Chemiluminescence was used to as a tool to assess the increase in the polypropylene stability to thermo-oxidative degradation. A significant increase in the value of oxygen induction time with the initial concentration of natural antioxidants tested under isothermal conditions at 140, 150 and 160 degrees C was observed. A comparison at the same concentration level (0.1 wt %) between the three antioxidants showed an order of stabilizing efficiency as: alpha-tocopherol > Irganox

(R) 1076 > hydroxytyrosol, but all them showed clearly their stabilization performance in polypropylene. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 3393-3399, 2011″
“In this study, full coincidence between impedance spectroscopy and transient photovoltage techniques in measuring recombination LY3039478 ic50 kinetics of photogenerated charge carriers in inverted polymer: fullerene organic solar cells with ZnO hole-blocking layer is reported. Carrier lifetime exhibits values at illumination intensities near 1 sun within the microseconds time scale. Photogenerated

charge carrier density attains values within 10(15)-10(16) cm(-3). Decay kinetics is analyzed by means of a bimolecular recombination law with a recombination coefficient slightly dependent on the charge density, which lies within the order of k similar to 10(-12) cm(3) s(-1). It is also demonstrated that inverted-processed cells exhibit capacitance, recombination resistance, and lifetime parameters comparable to those extracted from Fedratinib in vivo regular cells, despite the great differences between the contact structures of these kinds of devices. (C) 2011 American Institute

of Physics. [doi: 10.1063/1.3561437]“
“Purpose: To estimate the correlation between the negative appendectomy FK228 rate (NAR) and the rate of preoperative computed tomography (CT) in patients suspected of having acute appendicitis who presented to the emergency department during an 18-year period.

Materials and Methods: This retrospective institutional review board-approved, HIPAA-compliant study was performed in a 719-bed tertiary care adult teaching hospital with 58 000 annual emergency department visits. The authors obtained a waiver of informed consent and used the medical records system to compare patients suspected of having appendicitis who presented to the emergency department between 2003 and 2007 to those who presented between 1990 and 1994, the period just before CT became commonly used at the authors’ institution for the evaluation of appendicitis. Surgical and pathology reports were reviewed to determine the NAR, and the authors queried the radiology databases to determine the proportion of appendectomy patients who underwent preoperative imaging. Outcome measures included the NAR, the proportion of appendectomy patients who underwent preoperative CT, and the annual number of appendectomies performed.