STRESS-INDUCED ENVIRONMENT

While many biological molecules may be targets for oxidant stress and free radicals, it is clear that the cell membrane and its associated proteins may be particularly vulnerable. The ability of the cell to control its intracellular ionic environment as well as its ability to maintain a polarized membrane potential and electrical excitability depends on the activity of ion-translocating proteins such as channels, pumps and exchangers. Either direct or indirect disturbances of the activity of these ion translocators must ultimately underlie reperfiision and oxidant stress-induced arrhythmias in the heart. A number of studies have therefore investigated the effects of free radicals and oxidant stress on cellular electrophysiology and the activity of key membrane-bound ion translocating proteins. 

Abbasi, S.A. and R. Soni. 1983. Stress-induced enhancement of reproduction in earthworm Octochaetus pattoni exposed to chromium (VI) and mercury (II) — implications in environmental management. Int. Jour. Environ. Stud. 22 43-47. 

Verma, S.R., S. Rani, and R.C. Dalela. 1982b. Indicators of stress induced by pesticides in Mystus vittatus haematological parameters. Indian Jour. Environ. Health 24 58-65. 

Collen J, Davison IR (1999c) Stress tolerance and reactive oxygen metabolism in the intertidal red seaweeds Mastocarpus stellatus and Chondrus crispus. Plant Cell Environ 22 1143-1151 Collen J, Pedersen M, Bornman CH (1994) A stress-induced oxidative burst in Eucheuma platycladum (Rhodophyta). Physiol Plant 92 417 122 Collen J, Roeder V, Rousvoal S, Collin O, Kloareg B, Boyen C (2006a) An expressed sequence tag analysis of thallus and regenerating protoplasts of Chondrus crispus (Gigartinales, Rhodophyceae). J Phycol 42 104-112... 

Yildiz D, Liu Y-S, Ercal N, Armstrong DW (1999) Comparison of pure nicotine- and smokeless tobacco extract-induced toxicities and oxidative stress. Arch Environ Contam Toxicol 37 434-439... 

Imumorin IG, Dong Y, Zhu H, et al. A gene-environment interaction model of stress-induced hypertension. Cardiovasc Toxicol. 2005 5 109-132. 

The only allowed motion is the exchange of the vacancy with one of its neighboring atoms. The exchange rate depends on the local environment, i.e. on the relative position of the vacancy and the impurity atom. This takes into account the effect of the lattice stress induced by the tracer atom on the energy landscape observed by the vacancy. Each rate is simply proportional to the Boltzmann factor e-AE/kBT wjjere is the activation energy for the considered diffusional move and kBTis the thermal... 

The organism should be successfully maintained in the laboratory environment and available in sufficient quantities. Many species do not fare well in the laboratory our lack of knowledge of the exact nutritional requirements, overcrowding, and stress induced by the mere presence of laboratory personnel often make certain species unsuitable for toxicity testing. 

Ceramic/metal functionally graded material (FGM) has been developed as a super heat-resistant material used in ultra-high temperature and great temperature gradient environment since 1987 A FGM usually comprises of two or more different material components and has a constitutional gradation over macroscopic distances. The gradual change of constitution between the two sides of FGM can eliminate the traditional joint interface and relax the thermal stress induced by the temperature variation both in fabrication and in service. 

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