exposure to cold work environment is an occupational health hazard and poses adverse effect on workers health, performance and productivity. this study was performed in a cold food-storage warehouse complex in tehran-iran in order to evaluate the workers' exposure to cold stress. twenty nine exposed workers and 33 non-exposed workers as control subject were included in this study. climatic fact...

Cold denaturation is a general property of globular proteins, but it is difficult to directly characterize because the transition temperature of protein cold denaturation, T(c), is often below the freezing point of water. As a result, studies of protein cold denaturation are often facilitated by addition of denaturants, using destabilizing pHs or extremes of pressure, or reverse micelle encapsu...

Allostery is vital to the function of many proteins. In some cases, rather than a direct steric effect, mutual modulation of ligand binding at spatially separated sites may be achieved through a change in protein dynamics. Thus changes in vibrational modes of the protein, rather than conformational changes, allow different ligand sites to communicate. Evidence for such an effect has been found ...

Temperature sensing is essential for the survival of living cells. The membrane-bound thermosensor DesK from Bacillus subtilis is a key representative of histidine kinases receptors able to remodel membrane lipid composition when the temperature drops below ~30°C. Although the receptor is well studied, a central issue remains: how does the compositional and functional diversity of the surroundi...

This paper presents the review of the effects of operating parameters on the photocatalytic degradation of textile dyes using TiO2-based photocatalysts. It further examines various methods used in the preparations of the considered photocatalysts. The findings revealed that various parameters, such as the initial pH of the solution to be degraded, oxidizing agents, temperature at which the cata...

A dynamical model is presented for chiral change in DNA molecules. The model is an extension of the conventional elastic model, which incorporates the structure of base pairs and uses a spinor representation for the DNA configuration together with a gauge principle. Motivated by a recent experiment reporting chiral transitions between right-handed B-DNA and left-handed Z-DNA [Lee et al., Proc. ...

To better evaluate patient contribution in antibiotic use, we questioned 5379 subjects from 9 countries. Antibiotics are perceived as strong, efficient drugs, but they are believed to undermine immunity. Interviewees believe that most respiratory infections, except the common cold, require antibiotic therapy, and 11% of them had to exaggerate their symptoms to get an antibiotic prescription fro...