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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.
41

Postural changes in circulation and respiration in relation to activity of the antigravity muscles

Brogdon, Ruth Elizabeth, January 1940 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [27]-[28]).
42

Effects of emphysema and chronic hypoxemia on skeletal muscle oxygen supply and demand

Lowman, John D., January 1900 (has links)
Thesis (Ph.D.) -- Virginia Commonwealth University, 2004. / Title from title-page of electronic thesis. Prepared for: Dept. of Physiology. Bibliography: p. 156-178.
43

Contribuição dos sistemas energéticos na água e em diferentes ergômetros de remo / Contribution of different energy systems for rowing on the water and on different rowing ergometers

Fernando de Campos Mello 14 November 2008 (has links)
O remo é uma modalidade que depende muito das condições ambientais para ser praticada, tais como vento, chuva e frio, as quais podem atrapalhar e, dependendo da variação, até impedir a sua prática. Por esses motivos, a realização de atividades em ambiente fechado torna-se importante nesse esporte. A alternativa mais utilizada para treinamento e avaliação é o ergômetro de remo Concept2. Contudo, a dinâmica do ergômetro de remo é diferente da dinâmica na água. Na tentativa de contornar parte dos problemas associados ao uso do ergômetro, a empresa fabricante do Concept2 criou um acessório chamado slide. O objetivo do presente estudo foi verificar as respostas fisiológicas (consumo de oxigênio, freqüência cardíaca e concentração de lactato) do remador em três situações diferentes: ergômetro de remo, ergômetro de remo com o acessório slide e na água, bem como comparar a contribuição energética de cada situação. Oito sujeitos foram submetidos a cinco testes no total, sendo três deles a simulação da prova de 2000 metros em cada situação e outros dois testes progressivos até a exaustão no ergômetro de remo com e sem o slide. Os principais resultados do estudo foram: a) o perfil metabólico, bem como a demanda energética da prova de 2000m no remo é a mesma, independentemente se ela é realizada no ergômetro de remo Concept2 com ou sem slide ou na água, no barco single-skiff; b) o menor gasto energético total na água está relacionado exclusivamente ao maior tempo necessário para percorrer os 2000m nessa situação; c) a utilização do acessório slide no ergômetro de remo Concept2 não implica em alterações no perfil fisiológico da atividade; d) a utilização do ergômetro de remo no treinamento de remadores produz o mesmo efeito, no que diz respeito aos ajustes fisiológicos agudos, que o treinamento na água / Rowing is a sport that can be subject to environmental conditions as it is practiced outdoors. Wind, rain and cold climates can disturb or even impede the execution of rowing on the water. For that reason, indoor rowing is considered to be an important means of training. The most used form of indoor training and evaluation of athletes is the rowing ergometer Concept II. Nevertheless, outdoor rowing presents dynamic singularities compared to indoor rowing. In order to minimize differences related to rowing on a machine, the manufacturer of Concept II created a device called the slide. The aim of this study was to verify the physiological responses (oxygen consumption, cardiac frequency, lactate concentration) of rowers in three different situations: rowing on an ergometer without and with the slide and rowing on the water. Also, the energy contribution was evaluated. Eight individuals were submitted to five physical tests each. Three of the tests consisted of the simulation of a race in a distance of 2000m in each of the situations defined above, and 2 of the tests consisted of progressive effort until exhaustion in the rowing ergometer with and without the slide. The results obtained were the following a) metabolic profile, as well as energy demand in the 2000 m test was the same if completed on the rowing ergometer with or without the slide or on the water on a single scull. b) the least energy cost on the water was related to the longer time needed to complete the 2000 m test outdoors. C) the use of the slide on the ergometer did not show any changes on the physiological profile of the activity d) the use of the rowing ergometer for training of rowers has the same effect, in terms of physiological adjustments, as training on the water
44

The Effects of Altered Growth Hormone Signaling on Murine Metabolism

Westbrook, Reyhan Marcus 01 August 2012 (has links)
Growth hormone signaling influences longevity but the mechanism through which decreased GH action extends lifespan in mice is unknown. It is likely that the key to understanding this phenomenon, and the process of aging itself, is to understand the alterations in metabolism caused by decreased GH action. We investigated changes in energy metabolism in long-lived mice, in hope that these findings can suggest means of improving human health and longevity. These studies consisted of three projects. The influence of altered GH signaling on metabolism was tested by monitoring oxygen consumption, respiratory quotient, and heat production. Intriguingly, long-lived mice have increased oxygen consumption, and decreased respiratory quotient; while short lived mice had opposite effects. These data indicate that decreased GH signaling associates with increased metabolism per unit of body weight and may beneficially affect mitochondrial flexibility by increasing the capacity for fat oxidation; while GH excess generally produces opposite metabolic effects. We then hypothesized that the metabolic characteristics observed in young long-lived mice would persist into old age. Further, we investigated whether caloric restriction or every-other-day diet, two life extending feeding regimens, had any interaction with the metabolic phenotype observed in long-lived mice. The results support our hypothesis that the alterations in metabolism observed in young long-lived mice persist into old age. Neither dietary regimen significantly altered oxygen consumption in GHRKO mice, however, every-other-day diet reduced 24-hour oxygen consumption per gram body weight. These experiments showed that GHRKO mice had increased oxygen consumption regardless of age and life extending dietary interventions we placed them on. We hypothesized that increased oxygen consumption in long-lived mice is the result of increased thermogenesis. To test this hypothesis, we measured oxygen consumption in long-lived mice and controls at the standard lab temperature 23°C, and at 30°C, the murine thermoneutral temperature. When the oxygen consumption of long-lived mice was measured at 30°C, the differences between long-lived and normal mice measured at 23°C were abrogated. These data indicate that increased energy utilization for thermogenesis may contribute to extended longevity of these mutants. Collectively, our results provide important insights into the metabolic characteristics of long-lived mice.
45

Parâmetros antropométricos, fisiológicos e biomecânicos de nadadores em teste de 400m nado crawl : comparações e correlações

Correia, Ricardo de Assis January 2016 (has links)
Introdução e Objetivos: considerando a complexidade da natação, o objetivo geral desta dissertação foi investigar o desempenho em 400 m nado crawl (T400), a partir de parâmetros antropométricos, biomecânicos e fisiológicos. Materiais e Métodos: O estudo foi avaliado e aprovado pelo Comitê de Ética em Pesquisa da UFRGS. Participaram 14 nadadores competitivos (21,2 ± 4,15 anos de idade) de nível regional e nacional, que foram avaliados em relação à: (i) antropometria e somatotipo; (ii) parâmetros biomecânicos (frequência média de ciclos de braçadas - FB, distância média percorrida pelo corpo a cada ciclo de braçadas - DB, velocidade média de nado - VN; variação intracíclica da velocidade do centro de massa nos três eixos - VIVx, VIVy, VIVz, índice de coordenação - IdC, duração das fases propulsivas e não propulsivas - Fprop e Fnprop, e tempo propulsivo - Tprop); e (iii) parâmetros fisiológicos (consumo de oxigênio – VO2, concentração sanguínea de lactato – [LA], e percepção subjetiva de esforço – PSE). Dados foram obtidos antes, durante (M1, M2, M3 e M4) e após o T400. Parâmetros biomecânicos de nado foram obtidos por cinemetria 3D e método e-zone para cálculo da localização do centro de massa. VO2 foi mensurado respiração por respiração utilizando o ergoespirômetro K5 e esnorquel Aquatrainer (ambos Cosmed). Foi utilizada estatística descritiva e inferencial (comparativa e correlacional). Resultados: (i) nadadores de 400 m possuem somatotipo meso-ectomórfico; (ii) não houve mudanças nos parâmetros biomecânicos ao longo do teste (exceto maior FB no M4); (iii) o VO2 do M1 foi o menor em comparação a M2, M3 e M4, sendo que o maior valor de VO2 (pico: 67,6 ± 8,9 ml·kg-1·min-1) foi identificado nos últimos trechos do T400; após o termino do teste a [LA] foi de 9,03 ± 0,04 mmol.l-1 e PSE de 17,6 ± 1,2 pontos. Entre as variáveis fisiológicas, a [LA] correlacionou-se inversamente com o desempenho (r = -0,61). Conclusão: Nadadores incrementam a FB ao fim do teste, buscando, pelo menos, incrementar a VN. Mesmo que a VN tenha se mantido constante, os maiores valores foram encontrados ao final do teste. Ao mesmo tempo, o consumo de oxigênio incrementou no último quarto do teste, possivelmente de acordo com o aumento da FB. / Introduction and Objectives: considering the swimming complexity, the general objective of this study was to investigate the performance in 400 m front crawl (T400) with anthropometric, biochemical and physiological parameters. Materials and Methods: the Ethics Committee of the UFRGS approved the study. Fourteen competitive swimmers (21.2 ± 4.15 years old) of regional and national level were assessed in relation to: (i) anthropometry and somatotype; (ii) biomechanical parameters (mean rate of stroke cycles - SR, mean stroke length - SL, mean swimming speed - SS; center of mass intracyclic velocity variation in the three axes - VIVx, VIVy, VIVz; index of coordination - IdC, duration of the propulsive and non-propulsive phases - Fprop and Fnprop; and propulsive time - Tprop); and (iii) physiological parameters (oxygen consumption - VO2, blood lactate concentration - [LA], and perceived exertion - PE). Data were obtained before, during (M1, M2, M3 and M4) and after T400. Biomechanical parameters of swimming were obtained by kinematics and 3D method e-zone for calculating the center of mass location. VO2 was breath-by-breath measured using the K5 ergospirometer and snorkels Aquatrainer (both Cosmed). It used descriptive and inferential statistics (comparative and correlational). Results: (i) 400 m swimmers are meso-ectomorphic somatotype; (ii) no changes in biomechanical parameters during the test (except increased SR in the M4); (iii) VO2 in the M1 was lower when compared to M2, M3 and M4, and the largest VO2 value (peak: 67.6 ± 8.9 ml·kg-1·min-1) was identified in the last T400 part; after the end of the test the [LA] was 9.03 ± 0.04 mmol·l-1 and PE was17.6 ± 1.2 points. Among the physiological variables, [LA] correlated inversely with performance (r = -0.61). Conclusion: Swimmers increase SR in the end of the test, seeking, at least, to increase the SS. Even the VN has remained constant, the highest values were found at the end of testing. At the same time, the increased VO2 in the last in the T400’s final part possibly is in accordance with the SR increased.
46

Parâmetros antropométricos, fisiológicos e biomecânicos de nadadores em teste de 400m nado crawl : comparações e correlações

Correia, Ricardo de Assis January 2016 (has links)
Introdução e Objetivos: considerando a complexidade da natação, o objetivo geral desta dissertação foi investigar o desempenho em 400 m nado crawl (T400), a partir de parâmetros antropométricos, biomecânicos e fisiológicos. Materiais e Métodos: O estudo foi avaliado e aprovado pelo Comitê de Ética em Pesquisa da UFRGS. Participaram 14 nadadores competitivos (21,2 ± 4,15 anos de idade) de nível regional e nacional, que foram avaliados em relação à: (i) antropometria e somatotipo; (ii) parâmetros biomecânicos (frequência média de ciclos de braçadas - FB, distância média percorrida pelo corpo a cada ciclo de braçadas - DB, velocidade média de nado - VN; variação intracíclica da velocidade do centro de massa nos três eixos - VIVx, VIVy, VIVz, índice de coordenação - IdC, duração das fases propulsivas e não propulsivas - Fprop e Fnprop, e tempo propulsivo - Tprop); e (iii) parâmetros fisiológicos (consumo de oxigênio – VO2, concentração sanguínea de lactato – [LA], e percepção subjetiva de esforço – PSE). Dados foram obtidos antes, durante (M1, M2, M3 e M4) e após o T400. Parâmetros biomecânicos de nado foram obtidos por cinemetria 3D e método e-zone para cálculo da localização do centro de massa. VO2 foi mensurado respiração por respiração utilizando o ergoespirômetro K5 e esnorquel Aquatrainer (ambos Cosmed). Foi utilizada estatística descritiva e inferencial (comparativa e correlacional). Resultados: (i) nadadores de 400 m possuem somatotipo meso-ectomórfico; (ii) não houve mudanças nos parâmetros biomecânicos ao longo do teste (exceto maior FB no M4); (iii) o VO2 do M1 foi o menor em comparação a M2, M3 e M4, sendo que o maior valor de VO2 (pico: 67,6 ± 8,9 ml·kg-1·min-1) foi identificado nos últimos trechos do T400; após o termino do teste a [LA] foi de 9,03 ± 0,04 mmol.l-1 e PSE de 17,6 ± 1,2 pontos. Entre as variáveis fisiológicas, a [LA] correlacionou-se inversamente com o desempenho (r = -0,61). Conclusão: Nadadores incrementam a FB ao fim do teste, buscando, pelo menos, incrementar a VN. Mesmo que a VN tenha se mantido constante, os maiores valores foram encontrados ao final do teste. Ao mesmo tempo, o consumo de oxigênio incrementou no último quarto do teste, possivelmente de acordo com o aumento da FB. / Introduction and Objectives: considering the swimming complexity, the general objective of this study was to investigate the performance in 400 m front crawl (T400) with anthropometric, biochemical and physiological parameters. Materials and Methods: the Ethics Committee of the UFRGS approved the study. Fourteen competitive swimmers (21.2 ± 4.15 years old) of regional and national level were assessed in relation to: (i) anthropometry and somatotype; (ii) biomechanical parameters (mean rate of stroke cycles - SR, mean stroke length - SL, mean swimming speed - SS; center of mass intracyclic velocity variation in the three axes - VIVx, VIVy, VIVz; index of coordination - IdC, duration of the propulsive and non-propulsive phases - Fprop and Fnprop; and propulsive time - Tprop); and (iii) physiological parameters (oxygen consumption - VO2, blood lactate concentration - [LA], and perceived exertion - PE). Data were obtained before, during (M1, M2, M3 and M4) and after T400. Biomechanical parameters of swimming were obtained by kinematics and 3D method e-zone for calculating the center of mass location. VO2 was breath-by-breath measured using the K5 ergospirometer and snorkels Aquatrainer (both Cosmed). It used descriptive and inferential statistics (comparative and correlational). Results: (i) 400 m swimmers are meso-ectomorphic somatotype; (ii) no changes in biomechanical parameters during the test (except increased SR in the M4); (iii) VO2 in the M1 was lower when compared to M2, M3 and M4, and the largest VO2 value (peak: 67.6 ± 8.9 ml·kg-1·min-1) was identified in the last T400 part; after the end of the test the [LA] was 9.03 ± 0.04 mmol·l-1 and PE was17.6 ± 1.2 points. Among the physiological variables, [LA] correlated inversely with performance (r = -0.61). Conclusion: Swimmers increase SR in the end of the test, seeking, at least, to increase the SS. Even the VN has remained constant, the highest values were found at the end of testing. At the same time, the increased VO2 in the last in the T400’s final part possibly is in accordance with the SR increased.
47

Efficacy of the homeopathic simplex Arsenicum album 200CH in improving oxygen consumption during sub-maximal cycling

Ramsay, Cassandra 01 May 2013 (has links)
M.Tech. (Homoeopathy) / The ability to consume oxygen during exercise relies on the functionality of the cardiorespiratory system to deliver oxygen to the working muscles and therefore generate ATP or energy (Astrand et al., 2003). Performance enhancement drugs are becoming increasingly popular as athletes are under extreme pressure to enhance their performance (Shermer, 2008). The purpose of this study was to look for a safe alternative to increase oxygen consumption during exercise. The aim included determining whether the homeopathic remedy Arsenicum album 200CH had an effect on oxygen consumption during submaximal cycling. The study consisted of 32 healthy participants who were randomly divided into a control (placebo) or experimental (treatment) group. Two baseline tests were performed where no medication (remedy or placebo) was given two days apart and the average of the two were taken as the baseline average. After a further two days, the first medication test was conducted after participants were given the treatment 5 minutes prior to testing to ascertain the immediate effect of the medication. The last test was performed after one week of administering where the medication was given twice daily to distinguish what the prolonged effect of the medication was on oxygen consumption. The test consisted of a warm-up at 25-Watts for women and 50-Watts for men, the test included cycling at 3 minute increments where the wattage was increased every 3 minutes by 25-Watts until the participants reached their age-predicted maximum. When this maximum was reached, the wattage was decreased to the warm-up wattage and a cool-down commenced. Heart rate was recorded every minute and documented. The participant was also asked to rate their perceived rate of exertion at the end of every 3minute stage, as a subjective measurement. Although the time periods of administration yielded different results, both were statistically insignificant. The immediate administration showed a negative trend whereas the prolonged administration showed a positive trend in the treatment group after one week. Despite not showing statistical significance, it warrants additional research over a longer period of time.
48

Using Macroinvertebrates to Assess the Effects of Nutrient Input Between the Nolichucky and Pigeon Rivers

Grizzard, Anna 01 May 2022 (has links)
Previous work found significant differences in growth rates of native mussels at locations downstream from the regulated Walter’s Dam and the out-of-service, free-flowing Davy Crockett Dam. The purpose of this study is to investigate differences within the macroinvertebrate communities related to factors driving the differences in mussel growth between rivers. Macroinvertebrate samples were collected following the Tennessee Department of Environment and Conservation protocol for SQKICK collection and analyzed using the Tennessee Macroinvertebrate Index (TMI). There were no significant differences in TMI scores between the downstream sites of the rivers, but there were significant increases in chlorophylla, dissolved oxygen, and specific conductance downstream compared to upstream in both rivers. This suggests that these indices are suitable to identify pollution changes, but potentially not the productivity differences that impacted mussel growth.
49

Effects of Salinity on Growth, Oxygen Consumption Rate and Ion Regulation in Two Ages of Alligator Gar Atractosteus Spatula

Schwarz, Daniel Edwin 12 May 2012 (has links)
The alligator gar Atractosteus spatula is a euryhaline fish found in the Gulf of Mexico and surrounding drainages. However, the extent of its hypo-osmotic abilities are not well understood. To determine effect of salinity on growth, metabolic rate, and osmoregulation abilities the following question was developed: when does the alligator gar have the osmoregulatory capabilities to survive in hyperosmotic environments? To answer this question, two different age groups (60 and 330 days after hatch [DAH]) of juvenile alligator gar were exposed to 4 different salinities (0, 8, 16, and 24 ppt) for a 30-day period. Specific growth rate, oxygen consumption rate, plasma osmolality, plasma ion concentrations, tissue Na+, K+-ATPase activities, and drinking rate were measured. I determined that the 60 DAH alligator gar had a greater ability to grow and regulate ions than did the 330 DAH alligator gar in increased salinity.
50

The Influence of Incubation Conditions on Oxygen Consumption During the Development of Pantherophis guttatus

Gallardo, Celeste 01 August 2021 (has links)
The flexible shell of some oviparous reptiles has led to differences in nutrient mobilization and water relations when compared to their rigid-shelled counterparts. Flexible-shelled eggs gain more water during development, and because of the shell structure, yolk calcium content is higher than that of eggshells. When water availability is altered for reptiles with flexible-shelled eggs, differences in both energy and nutrient utilization are observed. This study was designed to determine the baseline metabolic rate during development for the snake, Pantherophis guttatus under normal conditions, and to observe how changes in eggshell calcium and water availability impact embryonic oxygen consumption. Eggshell calcium was decreased while water uptake was increased by removing the outer calcareous eggshell layer from some eggs. When eggs are left intact, an exponential increase in oxygen consumption is observed, supporting previous studies, while removal of the eggshell produces no effect on metabolism.

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