Search Results - (Author, Cooperation:S. Stolz)

2018-08-24

The American Society for Pharmacology and Experimental Therapeutics (ASPET)

0026-895X

1521-0111

Chemistry and Pharmacology

Medicine

2018-12-04

The Society of Nuclear Medicine (SNM)

0022-3123

Medicine

2011-11-05

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Iris/anatomy & histology/cytology/*metabolism/*radiation effects ; Light Signal Transduction/physiology/*radiation effects ; Mammals/*physiology ; Mice ; Phospholipase C beta/metabolism ; Photic Stimulation ; Primates/physiology ; Reflex, Pupillary/physiology/radiation effects ; Retina/cytology/*metabolism/*radiation effects ; Retinal Ganglion Cells/metabolism/radiation effects ; Rod Opsins/*metabolism

1089-7666

AIP Digital Archive

Physics

An alternative approach to large-eddy simulation based on approximate deconvolution (ADM) is developed. The main ingredient is an approximation of the nonfiltered field by truncated series expansion of the inverse filter operator. A posteriori tests for decaying compressible isotropic turbulence show excellent agreement with direct numerical simulation. The computational overhead of ADM is similar to that of a scale-similarity model and considerably less than for dynamic models. © 1999 American Institute of Physics.

Electronic Resource

1089-7666

AIP Digital Archive

Physics

A formulation of the approximate deconvolution model (ADM) for the large-eddy simulation (LES) of compressible flows in complex geometries is detailed. The model is applied to supersonic compression ramp flow where shock-turbulence interaction occurs. With the ADM approach an approximation to the unfiltered solution is obtained from the filtered solution by a series expansion involving repeated filtering. Given a sufficiently good approximation of the unfiltered solution at a time instant, the flux terms of the underlying filtered transport equations can be computed directly, avoiding the need to explicitly compute subgrid-scale closures. The effect of nonrepresented scales is modeled by a relaxation regularization involving a secondary filter operation and a dynamically estimated relaxation parameter. Results of the large-eddy simulation of the turbulent supersonic boundary layer along a compression ramp compare well with filtered DNS data. The filtered shock solution is correctly predicted by the ADM procedure, demonstrating that turbulent and nonturbulent subgrid-scales are properly modeled. We found that a computationally expensive shock-capturing technique was not necessary for stable integration. As a consequence, the computational effort for simulations with ADM is approximately as large as for a coarse-grid DNS with a hybrid compact-upwind-ENO scheme, since the additional computational cost for the subgrid-scale model is more than compensated due to the fact that in the LES flux-derivatives can be computed by linear central finite differences on the entire domain. © 2001 American Institute of Physics.

Electronic Resource

1089-7666

AIP Digital Archive

Physics

The approximate deconvolution model (ADM) for the large-eddy simulation of incompressible flows is detailed and applied to turbulent channel flow. With this approach an approximation of the unfiltered solution is obtained by repeated filtering. Given a good approximation of the unfiltered solution, the nonlinear terms of the filtered Navier–Stokes equations can be computed directly. The effect of nonrepresented scales is modeled by a relaxation regularization involving a secondary filter operation. Large-eddy simulations are performed for incompressible channel flow at Reynolds numbers based on the friction velocity and the channel half-width of Reτ=180 and Reτ=590. Both simulations compare well with direct numerical simulation (DNS) data and show a significant improvement over results obtained with classical subgrid scale models such as the standard or the dynamic Smagorinsky model. The computational cost of ADM is lower than that of dynamic models or the velocity estimation model. © 2001 American Institute of Physics.

Electronic Resource

0093-061X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Political Science

Electronic Resource

1432-1459

Huntington's disease ; Sleep EEG ; Basal ganglia disorders

Springer Online Journal Archives 1860-2000

Medicine

Summary Nocturnal sleep was studied in 16 inpatients with Huntington's disease. In comparison with healthy controls, patients exhibited a disturbed sleep pattern with increased sleep onset latency, reduced sleep efficiency, frequent nocturnal awakenings, more time spent awake and less slow wave sleep. These abnormalities correlated in part with duration of illness, severity of clinical symptoms, and degree of atrophy of the caudate nucleus. Patients showed an increased density of sleep spindles.

Electronic Resource

1434-3916

Springer Online Journal Archives 1860-2000

Medicine

Zusammenfassung Im vorliegenden Falle eines extraskeletalen Osteosarkoms traten Schwierigkeiten auf bei der Diagnosestellung a) eines malignen mesenchymalen Tumors und b) eines knochenbildenden Tumors. Nur fokal waren die lehrbuchmäßigen Kriterien eines Osteosarkoms nachweisbar. Differentialdiagnostisch sind vor allem pseudosarkomatöse knochenbildende Tumoren abzugrenzen, die histologisch malignitätsverdächtig erscheinen können, jedoch einen gutartigen klinischen Verlauf aufweisen.

Summary In this case of an extraskeletal osteosarcoma initially there were typical difficulties in diagnosing a) a malignant mesenchymal tumor and b) a bone-producing tumor. Only focally the text-booking findings of an osteosarcoma were present. The differential diagnosis concerned mainly pseudosarcomatous lesions with bone formations, which histologically may appear suspicious, however, follow a benign course clinically.

Electronic Resource