springer us jun 1989 (3 Ergebnisse)

Buch. Zustand: Neu. Neuware - The goal of the research out of which this monograph grew, was to make annealing as much as possible a general purpose optimization routine. At first glance this may seem a straight-forward task, for the formulation of its concept suggests applicability to any combinatorial optimization problem. All that is needed to run annealing on such a problem is a unique representation for each configuration, a procedure for measuring its quality, and a neighbor relation. Much more is needed however for obtaining acceptable results consistently in a reasonably short time. It is even doubtful whether the problem can be formulated such that annealing becomes an adequate approach for all instances of an optimization problem. Questions such as what is the best formulation for a given instance, and how should the process be controlled, have to be answered. Although much progress has been made in the years after the introduction of the concept into the field of combinatorial optimization in 1981, some important questions still do not have a definitive answer. In this book the reader will find the foundations of annealing in a self-contained and consistent presentation. Although the physical analogue from which the con cept emanated is mentioned in the first chapter, all theory is developed within the framework of markov chains. To achieve a high degree of instance independence adaptive strategies are introduced.

Buch. Zustand: Neu. Neuware - The Symposium on New Drugs provides a forum for academic investigators, research and development personnel from the pharmaceutical industry and members of the Food and Drug Administration to discuss important clinical research issues. The Ninth Annual symposium on New Drugs addressed the problem of determining the risk versus benefit for use of three important classes of cardiovascular agents: thrombolytic, antiarrhythmic, and hypolipidemic agents. The use of thrombolytic agents has become one of the major advances in clinical intensive cardiologic care in the 1980s. While the lysis of clot(s) obstructing a major coronary artery should reverse or prevent the damage of acute myocardial ischemia and infarction, one must carefully consider the potential risks of such agents in regards to their potential benefits. The time when a thrombolytic agent should be administered to maximize benefit as well as how one defines a dose response relationship using intravenous critical care medicines were discussed as important clinical trial issues. The benefit versus risk data on currently available thrombolytic agents was reviewed and the potential roles for adjunctive agents addressed. Overall strategies regarding post- x thrombolytic care and relationships to sudden cardiac death were also detailed. The panel discussion sections provided a comprehensive view of the current thinking of the various participating groups in this symposium. Sudden cardiac death remains the number one cause of mortality in western industrialized societies.

Buch. Zustand: Neu. Neuware - When the external Quinton-Scribner arteriovenous shunt was developed in 1960, and, a little later, the internal Brescia-Cimino arteriovenous fistula was developed as a vascular access for hemodialysis, thereby making possible regular dialysis therapy of chronic uremic patients, many nephrologists became surgeons, having learned the type of vascular surgery related to hemodialysis quite well. The same series of events occurred with regards to peritoneal dialysis with the introduction of the Tenckhoff catheter and the need for gaining a permanent access to the peritoneum for chronic ambulatory peritoneal dialysis (CAPD) therapy. With time, however, problems relating to vascular and peritoneal access have forced many nephrologists to give up their surgery; meanwhile, many surgeons have become quite expert in some sophisticated techniques relating to dial ysis (e. g., vessel grafting, prosthesis implantation, etc.). Today, whether or not involved in this type of surgery, both nephrologists and surgeons remain interested in knowing all available access devices for dialysis as well as the surgical techniques involved. However, all nephrologists involved in dialysis must know how to prevent or treat complications related to dialysis access. Thus, it appeared to me to be quite advisable to have a book in my series, Topics in Renal Medicine, dealing with vascular and peritoneal access for dialysis.