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1. Ferroelectric polycrystals: structural and microstructural levers for property-engineering via domain-wall dynamics

Author

J. Schultheiß, G. Picht, J. Wang, Y.A. Genenko, L.Q. Chen, J.E. Daniels, and J. Koruza

Subjects
General Materials Science, ddc:530
Abstract

Ferroelectrics have a spontaneous electrical polarization that is arranged into domains and can be reversed by an externally applied field. This high versatility makes them useful in enabling components such as capacitors, sensors, and actuators. Key parameters to tune their dielectric, piezoelectric, and electromechanical performance are the domain structure and the dynamic of the domain walls. In fixed compositions, this is often realized by chemical doping. In addition, structural and microstructural parameters, such as grain size, degree of crystallographic texture or porosity play a key role. An important step forward in the field was the fundamental understanding of the link between the local electric and mechanical driving forces and domain wall motion. Here, the impact of structure and microstructure on these driving forces is reviewed and an engineering toolbox is introduced. An overview of advances in the understanding of domain wall motion on the micro- and nanoscale is provided and discussed in terms of the macroscopic functional performance of polycrystalline ferroelectrics/ferroelastics. In addition, a link to theoretical and computational models is established. The review concludes with a discussion about beyond state-of-the-art characterization techniques, new approaches, and future directions toward non-conventionally ordered ferroelectrics for next-generation nanoelectronic and energy-storage applications.

Published
2023

2. Control of δ-γ Transformation during Solidification of Stainless Steel Slabs in the Mould

Author

G. Picht, Antonio Spaccarotella, M. R. Ridolfi, and Piotr R. Scheller

Subjects
Materials science, Ferrous metallurgy, Alloy, Metallurgy, Metals and Alloys, Defect free, engineering.material, Condensed Matter Physics, Cooling rate, Ferrite (iron), Materials Chemistry, engineering, Slab, Physical and Theoretical Chemistry
Abstract

In order to obtain satisfactory workability properties required for defect free slab and strip production, the parameters of the casting process, e.g. cooling rate at the initial solidification for the alloy in question must, on the one hand, be carefully adjusted. On the other hand, controlling the characteristics of the solidification structure by chemical composition then takes on particular significance. The main aims of the work were to find out the influence of the phase transformation δ-γ during the initial solidification of different variants of AISI 304 slabs cast in the industrial process on the ferrite distribution on slab surface, and how this relationship could favour the improvements of the surface slab quality.This report contains the joint contributions of the collaborative ECSC project among Centro Sviluppo Materiali (CSM), Krupp Thyssen Nirosta (KTN) and the Department of Ferrous Metallurgy of Rheinisch Westfalische Technische Hochschule Aachen (RWTH).

Published
2003

3. Nachbetreuung von Trabekulektomien

Author

Franz Grehn, G. Picht, and Y. Mutsch

Subjects
Gynecology, Ophthalmology, medicine.medical_specialty, business.industry, Medicine, business
Abstract

Fragestellung. Die intensive Nachbetreuung nach Glaukomoperation ist unerlasslich fur einen langfristigen Erfolg. Hierbei mussen postoperative Komplikationen erkannt und adaquat behandelt werden. Patienten und Methoden. Im Rahmen einer retrospektiven Studie wurden 113 Augen von 113 konsekutiven Patienten nach Trabekulektomie bezuglich postoperativer Komplikationen und therapeutischer Konsequenzen ausgewertet. Der Nachbeobachtungszeitraum betrug 6 Monate. Als Erfolgskriterium wurde ein intraokularer Druck (IOD) 20% im Vergleich zum praoperativen behandelten IOD definiert. Ergebnisse. Die meisten Komplikationen traten innerhalb der ersten 3 Wochen auf: beginnende Sickerkissenvernarbung (47,6%), Aderhautamotio (18,6%), Vorderkammerabflachung (8%), Fibrinreaktion (5,3%), Uberfiltration (4,4%), verminderter Abflus unter dem Skleradeckel (4,4%), Hornhautdelle (3,5%), Irisprolaps (3,5%), ausere Fistulation (2,7%), Steroideffekt (1,8%), Ziliarkorperabhebung (1,8%) und malignes Glaukom (0,9%). Postoperativ benotigten 45,1% der Augen zusatzliche invasive therapeutische Masnahmen (5-Fluorouracil (5-FU)-Injektionen 28,3%, Needling + 5-FU-Injektionen 14,2%, Offnung eines Skleradeckelfaden mit dem Laser 6,2%; Irisreposition, YAG-Laser-Iridotomie, Sickerkissen-Laserkoagulation, Eigenblutinjektion, Zyklokryokoagulation beschrankten sich auf Einzelfalle). 36,3% erhielten konservative therapeutische Masnahmen (z.B. Anderung der Applikationshaufigkeit von Steroiden, intensivierte Zykloplegie). Nach 6 Monaten betrug die Erfolgsquote ohne Anwendung von Glaukommedikamenten 88,5%. Schlussfolgerung. Fruhzeitiges Erkennen postoperativer Komplikationen, insbesondere bei beginnender Sickerkissenvernarbung, ermoglicht rechtzeitige Therapieentscheidungen, die bei etwa der Halfte der Patienten notwendig sind. Dadurch lasst sich eine wesentlich hohere Erfolgsquote erreichen.

Published
2001

5. Erkrankungen des Auges

Author

F. Grehn, W. Lieb, and G. Picht

Abstract

Bereits in fruhester Kindheit pragen visuelle Eindrucke die Entwicklung des Kindes und seine Beziehungen zu Mitmenschen und Umwelt. Das Wunder des Sehens so weit als moglich zu erhalten oder wiederherzustellen stellt eine interdisziplinare Herausforderung an Padiater und Ophthalmologen dar.

Published
2009

6. Supplement II: Abstracts of the international symposium on Skin Carcinogenesis in man and in experimental models. Heidelberg, 29–31 October 1991 (pp S61–S88)

Author

C. J. Kemp, G. Stingl, C. Caulín, E. G. Jung, H. Tanooka, J. Lassus, E. F. Griffin, Douglas R. Lowy, J. L. Jorcano, J. C. Wang, L. Weber, R. Kato, Paul Janiaud, S. Ohno, A. Schwaaf, R. Gollhausen, N. Sönnichsen, H. Hug, Toshio Kuroki, M. Yaar, J. R. Schlehofer, K. Krasagakis, PE Purkis, Monika M. Gross, H. Heine, H. Mukhtar, J. A. Newton, G. Reisbach, C. Bauer, A. Winter, K. M. Niemi, S. Yamamoto, Bernd L. Sorg, V. A. DeLeo, S. Bruvers, P. Navarro, A. Ootsuyama, G. Tadini, Bert J. Vermeer, D. English, A. B. Bianchi, S. Feil, A. Lehmus, H. Winter, P. T. Strickland, C. Proby, J. M. Foidart, R. Eckert, R. E. Albert, N. E. Fusenig, E. Lee, R. D. Granstein, P. Bums, E. Berti, J. Jürgensmeier, H. Roeser, J. Nährig, A. Anders, F. R. de Gruijl, C. S. Baxter, R. Mailhammer, H. van Weelden, Y. Fujiwara, E. Filvaroff, E. Weber, S. Froschermaier, G. Graf, J. C. Barrett, J. Weiss, H. Weber, B. Hennig, M. Miller, F. Urbach, K. Yamamura, E. Pâques, A. Hülsen, Seymour Garte, B. A. Gilchrest, S. Neill, K. Thalmeier, C. Zechel, Jan P. Vandenbroucke, B. Epe, P. Höfler, B. Przybilla, A. Markey, C. Gilles, C. Bauluz, I. B. Weinstein, U. Van der Piepen, Fokko J. Van Der Woude, T. Jimbo, A. Cano, P. Tomakidi, M. Quintanilla, A. Real, T. Grande, G. T. Bowden, H. Friesel, Y. Mishima, Jan N. Bouwes Bavinck, D. Breitkreutz, Stanley J. Miller, M. Piette, E. Wagner, M. Buček, A. Kopp-Schneider, C. A. Afshari, A. Ranki, M. Garmyn, Margaret L. Kripke, C. Baxter, E. Hecker, Hiroshi Tanooka, F. Harks, E. Lopez-Bran, P. A. Futreal, H. Wei, M. B. Abdel-Naser, A. Diugosz, S. Altmeier, J. Macejewski, Uwe Wollina, J. Römisch, B. Eberlein, E. B. Broecker, Y. Funasaka, M. Glover, M. Haas, S. Gruner, T. Bishop, J. Leers, G. Picht, A. Gilani, W. Diezel, D. S. Silvers, A. Glick, R. Krauß, H. Harris, Anne Østerlind, J. Levy, A. Cerri, E. Danen, K. Schiess, E. Viesel, H. Gröger, B. C. Bastian, K. Hayashibe, K. H. Richter, K. Frenkel, Odilia Popanda, M. Gómez, I. Moll, U. Schleenbecker, M. Ueda, Fritz Anders, H. D. Volk, K. Möller, M. Ichihashi, M. Martín, G. Krauter, S. Krüger-Krasagakes, D. J. Ruiter, J. C. van der Leun, M. Götschl, R. Niedner, Sylvia A. Sedman, T. M. Rünqer, Akira Ootsuyama, Judith P. Johnson, A. Montes, A. G. Ushmorov, G. Bauer, R. Schnapke, S. Kahn, B. Kempkes, C. Garbe, B. Steinbauer, B. K. Armstrong, P. Plein, T. Schneider, C. Missero, B. Schlatterer, M. Schara, P. J. Heenan, M. Stephan, B. A. Burkhart, A. J. P. Klein-Szanto, Eva-B. Bröcker, R. Halaban, S. Grabbe, G. N. P. van Muijen, E. Azizi, D. Schaefer, A. A. Hartmann, C. Ballestin, P. Klein-Bauernschmitt, R. Shukla, G. Kelfkens, M. Nelson, Friedrich Rippmann, M. Kaszkin, S. G. Zubova, Bruce D. Cohen, T. Cody, A. Kricker, V. B. Okulov, P. Fuchs, V. Kinzel, S. Osada, A. Balmain, A. B. Stoler, T. T. Sun, J. Svetek, W. D. Lehmann, F. Larcher, P. Krieg, Jürgen Schweizer, M. Hergenhahn, A. Faissner, G. P. Dotto, C. J. Conti, U. Burcin, L. Hültner, V. Bataille, G. Fürstenberger, EB Lane, A. Smith, D. Jahrens, K. Elgjo, Walter Troll, A. Gandarillas, M. Schön, R. D. Owen, S. Ramón y Cajal, Heinz Walter Thielmann, A. O. Danilov, S. H. Yuspa, J. Cuzick, P. L. Randell, Sylvia Unger, J. A. Boyd, C. Sutter, N. M. Navone, IM Leigh, H. J. Stark, L. A. Annab, R. Gitto, James M. Spencer, C. E. Orfanos, R. M. Lavker, W. Tilgen, R. Albert, H. L. Moses, Eric J. Stanbridge, R. Kosters, Rainer Schmidt, P. Boukamp, E. Schöpf, U. Pascheberg, Yuichi Hashimoto, A. Robledo, F. Marks, J. Sherman, J. Richards, C. E. Klein, Frans H.J. Claas, S. Pečar, Bernard M. Mechler, Doris Rueß, B. Fiebich, Lutz Edler, John T. Schiller, and H. Fujiki

Subjects
Oncology, Cancer Research, medicine.medical_specialty, business.industry, Internal medicine, Medicine, General Medicine, business, Carcinogenesis, medicine.disease_cause
Published
1991

8. [Follow-up of trabeculectomy. Complications and therapeutic consequences]

Author

G, Picht, Y, Mutsch, and F, Grehn

Subjects
Adult, Aged, 80 and over, Male, Reoperation, Aftercare, Glaucoma, Trabeculectomy, Middle Aged, Combined Modality Therapy, Cicatrix, Postoperative Complications, Risk Factors, Humans, Female, Aged, Follow-Up Studies
Abstract

Intensive follow-up after trabeculectomy is important for long-term success. In the postoperative period, complications must be detected early in order to initiate adequate therapeutic measures.In a retrospective study 113 eyes from 113 consecutive patients were followed-up for a period of 6 months after trabeculectomy with regard to postoperative complications and therapeutic decisions (invasive and conservative). Criteria of success were defined as an intraocular pressure (IOP)21 mmHg without antiglaucomatous treatment as well as an IOP reduction20% compared to the preoperatively treated IOP.Most of the postoperative complications occurred within the first 3 weeks: scarring of the filtering bleb (47.6%), choroidal detachment (18.6%), shallowing of the anterior chamber (8%), fibrinous reaction (5.3%), overfiltration (4.4%), reduced flow under the scleral flap (4.4%), corneal dellen (3.5%), prolapse of the iris (3.5%), external fistulation (2.7%), increase of the IOP due to steroids (1.8%), detachment of the ciliary body (1.8%) and malignant glaucoma (0.9%). In the postoperative period, 45.1% of the eyes needed further interventions such as 5-fluorouracil (5-FU) injections (28.3%), needling and 5-FU-injections (14.2%), laser suturolysis (6.2%). Repositioning of the iris, YAG-laser iridotomy, laser treatment of the filtering bleb, autologous blood injection and cyclocryoapplication were needed only in rare cases and 36.3% received other conservative treatment (i.e. modification of topical steroids, increase of cycloplegic treatment). After 6 months the success rate without antiglaucoma medication was 88.5%.An intensive follow-up after trabeculectomy is mandatory to avoid postoperative failure. In about half of the patients postoperative additional therapeutic measures became necessary, particularly if scarring of the filtering bleb occurred. Paying attention to these factors yields in a high success rate after filtering surgery.

Published
2001

9. Classification of Developing Filtering Blebs after Trabeculectomy

Author

F. Grehn and G. Picht

Subjects
Intraocular pressure, medicine.medical_specialty, genetic structures, medicine.medical_treatment, Group ii, Connective tissue, Biology, eye diseases, Surgery, Filtering bleb, medicine.anatomical_structure, medicine, Glaucoma surgery, Trabeculectomy, sense organs, Bleb (cell biology), Wound healing
Abstract

The development of the filtering blebs after trabeculectomy of 55 eyes was followed to establish a classification of filtering blebs with a score system. The number of microcysts, the amount of vascularization, the appearance of “corkscrew vessels”, encapsulation, and the height of the filtering bleb were evaluated semi-quantitatively. Two groups were defined: (1) eyes with a spontaneous favorable clinical outcome, and (2) eyes that needed further postoperative interventions (5fluorouracil injections, needling, or revision). In group I, microcysts were frequent, excessive vascularization and the presence of “corkscrew vessels” were rare, encapsulation was infrequent, and the bleb was moderately elevated. In contrast, in group II, microcysts were generally absent, vascularization, “corkscrew vessels” and encapsulation were frequent, and the bleb was usually highly elevated. This behavior parallels the different activities of wound healing of the subconjunctival connective tissue. Observation of the developing filtering bleb after trabeculectomy according to standardized slit-lamp criteria may help to predict the outcome and may provide clues for the necessity of further treatment independent from postoperative intraocular pressure.

Published
2000

10. Wound Healing and Scarring of the Developing Filtering Bleb — A Major Challenge in Glaucoma Surgery

Author

F. Grehn, Elke Lütjen-Drecoll, G. Picht, and U. Welge Lüssen

Subjects
medicine.medical_specialty, business.industry, medicine.medical_treatment, Mitomycin C, Glaucoma, medicine.disease, Surgery, Filtering bleb, Glaucoma surgery, Medicine, Trabeculectomy, Glaucoma filtering surgery, business, Wound healing, Scleral flap
Abstract

Trabeculectomy has become the standard surgical procedure for primary open-angle glaucoma (POAG) during the last few decades. Modifications of the technique and preoperative assessment of risk factors have constantly reduced the rate of acute postoperative complications. The main challenge that remains is, however, the lack of predictability of postoperative wound healing and scar formation at the filtering site [1–3]. The basic mechanisms of wound healing in glaucoma filtering surgery are still poorly understood [4–6]. Antimetabolites such as Mitomycin C and 5-fluorouracil (5FU) are now routinely used to reduce scar formation in high risk cases, but their mechanisms of action are not specific [5, 7–9].

Published
1999

12. Absract

Author

Marietta Kaszkin, Volker Kinzel, Karl Maly, Irina Bichler, Florian Lang, Hans H. Grunicke, R. Pepperkok, R. Jakobi, P. Lorenz, W. Ansorge, W. Pyerin, P. Borowski, M. Harbers, A. Ludwig, T. Kischel, H. Hilz, K. Eckert, A. Granetzny, J. Fischer, R. Grosse, V. Manch, S. Wehner, B. Kornhuber, U. Ebener, K. Müller-Decker, G. Fürstenberger, I. Vogt, F. Marks, G. Graschew, A. Küsel, W. Hull, W. Lorenz, H. W. Thielmann, Gisela H. Degen, Alexius Freyberger, A. Müller, M. Linscheid, Ulrike Hindermeier, Ute Jorritsma, K. Golka, W. Föllmann, H. Peter, H. M. Bolt, S. Monnerjahn, D. N. Phillips, A. Never, A. Seidel, A. R. Glatt, K. Wiench, E. Frei, P. Schroth, M. Wiessler, T. Schäfer, M. Hergenhahn, E. Hecker, D. Proft, P. Bartholmes, R. S. Bagewadikar, B. Bertram, N. Frank, Hanno Leibersperger, Michael Gschwendt, Friedrich Marks, S. Fasco, Peter Plein, Karin Schiess, Lothar Seidler, T. Jacobi, E. Besemfelder, M. Stephan, W. D. Lehmann, M. Grell, B. Thoma, P. Scheurich, Markus Meyer, Hans Grunicke, G. Jaques, B. Wegmann, K. Ravemann, Odilia Popanda, Heinz Walter Thielmann, H. Voss, U. Wirkner, Dieter Werner, D. Strand, A. Kalmes, H. -P. Walther, B. Mechler, S. Volker Schirrmacher, V. Kinzel, R. Hess, H. -G. Hanagarth, C. Hässler, G. Brandner, Christian Ertel, B. Gückel, V. Schirrmacher, B. A. Kyewski, U. Bogdahn, P. Jachimczak, J. Schneider, W. Brysch, W. Schlingensiepen, D. Drenkard, C. Behl, J. Winkler, R. Apfel, J. Meixensberger, K. Stulle, P. Marquardt, H. P. Vollmers, J. Müller, H. -K. Müller-Hermelink, M. Schuermann, G. Seemann, Angelika Ptok, M. Ptok, T. E. Carey, M. Steffen, U. C. Nitz, B. Everding, F. Hölzel, G. Kantwerk-Funke, G. Boll, K. S. Zänker, P. Hölzel, J. Heymanns, C. Hennig, M. Rotsch, K. Havemann, Jürgen R. Fischer, Sabine Stehr, Harald Lahm, Peter Drings, Peter H. Krammer, M. Kirsch, A. Strubel, A. Kist, R. Hinn, H. Fischer, A. Buttler, G. Schackert, S. Friedenauer, D. Lindner, B. Marczynski, H. Karcls, H. W. Goergens, B. Epe, E. Müller, D. Schütze, S. Boiteux, E. Eder, C. Deininger, C. Hoffman, E. Scherer, E. Vermeulen, H. J. van Kranen, J. Bax, R. A. Woutersen, C. F. van Kreijl, B. Schurich, H. Hagedorn, E. Kamp, G. Eisenbrand, B. Spiegelhalder, U. Bolm-Audorff, H. G. Bienfait, R. Preussmann, C. -D. Wacker, H. Kehl, Z. Akkan, J. Ries, M. Meger, S. E. Shephard, D. Gunz, W. K. Lutz, A. R. Tricker, R. Kurnar, M. Siddiqi, P. Mende, B. Pfundstein, A. Scholl, C. Janzowski, D. Jacob, P. Goelzer, I. Henn, H. Zankl, K. -H. Zimlich, Barbara Gansewendt, Ricarda Thier, K. R. Schroeder, E. Hallier, G. Moeckel, W. Heiden, M. Waldherr-Teschner, J. Brickmann, H. Roeser, G. Krauter, G. Scherer, A. Krätschmer, H. Hauenstein, F. Adlkofer, R. C. Fernando, H. H. Schmeiser, W. Nicklas, Wolfgang Pfau, David H. Phillips, S. Scheckenbach, S. Cantoreggi, Monika Leutbecher, H. Ottenwälder, U. Föst, P. M. Baumgart, H. -C. Kliem, S. Data, C. Pfeiffer, A. Fuchs, P. Schmezer, F. Kuchenmeister, B. L. Pool-Zober, U. M. Liegibel, B. L. Pool-Zobel, L. Steeb, H. Friesel, Th. Schneider, H. R. Scherf, A. Buchmann, R. Bauer-Hofmann, J. Mahr, M. Schwarz, R. Schmidt, F. Rippmann, B. Steinbauer, P. Zlfu, B. Bunk, W. Hefter, K. Klinga, M. R. Berger, L. W. Robertson, G. Luebeck, S. Moolgavkar, U. Torsten, M. Kowalczyk-Wagner, H. Weitzel, Ch. Zechel, H. Peters, F. Anders, S. Ambs, T. Kirchner, H. -G. Neumann, C. Einig, E. Eigenbrodt, D. Oesterle, E. Deml, G. Weisse, U. Gerbracht, H. Stumpf, E. Filsingcr, P. Bannasch, W. Muster, P. Cikryt, P. Münzel, E. Röhrdanz, K. W. Bock, H. -P. Lipp, T. Wiesmüller, H. Hagenmaier, D. Schrenk, A. Karger, G. Bauer, P. Höfler, M. Götschl, E. Viesel, J. Jürgensmeier, D. Schaefer, G. Picht, J. Kiefer, P. Krieg, R. Schnapke, S. Feil, E. Wagner, U. Schleenbecker, A. Anders, M. M. Gross, S. Unger, E. J. Stanbridge, Petra Boukamp, Ulrich Pascheberg, Norbert E. Fusenig, H. Abken, U. H. Weidle, F. Grummt, K. Willecke, R. Schäfer, A. Hajnal, I. Balmer, R. Klemenz, P. E. Goretzki, H. Reishaus, M. Demeure, H. Haubruck, J. Lyons, H. D. Röher, Sylvia Trouliaris, Angelika Hadwiger-Fangmeier, Elke Simon, Heiner Niemann, Teruko Tamura, G. Westphal, Elke Turner, H. Karels, M. Blaszkewicz, Helga Stopper, Dietmar Schiffmann, Umberto De Boni, M. Schuler, R. Schnitzler, M. Metzler, E. Pfeiffer, R. Aulenbacher, T. Langhof, K. R. Schröder, K. Saal, H. K. Müller-Hermelink, W. Henn, G. Seitz, P. Lagoda, A. Christmann, N. Blin, C. Welter, D. Adam, D. Fömzler, C. Winkler, W. Mäueler, M. Schartl, B. Theisinger, G. Schüder, U. Rüther, C. Nunnensiek, H. A. G. Müller, W. Rupp, M. Lüthgens, P. Jipp, I. Kinzler, M. Gulich, H. J. Seidel, O. H. Clark, F. McCormick, H. R. Bourne, F. Gieseler, F. Boege, H. Biersack, B. Spohn, M. Clark, K. Wilms, Fritz Boege, Frank Gieseler, Harald Biersack, Michael Clark, Klaus Wllms, Axel Polack, Lothar Strobl, Regina Feederle, Matthias Schweizer, Dirk Eick, Georg W. Bornkamm, M. Kopun, H. Scherthan, C. Granzow, P. Janiaud, D. Rueß, B. M. Mechler, P. G. Strauss, V. Erfle, M. Fritsche, C. Haessler, H. Christiansen, J. Schestag, N. M. Christiansen, F. Lampert, Wolfgang A. Schulz, Andreas Hasse, Helmut Sies, G. Orend, I. Kuhlmann, W. Doerfler, A. Behn-Krappa, I. Hölker, U. Sandaradura de Silva, Ute Smola, Dagmar Hennig, Angelika Hadviger-Fangmeier, Burkhard Schütz, R. Kerler, H. M. Rabes, G. Dölken, A. A. Fauser, R. Kerkert, U. Ragoczy, R. Fritzen, W. Lange, J. Finke, B. Nowicki, E. Schalipp, W. Siegert, R. Mertelsmann, U. Schilling, H. J. Sinn, W. Maier-Borst, E. A. Friedrich, E. Löhde, M. Lück, H. Raude, H. Schlicker, G. Barzen, E. Kraas, J. Milleck, R. Keymer, S. Störkel, T. Reichert, F. Steinbach, R. Lippold, W. Thoenes, W. Wagner, K. -A. Reiffen, A. Bardosi, D. Brkovic, H. -J. Gabius, B. Brandt, C. Jackisch, D. Seitzer, M. Hillebrand, F. A. Habermann, null Zeindl-Eberhart, null Evelyn, C. Robl, V. Röttgen, C. Nowak, H. -B. Richter-Reichhelm, V. Waldmann, B. Suchy, Ch. Zietz, M. Sarafoff, Richard Ostermayr, Hartmut M. Rabes, J. Lorenz, T. Friedberg, W. Paulus, R. Ferlinz, F. Oesch, E. Jähde, K. -H. Glüsenkamp, L. F. Tietze, M. F. Rajewsky, G. Chen, K. -J. Hutter, J. Bullerdiek, W. J. Zeller, M. Schirner, M. R. Schneider, P. Zbu, M. Gebelein, B. Naser-Hijazi, Nancy E. Hynes, M. Reinhardt, P. Heyl, D. Schmähl, P. Presek, U. Liebenhoff, D. Findik, G. H. Hartmann, C. Kliesch, F. Albert, S. Kunze, M. Wannnenmacher, J. Boese-Landgraf, E. Lorenz, D. Albrecht, M. Dulce, K. R. Aigner, N. Thiem, H. Müller, M. Leonardi, A. Justh, M. Lutz, E. Lang, C. W. v. d. Lieth, H. Sinn, B. R. Betsch, Jan Georg Hengstler, Jürgen Fuchs, Franz Oesch, F. J. Busch, A. B. C. Cato, G. Schied, W. Tang, B. Richter, C. Schaefer, D. K. Kelleher, P. Vaupel, D. Mundt, H. H. Bartsch, H. Meden, M. Meyer, K. Vehmeyer, R. Mull, W. Kuhn, S. Hoffmann, D. Berger, H. Fiebig, Ch. Moog, B. Luu, S. Frühauf, B. K. Keppler, A. Galeano, P. Valenzuela-Paz, T. Klenner, H. Stadler, G. Golomb, E. Breuer, R. Voegeli, P. Hilgard, H. R. Nowrousian, P. Aulenbacher, B. Winterhalter, C. Granson, M. Stöhr, H. Ponstingl, P. Drings, H. Osswald, S. B. Sobottka, E. Amtmann, G. Sauer, B. Hornung, S. Volland, S. Kahl, R. Gerspach, B. Matz, J. Schmidt, M. Lipp, G. Brehm, A. Luz, S. Wendel, P. G. Strauß, V. Erflte, S. Greehmann, A. Zobel, F. Kalkbrenner, G. Vorbrüggen, K. Moelling, T. Iftner, A. H. Müller, P. G. Fuchs, H. Pfister, Klaus Cichutek, Iris Treinies, Matthias Lang, C. Braun, J. Denner, S. Norley, R. Kurth, L. Music, O. D. Wiestler, A. Aguzzi, A. von Deimling, M. Schneemann, R. Elbl, P. Kleihues, H. Land, H. -P. Hohn, M. Höök, H. -W. Denker, W. Kemmner, K. Zaar, Peter A. Jones, R. Kath, M. Herlyn, P. Maier, H. P. Schawalder, J. Elsner, W. Parzefall, E. Erber, R. Sedivy, R. Schulte-Hermann, J. Hemmer, P. Tomakidi, P. Boukamp, D. Breitkreutz, N. E. Fusenig, F. Kallinowski, W. Strauss, A. L. Brownell, I. D. Bassukas, G. Vester, B. Maurer-Schultze, L. Langbein, H. Kosmehl, D. Katenkamp, Eberhard Spiess, Günther Trefz, Werner Ebert, Peter Jordan, Dieter Kübler, Rosemarie B. Lichtner, Marion Wiedemuth, Annette Kittmann, Axel Ullrich, Khashayarsha Khazaie, Aiga Kowitz, Guni Kadmon, Peter Altevogt, U. H. Frixen, J. Behrens, J. Schipper, M. Sachs, H. Birchmeier, R. Hackenberg, Th. Hawighorst, J. Hofmann, H. Beato, K. -D. Schulz, C. Erbil, M. Maasberg, L. A. Kunz, A. Simm, G. Adam, W. Mueller-Klieser, Andreas M. Kaufmann, Michael Stoeck, A. Hülsen, S. Game, M. Donnelly, H. -J. Stark, K. -H. Schlingensiepen, U. Kurzik-Dumke, B. Phannavong, D. Gundacker, E. Gateff, S. Gabius, S. S. Joshi, H. Franz, N. J. John, R. Grümmer, H. W. Denker, M. W. Gross, and U. Karbach

Subjects
Cancer Research, Oncology, General Medicine
Published
1991

13. The design and development of a digital photogrammetric stereo workstation

Author

Karsten Jacobsen, J. Weidenhammer, G. Picht, L. Skog, and P. Lohmann

Subjects
Data processing, Workstation, business.industry, Computer science, Orientation (computer vision), ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Orthophoto, Image processing, Stereo display, Atomic and Molecular Physics, and Optics, Computer Science Applications, law.invention, Photogrammetry, Aerial photography, law, Computer graphics (images), Computer vision, Artificial intelligence, Computers in Earth Sciences, business, Engineering (miscellaneous)
Abstract

The design and implementation of a digital photogrammetric stereo workstation based on a commercially available image processing system, the GOP 302, is presented. Aspects of theoretical background and practical implementation are discussed and first results obtained during the test phase are presented. The system includes a stereo display, measurement and orientation programs as well as a package for digital correlation and orthophoto production for aerial photography and SPOT images.

Published
1989

14. Die Zeit und die Modalitäten

Author

G. Picht

Abstract

Alles, was ist, ist in der Zeit. Alles, was gewesen ist, ist in der Zeit gewesen. Alles, was sein wird, wird in der Zeit sein. Die Verbalformen: „es ist“, „es ist gewesen“, „es wird sein“ bezeichnen verschiedene „Modi“ der Zeit. Was immer der Begriff „Modi“ bedeuten mag — jedenfalls vermogen wir Gegenwart, Vergangenheit und Zukunft nur zu unterscheiden, indem wir zugleich annehmen, das die Zeit in dieser Differenz eine Einheit ist. In diesem Sinne ist die Einheit der Zeit der universale Horizont fur alles, von dem wir sagen konnen, das es ist, das es gewesen ist, und das es sein wird. Unsere Erkenntnis alles dessen, was — in den drei Modi der Zeit — ist, wird also stets durch jenes Vorverstandnis bestimmt, das wir von der Einheit der Zeit, sei es auch noch so unartikuliert, mitbringen. Jedes Objekt, jede Struktur, jede Relation, jedes Gesetz, das wir erkennen oder zu erkennen glauben, ist zugleich ein Spiegel jenes Vorverstandnisses der Einheit der Zeit, das menschliches Erkennen allererst moglich macht. In diesem Sinne kann man sagen: was wir „die Wahrheit“ nennen, ist die Erscheinung der Einheit der Zeit, die sich in jeder einzelnen Erkenntnis widerspiegelt.

Published
1971

15. Ferroelastic Properties of PZT: Characterization Under Compressive and Tensile Stress, Finite-Element Simulation, and Lifetime Calculation.

Author

Picht G, Bouvier V, Frank S, Koruza J, Felten F, and Lindemann G

Abstract

Finite-element (FE) simulations, based on a phenomenological nonlinear constitutive model, were carried out to show the impact of ferroelastic switching on compressive and tensile loading of a soft and hard ferroelastic polycrystalline lead zirconate titanate ceramic (PbZr1-xTixO3, PZT). Hereby, a model assembly is used that simulates mechanical stresses generated by the contact of a ceramic element with a concave counterpart. In order to parameterize the constitutive model, the elastic and piezoelectric tensors are determined by the small signal resonance method and by the direct measurement under compressive/tensile loads. In addition, the large field ferroelectric and ferroelastic behavior of polarization and strain were characterized. The simulations show that the tensile stress level within the piezoceramic is much lower compared to a linear elastic model, which is related to ferroelastic switching. This is demonstrated to have a significant influence on mechanical lifetime predictions. To validate the parametrized FE model, a four-point bending experiment was used. The comparison of the calculated and measured strain on the compressive and tensile sides of the sample showed very good correlation.

Published
2018
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16. Influence of argon laser trabeculoplasty on transforming growth factor-beta 2 concentration and bleb scarring following trabeculectomy.

Author

Wimmer I, Welge-Luessen U, Picht G, and Grehn F

Subjects
Argon, Blister complications, Humans, Osmolar Concentration, Prospective Studies, Risk Factors, Trabeculectomy methods, Transforming Growth Factor beta2, Aqueous Humor metabolism, Cicatrix etiology, Exfoliation Syndrome surgery, Glaucoma, Open-Angle surgery, Laser Therapy adverse effects, Trabeculectomy adverse effects, Transforming Growth Factor beta metabolism
Abstract

Background: The purpose of this study was to evaluate the influence of previous argon laser trabeculoplasty (ALT) on transforming growth factor-beta 2 (TGF-beta 2) concentration of the aqueous humor and its influence on bleb scarring after trabeculectomy., Methods: Fifty-one patients with primary open-angle glaucoma (POAG) and 29 patients with exfoliation (XFS) glaucoma were recruited for this prospective study before undergoing trabeculectomy. Sixty to 200 micro l of aqueous humor were analyzed for total and biologically active TGF-beta 2 concentrations (R and D Systems). TGF-beta 2 levels and a standardized bleb assessment were compared between the ALT- and non-ALT-treated groups., Results: POAG eyes without ALT showed significantly higher total TGF-beta 2 levels (2,317.7+/-1,041.1 pg/ml) than eyes with previous ALT (1,621.6+/-899.6 pg/ml; P=0.026). No significant difference was found for active TGF-beta 2 levels (ALT: 238.1+/-119.0 pg/ml; no ALT: 220.1+/-96.9 pg/ml; P=0.585). In XFS patients ALT did not alter total TGF-beta 2 levels (ALT: 1,524.9+/-624.9 pg/ml, no ALT: 1,220+/-499.1 pg/ml; P=0.20), but active TGF-beta 2 was significantly higher in the ALT-treated (237.0+/-99.7 pg/ml) than in the non-ALT-treated (140.0+/-95.3 pg/ml, P=0.028) group. Bleb grading revealed no statistical difference between the ALT- and non-ALT-treated groups in POAG (P=0.545, Fisher's exact test), whereas XFS patients with ALT were at increased risk for scarring compared to non-ALT-treated patients (P=0.053)., Conclusions: ALT appears to increase the risk of scarring in XFS patients because of increased levels of activated TGF-beta 2.

Published
2003
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17. [Follow-up of trabeculectomy. Complications and therapeutic consequences].

Author

Picht G, Mutsch Y, and Grehn F

Subjects
Adult, Aged, Aged, 80 and over, Cicatrix etiology, Cicatrix surgery, Combined Modality Therapy, Female, Follow-Up Studies, Humans, Male, Middle Aged, Postoperative Complications surgery, Reoperation, Risk Factors, Aftercare, Glaucoma surgery, Postoperative Complications etiology, Trabeculectomy
Abstract

Background: Intensive follow-up after trabeculectomy is important for long-term success. In the postoperative period, complications must be detected early in order to initiate adequate therapeutic measures., Patients and Methods: In a retrospective study 113 eyes from 113 consecutive patients were followed-up for a period of 6 months after trabeculectomy with regard to postoperative complications and therapeutic decisions (invasive and conservative). Criteria of success were defined as an intraocular pressure (IOP) < 21 mmHg without antiglaucomatous treatment as well as an IOP reduction > 20% compared to the preoperatively treated IOP., Results: Most of the postoperative complications occurred within the first 3 weeks: scarring of the filtering bleb (47.6%), choroidal detachment (18.6%), shallowing of the anterior chamber (8%), fibrinous reaction (5.3%), overfiltration (4.4%), reduced flow under the scleral flap (4.4%), corneal dellen (3.5%), prolapse of the iris (3.5%), external fistulation (2.7%), increase of the IOP due to steroids (1.8%), detachment of the ciliary body (1.8%) and malignant glaucoma (0.9%). In the postoperative period, 45.1% of the eyes needed further interventions such as 5-fluorouracil (5-FU) injections (28.3%), needling and 5-FU-injections (14.2%), laser suturolysis (6.2%). Repositioning of the iris, YAG-laser iridotomy, laser treatment of the filtering bleb, autologous blood injection and cyclocryoapplication were needed only in rare cases and 36.3% received other conservative treatment (i.e. modification of topical steroids, increase of cycloplegic treatment). After 6 months the success rate without antiglaucoma medication was 88.5%., Conclusions: An intensive follow-up after trabeculectomy is mandatory to avoid postoperative failure. In about half of the patients postoperative additional therapeutic measures became necessary, particularly if scarring of the filtering bleb occurred. Paying attention to these factors yields in a high success rate after filtering surgery.

Published
2001
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18. The presence and properties of myocilin in the aqueous humor.

Author

Russell P, Tamm ER, Grehn FJ, Picht G, and Johnson M

Subjects
Animals, Blotting, Western, Cataract complications, Cataract metabolism, Cataract Extraction, Cattle, Chromatography, Gel, Cytoskeletal Proteins, Electrophoresis, Polyacrylamide Gel, Glaucoma complications, Glaucoma metabolism, Glaucoma surgery, Humans, Macaca, Molecular Weight, Aqueous Humor metabolism, Eye Proteins metabolism, Glycoproteins metabolism
Abstract

Purpose: To determine whether myocilin is present in the aqueous humor (AH) and to examine certain properties of this protein., Methods: Human AH was obtained at the time of either glaucoma surgery or cataract extraction. Monkey AH was obtained at the time of death, and bovine aqueous was obtained from eyes delivered from an abattoir. Column chromatography was performed on aqueous samples to determine the approximate size of the myocilin present. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot analysis were performed using antibody prepared against a peptide sequence in myocilin. Analysis of the bovine proteins present in AH that were retained by a microporous filter was also performed using western blot analysis., Results: By western blot analysis, myocilin was present in human, monkey, and bovine AH. The apparent molecular size of the myocilin present in the AH were greater than 250,000 Da, when quantified with a gel filtration column. Myocilin appeared to be hydrophobic and was one of the proteins that was retained on microporous filters that were obstructed by AH., Conclusions: Myocilin is a constituent in the AH. It appears that myocilin is a hydrophobic protein that may exist in an oligomeric state or in association with other proteins. Myocilin is retained by microporous filters and may be involved in the obstruction of these filters that occurs when AH is perfused through them.

Published
2001

19. Transforming growth factor beta 2 levels in the aqueous humor in different types of glaucoma and the relation to filtering bleb development.

Author

Picht G, Welge-Luessen U, Grehn F, and Lütjen-Drecoll E

Subjects
Adolescent, Adult, Aged, Aged, 80 and over, Child, Preschool, Enzyme-Linked Immunosorbent Assay, Exfoliation Syndrome metabolism, Female, Glaucoma, Open-Angle classification, Glaucoma, Open-Angle surgery, Humans, Male, Middle Aged, Surgical Flaps, Transforming Growth Factor beta2, Aqueous Humor metabolism, Eye Proteins metabolism, Glaucoma, Open-Angle metabolism, Trabeculectomy, Transforming Growth Factor beta metabolism
Abstract

Purpose: To investigate the transforming growth factor beta 2 (TGF-beta 2) levels and total protein levels in the aqueous humor of eyes with different types of glaucoma [primary open-angle glaucoma (POAG), pseudoexfoliation glaucoma (PSX), juvenile glaucoma (JG)], and the relation to filtering bleb development after trabeculectomy., Methods: Aqueous humor was collected at the beginning of surgery from 52 eyes with glaucoma (29 POAG eyes, 17 PSX eyes, 6 JG eyes) and from 29 control eyes that underwent cataract operation. TGF-beta 2 levels (intrinsically activated and total TGF-beta 2) using ELISA methods as well as total protein concentrations of the aqueous humor were determined. All preoperative clinical data of the glaucoma eyes (age, gender, IOP, previous treatment, type of surgery) were compared with the TGF-beta 2 levels. In 40 of these eyes, the postoperative follow-up (filtering bleb development, need for intervention, IOP) was correlated to the preoperatively determined TGF-beta 2 levels., Results: TGF-beta 2 levels were increased in nearly half of the eyes with POAG and in most of the eyes with JG, but in eyes with PSX, TGF-beta 2 levels were within the normal range. No correlation between TGF-beta 2 levels and age, gender, IOP, previous treatment, or type of surgery, or between TGF-beta 2 levels and protein levels in aqueous humor, was found. Correlation between bleb formation and TGF-beta 2 levels revealed that all but two of the POAG eyes with good clinical outcome (type 1 bleb) had normal levels of activated TGF-beta 2. Of the 13 eyes that needed postoperative intervention (type 2 and type 3 bleb), 8 had high and 5 had normal TGF-beta 2 levels., Conclusions: PSX eyes differ from POAG and JG eyes not only by their clinical or biomicroscopic appearance, but also by their normal TGF-beta 2 levels in aqueous humor. The fact that most of the POAG eyes with favorable bleb development had normal TGF-beta 2 levels indicated that there might be some relationship between bleb formation and TGF-beta 2 levels. On the other hand, the fact that eyes with less favorable bleb development had both low and high TGF-beta 2 levels indicated that other factors are also involved in the scarring of the filtration bleb.

Published
2001
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21. Classification of filtering blebs in trabeculectomy: biomicroscopy and functionality.

Author

Picht G and Grehn F

Subjects
Aqueous Humor metabolism, Filtering Surgery classification, Glaucoma metabolism, Glaucoma surgery, Humans, Intraocular Pressure, Postoperative Complications physiopathology, Wound Healing, Glaucoma physiopathology, Trabeculectomy
Abstract

The long-term success of filtering surgery is not dependent on surgical technique alone. The development of the filtering bleb in the postoperative period, in particular with regard to wound healing and subconjunctival scarring, is equally important. Morphologic changes of the developing filtering bleb after trabeculectomy can predict early failure even if the intraocular pressure is still normal. A basic understanding of wound healing processes and histologic changes of the developing filtering bleb are mandatory to interpret correctly the morphologic appearance of the developing filtering bleb. In clinical practice, follow-up of the filtering bleb according to a standardized morphologic classification may help to predict outcome and provide clues for the necessity and timing of further treatment.

Published
1998
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22. Acetazolamide and CO2: acute effects on cerebral and retrobulbar hemodynamics.

Author

Harris A, Tippke S, Sievers C, Picht G, Lieb W, and Martin B

Subjects
Adult, Cerebral Arteries diagnostic imaging, Cerebral Arteries drug effects, Drug Combinations, Hemodynamics drug effects, Humans, Hypercapnia physiopathology, Intraocular Pressure drug effects, Ophthalmic Artery diagnostic imaging, Ophthalmic Artery drug effects, Reference Values, Retinal Artery diagnostic imaging, Retinal Artery drug effects, Ultrasonography, Doppler, Color, Vasodilation, Acetazolamide pharmacology, Carbon Dioxide pharmacology, Carbonic Anhydrase Inhibitors pharmacology, Cerebral Arteries physiology, Ophthalmic Artery physiology, Retinal Artery physiology
Abstract

Purpose: Acetazolamide and CO2 are cerebral vasodilators whose specific effects in various brain regions have not been carefully defined. We investigated the effects of these agents in both larger cerebral and smaller, retrobulbar arteries, to compare their general cerebral vasodilatory influence with their specific ocular vascular effects., Methods: Twelve young adults with healthy eyes were studied under normocapnic and hypercapnic (6% CO2, 94% O2 tanked gas) conditions after receiving either placebo or 1,000 mg acetazolamide (3 h before study). Color Doppler imaging was used to measure peak systolic and end-diastolic velocities (PSV and EDV) in the internal carotid, middle cerebral, ophthalmic, and central retinal arteries under each condition., Results: Acetazolamide and CO2 each lowered intraocular pressure; combining the agents provided no additive ocular hypotensive effect. Hypercapnia or acetazolamide per se failed to alter PSV, EDV, or the derived resistance index [RI; (PSV-EDV)/PSV] in the internal carotid or in either orbital artery. However, when hypercapnia was superimposed upon acetazolamide, the resistance index fell in the internal carotid and central retinal arteries (each p < 0.05). In contrast, the middle cerebral artery was responsive to either vasodilator and to their combination: PSV and EDV rose, and RI fell with each experimental treatment., Conclusions: In the brain, the middle cerebral artery exhibits substantial dependence of flow velocity on the vasodilators CO2 and acetazolamide. In contrast, the ophthalmic and central retinal arteries appear less responsive. Nonetheless, the combination of carbonic anhydrase inhibition (acetazolamide) with CO2 augmentation did lower vascular resistance distal to the central retinal artery, suggesting that this mechanism vasodilates critical ocular tissues.

Published
1996

23. Clonal analysis of the effect of TGF-beta on the apoptosis-inducing activity of normal cells.

Author

Picht G, Hundertmark N, Schmitt CP, and Bauer G

Subjects
3T3 Cells, Animals, Apoptosis drug effects, Blood Platelets physiology, Cell Line, Transformed, Clone Cells, Fibroblasts cytology, Fibroblasts drug effects, Fibroblasts physiology, Humans, Mice, Mice, Inbred C3H, Transforming Growth Factor beta isolation & purification, Apoptosis physiology, Transforming Growth Factor beta pharmacology
Abstract

We have recently described induction of apoptosis in transformed fibroblasts by transforming growth factor type beta (TGF-beta)-treated normal fibroblasts, which leads to the specific elimination of transformed cells. Here we investigate whether the ability to eliminate transformed cells is the property of a specialized subpopulation of normal fibroblasts or whether all cells within the population are able to respond to exogenous TGF-beta by induction of elimination of transformed cells. Clonal analysis of the eliminative capacity of normal fibroblasts showed that all cells are able to induce elimination after addition of optimal concentrations of exogenous TGF-beta. In the absence of exogenously added TGF-beta, a minority of clones exhibited complete eliminative activity. Neither the ability nor the inability to perform elimination in the absence of exogenous TGF-beta was a stable characteristic of the respective cell clones. The number of cell clones with the ability to respond to suboptimal concentrations of TGF-beta increased with the passage number of the normal cells, whereas the number of clones inducing apoptosis in the absence of exogenous TGF-beta remained constant.

Published
1995
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