TY - JOUR A1 - Kobus, Thiele A1 - Bitz, Andreas A1 - Uden, Mark J. van A1 - Lagemaat, Miram W. A1 - Rothgang, Eva A1 - Orzada, Stephan A1 - Heerschap, Arend A1 - Scheenen, Tom W. J. T1 - In vivo 31P MR spectroscopic imaging of the human prostate at 7 T: safety and feasibility JF - Magnetic Resonance in Medicine N2 - 31P MR spectroscopic imaging of the human prostate provides information about phosphorylated metabolites that could be used for prostate cancer characterization. The sensitivity of a magnetic field strength of 7 T might enable 3D 31P MR spectroscopic imaging with relevant spatial resolution in a clinically acceptable measurement time. To this end, a 31P endorectal coil was developed and combined with an eight-channel 1H body-array coil to relate metabolic information to anatomical location. An extensive safety validation was performed to evaluate the specific absorption rate, the radiofrequency field distribution, and the temperature distribution of both coils. This validation consisted of detailed Finite Integration Technique simulations, confirmed by MR thermometry and Burn:x-wiley:07403194:media:MRM24175:tex2gif-stack-1 measurements in a phantom and in vivo temperature measurements. The safety studies demonstrated that the presence of the 31P endorectal coil had no influence on the specific absorption rate levels and temperature distribution of the external eight-channel 1H array coil. To stay within a 10 g averaged local specific absorption rate of 10 W/kg, a maximum time-averaged input power of 33 W for the 1H array coil was allowed. For transmitting with the 31P endorectal coil, our safety limit of less than 1°C temperature increase in vivo during a 15-min MR spectroscopic imaging experiment was reached at a time-averaged input power of 1.9 W. With this power setting, a second in vivo measurement was performed on a healthy volunteer. Using adiabatic excitation, 3D 31P MR spectroscopic imaging produced spectra from the entire prostate in 18 min with a spatial resolution of 4 cm3. The spectral resolution enabled the separate detection of phosphocholine, phosphoethanolamine, inorganic phosphate, and other metabolites that could play an important role in the characterization of prostate cancer. Y1 - 2012 U6 - https://doi.org/10.1002/mrm.24175 SN - 1522-2594 VL - 68 IS - 6 SP - 1683 EP - 1695 PB - Wiley-Liss CY - New York ER - TY - JOUR A1 - Yazdanbakhsh, Pedram A1 - Solbach, Klaus A1 - Bitz, Andreas T1 - Variable power combiner for RF mode shimming in 7-T MR imaging JF - IEEE Transaction on Biomedical Engineering N2 - This contribution discusses the utilization of RF power in an MRI system with RF mode shimming which enables the superposition of circularly polarized modes of a transmit RF coil array driven by a Butler matrix. Since the required power for the individual modes can vary widely, mode-shimming can result in a significant underutilization of the total available RF power. A variable power combiner (VPC) is proposed to improve the power utilization: it can be realized as a reconfiguration of the MRI transmit system by the inclusion of one additional matrix network which receives the power from all transmit amplifiers at its input ports and provides any desired (combined) power distribution at its output ports by controlling the phase and amplitude of the amplifiers’ input signals. The power distribution at the output ports of the VPC is then fed into the “mode” ports of the coil array Butler matrix in order to superimpose the spatial modes at the highest achievable power utilization. The VPC configuration is compared to the standard configuration of the transmit chain of our MRI system with 8 transmit channels and 16 coils. In realistic scenarios, improved power utilization was achieved from 17% to 60% and from 14% to 55% for an elliptical phantom and a region of interest in the abdomen, respectively, and an increase of the power utilization of 1 dB for a region of interest in the upper leg. In general, it is found that the VPC allows significant improvement in power utilization when the shimming solution demands only a few modes to be energized, while the technique can yield loss in power utilization in cases with many modes required at high power level. Y1 - 2012 U6 - https://doi.org/10.1109/TBME.2012.2205926 SN - 1558-2531 VL - 59 IS - 9 SP - 2549 EP - 2557 PB - IEEE CY - New York ER - TY - JOUR A1 - Kroll-Ludwigs, Kathrin T1 - Ein optionales Vertragsrecht für Europa: Motor oder Hemmnis für den Binnenmarkt? JF - GPR : Zeitschrift für Gemeinschaftsprivatrecht Y1 - 2018 U6 - https://doi.org/10.1515/gpr.2012.9.4.181 SN - 2193-9519 VL - 9 IS - 4 SP - 181 EP - 188 PB - Verlag Dr. Otto Schmidt CY - Köln ER - TY - JOUR A1 - Chludek, Astrid A1 - Tran, Duc Hung T1 - Der Reformvorschlag des IAS 12 gem. ED/2009/2 - Ein Plädoyer für die Einführung der valuation allowance JF - KoR Zeitschrift für kapitalmarktorientierte Rechnungslegung Y1 - 2018 SN - 1617-8084 IS - 1 SP - 4 EP - 8 PB - Fachmedien Otto Schmidt CY - Düsseldorf ER - TY - JOUR A1 - Herzwurm, Georg A1 - Krams, Benedikt A1 - Pietsch, Wolfram A1 - Schockert, Sixten T1 - Report from the 3rd international workshop on requirements prioritization for customer oriented software development (RePriCo’12) JF - ACM SIGSOFT Software Engineering Notes N2 - Prioritization is an essential task within requirements engineering to cope with complexity and to establish focus properly. The 3rd Workshop on Requirements Prioritization for customer oriented Software Development (RePriCo’12) focused on requirements prioritization and adjacent themes in the context of customer oriented development of bespoke and standard software. Five submissions have been accepted for the proceedings and for presentation. The report summarizes and points out key findings. KW - Requirements relations KW - Discourse ethics KW - Tool support KW - Consensus KW - Requirements prioritization Y1 - 2012 U6 - https://doi.org/10.1145/2237796.2237817 SN - 0163-5948 VL - 37 IS - 4 SP - 32 EP - 34 PB - Association for Computing Machinery CY - New York ER - TY - CHAP A1 - Frühwald, Katja A1 - Peterson, Leif Arne A1 - Hasenstab, Andreas ED - Fouad, Nabil A. T1 - Prüfverfahren zur Begutachtung der Materialeigenschaften von Holztragwerken T2 - Bauphysik‐Kalender 2012: Schwerpunkt: Gebäudediagnostik N2 - Dieses Kapitel beinhaltet: - Einleitung - Ausgewählte typische Schäden an Holzbauwerken - Das Material Holz und seine Besonderheiten - Bestandserfassung - Labormethoden - Begutachtungsbeispiele - Zusammenfassung und Schlussfolgerungen - Literatur Y1 - 2012 SN - 9783433029862 (Print) SN - 9783433601235 (Online) U6 - https://doi.org/10.1002/9783433601235.ch4 SP - 103 EP - 155 PB - Ernst & Sohn CY - Berlin ER - TY - CHAP A1 - Butenweg, Christoph T1 - Eurocode 8 : Erdbebenauslegung von Tragwerken T2 - Eurocodes 2012 kompakt - Chancen nutzen : 36. Darmstädter Massivbauseminar Zukunftsfähiges Planen und Bauen, 7. und 8. März Y1 - 2012 SP - 257 EP - 272 PB - Freunde des Inst. für Massivbau der TU CY - Darmstadt ER - TY - CHAP A1 - Kuhlmann, Wolfram A1 - Butenweg, Christoph A1 - Meskouris, Konstantin A1 - Kempen, Thomas T1 - Simulation des Tragverhaltens des Aachener Doms im Erdbebenfall T2 - Die karolingische Pfalzkapelle in Aachen : Material, Bautechnik, Restaurierung. (Arbeitshefte der rheinischen Denkmalpflege ; 78) Y1 - 2012 SN - 978-3-88462-325-1 SP - 237 EP - 248 PB - Wernersche Verlags-Gesellschaft CY - Worms ER - TY - CHAP A1 - Butenweg, Christoph A1 - Roeser, W. T1 - Erdbebenbemessung von Stahlbetontragwerken nach DIN EN 1998-1 T2 - Stahlbetonbau aktuell : Praxishandbuch Y1 - 2012 SN - 978-3-410-21932-3 (Print) ; 978-341-02193-3-0 (E-Book) SP - A.1 EP - A.43 PB - Beuth CY - Berlin ER - TY - JOUR A1 - Stadler, Andreas M. A1 - Garvey, G. J. A1 - Bocahut, A. A1 - Sacquin-Mora, S. A1 - Digel, Ilya A1 - Schneider, G. J. A1 - Natali, F. A1 - Artmann, Gerhard A1 - Zaccai, G. T1 - Thermal fluctuations of haemoglobin from different species : adaptation to temperature via conformational dynamics JF - Journal of the Royal Society Interface N2 - Thermodynamic stability, configurational motions and internal forces of haemoglobin (Hb) of three endotherms (platypus, Ornithorhynchus anatinus; domestic chicken, Gallus gallus domesticus and human, Homo sapiens) and an ectotherm (salt water crocodile, Crocodylus porosus) were investigated using circular dichroism, incoherent elastic neutron scattering and coarse-grained Brownian dynamics simulations. The experimental results from Hb solutions revealed a direct correlation between protein resilience, melting temperature and average body temperature of the different species on the 0.1 ns time scale. Molecular forces appeared to be adapted to permit conformational fluctuations with a root mean square displacement close to 1.2 Å at the corresponding average body temperature of the endotherms. Strong forces within crocodile Hb maintain the amplitudes of motion within a narrow limit over the entire temperature range in which the animal lives. In fully hydrated powder samples of human and chicken, Hb mean square displacements and effective force constants on the 1 ns time scale showed no differences over the whole temperature range from 10 to 300 K, in contrast to the solution case. A complementary result of the study, therefore, is that one hydration layer is not sufficient to activate all conformational fluctuations of Hb in the pico- to nanosecond time scale which might be relevant for biological function. Coarse-grained Brownian dynamics simulations permitted to explore residue-specific effects. They indicated that temperature sensing of human and chicken Hb occurs mainly at residues lining internal cavities in the β-subunits. Y1 - 2012 U6 - https://doi.org/10.1098/rsif.2012.0364 SN - 1742-5689 VL - 9 IS - 76 SP - 2845 EP - 2855 PB - The Royal Society CY - London ER -