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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.
251

EFFECT OF BODY MASS INDEX ON POST-EXERCISE HEMODYNAMIC RESPONSES

Moore, Stephanie M. 01 January 2014 (has links)
To assess the relationships of body mass index (BMI) on arterial stiffness at rest and post-maximal treadmill graded exercise testing (GXT). Forty-four apparently healthy, young adult males (22.1 ± 0.48 years) were recruited and divided into either a healthy weight (H, ≤24.9 kg/m2), overweight (OV, 24.9-29.9 kg/m2) or obese (OB, ≥29.9 kg/m2) group based on BMI. All subjects underwent arterial stiffness (carotid-femoral pulse wave velocity, cfPWV), blood pressure (BP), pulse pressure (PP), mean arterial pressure (MAP) and body composition (bioelectrical impedance analysis, BIA) measurements at rest. Following the GXT, measures of arterial stiffness (cfPWV) and BP were acquired. Resting measures of cfPWV, BMI, systolic BP, diastolic BP, MAP, and PP were significantly (p <0.05) greater in OV and OB compared with H. Compared with OV, OB had a greater BMI. Relative peak oxygen consumption (VP2peak) was greater in H compared with OV and OB (p<0.05). systolic BP was positively associated, whereas VO2peak was inversely related to cfPWV (p<0.05). No significant inter-group interactions were observed with cfPWV after the GXT. However, interactions were observed for SBP, DBP and PP (p<0.05). In young men with varying BMI, SBP and VO2peak were associated with resting cfPWV. However, similar cardiovascular responses were observed between groups after a maximal GXT.
252

Espaces $(L^{q},\ell^{p})^{\alpha}(G)$ sur un groupe de type homogène et continuité de l'intégrale fractionnaire.

Feuto, Justin 25 October 2003 (has links) (PDF)
Nous généralisons dans le cadre de groupe localement compact non necessairement abélien, une famille d'espaces de Banach qui sont entre autres des sous-espaces d'espaces d'amalgames de Wiener admettant une dilatation isométrique, et sous-espaces d'espaces de Morrey. Sur ces espaces, nous établissons des inégalités à poids pour l'opérateur maximal fractionnaire et l'intégrale fractionnaire.
253

Class degree and measures of relative maximal entropy

Allahbakhshi, Mahsa 16 March 2011 (has links)
Given a factor code [pi] from a shift of finite type X onto an irreducible sofic shift Y, and a fully supported ergodic measure v on Y we give an explicit upper bound on the number of ergodic measures on X which project to v and have maximal entropy among all measures in the fiber [pi]-1{v}. This bound is invariant under conjugacy. We relate this to an important construction for finite-to-one symbolic factor maps.
254

Computational Representation Of Protein Sequences For Homology Detection And Classification

Ogul, Hasan 01 January 2006 (has links) (PDF)
Machine learning techniques have been widely used for classification problems in computational biology. They require that the input must be a collection of fixedlength feature vectors. Since proteins are of varying lengths, there is a need for a means of representing protein sequences by a fixed-number of features. This thesis introduces three novel methods for this purpose: n-peptide compositions with reduced alphabets, pairwise similarity scores by maximal unique matches, and pairwise similarity scores by probabilistic suffix trees. New sequence representations described in the thesis are applied on three challenging problems of computational biology: remote homology detection, subcellular localization prediction, and solvent accessibility prediction, with some problem-specific modifications. Rigorous experiments are conducted on common benchmarking datasets, and a comparative analysis is performed between the new methods and the existing ones for each problem. On remote homology detection tests, all three methods achieve competitive accuracies with the state-of-the-art methods, while being much more efficient. A combination of new representations are used to devise a hybrid system, called PredLOC, for predicting subcellular localization of proteins and it is tested on two distinct eukaryotic datasets. To the best of author&rsquo / s knowledge, the accuracy achieved by PredLOC is the highest one ever reported on those datasets. The maximal unique match method is resulted with only a slight improvement in solvent accessibility predictions.
255

最大,二分,外平面圖之容忍表示法 / The Tolerance Representations of Maximal Bipartite Outerplanar Graphs

賴昱儒 Unknown Date (has links)
在這篇論文中,我們針對2-連通的最大外平面圖而且是二分圖的圖形,討論 其容忍表示法,並找到它的所有禁止子圖H1、H2、H3、H4。 / In this thesis, we prove a 2-connected graph G which is maximal outerplanar and bipartite is a tolerance graph if and only if there is no induced subgraphs H1; H2; H3 and H4 of G.
256

Efeito do nível do treinamento aeróbio na determinação do limite superior do domínio pesado no ciclismo /

Caritá, Renato Aparecido Corrêa. January 2011 (has links)
Orientador: Camila Coelho Greco / Banca: Fabrizio Caputo / Banca: Dalton Muller Pessoa Filho / Resumo: O principal objetivo deste estudo foi analisar e comparar as respostas metabólicas e cardiorrespiratórias durante o exercício realizado na MLSS e PC em indivíduos com diferentes níveis de treinamento aeróbio no ciclismo. Participaram do estudo 7 ciclistas (C) bem treinados, especializados em provas de estrada e 9 sujeitos não treinados (NT), sem experiência prévia de treinamento no ciclismo. Os voluntários realizaram em dias diferentes os seguintes testes, em um cicloergômetro: 1) teste incremental até a exaustão para a determinação do limiar anaeróbio (Lan), consumo máximo de oxigênio ( O2max) e da intensidade correspondente ao O2max (I O2max); 2) 2 a 4 testes de carga constante de 30 minutos em diferentes intensidades para a determinação da máxima fase estável de lactato sanguíneo (MLSS); 3) 3 testes de carga constante a 95, 100 e 110% I O2max até a exaustão voluntária para a determinação da potência crítica (PC), e; 4) um teste de carga constante até a exaustão na PC. A MLSS foi considerada como a maior intensidade de exercício onde a concentração de lactato não aumentou mais do que 1 mM entre o 10o e o 30o minuto de exercício. Os valores individuais de potência (95, 100 e 110% I O2max) e seu respectivo tempo máximo de exercício (tlim) foram ajustados a partir do modelo hiperbólico de 2 parâmetros para determinação da PC. A PC para ambos os grupos C (318 ± 29W) e NT (200 ± 33W) foi maior significantemente do que a MLSS para os C (288 ± 35W) e NT (169 ± 34W). A MLSS e a PC foram significantemente maiores no grupo C. Em valores relativos ao O2max a MLSS foi maior no grupo C (83 ± 7%) do que no grupo NT (79 ± 6), porém a PC foi similar entre os grupos (91 ± 5% e 90 ± 5%, respectivamente). Da mesma forma, o consumo de oxigênio na PC ( O2PC) foi significantemente maior do que na MLSS ( O2MLSS) nos grupos NT... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to analyze and to compare metabolic and cardiorrespiratory responses durin the exercise performed at MLSS and CP in subjects with different aerobic trainning levels in cycling. Participated of this study, 7 well trained cyclists (C), specialized in road events and 9 non-trained subjects (NT), without previous training experience in cycling. Ths subjects performed the following protocols in different days in cyclergometer: 1) incremental test until exhaustion to determine anaerobic threshold (AT), maximal oxygen uptake ( O2max) and the intensity at O2max (I O2max); 2) 2 to 4 constant workload tests in different intensities to determine maximal lactate steadystate (MLSS); 3) 3 constant workload tests at 95, 100 e 110% I O2max until exhaustion to determine critical power (CP), and; 4) constant workload test until exhaustion at CP. MLSS was considered the highest exercise intensity at which the blood lactate concentration did not increase for more than 1 mM between 10th and 30th minute of the exercise. The individual values of power (95, 100 e 110% I O2max) and the respective times (tlim) were adjusted using the hyperbolic model with parameteres to determine CP. CP for C (318 ± 29W) and NT (200 ± 33W) was significantly higher than MLSS in C (288 ± 35W) and NT (169 ± 34W). MLSS and PC were significantly higher in C group. In values relative to O2max, the MLSS was significantly higher in C (83 ± 7%) than NT (79 ± 6), however CP was similar between groups (91 ± 5% and 90 ± 5%, respectively). In the same way, the oxygen uptake at CP ( O2PC) was significantly higher than at MLSS ( O2MLSS) for NT (2627 + 519 e 2323 ± 460 mL.min-1, 11%) e C (3607 ± 505 e 3953 ± 466 mL.min-1, 8%). The slow component at CP in C (375 ± 164 ml.min-1) was similar to NT (412 ± 175 ml.min-1). At this condition, the O2max was not attained (C - 93 ± 5%; NT - 96 ± 7%)... (Complete abstract click electronic access below) / Doutor
257

Safety evaluation of low level light therapy on cancer cells

Jeong, Andrew S. 15 June 2016 (has links)
OBJECTIVE: Low level light therapy (LLLT) is being widely used in wound healing and pain relief, and its use is expected to be expanded rapidly to treatment of other disorders as well in a foreseeable future. However, before its expansion, the fear that LLLT could initiate or promote metastasis must be addressed thoroughly. As an initial effort towards this end, the current study evaluates the safety of LLLT in vitro using two different human cancer cell lines (Michigan Cancer Foundation-7 (MCF-7) and Jurkat E6-1) by determining the viability of cells after low level light (LLL) application while treatment under anti-cancer chemotherapeutic drugs (5-fluorouracil (5-FU) and cisplatin) separately on each cell line. METHODS: Two human cancer cell lines (MCF-7 and Jurkat E6-1) were cultured throughout the experiments. Two different anti-cancer chemotherapeutic drugs (5-FU and cisplatin) were used to treat both cell lines. The half maximal inhibitory concentration (IC50) of each drug on each cell line was determined by treating each cell line with varying concentrations of each drug. A total of 3 or 4 trials were done for each cell line with each drug, and the range of concentration was narrowed closer to the IC50 value at each successive trial. Once the IC50 concentrations were determined, each cell line was treated with 808 nm LLL at varying energy densities in a single dose using a light emitting diode (LED) source both in the absence and the presence of each drug at one IC50. A total of 3 or 5 trials were done for each cell line with each drug, and for each trial, six different energy densities ranging from 0 J/cm2 (control) to 10 J/cm2 were applied. The energy densities were varied for each trial with control always being used. After application of LLL, the viability of cells was determined, and three different 1-way ANOVA (Analysis of Variance) analyses were done to compare the viability of cells at each energy density to that of control. RESULTS: The IC50 of 5-FU in MCF-7 and Jurkat E6-1 cells was determined as 70 µM and 20 µM respectively. The IC50 of cisplatin in MCF-7 and Jurkat E6-1 cells was determined as 17 µM and 7 µM respectively. No significant difference (P > 0.05) in the viability of MCF-7 cells was observed between each group treated with different energy density of LLL and control group (0 J/cm2) both in the absence and the presence of 5-FU at IC50 (70 µM). No significant difference (P > 0.05) in the viability of MCF-7 cells was observed between each group treated with different energy density of LLL and control group (0 J/cm2) both in the absence and the presence of cisplatin at IC50 (17 µM). No significant difference (P > 0.05) in the viability of Jurkat E6-1 cells was observed between each group treated with different energy density of LLL and control group (0 J/cm2) both in the absence and the presence of 5-FU at IC50 (20 µM). However, a significant increase (0.01 < P < 0.05) in the viability of cells was observed when treating Jurkat E6-1 cells with 10 J/cm2 of LLL in the presence of cisplatin at IC50 (7 µM) compared to control group (0 J/cm2). Except for the comparison mentioned previously, no significant difference in the viability of Jurkat E6-1 cells was observed between each group treated with different energy density of LLL and control group (0 J/cm2) both in the absence and the presence of cisplatin at IC50 (7 µM). No definite trend in the viability of cells was observed with increasing energy density of LLL for each cell line either in the absence of the presence of each drug at IC50. CONCLUSIONS: The application of LLL at 808 nm with energy densities ranging from 0.1 J/cm2 to 10 J/cm2 under an LED source did not induce cell proliferation or death compared to control (0 J/cm2) for each cell line in the absence or the presence of each drug, and no definite trend was observed with increasing energy density. The study suggests that LLLT at these parameters may be safe to use on cancer patients, but further studies on different cancer cell lines and animal models with different parameters (wavelength, energy density, dosage) of LLL are warranted.
258

Neuromechanics of explosive performance for movement control and joint stabilisation

Behan, Fearghal January 2017 (has links)
The broad aim of this thesis was to progress understanding of the neuromechanics of joint stability and injury mechanisms by investigating the interactions between neuromuscular function and balance perturbations as well as the influence of sex and fatigue on these variables. Knee extensor (KE) and plantar flexor (PF) isometric strength parameters (maximum voluntary torque (MVT), explosive voluntary torque (EVT)) were related in young healthy adults. EVT of KE and PF were correlated at 4/5 time points during the rising torque-time curve for all absolute (r = 0.488-0.755) and relative (to body mass (BM) (r = 0.517-0.669) and MVT (r = 0.353-0.480)) expressions of EVT. These results suggest that KE and PF function is related for both maximum and explosive torque. Males were stronger for KE (+89%) and PF (+55%) than females. Males also displayed greater EVT at all time points in KE (+57-109%) and at 50-150 ms in PF (+33-52%). When MVT and EVT were normalised to BM, males continued to be stronger at all time points in KE (+23-60%) and from 100-150 ms (18-20%) in PF. No sex differences were found when EVT was normalised to MVT. Furthermore, sex differences were discovered in muscle morphology. Females had a smaller knee flexor (KF):KE size ratio, a proportionately small sartorius (SA) and gracilis (GR) and a proportionately larger vastus lateralis (VL), potentially predisposing females to greater risk of ACL injury. Females had a larger biceps femoris long head (BFlh) as a proportion of the KF than males, which may contribute to the higher risk of hamstring strain injury (HSI) in males. Regarding explosive performance and perturbation response, explosive PF torque had a weak to moderate correlation with COM displacement (COMD) from 400-500 ms (r = -0.346 to -0.508) and COM velocity (COMV) from 300-500 ms (r = -0.349 to -0.416), with weaker correlations between explosive KE torque and COMV at 400 ms (r = -0.381 to -0.411) but not with COMD. These findings suggest that greater explosive torque results in better control of the COM in response to unexpected perturbations. The effects of football simulated fatigue on these factors resulted in reduced maximal KF and KE torque. However, football simulated fatigue was not found to reduce EVT of either muscle group, or explosive H/Q ratio. Football simulated fatigue resulted in impaired balance response to unexpected perturbation in the posterior but not the anterior direction.
259

Ensaio clínico randomizado de uma intervenção educacional no exercício físico e na qualidade de vida de crianças e adolescentes com fibrose cística

Hommerding, Patrícia Xavier January 2011 (has links)
Objetivos: O exercício físico regular em pacientes com fibrose cística (FC) auxilia no condicionamento aeróbico e diminui a progressão da doença, proporcionando melhor qualidade de vida. O objetivo desse estudo foi avaliar os efeitos de um programa de exercício físico aeróbico baseado na orientação verbal e instrumental na capacidade funcional e na qualidade de vida. Métodos: O Estudo constituiu-se de um ensaio clínico, randomizado, de orientações para o exercício físico realizado em um centro de FC. Os pacientes foram alocados em dois grupos, intervenção e controle, sendo 17 pacientes no grupo intervenção (G1) e 17 para o grupo controle (G2). A coleta de dados ocorreu durante o período de outubro de 2010 a outubro de 2011, e a população em estudo consistiu em crianças e adolescentes com FC e idade entre sete e 20 anos.A intervenção foi um manual de orientações com exercícios físicos aeróbicos e reforço das orientações por meio de contato telefônico a cada duas semanas. Resultados: Foram estudados 34 pacientes com FC, sendo que 20 pacientes (58,8)% eram do sexo masculino. Os grupos eram semelhantes no momento basal, sendo que no G1 seis pacientes (35,2%) referiram praticar exercício físico regularmente, a média de idade foi de 13,40±2,81 anos, do percentual do previsto do volume expiratório forçado no primeiro segundo (VEF1%) foi de 95,53±17,94 % e do consumo de oxigênio de pico relativo a massa corporal (VO2pico) foi de 34,93±9,09 ml/kg-1.min-1 . No G2, quatro pacientes (23,5%) referiram praticar exercício físico regularmente, a média de idade foi de 12,76±3,37 anos, do VEF1 foi de 100,13±21,27 % e do VO2pico foi de 33,21±8,26 ml/kg-1.min. Houve aumento significativo do G1 na prática de exercício físico relatada pelos pacientes após os três meses de intervenção comparado ao G2 (p=0,013). Nas demais variáveis não foram observadas diferenças estatisticamente significativas. Conclusão: Esse estudo demonstrou que a orientação verbal e instrumental para o exercício aeróbico, acoplado com supervisão telefônica teve impacto positivo no relato das crianças e adolescentes quanto a prática do exercício físico regular. Porém, não foram observados melhora nos parâmetros fisiológicos, nem nos domínios do questionário de qualidade de vida. / Objectives: Regular physical activity in patients with cystic fibrosis (CF) improves aerobic conditioning and delays disease progression, which results in better quality of life. This study evaluated the effect on functional capacity and quality of life of an aerobic physical activity program based on verbal and written guidelines. Methods: This randomized clinical trial used guidelines for physical exercise in a CF center. Patients were assigned to two groups: intervention (G1), with 17 patients; and control (G2), also with 17 patients. Data were collected from October 2010 to October 2011, and the study population comprised children and adolescents with CF aged 7 to 20 years. The intervention consisted of handing out a manual with guidelines for aerobic physical exercises and reinforcing recommendations in contacts by phone every two weeks. Results: Thirty-four patients were included in the study, 20 of whom were boys (58.5%). The groups were similar at baseline. In G1, 6 patients (35.2%) reported practicing physical exercises regularly; mean age was 13.40±2.81 years, mean percent predicted forced expiratory flow at one second (FEV1%) was 95.53±17.94% and mean peak oxygen uptake (VO2peak) relative to body mass was 34.93±9.09 ml/kg-1.min-1. In G2, four patients (23.5%) reported practicing physical exercises regularly. Mean age was 12.76±3.37 years, mean FEV1 was 100.13±21.27% and mean VO2peak was 33.21±8.26 ml/kg-1.min. In G1, there was a significant increase of physical exercise practice as reported by patients after three months of intervention when compared with G2 (p=0.013). No statistically significant differences were found for the other variables. Conclusion: Verbal and written guidelines for aerobic exercise, together with supervision over the phone, had a positive impact on the report of regular physical exercise practice by children and adolescents. However, no improvement was found in physiological parameters or domains of the quality of life questionnaire.
260

Manipulating exercise and recovery to enhance adaptations to sprint interval training

Taylor, Conor W. January 2017 (has links)
Highly-trained athletes are accustomed to varied and high-volume based exercise stimuli and eliciting adaptation in individuals already possessing the necessary physiology to compete at the highest level is difficult. Therefore, identifying novel, potent and time efficient methods of achieving cumulative training stress is a continual quest for coaches and exercise scientists. This thesis examined the acute and chronic effects of manipulating exercise and recovery during brief all-out sprint cycling on adaptive responses favouring enhanced endurance capacity. Chapter 3 highlighted that low-volume non-work matched all-out sprint cycling, whether it be interval- (4 x 30 s bouts) or continuous based (1 x 2 min bout) provides a similarly potent stimulus for the acute induction of cell signalling pathways and key growth factors associated with mitochondrial biogenesis and angiogenesis in trained individuals. In line with manipulating recovery and in attempting to identify a novel and potent exercise intervention capable of giving athletes more return on their training investment, Chapters 4-6 investigated the efficacy of combining sprint interval training with post-exercise blood flow restriction (BFR). Firstly, it was demonstrated that BFR potentiates HIF-1α mRNA expression in response to SIT, tentatively suggesting an enhanced stimulus for hypoxia- and/or metabolic-mediated cell signalling associated with mitochondrial biogenesis and angiogenesis over SIT alone. Secondly, four weeks of SIT combined with post-exercise BFR provides a greater training stimulus over SIT alone in trained individuals to enhance VO2max (4.7 v 1.1 % change) and MAP (3.8 v 0.2 % change), but not 15-km TT performance. Finally, in response to four weeks of SIT combined with post-exercise BFR, an international female track sprint cyclist increased her CP and W by 7 and 2 % and VO2max and absolute MAP by 3 and 4 %, respectively. Through a combination of an acute in vivo molecular experiment, a training study and an athlete case study, this thesis has introduced a potentially potent and novel training concept that appears capable of augmenting aerobic capacity.

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