Master of Science - Science / The theoretical investigation of the Optical Kerr Effect (OKE) and Third- Harmonic Generation (THG) of Au-VO2 nanocomposite thin-films undertaken in this project is motivated by the potential use of the Au-VO2 nanocomposite in nonlinear optical (NLO) devices. NLO devices are a driving force in today fs high technology industry. In this thesis the OKE is estimated and computed and will be compared later to the measured OKE using the Z-scan interferometric laser technique [47]. This is a simple yet highly sensitive single-beam experimental technique used to determine the real part of the dielectric susceptibility. The study of the OKE in these composites has shown that it has a high value, comparable to that found in Au-SiO2, Au-TiO2 and Au-Al2O3 thin-films [29, 33]. This is despite the fact that the Au volumetric concentration in the Au-VO2 composites considered here is 10 percent at most, whereas in the other above mentioned composite thin-films the volumetric concentration range was between 5 − 60 percent. Moreover, it has been demonstrated that the OKE is thermally tunable in the Au-VO2 thin-films, owing to the thermally tunable optical properties of the VO2 [8, 38]. It is found that the magnitude of the OKE is of the order of 10−6 esu when the composite is below 68 0C and it is of the order of 10−7 esu when the nanocomposite thin-film is above 68 0C. The large enhancement of the OKE is due to the surface plasmon resonance (SPR) of the nanogold particles. Its fast response, which is of the order of few picoseconds [4, 6, 7], makes the Au-VO2 nanocomposite a good candidate as a fast thermally tunable optical switch or modulator. The modelling here of high-order harmonic generation in strongly absorbing media, as regards the amplitude of the primary beam, takes into account pump attenuation only, due to the absorption of light by the media. It is not concerned with pump depletion which is a consequence of the transfer of energy to the harmonics and which is small by comparison with attenuation in absorbing media. The modelling is applied to the so-called transmission and reflection configurations. The former refers to the case in which the high-order harmonic wave is monitored in the same direction as the input fundamental wave, whereas the latter describes the situation in which the fundamental wave is in the opposite direction to the high-order harmonic one. To analyse high-order harmonic generation one has to relate the high-order harmonic intensity to the fundamental intensity [1, 9, 10, 34-36]. In so doing, a general formula for analysing high-order harmonic generation is obtained and reduced to the particular case pertaining to THG in strongly absorbing media. The ratio of the third-harmonic intensity to the fundamental intensity is termed the conversion coefficient or the conversion efficiency, and it is denoted by ƒÅ [23, 34]. It is useful in the sense that it expresses quantitatively the amount of input light of frequency ƒÖ converted into light of frequency nƒÖ, where n is the order of nonlinear polarisation [1]. It is found that the THG conversion coefficient is higher the higher the laser intensity. It is thus advantageous to use a pulsed laser, which achieved very high intensities for short periods, separated by long off periods. The net harmonic output in this case is much higher than one would obtain with a continous laser of the same average output. It is found here that ƒÅ is greater in the reflection configuration compared to the transmission one above and below Tt in the photon energy range 1.0 − 3.0 eV, see Fig. 5.1 to 5.8. However, the conversion efficiency for THG in the Au-VO2 nanocomposites for the picoseconds laser illumination we have considered, is still extremely low, and it is difficult to see a potential use for this system as a tunable frequency converter. The situation would become more favorable with the use of femtosecond laser pulses, where for the same pulse energy the intensity is much greater. The laser pulse energy must be limited to avoid excessive heating of the thin-film. The heat generated as a consequence of the illumination of the thin-film by the laser [23] may be controlled by using a simple cooling device which consists of a substrate on which the thin-film is deposited. The choice of such a substrate depends on whether THG is monitored in the transmission or reflection configuration. In the former a transparent substrate must be used (for example diamond) whereas in the latter an opaque substrate may be used (for example Ag). Calculations pertaining to the removal of heat from the illuminated film are reported, and show that thermal control is manageable but only within limits. To avoid a temperature rise of more than 5 0K the peak laser intensity we found must not exceed 7.4 ~105Wcm−2 with a pulse duration of 5 ps.

<p>Inaktivitet i samhället ökar, och en av konsekvenserna för detta är att allt flera lider av övervikt och fetma. Andelen överviktiga barn i USA, Europa och Australien har ökat 2-3 gånger under de senaste 25 åren. I denna studie undersöktes kondition och aktivitetsvanor hos årskurs 7 och 8 mellan en glesbygdskola och en tätortskola. 16 elever från varje skola deltog i studien, 8 av varje kön. Enkät och Åstrand steptest användes. Resultatet visar att det inte fanns någon skillnad mellan en tätortskola och en glesbygdskola vad gäller konditionsvärden. Avseende enkätsvaren framkom att en något större andel glesbygdseleverna är medlem i en idrottsförening jämfört med tätortseleverna, samt att glesbygdens elever saknade olika fritidsaktiviteter. I denna studie fann man ingen betydelse om man som 14-15 åring går på en skola i glesbygden jämfört med en skola i tätorten vad gäller konditionsnivå.</p>

Dans ce mémoire, j'étudie la physique des milieux denses, plasmas ou solides, en utilisant la spectroscopie d'absorption de rayonnement X. Au moyen de sources produites par interaction laser-matière, nous avons mesuré les spectres d'absorption de plasmas d'aluminium et brome, ainsi que ceux du dioxyde de vanadium (VO2). Les mesures des co-efficients d'absorption permettent de sonder la matière dense et d'étudier ses propriétés. Les expériences sont réalisées suivant le même principe : elles utilisent un schéma expérimental identique, appelé pompe-sonde. Lorsque que la matière est dense, l'absorption d'un atome est modifiée par le milieu environnant. Dans un plasma, ce sont principalement les transitions lié-lié qui sont influencées : les profils des raies spectrales sont modifiés. Dans un solide, les positions des atomes voisins de l'atome absorbeur modifient la structure des seuils d'absorption (transition lié-libre). L'étude de cette structure permet de mesurer les paramètres du matériau, et donne des informations comme l'état des bandes électroniques ou encore les distances interatomiques. Les expériences réalisées au LULI ont permis de sonder des plasmas dans le régime mal connu de la Warm Dense Matter. Un des paramètres clés, est que le plasma est caractérisé de manière indépendante (diagnostic FDI). Cela permet une meilleure comparaison de l'absorption mesurée avec un calcul réalisé avec le modèle numérique OPA-S. Les expériences réalisées à l'INRS ont mené à la réalisation d'un système expérimental ayant les caractéristiques permettant l'étude de la dynamique de solides présentant des transitions de phase ultra- rapide. Pour cela, nous avons utilisé le dioxyde de vanadium comme système modèle permettant de tester la faisabilité de la méthode.

Inaktivitet i samhället ökar, och en av konsekvenserna för detta är att allt flera lider av övervikt och fetma. Andelen överviktiga barn i USA, Europa och Australien har ökat 2-3 gånger under de senaste 25 åren. I denna studie undersöktes kondition och aktivitetsvanor hos årskurs 7 och 8 mellan en glesbygdskola och en tätortskola. 16 elever från varje skola deltog i studien, 8 av varje kön. Enkät och Åstrand steptest användes. Resultatet visar att det inte fanns någon skillnad mellan en tätortskola och en glesbygdskola vad gäller konditionsvärden. Avseende enkätsvaren framkom att en något större andel glesbygdseleverna är medlem i en idrottsförening jämfört med tätortseleverna, samt att glesbygdens elever saknade olika fritidsaktiviteter. I denna studie fann man ingen betydelse om man som 14-15 åring går på en skola i glesbygden jämfört med en skola i tätorten vad gäller konditionsnivå.

Les difficultés respiratoires chez les blessés médullaires (BM) nuisent à leur qualité de vie. Le fonctionnement des muscles respiratoires (MR) chez les blessés médullaires (BM) est dépendant du niveau de la lésion à la moelle épinière. Le but de cette étude est de déterminer la consommation en oxygène des muscles respiratoires (VO2MR) durant une épreuve inspiratoire progressive chez les BM. Un groupe de 6 participants tétraplégiques (C4-C7) et un groupe témoin (GT) de 10 participants ont été recrutés pour effectuer une épreuve inspiratoire à l'aide d'une valve Hans-Rudolph modifiée. Avant l'épreuve, la capacité vitale lente, les pressions inspiratoire et expiratoire maximales (PImax et PEmax) ont été mesurées. Durant le test progressif, la pression inspiratoire à la bouche (PiB) augmentait à chaque palier de deux minutes. La progression des charges était de 0g, 50g, 100g et 200g (~20cmH2O). La VO2MR a été mesurée à chaque palier et la fréquence respiratoire a été imposée à 12 respirations par minute. Dans les deux groupes, la VO2RM a augmenté linéairement en fonction du %PImax (BM, r=0.96, p=0.03 et GT, r=0.97, p=0.04) et a tendance à être plus faible chez les participants BM que ceux des participants GT (intersection y, 257±9,4 et 307±10,8 ml*min-1, et la pente, 2.92±0.6 et 4.27±0.8 ml*min-1*%PImax-1, respectivement). Toutefois, nous n'avons pu atteindre une différence significative entre les deux groupes pour la VO2MR (F(l4,1)=3,7, p=0,08, P=0,43, effet de taille (r)=0,21) En conclusion, il semble qu'un test progressif de deux minutes par palier permet de déterminer la progression de la VO2RM et pourrait servir d'évaluation respiratoire dans le cadre d'un programme de réadaptation. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : muscles respiratoires, VO2, blessés médullaires, test progressif

Vinyasa yoga, also known as power flow yoga, is growing in popularity in western cultures. Vinyasa yoga is characterized by moving with the breath and connecting the postures by a series of dynamic movement in between traditional yoga poses. The purpose of this thesis was to determine the intensity and metabolic costs of a typical Vinyasa yoga routine by measuring respiratory gas exchange, heart rate, and perceived rating of exertion. Secondary purposes were to determine whether there were differences between beginner and advanced practitioners and between males and females. Eight beginner (4 males and 4 females) and eight advanced (4 males and 4 females) yoga practitioners were tested while completing a Vinyasa yoga routine. Participants first completed a maximal aerobic test on a treadmill to determine maximal aerobic capacity, and to allow the assessment of relative workload during a subsequent yoga session. After adequate rest, the participant completed a 90-minute familiarization of the Vinyasa yoga session at his or her own skill level. After 4 – 7 days the participants returned, where the beginners completed the beginner routine and the advanced practitioners were randomly assigned to do either the beginner or advanced routine. The advanced practitioners came back on a separate day to complete the routine they had not yet completed. To allow participants to move freely, a portable system (Cosmed K4b2) was used to measure respiratory gas exchange (i.e. oxygen consumption and carbon dioxide output). A heart rate monitor was worn to collect heart rate data. Rating of perceived exertion was measured at set times throughout the session. The mean metabolic equivalents (METs) of Vinyasa yoga (4.7) were significantly higher (p < 0.001) than the 3.0 METs needed to achieve a moderate intensity based on the Canadian Physical Activity Guidelines. During the yoga session, 68 ± 10 minutes were spent above 3.0 METs (moderate intensity) and of those minutes, 16 ± 16 were spent above 6.0 METs (vigorous intensity). Based on the Canadian Guidelines for Physical Activity of 150 minutes per week of moderate intensity activity, three 90-minute Vinyasa yoga sessions a week can meet the recommendations for adults.

Orientador: Benedito Sérgio Denadai / Banca: Camila Coelho Greco / Banca: Marco Tulio de Mello / Resumo: O surgimento de equipamentos que permitem a análise do consumo de oxigênio (VO2) respiração-a- respiração, tem despertado um grande interesse nos fatores que podem influenciar sua cinética no início do exercício (resposta on). Entre os fatores mais estudados, temos a intensidade do exercício e o nível do treinamento dos sujeitos. Estes dados sugerem que a influência do exercício prévio sobre o VO2 durante o exercício incremental só ocorreria em baixas intensidades de esforço (< 60% VO2max). Os objetivos deste estudo foram: a) analisar a influência do exercício supramáximo realizado previamente, sobre os parâmetros da cinética do VO2 durante a transição repouso-exercício realizado a 50 e 70% VO2max, e b) analisar a influência do exercício supramáximo realizado previamente sobre as respostas cardiorrespiratórias e metabólicas durante o exercício de carga constante realizado a 50 e 70% VO2max. Para este estudo foram utilizados 14 ciclistas bem treinados do sexo masculino (VO2max = 63,4 + 6,5 ml.kg-1.min-1; idade = 21,4 + 3,5 anos; massa corporal = 68,1 + 6,8 kg; estatura = 174,9 + 4,6 cm) que executaram cinco testes: 1) exercício contínuo progressivo até a exaustão voluntária para a determinação do VO2max e as cargas correspondentes a 50, 70 e 120% VO2max e; 2) Quatro testes de carga constante, executados de forma aleatória e em dias separados. Nestes testes os sujeitos pedalaram durante 20 minutos em duas diferentes intensidades de exercício (50 e 70% do VO2max), realizados com e sem a execução prévia de um exercício supramáximo (120% VO2max). Foi analisada a resposta on do VO2 e também as respostas cardiorrespiratórias e metabólicas durante 20 minutos de exercício com carga constante realizados a 50 e 70% VO2max... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The appearance of an equipment that permits the oxygen consumption analysis (VO2) breath by breath has arisen a huge interest in factors which can influence its dynamics in the beginning of exercise (on response). Among the more studied factors, are the exercise intensity and training status. Meanwhile, few studies have analyzed the possible effects of previous exercise on the VO2response during exercise at moderate domain. In our lab, we have verified recently that during an incremental test performed eight minutes after a supramaximum exercise (120% VO2max), there was a significant VO2 increase in the first stage, while, at the intensities between 60% and VO2max, no alteration of VO2 was found, in accordance with the results existent in the literature. These results suggest that the influence of a previous exercise on the VO2 during the incremental exercise would just occur at low intensities (< 60% VO2 max). This model, meanwhile, does not permit to isolate a possible time effect of the exercise, once the highest intensities were always done after two or three stages, which could have favored a recovery, at least partially, of the metabolic conditions. In this way, the data until the present moment do not permit to identify if the normalization of VO2 during the incremental exercise is more dependent on the time and/or the exercise intensity. Therefore, the aims of this study were: a) to analyze the influence of the previous supramaximum exercise on the VO2 kinetics during the rest-exercise transition carried out at 50 and 70% VO2max, and b) to analyze the influence of the previous supramaximum exercise on the cardiorespiratory and metabolic responses during the constant loading exercise performed at 50 and 70% VO2max... (Complete abstract, click eletronic address below) / Mestre

Submitted by Heitor Rapela Medeiros (heitor.rapela@ufpe.br) on 2015-03-05T17:52:00Z No. of bitstreams: 2 DISSERTAÇÃO MAÍRA FLORENTINO PESSOA.pdf: 1523827 bytes, checksum: 7ffc0da85f9b2c8361ba8bbb5407bffe (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-05T17:52:00Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO MAÍRA FLORENTINO PESSOA.pdf: 1523827 bytes, checksum: 7ffc0da85f9b2c8361ba8bbb5407bffe (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012-04-10 / A vibração surgiu como forma de treinamento em 1970 e evoluiu para a vibração de corpo inteiro ou Whole Body vibration (WBV), que é aplicada como treinamento e de forma terapêutica, sendo bastante utilizada nos idosos. Por ser um treinamento global, seus efeitos reportam-se a diversos sistemas, tendo efeitos comprovados no ganho de força, na densidade mineral óssea e no equilíbrio de idosos. Entretanto, seus efeitos sobre o sistema cardioplumonar ainda não foram bem documentados. Desta forma, o objetivo deste estudo foi avaliar os efeitos do treinamento em plataforma vibratória comparado com o exercício resistido no sistema cardiopulmonar de idosos, num ensaio clínico controlado randomizado e triplo-cego. Finalizaram o estudo 25 idosos com média de idade de 68,5±3,2 anos, sendo 11 indivíduos do sexo masculino e 14 do sexo feminino. Os idosos foram randomicamente alocados em três grupos: Resistidos, Plataforma e Plataforma+resistidos, que treinaram duas vezes na semana por 03 meses consecutivos. O grupo Resistidos realizou treinamento de musculação com sham para plataforma, o grupo plataforma realizou treinamento com o aparelho MY3® e sham para resistência e o grupo Plataforma+resistidos realizou as duas intervenções. Os sujeitos foram submetidos à avaliação nos momentos inicial e final, através da ergoespirometria, pletismografia optoeletrônica (POE), força respiratória e qualidade de vida. Os resultados do pós-treino foram avaliados na sua normalidade e homogeneidade e comparados ao controle de exercícios resistidos através do teste one-way ANOVA através do SPSS 15.0. Os resultados apresentaram ganhos significativos nos dois grupos que utilizaram a plataforma para as variáveis: VO2, VCO2, VE/VCO2 na ergoespirometria; capacidade inspiratória na POE com redistribuição dos volumes pulmonares para a caixa torácica pulmonar a abdominal; PImáx e PEmáx através da manovacuometria e capacidade funcional, aspectos físicos, dor, estado geral da saúde e vitalidade através da avaliação da qualidade de vida com o questionário SF 36. Conclui-se que a plataforma é um exercício que melhora a capacidade funcional, a capacidade inspiratória, a força respiratória e a qualidade de vida de idosos de ambos os sexos.

Le modèle bioénergétique de P.E. di PRAMPERO permet d'expliquer la performance dans les disciplines de locomotion (course à pied, cyclisme, natation, ...) à partir d'une puissance métabolique et d'un indice de la dépense d'énergie par unité de distance parcourue. Néanmoins, pour les épreuves de natation de haute intensité telles que le 100m crawl, le contexte environnemental rend l'estimation de la puissance métabolique d'origine aérobie techniquement difficile. L'objectif de cette thèse est alors de proposer une nouvelle approche des réponses aérobies d'un 100-m nage libre, réalisé dans des conditions les plus proches possible d'une compétition. Le travail expérimental a porté sur des nageurs entraînés. Dans un bassin de 25-m, la procédure propose que les nageurs réalisent une performance sur 100-m nage libre à allure de compétition et trois épreuves (25m, 50m, 75m) réitérant les mêmes allures intermédiaires que celles du 100-m. VO2 est mesuré avant et juste après chaque épreuve, pendant 1min, par rétro-extrapolation. Les valeurs de VO2 mesurées à la fin des épreuves de 25m, 50m, 75m et 100m permettent de reconstruire la cinétique de VO2 d'une épreuve de 100-m. Les résultats contrastent avec les estimations des cinétiques de VO2 publiées précédemment : VO2 augmente plus vite dans la première moitié de l'épreuve (à 50m, VO2 ≈ 94%VO2max), atteint 100 %VO2max au 75ème mètre de l'épreuve puis chute de 7% sur le dernier 25-m. Une estimation de la contribution relative du métabolisme aérobie montre également des valeurs plus importantes que celles publiées jusqu'à ce jour, du fait de l'atteinte précoce de VO2max en cours d'épreuve. / The bioenergetic model proposed by P.E. di PRAMPERO explains performance in most human locomotions (running, cycling, swimming, ...) using indexes of metabolic power and energy cost of locomotion. Nevertheless, for 100-m front crawl events, environmental conditions make the aerobic power measurement difficult. The main purpose of this thesis is therefore to propose a new procedure to estimate aerobic responses during a 100-m front crawl event, performed in competition conditions. Trained swimmers participated to this study. In a 25-m swimming pool, the procedure includes a 100-m front crawl performance in competition conditions, and then, three tests (25-m, 50-m, 75-m) following the pacing strategy of the 100-m event. VO2 is not measured during the tests, but before and just at the end of each test with a breath-by-breath method. Each post-test VO2 (after 25m, 50m, 75m and 100m) allows to reconstruct the VO2 kinetics of the 100-m performance. The results differ from previous studies in that VO2 increases faster in the first half of the race (at 50m, VO2 ± 94%VO2max), reaches VO2max at the 75th meter; then a decrease in VO2 corresponding to 7% of VO2max appears during the last 25m. The estimation of aerobic contribution shows higher values than those previously published, because VO2max is reached very early during the race.

L'objectif de ce travail était d'étudier l'oxygénation globale et musculaire au cours de l'exercice intense tout en vérifiant les hypothèses explicatives de l'excès (Δ) de VO2 et la composante lente (CL) de VO2 observés respectivement au cours de l'exercice incrémental et à charge constante. La première étude a renforcé le lien entre ΔVO2 et le travail respiratoire. La deuxième étude a montré les importantes sollicitations des muscles respiratoires au cours de l'exercice à charge constante corrélées avec CL VO2 comparées à l'exercice incrémental. De plus, cette étude a permis à travers de l'enregistrement de l'oxygénation au niveau du vaste externe de confirmer l'existence CL VO2 et l'absence ΔVO2 local. Malgré les origines communes entre CL VO2 et ΔVO2, ces deux phénomènes ne sont pas de corrélés. La corrélation entre l'oxygénation globale et locale au cours de l'exercice à charge constante nous a conduits à la troisième étude s'intéressant à investiguer cette relation en fonction de l'intensité de l'exercice. En effet, cette corrélation a été impactée par l'intensité avec une composante lente locale qui n'était pas différente entre les deux intensités. Associé à ceci, le taux total d'hémoglobine a diminué à l'exercice sévère avec des sollicitations ventilatoires plus importantes comparées à l'exercice intense. Dans ce sens, la dernière étude révèle que l'endurance des muscles respiratoire est corrélée à la baisse de saturation tissulaire en oxygène au niveau du vaste externe à la fin de l'exercice ainsi qu'à la performance.Ces résultats contribuent à la compréhension de l'oxygénation globale et musculaire et en particulier ΔVO2 et CL VO2 et leurs origines / The aim of this work was to study whole-body and muscle oxygenation during heavy exercise with checking of underpinning mechanisms of excess (Δ) VO2 and VO2 slow component (SC) observed during incremental and constant-load exercises, respectively.The first study has endorsed the link between ΔVO2 and respiratory work. The second study highlighted the higher solicitation of respiratory muscles during the constant-load exercise correlated to the VO2 SC compared to incremental exercise. Additionally, this study confirms by means of recorded vastus lateralis oxygenation responses the existence of VO2 SC and the lack of ΔVO2. Even mechanistic basis induced VO2 SC and ΔVO2 are the same, a lack of correlation was observed between these phenomena. The significant correlation observed between whole-body and local oxygenation during the constant-load exercise has led us to investigate the effect of exercise intensity on this relationship in the third study. The local VO2 SC did not differ between two exercises intensities and its relationship with the whole-body VO2 SC was impacted. Furthermore, the total hemoglobin and ventilatory work have decreased and increased, respectively during severe compared to heavy exercise. In this context, the last study shows that respiratory muscles endurance is correlated to the decrease of vastus lateralis tissue oxygen saturation at the end of exercise and performance. These results contribute to the understanding of global and muscle oxygenation and especially ΔVO2, VO2 SC and their underpinning mechanisms