Fabricação e caracterização estrutural de filmes de materiais poliméricos visando a aplicação como biomateriais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Encontrabilidade da informação: contributo para uma conceituação no campo da Ciência da Informação

Pós-graduação em Ciência da Informação - FFC

Análise de algumas proteinas miofibrilares envolvidas na maciez da carne em bovinos de corte

Pós-graduação em Zootecnia - FMVZ

Identificação e quantificação das proteínas miofibrilares, isoformas da cadeia pesada de miosina (MyHC) e o amaciamento da carne de bovinos Nelore (Bos indicus)

Pós-graduação em Genética e Melhoramento Animal - FCAV

The Effects of Weathering Exposure on the Physical, Mechanical, and Thermal Properties of High-density Polyethylene and Poly (Vinyl Chloride)

This paper presents results describing the physical, mechanical, and thermal properties (melt flow index - MFI and oxidative induction time - OIT) of high density polyethylene and poly (vinyl chloride) after weathering exposure (6, 12, 18, and 30 months). The materials exposed were geomembranes of two thicknesses: 1.0 and 2.0 mm (PVC) and 0.8 and 2.5 mm (HDPE). The climate parameters (average) obtained were 25 degrees C (temperature), 93 mm (precipitation), 66% (relative humidity), and 19 MJ/m(2). day (intensity of global radiation). Some results showed, for instance, that the behavior of the geomembranes changed after the exposures. A few minor variations in physical properties occurred. The density and thickness, for instance, varied 0.5-1.0% (average) for both the PVC and HDPE geomembranes. The mechanical properties changed as a function of the period of exposure. In general, some decreases were verified by the deformation of PVC. The samples became more rigid. In contrast, HDPE geomembranes became more ductile. Despite the variations in elasticity, some increases in deformability were verified. An MFI test showed some degradation in HDPE geomembranes. OIT tests revealed small values for both intact and exposed samples.

Physical and mechanical characterization of a recycled polypropylene and wood flour without additives

Recycled polymer matrix composites reinforced with wood flour can be a viable alternative for the replacement of wood and virgin polymers in materials used in floors, door frames, windows and external cladding. The objective of this research was to determine some physical and mechanical parameters of composite made with Pinus taeda and elliottii wood flour (WF) and recycled polypropylene (PP), without the use of compatibilizers or additives. The composites were separated into four traits, namely 100% PP, 90% PP with 10%, WF 80% PP with 20% WF and 70 % PP with 30% WF. The characterization of the composite followed the standards ASTM D-638-10, ASTM D256-00, ASTM D570 -98, ASTM D1238 -10 and ASTM G 155-05, it was also employed the surface analysis by scanning electron microscopy. The dimensional stability tests showed satisfactory results. Even the composite with a higher percentage of wood flour (30%) had a flow index of 10 MFI, considered compatible with that observed for PP (polypropylene) virgin by standard ASTM D 1238-10. The inclusion of wood flour (FM) afforded composites with good mechanical characteristics which can be applied in manufacture of different materials, specifically employed outdoors.

Condição corporal e jejum sobre o metabolismo energético e crescimento de juvenis de pacu

Pós-graduação em Zootecnia - FCAV

Estocagem tecidual e utilização de lipídeos em Matrinxã, Brycon cephalus (Günther, 1869)

Lipids have important biological functions, suchas membrane constituents, hormone precursors, and are efficient energy reserves, due to thers high caloric content. In fish, but not in mammals, lipid storage patterns are quite diverse. The aim of this study was to determine lipid distribution in somatic and reproductive tissues of matrinxã, Brycon cephalus, both male and female, highlighting somatic indices related to lipid dynamics. From Oct 98 to Jan 99, a total of 174 fish (8-12 each month) were sampled. After fish anesthesia, heparinized blood was collected for plasma triacylglycerol determination. Fish were individually weighed and measured, and liver, gonads and visceral fat were collected and weighed for HSI (hepatosomatic index), GSI (gonad somatic index) and MFI (mesenteric fat index) calculation. The highest values of total lipids were found in red muscle (about 18%), liver and gonads (about 16.5%). The white muscle had a lower concentration (2.5%). Analyses of variance of HSI and MFI showed fluctuations along the experimental period with lowest concentrations in the periods of highest temperatures. Matrinxã store lipids in several body tissues, including mesenteric fat, liver, muscles and gonads.

One-step glycerol oxidehydration to acrylic acid on multifunctional zeolite catalysts

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Características qualitativas da carne de frango de corte proveniente de diferentes sistemas de produção

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Degradação de geomembranas de polietileno de alta densidade (HDPE) após exposição à intempérie e lixívia

This paper presents some results of MFI and OIT tests performed on HDPE geomembranes of 0,8 and 2,5 mm that were exposed to weathering effects and leachate after 30 months (2,5 years). The aim of this work is the evaluation of the oxidative degradation process by comparison of fresh and exposed samples results. The expositing and tests were performed according the following standards recommendations: ASTM D1435 (weathering), ASTM D5747 e D5322 (leachate), ASTM D1238 (MFI) e D3895 (OIT). The results shows, for instance, that the MFI values presented high increases on the HDPE (2.5 mm) showing that polymeric chain break occurred for both exposures and, therefore, oxidative degradation. Concerning the OIT values all the geomembranes presented very low values even in the fresh samples. This demonstrates that there wasn’t an antioxidant package appropriate for these membranes.

Effects of physical activity levels on fatigue perception in patients with Parkinson's disease and neurologically healthy individuals

Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical activity practice, there are only few studies that verified the influence of the levels of physical activity on fatigue in patients with PD. Objective: The aim of this study was to compare perception of fatigue between individuals with PD and neurologically healthy individuals (control group), considering the physical activity levels; and to verify the relation between physical activity levels and fatigue dimensions for individuals with PD and control group. Methods: Eighty individuals (40 patients with PD and 40 control individuals) participated in this study. Physical activity levels were evaluated through Modified Baecke Questionnaire for Older Adults. Multidimensional Fatigue Inventory (MFI) was used in order to evaluate fatigue dimensions (general, physical and mental fatigue, reduced motivation and activity). MANOVA two-way and Pearson linear correlation test were performed to analyze the data. Results: Patients with PD presented higher levels of fatigue, in all dimensions evaluated by MFI, comparing to control individuals. There was no association between physical activity levels and perception of fatigue for patients with PD and control individuals. Conclusion: Patients with PD showed increased perception of fatigue when compared to control individuals, due to PD characteristics. In addition, the perception of fatigue’s symptom was not influenced and had no relation by the level of physical activity.

Valores nutricionais e qualitativos de carnes bovinas (Longissimus thoracis) provenientes de sistemas de produção orgânica e convencional

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)