Application of IEEE Standard 519-1992 Harmonic limits for revenue billing meters

NRC publication: Ye

Effects of a Cell Phone Conversation on Cognitive Processing Performances

Background: The ability to apportion cognitive resources to process multiple visual and auditory stimuli is essential for human communication in competing conditions. Purpose: The purpose of the current research was to examine the effects of a cell phone conversation on a battery of cognitive tests, using both timing (RT) and accuracy (A\u27) as dependent measures. Research Design: A repeated measures ANOVA was conducted. Study Sample: Forty-two college-age (mean 22 yr) adult females with normal hearing and cognitive function participated in the study. Data Collection and Analysis: In one condition (quiet), a standardized cognitive assessment battery was administered to participants in a quiet room In the (cell phone) condition, subjects were formulating and responding to specific questions about their travel experiences during administration of the same cognitive assessment battery. The computer automatically records subject performance. Post-hoc pairwise comparisons were conducted using the Bonferroni approach. The alpha level was set at .05 for all data analysis. This method of analysis was repeated for each of the dependent measures, RT, and A\u27. Results: The results revealed a consistent, significant effect on reaction time between the two conditions. The same analysis was also conducted to examine the effect of participation in a cell phone discussion on accuracy. As with FIT, results revealed a consistent, significant affect on A\u27 between the two conditions. Conclusions: Our study supports the notion that there are differential effects of auditory distracters across cognitive spheres. For simple automatic type visual cognitive tasks, the effect is minimal. However, as visual tasks increase in difficulty, the effect of the auditory distraction is magnified, particularly when the task requires extensive division of language resource

Synthesis and biological evaluation of RGD–cryptophycin conjugates for targeted drug delivery

Cryptophycins are potent tubulin polymerization inhibitors with picomolar antiproliferative potency in vitro and activity against multidrug-resistant (MDR) cancer cells. Because of neurotoxic side effects and limited efficacy in vivo, cryptophycin-52 failed as a clinical candidate in cancer treatment. However, this class of compounds has emerged as attractive payloads for tumor-targeting applications. In this study, cryptophycin was conjugated to the cyclopeptide c(RGDfK), targeting integrin αvβ3, across the protease-cleavable Val-Cit linker and two different self-immolative spacers. Plasma metabolic stability studies in vitro showed that our selected payload displays an improved stability compared to the parent compound, while the stability of the conjugates is strongly influenced by the self-immolative moiety. Cathepsin B cleavage assays revealed that modifications in the linker lead to different drug release profiles. Antiproliferative effects of Arg-Gly-Asp (RGD)–cryptophycin conjugates were evaluated on M21 and M21-L human melanoma cell lines. The low nanomolar in vitro activity of the novel conjugates was associated with inferior selectivity for cell lines with different integrin αvβ3 expression levels. To elucidate the drug delivery process, cryptophycin was replaced by an infrared dye and the obtained conjugates were studied by confocal microscopy