TY - JOUR A1 - Fredebeul-Krein, Markus T1 - TTIP : warum ein Investitionsschutzabkommen wünschenswert ist JF - Ordnungspolitischer Kommentar / Institut für Wirtschaftspolitik an der Universität zu Köln Y1 - 2015 IS - 02 SP - 1 EP - 2 ER - TY - JOUR A1 - Fredebeul-Krein, Markus T1 - Ziele der Sozial- und Verteilungspolitik JF - Das Wirtschaftsstudium : wisu ; Zeitschrift für Ausbildung, Prüfung, Berufseinstieg und Fortbildung Y1 - 2014 SN - 0340-3084 VL - 43 IS - 7 SP - 907 EP - 912 PB - Lange CY - Düsseldorf ER - TY - JOUR A1 - Fredebeul-Krein, Markus T1 - Wirtschaftskrise : Staatliche Förderung von glasfaserbasierten Breitbandnetzen? JF - Wirtschaftsdienst N2 - Glasfaserbasierte Breitbandnetze werden in Deutschland auch aufgrund der Wirtschaftskrise nur sehr zögerlich ausgebaut. Markus Fredebeul-Krein hält eine staatliche Subventionierung der Breitbandnetze nur bedingt für gerechtfertigt. Private Investoren benötigen jedoch dringend Planungssicherheit durch verlässliche Regulierungsvorschriften. Y1 - 2010 SN - 0043-6275 VL - 90 IS - 2 SP - 113 EP - 117 PB - ZBW CY - Berlin ER - TY - JOUR A1 - Fredebeul-Krein, Markus T1 - Die Abschaffung der Studiengebühren ist der falsche Weg! JF - Der Ordnungspolitische Kommentar Y1 - 2010 N1 - Herausgegeben vom Institut für Wirtschaftspolitik an der Universität zu Köln sowie dem Otto-Wolff-Institut für Wirtschaftsordnung ER - TY - JOUR A1 - Fredebeul-Krein, Markus ED - Bartoldus, Beate ED - John-Ohnesorg, Marei T1 - Sollen die Studiengebühren wieder abgeschafft werden? JF - Bildungsgerechtigkeit in der Begabtenförderung. Ein Widerspruch in sich? N2 - In den letzten Jahren haben in Deutschland mehrere Bundesländer Studiengebühren eingeführt. Seitdem wird in der Politik heftig über das Für und Wider diskutiert. Von den Gegnern wird häufig das Argument vorgebracht, Studiengebühren seien sozial ungerecht und würden insbesondere einkommensschwache Bevölkerungsschichten von einem Studium abhalten. Bestätigt werden sie von den Zahlen aus Umfragen, denen zufolge über 70 Prozent derjenigen, die sich gegen ein Studium entscheiden, finanzielle Gründe für einen Studienverzicht anführen. Befürworter halten dem entgegen, Studiengebühren seien angesichts knapper öffentlicher Kassen unbedingt notwendig, da nur so die Qualität der Lehre aufrechterhalten bzw. verbessert werden könne. Zudem würden Studiengebühren die sozialen Bildungsbarrieren keineswegs erhöhen, was auch daran erkennbar sei, dass infolge der Studiengebühren die Zahl der Studierenden nicht zurückgegangen ist. Der vorliegende Artikel leistet einen Beitrag zu dieser Debatte, indem er die an einer Hochschule in Nordrhein-Westfalen gesammelten Erfahrungen mit Studiengebühren auswertet Y1 - 2010 SN - 978-3-86872-423-3 SP - 124 EP - 129 PB - Friedrich-Ebert-Stiftung CY - Berlin ER - TY - JOUR A1 - Fredebeul-Krein, Markus T1 - Studiengebühren sind sozial gerecht JF - INSM-Ökonomenblog Y1 - 2010 PB - INSM CY - Berlin ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Niendorf, Thoralf A1 - Kob, Malte T1 - Acoustic method for synchronization of Magnetic Resonance Imaging (MRI) JF - Acta Acustica N2 - Magnetic Resonance Imaging (MRI) of moving organs requires synchronization with physiological motion or flow, which dictate the viable window for data acquisition. To meet this challenge, this study proposes an acoustic gating device (ACG) that employs acquisition and processing of acoustic signals for synchronization while providing MRI compatibility, immunity to interferences with electro-magnetic and acoustic fields and suitability for MRI at high magnetic field strengths. The applicability and robustness of the acoustic gating approach is examined in a pilot study, where it substitutes conventional ECG-gating for cardiovascular MR. The merits and limitations of the ACG approach are discussed. Implications for MR imaging in the presence of physiological motion are considered including synchronization with other structure- or motion borne sounds. Y1 - 2008 U6 - https://doi.org/10.3813/AAA.918017 SN - 1861-9959 VL - 94 IS - 1 SP - 148 EP - 155 PB - Hirzel CY - Stuttgart ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Hezel, Fabian A1 - Renz, Wolfgang A1 - de Geyer d'Orth, Thibaut A1 - Dieringer, Matthias A1 - von Knobelsdorf-Brenkenhoff, Florian A1 - Prothmann, Marcel A1 - Schulz-Menger, Jeanette A1 - Niendorf, Thoralf T1 - Acoustic cardiac triggering: a practical solution for synchronization and gating of cardiovascular magnetic resonance at 7 Tesla JF - Journal of Cardiovascular Magnetic Resonance N2 - Background To demonstrate the applicability of acoustic cardiac triggering (ACT) for imaging of the heart at ultrahigh magnetic fields (7.0 T) by comparing phonocardiogram, conventional vector electrocardiogram (ECG) and traditional pulse oximetry (POX) triggered 2D CINE acquisitions together with (i) a qualitative image quality analysis, (ii) an assessment of the left ventricular function parameter and (iii) an examination of trigger reliability and trigger detection variance derived from the signal waveforms. Results ECG was susceptible to severe distortions at 7.0 T. POX and ACT provided waveforms free of interferences from electromagnetic fields or from magneto-hydrodynamic effects. Frequent R-wave mis-registration occurred in ECG-triggered acquisitions with a failure rate of up to 30% resulting in cardiac motion induced artifacts. ACT and POX triggering produced images free of cardiac motion artefacts. ECG showed a severe jitter in the R-wave detection. POX also showed a trigger jitter of approximately Δt = 72 ms which is equivalent to two cardiac phases. ACT showed a jitter of approximately Δt = 5 ms only. ECG waveforms revealed a standard deviation for the cardiac trigger offset larger than that observed for ACT or POX waveforms. Image quality assessment showed that ACT substantially improved image quality as compared to ECG (image quality score at end-diastole: ECG = 1.7 ± 0.5, ACT = 2.4 ± 0.5, p = 0.04) while the comparison between ECG vs. POX gated acquisitions showed no significant differences in image quality (image quality score: ECG = 1.7 ± 0.5, POX = 2.0 ± 0.5, p = 0.34). Conclusions The applicability of acoustic triggering for cardiac CINE imaging at 7.0 T was demonstrated. ACT's trigger reliability and fidelity are superior to that of ECG and POX. ACT promises to be beneficial for cardiovascular magnetic resonance at ultra-high field strengths including 7.0 T. KW - Interval Time Series KW - Image Quality Score KW - Image Quality Assessment KW - Sound Pressure Level KW - Cardiovascular Magnetic Resonance Y1 - 2010 U6 - https://doi.org/10.1186/1532-429X-12-67 SN - 1532-429X VL - 12 IS - 1 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Hezel, Fabian A1 - Heinrichs, Uwe A1 - Kozerke, Sebastian A1 - Utting, Jane A1 - Kob, Malte A1 - Butenweg, Christoph A1 - Boesiger, Peter A1 - Niendorf, Thoralf T1 - Feasibility of Cardiac Gating Free of Interference With Electro-Magnetic Fields at 1.5 Tesla, 3.0 Tesla and 7.0 Tesla Using an MR-Stethoscope JF - Investigative Radiology KW - phonocardiogram KW - electrocardiogram KW - cardiac gating KW - high field MR imaging KW - cardiovascular MR imaging Y1 - 2009 U6 - https://doi.org/10.1097/RLI.0b013e3181b4c15e SN - 1536-0210 (online) SN - 0020-9996 (gedruckt) VL - 44 IS - 9 SP - 539 EP - 547 PB - Lippincott Williams & Wilkins ; (via Ovid) CY - Philadelphia, Pa ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Fuchs, Katharina A1 - Dieringer, Matthias A. A1 - Özerdem, Celal A1 - Patel, Nishan A1 - Renz, Wolfgang A1 - Greiser, Andreas A1 - Elgeti, Thomas A1 - Niendorf, Thoralf T1 - Detailing the use of magnetohydrodynamic effects for synchronization of MRI with the cardiac cycle: A feasibility study JF - Journal of Magnetic Resonance Imaging N2 - Purpose: To investigate the feasibility of using magnetohydrodynamic (MHD) effects for synchronization of magnetic resonance imaging (MRI) with the cardiac cycle. Materials and Methods: The MHD effect was scrutinized using a pulsatile flow phantom at B0 = 7.0 T. MHD effects were examined in vivo in healthy volunteers (n = 10) for B0 ranging from 0.05–7.0 T. Noncontrast-enhanced MR angiography (MRA) of the carotids was performed using a gated steady-state free-precession (SSFP) imaging technique in conjunction with electrocardiogram (ECG) and MHD synchronization. Results: The MHD potential correlates with flow velocities derived from phase contrast MRI. MHD voltages depend on the orientation between B0 and the flow of a conductive fluid. An increase in the interelectrode spacing along the flow increases the MHD potential. In vivo measurement of the MHD effect provides peak voltages of 1.5 mV for surface areas close to the common carotid artery at B0 = 7.0 T. Synchronization of MRI with the cardiac cycle using MHD triggering is feasible. MHD triggered MRA of the carotids at 3.0 T showed an overall image quality and richness of anatomic detail, which is comparable to ECG-triggered MRAs. Conclusion: This feasibility study demonstrates the use of MHD effects for synchronization of MR acquisitions with the cardiac cycle. J. Magn. Reson. Imaging 2012;36:364–372. © 2012 Wiley Periodicals, Inc. Y1 - 2012 U6 - https://doi.org/10.1002/jmri.23634 SN - 1522-2586 VL - 36 IS - 2 SP - 364 EP - 372 PB - Wiley-Liss CY - New York ER -