9 THz) by time-domain spectroscopy. From the frequency
dependence of the complex scattering parameters, we show the possibility to close the gap between the left-and right-handed dispersion branches by increasing the number of layers from 3 to 5. Cell Cycle inhibitor Such a demonstration paves the way of balance composite propagation characteristics with a gapless transition between the negative and positive values of refractive index at a frequency of 0.5 THz. (C) 2010 American Institute of Physics. [doi:10.1063/1.3374703]“
“Purpose: To estimate cumulative radiation exposure and lifetime attributable risk (LAR) of radiation-induced cancer from computed tomographic (CT) scanning of adult patients at a tertiary care academic medical center.
Materials and Methods: This HIPAA-compliant study was approved by the institutional find more review board with waiver of informed consent. The cohort comprised 31 462 patients who underwent diagnostic CT in 2007
and had undergone 190 712 CT examinations over the prior 22 years. Each patient’s cumulative CT radiation exposure was estimated by summing typical CT effective doses, and the Biological Effects of Ionizing Radiation (BEIR) VII methodology was used to estimate LAR on the basis of sex and age at each exposure. Billing ICD9 codes and electronic order entry information were used to stratify patients with LAR greater than 1%.
Results: Thirty-three percent of patients underwent five or more lifetime CT examinations, and 5% underwent between 22 and 132 examinations. Fifteen percent received estimated cumulative effective doses of more than 100 mSv, and 4% received between 250 and 1375 mSv. Associated LAR had mean and maximum values of 0.3% and 12% for cancer incidence and 0.2% and 6.8% YM155 for cancer mortality, respectively. CT exposures were estimated to produce 0.7% of total expected baseline cancer incidence and 1% of total cancer mortality. Seven percent of the cohort had estimated LAR greater than 1%, of which 40% had either no malignancy history or a cancer history
without evidence of residual disease.
Conclusion: Cumulative CT radiation exposure added incrementally to baseline cancer risk in the cohort. While most patients accrue low radiation-induced cancer risks, a subgroup is potentially at higher risk due to recurrent CT imaging. (c) RSNA, 2009″
“Quinapril undergoes a significant degradation in the solid state, specially in the presence of humidity, temperature and pharmaceutical excipients. Since dissolution increases the degradation, hydrolytic reactions are among the most common processes involved in drug degradation. Improving the knowledge regarding drug stability, particularly concerning the critical factors that can influence the stability of the active substance in solutions, such as the temperature, the pH and the concentration of catalytic species usually acids or bases are essential for pharmaceutical use.