mineur est considérée comme l’un des grands débats dans le monde du sport. Plusieurs études ont démontré que le risque de blessure est plus élevé dans des ligues évoluant avec la MÉC contrairement à celles évoluant sans la MÉC. L’objectif de cette étude est de comparer l’incidence des contacts physiques associés à la MÉC chez des joueurs de hockey sur glace de catégorie bantam, selon leur expérience de la MÉC dans la catégorie peewee. Au moment de cette étude, les règlements à l’égard de l’utilisation de la MÉC étaient différents pour la région de Québec (MÉC interdite pour la catégorie peewee) et la région de Calgary (MÉC permise pour la catégorie peewee). Au total, 9 039 contacts physiques (CP) ont été observés en 31 parties (Calgary, n=16; Québec, n=15). Les résultats démontrent que peu de différences significatives ont été observées. / To determine whether the incidence and types of body contact differ for Bantam players (aged 13–14 years) who were exposed to body checking (BC) at Peewee level (aged 11–12 years) in Calgary, Alberta versus Bantam players who were not exposed to BC at Pee Wee level in Québec City, Québec. A cohort study was conducted during the 2008–2009 ice hockey season. Sixteen games for Calgary and 15 for Québec City were randomly selected and analyzed with a validated observation system. A total of 5,610 incidences of body contact with the trunk and 3,429 other types of body contact were observed. Level 1 contact was more frequent in Québec City ([ARR]: 1.71; 95% CI: 1.28–2.29). Hooking (ARR: 2.18; 95% CI: 1.42–3.32) and slashing (ARR: 3.35; 95% CI: 1.31–8.58) were more frequent in Calgary. Results suggest that players’ behaviors can differ, but not significantly.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-06T20:54:52Z No. of bitstreams: 1 GEORGE CARLOS DOS SANTOS ANSELMO - TESE PPG-CEMat 2014..pdf: 19735821 bytes, checksum: c92e61b342c27548f43bd01d30640a96 (MD5) / Made available in DSpace on 2018-04-06T20:54:52Z (GMT). No. of bitstreams: 1 GEORGE CARLOS DOS SANTOS ANSELMO - TESE PPG-CEMat 2014..pdf: 19735821 bytes, checksum: c92e61b342c27548f43bd01d30640a96 (MD5) Previous issue date: 2014-08-29 / Ligas com efeito de memória de forma possuem grande potencial para aplicações nos setores da robótica, automotivo, aeronáutico, medicina e na produção de atuadores miniaturizados. O objetivo desse trabalho foi investigar e desenvolver materiais com efeito de memória de forma (Shape Memory Effect - SME) das ligas Ti-Ni-Cu na forma de fitas micrométricas produzidos por meio de Melt Spinning. A metodologia utilizada para produção das ligas Ti-Ni-Cu foi via fusão a plasma (Plasma Skull Push-Pull), e para fabricação de fitas utilizou-se a técnica de solidificação rápida por injeção de metal líquido em volante de cobre nas velocidades de 38 e 50 m/s, logos após as ligas e fitas Ti-Ni-Cu foram caracterizadas por: DSC, SMRT, DRX, MEV. Inicialmente barras prismáticas da liga Ti-Ni50-x-Cux (x=3,4,5,6,7%at.Cu) foram produzidas via fusão a plasma. Por meio solidificação rápida obteve-se fitas com espessuras de 30 a 45 µm com a variação da velocidade do volante de cobre de 38 e 50 m/s no Melt Spinning. Ensaios de DRX revelam à presença da fase B19’ nas ligas brutas de fusão a temperatura ambiente. As ligas apresentaram transformações de fase em único estágio B2↔B19`. As temperaturas de transformação As das ligas Ti-Ni-Cu decrescem com o incremento de Cu. Concluise que as temperaturas de transformação martensíticas (Ms) de fitas Ti-Ni-Cu decrescem com a diminuição do tamanho de grão, e os valores de histerese e entalpia decrescem quando altas taxas de super-resfriamento são alcançadas no Melt Spinnig. / Alloys with shape memory effect have immense potential for applications in robotics, automotive and aeronautics industry, medicine and in the production of miniaturized actuators. The aim of this study was to investigate, develop and manufacture materials with shape memory effect of Ti-Cu-Ni alloys in the form of micrometer tapes produced by Melt Spinning. The methodology used for the production of Ti-Cu-Ni alloys by fusion plasma (Plasma Skull Push-Pull), and manufacturing tapes used the technique of rapid solidification injection of liquid metal into the copper wheel speeds 38 and 50 m/s. alloy and Ti-Ni-Cu ribbons were characterization by: DSC, SMRT, XRD, SEM. Initially prismatic bars of Ti-Ni50-x-Cux (x = 3,4,5,6,7 at.Cu%) had been produced by plasma fusion. With the rapid solidification is obtained tapes with thicknesses between 30 to 45 µm with the variation of the speed of the wheel covers 38 and 50 m / s the melt spinning. XRD tests reveal the presence of the B19' in gross phase alloy melting temperature. The alloys showed phase transformations in single stage B2↔B19`. The transformation temperatures of the alloy Ti-Cu-Ni decrease with the increase of Cu. We conclude that the temperatures of martensitic transformation (Ms) of Ti-Ni-Cu ribbons decreases with decreasing grain size, and hysteresis values and enthalpy decreases when high rates of super-cooling are achieved in Melt Spinnig.

Depuis de nombreuses années, l’introduction de la mise en échec corporelle (MÉC) dans le hockey mineur anime plusieurs discussions au sein de la population canadienne. Plusieurs études ont démontré que le risque de blessures est plus élevé dans des ligues de catégorie peewee évoluant avec la MÉC contrairement à celles évoluant sans la MÉC. En revanche, rares sont les études qui ont mis au centre de leur réflexion son impact sur le développement global des joueurs. L’objectif de cette étude est de comparer, grâce au Team Sport Assessment Procedure adapté au hockey sur glace, la performance offensive des joueurs peewee évoluant avec la MÉC (Calgary) et sans la MÉC (Québec). Les actions réalisées en possession de la rondelle ont été comptabilisées pour 280 joueurs de Québec et 272 joueurs de Calgary. Les résultats des régressions de Poisson démontrent que peu de différences significatives ont été obtenues entre la performance des joueurs de ces deux cohortes pour les variables étudiées. / The practice of body-checking (BC) in minor hockey has sparked a lengthy series of debates among Canadians. Recent studies have shown that players are at much greater risk for injury in leagues that allow BC compared to those that do not. However, few studies have examined the impact of BC on the offensive development of peewee players (aged 11–12 years). The purpose of this study was to compare the offensive performance of peewee players that practice BC (Calgary) or not (Quebec City) using the Team Sport Assessment Procedure adapted for hockey. A total of 280 players in Quebec City and 272 equivalent-level players in Calgary were videotaped handling the puck in competitive play during the 2007–2008 season. Poisson regression results for the variables and performance indexes indicate no significant differences in offensive performance between players who used BC or not. Expert opinions that introducing BC at a young age can improve overall development of hockey skills are therefore not supported.