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The Phase change materials (PCM) have the ability to absorb and release heat as the temperature changes from high to low temperature and vice versa. The use of phase change materials has increased in the construction sector due to the established environmental requirements and the various application benefits, especially in the thermal comfort of building applications and construction of sustainable infrastructure around the world (Berardi and Gallardo, 2019). Over the past decade, many studies have been conducted on the thermal properties of PCM (phase change material), however, few studies have focused on the study effect of PCM on mechanical and physical properties, although of great importance. In this work, three different microencapsulated types of phase change material (PCM) have been studied, while its effect on the mechanical and hydration properties of the cement paste with regard to constant ratio of water to cement ratio has been taken into account. The PCMs that have been studied are the following: Microencapsulated PCM, which is Nextek 24 D, Nextek 57D (Microtek Laboratories) and Croda Therm ME29P (Croda). In this study, various tests were performed on cementitious paste mixed with different doses of PCM to test the effect that PCM has on the cement hydration (under semi-adiabatic and isothermal conditions), the physical properties (setting time, slump flow, density) and the mechanical properties ( compressive strength). The results of this study indicated that both the melting point of the PCM and its amount have a decisive effect on the properties of the cement paste. Finally, the following conclusions have been drawn: • Additions of different dosage levels of the 24D and Croda PCM types showed that an increase in the dosage resulted in impaired mechanical and physical properties such as compressive strength of the cement paste (mechanical) decreased, and the density and random flow decreased (physical). While Nextek 57D did not show a great effect on cement paste according to density and random flow, which gives reduced negative impact on cement paste workability (physical). According to the mechanical properties, Nextek57D PCM with different levels of levels showed immediate positive effect on cement paste compressive strength compared to reference paste (no addition of PCM), and other cement pastes with other PCM types used in this study. • Mikrotek 57D PCM also gives a positive effect at different dose levels compared to two other types of Nextek 24D and Croda PCM regarding the effect of heat flow, which gives rise to hydration heat during the cement hydration process. However, other types of Nextek 24D and Croda in all quantities showed negligible effect on the heat flow during the cement hydration process.

Water movement in the body is determined by the osmotic forces acting on the cell membrane. Ingestion of a highly-hypertonic glycerol solution resulting in high extracellular osmolality could drive water out of the intracellular space into the vascular space resulting in reduced muscle hydration and increased blood volume. The aim of this thesis was to study the effects of altered body water distribution during exercise. In chapter 3, ingestion of a 400 ml glycerol solution (1 g·kg-1 body mass) increased serum osmolality (309 mosmol·kg-1) which was associated with a 4.0% increase in blood volume due to a 7.2% increase in plasma volume, attributed to a shift of water from the intracellular space, resulting presumably in tissue dehydration. Glycerol ingestion was then used as a means of altering body water distribution in the other studies described in this thesis. Altered body water distribution had no acute effect on force production during quadriceps muscle isometric exercise (chapter 4), or handgrip strength (chapter 5). Regarding chronic effects (chapter 5), two groups of participants exercised handgrip and initiated recovery after ingestion of either a glycerol solution or placebo over a period of 8 weeks. Maximum handgrip strength increased in both groups and there was no statistically significant difference between the two groups. In chapters 6 and 7, the subjects performed a cycling exercise protocol to fatigue. In the glycerol trial, time to fatigue decreased compared with the iso-osmotic trial during an incremental VO2max test (chapter 6) and during cycling against a constant load at 100% VO2max intensity (chapter 7). In the glycerol trial, there was an accelerated increase in blood lactate and an accelerated increase in serum potassium (chapter 7), indicating altered muscle metabolism which may have contributed to the early development of fatigue.

Le travail de thèse a porté essentiellement sur l'effet des conditions de prise en pression et en température dans une gamme (20-60°C/Patm-200 bar) d'un ciment pétrolier (Portland « classe G ») au très jeune âge (jusqu'à un jour) en condition saturée sur (i) la cinétique d'hydratation, (ii) les propriétés hydriques (perméabilité et porosité) et (iii) le développement des propriétés élastiques dynamiques obtenues par propagation d'ultrasons et quasi-statiques. Les propriétés quasi-statiques instantanées et différées ont été obtenues à partir d'essais mécaniques réalisés en compression simple à différents temps/degré d'hydratation.La partie I a permis de montrer que la pression appliquée pendant la prise a un effet négligeable sur la cinétique d'hydratation contrairement à l'effet accélérateur de la température de prise. Un modèle de cinétique d'hydratation tenant compte de l'effet accélérateur de la température a été mis en place afin de déterminer l'évolution des fractions volumiques des différentes phases en présence dans la pâte de ciment au cours de son hydratation. L'évolution de la phase (porosité capillaire + eau) obtenue par le modèle d'évolution des fractions volumiques est en bonne concordance avec l'évolution de la porosité connectée mesuré par porosimétrie dans la deuxième partie de travail de thèse. En partie II, concernant la caractérisation de la perméabilité, les valeurs obtenues ainsi que l'évolution des propriétés élastiques quasi-statiques obtenue expérimentalement ont permis de déterminer le temps de drainage pour chacune des conditions d'hydratation étudiées. Cette information permet de déterminer la nature drainée ou non drainée des essais mécaniques quasi statiques réalisés. En partie III, les essais mécaniques ont permis d'identifier un comportement granulaire faiblement cohésif au niveau du sommet du pic exothermique, puis un comportement solide cohésif avec progression des propriétés mécaniques au cours de l'hydratation à partir de la décroissance du flux thermique. Enfin, deux modèles par homogénéisation multi-échelles ont été proposés, la différence portant sur la schématisation de la pâte de ciment au très jeune âge. Les résultats ont été confrontés avec succès aux propriétés élastiques dynamiques et quasi-statiques drainées et non drainées obtenues expérimentalement / The thesis primarily concerned the effect of the set conditions in pressure and in temperature in a range (20-60°C/Patm-200 bar) of an oilwell cement (Portland cement class G) at very early age(up to one day) in saturated condition on (I) the hydration kinetics, (II) the hydrous properties (permeability and porosity) and (III) the development of the dynamic elastic properties obtained by ultrasonic propagation and quasi-static properties. The "instantaneous" and differed quasi-static properties were obtained by mechanical tests carried out in uniaxial compression with various times/degree of hydration

Inledning: Jodkontrastmedel är ett läkemedel som administreras av röntgensjuksköterskan för att förbättra kontrasten mellan inre organ och vävnader samt skilja mellan normala och patologiska områden. Jodkontrastmedel gavs uppskattningsvis i 80 miljoner doser över hela världen år 2003. Av kontrastmedel kan allvarlig biverkning eller till och med ett livshotandetillstånd uppkomma som kontrastmedelsinducerad nefropati (KMN). N-Acetylcystein (NAC) har flera egenskaper, bland annat antioxidfunktioner och förbättring av njurarnas perfusion som kan vara bidragande egenskaper till att förebygga KMN. Syfte: Denna litteraturöversikt var att sammanställa om N-Acetylcystein (NAC) är ett effektivt hydreringsalternativ för att förebygga kontrastmedelsinducerad nefropati (KMN) Metod: Studien utfördes som en allmänlitteraturöversikt. Tio vetenskapliga artiklar kvalitetsgranskades, analyserades och resultatet presenterades i kategorier. Resultat: Analysen av tio artiklar resulterade i sex kategorier, om NAC har en bra hydrerande effekt mot KMN, högriskpatienternas utveckling av KMN och NAC:s effekt, kontrastmedelsdos, mätvärden kontrollerade med serumkreatinin och cystatin C, biverkningar från oral och intravenös administration av NAC samt studiernas definition på KMN. Slutsats: NAC tillsammans med hydrering har visat sig i vissa studier vara effektivt mot KMN men det är ändå oklart om det är NAC som ger den positiva effekten. NAC tillsammans med hydrering verkar inte ge några negativa effekter för patienten då NAC har få biverkningar och är ett billigt läkemedel, men röntgensjuksköterskan bör ge kontrastmedelsdos enligt uträknad GFR. / Introduction: Iodine contrast media is a drug that is administered by the radiographer to enhance the contrast between the internal organs and tissues and distinguish between normal and pathological areas. Iodine contrast media is given estimated to 80 million dosesworldwide year 2003. By contrast media, a serious side effect or even a life-threatening condition can arise like contrast induced nephropathy (CIN). N-Acetylcysteine (NAC) has acapacity of antioxidant functions and improvement of renal perfusion, which may be properties to help and prevent CIN. Purpose: This literature review was to compile if N-Acetylcysteine (NAC) is an effective hydrations alternative to prevent contrast induced nephropathy (CIN) Method: The study was conducted as a general literature review. Tenquality scientific articles were reviewed, analyzed and the results were presented in categories. Results: The analysis of the ten articles resulted in six categories, the NAC has a good dehydrating effect against KMN, high-risk patients, the development of KMN and NAC:s effect, contrast media, measurements controlled by serum creatinine and cystatin C, side effects from oral and intravenous administration of NAC and studies definition of KMN Conclusions: NAC with hydration has been shown in some studies to be effective against KMN but it is still unclear whether it is NAC that gives the positive effect. We believe that NAC along with hydration do not hurt to give to the patient when the NAC has few side effects and is an inexpensive drug, but radiographer should give contrast media according to calculated GFR.

Emulsões são sistemas dispersos constituídos de pelo menos duas fases líquidas imiscíveis e um agente emulsificante para estabilização das mesmas. a fase dispersa destesw sistemas é conhecida como fase interna e o meio dispersante como fase externa, porém, são sistemas termodinamicamente instáveis. A presença de cirstais líquidos aumenta a estabilidade destas dispersões e além de alterar a viscosidade. São capazes de promover o encapsulamento de ativos, permitindo liberação sustentada, bem como a proteção dos fármacos foto- e termosensíveis. O óleo de girassol é uma interessante fase oleosa em uma emulsão, pois possui proprie3dades cicatrizantes devido à alta concentração de ácido linoléico e propriedades antioxidantes devido à presença de polifenóis e vitamina E Possuemaplicações em diferentes áreas como: cosméticos, alimentos, veículos de medicamentos e outros. Assim, os objetivos deste estudo foram desenvolver emulsões estáveis contendo cristais líquidos a partir da mistura de óleo de girassol (Helianthus annus L.) e mineral (vaselina líquida), caracterizá-las e avaliar a influência de diferentes ésteres graxos na formação dos cristais líquidos. As formulações foram desenvolvidas utilizando o método de diagrama e pseudo-diagrama ternário, a partir dos quais foram selecionadas duas formulações que demonstraram se estáveis e apresentaram cristais líquidos durante todo o teste de estabilidade acelerada. As mesmas foram aditivadas com extrato glicólico de polifenois e ésteres graxos e permaneceram estáveis com cristal líquido. A caracterização reológica observou-se fluxo pseudo-plástico e tixotrópico, ideal para produtos farmacêuticos e cosméticos. O óleo de girassol apresentou atividade antioxidante mesmo quando aquecidos para o processo de emulsificação pelo método do radical DPPH·. As cadeias carbônicas dos ésteres graxos utilizados em produtos cosméticos podem influenciar na formação e manutenção dos cristais líquidos. Por meio dos testes in vivo observou-se que as formulações desenvolvidas promoveram aumento prolongado da hidratação da pele e não foram observados sinais de irritação cutânea. / Emulsions are dispersed systems consisting of at least two immiscible liquid phases and an emulsifying agent to stabilize them. The dispersed phase of these systems is known as the internal phase and the dispersing environ is the external phase, which are, however, thermodynamically unstable systems. The presence of liquid crystals increases the stability of these dispersions and also change the viscosity. They are able to promote the encapsulation of active, allowing sustained release as well as the protection of photo-and thermo-sensitive drugs. Sunflower oil is an interesting phase in an oily emulsion, because it has healing properties due to the high concentration of linoleic acid, and antioxidant properties due to the presence of polyphenols and vitamin E. They have applications in different areas such as cosmetics, food, medicines and other vehicles. The objectives of this study were to develop stable emulsions containing liquid crystals from a mixture of sunflower oil (Helianthus annus L.) and mineral (mineral oil), characterize them and evaluate the influence of different fatty esters in the formation of liquid crystals. The formulations were developed using the method of diagram and ternary pseudo-diagram, from which we selected two formulations that have been demonstrated stable and presented as liquid crystals throughout the accelerated stability test. They were doped with polyphenols glycolic extracts and acid esters, and have been kept stable with liquid crystal. At the rheological characterization was observed pseudo-plastic flow and thixotropic, ideal for pharmaceuticals and cosmetics. Sunflower oil showed antioxidant activity even when heated to the emulsification process by the radical DPPHo method. The carbon chains of fatty esters used in cosmetics can influence the formation and maintenance of liquid crystals. In vivo tests showed that the formulations developed promoted prolonged increase in skin hydration and were not seen signs of skin irritation.

O progresso científico e tecnológico das últimas décadas registra um avanço significativo no processo de obtenção da cal, porém, há uma lacuna de conhecimento de base referente à sua ação quando empregada em conjunto com o cimento Portland. O uso da cal nas argamassas mistas de acabamento tem sido associado positivamente apenas à plasticidade no estado fresco e à sua deformabilidade no estado endurecido. Maiores informações são necessárias sobre a ação da cal na evolução das propriedades da argamassa no estado fresco, vinculadas à hidratação do cimento. Este conhecimento é importante para o desenvolvimento de formulações que atendam ao desempenho desejado em diferentes aplicações. O entendimento do mecanismo de hidratação do cimento em presença da cal constitui uma plataforma para estudos de adições minerais ativas ao clínquer, com adição de cal hidratada como fonte externa de cálcio, na produção de novos materiais cimentícios sustentáveis. O estudo em pasta realizado teve como foco a interação cimento-cal visando identificar os fenômenos químicos e físicos relevantes que se sucedem à adição de água ao sistema. Foram caracterizadas as idades iniciais de hidratação do cimento por meio de ensaios de calorimetria de condução, termogravimetria (TG/DTG) e difratometria de raios X em material no estado fluido e em regime consecutivo de coleta de dados. Os experimentos envolveram as proporções 1:1 e 1:2 de cimento Portland tipo CP II E com cales hidratadas tipos CH I e CH III de natureza cálcica e dolomítica, respectivamente. A cal CH I incorpora à mistura elevado teor de hidróxido de cálcio com imediata saturação do meio por íons hidroxila e íons cálcio; a cal CH III incorpora também, em maior quantidade, filler carbonático. Por efeito químico, devido à presença da cal, há alteração da velocidade de hidratação, mas com formação dos produtos de reação característicos da hidratação do cimento. Por efeito físico, o filler carbonático e a fração insolúvel do hidróxido de cálcio da cal, presente no meio saturado, atuam como nucleador para precipitação de fases hidratadas. O efeito combinado desses fenômenos promoveu aceleração da hidratação do cimento Portland, principalmente no período de indução, quando prevalecem as reações de formação de etringita e de aluminatos de cálcio hidratados. / In the last decades, scientific and technological progress has shown a significant advance in the process of obtaining lime; however, there is gap knowledge with relation to its action when employed together with Portland cement. The use of lime in finishing mix mortars has only been positively associated to the fresh state plasticity and ability to deformation in the hardened state. It is necessary to collect data about the role of lime in the gradual development of the properties of mortars in the fresh state, linked to cement hydration. Such knowledge is important to develop formulas which can meet the required performance in different uses. The current demand of sustainable materials has favored the addition of minerals to the composition of Portland cement, and hydrated lime as an extern source of calcium, is a feasible alternative to the composition of byproducts and mixtures to be used as alternative binders. This research focused the cement-lime interaction aiming at identifying relevant chemical and physical phenomena which succeed the addition of water to the system. The paste study characterized the early ages of hydration by means of isothermal calorimetric, thermogravimetric, X-ray diffraction in material in the fluid state analysis collecting data in a consecutive basis. The experiments were carried out by using two proportions of Portland cement type CP II E with hydrated lime types CH I and CH III, calcic and dolomitc, respectively. By adding lime CH I to the cement-water system, calcium hydroxide is abundantly incorporated, with immediate saturation by means of hydroxide ions and calcium ions. The addition of lime CH III, also incorporates, in greater amount, finely ground limestone. Due to chemical effect because of the presence of lime, there is alteration in speed of hydration, forming products characteristics to the cement hydration process. Due to physical effect, the filler and the lime insoluble fraction of calcium hydroxide, present in the saturated environment, work as facilitators to the precipitation of the hydrated phases. The combined effect of these two phenomena accelerated hydration of Portland cement, mainly in the induction period, when ettringite and hydrated calcium aluminates formation reactions prevail. The advancement made in terms of knowledge permits to broaden comprehension on the behavior of mixtures in early stages, when hardening and consolidation processes are applied to mortars and help rheologic studies which involve their application. The understanding of the hydration mechanism in the presence of lime sets a base to study additions of active minerals to the clinker and produce new sustainable cementious compounds.

Os cereais matinais são produtos extrusados de alto teor de proteína, carboidratos e fibras, que são consumidos com leite. A modelagem matemática é essencial para predizer e simular o comportamento dos materiais submetidos à hidratação, com o intuito de descobrir as melhores condições de temperatura e de tempo de hidratação do processo. Esse trabalho teve como objetivo modelar e otimizar o processo de hidratação de cereal matinal com leite, visando encontrar as variáveis ideais de tempo e temperatura de hidratação, bem como a proporção de leite e cereal para obtenção de um produto pronto para o consumo, além de utilizar dois modelos matemáticos e rede neural artificial para simular a cinética de absorção de leite. A hidratação foi conduzida em 3 proporções de cereal/leite e 3 temperaturas de imersão durante duas horas, com cereal de milho (sem açúcar) e leite UHT integral. Os tratamentos utilizados na hidratação (proporção, temperatura e tempo) causaram efeito significativo (p < 0.05) em todas as propriedades físico-químicas do cereal matinal hidratado com leite. Dos modelos matemáticos, o modelo de Peleg foi o que melhor descreveu a cinética de absorção de leite no cereal nas temperaturas e proporções investigadas, e obteve bons ajustes aos dados experimentais. A aplicação da rede neural artificial representou de forma satisfatória a cinética de absorção do leite. / Breakfast cereals are extruded products with a high content of protein, carbohydrates and fibers, which are consumed with milk. The mathematical modeling is essential to predict and simulate the behavior of the materials submitted to hydration, in order to discover the best conditions of temperature and hydration time in the process. The objective of this work was to model and optimize the process of breakfast cereal hydration with milk, aiming to find the ideal variables of time and temperature of hydration, as well as the proportion of milk and cereal to obtain a product ready for consumption, besides using two mathematical models and Artificial Neural Network to simulate the kinetics of milk absorption. Hydration was conducted in 3 cereal/milk proportions and 3 immersion temperatures for two hours, with corn cereal (without sugar) and integral UHT milk. The treatments used in hydration (proportion, temperature and time) had a significant effect (p <0.05) on all physical-chemical properties of breakfast cereal hydrated with milk. About mathematical models, the Peleg’s model best described the kinetics of milk absorption in the cereal at the temperatures and proportions investigated, and obtained good adjustments to the experimental data. The application of Artificial Neural Network satisfactorily represented the kinetics of milk absorption.

No processo de beneficiamento da vermiculita é gerado um resíduo fino para o qual atualmente ainda não foi desenvolvida uma aplicação que possibilite a utilização em larga escala. Uma alternativa que vem sendo estudada é a associação com cimento Portland em composições de argamassas e concretos, em função da composição química do resíduo: elevada quantidade de alumínio, silício e magnésio, que podem apresentar interações com o ligante. No entanto, em função da elevada área superficial específica, em comparação ao cimento, sua utilização nas composições pode afetar a demanda de água de amassamento e limitar a sua aplicação. Para tanto, uma alternativa é a calcinação deste resíduo fino, assim como é realizado para outras argilas (caulim, por exemplo), para que a área superficial específica (ASE) seja menor e eventualmente ative propriedades pozolânicas na respectiva argila. Deste modo, neste trabalho foram avaliadas as diversas características de pastas cimentícias após adição de resíduo fino de vermiculita: reação química, formação dos produtos hidratados, propriedades reológicas, tanto após a mistura como ao longo da hidratação. Foi verificado que de forma geral a reação química não é afetada após a adição de vermiculita, embora a formação de aluminatos seja intensificada na composição com maior quantidade de resíduo in natura. Com relação ao seu comportamento no estado fresco, foi observado que a maior ASE do resíduo impacta fortemente as propriedades reológicas das pastas, embora que com um teor de 5% as mudanças sejam menores. Utilizando-se dessas mesmas composições para a avaliação do desempenho no estado endurecido de argamassas, foi verificado que não há efeito sobre essas propriedades até 5% de substituição, independentemente do tratamento térmico empregado. Assim, considerando aspectos econômicos de transporte assim como os custos decorrentes da calcinação, pode-se recomendar a adição de 5% de vermiculita in natura sem comprometer o desempenho dos produtos, embora não se possa precisar com os dados obtidos a sua durabilidade ao longo do uso. / In the process to obtaining vermiculite a fine residue is generated, which does not yet have a large-scale application. An alternative that has been studied is the association with Portland cement in mortar and concrete formulations, as a function of the chemical composition of the residue: high amount of aluminium, silicon and magnesium which may have interactions with the binder. However, the residue has a high specific surface area, in comparison to cement, a fact that can increase the water-demand to mix and limit its application. For this, an alternative is the calcination of this fine residue, as it is done for other clays (kaolin, for example), so that the specific surface area (SSA) is smaller and eventually activates pozzolanic properties in the respective clay. Thus, in this work the various characteristics of cement pastes after addition of vermiculite fine residue were evaluated: chemical reaction, formation of the hydrated products, rheological properties, both after mixing and along the hydration. It was verified that in general the chemical reaction is not affected after the addition of vermiculite, although the formation of aluminates is intensified in the composition with greater amount of in nature residue. Regarding its behaviour in the fresh state, it was observed that the higher SSA of the residue strongly impacts the rheological properties of the pastes, although with a 5% content the changes are minimal. Using these same compositions to evaluate the performance in the hardened state of mortars, it was verified that there is no effect on these properties up to 5% of substitution, regardless of the thermal treatment used. Thus, considering the economic aspects of transport as well as the costs of calcination, it is possible to recommend the addition of 5% of vermiculite in nature without compromising the performance of the products, although it is not possible to determine the its durability during the use.

This thesis aimed to, first, examine the effects of the addition of whey protein or casein protein to common carbohydrate-electrolyte (CE) solutions on post-exercise rehydration; second, examine the effects of various contents of whey protein in CE solutions on post-exercise rehydration; and third, investigate the mechanisms on the increased fluid retention after the ingestion of CE plus whey protein solutions. / The first study (Chapter 4) of this thesis examined the effects of CE solution added with a certain amount of whey or casein protein on post-exercise rehydration. Ten young healthy males (mean ± SEM, age: 20.7 ± 0.4 years; body weight (BW): 65.4 ± 2.0 kg; maximal oxygen uptake (VO₂ₘₐₓ): 60.7 ± 1.9 mL·kg⁻¹·min⁻¹) were recruited in this study. Three main experimental trials were conducted in a randomized single-blinded crossover design and separated by at least 7 days between any two of them. In each main trial, subjects ran for 60 min at 65% VO₂ₘₐₓ on a treadmill in a warm and humid environment (24 °C, 60% relative humidity (RH)), which was followed by a 4-hour recovery period. During recovery, the subjects were provided with either a common CE solution, or a CE with whey protein (CW) solution, or a CE with casein protein (CC) solution. The three solutions were matched for energy and electrolyte content and were provided in six equivalent volumes at 30 min intervals with a total volume equivalent to 150% of their BW loss. The nude BW, urine samples, and capillary blood samples were collected before and after exercise and at the end of each hour during recovery. After exercise, the subjects lost approximately 2.3% of their pre-exercise BW in all trials. Total urine volume after recovery was higher in the CE and CC trials than in the CW trial (CE vs. CW vs. CC: 1184 ± 120 mL vs. 1005 ± 68 mL vs. 1256 ± 130 mL, p < 0.05), which induced greater fluid retention in CW trial compared with both CE and CC trials (CE vs. CW vs. CC: 46.9 ± 5.2% vs. 54.9 ± 2.9% vs. 45.8 ± 5.5%, p < 0.05). By the end of recovery, the urine specific gravity (USG) was lower in the CE trial than in both CW and CC trials (CE vs. CW vs. CC: 1.002 ± 0.001 g·mL⁻¹ vs. 1.004 ± 0.001 g·mL⁻¹ vs. 1.004 ± 0.000 g·mL⁻¹, p < 0.05). In addition, the urine osmolality was lower in the CE trial than in both CW and CC trials after recovery (CE vs. CW vs. CC: 111 ± 18 mmol·kg⁻¹ vs. 181 ± 14 mmol·kg⁻¹ vs. 195 ± 23 mmol·kg⁻¹, p < 0.05). However, no difference was found in the changes of plasma volume among trials throughout recovery. These results suggested that during a 4-hour recovery after 60 min run which induced about 2% BW loss, the CE plus whey protein solution was more effective in fluid retention compared with the isocaloric CE or CE plus casein protein solution. / The second study (Chapter 5) was conducted to examine the effects of various contents of whey protein in CE solutions on post-exercise rehydration; meanwhile, the mechanisms on the greater fluid retention after the ingestion of CE plus whey protein solutions were investigated as well. Ten young healthy males (mean ± SEM, age: 22.0 ± 0.7 years; BW: 64.5 ± 1.9 kg; VO₂ₘₐₓ: 59.8 ± 1.9 mL·kg⁻¹·min⁻¹) finished five main experimental trials in a randomized single-blinded crossover manner and separated by at least 7 days. After a 60-min run at 65% VO₂ₘₐₓ on a treadmill in each main trial, a 4-hour recovery period was carried out. During recovery, five solutions of 1) a CE solution with high CHO content (CE-H); 2) a CE solution with low CHO content (CE-L); 3) a CE solution with high content of whey protein (CW-H); 4) a CE solution with medium content of whey protein (CW-M); and 5) a CE solution with low content of whey protein (CW-L) were consumed by the subjects randomly. The electrolyte content was matched, whereas CE-H, CW-H, CW-M, and CW-L solutions were matched for energy density, CE-L and CW-H solutions were matched for CHO content. The total volume consumed by subjects was 150% of the BW loss, and the solutions were provided in six equal volumes at 30 min intervals during recovery. The nude BW, urine samples, and capillary and venous blood samples were obtained before and after exercise and at the end of each hour during recovery. The results showed that the subjects lost about 2.2% of BW after exercise. By the end of the recovery, the total urine volume was smaller in the CW-M trial than in the CE-H trial (CE-H vs. CW-M: 1295 ± 103 mL vs. 1049 ± 130 mL, p < 0.05), whereas the CW-H trial was smaller than the CE-H, CE-L, and CW-L trials (CE-H vs. CE-L vs. CW-L vs. CW-H: 1295 ± 1033 mL vs. 1284 ± 90 mL vs. 1141 ± 58 mL vs. 891 ± 73 mL, p < 0.01). The less urine production in the CW-M and CW-H trials resulted in a greater fluid retention compared with CE-H, CE-L, and CW-L trials (CE-H vs. CE-L vs. CW-L vs. CW-M vs. CW-H: 38.4 ± 5.2% vs. 36.1 ± 4.3% vs. 43.0 ± 3.8% vs. 51.0 ± 5.7% vs. 55.4 ± 3.8%, p < 0.05). The CE-H and CE-L trials showed lower USG and urine osmolality compared with the CW-L, CW-M, and CW-H trials at the end of recovery (p < 0.05). In addition, the plasma osmolality of the CE-L trial was lower than that of the CW-L, CW-M, and CW-H trials at the 1st hour of recovery (CE-L vs. CW-L vs. CW-M vs. CW-H: 274 ± 4 mmol·kg⁻¹ vs. 291 ± 4 mmol·kg⁻¹ vs. 301 ± 6 mmol·kg⁻¹ vs. 293 ± 6 mmol·kg⁻¹, p < 0.05). The plasma volume was lower in the CE-L trial than that in the CW-H trial at the 2nd and 3rd hour, and the CE-L trial reached the lowest plasma volume than the other four trials by the end of recovery (p < 0.05). The aldosterone concentration was lower in both CE-H and CE-L trials compared with the CW-M and CW-H trials after recovery (CE-H vs. CE-L vs. CW-M vs. CW-H: 228 ± 100 pg·mL⁻¹ vs. 211 ± 51 pg·mL⁻¹ vs. 336 ± 85 pg·mL⁻¹ vs. 333 ± 70 pg·mL⁻¹, p < 0.05). The antidiuretic hormone (ADH) concentration was also found to be lower in the CE-L trial than in the CW-H trial at the 1st and 2nd hour of recovery (p < 0.05). However, no difference was found in plasma albumin concentrations among trials throughout recovery. The results indicated that the CE solutions with higher whey protein content retained more fluid compared with CE solutions with lower whey protein content or CE solution alone. The greater fluid retention was partly caused by the elevated aldosterone concentrations in the situations of current study. / In summary, the experimental results of this thesis found that the consumption of common CE solution plus whey protein can retain more fluid in body than isocaloric CE or CE plus casein protein solution during post-exercise recovery. CE solutions with relative higher whey protein content were more effective in fluid retention than CE solutions with lower whey protein content. Furthermore, the additive effects on fluid retention caused by whey protein supplementation were induced by the increased concentrations of plasma aldosterone. The elevated plasma osmolality and ADH concentrations maybe also played a role in the greater fluid retention. However, further studies are needed to clarify this issue. The current findings provided more evidences in this research topic and suggested some recommendations to athletes and sports enthusiasts to reach rehydration rapidly and effectively after exercise. / 本論文的研究目的包括：首先，研究在普通的碳水化合物-電解質（CE）飲料中添加乳清蛋白或酪蛋白對運動後復水的影響；其次，研究CE飲料中添加不同劑量的乳清蛋白對運動後復水的影響；再次，闡述飲用CE加乳清蛋白飲料後更能有效的將水分保留在人體內的機制。 / 實驗一（第四章）研究了在CE飲料中加入一定劑量的乳清蛋白或酪蛋白對運動後復水的影響。十位年輕、健康男性受試者（平均值 ± 標準誤，年齡: 20.7 ± 0.4 歲；體重: 65.4 ± 2.0 千克；最大攝氧量: 60.7 ± 1.9 mL·kg⁻¹·min⁻¹）自願參加本項測試。按照隨機單肓交叉設計，他們完成了三次主測試，期中任何兩次測試時間都相隔七天以上。在每一次主測試中，受試者首先在跑臺上以65%最大攝氧量的運動強度完成了60分鐘的跑步運動（運動環境控制在24攝氏度，60%相對濕度），隨後開始4小時的運動後恢復階段。在恢復過程中，受試者會分別飲用三種不同飲料中的一種。三種飲料包括：（1）普通CE飲料（CE組）；（2）普通CE飲料中添加乳清蛋白（CW 組）；（3）普通CE飲料中添加酪蛋白（CC 組）。三種飲料含有相同的能量密度及電解質濃度。受試者在每次主測試中飲用的總飲料體積為1.5倍的體重減少量，這些飲料分為6等份并每隔30分鐘由受試者飲用一份。運動前、後及在恢復階段每隔一小時收集受試者的體重（裸重）、尿液樣本、及血液樣本（指尖取血）。在三次主測試中，受試者在運動結束後減少的體重量約為運動前體重的2.3%。在4小時的恢復階段中，CE組和CC組受試者排出的尿液總體積大於CW組（CE vs. CW vs. CC: 1184 ± 120 mL vs. 1005 ± 68 mL vs. 1256 ± 130 mL, p < 0.05）。所以，恢復結束後，CW組的水分保持比例高於CE組及CC組（CE vs. CW vs. CC:46.9 ± 5.2% vs. 54.9 ± 2.9% vs. 45.8 ± 5.5%, p < 0.05）。在恢復結束時，CE組的尿比重低於CW組及CC組（CE vs. CW vs. CC: 1.002 ± 0.001 g·mL⁻¹ vs. 1.004 ± 0.001g·mL⁻¹ vs. 1.004 ± 0.000 g·mL⁻¹, p < 0.05）。另外，在恢復結束後，CE組尿滲透壓水平低於CW組及CC組（CE vs. CW vs. CC: 111 ± 18 mmol·kg⁻¹ vs. 181 ± 14mmol·kg⁻¹ vs. 195 ± 23 mmol·kg⁻¹, p < 0.05）。但是，在恢復階段，血漿容量的變化在三組中沒有顯著差異。本實驗的結果表明，完成60分鐘跑步後，受試者丟失掉約2%的體重，在之後4小時恢復階段中，飲用添加乳清蛋白的CE飲料比有相同能量密度的普通CE飲料或添加酪蛋白的CE飲料更能有效的將水分保留在體內。 / 實驗二（第五章）研究了在普通CE飲料中添加不同劑量的乳清蛋白對運動後復水的影響；同時，也研究了飲用CE加乳清蛋白飲料後更能有效的將水分保留在人體內的機制。十位年輕、健康男性受試者（平均值 ± 標準誤，年齡: 22.0 ± 0.7 歲；體重: 64.5 ± 1.9 千克；最大攝氧量: 59.8 ± 1.9 mL·kg⁻¹·min⁻¹）自願參加本項測試。按照隨機單肓交叉設計，他們完成了五次主測試，任何兩次測試的時間都相隔七天以上。在每一次主測試中，受試者首先在跑臺上以65%最大攝氧量的運動強度完成了60 分鐘的跑步運動，隨後開始4 小時的運動後恢復階段。在恢復過程中，受試者會飲用五種不同飲料中的一種。五種飲料包括：（1）普通CE飲料，含有較高的CHO濃度（CE-H組）；（2）普通CE飲料，含有較低的CHO濃度（CE-L組）；（3）普通CE飲料添加較高劑量的乳清蛋白（CW-H組）；（4）普通CE飲料添加中等劑量的乳清蛋白（CW-M組）；（5）普通CE飲料添加較低劑量的乳清蛋白（CW-L組）。五種飲料含有相同濃度的電解質，其中，CE-H，CW-H，CW-M，及CW-L組有相同的能量密度，CE-L 及CW-H 組有相同的CHO含量。在每次主測試的恢復階段，受試者飲用的飲料總體積為1.5倍的體重減少量，這些飲料分為6等份并每隔30分鐘由受試者飲用一份。運動前、後及在恢復階段每隔一小時收集受試者的體重（裸重）、尿液樣本、及血液樣本（指尖取血及靜脈取血）。運動結束後，受試者的體重減少量約為運動前體重的2.2%，五組測試中沒有顯著差異。在4小時的恢復階段後，CW-M 組受試者的尿液總體積小於CE-H組（CE-H vs. CW-M:1295 ± 103 mL vs. 1049 ± 130 mL, p < 0.05）；同時，CW-H組的尿量低於CE-H，CE-L，及CW-L組（CE-H vs. CE-L vs. CW-L vs. CW-H: 1295 ± 103 mL vs. 1284 ± 90mL vs. 1141 ± 58 mL vs. 891 ± 73 mL, p < 0.01）。相對於CE-H，CE-L，及CW-L組，較少的尿液排出量使CW-M及CW-H組能將更多的水分保留在體內（CE-H vs.CE-L vs. CW-L vs. CW-M vs. CW-H: 38.4 ± 5.2% vs. 36.1 ± 4.3% vs. 43.0 ± 3.8% vs.51.0 ± 5.7% vs. 55.4 ± 3.8%, p < 0.05）。在恢復結束後，CE-H及CE-L組的尿比重水平及尿滲透壓水平低於CW-L，CW-M，及CW-H組（p < 0.05）。另外，在恢復階段的第1小時，CE-L組的血漿滲透壓水平低於CW-L，CW-M，及CW-H組（CE-L vs. CW-L vs. CW-M vs. CW-H: 274 ± 4 mmol·kg⁻¹ vs. 291 ± 4 mmol·kg⁻¹ vs. 301 ± 6 mmol·kg⁻¹ vs. 293 ± 6 mmol·kg⁻¹, p < 0.05）。在恢復階段的第2及3小時，CE-L組的血漿容量低於CW-H組；在恢復結束時，CE-L組的血漿容量低於其它四組（p <0.05）。對于兩種體液平衡調節激素，在恢復結束時，CE-H及CE-L組的醛固酮水平低於CW-M及CW-H組（CE-H vs. CE-L vs. CW-M vs. CW-H: 228 ± 100 pg·mL⁻¹ vs. 211 ± 51 pg·mL⁻¹ vs. 336 ± 85 pg·mL⁻¹ vs. 333 ± 70 pg·mL⁻¹, p < 0.05）。在恢復階段的第1及2小時，CE-L組的抗利尿激素水平低於CW-H組（p < 0.05）。然而，五組測試中，血漿白蛋白水平在恢復階段沒有顯著差異。本實驗的研究結果表明，普通CE飲料中加入較高劑量的乳清蛋白比較低劑量的乳清蛋白更能有效的將水分保留在人體內。這種較高水平的水分保留能力與醛固酮激素水平的升高有關。 / 綜上所述，本論文的研究結果發現，在運動後的恢復階段飲用添加乳清蛋白的CE飲料比有相同能量密度的普通CE飲料或添加酪蛋白的CE飲料更能有效的將水分保留在人體內。並且，在CE飲料中加入較高劑量的乳清蛋白比較低劑量的乳清蛋白對人體內水分的保留更加有效。另外，這種較高水平的水分保留能力是由醛固酮激素水平的升高引起的。同時，較高的血漿滲透壓及抗利尿激素水平可能對這種高效的水分保留能力也有一定的促進作用，但需要更多的研究來闡述這一觀點。本論文的研究結果為運動後復水的相關研究提供了更多的理論證據，並且對運動員及運動愛好者在運動結束後如何進行快速有效的復水提出了指導及建議。 / Li, Liang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 131-149). / Abstracts also in Chinese; appendixes includes Chinese. / Title from PDF title page (viewed on 01, November, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.