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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Effect of sodium bicarbonate and glycogen depletion on 1500M time trials

Behr, Laura. January 2002 (has links)
Thesis (M.S.)--University of Wisconsin--La Crosse, 2002. / Includes bibliographical references.
312

The effect of an anterior cruciate ligament deficiency on steady-rate cycling biomechanics

Hunt, Michael Anthony. January 2002 (has links)
Thesis (M.S.)--University of British Columbia, 2002. / Includes bibliographical references (leaves 34-37).
313

The effect of intermittent simulated altitude exposure via re-breathing on cycling performance

Babcock, Carmen J. January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 113-118).
314

Marine nitrogen fixation : Cyanobacterial nitrogen fixation and the fate of new nitrogen in the Baltic Sea

Klawonn, Isabell January 2015 (has links)
Biogeochemical processes in the marine biosphere are important in global element cycling and greatly influence the gas composition of the Earth’s atmosphere. The nitrogen cycle is a key component of marine biogeochemical cycles. Nitrogen is an essential constituent of living organisms, but bioavailable nitrogen is often short in supply thus limiting primary production. The largest input of nitrogen to the marine environment is by N2-fixation, the transformation of inert N2 gas into bioavailable ammonium by a distinct group of microbes. Hence, N2-fixation bypasses nitrogen limitation and stimulates productivity in oligotrophic regions of the marine biosphere. Extensive blooms of N2-fixing cyanobacteria occur regularly during summer in the Baltic Sea. N2-fixation during these blooms adds several hundred kilotons of new nitrogen into the Baltic Proper, which is similar in magnitude to the annual nitrogen load by riverine discharge and more than twice the atmospheric nitrogen deposition in this area. N2-fixing cyanobacteria are therefore a critical constituent of nitrogen cycling in the Baltic Sea. In this thesis N2 fixation of common cyanobacteria in the Baltic Sea and the direct fate of newly fixed nitrogen in otherwise nitrogen-impoverished waters were investigated. Initially, the commonly used 15N-stable isotope assay for N2-fixation measurements was evaluated and optimized in terms of reliability and practicality (Paper I), and later applied for N2-fixation assessments (Paper II–IV). N2 fixation in surface waters of the Baltic Sea was restricted to large filamentous heterocystous cyanobacteria (Aphanizomenon sp., Nodularia spumigena, Dolichospermum spp.) and absent in smaller filamentous cyanobacteria such as Pseudanabaena sp., and unicellular and colonial picocyanobacteria (Paper II-III). Most of the N2-fixation in the Northern Baltic Proper was contributed by Aphanizomenon sp. due to its high abundance throughout the summer and similar rates of specific N2-fixation as Dolichospermum spp. and N. spumigena. Specific N2 fixation was substantially higher near the coast than in an offshore region (Paper II). Half of the fixed nitrogen was released as ammonium at the site near the coast and taken up by non-N2-fixing organisms including phototrophic and heterotrophic, prokaryotic and eukaryotic planktonic organisms. Newly fixed nitrogen was thereby rapidly turned-over in the nitrogen-depleted waters (Paper III). In colonies of N. spumigena even the potential for a complete nitrogen cycle condensed to a microcosm of a few millimeters could be demonstrated (Paper IV). Cyanobacterial colonies can therefore be hot-spots of nitrogen transformation processes potentially including nitrogen gain, recycling and loss processes. In conclusion, blooms of cyanobacteria are instrumental for productivity and CO2 sequestration in the Baltic Sea. These findings advance our understanding of biogeochemical cycles and ecosystem functioning in relation to cyanobacterial blooms in the Baltic Sea with relevance for both ecosystem-based management in the Baltic Sea, and N2-fixation and nitrogen cycling in the global ocean. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.</p>
315

Ciclismo urbano : a perspectiva de cicloativistas da cidade de São Paulo /

Troncoso, Leandro Dri Manfiolete. January 2017 (has links)
Orientador: Rodolfo Franco Puttini / Banca: Luiz Gonçalves Junior / Banca: Giuliano Gomes Assis Pimentel / Resumo: O objetivo desta pesquisa foi compreender a prática social do ciclismo na perspectiva de cicloativistas da cidade de São Paulo. O ato de pedalar bicicleta é uma forma de mobilidade ativa pelas pessoas, porém, entendendo "ciclismo urbano" diferente de "ciclismo desportivo", a bicicleta não tem sido estimada como bem simbólico pela sociedade. O principal argumento está dado na valorização excessiva do transporte motorizado individual. No contexto da pesquisa qualitativa em Motricidade Humana importa incluir a minha experiência como pesquisador e de quatro ciclistas que defendem a causa cicloativista. A técnica de análise do fenômeno situado consiste em três momentos: 1) análise ideográfica dos discursos para identificação das unidades de significado; 2) formação da matriz nomotética pelas convergências discursivas e 3) síntese dos resultados. A discussão sobre o fenômeno contextualizado do ciclismo perpassa por duas categorias temáticas: A) "A experiência transformativa do ser que pedala" e B) "O direito de pedalar na cidade". Destaca-se a ideia "Pedalar por Cidadania" como elemento do campo simbólico da saúde / Abstract: The aim of this research was to understand the social practice of bicycling in the perspective of cyclists in the city of São Paulo. The act of bicycling is a form of active mobility by people. However, understanding "urban cycling" other than "sporting cycling", the bicycle has not been considered as a symbolic good by society. The main argument given in the excessive valuation of individual motorized transport. In the context of the qualitative research in Human Motricity is important to include my experience as a researcher and of four cyclists who defend the cycloativist cause. The technique of analysis of the situated phenomenon consists of three moments: 1) ideographic analysis of discourses to identify the units of meaning, 2) formation of the nomothetic matrix by the discursive and 3) synthesis of the results. The discussion about the contextualized phenomenon of cycling runs through two thematic categories: A) "The transformative experience of the pedaling being" and B) "The right to pedal in the city". It stands out the idea "Pedaling for Cityzenship" as an element of the symbolic field of health / Mestre
316

Desenvolvimento de um protótipo de sistema inteligente para análise da técnica de pedalada apresentada por ciclistas

Pigatto, André Vieira January 2018 (has links)
Este trabalho apresenta o desenvolvimento de um sistema inteligente para análise da técnica de pedalada aplicada por ciclistas. Para isso, desenvolveu-se um par de pedais de encaixe instrumentados, a partir dos quais é possível medir a componente de força normal aplicada nas partes frontal e posterior dos pedais. O modelo virtual da célula de carga experimental foi desenvolvido através da digitalização dos pedais de encaixe comerciais, utilizando-se um sistema comercial de escaneamento 3D com precisão declarada de 0,1mm. Cada pedal foi instrumentado com oito extensômetros de resistência elétrica (HBM 1-LY-13-1.5/350). Posteriormente os carregamentos máximos em cada eixo de medida de força foram estabelecidos utilizando-se uma plataforma de aquisição comercial específica para medida de deformação mecânica. Considerando-se os valores determinados, desenvolveu-se o circuito de condicionamento e realizaram-se os ensaios de deformação estática, obtendo-se as funções de transferência de saída de tensão elétrica em função do carregamento mecânico. O erro de linearidade máximo, considerando todos os canais, ficou abaixo de 0,75% e a máxima incerteza expandida (k=2) por canal, obtida através da aplicação do método clássico, foi de 1,55%. Em sequência, integrouse o sistema de pedais desenvolvido a dois outros sistemas, são eles: um par pedivelas experimentais instrumentados, capazes de medir as três componentes da força aplicada aos pedais e transmitidas aos pedivelas com um erro de linearidade abaixo de 0,6% e uma incerteza combinada inferior a 3,22%, e um sistema de cinemetria comercial, cuja precisão declarada pelo fabricante é de 1mm. Para possibilitar uma comparação quantitativa entre treinos ou ciclistas, implementou-se um sistema inteligente, baseado em redes Neuro-Fuzzy (ANFIS). A partir dos valores da potência média, do desvio padrão da potência e da assimetria bilateral média, obtidos ao longo de ensaios realizados sob protocolo desenvolvido especificamente para este trabalho, um score que representa o nível da técnica de pedalada apresentado pelo ciclista é determinado. Com intuito de testar o sistema, desenvolveu-se um projeto de experimentos com 2 fatores controláveis (sujeito e nível de frenagem de um rolo de treinamento), e realizou-se ensaios com oito ciclistas de características fisiológicas e níveis de preparos distintos. Através da análise estatística, constatou-se que das 23 variáveis de resposta consideradas ao longo do experimento, 23 são influenciadas significativamente pelo fator controlado sujeito e oito são influenciadas significativamente pelo fator controlado nível de frenagem magnética. / This report describes the development of an intelligent pedaling technique analysis system. To accomplish that, a pair of road bicycle pedals (SHIMANO R540) were instrumented to measure the forces that are applied to the front and back regions of the pedals. The virtual models of the pedals were developed based on a 3D scanned mesh developed with aid of a commercial 3D scanning system with a precision of 0.1mm. Each pedal was instrumented with eight electrical resistance strain-gages (HBM 1-LY-13-1.5/350). After that, the range of the mechanical deformation of each measurement channel was determined with aid of an industrial deformation acquisition system. The conditioning circuit was developed based on the mechanical deformation ranges previously determined and the static calibration experiment was performed to determine the voltage output transfer functions. The maximum linearity error determined per channel was 0,75% and the maximum expanded uncertainty (k=2), determined applying the classical methodology, was 1,55%. After that, the instrumented pedals developed were integrated with two complementary systems, which are: a pair of instrumented crank arm load cells which measure the components of the force applied to the bicycle pedal with a linearity error under 0.6% and an uncertainty of 3,22% and an Optitrack motion track system with a declared accuracy of 1mm. An intelligent pedaling technique analysis system was implemented through an Adaptive Neuro Fuzzy Inference System (ANFIS) to determine the cyclist pedaling technique score based on three inputs: the average power applied to bicycle pedal, the average power standard deviation and the bilateral asymmetry index, all of them collected under an experimental protocol specifically designed for this application. To evaluate the behavior of the system developed a randomized block experiment design with two controlled factors was performed indoor with aid of an ergometer roll; 160 sprints were conducted with eight subjects of different training levels. From the data collected an ANOVA test was performed, which confirmed that all the 23 response variables vary significantly in function of the subject’s controlled factor and eight of them vary significantly in function of the magnetic braking level.
317

Constraining the carbon budgets of croplands with Earth observation data

Revill, Andrew January 2016 (has links)
Cropland management practices have traditionally focused on maximising the production of food, feed and fibre. However, croplands also provide valuable regulating ecosystem services, including carbon (C) storage in soil and biomass. Consequently, management impacts the extents to which croplands act as sources or sinks of atmospheric carbon dioxide (CO2). And so, reliable information on cropland ecosystem C fluxes and yields are essential for policy-makers concerned with climate change mitigation and food security. Eddy-covariance (EC) flux towers can provide observations of net ecosystem exchanges (NEE) of CO2 within croplands, however the tower sites are temporally and spatially sparse. Process-based crop models simulate the key biophysical mechanisms within cropland ecosystems, including the management impacts, crop cultivar, soil and climate on crop C dynamics. The models are therefore a powerful tool for diagnosing and forecasting C fluxes and yield. However, crop model spatial upscaling is often limited by input data (including meteorological drivers and management), parameter uncertainty and model complexity. Earth observation (EO) sensors can provide regular estimates of crop condition over large extents. Therefore, EO data can be used within data assimilation (DA) schemes to parameterise and constrain models. Research presented in this thesis explores the key challenges associated with crop model upscaling. First, fine-scale (20-50 m) EO-derived data, from optical and radar sensors, is assimilated into the Soil-Plant-Atmosphere crop (SPAc) model. Assimilating all EO data enhanced the simulation of daily C exchanges at multiple European crop sites. However, the individually assimilation of radar EO data (as opposed to combined with optical data) resulted in larger improvements in the C fluxes simulation. Second, the impacts of reduced model complexity and driver resolution on crop photosynthesis estimates are investigated. The simplified Aggregated Canopy Model (ACM) – estimating daily photosynthesis using coarse-scale (daily) drivers – was calibrated using the detailed SPAc model, which simulates leaf to canopy processes at half-hourly time-steps. The calibrated ACM photosynthesis had a high agreement with SPAc and local EC estimates. Third, a model-data fusion framework was evaluated for multi-annual and regional-scale estimation of UK wheat yields. Aggregated model yield estimates were negatively biased when compared to official statistics. Coarse-scale (1 km) EO data was also used to constrain the model simulation of canopy development, which was successful in reducing the biases in the yield estimates. And fourth, EO spatial and temporal resolution requirements for crop growth monitoring at UK field-scales was investigated. Errors due to spatial resolution are quantified by sampling aggregated fine scale EO data on a per-field basis; whereas temporal resolution error analysis involved re-sampling model estimates to mimic the observational frequencies of current EO sensors and likely cloud cover. A minimum EO spatial resolution of around 165 m is required to resolve the field-scale detail. Monitoring crop growth using EO sensors with a 26-day temporal resolution results in a mean error of 5%; however, accounting for likely cloud cover increases this error to 63%.
318

O ciclismo nos clubes de Porto Alegre/RS : entre o passado e o presente

Moraes, Ronaldo Dreissig de January 2014 (has links)
O ciclismo é uma das práticas esportivas que foi organizada em associações em Porto Alegre na segunda metade do século XIX. O presente estudo tem como objetivo reconstruir as memórias da prática do ciclismo em clubes da cidade de Porto Alegre, desde a segunda metade do século XIX até meados da década de 1940. Para a construção dessa pesquisa, as fontes documentais consultadas foram os jornais “A Federação” e o “Correio do Povo”. As fontes revelaram que a prática do ciclismo em clubes na cidade de Porto Alegre, iniciou em 1895, com a fundação da União Velocipédica de Amadores, primeira associação destinada ao desenvolvimento dessa prática esportiva. No ano seguinte, em 1896, foi fundada a Radfahrer Verein Blitz. Essas duas associações rivalizaram nas competições de ciclismo nas pistas, mas também fora delas. No princípio do século XX, com a organização dos primeiros clubes de futebol em Porto Alegre, a prática do ciclismo sofreu um abalo, também em razão da migração de dirigentes esportivos para os clubes de futebol. Após um período de enfraquecimento do ciclismo nos clubes, nos anos de 1930, a prática foi retomada com certo destaque nos jornais. Um acontecimento marcante no período foi a organização da Federação Gaúcha de Ciclismo, em 1935. A década de 1940 mostra um novo período de declínio para o ciclismo, onde a divulgação dessa prática esportiva se torna escassa nas fontes consultadas. Atualmente, o ciclismo está retornando ao cotidiano da cidade de Porto Alegre, não como uma prática esportiva competitiva, mas como uma atividade de lazer ou como meio de transporte. / Cycling is a pratices sports that was organized in associations in Porto Alegre in the second half of the 19th century. The present study aims to reconstruct the memories of the practice of cycling in clubs in the city of Porto Alegre, since the second half of the 19th century until the mid-1940. For the construction of this research, the documentary sources consulted were the newspapers "A Federação" and "Correio do Povo". The sources revealed that the practice of cycling in clubs in the city of Porto Alegre, began in 1895, with the Foundation of União Velocipédica de Amadores, first Association for the development of sports. The following year, in 1896, was founded the Radfahrer Verein Blitz. These two associations feuded in cycling on the slopes, but also outside them. At the beginning of the 20th century, with the organization of the first football clubs in Porto Alegre, the practice of cycling suffered a concussion, also due to the migration of sports leaders for football clubs. After a period of weakening of cycling in clubs, in the years of 1930, the practice was resumed with a certain emphasis in the papers. A landmark event in the period was the organization of Federação Gaúcha de Ciclismo, in 1935. The Decade of 1940 shows a new period of decline for cycling, where disclosure of sports becomes scarce in the sources consulted. Currently, cycling is returning to everyday life in the city of Porto Alegre, not as a competitive sport, but as a leisure activity or as a means of transportation.
319

Desenvolvimento de um protótipo de sistema inteligente para análise da técnica de pedalada apresentada por ciclistas

Pigatto, André Vieira January 2018 (has links)
Este trabalho apresenta o desenvolvimento de um sistema inteligente para análise da técnica de pedalada aplicada por ciclistas. Para isso, desenvolveu-se um par de pedais de encaixe instrumentados, a partir dos quais é possível medir a componente de força normal aplicada nas partes frontal e posterior dos pedais. O modelo virtual da célula de carga experimental foi desenvolvido através da digitalização dos pedais de encaixe comerciais, utilizando-se um sistema comercial de escaneamento 3D com precisão declarada de 0,1mm. Cada pedal foi instrumentado com oito extensômetros de resistência elétrica (HBM 1-LY-13-1.5/350). Posteriormente os carregamentos máximos em cada eixo de medida de força foram estabelecidos utilizando-se uma plataforma de aquisição comercial específica para medida de deformação mecânica. Considerando-se os valores determinados, desenvolveu-se o circuito de condicionamento e realizaram-se os ensaios de deformação estática, obtendo-se as funções de transferência de saída de tensão elétrica em função do carregamento mecânico. O erro de linearidade máximo, considerando todos os canais, ficou abaixo de 0,75% e a máxima incerteza expandida (k=2) por canal, obtida através da aplicação do método clássico, foi de 1,55%. Em sequência, integrouse o sistema de pedais desenvolvido a dois outros sistemas, são eles: um par pedivelas experimentais instrumentados, capazes de medir as três componentes da força aplicada aos pedais e transmitidas aos pedivelas com um erro de linearidade abaixo de 0,6% e uma incerteza combinada inferior a 3,22%, e um sistema de cinemetria comercial, cuja precisão declarada pelo fabricante é de 1mm. Para possibilitar uma comparação quantitativa entre treinos ou ciclistas, implementou-se um sistema inteligente, baseado em redes Neuro-Fuzzy (ANFIS). A partir dos valores da potência média, do desvio padrão da potência e da assimetria bilateral média, obtidos ao longo de ensaios realizados sob protocolo desenvolvido especificamente para este trabalho, um score que representa o nível da técnica de pedalada apresentado pelo ciclista é determinado. Com intuito de testar o sistema, desenvolveu-se um projeto de experimentos com 2 fatores controláveis (sujeito e nível de frenagem de um rolo de treinamento), e realizou-se ensaios com oito ciclistas de características fisiológicas e níveis de preparos distintos. Através da análise estatística, constatou-se que das 23 variáveis de resposta consideradas ao longo do experimento, 23 são influenciadas significativamente pelo fator controlado sujeito e oito são influenciadas significativamente pelo fator controlado nível de frenagem magnética. / This report describes the development of an intelligent pedaling technique analysis system. To accomplish that, a pair of road bicycle pedals (SHIMANO R540) were instrumented to measure the forces that are applied to the front and back regions of the pedals. The virtual models of the pedals were developed based on a 3D scanned mesh developed with aid of a commercial 3D scanning system with a precision of 0.1mm. Each pedal was instrumented with eight electrical resistance strain-gages (HBM 1-LY-13-1.5/350). After that, the range of the mechanical deformation of each measurement channel was determined with aid of an industrial deformation acquisition system. The conditioning circuit was developed based on the mechanical deformation ranges previously determined and the static calibration experiment was performed to determine the voltage output transfer functions. The maximum linearity error determined per channel was 0,75% and the maximum expanded uncertainty (k=2), determined applying the classical methodology, was 1,55%. After that, the instrumented pedals developed were integrated with two complementary systems, which are: a pair of instrumented crank arm load cells which measure the components of the force applied to the bicycle pedal with a linearity error under 0.6% and an uncertainty of 3,22% and an Optitrack motion track system with a declared accuracy of 1mm. An intelligent pedaling technique analysis system was implemented through an Adaptive Neuro Fuzzy Inference System (ANFIS) to determine the cyclist pedaling technique score based on three inputs: the average power applied to bicycle pedal, the average power standard deviation and the bilateral asymmetry index, all of them collected under an experimental protocol specifically designed for this application. To evaluate the behavior of the system developed a randomized block experiment design with two controlled factors was performed indoor with aid of an ergometer roll; 160 sprints were conducted with eight subjects of different training levels. From the data collected an ANOVA test was performed, which confirmed that all the 23 response variables vary significantly in function of the subject’s controlled factor and eight of them vary significantly in function of the magnetic braking level.
320

Rhythmic arm cycling training improves walking and interlimb integrity in chronic stroke

Kaupp, Chelsea 24 December 2018 (has links)
Training locomotor pattern generating networks (CPGs) with body weight supported treadmill training or through arm and leg cycling improves walking in chronic stroke. These outcomes are presumed to result from enhanced interlimb connectivity and CPG function. The extent to which rhythmic arm training activates interlimb CPG networks for locomotion remains unclear and was assessed by studying chronic stroke participants before and after 5-weeks of arm cycling training. Strength was assessed bilaterally via maximal voluntary isometric contractions in the legs and hands. Muscle activation during arm cycling and transfer to treadmill walking were assessed in the more affected (MA) and less affected (LA) sides via surface electromyography. Changes to interlimb coupling during rhythmic movement were evaluated using modulation of cutaneous reflexes elicited by electrical stimulation of the superficial radial nerve at the wrist. Bilateral soleus stretch reflexes were elicited at rest and during 1Hz arm cycling. Clinical function tests assessed walking, balance and motor function. Results show significant changes in function and neurophysiological integrity. Training increased bilateral grip strength, force during MA plantarflexion and muscle activation. ‘Normalization’ of cutaneous reflex modulation was found during arm cycling. There was enhanced activity in the dorsiflexor muscles on the MA side during swing phase of walking. Enhanced interlimb coupling was shown by increased modulation of MA soleus stretch reflexes amplitudes during arm cycling after training. Clinical evaluations showed enhanced walking ability and balance. These results are consistent with training-induced changes in CPG function and interlimb connectivity and underscore the need for arm training in the functional rehabilitation of walking after neurotrauma. / Graduate

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