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Tanay Chattopadhyay Cláudia Reis Paulo André António Teixeira 《Optics Communications》2012,285(9):2266-2275
A novel scheme for an all-optical clocked D flip-flop, with very low complexity, is proposed and numerically demonstrated. This new flip-flop configuration is based on a semiconductor optical amplifier — Mach–Zehnder interferometer (SOA-MZI), with a feedback loop, and presents two stable states determined by the phase shift between the two MZI arms. 相似文献
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Cardoso Daisy Alves Valle Eliana Maíra Agostini Codognoto Lucia 《Journal of Solid State Electrochemistry》2018,22(5):1549-1555
Journal of Solid State Electrochemistry - In this work, the interaction of the pesticide methyl parathion (MP) with the lead metal ion was evaluated using a carbon electrode reused from a zinc... 相似文献
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Kirill Kulish Cosimo Boldrini Dr. Marta Castiñeira Reis Dr. Juana M. Pérez Prof. Dr. Syuzanna R. Harutyunyan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15843-15846
Two-step dearomative functionalization of naphthols promoted by Lewis acids and copper(I) catalysis was developed. Initially, Lewis acid complexation inverted the electronic properties of the ring and established an equilibrium with the dearomatized counterpart. Subsequent trapping of the dearomatized intermediate with organometallics as well as organophosphines was demonstrated and provided the corresponding dearomatized products. 相似文献
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Determination of fexofenadine in Hank's balanced salt solution by high‐performance liquid chromatography with ultraviolet detection: application to Caco‐2 cell permeability studies
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Marco Antônio dos. Reis Júnior Ana Cláudia Miranda de Faria Eudes da. Silva Velozo Teresa Dalla Costa Frank Pereira de Andrade Whocely Victor de Castro 《Biomedical chromatography : BMC》2015,29(4):537-544
The drug‐transporting proteins can affect the pharmacokinetics and pharmacodymanics of many drugs, resulting in an erratic and unpredictable pharmacological response. The Caco‐2 monolayer is routinely applied to investigate the carrier‐mediated transport of drugs. Therefore, the selection of a marker compound able to characterize the activity of such transporters is crucial. Fexofenadine (FEX), a P‐gp/OATP substrate, can be considered a suitable probe. However, in order to use be used as a marker compound, it is mandatory to develop an analytical method able to quantify this drug during the in vitro permeability assay. An HPLC method with ultraviolet detection was developed; the mobile phase consisted of phosphate buffer (pH 3.2) containing 10 m m of sodium octanosulphonate and acetonitrile (60:40) and the flow rate was set at 1.2 mL/min. Fexofenadine was eluted at 40°C, the retention time was about 4.6 min. The LOD and LOQ values were 1.9 and 6.2 ng/mL, respectively. Verapamil and ketoconazole, the most common P‐gp inhibitors, were eluted as distinct peaks of that corresponding to fexofenadine The method was successfully applied to quantify the amount of FEX transported across the Caco‐2 monolayer and could be an additional tool for those investigating the role of membrane transporters on drug absorption. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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