1,025 research outputs found

    An Electromyographic and Video Motion Analysis Study of Elite Sprinters at Varying Speeds and Inclines

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    Every athlete trains with the hopes of being bigger, stronger or faster than the competitor. Athletes are eager to jump on the bandwagon of new training techniques that claim to produce the results the athlete seeks. One such training technique is sprinting on a treadmill at high speeds and inclines. The purpose of this study is to describe muscle activity and joint motion while running on a treadmill at different speeds and inclines. Six males between the ages of 21 and 27 years of age ran at 20 miles per hour and 0% grade and at 13 miles per hour on a 30% grade. Surface electrodes and joint markers were used to analyze electromyographic activity of six muscles and calculate joint angles while running. A descriptive analysis was then performed comparing the two trials. From our results we conclude that the sprinter does adopt different strategies and muscle recruitment patterns to compensate for increases in slope. Examination of range of motion revealed that there was greater overall motion of the hip in the incline trial, motion of the knee was greater during level surface running, while ankle motion remained relatively the same. EMG data showed greater overall activity when sprinting at 13 mph on a 30% incline than when sprinting at 20 mph on a 0% incline

    Thermal-barrier-coated turbine blade study

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    The effects of coating TBC on a CF6-50 stage 2 high-pressure turbine blade were analyzed with respect to changes in the mean bulk temperature, cooling air requirements, and high-cycle fatigue. Localized spallation was found to have a possible deleterious effect on low-cycle fatigue life. New blade design concepts were developed to take optimum advantage of TBCs. Process and material development work and rig evaluations were undertaken which identified the most promising combination as ZrO2 containing 8 w/o Y2O3 applied by air plasma spray onto a Ni22Cr-10Al-1Y bond layer. The bond layer was applied by a low-pressure, high-velocity plasma spray process onto the base alloy. During the initial startup cycles the blades experienced localized leading edge spallation caused by foreign objects

    Everyday Financialization: The Case of UK Households

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    Since the 1970s the UK government has been promoting private asset ownership while decreasing publicly funded welfare programmes. This asset-based welfare approach calls on households to accumulate assets in order to provide financial security during periods of income shortfall. Drawing on a Foucauldian governmentality framework, the dissertation explores how norms of asset ownership are constructed and embedded in households’ discourses and practices. For this purpose, 56 semi-structured interviews with 55 UK households and 60 household members were conducted between 2016 and 2017. The insights gained from the interviews have been supported with an analysis of newspaper articles and put into relation to the wider UK development with the help of household surveys conducted by the government. The findings presented in the thesis reflect empirical, theoretical and methodological contributions. First, looking to debates within the financialization of daily life literature, the empirical findings indicate that households adopt a financialized subject position, albeit differently interpreted than anticipated by the literature. Households accumulate financial and non-financial assets and avoid debt except for asset accumulation purposes. Second, the empirical insights provide the basis for the theoretical contribution. By shedding light on the interplay between asset norms and everyday practices discussions on governmentality and capitalist relations are extended. To be able to save and invest, interviewed households increase work hours, choose a job solely based on income and make sure to work hard while living a nonmaterialistic lifestyle. Through this it is argued here that power relationships incorporated in capital-labour inequalities are strengthened. Third, a methodological contribution is outlined by showing how the employed holistic approach has helped to reveal household financial identities. By providing qualitative empirical insights instead of relying solely on secondary data, it is shown that asset norms are not absorbed in a non-reflected way but are negotiated

    The Machine

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    They stopped in front of one of the many doorways along the dim, narrow corridor. Black letters on frosted glass read..

    Study of improved resins for advanced supersonic technology composites. Part 1: Heteroaromatic polymers containing ether groups. Part 2: Curing chemistry of aromatic polymers and composite studies

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    Fourteen ether-containing, aromatic dianhydrides have been synthesized from N-phenyl-3 or 4-nitrophthalimide and various bisphenols. The process involves nucleophilic displacement of activated nitro groups with bisphenolate ions. Ether-containing dianhydrides were indefinitely stable in the presence of atmospheric moisture. One-step, high temperature solution polymerization of the ether-containing dianhydrides with m-phenylene diamine, 4,4'-oxydianiline and 1, 3-bis(4-aminophenoxy)benzene afforded 42 polyetherimides. The polyetherimides were all soluble in m-cresol except two which were found to be crystalline. The glass transition temperatures of the polyetherimides ranged from 178 to 277 C. Soluble polybenzimidazopyrrolones containing ether groups were also prepared from the same ether-containing dianhydrides and aromatic tetraamines by one-step solution polymerization. Using low molecular weight polyetherimides, various thermoset resin systems were developed and tested as matrices for fiber-reinforced composites. The curing chemistry involving reaction of the phthalonitrile group and the o-diaminophenyl group was found to be generally applicable to crosslinking various aromatic polymers other than polyimides

    Dielectric constants and pair interactions in polar molecules

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    A qualitative description of dielectric processes in Pair interactions of polar molecules is presented, discussing such factors as molecular shape and polarizability. The mathematical treatment of these interactions is given, derived from classical electric field theory and statistical mechanics. The dielectric virial equation and the meaning of the dielectric virial coefficients is discussed. Due to the small magnitude of the coefficients, one must make measurements on the gas of the molar volume to one part in 10 4 and of the dielectric constant to one part in 106 to derive values of the second dielectric virial coefficient to within 10%. A general description of the Burnett and modified Burnett expansion techniques is given, with their application to dielectric measurements. A description of the apparatus which has been assembled is given, including the development of an inexpensive pressure measuring system. The electronic methods used for measuring dielectric constants to one part in 106 to 107 are described, along with those for the pressure measuring system. With humble apologies for being less than perfect, but thankful for being no less than human, I dedicate this to all who have cried upon my shoulders, all whose shoulders I have cried upon, and especially VRVA, BSF, EAM and KAMCW

    Coexpression, copurification, crystallization and preliminary X-ray analysis of a complex of ARL2-GTP and PDE delta

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    The small GTPase ARL2 (from Mus musculus) and an effector protein, the δ subunit of human cGMP phosphodiesterase (hPDE δ), were coexpressed and copurified from Escherichia coli as a stable complex. Coexpression significantly increased the otherwise low yield of PDE δ production in E. coli. The complex, which contains ARL2 in the activated GTP-bound form, was crystallized in two forms. The first belongs to the monoclinic space group P21, with unit-cell parameters a = 48.1, b = 45.7, c = 74.7 Å, β = 94.0° and one complex (39 kDa) in the asymmetric unit. Cryocooled crystals diffract to 2.3 Å using synchrotron radiation. The micro-focused X-­ray beam at beamline ID13 (ESRF) allowed the use of very small crystals, which helped to overcome twinning and enabled the identification of a molecular-replacement solution. The second form recrystallized from the first one after several months. These crystals belong to the orthorhombic space group P212121, with unit-cell parameters a = 44.5, b = 65.4, c = 104.4 Å and one complex in the asymmetric unit. They diffracted to 1.8 Å using synchrotron radiation

    PROPRIEDADES MECÂNICAS DE CHAPAS AGLOMERADAS ESTRUTURAIS FABRICADAS COM MADEIRAS DE PINUS, EUCALIPTO E ACÁCIA-NEGRA

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    Neste trabalho, foram analisadas as propriedades mecânicas de chapas aglomeradas estruturais, fabricadas com madeiras de Pinus elliottii Engelm, Eucalyptus grandis W. Hill ex-Maiden e Acacia mearnsii De Wild. Buscou-se segregar os efeitos da densidade básica da madeira, instalando-se um experimento no delineamento blocos ao acaso em que taxas de compressão de 1,21, 1,32 e 1,43 constituíram os blocos. Quinze tratamentos onde cada espécie participou com 0, 25, 50, 75 ou 100% de proporção em peso seco, foram utilizados para fabricação de chapas aglomeradas estruturais, com partículas de dimensões médias de 90 x 20 x 0,6 mm e coladas com 8% de adesivo à base de tanino-formaldeído. As análises foram realizadas por meio da correlação e ajuste de modelos matemáticos, obtidos por regressão linear simples ou múltipla, entre as variáveis de produção e a proporção de cada espécie na mistura. Os valores obtidos para MOR e MOE ficaram acima dos padrões de qualidade internacionais, no entanto, as chapas apresentaram baixos valores de ligação interna demostrando baixa qualidade de colagem. Como conclusão geral, a mistura de espécies foi mais vantajosa que a utilização de cada espécie individualmente, principalmente em razão da influência das diferentes densidades básicas de cada madeira sobre as propriedades das chapas. A melhor mistura, porém, tem de ser determinada em razão do uso do produto final e da disponibilidade de matéria- -prima

    O impacto da divulgação das demonstrações financeiras no preço das ações

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    Este estudo buscou evidências estatísticas que a divulgação das demonstrações financeiras pelas empresas é capaz de afetar o preço deste ativo no mercado financeiro. Através do estudo de evento e técnicas de apuração e acumulação dos ganhos anormais testou-se a existência de diferença significante nos ganhos anormais durante e fora da janela do evento. Foram testados períodos temporais anteriores e posteriores ao evento, como forma de verificar o vazamento ou atraso na publicidade das demonstrações. Foi verificada também a possível existência de correlação entre as variações ocorridas no preço do ativo e as variações encontradas nos indicadores escolhidos. Estas verificações foram feitas através de regressões lineares simples de cada período temporal com cada indicador. Nenhum dos testes apresentou significância estatística, demonstrando relações muito fracas entre as variações do preço e dos indicadores. A exclusão da hipótese nula não foi possível através do teste escolhido.This study sought statistical evidence that the disclosure of financial statements by companies is capable of affecting the price of this asset in the financial market. Through the study of the event and techniques of calculation and accumulation of the abnormal gains, it was tested the existence of a significant difference in the abnormal gains during and outside the window of the event. Time periods prior to and after the event were tested as a means of verifying the leak or delay in advertising the statements. It was also verified the possible existence of correlation between the variations occurred in the price of the asset and the variations found in the chosen indicators. These checks were made through simple linear regressions of each time period with each indicator. None of the tests presented statistical significance, showing very weak relationships between price and indicator variations. The exclusion of the null hypothesis was not possible through the chosen test
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