1258 June 2013 NITROUS oxide has long been known to be an impotent and unpredictable human anesthetic.1 In this issue of the journal, Chen et al.2 report that nitrous oxide in clinical use is a potent and predictable human genotoxin. The authors observe that maintenance of anesthesia with 70% nitrous oxide and sevoflurane in patients undergoing colorectal surgery doubles the incidence of DNA da...

In the present work, the non-spherical grain characteristics of comet Halley are analysed using the T-matrix method at λ= 0.365,0.485 and 0.684μm respectively. In order to analyse the polarisation data of comet Halley, the dust size distribution function derived by Das et al. (2004) for comet Halley is used in the present work. The size range of the grains is taken to be 0.01μm≤ s ≤ 3μm. Using ...

background apoptosis or programmed cell death is an essential process for elimination of damaged cells. also, induction of apoptosis is fundamental for treating cancer. screening for agents that induce apoptosis in tumor cells help in the development of novel agents for cancer treatment. numerous studies suggest that the exposure of tumor cells to statins can lead to cell death via two separate...

OBJECTIVE To assess the genotoxic activity of N-nitroso diethylamine (NDEA), maleic hydrazide (MH), and ethyl methane sulfonate (EMS) using two systems: the comet assay on nuclei from Tradescantia, and the pink mutation test on Tradescantia staminal hairs (clone 4430). MATERIAL AND METHODS Tradescantia cups was obtained from Laboratorio de Citogenética y Mutagénesis del Centro de Ciencias de ...

Evolution of gas and dust distributions following a spatially and temporally localized comet outburst was calculated using a hybrid kinetic hydrodynamic method. It was found that a comet outburst resulted in significantly increased dust terminal velocities. As these higher terminal velocity values result in larger apex distances, therefore the outburst generates distinct dust envelopes in front...

Meteor showers on the Earth occur at well known times, and are associated with the decay of comets or other minor bodies whose orbital paths pass close to the Earth’s trajectory. On the surface, determining the closest proximity of two orbital paths appears to be a computationally intensive procedure. This paper describes a simple geometric method for determining the proximity between the orbit...