TY  - JOUR
A1  - Kearney, D.
A1  - Herrmann, Ulf
A1  - Nava, P.
A1  - Kelly, B.
A1  - Mahoney, R.
A1  - Pacheco, J.
A1  - Cable, R.
A1  - Potrovitza, N.
A1  - Blake, D.
A1  - Price, H.
T1  - Assessment of a Molten Salt Heat Transfer Fluid in a Parabolic Trough Solar Field
JF  - Journal of Solar Energy Engineering
Y1  - 2003
U6  - http://dx.doi.org/10.1115/1.1565087
SN  - 1528-8986
VL  - 125
IS  - 2
SP  - 170
EP  - 176
ER  - 
TY  - JOUR
A1  - Seibler, Jost
A1  - Zevnik, Branko
A1  - Küter-Luks, Birgit
A1  - Andreas, Susanne
A1  - Kern, Heidrun
A1  - Hennek, Thomas
A1  - Rode, Anja
A1  - Heimann, Cornelia
A1  - Faust, Nicole
A1  - Kauselmann, Gunther
A1  - Schoor, Michael
A1  - Jaenisch, Rudolf
A1  - Rajewsky, Klaus
A1  - Kühn, Ralf
A1  - Schwenk, Frieder
T1  - Rapid generation of inducible mouse mutants
JF  - Nucleic Acids Research
Y1  - 2003
U6  - http://dx.doi.org/10.1093/nar/gng012
SN  - 1362-4962
VL  - 33
IS  - 4
SP  - e12
ER  - 
TY  - JOUR
A1  - Hellwig, Angelika
A1  - Volkmann, Lutz
T1  - Maximally edge-connected digraphs
JF  - Australasian journal of combinatorics
Y1  - 2003
SN  - 1034-4942 (E-Journal); 1034-4942 (Print)
VL  - Vol. 27
SP  - 23
EP  - 32
ER  - 
TY  - JOUR
A1  - Krämer, Marco
A1  - Bongaerts, Johannes
A1  - Bovenberg, Roel
A1  - Kremer, Susanne
A1  - Müller, Ulrike
A1  - Orf, Sonja
A1  - Wubbolts, Marcel
A1  - Raeven, Leon
T1  - Metabolic engineering for microbial production of shikimic acid
JF  - Metabolic engineering
Y1  - 2003
SN  - 1096-7184 (E-Journal); 1096-7176 (Print)
VL  - Vol. 5
IS  - Iss. 4
SP  - 277
EP  - 283
ER  - 
TY  - JOUR
A1  - Palmer, J. W.
A1  - Lindemann, Markus
T1  - Business models and market mechanisms : evaluating efficiency in consumer electronic markets
JF  - Data base and advanced information systems. Bd. 34 (2003), H. 2
Y1  - 2003
SN  - 0105-9912
SP  - 23
EP  - 38
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Saleh, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - Pulse shape discrimination of LSO and LuYAP scintillators for depth of interaction detection in PET
JF  - IEEE Transactions on Nuclear Science
N2  - A feasible way to gain the depth of interaction information in a positron emission tomography scanner is the use of phoswich detectors. In general, the layer of interaction is identified from the pulse shape of the corresponding scintillator material. In this work, pulses from LSO and LuYAP crystals were investigated in order to find a practical method of distinguishing. It turned out that such a pulse processing could be kept simple because of an additional slow component in the light decay of the LuYAP pulse. At the same time, the short decay time guarantees that the major amount of the light output is still collected within a short pulse recording time.
Y1  - 2003
SN  - 0018-9499
VL  - 50
IS  - 3
SP  - 344
EP  - 347
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Saleh, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - Pulse shape discrimination of LSO and LuYAP scintillators for depth of interaction detection in PET
JF  - 2002 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - A feasible way to gain the depth of interaction information in a PET scanner is the use of phoswich detectors. In general the layer of interaction is identified front the pulse shape of the corresponding scintillator material. In this work pulses from LSO and LuYAP crystals were investigated in order to find a practical method of distinguishing. It turned out that such a pulse processing could he kept simple due to an additional slow component in the light decay of the LuYAP pulse. At the same time the short decay time guarantees that the major amount of the light output is still collected within a short pulse recording time.
Y1  - 2003
SN  - 1082-3654
SP  - 1636
EP  - 1639
ER  - 
TY  - JOUR
A1  - Heinrichs, U.
A1  - Pietrzyk, U.
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  - Heinrichs, U.
A1  - Pietrzyk, U.
A1  - Ziemons, Karl
T1  - Design optimization of the PMT-ClearPET prototypes based on simulation studies with GEANT3
JF  - 2002 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - Within the Crystal Clear Collaboration four centres are developing 2nd generation high performance small animal PET scanners for different kinds of animals and medical applications. The first prototypes are PMT-based systems including depth of interaction (DOI) detection by using a phoswich layer of LSO and LuYAP. The aim of these simulation studies is to optimize sensitivity and spatial resolution of given designs, which vary in FOVs caused by different detector configurations (ring/octagon) and sizes. For this purpose the simulation tool GEANT3 (CERN) was used. The simulations have shown that all PMT designs with one-to-one coupling of crystals have a very nonlinear axial sensitivity profile. By shifting every other PMT 1/4 of a PMT length in axial direction the sampling of the FOVs became more homogeneous. At an energy threshold of 350keV the regression coefficient increases from 0.818 for the non-shifted to 0.993 for the shifted design. Simulations of a point source centred in the FOV (threshold: 350keV) resulted in sensitivities of 4.2% for a 4×20PMT (LSO/LuYAP a 10mm) and 3.8% for a 4×16PMT (LSO/LuYAP a 8mm) ring design. The 3D-MLEM reconstruction of a point source shows the enormous improvement of resolution using a crystal double layer with DOI (3.1mm at 40mm from CFOV) instead of a 20mm single layer (11.9mm).
Y1  - 2003
SN  - 1082-3654
SP  - 682
EP  - 686
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Schmidt, Tanja D.
A1  - Seboldt, Wolfgang
A1  - Auweter-Kurtz, 
T1  - Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika
Y1  - 2003
N1  - 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit
20-23 July 2003, Huntsville, Alabama ; AIAA 2003-4573
SP  - 1
EP  - 9
PB  - -
ER  -