Cholangiocarcinoma

Exploratory laparotomy is frequently used to diagnose, treat, or palliate cholangiocarcinoma although surgery is rarely curative. In light of newly developed percutaneous and endoscopic approaches to diagnosis and therapy, we reviewed our experience with 35 cases of cholangiocarcinoma diagnosed and treated at the University of Michigan Medical Center from 1979 to 1984. Percutaneous transhepatic cholangiography (PTCA) was performed in 34 cases of which only four were resectable. All 22 patients who had preoperative cholangiograms suggesting unresectability had confirmation of this at surgery. Surgical palliation was accomplished with a combination of internal and percutaneous drainage in most cases. Angiographic, cytologic, and laboratory data are presented. PTCA accurately predicted unresectability of cholangiocarcinoma and is superior to angiography in this respect. In patients with cholangiocarcinoma, percutaneous and endoscopic approaches offer alternatives to surgery for diagnosis and palliation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44406/1/10620_2005_Article_BF01798361.pd

Co-Design of an active suspension using simultaneous dynamic optimization",

Design of physical systems and associated control systems are coupled tasks; design methods that manage this interaction explicitly can produce system-optimal designs, whereas conventional sequential processes may not. Here, we explore a new technique for combined physical and control system design (co-design) based on a simultaneous dynamic optimization approach known as direct transcription, which transforms infinitedimensional control design problems into finite-dimensional nonlinear programming problems. While direct transcription problem dimension is often large, sparse problem structures and fine-grained parallelism (among other advantageous properties) can be exploited to yield computationally efficient implementations. Extension of direct transcription to co-design gives rise to new problem structures and new challenges. Here, we illustrate direct transcription for co-design using a new automotive active suspension design example developed specifically for testing co-design methods. This example builds on prior active suspension problems by incorporating a more realistic physical design component that includes independent design variables and a broad set of physical design constraints, while maintaining linearity of the associated differential equations. A simultaneous co-design approach was implemented using direct transcription, and numerical results were compared with conventional sequential optimization. The simultaneous optimization approach achieves better performance than sequential design across a range of design studies. The dynamics of the active system were analyzed with varied level of control authority to investigate how dynamic systems should be designed differently when active control is introduced

Design and Preliminary Results of a Fuel Flexible Industrial Gas Turbine Combustor A. S. Novick

The work described in this paper is a part of the DOE/ LeRc "Advanced Conversion Technology Project" (AC