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Determinação do gasto energético de pacientes com doença pulmonar obstrutiva crônica : comparação entre dois métodos de avaliaçãoMuttoni, Sandra Maria Pazzini January 2010 (has links)
Introdução: O gasto energético (GE) dos indivíduos pode ser determinado por diversos métodos, dentre os quais estão a calorimetria indireta (CI) e as equações de predição. Objetivo: Comparar o gasto energético de pacientes com doença pulmonar obstrutiva crônica (DPOC) medido através da CI com o estimado pela equação de Harris-Benedict (HB). Métodos: Estudo transversal incluindo 30 indivíduos com diagnóstico médico de DPOC, segundo critérios GOLD, atendidos no Centro de Reabilitação Pulmonar do Pavilhão Pereira Filho e do ambulatório de Pneumologia, ambos do Complexo Hospitalar Santa Casa de Porto Alegre, no período de fevereiro à setembro de 2010. O gasto energético foi mensurado pela CI usando monitor específico, assim como predito pela equação de HB. Os participantes também foram submetidos à avaliação antropométrica, através dos parâmetros de peso, altura, índice de massa corporal (IMC), dobra cutânea tricipital (DCT), circunferência do braço (CB) e circunferência muscular do braço (CMB), além de aplicação da avaliação nutricional subjetiva global (ANSG), bem como verificação do consumo alimentar. Os valores encontrados foram analisados através do teste t de Student, do teste qui-quadrado de McNemar e pelo método de Bland-Altman, e expressos pela média ± desvio-padrão, com nível de significância estatística p 0,05. Resultados: Do total de 30 portadores de DPOC, 70% eram do sexo masculino com idades de 62,5 ± 11,5 anos e IMC médio de 24,2 ± 4,2kg/m². O gasto energético em repouso (GER) medido pela CI foi de 1.568 ± 234,8kcal e o estimado pela equação de HB foi de 1.312 ± 120,5kcal, com diferença estatisticamente significativa entre os dois métodos (p<0,001). Quanto ao gasto energético total (GET), o valor medido pela CI foi de 2.038 ± 305,23kcal e o predito pela equação de HB foi de 2.047 ± 188kcal, sem apresentar diferença estatística significativa (p=0,853) e demonstrando uma concordância de 96,7% entre os dois métodos. Relativo ao diagnóstico nutricional, ao considerarmos apenas o IMC, 3,3% dos participantes apresentavam desnutrição, 63,3% eutrofia, 23,3% sobrepeso e 10% obesidade enquanto que pelo agrupamento de parâmetros (IMC, DCT, CB, CMB e ANSG), 53,3% dos pacientes apresentaram desnutrição, 33,3% eutrofia, 10% sobrepeso e 3,3% obesidade. Conclusão: O GER foi subestimado pela equação de HB, não apresentando boa concordância com o medido pela CI. Quanto ao GET, os resultados foram significativamente semelhantes demonstrando boa concordância entre os dois métodos. Em relação ao estado nutricional, talvez o IMC não seja suficiente para avaliar a real condição de pacientes com DPOC. / Introduction: The energy expenditure (EE) of individuals can be determined by various methods, among which are the indirect calorimetry (IC) and the prediction equations. Objective: To compare the energy expenditure of patients with chronic obstructive pulmonary disease (COPD) measured by the IC estimate by the Harris-Benedict equation (HB). Methods: Cross sectional study including 30 individuals diagnosed with COPD according to GOLD criteria, seen in the Pulmonary Rehabilitation Center of the Pereira Filho and outpatient pulmonology, both of Santa Casa Hospital Complex of Porto Alegre in the period from February to September 2010. Energy expenditure was measured by IC using a specific monitor, as predicted by the HB equation. Participants also underwent anthropometric assessment, through the parameters of weight, height, body mass index (BMI), triceps skinfold thickness (TSF), mid-arm circumference (MAC) and mid-arm muscle circumference (MAMC), and application subjective global nutritional assessment (SGA) and to determine food consumption. The values were analyzed using the Student t test, chi-square, McNemar and the Bland-Altman and expressed as mean + standart deviation, with statistical significance level p 0.05. Results: Of 30 patients with COPD, 70% were male, aged 62.5 ± 11.5 years and average BMI of 24.2 ± 4.2kg/m². The resting energy expenditure (REE) measured by IC was 1568 ± 234.8kcal and estimated by the HB equation was 1312 ± 120.5kcal, with a statistically significant difference between the two methods (p<0.001). As for the total energy expenditure (TEE), the value measured by ICwo methods (p <0.001). As for the total energy expenditure (TEE), the value measured by IC was 2038 ± 305.23kcal and foretold the HB equation was 2047 ± 188kcal, no statistical significant difference (p=0.853) and showed a concordance of 96,7% between the two methods. Concerning the nutritional diagnosis, we consider only the BMI, 3.3% of participants had malnutrition, 63.3% were eutrophic, 23.3% overweight and 10% were obese while the grouping of parameters (BMI, TSF, CB, CMB and SGA), 53.3% of patients suffered from malnutrion, 33.3% were eutrophic, 10% overweight and 3.3% obese. Conclusion: REE was underestimated by the HB equation, not a good agreement with that measured by IC. As for the GET, the results were significantly similar showing good agreement between the two methods. In relation to nutritional status, BMI may not be sufficient to evaluate the actual condition of patients with COPD.
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Aplicação de métodos termo-analíticos e espectroscóspicos na avaliação do comportamento do fármaco isoniazida frente a adjuvantes tecnológicos / Application of thermo-analytical and spectroscopical methods on the evaluation of the behavior of isoniazid and pharmaceutical excipientsVelásquez Armijo, Cristián Jesús January 2003 (has links)
Os métodos termo-analíticos são ferramentas úteis na avaliação da compatibilidade entre fármacos e adjuvantes, com destaque à calorimetria exploratória diferencial. Neste trabalho foram avaliados a compatibilidade e o comportamento térmico entre a isoniazida e adjuvantes tecnológicos primários usualmente empregados em formas farmacêuticas sólidas. A compatibilidade foi examinada por meio da preparação de misturas físicas binárias do tipo fármaco/adjuvante. Foi investigada também a influência da granulação por via úmida e do processo de compactação para as misturas de isoniazida e adjuvantes com função de material de enchimento e carga e deslizante. A isoniazida apresentou um comportamento térmico não encontrado na literatura. Os adjuvantes avaliados foram: ácido esteárico, amido, celulose microcristalina, crospovidona, croscarmelose sódica, dióxido de silício coloidal estearato de magnésio, glicolato de amido sódico, hipromelose, lactose, manitol, polidona e talco. Para as misturas físicas, a maioria dos adjuvantes mostrou-se compatível com o fármaco em questão. Foram verificadas interações com o ácido esteárico, o glicolato de amido sódico, a lactose, o manitol e a povidona. A isoniazida mostrou a formação de uma mistura eutética com o manitol e de interação química com a lactose. A agregação por via úmida e o processo de compactação não mostraram influências adicionais na compatibilidade das misturas avaliadas. Os resultados observados foram confirmados por métodos não-térmicos como difratometria de raios X, espectroscopia de infravermelho e ressonância nuclear magnética. / Thermo-analytical methods, and specially Differential Scanning Calorimetry, are useful support for the evaluation of compatibility between drug substances and pharmaceutical excipients. In this work were studied the compatibility and the thermal behavior of isoniazid and pharmaceutical excipients, commonly used for the formulation of solid dosage forms. Colloidal silicon dioxide, corn starch, crospovidone, hypromellose, lactose, magnesium stearate, mannitol, microcrystalline cellulose, povidone, sodium croscarmellose, sodium starch glycolate, stearic acid and talc were the excipients employed in these experiments. The compatibility was analyzed testing binary physical drug/excipient admixtures. The effect of wet granulation and compression was also investigated, in this case especially between isoniazid, fillers and lubricant. For almost all excipients no incompatibilities with isoniazid were observed. Interactions were detected when the drug substance was added to stearic acid, sodium starch glycolate, lactose, mannitol and povidone. Isoniazid formed a euthetic mixture with mannitol, whereas a possible chemical reaction occurred between isoniazid and lactose. Wet granulation and compaction of the tested admixtures did not affect the results observed above. These observations were confirmed by non-thermal techniques, such as X-Ray diffractometry, infrared spectroscopy and nuclear magnetic resonance.
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Caractérisation de la nature physique du rejet d’un évent en cas d’emballement de réaction : étude du modèle de désengagement / Characterization of the physical nature of emergency relief vent flow in case of runaway reaction : study of the disengagement modelXu, Jie 09 October 2017 (has links)
Dans l’industrie chimique, la majorité des réacteurs est équipée d’un dispositif « évent de sécurité » permettant d’éviter leur éclatement en cas de surpression accidentelle conséquente à un emballement. La nature physique du rejet (gazeux ou diphasique gaz-liquide) influe fortement sur la taille requise de l’évent. L’objectif de notre étude est de connaitre mieux le comportement de l’écoulement (désengagement) en cas d’un emballement de réaction et de prédire la nature du rejet (mono ou diphasique) notamment à l’échelle industrielle.Une étude expérimentale d’une réaction d'estérification fut réalisée dans un réacteur en verre de 0,5 l afin de visualiser la nature de l’écoulement et de mesurer la fraction de vide moyenne (ᾱ) lors de l’emballement de réaction. Une étude paramétrique fut effectuée de façon à identifier, pour le régime d'écoulement et la transition, les paramètres clés : la viscosité et l’agitation. Un calorimètre pseudo-adiabatique (VSP2) fut utilisé pour étudier la thermodynamique de l’emballement d’estérification. Les bilans massique et énergétique ont été utilisés pour calculer la vitesse superficielle de la vapeur (jg,max). En outre, le jg, max fut calculé aussi à partir de différentes corrélations, issues d’études en colonne à bulles. Une comparaison entre les résultats obtenus a montré l’inadéquation de ces corrélations pour un système réactif. Une carte de régime pour un système réactif a été construite pour la première fois (jg,max versus ᾱ, combinée à l'observation du régime d'écoulement dans le réacteur), avec une méthodologie pour la prédiction de la nature du rejet en cas d’emballement. / In chemical industry, most reactors are equipped with an emergency relief vent to prevent bursting in case of accidental overpressure due to a runaway reaction scenario. The physical nature of the vent release (gas phase or gas-liquid) strongly influences the necessary vent size. The objective is to enhance the knowledge on the flow behavior (disengagement) during a runaway reaction and to be able to predict the nature of the vent flow (1 or 2-phase) namely at industrial scale.Experiments of esterification were done in a 0.5 l glass reactor in order to visualize the flow pattern (hydrodynamic) and to measure the average void fraction (ᾱ) during the runaway. A parametric study was carried out to identify the key parameters onto the flow pattern and transition, they were: the viscosity and the stirring. A pseudo-adiabatic calorimeter (VSP2) was used to study the runaway P and T profile and the kinetic of the esterification. The thermodynamic data and the mass & heat balances were used to calculate the superficial vapor velocity (jg,max). Furthermore, this jg,max was also calculated from different correlations, obtained from bubble column research. A comparison showed the incorrectness of using these correlations for a reactive system. A flow pattern map (jg,max versus ᾱ combined with the observation of the flow pattern,) for a reactive system was built up for the first time together with a methodology to predict the vent flow nature.
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L’impact du traitement des données sur les valeurs obtenues lors d’un test progressif maximal chez l’enfantSuppère, Corinne 08 1900 (has links)
No description available.
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Etude des interactions entre polyélectrolytes de charges opposées par électrophorèse capillaire et titration calorimétrique isotherme / Study of interactions between oppositely charged polyelectrolytes by capillary electrophoresis and isothermal titration calorimetryLounis, Feriel Meriem 14 December 2016 (has links)
L’objectif de cette thèse est d’étudier les interactions entre polyélectrolytes (PE) de charges opposées par analyse frontale continue en électrophorèse capillaire (FACCE) et par titration calorimétrique isotherme (ITC), en fonction de la force ionique du milieu et des paramètres physico-chimiques relatifs aux deux partenaires (taux de charge chimique, masse molaire, ramification). Un copolymère statistique d’acrylamide et de 2-acrylamido-2-méthyl-propane sulfonate (PAMAMPS) de taux de charge variant entre 15% et 100% a été synthétisé et caractérisé pour cette étude. En tant que polycation modèle, la poly(L-lysine) a été retenue, sous sa forme linéaire (PLL) ou ramifiée / hyperbranchée (DGL). Des mesures par turbidimétrie ont permis d’étudier la stabilité des complexes de polyélectrolytes (PEC) en fonction de la force ionique du milieu. La détermination de la stœchiométrie des PEC par 1H-RMN a permis d’établir une règle générale pour prédire les stœchiométries de charge des PEC. Les paramètres thermodynamiques d’interactions (constantes et stœchiométries d’interaction, contribution entropique et enthalpique) ont été déterminés, par le tracé systématique des isothermes d’adsorption, en considérant le modèle d’interactions des sites indépendants de même énergie. Une dépendance linéaire entre le logarithme des constantes d’interactions et le logarithme de la force ionique a été observée. Cette dépendance en force ionique confirme le caractère entropique des interactions entre PE de charges opposées. Elle permet aussi de quantifier le nombre de contre-ions relargués lors de la formation du PEC. Cette quantité de contre-ions libérés a pu être comparée à la quantité totale de contre-ions condensés. Cette modélisation permet, en outre, de prédire les constantes d’interaction pour des taux de charge intermédiaires et à différentes forces ioniques. / The aim of this thesis is to study the interactions between oppositely charged polyelectrolytes (PE) by frontal analysis continuous capillary electrophoresis (FACCE) and isothermal titration calorimetry (ITC) as a function of the ionic strength of the medium and the physico-chemical properties related to the two partners (chemical charge density, molar mass, ramification). Statistical copolymers of acrylamide and 2-acrylamido-2-methyl-propane sulfonate (PAMAMPS) with chemical charge densities varying between 15% and 100% were synthesized and characterized for this study. Poly(L-lysine) under their linear (PLL) or ramified/hyperbranched (DGL) forms were used as model polycations. Turbidity measurements allowed the study of the stability of the polyelectrolyte complexes (PEC) as a function of the ionic strength of the medium. PEC charge stoichiometries were measured by 1H-NMR, and a general predictive rule that estimates the PEC charge stoichiometry was enounced. The thermodynamic binding parameters (binding constant, stoichiometry, enthalpic and entropic contributions) were determined, by systematically plotting the isotherms of adsorption, and using the model of independent and identical interacting sites. A linear dependence between the logarithm of the binding constants and the logarithm of the ionic strength was observed. This linear dependence confirmed the entropic character of the interactions between oppositely charged PE and allowed quantifying the number of released counter-ions that were compared to the total number of condensed counter-ions. Furthermore, this modelling allowed predicting the binding constants for intermediate chemical charge densities and at different ionic strengths.
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Method Development for Thermal Stability Analysis by Circular Dichroism : Application to the Abp1p SH3 domain from yeastSjöstrand, Linda January 2018 (has links)
Thermal stability is an important and interesting physical property of proteins. A common method to study it by is circular dichroism (CD) spectroscopy. The aim of this study was to test methods to improve thermal stability analysis by CD spectroscopy. Experiments were performed using the Abp1p SH3 domain from yeast as a model protein. Thermal denaturation was monitored at multiple wavelengths. It was concluded that for data sets of reasonable quality the choice of wavelength does not affect the results. An approach to estimate stability of thermophilic proteins was tested where thermal stability was measured at different concentrations of the denaturant GuHCl. The thermochemical data was used to estimate the stability in absence of GuHCl by extrapolation. The results were compared to those obtained from CD spectroscopy and differential scanning calorimetry. It was found that a stabilizing effect from low concentrations of GuHCl complicated the extrapolation. It is likely that this method is more successful if there is no stabilizing effect. The effect of ΔCp in stability parameter calculations was investigated with an experimentally and theoretically determined ΔCp. This was further investigated with synthetic data sets. The ΔCp used in calculations had no notable effect, as long as there was no cold denaturation. Although ΔCp is not necessary in calculations, it is an interesting parameter itself. ΔCp can be calculated from the thermochemical data used for extrapolation. The results in this study demonstrate robustness in thermal stability analysis by CD spectroscopy and a potential for development.
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Desenvolvimento de marcador óptico para processamento de poliolefinas / Development of optical marker for polyolefin processesMARCHINI, LEONARDO G. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:51Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:39Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Avaliação dos diagramas de fase do sistema LiF-GdF3-LuF3 utilizando termodinâmica computacional / Assessment of the LiF-LuF3-GdF3 phase diagrams using computational thermodynamicsSANTOS, IVANILDO A. dos 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:58Z (GMT). No. of bitstreams: 1
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Aplicação do poli(epsilon-caprolactona) com estrutura estrelada para obtenção de microesferas biorreabsorvíveis / Aplication of star-shaped poly(epsilon-caprolactone) to prepare bioreabsorbable microspheresCUNHA, TATIANA F. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:41:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:07Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Efeito da radiação ionizante nos revestimentos de cateteres de poliuretano com nanopartículas de prata / Effect of ionizing radiation in polyurethane catheters coatings with silver nanoparticlesHEILMAN, SONIA 03 February 2016 (has links)
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No. of bitstreams: 0 / Made available in DSpace on 2016-02-03T12:13:54Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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