Poli-líquidos iônicos e complexos solúveis de Eu3+ e Tb3+ : bioimageamento celular seletivo

Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, Programa de Pós-Graduação em Química, 2015.

Impacto da utilização de ácido gálhico, ácido ferúlico e eugenol em modo contínuo na suscetibilidade de Pseudomonas aeruginosa

Dissertação de Mestrado, Biologia Molecular e Microbiana, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016

Estudio de los niveles de ácido úrico sérico (AUs) y su asociación con alteraciones clínicas, metabólicas y dietéticas en escolares con obesidad en el Estado de Nuevo León, México

Introducción. El ácido úrico sérico (AUs) elevado es considerado marcador de riesgo cardiometabólico. En escolares con obesidad de Nuevo León no ha sido estudiado a profundidad. Objetivo. Estudiar los niveles de AUs y su asociación con indicadores clínico-metabólicos y dietéticos en escolares con obesidad e IMC normal. Material y métodos. Estudio retrospectivo, transversal, correlacional, en 530 escolares (6-12 años) autoseleccionados del programa de Obesidad Infantil FaSPyN-UANL, 322 con obesidad y 208 con IMC normal1 . La medición de los indicadores clínicos, metabólicos y dietéticos se realizó por personal certificado2 . Hiperuricemia se consideró con AUs > 5.5 mg/dL3 . Ingesta dietética4 se determinó con el recordatorio de 24 horas y software Food Processor. Se aplicaron técnicas de normalidad (Kolmogorov-Smirnov), prueba t para dos muestras, ANOVA de dos factores, U de Mann Whitney y regresión logística binaria, en software SPSS. Resultados. Se encontró diferencia significativa (p-valor < 0.05) para género, edad y nivel medio de AUs entre escolares con obesidad e IMC normal. 24.3% de escolares con obesidad presentaron hiperuricemia. Existieron diferencias significativas entre escolares con y sin hiperuricemia para la mayoría de los indicadores. La asociación del AUs con indicadores: obesidad (OR = 4.5), género masculino (OR = 2.6), edad (OR = 2.3), triglicéridos (OR = 1.3), ingesta de: proteínas (OR = 1.7), azúcares (OR = 1.5) y fibra dietética (OR = 0.6) fueron significativos (p-valor < 0.05). Conclusiones. Los escolares con obesidad, de género masculino y mayor edad presentaron niveles más elevados de AUs. La frecuencia de hiperuricemia fue mayor a lo reportado en otras poblaciones. Los niveles de AUs se asociaron principalmente con la obesidad, género masculino, mayor edad, triglicéridos séricos elevados, ingesta excesiva de proteínas y de azúcares, e ingesta deficiente de fibra dietética, lo que destaca la importancia del AUs como marcador de riesgo metabólico y nutricio.

Influência de tratamentos térmicos no comportamento mecânico da blenda poli(metacrilato de metila) / poli(tereftalato de etileno) reciclado

Studies indicate that a variation in the degree of crystallinity of the components of a polymer blend influences the mechanical properties. This variation can be obtained by subjecting the blend to heat treatments that lead to changes in the spherulitic structure. The aim of this work is to analyze the influence of different heat treatments on the variation of the degree of crystallinity and to establish a relationship between this variation and the mechanical behavior of poly(methyl methacrylate)/poly(ethylene terephthalate) recycled (PMMA / PETrec) with and without the use of compatibilizer agent poly(methyl methacrylate-al-glycidyl methacrylate-al-ethyl acrylate) (MMAGMA- EA). All compositions were subjected to two heat treatments. T1 heat treatment the samples were treated at 130 ° C for 30 minutes and cooled in air. In T2, the samples were treated at 230 ° C for 5 minutes and cooled to approximately -10 ° C. The variation of the degree of crystallinity was determined by the proportional relationship between crystallinity and density, with the density measured by pycnometry. The mechanical behavior was verified by tensile tests with and without the presence of notches and pre-cracks, and by method of fracture toughness in plane strain (KIC). We used the scanning electron microscopy (SEM) to analyze the fracture surface of the samples. The compositions subjected to heat treatment T1, in general, showed an increase in the degree of crystallinity in tensile strength and a tendency to decrease in toughness, while compositions undergoing treatment T2 showed that the opposite behavior. Therefore, this work showed that heat treatment can give a polymer blend further diversity of its properties, this being caused by changes in the crystal structure

Processamento e caracterização da blenda poli (metacrilato de metila) (PMMA) elastomerico e poli (tereftalato de etileno) (PET) pós-consumo

This work studied the immiscible blend of elastomeric poly(methyl methacrylate) (PMMA) with poly(ethylene terephthalate) (PET) bottle grade with and without the use of compatibilizer agent, poly(methyl methacrylate-co-glycidyl methacrylate - co-ethyl acrylate) (MGE). The characterizations of torque rheometry, melt flow index measurement (MFI), measuring the density and the degree of cristallinity by pycnometry, tensile testing, method of work essential fracture (EWF), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were performed in pure polymer and blends PMMA/PET. The rheological results showed evidence of signs of chemical reaction between the epoxy group MGE with the end groups of the PET chains and also to the elastomeric phase of PMMA. The increase in the concentration of PET reduced torque and adding MGE increased the torque of the blend of PMMA/PET. The results of the MFI also show that elastomeric PMMA showed lower flow and thus higher viscosity than PET. In the results of picnometry observed that increasing the percentage of PET resulted in an increase in density and degree crystallinity of the blends PMMA/PET. The tensile test showed that increasing the percentage of PET resulted in an increase in ultimate strength and elastic modulus and decrease in elongation at break. However, in the phase inversion, where the blend showed evidence of a co-continuous morphology and also, with 30% PET dispersed phase and compatibilized with 5% MGE, there were significant results elongation at break compared to elastomeric PMMA. The applicability of the method of essential work of fracture was shown to be possible for most formulations. And it was observed that with increasing elastomeric PMMA in the formulations of the blends there was an improvement in specific amounts of essential work of fracture (We) and a decrease in the values of specific non-essential work of fracture (βWp)

Efeito da adição do poli(etileno acrilato de metila) (ema) e da fibra de linter de algodão nas propriedades do poli(tereftalato de etileno) reciclado (petrec)

The development of new materials to fill the demand of technological advances is a challenge for many researchers around the world. Strategies such as making blends and composites are promising alternatives to produce materials with different properties from those found in conventional polymers. The objective of this study is to evaluate the effect of adding the copolymer poly(ethylene methyl acrylate) (EMA) and cotton linter fibers (LB) on the properties of recycled poly(ethylene terephthalate) (PETrec) by the development of PETrec/EMA blend and PETrec/EMA/LB blend composite. In order to improve the properties of these materials were added as compatibilizers: Ethylene - methyl acrylate - glycidyl methacrylate terpolymer (EMA-GMA) and maleic anhydride grafted polyethylene (PE-g-MA). The samples were produced using a single screw extruder and then injection molded. The obtained materials were characterized by thermogravimetry (TG), melt flow index (MFI) mensurements, torque rheometry, pycnometry to determinate the density, tensile testing and scanning electron microscopy (SEM). The rheological results showed that the addition of the EMA copolymer increased the viscosity of the blend and LB reduces the viscosity of the blend composite. SEM analysis of the binary blend showed poor interfacial adhesion between the PETrec matrix and the EMA dispersed phase, as well as the blend composite of PETrec/EMA/LB also observed low adhesion with the LB fiber. The tensile tests showed that the increase of EMA percentage decreased the tensile strength and the Young s modulus, also lower EMA percentage samples had increased the elongation at break. The blend composite showed an increase in the tensile strength and in the Young`s modulus, and a decrease in the elongation at break. The blend formulations with lower EMA percentages showed better mechanical properties that agree with the particle size analysis which showed that these formulations presented a smaller diameter of the dispersed phase. The blend composite mechanical tests showed that this material is stronger and stiffer than the blend PETrec/EMA, whose properties have been reduced due to the presence of EMA rubbery phase. The use of EMA-GMA was effective in reducing the particle size of the EMA dispersed phase in the PETrec/EMA blend and PE-g-MA showed evidences of reaction with LB and physical mixture with the EMA

Efeito de argilas organofílicas na estrutura e propriedades de nanocompósitos de poli(metacrilato de metila)

Nacomposites of polymers and lamellar clayminerals, has generated high scientific and technological interest, for having mechanical properties and gas barriers differentiated of polymers and conventional composites. In this work, it was developed nanocomposites by single screw extruder and injection, utilizing commercial raw material, with the goal to investigate the quality of new developed materials. It was evaluated the influence of the content and the kind of clay in the structure and in the nanocomposites properties. It was used regular and elastomeric poly (methyl methacrylate) (Acrigel LEP 100 and Acrigel ECP800) and six montmorillonites (Cloisite 10A, 11B, 15A, 20A, 25A e 30B) at the concentration of 1% e 3% in weight. The nanocomposites were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM), colorimetric, optical transparency, flexural and tensile tests, Rockwell hardness and esclerometry. It was founded that is possible to obtain intercalated and exfoliated nanocomposites PMMA/MMT, and the top results was obtained in the materials with 1%in clay weight organophilizated with 2M2HT (Cloisite 15A and 20A) presented intercalate and hybrid morphology (exfoliated and flocullated). The ones that was produced with organophilizated clay with 2MHTL8 (Cloisite 30B) had excellent visual quality, but the majority presented hybrid morphology. In the materials processed with organophilizated clay with MT2ETOH (Cloisite 30B), there were color change and loss of transparency. It occurs improvement in a few mechanical properties, mainly in the materials produced with PMMA elastomeric (Acrigel ECP800), being more significant, the increase in the resistance to stripping in those nanocomposites

Multibiomarker assessment of cadmium-based quantum dots effects in the marine mussel Mytilus galloprovincialis

Tese de Doutoramento, Ciências do Mar, da Terra e do Ambiente, Ramo: Ciências e Tecnologias do Ambiente, Especialização em Ecotoxicologia, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016

Concordancia diagnóstica entre citología, visualización directa con ácido acético e histopatología en el diagnóstico de lesiones de cuello uterino: Centro de Salud No. 1, Cuenca y Hospital José F. Valdivieso, Santa Isabel 2004

Estudio que tiene el objetivo de determinar la concordancia diagnóstica entre la prueba de visualización con ácido (PVAA), citología e histopatología para diagnóstico de lesisones de cuello uterino. Se realizó PVAA y citología a 130 mujeres entre 20 y 89 años beneficiarias del programa DOC del MSP en el Centro de Salud No. 1 de Cuenca y el Hospsital José F. Valdivieso de Santa Isabel desde el 1 de enero hasta el 31 de diciembre de 2004. Resultados: la biopsia únicamente en 22 acetoblancas positivas. La sensibilidad de la PVAA fue del 100, igual a la biopsia (prueba de oro), pero la especificidad fue del 86.4(IC9579,9 - 92,8) debido al alto porcentaje de falsos positivos (17/22 = 77,27). El valor predictivo positivo fue del 22.7(IC952,9 - 42,5) pero el negativo del 100. La concordancia de la prueba por el índice Kappa fue del 32,8(IC9516 - 33) y la eficacia por el índice de Youden, del 86(IC9580 - 92). El cálculo de la probabilidad diagnóstica nos dio un Likelihood Ratio + de 7,35 (IC954,73 -11,4) y un LR - de 0,0 (IC950,0 - 0,4). Los resultados de Papanicolaou fueron iguales a la biopsia. Se detectó el 3,9de lesiones histológicas premalignas, el 0,8LIE de bajo grado (NIC I) y el 3,1LIE de alto grado (NIC II y NIC III). Implicaciones: la PVAA es de alta sensibilidad y mejora la tasa de detección de lesiones precancerosas con respeto a la citología convencional, pero genra inquietudes la elevada proporción de falsos positivos. Por la facilidad de realización y bajo costo resulta atractiva para medios de escasos recursos como el de la muestra

Rizobactérias produtoras de ácido indolacético e seu efeito na germinação de milho.

O objetivo deste trabalho foi isolar e selecionar rizobactérias do solo de Terra Preta de Índio e avaliar seu efeito na germinação de milho.

Reutilização de solução extratora na determinação de fibra em detergente neutro e fibra em detergente ácido.

2006

Leite Instável Não Ácido (Lina) - Variações na Composição do Leite.

2015

Análise da interação entre moléculas desenhadas a partir do ácido anacárdico e a proteína PPAR usando ferramentas in silico

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Molecular, 2016.

Avaliação do glifosato na interação entre Phakopsora pachyrhizi e Glycine max por meio do ácido Chiquímico. II: efeito curativo.

2009

Avaliação do glifosato na interação entre Phakopsora pachyrhizi e Glycine max por meio do ácido Chiquímico. I: efeito preventivo

2009