781 resultados para poliacrilonitrila modificada
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Introduo: A motilidade esofgica ineficaz (MEI) um distrbio motor que acomete o corpo esofgico, recentemente descrito. Caracteriza-se, manometricamente, pela presena de ondas de baixa amplitude e/ou ondas no transmitidas ao longo do esfago em 30% ou mais das degluties com gua. Nos pacientes com doena do refluxo gastroesofgico (DRGE), a MEI associa-se maior ocorrncia de refluxo na posio supina. Entretanto, o seu impacto na qualidade de vida desconhecido. Questionrios de qualidade de vida, genricos ou especficos, tm sido valiosos instrumentos para mensurar a qualidade de vida pela tica do paciente. Objetivos: 1. mensurar o impacto da MEI nos sintomas da DRGE, confirmada por pHmetria prolongada, medidos por uma escala de qualidade de vida especfica para a DRGE; 2. validar para a lngua portuguesa a escala de qualidade de vida para a doena do refluxo gastroesofgico (EQV-DRGE) de Velanovich; 3. determinar a prevalncia da MEI em pacientes com DRGE confirmada pela pHmetria prolongada. Pacientes e Mtodos: A ausncia de instrumentos para medir a qualidade de vida, especificamente na DRGE, em lngua portuguesa nos levou a traduzir e validar a escala de qualidade de vida de Velanovich em pacientes com DRGE confirmada por pHmetria esofgica prolongada. Nessa escala, obtido um escore especfico para cada sintoma (pirose, regurgitao, disfagia e odinofagia) assim como um escore global entre 0 e 50; quanto menor for o escore melhor ser a qualidade de vida relacionada aos sintomas da DRGE. Aps essa validao, aplicou-se esse instrumento, prospectivamente, em pacientes avaliados no Laboratrio de Fisiologia Digestiva por um perodo de dois anos (agosto/99 e agosto/01). Os pacientes foram submetidos, consecutivamente, anamnese, EQV-DRGE, manometria e pHmetria prolongada. Estudaram-se, nesse grupo de pacientes, a associao entre a presena de MEI e o escore da EQV-DRGE. Resultados: A verso em portugus da escala de qualidade de vida pareceu-nos de fcil compreenso pelos pacientes, estimando-se um acrscimo entre 5 e 10 minutos para o seu preenchimento por paciente. Inicialmente, 219 indivduos foram admitidos ao protocolo. O grupo efetivamente estudado, aps aplicao dos critrios de excluso, consistiu em 124 pacientes com refluxo cido patolgico confirmado, com mdia de idade de 48 anos, predomnio do sexo feminino (65%) e presena de MEI em 40 (32,3%). Os escores das perguntas especficas Voc sente azia quando est deitado?, Voc sente dificuldade para engolir? e o escore global foram significativamente mais elevados no grupo de indivduos com MEI quando comparados com o grupo sem MEI (respectivamente: P=0,019 , P=0,006 e P=0,038). Concluses: 1) a motilidade esofgica ineficaz influencia negativamente a qualidade de vida de pacientes com DRGE medida pela EQV-DRGE, piorando significativamente os sintomas disfagia e pirose em posio supina; 2) a EQV-DRGE traduzida para a lngua portuguesa apresenta evidncias de validade para ser utilizada em pacientes portadores da doena; 3) a motilidade esofgica ineficaz um distrbio motor prevalente na DRGE confirmada pela pHmetria prolongada.
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Bacterial cellulose (BC) has a wide range of potential applications, namely as temporary substitute skin in the treatment of skin wounds, such as burns, ulcers and grafts. Surface properties determine the functional response of cells, an important factor for the successful development of biomaterials. This work evaluates the influence of bacterial cellulose surface treatment by plasma (BCP) on the cellular behavior and its genotoxicity potential. The modified surface was produced by plasma discharge in N2 and O2 atmosphere, and the roughness produced by ion bombardment characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cell adhesion, viability and proliferation on BCP were analysed using crystal violet staining and the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium (MTT) method. Genotoxicity was evaluated using the comet and cytokinesis block micronucleus assay. The results show that the plasma treatment changed surface roughness, producing an ideal cell attachment, evidenced by more elongated cell morphology and improved proliferation. The excellent biocompatibility of BCP was confirmed by genotoxicity tests, which showed no significant DNA damage. The BCP has therefore great potential as a new artificial implant
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This study compared the evolution of posture, tone and neonatal reflexes in preterm infants without clinical or neurological complications before and after the age of term using the scale of Saint-Anne Dargassies. To reach the age of the term, was applied Scales Amiel-Barrier-Shnider changed and the Prechtl, traditionally used in the evaluation of term newborns, looking for possible changes to the term, while also evaluating the sensitivity of these scales. We studied 20 non-complicated preterm infants, both sexes aged 32-36 weeks, born in Janurio Cicco Maternity School, from August 2006 to August 2007. Was applied to the scale of Saint-Anne Dargassies every two weeks until reach the term, and the range of Amiel-Barrier-Shnider changed and the Prechtl, after reaching 39 and 41 weeks. The evaluation result of articular angles was subjected to the test of Friedman ANOVA, significant differences between the three measurements of the scale of Saint-Anne Dargassies only for angles heel-to-ear to term. Neonatal reflexes changed in the period of prematurity were the cardinal points reflexes, Moro reflexes, cross extensions reflex and the automatic walking reflexes. The posture was the parameter which remained unchanged in the three scales. Considering a significance level of 5% by applying Cochran Q Test, it was found that the scale of Saint-Anne Dargassies is more sensitive to detect suspects. With this methodology and the results it was possible to prepare a manuscript: The neurological examination of non-complicated preterm newborns using the Sanit-Anne Dargssies Scale from birth to term: normal or altered? In which we describe that despite the good clinical condition, the RNP show changes in tone and neonatal reflexes. These data are important because though non-complicated RNP need further attention its maturation process, enabling us to detect and intervene early. With these results we can build a scale simplified neurological assessment made with items found most altered during the application of three scales. The development of this project has a multidisciplinary approach, because it involved Paediatric Neurologist, Physiotherapist and Neonatologist, as recommended by PPGCSA
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The aim of this work was to evaluate the quality of yellow melon inodorus Valenciano Amarelo (CAC) fresh cut submitted to two cut types and with application postharvest of calcium chloride. After preparation cubes and slices melon were immersed in solution with different calcium chloride (CaCl2) concentrations for two minutes, afterwards they were conditioned in trays of expanded polystyrene (EPS), covered by plastic film of low density polyethylene (PEBD), stored in cold camera to 5 degrees C +/- 1 and analyzed for 8 days. They were evaluated pH, firmness, tritable acidity (AT), soluble solids (SS) sugar reducer and ratio. The pH values varied from 5.27 to 5.68. The sugars reducers content and the ratio were superior in the slices compared to the cubes. The melon slices maintained larger firmness values compared to the cubes and in general there was reduction in the values of this parameter along the storage period for all treatments. Concentrations of 1.0 and 1.5% of CaCl2, result in larger values of firmness. The storage temperature and modified passive atmosphere they contributed to quality maintenance of MP melon. Concentrations of up to 1.0% of CaCl2 they could be recommended to maintain the melon quality MP melon yellow inodorus (CAC).
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The active modified atmosphere effect was evaluated in the quality of squash fresh-cut (MP).. The squash pieces were conditioned in plastic packings and submitted the gases application in the following concentrations: 0.03% CO2 and 21% O-2 (controls T1); 5% CO2 and 4% O-2 (T2); 6% CO2 and 4% O-2 (T3); 7% CO2 and 4% O-2 (T4); 8% CO2 and 4% O-2 (T5). In T6 it was made vacuum application in the packing. The packings containing the squash were stored in to the temperature of 10 degrees C and relative humidity of 75% for 12 days. The evaluated analyses were weigth loss, total acidity (AT), pH, soluble solids (SS), ratio, firmness, color, antioxidant activity for DPPH and carotenoids content. The weigth loss was gradual and low until the ninth day of storage. The values of AT increased along the experimental period being superior for T1 and T2. The increase of SS during the storage of the fresh-cut squash went smaller for T3 and T4. The brightness stayed during the storage being superior for T5, already the color components red and yellow decreased along the experimental period.
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Objetivou-se, neste trabalho, avaliar o efeito da aplicao de herbicidas em ps-emergncia sobre a eficincia fotoqumica de duas cultivares de soja (M-SOY 7908 RR e M-SOY 8001). O delineamento experimental utilizado foi em blocos ao acaso, com quatro repeties. Os tratamentos constaram da aplicao de herbicidas isolados e em misturas: lactofen, glyphosate, lactofen + chlorimuron-ethyl, chlorimuron-ethyl + imazethapyr, chlorimuron-ethyl + bentazon, glyphosate + imazethapyr, lactofen + chlorimuron-ethyl + imazethapyr e lactofen + chlorimuron-ethyl + imazethapyr/haloxyfop-methyl. Alm disso, foram mantidas duas testemunhas sem aplicao de herbicida. As avaliaes foram realizadas aos 4; 11; 18; 25 e 32 dias aps aplicao dos herbicidas (DAA) no primeiro ano, e aos 6, 14, 21, 28 e 35 DAA, no segundo. A cultivar M-SOY 8001 foi suscetvel aplicao dos herbicidas, principalmente s misturas contendo lactofen + chlorimuron-ethyl e lactofen + chlorimuron-ethyl + imazethapyr + haloxifop-methyl, os quais provocaram reduo no rendimento quntico mximo do PSII (Fv/Fm). As duas cultivares apresentaram suscetibilidade aos herbicidas quando tratados com lactofen aplicado isolado e nas misturas lactofen + chlorimuron-ethyl, chlorimuron-ethyl + imazethapyr, lactofen + chlorimuron-ethyl + imazethapyr e lactofen + chlorimuron-ethyl + imazethapyr + haloxifop-methyl com reduo nos teores de clorofila, estimados pelo Medidor Porttil de Clorofilas. Os danos foram reversveis, desaparecendo gradativamente com a idade das plantas.
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New drug delivery systems have been used to increase chemotherapy efficacy due the possible drug resistance of cancer cells. Poly (lactic acid) (PLA) microparticles are able to reduce toxicity and prolong methotrexate (MTX) release. In addition, the use of PLA/poloxamer polymer blends can improve drug release due to changes in the interaction of particles with biological surfaces. The aim of this study was developing spray dried biodegradable MTX-loaded microparticles and evaluate PLA interactions with different kinds of Pluronic (PLUF127 and PLUF68) in order to modulate drug release. The variables included different drug:polymer (1:10, 1:4.5, 1:3) and polymer:copolymer ratios (25:75, 50:50, 75:25). The precision and accuracy of spray drying method was confirmed assessing drug loading into particles (75.0- 101.3%). The MTX/PLA microparticles showed spherical shape with an apparently smooth surface, which was dependent on the PLU ratio used into blends particles. XRD and thermal analysis demonstrated that the drug was homogeneously dispersed into polymer matrix, whereas the miscibility among components was dependent on the used polymer:copolymer ratio. No new drug- polymer bond was identified by FTIR analysis. The in vitro performance of MTX-loaded PLA microparticles demonstrated an extended-release profile fitted using Korsmeyer- Peppas kinetic model. The PLU accelerated drug release rate possible due PLU leached in the matrix. Nevertheless, drug release studies carried out in cell culture demonstrated the ability of PLU modulating drug release from blend microparticles. This effect was confirmed by cytotoxicity observed according to the amount of drug released as a function of time. Thus, studied PLU was able to improve the performance of spray dried MTX-loaded PLA microparticles, which can be successfully used as carries for modulated drug delivery with potential in vivo application
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Os sistemas de produo transgnicos, assim como os convencionais, exigem, alm do controle qumico, a adoo de outras estratgias de manejo de plantas daninhas. Objetivou-se, com este trabalho, avaliar o controle qumico de plantas daninhas, em soja geneticamente modificada (transgnica) tolerante ao herbicida glyphosate associado a coberturas vegetais, na entressafra. O experimento foi instalado em rea experimental da FCAV/Unesp, Jaboticabal (SP). O delineamento experimental foi o de blocos ao acaso, em esquema de parcelas subdivididas, com quatro repeties. Nas parcelas, foram avaliadas as coberturas vegetais de Brachiaria brizantha (braquiaro cv. Marandu), Pennisetum americanum (milheto forrageiro cv. BN2) e vegetao espontnea, e, nas subparcelas, os herbicidas glyphosate, chlorimuron - ethyl + lactofen em mistura e fluazifop-p-butyl em aplicao sequencial, alm de duas testemunhas sem aplicao. A cobertura com braquiaro contribuiu para o controle qumico, exercendo supresso das plantas daninhas. A aplicao nica de 720 g e.a. ha-1de glyphosate, independentemente da cobertura vegetal utilizada na entressafra, foi suficiente para o controle adequado de Acanthospermum hispidum, Alternanthera tenella, Amaranthus sp., Bidens pilosa, Xanthium strumarium, Cenchrus echinatus, Digitaria sp. e Eleusine indica, com resultados similares ao tratamento (chlorimuron-ethyl + lactofen) + fluazifop-p-buthyl. Comparados testemunha capinada, os herbicidas testados no afetaram a altura das plantas, massa seca da parte area, massa de 100 gros e a produtividade de gros. As plantas de soja crescidas sobre os resduos vegetais de braquiaro e milheto forrageiro apresentaram maior altura, porm, nenhuma outra caracterstica avaliada na cultura foi influenciada pelas coberturas.
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O experimento foi instalado em rea de plantio comercial de soja Roundup Ready, na regio do Pontal do Paranapanema, no municpio de Euclides da Cunha Paulista-SP, localizada a 20 43' 11'' S e 50 10' 20'' W, com uma altitude de 270 m. A fase experimental foi conduzida de dezembro de 2006 a abril de 2007, sob sistema plantio direto, com uma temperatura mdia de 25 C e ndice pluviomtrico de 800 mm. O solo da rea experimental apresenta classe textural franco-argilo arenosa. Objetivou-se com este trabalho avaliar a eficcia e seletividade de glyphosate na formulao Roundup Transorb, associado aos herbicidas diclosulam, cloransulam-methyl, flumioxazina e S-metolachlor em duas modalidades de aplicao: nica, com associao do glyphosate aos herbicidas; e uma sequencial apenas com glyphosate aos 15 DAA, no manejo das plantas daninhas trapoeraba (Commelina benghalensis) e corda-de-viola (Ipomoea triloba) durante o cultivo da soja. O experimento foi instalado no delineamento de blocos ao acaso, com 12 tratamentos e quatro repeties. Os tratamentos foram distribudos em arranjo fatorial acrescido de duas testemunhas: sem capina manual e com capina manual. O arranjo fatorial 2 x 5 contemplou duas condies de aplicao dos herbicidas (nica e sequencial) e cinco herbicidas (glyphosate, glyphosate + diclosulam, glyphosate + cloransulam-methyl, glyphosate + flumioxazin e glyphosate + S-metolachlor). Nas condies de produtos, pocas de aplicao e doses, os resultados mostraram que o herbicida glyphosate aplicado em dose nica ou sequencial e suas combinaes com diclosulam e cloransulam-methyl na primeira aplicao no promovem fitointoxicao nas plantas de soja. A combinao com flumioxazin e S-metolachlor promoveu atraso no crescimento das plantas e no fechamento da cultura, em razo do efeito na altura dos indivduos e comprimento dos ramos. No tratamento com o S-metolachlor, isso pode ser explicado pelo fato de o herbicida ser registrado para controle em pr-emergncia e ter sido aplicado em ps-emergncia. Nenhum dos tratamentos influenciou significativamente a produo de gros da cultura da soja. A aplicao nica ou a complementao com aplicao sequencial de glyphosate promoveram excelente controle de Commelina benghalensis e Ipomoea triloba.
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This work presents a theoretical and numerical analysis using the transverse resonance technique (TRT) and a proposed MTRT applied in the analysis of the dispersive characteristics of microstrip lines built on truncated isotropic and anisotropic dielectric substrates. The TRT uses the transmission lines model in the transversal section of the structure, allowing to analyze its dispersive behavior. The difference between TRT and MTRT consists basically of the resonance direction. While in the TRT the resonance is calculated in the same direction of the metallic strip normal axis, the MTRT considers the resonance in the metallic strip parallel plane. Although the application of the MTRT results in a more complex equivalent circuit, its use allows some added characterization, like longitudinal section electric mode (LSE) and longitudinal section magnetic mode (LSM), microstrips with truncated substrate, or structures with different dielectric regions. A computer program using TRT and MTRT proposed in this work is implemented for the characterization of microstrips on truncated isotropic and anisotropic substrates. In this analysis, propagating and evanescent modes are considered. Thus, it is possible to characterize both the dominant and higher order modes of the structure. Numerical results are presented for the effective permittivity, characteristic impedance and relative phase velocity for microstrip lines with different parameters and dimensions of the dielectric substrate. Agreement with the results obtained in the literature are shown, as well as experimental results. In some cases, the convergence analysis is also performed by considering the limiting conditions, like particular cases of isotropic materials or structures with dielectric of infinite size found in the literature. The numerical convergence of the formulation is also analyzed. Finally, conclusions and suggestions for the continuity of this work are presented
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In this work a modification on ANFIS (Adaptive Network Based Fuzzy Inference System) structure is proposed to find a systematic method for nonlinear plants, with large operational range, identification and control, using linear local systems: models and controllers. This method is based on multiple model approach. This way, linear local models are obtained and then those models are combined by the proposed neurofuzzy structure. A metric that allows a satisfactory combination of those models is obtained after the structure training. It results on plant s global identification. A controller is projected for each local model. The global control is obtained by mixing local controllers signals. This is done by the modified ANFIS. The modification on ANFIS architecture allows the two neurofuzzy structures knowledge sharing. So the same metric obtained to combine models can be used to combine controllers. Two cases study are used to validate the new ANFIS structure. The knowledge sharing is evaluated in the second case study. It shows that just one modified ANFIS structure is necessary to combine linear models to identify, a nonlinear plant, and combine linear controllers to control this plant. The proposed method allows the usage of any identification and control techniques for local models and local controllers obtaining. It also reduces the complexity of ANFIS usage for identification and control. This work has prioritized simpler techniques for the identification and control systems to simplify the use of the method
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In last decades, neural networks have been established as a major tool for the identification of nonlinear systems. Among the various types of networks used in identification, one that can be highlighted is the wavelet neural network (WNN). This network combines the characteristics of wavelet multiresolution theory with learning ability and generalization of neural networks usually, providing more accurate models than those ones obtained by traditional networks. An extension of WNN networks is to combine the neuro-fuzzy ANFIS (Adaptive Network Based Fuzzy Inference System) structure with wavelets, leading to generate the Fuzzy Wavelet Neural Network - FWNN structure. This network is very similar to ANFIS networks, with the difference that traditional polynomials present in consequent of this network are replaced by WNN networks. This paper proposes the identification of nonlinear dynamical systems from a network FWNN modified. In the proposed structure, functions only wavelets are used in the consequent. Thus, it is possible to obtain a simplification of the structure, reducing the number of adjustable parameters of the network. To evaluate the performance of network FWNN with this modification, an analysis of network performance is made, verifying advantages, disadvantages and cost effectiveness when compared to other existing FWNN structures in literature. The evaluations are carried out via the identification of two simulated systems traditionally found in the literature and a real nonlinear system, consisting of a nonlinear multi section tank. Finally, the network is used to infer values of temperature and humidity inside of a neonatal incubator. The execution of such analyzes is based on various criteria, like: mean squared error, number of training epochs, number of adjustable parameters, the variation of the mean square error, among others. The results found show the generalization ability of the modified structure, despite the simplification performed
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O objetivo deste trabalho foi avaliar o efeito da irradiao gama associada atmosfera modificada passiva na qualidade ps-colheita de goiabas 'Pedro Sato', verificando suas caractersticas fsico-qumicas. Foram utilizadas goiabas provenientes da regio de Vista Alegre do Alto-SP,Brasil. Aps a colheita, as goiabas foram imediatamente transportadas ao Laboratrio de Frutas e Hortalias, pertencente ao Departamento de Gesto e Tecnologia Agroindustrial, da Faculdade de Cincias Agronmicas - UNESP - Cmpus de Botucatu-SP, onde foram armazenadas a 10C e 90-95%UR, em cmara frigorfica, por 28 dias. Os tratamentos foram: controle 1 (sem embalagem e sem irradiao); controle 2 (embalagem de poliestireno (PS) + polietileno de baixa densidade (PEBD) e sem irradiao); tratamento 1 (PS+PEBD e 0,2kGy); tratamento 2 (PS+PEBD e 0,6kGy), e tratamento 3 (PS+PEBD e 1,0kGy). As anlises realizadas foram: firmeza, slidos solveis (SS), acidez titulvel (AT) e ndice de maturao. Foi utilizado o delineamento inteiramente casualizado, com esquema fatorial 5 x 5 (tratamento x tempo). Concluiu-se que as altas doses de irradiao promoveram efeito negativo nas caractersticas fsico-qumicas da goiaba 'Pedro Sato', e que apenas a menor dose utilizada (0,2kGy) associada atmosfera modificada conservou frutos com maior qualidade e aceitabilidade, indicado por maiores ndice de maturao e teor de slidos solveis obtidos.
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Actually, surveys have been developed for obtaining new materials and methodologies that aim to minimize environmental problems due to discharges of industrial effluents contaminated with heavy metals. The adsorption has been used as an alternative technology effectively, economically viable and potentially important for the reduction of metals, especially when using natural adsorbents such as certain types of clay. Chitosan, a polymer of natural origin, present in the shells of crustaceans and insects, has also been used for this purpose. Among the clays, vermiculite is distinguished by its good ion exchange capacity and in its expanded form enhances its properties by greatly increasing its specific surface. This study aimed to evaluate the functionality of the hybrid material obtained through the modification of expanded vermiculite with chitosan in the removal of lead ions (II) in aqueous solution. The material was characterized by infrared spectroscopy (IR) in order to evaluate the efficiency of modification of matrix, the vermiculite, the organic material, chitosan. The thermal stability of the material and the ratio clay / polymer was evaluated by thermogravimetry. To evaluate the surface of the material was used in scanning electron microscopy (SEM) and (BET). The BET analysis revealed a significant increase in surface area of vermiculite that after interaction with chitosan, was obtained a value of 21, 6156 m2 / g. Adsorption tests were performed according to the particle size, concentration and time. The results show that the capacity of removal of ions through the vermiculite was on average 88.4% for lead in concentrations ranging from 20-200 mg / L and 64.2% in the concentration range of 1000 mg / L. Regarding the particle size, there was an increase in adsorption with decreasing particle size. In fuction to the time of contact, was observed adsorption equilibrium in 60 minutes with adsorption capacity. The data of the isotherms were fitted to equation Freundlich. The kinetic study of adsorption showed that the pseudo second- order model best describes the adsorption adsorption, having been found following values K2=0,024 g. mg-1 min-1and Qmax=25,75 mg/g, value very close to the calculated Qe = 26.31 mg / g. From the results we can conclude that the material can be used in wastewater treatment systems as a source of metal ions adsorbent due to its high adsorption capacity
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The present work investigates some consequences that arise from the use of a modifed lagrangean for the eletromagnetic feld in two diferent contexts: a spatially homogeneous and isotropic universe whose dynamics is driven by a magnetic feld plus a cosmological parameter A, and the problem of a static and charged point mass (charged black hole). In the cosmological case, three diferent general solutions were derived. The first, with a null cosmological parameter A, generalizes a particular solution obtained by Novello et al [gr-qc/9806076]. The second one admits a constant A and the third one allows A to be a time-dependent parameter that sustains a constant magnetic feld. The first two solutions are non-singular and exhibit in ationary periods. The third case studied shows an in ationary dynamics except for a short period of time. As for the problem of a charged point mass, the solutions of the Einstein-Maxwell equations are obtained and compared with the standard Reissner-Nordstrom solution. Contrary to what happens in the cosmological case, the physical singularity is not removed
