BRIAN H. DAVISON Oak Ridge National Laboratory MARK FINKELSTEIN National Renewable Energy Laboratory CHARLES E. WYMAN Oak Ridge National Laboratory The Eighteenth Symposium on Biotechnology for Fuels and Chemi cals continues to provide a forum for the presentation of research results and the exchange of ideas on advances in biotechnology for the produc tion of fuels and chemicals. Although the emphasis is on utilization of renewable resources, the scope of the Symposium is broader than this and includes bioconversion of fossil fuels and syngas and the new area of conversions in nonaqueous...

Early studies by Pendleton and West (1) in 1932 demonstrated that urea moved from the blood into the small intestine in uremic dogs. In 1946, Twiss and Kolff (2) showed in uremic patients that urea could be removed when an isotonic solution was perfused through an isolated in testinalloop. Since these early studies had demonstrated the presence of urea and its removal from the gastrointestinal tract, Yatzidis (3) in 1964 investigated the use of activated charcoal for the removal of uremic wastes from the intestinal tract. In addition to Yatzidis' studies with char coal, other investigations...