The Behavior of Glass Fiber Composites under Low Velocity Impacts.

This paper presents experimental results on the behavior of a class of glass fiber composites under low velocity impacts, in order to analyze their usage in designing low velocity impact-resistant components in car and marine industries. Also, a finite element model at the meso level (considering yarn as a compact, homogenous and isotropic material) was run with the help of Ansys Explicit Dynamics in order to point out the stages of the failure and the equivalent stress distribution on the main yarns in different layers of the composite. The composites were manufactured at laboratory scale via the laying-up and pressing method, using a quadriaxial glass fiber fabric (0°/+45°/90°/-45°) supplied by Castro Composites (Pontevedra, Spain) and an epoxy resin.

Antioxidant activity in rat models of nociceptive stress.

Unlabelled: Pain is an important problem and has been the subject of many studies in recent years.

Material And Method: The present study has investigated the response of the antioxidant defense systems in contention stress, which mimics nociceptive stress. Contention stress was made by immobilizing the rat, Wistar rats, on an operating table in a specific position with paws tied, for thirty minutes.

Effects of dietary flaxseed supplementation on renal oxidative stress in experimental diabetes.

Unlabelled: Previous results demonstrate that experimental diabetes mellitus is accompanied by increased oxidant stress within glomeruli. Evidence are emerging that dietary flaxseed supplementation can have beneficial effects on oxidative stress.

Materials And Methods: Diabetes was induced by intraperitoneal injection of streptozotocin (STZ) in male Golden Syrian hamsters, and both diabetic and control groups were fed either standard diet, or standard diet supplemented with flaxseed (15 g/100 g diet), for 20 weeks.

Characterization of some extractive fractions isolated from raw Allium cepa L. bulbs.

Unlabelled: Many recent studies have showed that onion (Allium cepa L.) has antioxidant effect which could be of great importance for prevention and treatment of different diseases: diabetes, cancer, cardiovascular and neurodegenerative disorders. The aim of this study was to investigate the antioxidant capacity of two extracts isolated from fresh onion bulbs: an hydroalcoholic extract (codified EC1) and an aqueous extract (codified EC2).

Protecting antioxidative effects of vitamins E and C in experimental physical stress.

Like every redox-active compound vitamin E may exert pro-oxidative and antioxidative effects depending on the reaction partners present. In this work we evaluated the intensity of oxidative stress produced by a physical exercise through swimming as well as of protecting action of antioxidant vitamins E and C. Antioxidant systems include antioxidant enzymes: superoxide-dismutase (SOD), catalase (CAT), glutathion peroxidase (GSH-Px), as well as of components with an antioxidant action of the reduced glutathion type (GSH) and vitamins E and C.