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2. Intensive heart rhythm monitoring to decrease ischemic stroke and systemic embolism—the Find-AF 2 study—rationale and design

Author

Wachter, Rolf, Gröschel, Klaus, Wasser, Katrin, Uhe, Tobias, Schäbitz, Wolf-Rüdiger, Köhrmann, Martin, Dichgans, Martin, Gröschel, Sonja, Uphaus, Timo, Hahn, Marianne, Zuhorn, Frederic, Wulff, Leonard, Plümer, Jorge, Kok, Lena, Janz, Marcel, Kitsiou, Alkisti, Gehmeyr, Julian, Dabbagh, Alhuda, Huber, Charlotte, Pelz, Johann, Wartenberg, Katja, Michalski, Dominik, Seidel, Mirko, Flissakowski, Oscar, Goschenhofer, Anna, Hussain, Rabia-Basari, Kim, Ina, Kinze, Stephan, Kroneberger, Christian, Lingnau, Michale, Lischewski, Dennis, Muhn, Florian, Rogge, Witold, Schieffer, Miriam, Setayesh-Roonizi, Anuscheh, Sparenberg, Paul, Schertel, Jill Marie, Ringleb, Peter, Purrucker, Jan, Berberich, Anne, Heyse, Miriam, Ungerer, Matthias, Bauer, Gregor, Reichardt, Christine, Etgen, Thorleif, Ebel, Bernhard, Milanković-Eberl, Dragana, Schwarte, Olav, Höcherl, Constanze, Asch, Eric-Manuel, Bojtschuk, Luisa, Frey, Maximilian, Dlouhy, Tomas, Ertl, Michael, Zickler, Philipp Patrick, Beier, Barbara, Braadt, Lino-Dominic, Gabrielyan, Inessa, Kermer, Pawel, Kaste, Matthias, Anter, Ahmed, Stirbulescu, Corina, Meleshchenco, Nataliia, Burgholte, Friederike, Lüers, Claus, Steiner, Thorsten, Cierpinski, Mari-Carmen, Lichti, Bethke, Florian, Bonowski, Lars, Eid, Hassan Abou, Vajda-Medina, Esteban, Probst, Mareike, Essa, Hisham, Frank, Benedikt, Stolte, Benjamin, Milles, Lennart, Soda, Hassan, Hiermann, Erich, Rascher, Renate Weinhardt Alexandra, Stan, Marius, Kääb, Stefan, Kellert, Lars, Dimitriadis, Konstantinos, Kopczak, Anna, Küster, Bettina, Sinner, Moritz, Steiger, Ignaz, Kaffe, Maria, Clauß, Sebastian, Janowitz, Daniel, Thaler, Raffael, Schellinger, Peter, Glahn, Jörg, Schubert, Jan, Jenniges, Simone, Markmann-Boenke, Silke, Putzer, Anne-Sophie, Straeten, Michael Schwarze Vera, Wiemer, Marcus, Kallmünzer, Bernd, Macha, Kosmas, Haupenthal, David, Balk, Stefanie, Kossel, Clara-Sophie, Häusler, Georg, Lehrieder, Dominik, Cidlinsky, Peter, Hametner, Christian, Vogl, Christine, Fischer, Thomas, Huttelmaier, Moritz, Nordbeck, Octavian Maniuc Peter, von Hardenberg, Albrecht, Jünemann, Martin, Braun, Tobias, Viard, Maxime, Gerner, Stefan, Omar, AlHaj, Genau, Sonja, Olbricht, Linus, Wassenberg, Matthias, Langguth, Niklas, Fräbel, Christian, Baumgart, Romy, Kalra, Love-Preet, Diel, Norma, Hoffmann, Frank, Kraft, Andrea, Schönmuth, Bettine, Giebler, Anja, Weber, Lorenz, Grond, Martin, Birringer, Jan, Lichte-Schneider, Sandra, Hütwohl, Daniela, Krause, Lars Udo, Petersen, Martina, Althaus, Katharina, Kirchmeier, Konstantin, Novikova, Liubov, Müller, Susanne, Schellong, Sebastian, Brudzinski, Mirko, Gerk, Ulrich, Palisch, Holger, Heinzel, Frank R., Fett, Jana, Suntha, Avinash, Burian, Katja, Schmitz, Bettina, Gutwinski, Anna, Angermüller, Veronika, Alhammoud, Tameem, Cakiroglu, Hüsniye, Bach, Ullrich, Nabavi, Darius, Offermann, Jens, Crome, Olaf, Dimitrijeski, Boris, Meincke, Carsten, Hamann, Gerhard, Alber, Burkhard, Müller, Robert, Pallesen, Lars-Peder, Pütz, Volker, Hartmann, Christian, Berrouschot, Jörg, Stoll, Anett, Keilitz, Janina, Klunk, Dietrich, Voigt, Roman, Kastrup, Andreas, Schröter, Andreas, Schmucker, Johannes, Pfeilschifter, Waltraud, Krämer, Christoffer, Wiemers, Milena, Simon, Micha, Finke, Alexander, Weiß, Christian, Hobohm, Carsten, Naupold, Katrin, Bley-Renning, Karen, Winter, Sabrina, Poli, Sven, Mengel, Annerose, Poli, Khouloud, Expósito, Alexandra Gómez, Mbroh, Joshua, Tieck, Maria, Rosenkranz, Michael, Boskamp, Stefan, Ritter, Nicolas, Seibel, Lena, Schöps, Christian, Ketzler, Rebecca, Nägele, Herbert, Sydow, Karsten, Kurka, Natalia, Schäfer, Jan Hendrik, Charisse, Daniel, Gruber, Katharina, Kohlhase, Konstantin, Lieschke, Franziska, Operhalski, Felix, Seiler, Alexander, Petzold, Gabor, Bode, Felix Jürgen, Stösser, Sebastian, Meißner, Julius, Ebrahimi, Taraneh, Nordsiek, Julia, Beckonert, Niklas, Weissenborn, Karin, Große, Gerrit Maximilian, Worthmann, Hans, Hennemann, Ann-Katrin, Jochmann, Svenja, Gründahl, Julius, Al-Ayoubi, Jana, Ernst, Johanna, Bähr, Oliver, Gruber, Herbert, Benesch, Sonka, Pollinger, Thomas, Alachkar, Nawar, Busch, Sonia, Butz, Steffi, Forkmann, Mathias, Mahnkopf, Christian, Mischke, Thomas, Schnupp, Steffen, Thomalla, Götz, Deb-Chatterji, Milani, Cheng, Bastian, Gelderblom, Mathias, Hoppe, Julia, Jensen, Märit, Schell, Maximilian, Schlemm, Eckhard, Marquardt, Lars, Kazarians, Haiko, Rheingans, Pia Franziska, Hötzer, Kai, Rose, Dietmar, Neumann-Haefelin, Tobias, Berthel, Jörg, Alijaj, Lirim, Krug, Joachim, Niethammer, Margit, Szöllösi, Géza-Attila, Obermann, Marc, Adochitei, Nicoletta, Strik, Herwig, Lenz, Arne, Steigerwald, Frank, Müller, Jörg, Honermann, Martin, Burgstaller, Marian Christoph, Kollmar, Rainer, Rashid, Maryam, Ganai, Ahmad Ajaz, Ossendorf, Saric, Majda, Tischer, Karl-Heinz, Toluli, Adela, Wollenweber, Frank Arne, Rahban, Laya, Silva, Thais Portugal, Lee, Miri, Grosch, Matthias Julius, Minnerup, Jens, Liman, Jan, Nückel, Martin, Böhm, Magdalena, Weber-Krüger, Mark, Brachmann, Johannes, Laufs, Ulrich, Gelbrich, Götz, Petroff, David, Prettin, Christiane, Schellinger, Peter D., Hamann, Gerhard F., Mende, Meinhard, and Wagner, Marcus

Published
2023
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12. Visceral fat mass dynamics in a 2‐year randomized STrength versus ENdurance training trial in people with obesity.

Author

Lehmann, Stefanie, Retschlag, Ulf, Oberbach, Andreas, Morgenroth, Roland, Linder, Nicolas, Schaudinn, Alexander, Garnov, Nikita, Busse, Harald, Solty, Kilian, Prettin, Christiane, Köppe‐Bauernfeind, Nicole, Flehmig, Gesine, Selig, Lars, Trips, Evelyn, Stumvoll, Michael, Petroff, David, and Blüher, Matthias

Subjects
BODY composition, ADIPOSE tissues, ABDOMINAL adipose tissue, PHYSICAL fitness, BODY mass index, FAT
Abstract

Aim: To compare the effectiveness of strength versus endurance training on reducing visceral fat in individuals with obesity. Materials and Methods: For the STrength versus ENdurance (STEN) 24‐month randomized clinical trial, we assigned 239 participants with abdominal obesity to either strength or endurance training (two to three times a week, 60 min/training session) in addition to standard nutritional counselling to promote a healthy diet. Changes in abdominal visceral adipose tissue (VAT) area quantified by magnetic resonance imaging after 12 months were defined as a primary endpoint. Results: Participants (aged 44 years, 74% women, body mass index: 37 kg/m2, mean VAT volume: 4050 cm3) had an approximately 50% retention rate and a 30% good training programme adherence at 12 months. There was no difference between strength and endurance training in VAT volume dynamics after 12 and 24 months (p =.13). Only in the good adherence group did we find a trend for reduced VAT volume in both training regimens. Independently of the exercise programme, there was a continuous trend for moderate loss of abdominal subcutaneous AT volume, body fat mass, body mass index and improved parameters of insulin sensitivity. Although parameters of physical fitness improved upon both exercise interventions, the dynamics of resting energy expenditure, glucose and lipid metabolism parameters were not different between the intervention groups and did not significantly improve during the 2‐year trial (p >.05). Conclusions: Despite heterogeneous individual training responses, strength and endurance training neither affected VAT volume nor key secondary endpoints differently. [ABSTRACT FROM AUTHOR]

Published
2024
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14. Assessment of hepatic steatosis by controlled attenuation parameter using the M and XL probes: an individual patient data meta-analysis

Author

Petroff, David, Blank, Valentin, Newsome, Philip N, Shalimar, Voican, Cosmin Sebastian, Thiele, Maja, de Lédinghen, Victor, Baumeler, Stephan, Chan, Wah Kheong, Perlemuter, Gabriel, Cardoso, Ana-Carolina, Aggarwal, Sandeep, Sasso, Magali, Eddowes, Peter J, Allison, Michael, Tsochatzis, Emmanuel, Anstee, Quentin M, Sheridan, David, Cobbold, Jeremy F, Naveau, Sylvie, Lupsor-Platon, Monica, Mueller, Sebastian, Krag, Aleksander, Irles-Depe, Marie, Semela, David, Wong, Grace Lai-Hung, Wong, Vincent Wai-Sun, Villela-Nogueira, Cristiane A, Garg, Harshit, Chazouillères, Olivier, Wiegand, Johannes, and Karlas, Thomas

Published
2021
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15. The “VIP-ADHD trial”: Does brain arousal have prognostic value for predicting response to psychostimulants in adult ADHD patients?

Author

Strauß, Maria, Petroff, David, Huang, Jue, Ulke, Christine, Paucke, Madlen, Bogatsch, Holger, Böhme, Pierre, Hoffmann, Knut, Reif, Andreas, Kittel-Schneider, Sarah, Heuser, Isabella, Ahlers, Eike, Gallinat, Juergen, Schöttle, Daniel, Fallgatter, Andreas, Ethofer, Thomas, Unterecker, Stefan, and Hegerl, Ulrich

Published
2021
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16. Individualised positive end-expiratory pressure guided by electrical impedance tomography for robot-assisted laparoscopic radical prostatectomy: a prospective, randomised controlled clinical trial

Author

Girrbach, Felix, Petroff, David, Schulz, Susann, Hempel, Gunther, Lange, Mirko, Klotz, Carolin, Scherz, Stephanie, Giannella-Neto, Antonio, Beda, Alessandro, Jardim-Neto, Alcendino, Stolzenburg, Jens-Uwe, Reske, Andreas W., Wrigge, Hermann, and Simon, Philipp

Published
2020
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20. A Generalized Family of Post-Newtonian Dedekind Ellipsoids

Author

Gürlebeck, Norman and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

We derive a family of Post-Newtonian (PN) Dedekind ellipsoids to first order. They describe non-axially symmetric, homogeneous, and rotating figures of equilibrium. The sequence of the Newtonian Dedekind ellipsoids allows for an axially symmetric limit in which a uniformly rotating Maclaurin spheroid is recovered. However, the approach taken by Chandrasekhar & Elbert (1974) to find the PN Dedekind ellipsoids excludes such a limit. In G\"urlebeck & Petroff (2010), we considered an extension to their work that permits a limit of 1 PN Maclaurin ellipsoids. Here we further detail the sequence and demonstrate that a choice of parameters exists with which the singularity formerly found in Chandrasekhar & Elbert (1974) along the sequence of PN Dedekind ellipsoids is removed., Comment: 23 pages, 17 figures; changes in v2: first paragraph in introduction added, minor changes to agree with published version

Published
2013
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23. The Axisymmetric Case for the Post-Newtonian Dedekind Ellipsoids

Author

Gürlebeck, Norman and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

We consider the post-Newtonian approximation for the Dedekind ellipsoids in the case of axisymmetry. The approach taken by Chandrasekhar & Elbert (1974, 1978) excludes the possibility of finding a uniformly rotating (deformed) spheroid in the axially symmetric limit, though the solution exists at the point of axisymmetry. We consider an extension to their work that permits the possibility of such a limit., Comment: 12 pages, v1: more discussion of comparison to Chandrasekhar's and Elbert's work, modified to agree with published version

Published
2010
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24. Uniformly Rotating Homogeneous Rings in post-Newtonian Gravity

Author

Horatschek, Stefan and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

In this paper uniformly rotating relativistic rings are investigated analytically utilizing two different approximations simultaneously: (1) an expansion about the thin ring limit (the cross-section is small compared with the size of the whole ring) (2) post-Newtonian expansions. The analytic results for rings are compared with numerical solutions., Comment: 12 pages, 7 figures, v1: 2 tables added, agrees with published version

Published
2010
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25. Non-axisymmetric configurations in the post-Newtonian Approximation to General Relativity

Author

Gürlebeck, Norman and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

We use surface adapted ellipsoidal coordinates to obtain a first order post-Newtonian (PN) approximation to Dedekind ellipsoids with the intention of proceeding to higher orders., Comment: 3 pages, no figures, contribution to the 12th Marcel Grossmann Meeting (Paris, July 12 - 18, 2009), submitted to the Conference Proceedings, v2: minor changes

Published
2010

26. Near-infrared spectroscopy and electroencephalography neurofeedback for binge-eating disorder: an exploratory randomized trial.

Author

Hilbert, Anja, Rösch, Sarah Alica, Petroff, David, Prettin, Christiane, Lührs, Michael, Ehlis, Ann-Christin, and Schmidt, Ricarda

Subjects
RESEARCH funding, HEALTH status indicators, BODY mass index, BINGE-eating disorder, ELECTROENCEPHALOGRAPHY, STATISTICAL sampling, PILOT projects, EXECUTIVE function, NEAR infrared spectroscopy, BIOFEEDBACK training, TREATMENT effectiveness, RANDOMIZED controlled trials, DESCRIPTIVE statistics, ANXIETY, RESEARCH, HEALTH behavior, COMPARATIVE studies, CONFIDENCE intervals
Abstract

Background: Binge-eating disorder (BED) co-occurs with neurobehavioral alterations in the processing of disorder-relevant content such as visual food stimuli. Whether neurofeedback (NF) directly targeting them is suited for treatment remains unclear. This study sought to determine feasibility and estimate effects of individualized, functional near-infrared spectroscopy-based real-time NF (rtfNIRS-NF) and high-beta electroencephalography-based NF (EEG-NF), assuming superiority over waitlist (WL). Methods: Single-center, assessor-blinded feasibility study with randomization to rtfNIRS-NF, EEG-NF, or WL and assessments at baseline (t 0), postassessment (t 1), and 6-month follow-up (t 2). NF comprised 12 60-min food-specific rtfNIRS-NF or EEG-NF sessions over 8 weeks. Primary outcome was the binge-eating frequency at t 1 assessed interview-based. Secondary outcomes included feasibility, eating disorder symptoms, mental and physical health, weight management-related behavior, executive functions, and brain activity at t 1 and t 2. Results: In 72 patients (intent-to-treat), the results showed feasibility of NF regarding recruitment, attrition, adherence, compliance, acceptance, and assessment completion. Binge eating improved at t 1 by −8.0 episodes, without superiority of NF v. WL (−0.8 episodes, 95% CI −2.4 to 4.0), but with improved estimates in NF at t 2 relative to t 1. NF was better than WL for food craving, anxiety symptoms, and body mass index, but overall effects were mostly small. Brain activity changes were near zero. Conclusions: The results show feasibility of food-specific rtfNIRS-NF and EEG-NF in BED, and no posttreatment differences v. WL, but possible continued improvement of binge eating. Confirmatory and mechanistic evidence is warranted in a double-blind randomized design with long-term follow-up, considering dose–response relationships and modes of delivery. [ABSTRACT FROM AUTHOR]

Published
2024
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30. A Roche Model for Uniformly Rotating Rings

Author

Horatschek, Stefan and Petroff, David

Subjects
Astrophysics, General Relativity and Quantum Cosmology
Abstract

A Roche model for describing uniformly rotating rings is presented and the results are compared with numerical solutions to the full problem for polytropic rings. In the thin ring limit, the surfaces of constant pressure including the surface of the ring itself are given in analytic terms, even in the mass-shedding case., Comment: 6 pages, 4 figures, v2: minor corrections

Published
2008
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31. Uniformly Rotating Homogeneous and Polytropic Rings in Newtonian Gravity

Author

Petroff, David and Horatschek, Stefan

Subjects
Astrophysics, General Relativity and Quantum Cosmology
Abstract

An analytical method is presented for treating the problem of a uniformly rotating, self-gravitating ring without a central body in Newtonian gravity. The method is based on an expansion about the thin ring limit, where the cross-section of the ring tends to a circle. The iterative scheme developed here is applied to homogeneous rings up to the 20th order and to polytropes with the index n=1 up to the third order. For other polytropic indices no analytic solutions are obtainable, but one can apply the method numerically. However, it is possible to derive a simple formula relating mass to the integrated pressure to leading order without specifying the equation of state. Our results are compared with those generated by highly accurate numerical methods to test their accuracy., Comment: 18 pages, 12 figures. This paper is essentially a combined version of arXiv:0802.0078 and arXiv:0802.0081 and was published in this form. (v2: minor corrections)

Published
2008
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32. Uniformly Rotating Homogeneous Rings in Newtonian Gravity

Author

Horatschek, Stefan and Petroff, David

Subjects
Astrophysics, General Relativity and Quantum Cosmology
Abstract

In this paper, we describe an analytical method for treating uniformly rotating homogeneous rings without a central body in Newtonian gravity. We employ series expansions about the thin ring limit and use the fact that in this limit the cross-section of the ring tends to a circle. The coefficients can in principle be determined up to an arbitrary order. Results are presented here to the 20th order and compared with numerical results., Comment: 10 pages, 5 figures, minor corrections. This paper has be combined with arXiv:0802.0081 and published in MNRAS, see arXiv:0808.2612

Published
2008

33. Negative Komar Masses in Regular Stationary Spacetimes

Author

Ansorg, Marcus and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

A highly accurate multi-domain spectral method is used to study axially symmetric and stationary spacetimes containing a black hole or disc of dust surrounded by a ring of matter. It is shown that the matter ring can affect the properties of the central object drastically. In particular, by virtue of the ring's frame dragging, the so-called Komar mass of the black hole or disc can become negative. A continuous transition from such discs to such black holes can be found., Comment: 3 pages, submitted to the Proceedings of the MGXI Meeting

Published
2007
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35. Slowly Rotating Homogeneous Stars and the Heun Equation

Author

Petroff, David

Subjects
General Relativity and Quantum Cosmology, Mathematical Physics
Abstract

The scheme developed by Hartle for describing slowly rotating bodies in 1967 was applied to the simple model of constant density by Chandrasekhar and Miller in 1974. The pivotal equation one has to solve turns out to be one of Heun's equations. After a brief discussion of this equation and the chances of finding a closed form solution, a quickly converging series solution of it is presented. A comparison with numerical solutions of the full Einstein equations allows one to truncate the series at an order appropriate to the slow rotation approximation. The truncated solution is then used to provide explicit expressions for the metric., Comment: 16 pages, uses document class iopart, v2: minor corrections

Published
2007
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36. Gravitational waves from Extreme Mass Ratio Inspirals in non-pure Kerr spacetimes

Author

Barausse, Enrico, Rezzolla, Luciano, Petroff, David, and Ansorg, Marcus

Subjects
General Relativity and Quantum Cosmology, Astrophysics
Abstract

To investigate the imprint on the gravitational-wave emission from extreme mass-ratio inspirals in non-pure Kerr spacetimes, we have studied the ``kludge'' waveforms generated in highly-accurate, numerically-generated spacetimes containing a black hole and a self-gravitating, homogeneous torus with comparable mass and spin. In order to maximize their impact on the produced waveforms, we have considered tori that are compact, massive and close to the central black hole, investigating under what conditions the LISA experiment could detect their presence. Our results show that for a large portion of the space of parameters the waveforms produced by EMRIs in these black hole-torus systems are indistinguishable from pure-Kerr waveforms. Hence, a ``confusion problem'' will be present for observations carried out over a timescale below or comparable to the dephasing time., Comment: 21 pages, 12 figures. Short discussion on the accuracy of the spacetimes added, typos corrected. Accepted for publication in PRD

Published
2006
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37. Negative Komar Mass of Single Objects in Regular, Asymptotically Flat Spacetimes

Author

Ansorg, Marcus and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

We study two types of axially symmetric, stationary and asymptotically flat spacetimes using highly accurate numerical methods. The one type contains a black hole surrounded by a perfect fluid ring and the other a rigidly rotating disc of dust surrounded by such a ring. Both types of spacetime are regular everywhere (outside of the horizon in the case of the black hole) and fulfil the requirements of the positive energy theorem. However, it is shown that both the black hole and the disc can have negative Komar mass. Furthermore, there exists a continuous transition from discs to black holes even when their Komar masses are negative., Comment: 7 pages, 2 figures, document class iopart. v2: changes made (including title) to coincide with published version

Published
2006
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38. The Parametric Transition of Strange Matter Rings to a Black Hole

Author

Labranche, Hendrick, Petroff, David, and Ansorg, Marcus

Subjects
General Relativity and Quantum Cosmology
Abstract

It is shown numerically that strange matter rings permit a continuous transition to the extreme Kerr black hole. The multipoles as defined by Geroch and Hansen are studied and suggest a universal behaviour for bodies approaching the extreme Kerr solution parametrically. The appearance of a `throat region', a distinctive feature of the extreme Kerr spacetime, is observed. With regard to stability, we verify for a large class of rings, that a particle sitting on the surface of the ring never has enough energy to escape to infinity along a geodesic., Comment: 16 pages, 11 figures, v3: minor changes so as to coincide with published version

Published
2006
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39. The Extreme Distortion of Black Holes due to Matter

Author

Petroff, David and Ansorg, Marcus

Subjects
General Relativity and Quantum Cosmology
Abstract

A highly accurate computer program is used to study axially symmetric and stationary spacetimes containing a Black Hole surrounded by a ring of matter. It is shown that the matter ring affects the properties of the Black Hole drastically. In particular, the absolute value of the ratio of the Black Hole's angular momentum to the square of its mass not only exceeds one, but can be greater than ten thousand (|J|/M^2 > 10^4). Indeed, the numerical evidence suggests that this quantity is unbounded., Comment: 3 pages, 2 figures, v2: minor changes, one reference added

Published
2005

40. Black Holes Surrounded by Uniformly Rotating Rings

Author

Ansorg, Marcus and Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

Highly accurate numerical solutions to the problem of Black Holes surrounded by uniformly rotating rings in axially symmetric, stationary spacetimes are presented. The numerical methods developed to handle the problem are discussed in some detail. Related Newtonian problems are described and numerical results provided, which show that configurations can reach an inner mass-shedding limit as the mass of the central object increases. Exemplary results for the full relativistic problem for rings of constant density are given and the deformation of the event horizon due to the presence of the ring is demonstrated. Finally, we provide an example of a system for which the angular momentum of the central Black Hole divided by the square of its mass exceeds one., Comment: 12 pages, 14 figures, revtex, v4: minor changes, Eq. (17) corrected, corresponds to version in PRD

Published
2005
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42. The Post-Newtonian Maclaurin Spheroids to Arbitrary Order

Author

Petroff, David

Subjects
General Relativity and Quantum Cosmology
Abstract

In this paper, we develop an iterative scheme to enable the explicit calculation of an arbitrary post-Newtonian order for a relativistic body that reduces to the Maclaurin spheroid in the appropriate limit. This scheme allows for an analysis of the structure of the solution in the vicinity of bifurcation points along the Maclaurin sequence. The post-Newtonian expansion is solved explicitly to the fourth order and its accuracy and convergence are studied by comparing it to highly accurate numerical results., Comment: 31 pages, 3 figures

Published
2003
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50. Intensive heart rhythm monitoring to decrease ischemic stroke and systemic embolism—the Find-AF 2 study—rationale and design.

Author

Uhe, Tobias, Wasser, Katrin, Weber-Krüger, Mark, Schäbitz, Wolf-Rüdiger, Köhrmann, Martin, Brachmann, Johannes, Laufs, Ulrich, Dichgans, Martin, Gelbrich, Götz, Petroff, David, Prettin, Christiane, Michalski, Dominik, Kraft, Andrea, Etgen, Thorleif, Schellinger, Peter D., Soda, Hassan, Bethke, Florian, Ertl, Michael, Kallmünzer, Bernd, and Grond, Martin

Abstract

Atrial fibrillation (AF) is one of the most frequent causes of stroke. Several randomized trials have shown that prolonged monitoring increases the detection of AF, but the effect on reducing recurrent cardioembolism, ie, ischemic stroke and systemic embolism, remains unknown. We aim to evaluate whether a risk-adapted, intensified heart rhythm monitoring with consequent guideline conform treatment, which implies initiation of oral anticoagulation (OAC), leads to a reduction of recurrent cardioembolism. Find-AF 2 is a randomized, controlled, open-label parallel multicenter trial with blinded endpoint assessment. 5,200 patients ≥ 60 years of age with symptomatic ischemic stroke within the last 30 days and without known AF will be included at 52 study centers with a specialized stroke unit in Germany. Patients without AF in an additional 24-hour Holter ECG after the qualifying event will be randomized in a 1:1 fashion to either enhanced, prolonged and intensified ECG-monitoring (intervention arm) or standard of care monitoring (control arm). In the intervention arm, patients with a high risk of underlying AF will receive continuous rhythm monitoring using an implantable cardiac monitor (ICM) whereas those without high risk of underlying AF will receive repeated 7-day Holter ECGs. The duration of rhythm monitoring within the control arm is up to the discretion of the participating centers and is allowed for up to 7 days. Patients will be followed for at least 24 months. The primary efficacy endpoint is the time until recurrent ischemic stroke or systemic embolism occur. The Find-AF 2 trial aims to demonstrate that enhanced, prolonged and intensified rhythm monitoring results in a more effective prevention of recurrent ischemic stroke and systemic embolism compared to usual care. [ABSTRACT FROM AUTHOR]

Published
2023
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