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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.
381

Estudo da eficácia da drenagem linfática manual na mobilização hidroeletrolítica, na taxa lipolítica e na variabilidade da frequência cardíaca em homens e mulheres / Study of effectiveness of manual lymphatic drainage in the hydroelectrolytic mobilization, in the lipolytic rate and heart rate variability in men and women

Camargo, Érica Aparecida Mariano, 1989- 03 June 2015 (has links)
Orientadores: Maria Cristina Cintra Gomes Marcondes, Dora Maria Grassi Kassisse / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T12:12:43Z (GMT). No. of bitstreams: 1 Camargo_EricaAparecidaMariano_M.pdf: 3544834 bytes, checksum: d9515fe1a07bef154d0bed7c21be4a79 (MD5) Previous issue date: 2015 / Resumo: A importância da validação científica de técnicas coadjuvantes a diversos tratamentos de saúde é inquestionável. Assim a influência da drenagem linfática manual na mobilização hidroeletrolítica, na taxa lipolítica, bem como, no sistema nervoso autonômico ainda precisa ser investigada. O objetivo deste trabalho foi avaliar o efeito da drenagem linfática manual na mobilização hidroeletrolítica, na taxa lipolítica e na modulação autonômica da frequência cardíaca em homens e mulheres. Foram estudados 11 homens; 11 mulheres não usuárias de anticoncepcional oral e 12 mulheres usuárias de anticoncepcional oral, com 21,3 ± 2,9 anos de idade, saudáveis, sedentários e eutróficos. As amostras urinárias foram coletadas em um dia, sem intervenção terapêutica, denominado controle e em outro dia com aplicação da drenagem linfática manual. Na urina, foram analisadas osmolaridade, concentração de sódio, fluxo e concentração de glicerol. A variabilidade da frequência cardíaca foi registrada no início, durante e ao final do experimento, nos dias controle e drenagem linfática manual. Os resultados mostram que a drenagem linfática manual promoveu em homens redução dos eletrólitos urinários e aumento do fluxo e em mulheres não usuárias de anticoncepcional oral houve apenas aumento do fluxo. A técnica induziu diluição urinária em homens e mulheres não usuárias de anticoncepcional, sugerindo que os mecanismos são sexo-dependentes. Para usuárias de anticoncepcional oral, a drenagem linfática manual não diferiu do dia controle, onde houve redução dos eletrólitos e aumento do fluxo urinário. A análise da concentração de glicerol urinário mostrou que a drenagem linfática manual não altera a taxa lipolítica nos voluntários dos grupos estudados. Os resultados da modulação autonômica da frequência cardíaca indicaram que a técnica promoveu predomínio simpático no grupo de homens sem alterações nos grupos das mulheres. Conclui-se que a drenagem linfática manual foi eficaz na diluição urinária de homens e mulheres não usuárias de anticoncepcional oral, assim como, foi eficaz em promover predomínio simpático em homens. A técnica não foi eficaz em promover alterações na taxa lipolítica / Abstract: The importance of scientific validation techniques supporting the various health treatments is unquestionable. Thus, the influence of manual lymphatic drainage in the electrolyte mobilization in lipolytic rate as well as in the autonomic nervous system has to be investigated. The objective of this study was to evaluate the effect of manual lymphatic drainage in the electrolyte mobilization in lipolytic rate and autonomic modulation of heart rate in men and women. 11 male patients; 11 women not using oral contraceptives and 12 women used oral contraceptives, with 21.3 ± 2.9 years old, healthy, sedentary and eutrophic. The urine samples were collected in one day, without therapeutic intervention, denominated as the control and on another day with application of manual lymphatic drainage. In the urine, were analyzed osmolality, sodium concentration, flow, and the concentration of glycerol. The heart rate variability was registered at the outset, during and at the end of the experiment, in the days control and manual lymphatic drainage. The results showed that the manual lymph drainage in men promoted reduction of urinary electrolytes and increased flow and in women non-users oral contraceptives there was only increased flow. The technique induced urinary dilution in men and women non-users oral contraceptives, suggesting that the mechanisms are sex-dependent. For oral contraceptive users, manual lymphatic drainage did not differ from control day where there was a reduction of electrolytes and increased urine flow. The analysis of urinary glycerol concentration showed that manual lymphatic drainage does not change the lipolytic rate in voluntary groups studied. The results of the autonomic modulation of heart rate indicated that the technique promoted sympathetic predominance in men group and without changes in women. We conclude that manual lymphatic drainage was effective in urinary dilution of men and women non-users oral contraceptives, as well as, it was effective in promoting sympathetic predominance in men. The technique was not effective in promoting changes in lipolytic rate / Mestrado / Fisiologia / Mestra em Biologia Funcional e Molecular
382

An Automatic Biodiesel Decanting System for the Optimization of Glycerin Separation Time by Applying Electric Field and Temperature

Bulnes, Kevin, Paredes, Diego, Vinces, Leonardo 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / During biodiesel production, crude biodiesel and glycerin are separated in resting tanks due to gravity and differences in density, glycerin accumulates at the base of the contender; such operation is called decantation. The decantation stage, within the production of biodiesel based on recycled oil, takes from 8 to 24 h to complete. Therefore, the development of an automatic biodiesel decanting system is presented in order to optimize the production time in the line of this bio-fuel. The process consists of applying an electric field through two electrodes at 9 kV and simultaneously applying temperature. The results of the implementation showed that the production time was reduced by up to 99% without affecting the quality of biodiesel, according to the parameters of the American Society for Testing and Materials (ASTM). / Revisión por pares
383

Dielektrická relaxační spektroskopie glycerolu / Dielectric Relaxation Spectroscopy of Glycerol

Stráník, Rostislav January 2008 (has links)
This doctoral thesis deals with the analysis of dielectric spectra of glycerol with dielectric relaxation spectroscopy (DRS). Dielectric spectra of glycerol have been measured in the frequency range 20 Hz to 10 MHz and in the temperature range 10 K to 300 K. The observed dielectric spectra featured a typical relaxation maximum, which could be in the first approximation described by the Arrhenius equation. The activation energy of the relaxation process observed was 90 MJ/kmol. The relaxation strength as well as the shape of the relaxation peak remained in the temperature interval 180 K - 230 K (visibility of peak) almost the same, thus indicating that no change of the relaxation mechanism comes about. Much attention was in the thesis paid to the analysis of the excess component of the relaxation alfa process, in the literature commonly denoted as "excess wing". The thesis puts forward a procedure for the quantification of the magnitude of the excess wing. The excess wing magnitude thus determined turns out to increase monotonously with increasing temperature. The excess wing is here interpreted as a manifestation of a weakly-pronounced beta relaxation.
384

Valorisation du glycérol sous irradiation micro-ondes : synthèse de quinoléines, de l’échelle du laboratoire à l’échelle pilote / Glycerol valorization under microwave irradiation : quinolines synthesis, from laboratory to pilot scale

Saggadi, Hanen 09 July 2014 (has links)
Le glycérol, principal coproduit de l’industrie du biodiesel (10% massique), représente un solvant et un réactif d’un grand intérêt pour la chimie verte. La déshydratation du glycérol en acroléine est une voie intéressante pour sa valorisation. En effet, cet aldéhyde constitue une molécule plate-forme pour de nombreuses applications. En revanche, il s’agit d’un produit instable, toxique et inflammable, ce qui rend sa manipulation et sa manutention particulièrement dangereuses. Cette difficulté peut être surmontée par une transformation in-situ de l’acroléine formée par déshydratation du glycérol, telle que la réaction de Skraup pour la synthèse de la quinoléine à partir du glycérol et de l’aniline. Le noyau quinoléique se trouve dans des alcaloïdes de plantes médicinales et constitue un composant structurel essentiel de nombreux produits pharmaceutiques. Vu l’intérêt de ces molécules, la réaction de Skraup pour la synthèse des quinoléines s’avère un choix intéressant. Cependant, cette réaction a souvent lieu dans des conditions dures, notamment en utilisant l’acide sulfurique comme solvant, en présence d’un agent oxydant souvent toxique, à hautes températures (T>150°C) pendant plusieurs heures.D’autre part, le chauffage par micro-ondes représente une technologie intéressante capable d’offrir un chauffage volumique efficace du milieu réactionnel, et de réduire les dépenses énergétiques du processus dues aux pertes thermiques et au temps de réaction relativement long. Cette technologie alternative, couplée à l’axe de valorisation du glycérol, représente une voie intéressante de développement pour la chimie verte, et pour l’intensification de procédés plus surs et durables. Dans ce contexte, Le travail présenté dans ce mémoire s’intéresse à la synthèse de quinoléines via la réaction de Skraup en utilisant une technologie alternative de chauffage : les micro-ondes. Une procédure expérimentale plus «verte» est mise au point. A l’échelle du laboratoire, un processus expérimental de synthèse des quinoléines via la réaction de Skraup a été mis au point. A partir de cette étude, l’intensification du procédé à l’échelle pilote a été réalisée. Un réacteur micro-ondes fonctionnant en batch et en continu a été conçu et installé. Le pilote développé permet d’étudier la réaction de Skraup dans les conditions de température et de pression nécessaires. / Glycerol, the main byproduct of the biodiesel industry (10% w/w), is a solvent and a reagent of great interest for green chemistry. Glycerol dehydration to acrolein is an interesting way for its valorization. Indeed, this aldehyde is a platform molecule for many applications. However, it is an unstable, flammable and toxic product, which makes its handling and storage particularly dangerous. This difficulty can be overcome by in-situ conversion of acrolein resulting from glycerol dehydration, such as Skraup reaction for quinoline synthesis starting from glycerol and aniline. Quinoline moiety is found in alkaloids medicinal plants and is an essential structural component of many pharmaceuticals. Since the importance of these molecules, Skraup reaction for the synthesis of quinolines is an interesting choice. However, this reaction requires often harsh conditions, by using sulfuric acid as solvent, in the presence of a toxic oxidizing agent, at high temperatures (T > 150 °C) for several hours.Moreover, microwave irradiation is an interesting technology for chemistry since it can heat homogeneously and quickly a reaction mixture, which can reduce process energy costs resulting from thermal losses and relatively long reaction time. This alternative technology, coupled with glycerol valorization axis, is an interesting development way for green chemistry, and for intensification of safer sustainable processes. In this context, this thesis focuses on the quinolines synthesis via Skraup reaction using an alternative heating technology: microwaves. A greener experimental procedure was developed. At laboratory scale, a greener experimental procedure for quinolines synthesis via Skraup reaction was proposed. On the basis of this investigation, the intensification of a microwave pilot scale apparatus was studied. A microwave reactor operating in batch and continuous conditions was designed and installed. The developed device allowed us to perform the Skraup reaction in the required temperature and pressure conditions.
385

Híbridos ureasil-poliéter conjugados com zeólitas MFI para acetilação do glicerol /

Pereira, Elen Maria Feliciano. January 2019 (has links)
Orientador: Celso Valentim Santilli / Banca: Leila Aparecida Chiavacci Favorin / Banca: Eduardo Ferreira Molina / Resumo: Neste trabalho a metodologia sol-gel foi utilizada para a preparação de materiais híbridos orgânico-inorgânicos (HOI) à base de óxido de poli-etileno (PEO), ligado de forma covalente com o agente acoplador 3(isocianatopropil) - trietoxisilano (IsoTREOS) conjugados com um material zeolítico do tipo MFI, visando aplicações como catalisador para a reação de acetilação do glicerol e assim agregar valor a esse coproduto gerado na produção do biodiesel. O objetivo desta dissertação é demonstrar que o sinergismo entre híbridos do tipo siloxano-poliéter e as zeólitas pode ser explorado na produção de hidrogéis com atividade catalítica. As análises por Microscopia Eletrônica de Varredura (MEV) evidenciaram a homogeneidade na dispersão do material zeolítico na matriz híbrida Os difratogramas de raios-X apresentaram os picos característicos da estrutura cristalina da zeolita ZSM-5 após a conjugação com a matriz U-PEO. Os resultados de Calorimetria Diferencial de Varredura (DSC) revelaram que não ocorre uma mudança significativa na temperatura de transição vítrea (Tg), após a conjugação da matriz híbrida com a zeólita e revelaram uma diminuição do pico endotérmico associado à fusão dos domínios cristalinos do PEO1900, indicando uma possível interação matriz-zeólita. As análises por Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) confirmaram a interação entre a matriz híbrida e a zeólita pelo deslocamento das bandas associadas ao oxigênio tipo éter não coordenado. Medid... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work the sol-gel methodology was used for the preparation of organic-inorganic hybrid (HOI) materials based on polyethylene oxide (PEO) - covalently bonded with the coupling agent 3 (isocyanatopropyl) triethoxysilane (IsoTREOS) conjugate with a zeolitic material of the MFI type, aiming at applications as catalyst for glycerol acetylation reaction and thus add value to this byproduct generated in biodiesel production. The objective of this dissertation is to demonstrate that the synergism between siloxane-polyether hybrids and zeolites can be explored in the production of catalytic activity hydrogels. Scanning Electron Microscopy (SEM) analyzes showed homogeneity in the dispersion of zeolite material in the hybrid matrix. XDR patterns showed the characteristic peaks of the ZSM-5 zeolite crystal structure after conjugation with the U-PEO matrix. Differential Scanning Calorimetry (DSC) results revealed that no significant change in glass transition temperature (Tg) occurs after conjugation of hybrid matrix with zeolite and revealed a decrease in endothermic peak associated with fusion of crystalline domains of PEO1900., indicating a possible matrix-zeolite interaction. Fourier Transform Infrared Spectroscopy (FTIR) analyzes confirmed the interaction between the hybrid matrix and zeolite by shifting the bands associated with uncoordinated ether oxygen. Small-angle X-ray Scattering (SAXS) measurements showed that the starting reagents in the solketal production reaction w... (Complete abstract click electronic access below) / Mestre
386

Biodegradation and ageing of bio-based thermosetting resins from lactic acid

Gomes Hastenreiter, Lara Lopes January 2019 (has links)
The need for replacing petroleum-based polymers has been increasing and bio-based polymers prove to be a suitable solution. The aim of this thesis was to synthesize bio-based resins with different chemical architectures to evaluate the effect of the structure on the properties and on their response to ageing and biodegradation. For this, three different bio-based thermoset resins have been synthesised by reacting one of three distinct core-molecules with lactic acid. The options of core-molecules chosen for this work were ethylene glycol, glycerol and pentaerythritol. Lactic acid was first reacted with a core-molecule by direct condensation, the resulting branched molecule was then end-functionalized with methacrylic anhydride. The amount of moles of lactic acid varied according to which core-molecule it was reacted with, but the chain length (n) was always maintained as three. Part of the samples were characterised by Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and tensile test. DSC and TGA were used for determining the thermal behaviour. FT-IR was used to verify the first and second stage of the reaction and to ascertain the occurrence of the crosslinking reaction. Tensile test was done for investigation of mechanical properties. The ageing and biodegradation tests are useful to ascertain the material possible applications. Therefore, the samples that went through the process of ageing or biodegradation were also characterised in the end of the procedures to further check the effect of those processes on the specimens. The test results indicated that the PENTA/LA cured resin was the most stable thermally. The cured resin’s mechanical properties were similar to each other, so there was no comparison to make in this area. The samples proved to be affected by the biodegradation and the ageing processes, both in visual and structural aspects.
387

Modulation of Factors Guiding Neotissue Formation for Improvement in Tissue Engineered Vascular Grafts and Wound Healing

Zbinden, Jacob C. January 2021 (has links)
No description available.
388

The Development Of Bio-Composite Films From Orange Waste : A Methodological And Evaluation Study Of Material Properties

Syed, Samira January 2021 (has links)
Bioplastic research has become more diverse and different types of research on bioplastic production have been conducted from fruits and vegetable waste, for example, orange waste. The wastes that come from oranges contain more than just vitamins, it has soluble sugars, starch, hemicellulose, cellulose, and pectin. The intention of this project was to study the possibility to produce bio-composite films from orange waste, after removing the soluble sugars. It was also to analyze the properties of the material by tensile strength, visual observation, and to find a methodology that suits this study. An ultrafine grinder was used to mechanically separate the cellulose fibres, with the intention to compare the fibrillation cycles on the properties of the bio-composite films. A total of 30fibrillation cycle was performed. In addition, different film casting strategies were performed and evaluated. The primary plan was to produce a biofilm without the use of chemicals. After the observing the results three new routes for the methodology was developed where the usage of chemicals was be included. The citric acid was used as a solvent for pectin and glycerol was used as a plasticizer. In the first method, different concentration of citric acid and glycerol were added and observed. The combination which gave uniformed films that contained 0.3 g of citric and 0.375 g of glycerol for a 75 ml hydrogel. The second method was to infuse citric acid before grinding the orange waste suspension. Lastly, the third method was to bleach the orange waste before grinding. The films that were produced gave interesting results and from the tensile testing implied that an impact was made on the strength by every fibrillation. The amount of glycerol was consistent throughout the project, but by adding different amount of citric acid gave the films differentIIproperties. The same happened when changing the mould of the film. The best values of the films were from the 30th fibrillation, gave the mean value of 31.6 MPa in tensile strength, and had a strain in elongation at 6.1 %. The tensile strength and elongation had increased drastically compared the fifth fibrillation which had 9.8 MPa and 7.6%.
389

Studies on 1-acyl-sn-glycerol-3-phosphate acyltransferase of Shewanella livingstonensis Ac10 / Shewanella livingstonensis Ac10の1-アシル-sn-グリセロール-3-リン酸アシルトランスフェラーゼに関する研究

Cho, Hyun-Nam 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18346号 / 農博第2071号 / 新制||農||1024(附属図書館) / 学位論文||H26||N4853(農学部図書室) / 31204 / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 栗原 達夫, 教授 植田 充美, 教授 小川 順 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
390

COUPLED DYNAMICS OF HEAT TRANSFER AND FLUID FLOW IN SHEAR RHEOMETRY

Sridharan, Harini 26 August 2020 (has links)
No description available.

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