TY - JOUR A1 - Schöning, Michael Josef A1 - Arzdorf, Michael A1 - Mulchandani, P. A1 - Chen, W. A1 - Mulchandani, A. T1 - Towards a capacitive enzyme sensor for direct determination of organophosphorus pesticides: Fundamentals studies and aspects of development JF - Sensors. 3 (2003), H. 6 Y1 - 2003 SN - 1424-8220 SP - 119 EP - 127 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Arzdorf, Michael A1 - Mulchandani, P. A1 - Chen, W. A1 - Mulchandani, A. T1 - A capacitive field-effect sensor for the direct determination of organophosphorus pesticides JF - Sensors and Actuators B. 91 (2003), H. 1-3 Y1 - 2003 SN - 0925-4005 SP - 92 EP - 97 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak A1 - Schultze, Joachim W. T1 - Measuring seven parameters by two ISFET modules in a microcell set-up JF - Int. Journal of Computational Engineering Science. 4 (2003), H. 2 Y1 - 2003 SN - 1465-8763 SP - 257 EP - 260 ER - TY - BOOK A1 - Staat, Manfred A1 - Heitzer, Michael T1 - Numerical methods for limit and shakedown analysis. Deterministic and probabilistic problems. Y1 - 2003 SN - 3-00-010001-6 N1 - NIC Series Vol. 15 / Ed. by Staat, M; Heitzer, M. PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - JOUR A1 - Baroud, Gamal A1 - Wu, J.Z. A1 - Bohner, M A1 - Sponagel, Stefan A1 - Steffen, T. T1 - How to determine the permeability for cement infiltration into osteoporotic cancellous bone JF - Medical Engineering & Physics. 25 (2003), H. 4 N2 - Cement augmentation is an emerging surgical procedure in which bone cement is used to infiltrate and reinforce osteoporotic vertebrae. Although this infiltration procedure has been widely applied, it is performed empirically and little is known about the flow characteristics of cement during the injection process. We present a theoretical and experimental approach to investigate the intertrabecular bone permeability during the infiltration procedure. The cement permeability was considered to be dependent on time, bone porosity, and cement viscosity in our analysis. In order to determine the time-dependent permeability, ten cancellous bone cores were harvested from osteoporotic vertebrae, infiltrated with acrylic cement at a constant flow rate, and the pressure drop across the cores during the infiltration was measured. The viscosity dependence of the permeability was determined based on published experimental data. The theoretical model for the permeability as a function of bone porosity and time was then fit to the testing data. Our findings suggest that the intertrabecular bone permeability depends strongly on time. For instance, the initial permeability (60.89 mm4/N.s) reduced to approximately 63% of its original value within 18 seconds. This study is the first to analyze cement flow through osteoporotic bone. The theoretical and experimental models provided in this paper are generic. Thus, they can be used to systematically study and optimize the infiltration process for clinical practice. KW - Osteoporose KW - Permeabilität KW - Viskose Strömung KW - Viskosität KW - Vertebroplastie KW - Cement infiltration KW - Vertebroplasty KW - Osteoporosis KW - Permeability KW - Experiment KW - Analysis KW - Viscous flow Y1 - 2003 SN - 1350-4533 SP - 283 EP - 288 ER - TY - JOUR A1 - Heinrichs, U. A1 - Pietrzyk, Uwe A1 - Ziemons, Karl T1 - Design optimization of the PMT-ClearPET prototypes based on simulation studies with GEANT3 JF - IEEE Transactions on Nuclear Science N2 - Within the Crystal Clear Collaboration (CCC), four centers are developing second generation high performance small animal positron emission tomography (PET) scanners for different kinds of animals and medical applications. The first prototypes are photomultiplier tube (PMT)-based systems including depth of interaction (DOI) detection by using a phoswich layer of lutetium oxyorthosilicate (LSO) and lutetium yttrium aluminum perovskite (LuYAP). The aim of these simulation studies is to optimize sensitivity and spatial resolution of given designs, which vary in fields of view (FOVs) caused by different detector configurations (ring/octagon) and sizes. For this purpose the simulation tool GEANT3 (CERN, Geneva, Switzerland) was used. Y1 - 2003 SN - 0018-9499 VL - 50 IS - 5 SP - 1428 EP - 1432 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Schubert, J A1 - Kloock, Joachim P. A1 - Zander, W. A1 - Mourzina, Y. G. A1 - Legin, A. A1 - Vlasov, Y. G. A1 - Lüth, H. T1 - Innovative thin film techniques for microfabricating electrochemical sensors JF - Lecture Notes of the ICB Seminars Y1 - 2002 SP - 55 EP - 66 PB - MCB CY - Warsaw ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Lüth, H. T1 - Microfabricated semiconductor structures – Advances in (bio-)chemical sensing JF - Coupling of biological and electronic systems : proceedings of the 2nd Caesarium, Bonn, November 1 - 3, 2000 / Karl-Heinz Hoffmann, ed. Y1 - 2002 SN - 3-540-43699-5 SP - 79 EP - 92 PB - Springer CY - Berlin [u.a.] ER - TY - JOUR A1 - Schroth, P. A1 - Weißbecker, B. A1 - Schütz, S. A1 - Ecken, H. A1 - Yoshinobu, T. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Bioelectronic signal processing - intact chemoreceptors coupled to field-effect devices JF - Lecture Notes of the ICB Seminars Y1 - 2002 SP - 28 EP - 42 PB - MCB CY - Warsaw ER - TY - JOUR A1 - Schöning, Michael Josef T1 - Novel approaches to design siliconbased field-effect sensors JF - Electrochemical Microsystem Technologies, New Trends in Electrochemistry Vol. 2 Y1 - 2002 SP - 384 EP - 408 PB - Taylor & Francis CY - London New York ER -