The TFT saturation mobility did not change with light intensity, remaining constant at 1.2×10(-4) cm(2)/V s. The TFT ON current instead increased

due to a shift in the turn-on voltage V-T. This changed from -27 to -20 V over the measured light intensity range, initially changing rapidly but then saturating at higher intensity values. Contact resistance R-C measurements showed large values in the dark. R-C rapidly decreases with increasing light intensity, again saturating at higher values. From these results, we propose a phototransistor Selleck TPX-0005 model in which illumination varies the device performance by effecting injection. By considering this shift in R-C as photoassisted barrier lowering which additionally varies the width of the region depleted of carriers between the injecting interface and the channel, it is possible to explain the observed shift in V-T as a change in the fraction of the gate bias dropped across the contact capacitance C-C. By operating

the phototransistor at a value of V-g=-5 V (below V-T), it was possible to achieve a highly linear response of the photocurrent with light intensity. Alternatively, by operating at a value of V-g=-40 V (above V-T), it was possible to maximize the photoresponsivity within the measured range. A photoresponsivity of 18.5 A/W at 5 mu W/cm(2) light intensity was achieved.”
“Purpose: Radon is natural radioactive noble gas that can be found in soil, water, outdoor and indoor air. Exposure to radon accounts for more

that PLX-4720 50% of the annual effective dose of natural radioactivity. The purpose of the current review is to summarize recent literature and evaluate the weight of evidence on the adverse health effects of radon. Conclusions: Radon is an established human lung carcinogen based on human epidemiological data supported by experimental evidence of mutagenesis studies in cell culture and laboratory animals. Extrapolation from cohort studies on miners suggested that radon is the second leading cause of lung cancer death after tobacco smoke. The majority of studies on the relationship between radon and other types of cancers showed weak or no association. FDA-approved Drug Library purchase Low levels of radon can be found in drinking water; however, radon released during water usage adds small quantities to indoor radon concentration. Studies showed that the risk of stomach cancer and other gastrointestinal malignancies from radon in drinking water is small. Studies of the genetic and cytogenetic effects of indoor radon yielded equivocal results; while radon exposure in miners induces gene mutations and chromosomal aberrations. Numerous invitro cytogenetic studies demonstrated that radon induces different types of genetic and cytogenetic damage that is likely to play a role in radon lung carcinogenesis.