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Uncompatibilized and compatibilized blends of poly(ethylene terephthalate) (PET) and high-density polyethylene (HDPE) (50:50 PET/HDPE) have been prepared and characterized. A commercial grade of ethylene/methacrylic acid copolymer was used as compatibilizing agent and added to the blends in two different proportions, 1% and 7%. Compounded blends were processed following three different procedures: compression molding, extrusion, and extrusion followed by annealing. In every case, there is evidence that suggests that HDPE constitutes the matrix and PET is the dispersed phase. The PET phase shape was related to the processing procedure of the blends. PET adopted a globular morphology in the compression molded samples but it took the form of microfibers (microfibrillar-like reinforced composites) in extruded samples, which were flattened during the postextrusion annealing process. According to the results obtained in tensile and fracture tests, extruded blends having 7% of ethylene/methacrylic acid copolymer appeared as the optimum combination of processing method and compatibilizer content. POLYM. ENG. SCI., 45: 354-363, 2005. [c] 2005 Society of Plastics Engineers, INTRODUCTION Poly (ethylene terephthalate) (PET) and polyethylenes are extensively used in packaging of consumer and industrial products, being the most found in urban waste streams. One of the best ways [...]

OBJECTIVE: To investigate whether central nervous system (CNS) stimulants used for the treatment of attention deficit hyperactivity disorder (ADHD) are associated with the development of Raynaud's syndrome (RS). METHODS: A case-control design was used for this study. All patients seen in a pediatric rheumatology practice during a 5-year period who had signs and symptoms of RS and met diagnostic criteria for RS as determined by pulse volume recording were studied as cases. Controls were randomly selected patients at the same clinic who did not have signs or symptoms of RS. They were matched to the cases for age, sex, and time of presentation. We tested for associations between various CNS medications and presence of RS. We also evaluated differences in laboratory test results between RS cases and matched controls. RESULTS: Sixty-four patients were enrolled in the study (32 cases with RS [23 female, 9 male] and 32 control patients). McNemar's test showed a significant association between the presence of RS and past or current use of ADHD stimulants (methylphenidate and dextroamphetamine) (chi(2) = 5.00, P = 0.01). The use of other CNS medications was not found to be significantly associated with RS (chi(2) = 1.33, P = 0.25 by McNemar's test). C-reactive protein levels and erythrocyte sedimentation rates were significantly higher in controls than in cases. CONCLUSION: The results of this study indicate that there is a significant association between development of RS and therapy with CNS stimulants used for the treatment of ADHD. Although this was a small study, these findings provide preliminary evidence of an adverse effect of CNS stimulant medications in patients seen in rheumatology practice. [ABSTRACT FROM AUTHOR]

Total parenteral nutrition can offer real benefits to seriously ill patients -- but there's a price. Here's how to maximize the benefits and minimize the risks. [ABSTRACT FROM AUTHOR]