591 research outputs found
Non-solvable contractions of semisimple Lie algebras in low dimension
The problem of non-solvable contractions of Lie algebras is analyzed. By
means of a stability theorem, the problem is shown to be deeply related to the
embeddings among semisimple Lie algebras and the resulting branching rules for
representations. With this procedure, we determine all deformations of
indecomposable Lie algebras having a nontrivial Levi decomposition onto
semisimple Lie algebras of dimension , and obtain the non-solvable
contractions of the latter class of algebras.Comment: 21 pages. 2 Tables, 2 figure
Living renal donors: optimizing the imaging strategy--decision- and cost-effectiveness analysis
PURPOSE: To determine the most cost-effective strategy for preoperative
imaging performed in potential living renal donors. MATERIALS AND METHODS:
In a decision-analytic model, the societal cost-effectiveness of digital
subtraction angiography (DSA), gadolinium-enhanced magnetic resonance (MR)
angiography, contrast material-enhanced spiral computed tomographic (CT)
angiography, and combinations of these imaging techniques was evaluated.
Outcome measures included lifetime cost, quality-adjusted life-years
(QALYs), and incremental cost-effectiveness ratios. A base-case analysis
was performed with a 40-year-old female donor and a 40-year-old female
recipient. RESULTS: For the donor, MR angiography (24.05 QALYs and 9,000
dollars) dominated all strategies except for MR angiography with CT
angiography, which had an incremental ratio of 245,000 dollars per QALY.
For the recipient, DSA and DSA with MR angiography yielded similar results
(10.46 QALYs and 179,000 dollars) and dominated all other strategies. When
results for donor and recipient were combined, DSA dominated all other
strategies (34.51 QALYs and 188,000 dollars). If DSA was associated with a
99% specificity or less for detection of renal disease, MR angiography
with CT angiography was superior (34.47 QALYs and 190,000 dollars).
CONCLUSION: For preoperative imaging in a potential renal donor, DSA is
the most cost-effective strategy if it has a specificity greater than 99%
for detection of renal disease; otherwise, MR angiography with CT
angiography is the most cost-effective strategy
Renewable Energy Opportunities at Fort Sill, Oklahoma
This document provides an overview of renewable resource potential at Fort Sill, based primarily upon analysis of secondary data sources supplemented with limited on-site evaluations. This effort focuses on grid-connected generation of electricity from renewable energy sources and on ground source heat pumps for heating and cooling buildings. The effort was funded by the U.S. Army Installation Management Command (IMCOM) as follow-on to the 2005 Department of Defense (DoD) Renewables Assessment. The site visit to Fort Sill took place on June 10, 2010
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