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7. High-resolution grazing-incidence x-ray diffraction for characterization of defects in crystal surface layers

Author

Kondrashkina, E.A., Stepanov, S.A., Schmidbauer, M., Opitz, R., Kohler, R., and Rhan, H.

Subjects
X-ray diffractometer -- Usage, Crystals -- Structure, Superlattices as materials -- Research, Physics
Abstract

The unusual aspects of high-resolution measurements in grazing-incidence diffraction (GID) were examined, both theoretically and experimentally. Findings indicated that complete discrimination between coherent reflection and diffuse scattering due to defects in GID needs a three-dimensional mapping of reciprocal space. These measurements can be made utilizing a combination of analyzer crystal and position-sensitive detector for angular analysis of scattered x-rays in mutually perpendicular planes.

Published
1997

8. Dietary calcium chloride vs. calcium carbonate reduces urinary pH and phosphorus concentration, improves bone mineralization and depresses kidney calcium level in cats

Author

Pastoor, F.J.H., Opitz, R., van T' Klooster, A. Th., and Beynen, A.C.

Subjects
Calcium, Dietary -- Research, Calcium chloride -- Health aspects, Calcium in animal nutrition -- Research, Calcium carbonate -- Health aspects, Cats -- Food and nutrition, Food/cooking/nutrition
Abstract

The effect of dietary calcium chloride vs. calcium carbonate on mineral metabolism was studied in cats. Ovariectomized cats and female kittens were fed purified diets with a normal calcium level (9.5 mmol Ca/MJ) but containing either calcium carbonate or calcium chloride, or were fed diets with a high calcium level (17.7 mmol Ca/MJ) containing either calcium carbonate alone or equimolar amounts of both calcium carbonate and calcium chloride. A 4 X 4-wk cross-over study using adult cats and a 31-wk parallel study using kittens were conducted. Calcium, phosphorus and magnesium balances were established regularly. In the course of the experiment with the kittens, blood samples were taken and X-ray photographs of the tibiae made. At the age of 39 wk, the kittens were killed, and organs and bones were collected. In both adult cats and kittens fed the high calcium diets, urinary concentrations of magnesium and phosphorus and apparent absorption of these minerals were lower than after feeding the normal calcium diets. Urinary pH and phosphorus concentration were lower in cats and kittens fed diets with calcium chloride instead of calcium carbonate. Body weight gain and tibia growth in the kittens tended to be greater after feeding the diets with calcium chloride. Calcium chloride vs. calcium carbonate and also supplemental calcium chloride in the high calcium diet significantly stimulated femur density and reduced renal calcium concentration. INDEXING KEY WORDS: mineral excretion; bone mineralization; calcium chloride; nephrocalcinosis; cats

Published
1994

10. Paleodata for and from archaeology

Author

Kohler, Timothy A., Buckland, Philip I., Kintigh, K. W., Bocinsky, R. K., Brin, A., Gillreath-Brown, A., Ludäscher, B., McPhillips, T. M., Opitz, R., Terstriep, J., Kohler, Timothy A., Buckland, Philip I., Kintigh, K. W., Bocinsky, R. K., Brin, A., Gillreath-Brown, A., Ludäscher, B., McPhillips, T. M., Opitz, R., and Terstriep, J.

Abstract

Archaeology depends on, and generates, proxy paleoclimatic and paleoenvironmental data. We review various initiatives, most quite recent, by which archaeologists seek to make these data more readily discoverable and useful, to facilitate the cumulation of research., Theme issue on BUILDING AND HARNESSING OPEN PALEODATA.EDITORS: John W. Williams, Alicia J. Newton, Darrell S. Kaufman and Lucien von Gunten, VISEAD, SEAD

Published
2018
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11. Measuring usewear on black gloss pottery from Rome through 3D surface analysis

Author

Banducci, L. (Laura), Opitz, R. (Rachel), Mogetta, M. (Marcello), Banducci, L. (Laura), Opitz, R. (Rachel), and Mogetta, M. (Marcello)

Abstract

This project involves the high-resolution 3D laser scanning of a cache of Italian black gloss pottery from the Capitoline Museums in Rome. Our aim is to examine in detail the minute traces of production and use of these vessels and to produce a digital record of their form. We have experimented with several scanning devices in order to determine the optimal methods for capturing abrasions on pottery and are developing digital methods for surface analysis. The purpose of the analysis is to consider how black gloss vessels from ritual contexts (tomb and sanctuary deposits) may have been used before they were deposited and to refine our understanding of vessel production methods.

Published
2018
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13. Paleodata for and from archaeology

Author

Kohler, Timothy A, primary, Buckland, PI, additional, Kintigh, KW, additional, Bocinsky, RK, additional, Brin, A, additional, Gillreath-Brown, A, additional, Ludäscher, B, additional, McPhillips, TM, additional, Opitz, R, additional, and Terstriep, J, additional

Published
2018
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18. Chantier «Construction Historique des Espaces Forestiers»

Author

Nuninger, Laure, Fruchart, Catherine, Laplaige, Clément, Bas, C., Bépoix, S., Bossuet, G., Chenal, T., Crozet, A., Daval, D., Dupin, A., Fovet, E., Georges-Leroy, M., Girardclos, O., Grosbois, J.-P., Josseron, J.-P., Nouvel, P., Opitz, R., Rossi, A., Ruffaldi, P., Thivet, M., Zimmer, C., Laplaige, Clément, Maison des Sciences de l'Homme et de l'Environnement Claude Nicolas Ledoux (MSHE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Cités, Territoires, Environnement et Sociétés (CITERES), Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT), Archéologie, Terre, Histoire, Sociétés [Dijon] (ARTeHiS), Ministère de la Culture et de la Communication (MCC)-Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Ministère de la Culture et de la Communication (MCC), Office National des Forêts (ONF), Archaeology, School of Humanities, University of Glasgow, usr 3124 MSHE C.-N. Ledoux, FEDER ODIT, Centre National de la Recherche Scientifique (CNRS)-Université de Tours, Maison des Sciences de l'Homme et de l'Environnement Claude Nicolas Ledoux (UAR 3124) (MSHE), Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SHS.ARCHEO] Humanities and Social Sciences/Archaeology and Prehistory, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SHS.HIST] Humanities and Social Sciences/History, [SHS.HIST]Humanities and Social Sciences/History
Abstract

Chapitre dans le rapport final du FEDER ODIT

Published
2015

31. Estimation of Shear Stress-related Blood Damage in Heart Valve Prostheses - in Vitro Comparison of 25 Aortic Valves

Author

Helmut Reul, Wurzinger Lj, Opitz R, and Giersiepen M

Subjects
Blood Platelets, Aortic valve, Erythrocytes, 030232 urology & nephrology, Biomedical Engineering, Medicine (miscellaneous), Hemodynamics, Bioengineering, 030204 cardiovascular system & hematology, Hemolysis, Biomaterials, Hemoglobins, 03 medical and health sciences, 0302 clinical medicine, medicine, Shear stress, Humans, Heart valve, L-Lactate Dehydrogenase, Models, Cardiovascular, General Medicine, medicine.disease, medicine.anatomical_structure, Shear (geology), Aortic Valve, Heart Valve Prosthesis, Blood damage, Circulatory system, Stress, Mechanical, Blood Flow Velocity, Mathematics, Biomedical engineering
Abstract

The hemodynamics of heart valve prostheses can be reproducibly investigated in vitro within circulatory mock loops. By measuring the downstream velocity and shear stress fields the shear stresses which are clinically responsible for damage to platelets and red blood cells can be determined. The mechanisms of damage and the effects of shear stresses on blood corpuscles were investigated by Wurzinger et al. (3, 4) at the Aerodynamics Institute of the RWTH Aachen. In the present study, the above data are incorporated into a mathematical correlation, which serves as a basic model for the estimation of blood damage. This mathematical model was applied to in vitro investigations of 25 different aortic valve prostheses. The results were compared to clinical findings. In most cases agreement was good, indicating that this model may be directly applied to the clinical situation. This new method facilitates the estimation of clinically expected blood damage from in vitro measurements. It may be useful for the development and evaluation of new valve prostheses. By comparative evaluation of different valve types it also provides additional information to help the implanting surgeon select the optimum valve for his patient.

Published
1990

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