No description available.

Estudos sobre a dinâmica da água no solo não-saturado passam pela medição, estimativa e/ou previsão do potencial matricial ou do teor de água. Diante disso, o objetivo da presente proposta foi realizar testes e avaliações de três instrumentos com características distintas, capazes de medir o potencial matricial da água no solo seco, sendo eles: um medidor baseado no ponto de orvalho (WP4), um instrumento baseado na pressão (tensiômetro de polímero-PoT) e um instrumento baseado na capacitância elétrica (FDR EC-5). A análise foi realizada em três partes: 1. Avaliação do WP4 com amostras com potencial equilibrado na câmara de Richards ou secas ao ar; 2. Avaliação dos PoT e 3. Experimento comparativo entre instrumentos em colunas de solo. Nesses experimentos foram utilizados materiais de solos com texturas diferentes (um de textura argilosa, um de textura média e um de textura arenosa). Os experimentos foram conduzidos no Laboratório de Física de Solo do CENA/USP em Piracicaba-SP. Os resultados mostram que o FDR EC-5 apresentou bons resultados em relação ao método que foi definido como padrão (método gravimétrico), por mais que possua erros associados à curva de retenção. O WP4, que possui uma ampla faixa de leitura de 0 a -30000 m, não se apresentou muito preciso para solos úmidos (h > -70 m) devido ao seu procedimento de leitura. Para solos muito secos, no entanto, ele se apresenta como uma boa opção. O tensiômetro de polímero mede a pressão diretamente na faixa entre 0 a -150 m. Esse instrumento requer cuidados com o coeficiente de calibração, a verificação do limite individual de funcionamento e o contato entre a cápsula porosa do tensiômetro e o solo / Studies about unsaturated soil water dynamics involve the measurement or prediction of matric potential and/or soil water content. In this study, the objective was to test and evaluate three measurement devices able to measure matric potential in dry soil: a dew point based instrument (WP4), a pressure based instrument (polymer tensiometer - PoT) and an electromagnetic capacitance based instrument (FDR EC-5). The analysis was performed in three steps: 1. Evaluation of WP4 using soil samples in equilibrium with a pressure chamber or with surrounding air; 2. Evaluation of PoT and 3. Experiments to compare devices in soil columns. In these experiments three soil textures were used (clay texture, silt texture and sand texture). The experiments were conducted in the soil physics lab at CENA/Universidade de São Paulo, Piracicaba, Brazil. Results show that the FDR EC-5 performed well when compared to the (standard) gravimetric method, even though it includes errors associated with the retention curve. The WP4 device has a wide reading range of 0 to -30000 m, but is not accurate for saturated or moist soils (h > -70 m) due to its working principle. For very dry soils, however, it is a good option. The polymer tensiometers measure pressure directly and perform in a range between 0 to -150 m. This equipment showed to require special care regarding its calibration coefficient, verification of individual reading limit and the porous cap-soil contact

Estudos sobre a dinâmica da água no solo não-saturado passam pela medição, estimativa e/ou previsão do potencial matricial ou do teor de água. Diante disso, o objetivo da presente proposta foi realizar testes e avaliações de três instrumentos com características distintas, capazes de medir o potencial matricial da água no solo seco, sendo eles: um medidor baseado no ponto de orvalho (WP4), um instrumento baseado na pressão (tensiômetro de polímero-PoT) e um instrumento baseado na capacitância elétrica (FDR EC-5). A análise foi realizada em três partes: 1. Avaliação do WP4 com amostras com potencial equilibrado na câmara de Richards ou secas ao ar; 2. Avaliação dos PoT e 3. Experimento comparativo entre instrumentos em colunas de solo. Nesses experimentos foram utilizados materiais de solos com texturas diferentes (um de textura argilosa, um de textura média e um de textura arenosa). Os experimentos foram conduzidos no Laboratório de Física de Solo do CENA/USP em Piracicaba-SP. Os resultados mostram que o FDR EC-5 apresentou bons resultados em relação ao método que foi definido como padrão (método gravimétrico), por mais que possua erros associados à curva de retenção. O WP4, que possui uma ampla faixa de leitura de 0 a -30000 m, não se apresentou muito preciso para solos úmidos (h > -70 m) devido ao seu procedimento de leitura. Para solos muito secos, no entanto, ele se apresenta como uma boa opção. O tensiômetro de polímero mede a pressão diretamente na faixa entre 0 a -150 m. Esse instrumento requer cuidados com o coeficiente de calibração, a verificação do limite individual de funcionamento e o contato entre a cápsula porosa do tensiômetro e o solo / Studies about unsaturated soil water dynamics involve the measurement or prediction of matric potential and/or soil water content. In this study, the objective was to test and evaluate three measurement devices able to measure matric potential in dry soil: a dew point based instrument (WP4), a pressure based instrument (polymer tensiometer - PoT) and an electromagnetic capacitance based instrument (FDR EC-5). The analysis was performed in three steps: 1. Evaluation of WP4 using soil samples in equilibrium with a pressure chamber or with surrounding air; 2. Evaluation of PoT and 3. Experiments to compare devices in soil columns. In these experiments three soil textures were used (clay texture, silt texture and sand texture). The experiments were conducted in the soil physics lab at CENA/Universidade de São Paulo, Piracicaba, Brazil. Results show that the FDR EC-5 performed well when compared to the (standard) gravimetric method, even though it includes errors associated with the retention curve. The WP4 device has a wide reading range of 0 to -30000 m, but is not accurate for saturated or moist soils (h > -70 m) due to its working principle. For very dry soils, however, it is a good option. The polymer tensiometers measure pressure directly and perform in a range between 0 to -150 m. This equipment showed to require special care regarding its calibration coefficient, verification of individual reading limit and the porous cap-soil contact

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-11T11:12:48Z No. of bitstreams: 1 2015 - Gabriel Alves B. de Mello.pdf: 1441001 bytes, checksum: f14810fd41daf598ec3de18bceee8a01 (MD5) / Made available in DSpace on 2017-04-11T11:12:48Z (GMT). No. of bitstreams: 1 2015 - Gabriel Alves B. de Mello.pdf: 1441001 bytes, checksum: f14810fd41daf598ec3de18bceee8a01 (MD5) Previous issue date: 2015-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The application of different irrigation and fertilizer doses can promote changes in onion crop production variables. The aim of this study was to evaluate the effect of organic fertilizer levels (castor bean) coverage and blades irrigation applied by an automatic starter irrigation (AAI) in organic production of onion (Allium cepa L.). The experiment was conducted in the period June to October 2014 in Fazendinha Agroecol?gica 47 km (Integrated System Agroecological Production - ISAP), located between the coordinates 22?45` S and 43?41`W in the municipality of Serop?dica-RJ. The experimental design was a randomized complete block in a factorial scheme 4 x 3, with 12 treatments and 5 repetitions. The treatments were characterized by applying 4 irrigation levels (L1, L2, L3 and L4) and three doses of organic fertilizer: 300g / m?, 200 g / m? and lack of castor bean. The evaluated production variables were total productivity bulbs (TPB), fresh weight of bulbs (FWB), dry matter content of the bulbs (DMCB), dry matter productivity bulb (DMPB), average diameter bulbs (ADB); the bulbs were divided into seven cross-sectional diameter classes. It was also determined the total soluble solids (TSS) and efficiency of water use (EWU).The data were tabulated and submitted to analysis of variance and means were evaluated with the help of regression and Tukey test for the blade factor irrigation and fertilizer doses. The water depth factor significantly influence the values of TPB, FWB, DMPB and ADB ranging, respectively, 19.42 to 31.95Mg ha-1 of 61.12 to 83.30 g, the 1.73 2.59 t ha-1and the 4.52 to 5.13mm.The DMCB variables, TSS and the EWU were not affected by water depth, which showed values from 7.9 to 8.6%, from 14.6 to 16.7 ? BRIX and 83.1 to 105.5kg ha-1 mm-1.Organic fertilizer applied in coverage factor did not influence in any of the production variables, and this fact, as a result, possibly fertilization used in planting the seedlings and the high fertility of the soil level of the experimental area. We conclude that the organic cultivation of onion is promising in the environmental conditions of the Baixada Fluminense region and automation in micro-irrigation system is able to provide water content suitable soil along the onion crop cycle. The larger productive performances of culture were shown with larger water depths applied voltages / A aplica??o de diferentes l?minas de irriga??o e doses de adubo org?nico podem promover altera??es nas vari?veis de produ??o da cultura da cebola. Objetivou-se neste trabalho avaliar o efeito de doses de aduba??o org?nica (torta de mamona) por cobertura e l?minas de irriga??o aplicada por um acionador autom?tico de irriga??o (AAI) na produ??o org?nica da cebola (Allium cepa L.). O experimento foi conduzido no per?odo de junho a outubro de 2014 na Fazendinha Agroecol?gica km 47 (Sistema Integrado de Produ??o Agroecol?gica - SIPA), localizado entre as coordenadas 22?45` S e 43?41`W, no munic?pio de Serop?dica-RJ. O delineamento experimental adotado foi de blocos completos casualizados, distribu?dos em esquema fatorial 4 x 3, com 12 tratamentos e 5 repeti??es. Os tratamentos foram caracterizados pela aplica??o de quatro l?minas de irriga??o (L1, L2, L3 e L4) e tr?s doses de adubo org?nico: 300 g m-?, 200 g m-? e aus?ncia de torta de mamona. As vari?veis de produ??o avaliadas foram produtividade total de bulbos (PTB), massa m?dia fresca de bulbos (MMFB), teor de mat?ria seca dos bulbos (TMSB), produtividade massa seca de bulbo (PMSB), di?metro m?dio de bulbos (DMB), os bulbos foram separados em sete classes de di?metro transversal. Foi determinado tamb?m o teor de s?lidos sol?veis totais (TSST) e a efici?ncia do uso da ?gua (EUA). Os dados foram tabulados e submetidos ? an?lise de vari?ncia e as m?dias foram avaliadas com aux?lio da t?cnica de regress?o e teste Tukey, para os fatore l?mina de irriga??o e doses de adubo org?nico. O fator l?mina de irriga??o influenciou significativamente os valores da PTB, MMFB, PMSB e DMB que variaram, respectivamente, de 19,42 a 31,95 Mg ha-1, de 61,12 a 83,30 g, de 1,73 a 2,59 Mg ha-1 e de 4,52 a 5,13 mm. As vari?veis TMSB, TSST e EUA n?o foram influenciadas pela l?mina de irriga??o, as quais apresentaram valores de 7,9 a 8,6 %, de 14,6 a 16,7 ?BRIX e de 83,1 a 105,5 kg ha-1 mm-1. O fator adubo org?nico aplicado em cobertura n?o exerceu influ?ncia em nenhuma das vari?veis de produ??o, sendo esse fato, decorrente, possivelmente da aduba??o usada no plantio das mudas e pelo n?vel elevado fertilidade do solo da ?rea experimental. Concluiu-se que o cultivo org?nico da cebola ? promissor nas condi??es edafoclim?ticas da regi?o da Baixada Fluminense, e a automa??o em sistema de microirriga??o ? capaz de propiciar conte?do de ?gua no solo adequado ao longo do ciclo de cultivo da cebola. Os maiores desempenhos produtivos da cultura foram evidenciados com as maiores l?minas de ?gua aplicadas

Les enjeux de santé publique et de développement durable conduisent à intensifier l’utilisation de protéines végétales notamment dans les secteurs de biens de consommation comme l’industrie pharmaceutique,l’agro-alimentaire et les cosmétiques. La levée récente de certains verrous technologique permet aujourd’hui la purification industrielle de protéines végétales issus de tourteaux provenant de la production d’huiles végétales. Ces protéines sont valorisables comme substituts aux graisses saturées dans la structuration d’huiles à destination de la consommation humaine. Le manque de texture d’huiles végétales insaturées peut être compensé par ces protéines jouant le rôle de stabilisants et de gélifiants dans les émulsions. Nous nous intéressons aux propriétés fonctionnelles des protéines de blé, de tournesol et de colza, en volume et aux interfaces. Nous avons montré que des gels de protéines de tournesol avec des élasticités modulables sont obtenus par dénaturation thermique. La dynamique de formation de films protéique aux interfaces fluides a été étudiée en combinant des mesures de tensiométrie, de viscoélasticité dilatationnelle et d’ellipsométrie. Les mesures sur plusieurs ordres de grandeurs en concentrations et en temps mettent en évidence différents régimes de structuration associés à différentes dynamiques d’adsorption pour les trois protéines de blé, de tournesol et de colza étudiées. Nous discutons également le rôle de la flexibilité des protéines dans ces différents régimes de structuration. / Challenges of public health and sustainable development trend to intensify the use of vegetables proteins, particularly in consumer goods sectors such as pharmaceutical, food and cosmetics industries. The recent overcome of technical limitation allows the industrial purification of vegetables proteins derived from meal made by vegetable oils production. These proteins are valuable as substitutes for saturated fats in structuring oils for human consumption. The lack of unsaturated vegetable oil texture can be reduced by these proteins acting as stabilizers and gelling agents in emulsions. We are interested in the functional properties of wheat, sunflower and rapeseed proteins, by volume and at interfaces. We have shown that sunflower protein gels with modulable elasticities are obtained by thermal denaturation. In addition, we studied the dynamics of protein film formation at fluid interfaces by combining measurements of tensiometry, dilatational viscoelasticity and ellipsometry. We highlight different structuring regimes and discuss the role of protein flexibility in this structuring.

This thesis examines the mechanisms of magnetic particle deposition and retention in human airways for magnetically targeted drug delivery. As this is a novel application, fundamental studies were performed to establish the necessary background knowledge for further development. Magnetic particle deposition from an aerosol in simulated airway conditions was studied using numerical and experimental models. The model results showed qualitative agreement; discrepancies were due to particle aggregation, which enhances deposition. Aerosol flow rate had a limited effect; the main factor in effective deposition was the proximity of the particle trajectories to the magnets. This spatial bias shows the importance of particle distribution in the flow as well as magnetic field geometry. These studies demonstrated the feasibility of capturing magnet particles from aerosol in airway conditions. For retention, clearance of particles due to motion of the mucus lining of the airways must be overcome. Particle retention was studied in vitro using various liquids to simulate mucus and identify relevant parameters. An ex vivo animal tissue model was used to demonstrate feasibility. Retention of 3-5 m diameter iron particles was achieved at reduced liquid/mucus viscosities. Larger (~100 m) particles were retained at normal mucus viscosities. The size dependence shows that particle aggregation after deposition is crucial for effective retention. In vitro retention experiments showed aggregate size is correlated with liquid viscosity, i.e. formation of aggregates is limited by forces opposing particle motion along the mucus layer interface. To determine these forces, particle motion on various air-liquid interfaces, chosen to simulate different mucus properties in isolation, was studied. When surfactants are present, as in the mucus layer, particle motion is limited by a velocity-dependent surface tension gradient as well as viscous drag. Pulling particles through the mucus layer into the tissue beneath was also considered as a potential retention strategy. The force required to pull particles through the mucus layer was also studied using various liquids to simulate mucus properties. In addition to the surface tension force holding the particles at the interface, hydrodynamic forces must be overcome to pull particles into or out of a liquid film such as the mucus layer.

No description available.

Předmětem této práce bylo popsat agregační vlastnosti kyseliny hyaluronové (HA) a jejích hydrofobně modifikovaných derivátů. Za tímto účelem byly připraveny vodné roztoky kyseliny a dvou derivátů, lišící se stupněm substituce a druhem anorganické soli jako prostředím. Koncentrační řady čisté kyseliny hyaluronové a jejích derivátů byly studovány dvěma metodami, tensiometricky a spektrometricky. Povrchové vlastnosti roztoků byly měřeny s použitím kroužku Du Noüy. Zkoumáno bylo také solubilizační chování ve vodě a v chloridu sodném pomocí dvou sond: Coomassie brilantní modři a sudanu III. Amfifilní deriváty hyaluronanu mohou skutečně tvořit hydrofobní agregáty v roztoku a adsorbovat se na rozhraní vzduch–voda. Tato vlastnost je důležitá v souvislosti s transportními systémy léčiv, protože právě hydrofobní domény agregátů hyaluronanu mohou být použity jako nosiče hydrofobních léčiv. Byly zjištěny kritické agregační koncentrace roztoků derivátů hyaluronanu (tensiometricky a spektrometricky), které odpovídají právě těm koncentracím, při kterých vznikají hydrofobní domény.

Made available in DSpace on 2014-06-11T19:30:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-13Bitstream added on 2014-06-13T19:19:37Z : No. of bitstreams: 1 alves_fr_dr_sjrp.pdf: 2029517 bytes, checksum: f737742cea44bc8699abdd17def3823d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Estudos de calorimetria diferencial de varredura (DSC) e fluorescência de estado estacionário da sonda Vermelho do Nilo indicam a formação de vesículas de DODAX (X = Cl- ou Br-) em concentrações de surfactantes tão baixas quanto 10 µM. Estas vesículas foram denominadas microvesículas (µV), cuja Tm diminui monotonicamente com a concentração de DODAX até valores de Tm das vesículas tradicionais preparadas em 1.0 mM do surfactante. O efeito do contra-íon (Br- e Cl-) no comportamento termotrópico de fase das vesículas mistas de DODAB-DODAC foi investigado por DSC, condutimetria e espalhamento dinâmico de luz (DLS). Observou-se que a Tm aumenta sigmoidalmente de 45.8 a 48.9 oC com a fração molar de DODAC (xDODAC), com um ponto de inflexão no ponto eqüimolar. A condutividade e o diâmetro hidrodinâmico das vesículas variam muito pouco com xDODAB, indicando que a densidade superficial de carga das vesículas de DODAX é semelhante entre si, e o efeito do contra íon na Tm de DODAX se deve a interações específicas desses contra-íons na interface das vesículas. Medidas de DSC, fluorescência e turbidez de misturas de DODAB-DDAB indicam que as vesículas de DODAB têm maior afinidade por DDAB do que o oposto, resultando na formação de duas populações de vesículas mistas de DDAB-DODAB, com propriedades distintas. Além disso, medidas de fluorescência mostraram que a presença de pequena quantia de DODAB incorporado nas vesículas de DDAB causa um efeito significante na emissão da sonda devido ao aumento do tamanho das vesículas, sugerido por medidas de turbidez. O estudo dos sistemas DODAB/CnTAB/água na concentração total de surfactante igual a 1,0 e 5,0 mM, variando a concentração de CnTAB, e também mantendo a concentração de DODAB fixa em 1,0 mM, revelou uma forte dependência do comprimento da cadeia de hidrocarbonetos... / Differential scanning calorimetry (DSC) and fluorescence of the probe Nile Red studies reveal the formation of DODAX vesicles (X = Br- and Cl-) at surfactant concentrations as low as 10 µM. These vesicles were referred to as microvesicles (mV), whose Tm decreases monotonically with increasing DODAX concentration to the value for the ordinary vesicles at 1 mM. The effect of counterion (Br- and Cl-) on the thermotropic phase behavior of mixed DODAB-DODAC vesicles were investigated by differential scanning calorimetry (DSC), conductimetry and dynamic light scattering (DLS). Tm increases sigmoidally from 45.8 to 48.9 oC with DODAC molar fraction (xDODAC), with an inflection point at the equimolarity. The conductivity and the apparent hydrodynamic diameter vary little with xDODAB, indicating that the surface charge density is similar for DODAX, evidencing that the effect of counterion on Tm is due to the counterion specific interactions. DSC, fluorescence and turbidity measurements indicate a higher affinity of DDAB for DODAB vesicles than the reverse, resulting in two populations of mixed DDAB-DODAB vesicles with different properties. Besides, fluorescence measurements show that the presence of a small amount of DODAB in DDAB vesicles causes a pronounced effect on the Nile Red emission, due to the increase in vesicle size, as suggested from turbidity results. The study of DODAB/CnTAB/água systems at 1.0 and 5.0 total surfactant concentration, and varying CnTAB concentrations with constant 1.0 mM DODAB revealed a strong dependence of the chain length n and relative concentration of the surfactante in the properties of mixed DODAB-CnTAB vesicles. This study allowed analyzing the thermotropic phase behavior containing different amount of DODAB, and the mechanism of vesicle-micelle transition with increasing CnTAB concentration, below and above CMC... (Complete abstract click electronic access below)

Made available in DSpace on 2016-08-15T20:31:11Z (GMT). No. of bitstreams: 1 JoseRGG_DISSERT.pdf: 1559519 bytes, checksum: d95e795ac3354fb18dac771769a8ef30 (MD5) Previous issue date: 2013-11-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Chitosan is a natural biopolymer that has large portfolio of structural applications with potential mechanical modifications to generate new properties, functions and specially applications in the biomedical field. This work evaluates the induced tissue reaction between chitosan and nylon sutures used on the skin and subcutaneously, after the 7th, 14th and 28th post-operative day. It was also observed the ability to remove the suture by degradation after application of the suture removal spray QiGel®. Thirty five rats were distributed in 2 groups, namely G1 (chitosan), with 20 rats, and G2 (nylon), with 15 ratsin 3 periods of observation. The G1 group had 5 extra rats for the removal test with the spray. The following evaluations were performed: clinical, macroscopic, tension force and histology. The results led us to conclude that the chitosan based sutures showed qualities contribute concerning removal with the Suture Removal QiGel® when compared with manual removal. The tension force evaluation showed that nylon is stronger than chitosan; however there was no difference on the sutured skin in the observed periods. The skin histology showed no difference on the quantification of fibroblast and collagen in both groups in the different observation periods / A quitosana é um biopolímero natural que possuidiversasaplicações estruturais que possibilitam modificações mecânicas para gerar novas propriedades, funções e aplicaçõesespecialmente na área biomédica.O presente estudo objetivou avaliar a reação tecidual induzida pelos fios de quitosana e de náilon suturados na pele e implantados no tecido subcutâneo, após o 7º, 14º e 28º dia pós-operatório, e observar a capacidade de remoção do fio pela degradação após aplicação do spray Suture RemovalQiGel®. Foram utilizadas 35 ratas distribuídas em dois grupos sendo G1 (quitosana), com 20 animais, e G2 (náilon), com 15 animais, em três períodos de observação. Os cinco animais a mais do G1 foram utilizados para comparar a retirada dos fios. Foram realizadas avaliações clínica, macroscópica, tensiométrica e histológica. Os resultados mostraram que o spray (Suture RemovalQiGel®) apresentou qualidades que contribuem com a retirada dos fios, quando comparado a retirada manual. Na avaliação tensiométrica dos fios, o náilon foi mais resistente, enquanto que na tensão da pele não houve diferença nos períodos de observação analisados.Na avaliação histológica da pele, não houve diferença na quantificação de fibroblastos e colágeno em ambos os grupos e períodos analisados