| 1. |
- Johan, Zdenek, et al.
(författare)
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A Data Parallel Finite Element Method for Computational Fluid Dynamics on the Connection Machine Systems
- 1992
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Ingår i: Computer Methods in Applied Mechanics and Engineering. - : Elsevier BV. - 0045-7825 .- 1879-2138. ; 99:1, s. 113-134
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Tidskriftsartikel (refereegranskat)abstract
- A finite element method for computational fluid dynamics has been implemented on the Connection Machine systems CM-2 and CM-200. An implicit iterative solution strategy, based on the pre-conditioned matrix-free GMRES algorithm, is employed. Parallel data structures built on both nodal and elemental sets are used to achieve maximum parallelization. Communication primitives provided through the Connection Machine Scientific Software Library substantially improved the overall performance of the program. Computations of three-dimensional compressible flows using unstructured meshes having close to one million elements, such as a complete airplane, demonstrate that the Connection Machine systems are suitable for these applications. Performance comparisons are also carried out with the vector computers Cray Y-MP and Convex C-1.
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| 2. |
- Ljungqvist, Olle, 1954-, et al.
(författare)
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Glucose infusion instead of preoperative fasting reduces postoperative insulin resistance
- 1994
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Ingår i: Journal of the American College of Surgeons. - 1072-7515 .- 1879-1190. ; , s. 329-336
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Tidskriftsartikel (refereegranskat)abstract
- In severe catabolic states, such as burn injury, sepsis and accidental injury, a state of marked insulin resistance is encountered. Insulin resistance is also present after elective surgical treatment, more pronounced with increasingly greater magnitude of operation performed. Results of recent animal experiments have shown that even short periods of food deprivation, reducing carbohydrate reserves, alter responses to stress. This notion resulted in our questioning the rationale of carbohydrate depletion associated with overnight preoperative fasting. Twelve patients undergoing elective open cholecystectomy were randomly given no infusion (control group) or 5 milligrams per kilogram per minute of glucose infusion (glucose group) during preoperative overnight fasting. Insulin sensitivity (M value, milligram per kilogram per minute) was determined using the hyperinsulinemic normoglycemic clamp (plasma insulin level, 65 microunits per milliliter and blood glucose level, 4.5 millimoles per liter) before and the first postoperative day. Preoperative insulin sensitivity was similar in the two groups. Postoperatively, M values decreased by 55±3 percent (control group) and by 32±5 percent (glucose group) (p<0.01). Plasma levels of insulin, c- peptide, glucagon, growth hormone, catecholamines and cortisol in connection with clamps were similar in both groups preoperatively and postoperatively. The present results indicate that active preoperative carbohydrate preservation may improve postoperative metabolism because postoperative occurrence of insulin resistance was reduced with preoperative glucose infusion.
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