Annihilator Banach ∗-algebras and the Peter-Weyl theorem

The QUO VADIS (the effects of QUinapril On Vascular Ace and Determinants of ISchemia) study was a randomized, double-blind, placebo-controlled trial designed to evaluate the effects of long-term angiotensin-converting enzyme (ACE) inhibition on angiotensin II formation in human vasculature. Patients (n <187) scheduled for coronary artery bypass surgery used study medication 27 +/- 1 days before surgery. Segments of internal mammary arteries were exposed to increasing doses (0.1 nM-1 mu M) of angiotensin I and II in organ baths. The rate of local angiotensin II formation is a function of the reciprocal of the difference between the pEC(50)'s of the dose response curves to angiotensin I and II (-log/mol) and of the area between the curves (units). Quinapril (40 mg) and captopril (3x50 mg) similarly and significantly reduced mean blood pressure compared with placebo (p = 0.04). Difference between pEC(50)'s was 0.90 +/- 0.08 in quinapril patients compared with 0.60 +/- 0.08 for placebo (p <5 0.01); the area between curves was 91 +/- 8 for quinapril patients compared with 67 +/- 8 for placebo (p = 0.03). Angiotensin II formation was decreased to a lesser extent with captopril and was not statistically different from placebo (p = 0.3); the difference between pEC(50)'s was 0.83 +/- 0.15; the area between curves was 84 +/- 12. This is the first randomized study to demonstrate that long-term oral treatment with an ACE inhibitor reduces vascular angiotensin II formation in humans

Efficient Testing of High Performance Transaction Processing Systems

Testing the reliability of high performance transaction processing systems poses many difficult challenges that are not adequately answered by conventional testing techniques. We discuss a new test paradigm, which is dynamic and exploratory in nature, and discuss its ability to meet these challenges. We describe an implementation of this paradigm in products that aid in efficiently testing reliable, high performance transaction processing systems at Tandem Computers Inc. 1 Introduction Mission critical database applications, e.g., a stock market system, insist on guaranteed data integrity in all situations. They also demand extremely high performance and high system availability (the cost of even short outages, of the order of minutes, is prohibitively high). Such applications employ high performance transaction processing systems that also have high availability characteristics ([TDG87], [SKPO88], [MHLPS92]). Tandem&apos;s NonStop SQL ([TDG87], [TPG88], [BP88]) is one such syst..

Efficient Testing of High Performance Transaction Processing Systems

Testing the reliability of high performance tlansaetion processing systams poses many difficult challenges that are not adequately answered by conventional testing techniques. We discuss a new test paradigm, which is dy-namic and exploratory in nature, and discuss its ability to meet these challenges. We de-scribe an implementation of thii paradigm in products that aid in efficiently testing reliable, high performance transaction processing sys-tems at T~adem Computers Inc.