A sensitive, reliable and specific LC-MS-MS method was developed and validated for the identification and quantitation of all-trans retinoic acid (ATRA) in human plasma. Acitretin was used as the internal standard (IS). After liquid-liquid extraction of 500 μL plasma with methyl tert-butyl ether (MTBE), ATRA and the IS were chromatographed on a HyPURITY C18 column (150 mm × 2.1 mm, 5 μm) with t...

Aquifer microbial communities can be investigated using Bio-traps(®) ("bio-traps"), passive samplers containing Bio-Sep(®) beads ("bio-beads") that are deployed in monitoring wells to be colonized by bacteria delivered via groundwater flow through the well. When bio-beads are "baited" with organic contaminants enriched in (13)C, stable isotope probing allows assessment of the composition and ac...

Cholelithiasis is a prevalent problem in the United States with 14% or more adults affected. Definitive treatment of cholelithiasis is cholecystectomy. When cholecystectomy yields minimal resolution treatment options include expectant management of asymptomatic gallstones or endoscopic retrograde cholangiopancreatogram. We present a case of intrahepatic biliary casts where surgical option was n...

Experiments have yielded a number of important insights into the energy distribution, sparging and oxidation of methyl tert-butyl ether (MTBE), benzene, ethylbenzene, toluene, m- and p-xylene, and o-xylene (BTEX) in a dense medium plasma reactor (DMPR). It has been found that the DMPR transferred a relatively small amount of electrical energy, approximately 4% in the form of sensible heat, to t...

Printed 1/2/2001 2 Based on an evaluation of the physicochemical and toxicological properties of Methyl tert-Butyl Ether (MTBE), as well as an ex post-facto cost and benefit analysis, it has become clear that there are less expensive and disruptive approaches to achieving the goals of the 1990 Clean Air Act Amendments with regards to gasoline-powered mobile sources. However, before jumping to t...

Banana varieties have a significant effect on the reducing sugar content in peel. In recent years, potential efforts been directed towards utilization of cheap renewable agricultural resources, such as banana peel waste alternative substrate for ethanol production. Various conversion pathways are compared from technical, economic, and environmental points view. This study also deals mainly with...