In this study the action of high hydrostatic pressure (HHP) on compression heating of liquid foods and pressure transmitting fluids, inactivation of Escherichia coli and Listeria innocua in different food media (milk and fruit juices), pulsed pressure and high pressure carbon dioxide treatments was investigated. The experimental results in this study allowed pointing out some important results: (i) The thermal effects of compression should be taken into account when HHP pasteurization processes are developed. Initial temperature of the food product and compression rate should carefully be selected in order to compensate the compression heating / (ii) The HHP inactivation kinetics need not follow traditional first-order kinetics, hence alternative inactivation models are ought to be found. Weibull model can be used for HHP inactivation kinetics of microorganisms / (iii) The pulsed pressure treatment could be an alternative to continuous HHP, but optimization should be done between the pulse holding time, the number of pulses and the pressure level to reach the desirable number of log-reduction of microorganisms (E. coli and L. innocua) compatible with an industrial application / (iv) The storage duration and storage temperature after HHP treatment should carefully be optimized to increase the safety of HHP treated fruit juices since the growth of injured microorganisms can be avoided during storage / (v) The high pressure carbon dioxide (HPCD) treatment in combination with pulsed pressure can be an efficient way to inactivate the microorganisms in skim milk and to reduce the maximum pressure level for the desired log-reduction.

High interstitial fluid pressure (IFP) in tumours is recognized as a barrier to drug delivery resulting in reduced efficacy. High IFP impedes the normal process of convective fluid flow (CFF) from blood vessels into the interstitium. The aim of this study was to develop an in vitro model that could be used to measure CFF and to study its effects on drug delivery. The model consists of a transwell cell culture insert which supports the growth of multicell layers (MCL) on collagen coated membranes. A graduated tube is inserted into the transwell and a pressure gradient is applied across the membrane by raising the volume of medium in the tube above that of the bottom chamber. CFF is determined by measuring the weight of medium in the bottom chamber as a function of time. CFF was inversely proportional to MCL thickness and 41.1±3.6µm thick MCL has completely stopped CFF. Using a physiologically relevant hydrostatic pressure of 28mmHg, a CFF of 21µL/min was recorded using a DLD-1 MCL that was 12.21±3.2µm thick. Under these conditions, the rates of penetration of doxorubicin, imatinib and gefitinib were respectively 42, 26 and 13 folds greater than when no CFF exists. Reversing the CFF so that it opposed the drug diffusion gradient significantly impairs drug penetration. In conclusion, a novel in vitro model for assessing the impact of CFF on drug delivery has been developed. This model could be used to evaluate strategies designed to increase drug delivery to solid tumours by modifying the CFF.

Hypertension and salt-sensitivity are independent risk factors for cardiovascular disease. Although both conditions are idiopathic, they develop due to a complex interplay between susceptibility genes and environmental factors. Given that the kidney plays an important role in regulating blood pressure, in particular, by maintaining sodium and water balance via pressure-natriuresis, it is not surprising that disturbances in the proper functioning of this intrarenal mechanism have been linked to these conditions. Although direct coupling of changes in renal arterial pressure (RAP) to renal interstitial hydrostatic pressure (RIHP) and consequent sodium excretion is well established, few studies have characterized the moment-to-moment aspects of this process. Thus, the main focus of the research presented herein was to characterize the moment-to-moment RAP-RIHP relationship, and assess the functioning of this intrarenal mechanism in various animal models of genetic and environmentally-induced hypertension and/or salt-sensitivity. In adult normotensive rats, the response time of RIHP to acute changes in RAP was rapid (<2 seconds), and the moment-to-moment RAP-RIHP relationship was linear over a wide range of pressures. Additionally, the functioning of this relationship was not affected by inhibition of the renin-angiotensin system and autonomic nervous system. Further, the acute RAP-RIHP relationship was impaired in hypertension and/or salt-sensitivity. Specifically, animals with a hypertensive phenotype (i.e. young spontaneously hypertensive rats [SHR] and pro-atrial natriuretic peptide gene-disrupted mice [ANP -/-]) displayed a rightward shift in the moment-to-moment pressure-natriuresis curve towards higher RAP. This rightward shift was associated with increased structurally-based vascular resistance properties in the hindlimb of young SHR versus their normotensive controls. Salt-sensitive phenotypes were associated with a blunting of this acute mechanism. Specifically, this blunting was evident in both the ANP -/-, a transgenic model of salt-sensitive hypertension, and in adult perinatal iron deficient (PID) rats, a developmentally programmed model of salt-sensitivity. It appears that a blunting in the RAP-RIHP relationship is influenced by an imbalance of key blood pressure modulating factors (e.g. ANP). Further, visceral obesity was associated with salt-sensitivity in PID rats; however the mechanism(s) are yet to be elucidated. Novel methodologies (MRI, abdominal girth) were developed for non-invasive assessment of visceral obesity to aid future research. / Thesis (Ph.D, Pharmacology & Toxicology) -- Queen's University, 2010-05-12 10:11:21.197

The topic of this thesis is called "Technical Landmarks in the Třeboňsko Region and their Application in First Grade Primary School Education." The theoretical part focuses on project teaching and the competencies of the first grade primary school pupil in the area of technical education according to the FEP for basic education, chapter "Humans and Their World (Člověk a jeho svět)". Furthermore, this thesis deals with technical landmarks in the Třeboňsko region. The practical part contains several technical landmarks which may be used as inspiration when creating educational projects for structural and technical education. Some of these projects have been applied in teaching in a small-class primary school. The final part of the thesis contains questionnaires given to first grade primary school teachers to test the indicative functionality of these projects.

Made available in DSpace on 2014-06-11T19:28:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-26Bitstream added on 2014-06-13T20:08:54Z : No. of bitstreams: 1 martinsfilho_pc_me_bauru_prot.pdf: 4223424 bytes, checksum: bd55a8655c281a39d67ddb8401906d98 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se analisar estruturalmente um fermentador de 32 [m] de altura com colunas metálicas de sustentação, submetido ao carregamento de vento estático segundo o procedimento descrito pela norma NBR 6123 (1988), pressão hidrostática e pressão interna dos gases. Duas situações distintas foram consideradas para um melhor entendimento da análise: a primeira, sendo o fermentador vazio submetido aos esforços de vento; a segunda, o fermentador em operação submetido ao carregamento hidrostático e a pressão interna dos gases. Para se obter as tensões nos itens que compõem o fermentador (teto, costado, viga de transição, colunas e fundo cônico) e reações nas bases, foi utilizado o Método dos Elementos Finitos ou MEF. Para isso, foi elaborado um modelo geométrico bem próximo ao real, com os detalhes de chapas internas e externas. Determinou-se a espessura das chapas do costado pela norma NBR 7821 (1983) e verificou-se tensões, e possíveis pontos de falha já ocorridos no setor sucroalcooleiro. Apresenta-se também três problemas analisados pelo MEF que confrontados com os resultados analíticos, permitiu a constatação da validade dos resultados obtidos numericamente o ganho de confiança no uso da ferramenta. O MEF é uma ferramenta auxiliar em casos em que não é possível a utilização de cálculos tradidionais (analíticos) / The objective was to structurally analyze a 32 meter height Fermenter, with columns, submitted to static wind load according to the procedure described by the NBR 6123 (1988) norm, hydrostatic pressure and internal pressure of the gases. Two different situations have been considered for a better analyze comprehension: the first one with the empty Fermenter submitted to wind efforts; the second with the operating fermenter submitted to the hydrostatic load and the internal pressure of the gases. In order to obtain the stresses on the items that make up the fermenter (heads, shell, beam transition, columns and conic bottom) and bases reactions the Finite Element Method or FEM has been used. For this we have developed a geometric model very close to reality, with the details of internal and external plates. It was determined by the thickness of the side shell plating by the NBR 7821 (1983) and there were tensions, and possible points of failure that have already occurred in the alcohol sector. It was also presented three issues addressed by comparing FEM with analytical results, which allowed the verification of the validity of the results obtained numerically and gain of confidence in using the tool. The MEF is an auxiliary tool in cases where it is not possible to use traditional calculations (analytical)

Orientadores: Helena Maria Andre Bolini, Rosires Deliza / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T19:13:21Z (GMT). No. of bitstreams: 1 Marcellini_AlineMotadeBarros_M.pdf: 1250175 bytes, checksum: dbebba72665ad354430068a9e091ff20 (MD5) Previous issue date: 2006 / Resumo: O abacaxi é uma fruta apreciada em todo mundo, devido às suas distintas características sensoriais, podendo ser consumido ¿in natura¿ ou processado de diversas maneiras, sendo o suco a forma de processamento mais popular. O Brasil é o quarto maior produtor mundial de abacaxi, e nos cinco últimos anos a exportação do suco da fruta aumentou cerca de sete vezes. Associado à produção deste está o tratamento térmico, que afeta a qualidade sensorial, produzindo alterações desagradáveis ao produto. Nos últimos anos, os consumidores têm procurado por alimentos que mantenham as características sensoriais e nutricionais do produto, aliado à garantia da segurança microbiológica. A Alta Pressão Hidrostática (APH) é uma tecnologia inovadora, capaz de inativar microorganismos patogênicos e deteriorantes, enquanto minimiza a perda da qualidade sensorial e nutricional do alimento. Este trabalho teve como objetivo processar suco de abacaxi (Ananás comosus (L.) Merril, variedade Smooth Cayenne) através da tecnologia de APH aplicada à polpa do fruto e avaliar as características microbiológicas, sensoriais e a aceitabilidade do produto obtido. Os dados foram analisados através da Análise de Variância (ANOVA), testes de médias de Tukey, Análise de Componentes Principais (ACP), Mapa Interno da Preferência, ¿Cluster Analysis¿, bem como Mapa Externo da Preferência utilizando o programa estatístico SAS e XLSAT. O processamento a APH da polpa de abacaxi por 300MPa e 5 min à 25oC, demonstrou ser eficaz para a produção de polpa com vida útil de 14 dias, estando de acordo com os parâmetros determinados pela legislação brasileira. Os resultados obtidos na determinação de concentração de polpa e doçura ¿ideais¿ para a formulação do suco de abacaxi foram 56,5% e 7,0%, respectivamente. A Análise Descritiva Quantitativa demostrou a similaridade sensorial entre as amostras de suco de abacaxi obtida através da polpa ¿in natura¿ e da polpa tratada por APH (300MPa/5 min/25oC) e que de forma geral, possuem diferença significativa (p<0,05) das amostras comerciais estudadas. Os atributos sabor de suco de abacaxi natural, cor característica de suco de abacaxi natural, aroma característico de suco de abacaxi natural, consistência e presença de fibras visual e percebida na boca apresentaram maior importância para a caracterização dos produtos obtidos através da polpa ¿in natura¿ e da polpa tratada por APH (300MPa /5 min/ 25oC). O teste de aceitação comprovou que as amostras de suco de abacaxi obtidas através da polpa ¿in natura¿ e da polpa tratada por APH (300MPa/5 min/25oC), apresentaram aceitação significativamente (p<0,05) superior às amostras comerciais avaliadas, e sem diferença (p<0,05) entre si, sendo preferidas por segmentos específicos de consumidores. Os atributos que apresentaram maior importância na caracterização dos produtos obtidos através da polpa ¿in natura¿ e da polpa tratada por APH (300MPa/5 min/25oC) dirigiram a preferência de alguns segmentos de consumidores / Abstract: Pineapple is a well appreciated fruit worldwide due to its distinct sensory characteristics, to be consumed ¿in natura¿ or processed in many different ways, juice being the most popular industrialized product. Brazil is the fourth world pineapple producer, presenting a seven fold increase in pineapple juice exportation in the last five years. Thermal treatment associated to juice production affects its sensory quality, resulting in unacceptable changes in the industrialized product. Nowadays consumers are searching for Technologies which preserve nutritional and sensory characteristics of food, as well as guarantee its microbiological safety. High Hydrostatic Pressure (HHP) is an innovative technology capable of inactivating pathogenic and deteriorative microorganisms while minimizing loss of sensory and nutritional product quality. The objectives of this study were to process pineapple juice (Ananas comosus (L.) Merril, Smooth Cayenne variety) through HHP technology applied to the fruit puree and to investigate the microbiological and sensory characteristics of the obtained juice, as well as its acceptability. Data were analyzed through Analysis of Variance (ANOVA); Tukey¿s mean tests; Principal Components Analysis (PCA); Internal Preference Mapping; Cluster Analysis, as well as External Preference Mapping, using statistical programs as SAS and XLSTAT. HHP processing of pineapple puree at 300 MPa for 5 minutes at 25ºC resulted in the production of pineapple puree with a shelf-life of 14 days, in accordance to microbiological parameters established by Brazilian Legislation. Results found in the determination of ideal pineapple puree concentration and ideal sweetness for pineapple juice formulation were 56.5% and 7.0%, respectively. Quantitative Descriptive Analysis (QDA) revealed a sensory similarity between the pineapple juice samples obtained from the utilization of ¿in natura¿ puree and of HHP treated puree (300MPa/5min/25ºC), both showing a statistically significant difference (p<0,05) compared to the commercial pineapple juice samples evaluated in this study. The following sensory attributes: natural pineapple juice flavor; characteristic natural pineapple juice color; characteristic natural pineapple juice aroma; consistency and visual and mouth-perceived fiber presence were considered the most important concerning the sensory characterization of both juices obtained from the utilization of ¿in natura¿ puree and of HHP treated puree (300MPa/5min/25ºC). The acceptance test established that the pineapple samples obtained from the utilization of ¿in natura¿ puree and of HHP treated puree (300MPa/5min/25ºC) showed higher statistically significant acceptance (p<0,05) in relation to the evaluated commercial samples, bearing no statistical significant difference (p<0,05) between them; each one being preferred by specific consumer segments. The sensory attributes which mostly contributed to the characterization of pineapple juices obtained from the utilization of ¿in natura¿ puree and of HHP treated puree (300MPa/5min/25ºC) drove the preference in some consumer segments / Mestrado / Consumo e Qualidade de Alimentos / Mestre em Alimentos e Nutrição

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Neste trabalho, cristais de l-glutamina (C5H10N2O3) foram submetidos à anÃlises atravÃs da tÃcnica de espectroscopia Raman. Inicialmente realizou-se uma identificaÃÃo tentativa de todas as bandas Raman e em uma segunda etapa obteve-se os espectros do material variando os parÃmetros termodinÃmicos de pressÃo hidrostÃtica e temperatura. A regiÃo espectral para os experimentos realizados em funÃÃo da pressÃo hidrostÃtica esteve entre 40 cm-1 e 3550 cm-1 e a variaÃÃo da pressÃo entre 0 GPa e 5,8 GPa. Os resultados mostram que o cristal de l-glutamina sofre uma transiÃÃo de fase estrutural reversÃvel em torno de aproximadamente 3,0 GPa. As medidas em funÃÃo da temperatura foram realizadas em duas polarizaÃÃes distintas na regiÃo espectral entre 30 cm-1 e 3600 cm-1 e no intervalo de temperatura entre 20ÂC e 140ÂC. Os resultados obtidos em funÃÃo da temperatura nÃo apresentam indÃcios de que o cristal de l-glutamina sofra uma tansiÃÃo de fase ou mudanÃas conformacionais em suas molÃculas na cÃlula unitÃria. / In this work, crystals of l-glutamine (C5H10N2O3) were subjected to analysis by Raman spectroscopy. Initially there was a identification attempt of all Raman bands and a second step we obtained the spectra of material ranging from the thermodynamic parameters of hydrostatic pressure and temperature. The spectral region for the experiments as a function of hydrostatic pressure was between 40 cm-1 and 3550 cm-1 and the variation of pressure between 0 GPa and 5.8 GPa. The results show that the crystal of l-glutamine undergoes a transition reversible structural phase around 3.0 GPa. Measures in function of temperature were made at two different biases in the spectral region between 30 cm-1 and 3600 cm-1 and in the temperature range between 20 ÂC and 140 ÂC. The results as a function of temperature does not provide evidence that the crystal of l-glutamine undergoes a transition phase or conformational changes in their molecules in the unit cell.

Os compostos antioxidantes naturais têm sido cada vez mais investigados devido à necessidade das indústrias alimentícias suprirem as exigências dos consumidores em relação à saudabilidade dos produtos. A quercetina é um flavonoide cujos benefícios estão relacionados principalmente à sua ação antioxidante. Entretando, tal molécula apresenta, geralmente, baixa absorção no trato gastrointenstinal, o que pode ser um obstáculo para sua efetiva ação biológica. Por este motivo, uma alternativa para melhorar a sua bioacessibilidade é a encapsulação em sistemas coloidais baseados em matrizes lipídicas, como os lipossomas. Os lipossomas possuem a capacidade de incorporar tanto bioativos hidrofílicos quanto hidrofóbicos em sua estrutura, bem como proporcionar liberação controlada e aumentar a bioacessibilidade dos ingredientes encapsulados. No entanto, há necessidade do desenvolvimento de processos de produção de lipossomas em maior escala, e dentre os processos possíveis a serem empregados com este objetivo encontra-se o método de produção de injeção de etanol. O objetivo principal da presente Tese foi a microencapsulação de quercetina em lipossomas através do método de injeção de etanol. A dispersão de lipossomas encapsulando quercetina escolhida foi liofilizada, com a intenção de aumentar a estabilidade dos lipossomas e enriquecer o amido de milho. O enriquecimento do amido de milho foi realizado por aglomeração, especificamente pelo método de alto cisalhamento, sendo que o pó alimentício aglomerado resultante foi caracterizado fisicamente e teve suas propriedades físicas melhoradas. Foi possível realizar a aplicação do amido de milho enriquecido com quercetina no antepasto de berinjela, sendo que tal incorporação não alterou significativamente as características do produto. Além disso, o antepasto de berinjela foi processado a alta pressão hidrostática e teve sua estabilidade avaliada, sendo que a utilização do processamento não-térmico apresentou vantagens em relação ao método de processamento convencional. / The natural antioxidant compounds have been increasingly investigated due to the need of the food industry to provide healthier products. Quercetin is a flavonoid, whose benefits are linked mainly with its antioxidant activity. However, this bioactive generally has a low absorption rate in the gastrointestinal tract, which it can be an obstacle for its biological action effective. For this reason, an alternative to improve such bioavailability is to encapsulate quercetina in lipid-based matrices, e.g, liposomes. The liposomes have the capacity to encapsulate both hydrophilic and hydrophobic bioactive, as well as to control the release of the encapsulated bioactives, and enhance their bioavailability. However, there is a need to develop liposome production methods in larger scale, and one of the processes feasible to be scaled up is the ethanol injection method. One of the main objectives of this Thesis was to microencapsulate quercetin in liposomes by ethanol injection method. The dispersion of quercetin-loaded liposomes was lyophilized aiming to increase the stability of liposomes and enrich cornstarch. The enrichment of cornstarch was performed by agglomeration, specifically by high shear method, and the agglomerated food powders were characterized and their physical properties was improved. It was possible to incorporate the enriched cornstarch with quercetin in eggplant sauce, and such application did not change the product characteristics. Also, the eggplant sauce was processed by high hydrostatic pressure and had its stability evaluated, indicating the use of nonthermal technology showed advantages if compared to the conventional thermal processing.

Made available in DSpace on 2016-08-18T18:19:27Z (GMT). No. of bitstreams: 1 Edson Nunes Costa Paura.pdf: 4371864 bytes, checksum: eb38ecee742cbbf15a438597d2ab23de (MD5) Previous issue date: 2010-03-10 / In this work the structural and energetic properties of C60@(17,0) carbon peapods bundle were studied under hydrostatic pressure. To study such properties we use ab initio quantum calculations based on the density functional theory in the approach of the generalized gradient approximation. All simulations were performed using the SIESTA code. The results indicate that the bundles in the study present two phase transitions, the first transitions occurring in range 2.0 GPa - 3.0 GPa and the second occurring around 15.0 GPa, in good agreement with the literature. The analysis of electronics properties through energy bands indicates that the ( it Peapods) from P < 3.0 GPa are semiconductor with visible reduction in the energy gap, while above 3.0 GPa the systems become metallic. Also the energy levels of the band are changed according to the hydrostatic pressure is being applied, such as breaking the degeneracy of the levels of valence bands and conduction bands. To each interval of pressure applied we also calculated the relative volume percentual and cohesive energy as a function of pressure. / Neste trabalho foram estudadas as propriedades estruturais, energéticas e eletrônicas de bundles de peapods de carbono C60@(17,0) submetidos à variação de pressão hidrostática. Para estudar tais propriedades, utilizamos cálculos quânticos de primeiros princípios baseados na teoria do funcional da densidade com a aproximação do gradiente generalizado. Todas as simulações foram realizadas com a utilização do código SIESTA. Os resultados encontrados indicam que os bundles em estudo sofrem duas transiçõesde fase, a primeira ocorrendo no intervalo de pressão 2,0 - 3,0 GPa e a segunda ocorrendo entre 15 - 20.0 GPa, em perfeito acordo com a literatura.A análise das propriedades eletrônicas via estrutura de bandas de energia, indica que os peapods para P < 3,0 GPa são semicondutor com visível diminuição do gap de energia, enquanto que acima de 3,0 GPa os sistemas passam a ser metálico. Também os níveis de energia da banda são alterados conforme a pressão hidrostática está sendo aplicada, como por exemplo, a quebra na degenerecencia dos níveis das bandas de valência e condução. Para cada intervalo de pressão aplicada calculamos o percentual do volume relativo e a energia coesiva do sistema.

Made available in DSpace on 2016-08-18T18:19:29Z (GMT). No. of bitstreams: 1 Wesdney dos Santos Melo.pdf: 3867399 bytes, checksum: 9eb817cf696dfb625968d6de8e41101c (MD5) Previous issue date: 2011-04-18 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / In this work we studied the structural and electronics properties (10; 0)@(17; 0) of double wall BN nanotubes bundle without intercalation and intercalated with the H2SO4 molecule, submitted to variations of hydrostatic pressure. For to study such properties we used the ab initio method employing density functional theory in the approach of the generalized gradient approximation for the exchange and correlation terms. All the simulations were performed using the SIESTA code. In the analysis of all results we observed that the traverse circular section of the nanotubos suffers a structural modification when the applied pressure around 1 GPa both system. Another structural change observed, both systems, appears around 10 GPa. The analysis the electronic properties was accomplished through the bands structure, where it was observed that the two systems considered are semiconductors, but with reduction in the energy gap. The analysis of the population of Mülliken, in the case of the doped system with H2SO4 molecule, shows that the nanotubes transfer charge to H2SO4 molecule, and the transference increases with pressure. / No presente trabalho estudamos as propriedades estruturais e eletrônicas de bundles de nanotubos de BN de dupla camada (10; 0)@(17; 0) sem intercalação e intercalados com a molécula H2SO4, submetidos à variação de pressão hidrostática. Para estudar tais propriedades usamos o método ab initio, baseado na teoria do funcional da densidade e da aproximação do gradiente generalizado para o termo de troca e correlação. Para realizar essas simulações utilizamos o código SIESTA. Realizamos a análise de todos os resultados obtidos e observamos que a seção transversal circular dos nanotubos sofre uma modificação geométrica quando a pressão aplicada é em torno de 1 GPa, tanto no sistema sem dopagem como no sistema dopado. Outra mudança estrutural observada, em ambos os sistemas, ocorre em torno de 10 GPa. A análise das propriedades eletrônicas foi realizada através da estrutura de bandas e foi observado que os dois sistemas considerados permanecem semicondutores, mas com redução no gap de energia. A análise da população de Mülliken no caso do sistema dopado mostra que os nanotubos doam cargas para a molécula H2SO4 e a quantidade de carga doada pelo tubo aumenta conforme a pressão aplicada aumenta.