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[en] After a short discussion of high field electroluminescence the manufacture of a.c. driven Zns:Mn thin film devices is described. The two insulating layers consist of sputtered Al2O3, the encapsulated active layer is obtained by evaporation in vacuo - during this process the water vapor partial pressure should be kept as low as possible. The voltage-brightness relation makes these devices suitable for multiplexing. The maximum luminance that can be achieved and the luminous efficiency are 3000 cd/m2 and 0.5 lm/W respectively. Improvements still have to be made as far as the long time stability of the displays is concerned. (orig.)
Journal
Siemens Forschungs- und Entwicklungsberichte; ISSN 0370-9736; 
; v. 9(6); p. 358-362
; v. 9(6); p. 358-362
[en] Efflux of CO2 and water vapor from soils influence the isotopic composition of above ground air. Prolonged hot and dry weather conditions can cause significant changes in soil air and soil water 13C and 18O isotope ratios. After a period of hot and dry weather in summer 2003 soil samples showed an increase of up to 0.5% on(delta)18O of soil water in all sampled depths (0-12cm), and at the same time (delta)13C of soil air CO2 rose by 0.4% with an up to four-fold decrease of soil CO2 concentration. These effects are thought to be caused by alteration of the soil structure and changes in microbial activity due to dryness. (author)
Source
Wokaun, A.; Daum, C. (eds.); Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); 194 p; Mar 2004; p. 141; ISSN 1423-7342; ; Available from OSTI; Commercial reproduction prohibited; OSTI as DE20543391; PURL: https://www.osti.gov/servlets/purl/20543391-Cv6p5g/native/
; Available from OSTI; Commercial reproduction prohibited; OSTI as DE20543391; PURL: https://www.osti.gov/servlets/purl/20543391-Cv6p5g/native/
[en] Purpose: To evaluate the various reconstruction methods of helical-CT angiography for the assessment of hemodynamically relevant renal artery stenoses in comparison to i.a. DSA. Methods: In 76 renal arteries the reconstruction modalities AXIAL, MRP, MIP and SSD of helical-CT angiography were compared with the results of i.a. DSA for the determination of the grade and location of the stenosis. Results: The highest accuracy of stenosis grading was 76% with AXIAL reconstruction. In 8% of the cases grading of the stenosis was not evaluable by the AXIAL reconstruction. In these cases, a higher sensitivity in the detection of hemodynamically relevant stenoses (>grade II, >50%) was achieved with the reconstruction mode MPR (96%) than with MIP (92%). In 51% of the cases the reconstruction mode SSD was not suitable for any diagnosis of renal artery stenosis because of overlying calcified plaques. Conclusions: The evidence of hemodynamically relevant stenosis in helical-CT angiography in comparison to i.a. DSA succeeds most reliably by using the reconstruction modality AXIAL in combination with MRP. The MIP reconstruction provides information about the anatomy of the renal arteries within one image. (orig.)
[de]
Ziel: Evaluierung der verschiedenen Rekonstruktionsverfahren der Spiral-CT-Angiographie zur Beurteilung haemodynamisch relevanter Nierenarterienstenosen im Vergleich zur i.a. DSA. Patienten und Methode: Die Rekonstruktionsmodalitaeten AXIAL, MPR, MIP und SSD der Spiral-CT-Angiographie von 76 Nierenarterien wurden unter Bestimmung von Stenosegrad und -lokalisation mit den Ergebnissen der i.a. DSA verglichen. Ergebnisse: Hinsichtlich der Stenosegraduierung bot die AXIALE Rekonstruktion im Vergleich zur i.a. DSA mit 76% der Faelle die groesste Korrelation. 8% der Nierenarterien waren mit ihr alleine nicht beurteilbar. In diesen Faellen wurde durch die zusaetzliche Stenosegradbestimmung mittels der Rekonstruktionsmodalitaet MPR eine hoehere Sensitivitaet (96%) in der Detektion von haemodynamisch relevanten Stenosen (>Grad II, >50%) erreicht als mit der MIP (92%). Der Rekonstruktionsmodus SSD liess in 51% der Faelle aufgrund ueberlagernder Kalkplaques keine Nierenarteriendiagnostik zu. Schlussfolgerung: Der Nachweis haemodynamisch relevanter Nierenarterienstenosen gelingt in der Spiral-CT-Angiographie im Vergleich zur i.a. DSA am zuverlaessigsten unter Anwendung der Rekonstruktionsmodalitaeten AXIAL in Kombination mit MPR, waehrend die MIP-Rekonstruktion in einem Bild ueber Gefaessanzahl und -verlauf der Nierenarterien informiert. (orig.)Journal
RoeFo - Fortschritte auf dem Gebiete der Roentgenstrahlen und der neuen bildgebenden Verfahren; ISSN 0936-6652; ; CODEN RFGNDO; v. 172(2); p. 161-167
; CODEN RFGNDO; v. 172(2); p. 161-167
[en] Published in summary form only
Journal
Verhandlungen der Deutschen Physikalischen Gesellschaft; ISSN 0420-0195; ; CODEN VDPEA; v. 27(1); p. 228
; CODEN VDPEA; v. 27(1); p. 228
[en] Published in summary form only
Journal
Verhandlungen der Deutschen Physikalischen Gesellschaft; ISSN 0420-0195; ; CODEN VDPEA; v. 25(5); p. 1589
; CODEN VDPEA; v. 25(5); p. 1589
[en] Published in summary form only
Journal
Verhandlungen der Deutschen Physikalischen Gesellschaft; ISSN 0420-0195; ; CODEN VDPEA; v. 27(1); p. 147
; CODEN VDPEA; v. 27(1); p. 147
[en] Published in summary form only
Journal
Verhandlungen der Deutschen Physikalischen Gesellschaft; ISSN 0420-0195; ; CODEN VDPEA; v. 27(1); p. 147
; CODEN VDPEA; v. 27(1); p. 147
[en] Dynamic contrast enhanced magnetic resonance imaging is a promising method for quantitative analysis of tumor perfusion and is increasingly used in study of cancer in small animal models. In those studies the determination of the arterial input function (AIF) of the target tissue can be the first step. Series of short-axis images of the heart were acquired during administration of a bolus of Gd-DTPA using saturation-recovery gradient echo pulse sequences. The AIF was determined from the changes of the signal intensity in the left ventricle. The native T1 relaxation times and AIF were determined for 11 mice. An average value of (1.16 ± 0.09) s for the native T1 relaxation time was measured. However, the AIF showed significant inter animal variability, as previously observed by other authors. The inter-animal variability shows, that a direct measurement of the AIF is reasonable to avoid significant errors. The proposed method for determination of the AIF proved to be reliable. (orig.)
Journal
Zeitschrift fuer Medizinische Physik; ISSN 0939-3889; ; v. 18(2); p. 85-90
; v. 18(2); p. 85-90
[en] Total cross sections for the H(π+,π+π+)n reaction have been measured at pion kinetic energies of 180, 184, 190 and 200 MeV. The threshold value for the matrix element a(π+π+) and the s-wave, isospin-2, ππ scattering length a20 were determined. The results were found to be in agreement with chiral perturbation theory and inconsistent with the model of dominance by quark loop anomalies
Journal
[en] Published in summary form only
Journal
Verhandlungen der Deutschen Physikalischen Gesellschaft; ISSN 0420-0195; ; CODEN VDPEA; v. 27(1); p. 207
; CODEN VDPEA; v. 27(1); p. 207
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