Author
Michael Böhm
Other affiliations: University of Rostock, University of Erlangen-Nuremberg
Bio: Michael Böhm is an academic researcher from University of Potsdam. The author has contributed to research in topics: Soliton & Dispersion (optics). The author has an hindex of 15, co-authored 47 publications receiving 863 citations. Previous affiliations of Michael Böhm include University of Rostock & University of Erlangen-Nuremberg.
Papers
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TL;DR: In the human heart, ET(A) and ET(B) receptors coexist; however, only ET( A) receptors are of functional importance; in end-stage CHF, the functional responsiveness of the cardiac ET-receptor system is not altered.
Abstract: Background—In patients with chronic heart failure (CHF), plasma endothelin-1 (ET-1) levels are increased. We studied whether the cardiac ET-receptor system is altered in CHF patients. Methods and Results—We assessed ET-evoked inositol phosphate (IP) formation in slices from right atria and left ventricles from 6 potential heart transplant donors (NFH) and 15 patients with end-stage CHF; in membranes from the same tissues, we studied ET-induced inhibition of isoprenaline- and forskolin-stimulated adenylyl cyclase and ET-receptor density. ET (10−9 to 10−6 mol/L, ET-1 >>> ET-3) increased IP formation in right atria and left ventricles through ETA-receptor stimulation in a concentration-dependent manner; no difference in potency or efficacy between NFH and CHF hearts was observed. ET-1 (10−10 to 10−6 mol/L), via ETA-receptor stimulation, inhibited isoprenaline- and forskolin-stimulated adenylyl cyclase in right atria but not in left ventricles, whereas carbachol inhibited adenylyl cyclase in both tissues; aga...
140 citations
TL;DR: It is concluded that both the reduced titin/MHC ratio and the expression of a structurally different titin form may be involved in the impaired contractile function of the terminally failing human heart.
96 citations
TL;DR: In this paper, a perturbation treatment in several variants of the optical Kerr effect for chirped pulses was used to explain the mechanism responsible for the binding force of the soliton molecules.
Abstract: Temporal optical soliton molecules were recently demonstrated; they potentially allow a further increase of data rates in optical telecommunication We present a theoretical study aimed at an explanation of the mechanism responsible for the binding force To this end we use a perturbation treatment in several variants We find that the well-known soliton interaction as mediated by the optical Kerr effect, when suitably modified for chirped pulses, captures essential features like the existence of a stable equilibrium separation and small-scale oscillations around this point Predictions of these models are compared to numerical simulations
88 citations
TL;DR: In this article, the phase profile of soliton molecules has been measured, and further insight into the mechanism of the binding mechanism is obtained, and the VAMPIRE (very advanced method of phase and intensity retrieval of $E$-fields) method performs reliably.
Abstract: Temporal optical soliton molecules were recently demonstrated; they potentially allow further increase of data rates in optical telecommunication. Their binding mechanism relies on the internal phases, but these have not been experimentally accessible so far. Conventional frequency-resolved optical gating techniques are not suited for measurement of their phase profile: Their algorithms fail to converge due to zeros both in their temporal and their spectral profile. We show that the VAMPIRE (very advanced method of phase and intensity retrieval of $E$-fields) method performs reliably. With VAMPIRE the phase profile of soliton molecules has been measured, and further insight into the mechanism is obtained.
65 citations
TL;DR: In this paper, the authors investigated the dispersion engineering in silicon nitride (SiXNY) waveguides through the optimization of the waveguide transversal dimensions and refractive indices in a multicladding arrangement.
Abstract: Dispersion engineering in silicon nitride (SiXNY) waveguides is investigated through the optimization of the waveguide transversal dimensions and refractive indices in a multicladding arrangement. Ultraflat dispersion of −84.0±0.5 ps/nm/km between 1700 and 2440 nm and 1.5±3 ps/nm/km between 1670 and 2500 nm is numerically demonstrated. It is shown that typical refractive index fluctuations as well as dimension fluctuations during fabrication of the SiXNY waveguides are a limitation for obtaining ultraflat dispersion profiles. Single- and multicladding waveguides are fabricated and their dispersion profiles measured (over nearly 1000 nm) using a low-coherence frequency domain interferometric technique. By appropriate thickness optimization, the zero-dispersion wavelength is tuned over a large spectral range in single- and multicladding waveguides with small refractive index contrast (3%). A flat dispersion profile with ±3.2 ps/nm/km variation over 500 nm is obtained in a multicladding waveguide fabricated with a refractive index contrast of 37%. Finally, we generate a nearly three-octave supercontinuum in this dispersion flattened multicladding SiXNY waveguide.
59 citations
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01 Jan 2005
TL;DR: The Monthly Notices as mentioned in this paper is one of the three largest general primary astronomical research publications in the world, published by the Royal Astronomical Society (RAE), and it is the most widely cited journal in astronomy.
Abstract: Monthly Notices is one of the three largest general primary astronomical research publications. It is an international journal, published by the Royal Astronomical Society. This article 1 describes its publication policy and practice.
2,091 citations
TL;DR: In this paper, the design requirements of SESAM's for stable pulse generation in both the mode-locked and Q-switched regime were reviewed, and the combination of device structure and material parameters provided sufficient design freedom to choose key parameters such as recovery time, saturation intensity, and saturation fluence.
Abstract: Intracavity semiconductor saturable absorber mirrors (SESAM's) offer unique and exciting possibilities for passively pulsed solid-state laser systems, extending from Q-switched pulses in the nanosecond and picosecond regime to mode-locked pulses from 10's of picoseconds to sub-10 fs. This paper reviews the design requirements of SESAM's for stable pulse generation in both the mode-locked and Q-switched regime. The combination of device structure and material parameters for SESAM's provide sufficient design freedom to choose key parameters such as recovery time, saturation intensity, and saturation fluence, in a compact structure with low insertion loss. We have been able to demonstrate, for example, passive modelocking (with no Q-switching) using an intracavity saturable absorber in solid-state lasers with long upper state lifetimes (e.g., 1-/spl mu/m neodymium transitions), Kerr lens modelocking assisted with pulsewidths as short as 6.5 fs from a Ti:sapphire laser-the shortest pulses ever produced directly out of a laser without any external pulse compression, and passive Q-switching with pulses as short as 56 ps-the shortest pulses ever produced directly from a Q-switched solid-state laser. Diode-pumping of such lasers is leading to practical, real-world ultrafast sources, and we will review results on diode-pumped Cr:LiSAF, Nd:glass, Yb:YAG, Nd:YAG, Nd:YLF, Nd:LSB, and Nd:YVO/sub 4/.
1,866 citations
TL;DR: This review focuses only on permanent modifications in relation to clinical dysfunction in cardiac remodeling secondary to myocardial infarction and/or arterial hypertension and includes a special section on the senescent heart, since CR is mainly a disease of the elderly.
Abstract: Swynghedauw, Bernard. Molecular Mechanisms of Myocardial Remodeling. Physiol. Rev. 79: 215–262, 1999. — “Remodeling” implies changes that result in rearrangement of normally existing structures. Th...
1,489 citations
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TL;DR: In this paper, the amount of water outgassed from Mars by impact erosion and hydrodynamic escape is estimated to be between 6 to 160 m. The two sets of estimates may be reconciled if early in its history, Mars lost part of its atmosphere.
Abstract: Estimates of the amount of water outgassed from Mars, based on the composition of the atmosphere, range from 6 to 160 m, as compared with 3 km for the Earth. In contrast, large flood features, valley networks, and several indicators of ground ice suggest that at least 500 m of water have outgassed. The two sets of estimates may be reconciled if early in its history, Mars lost part of its atmosphere by impact erosion and hydrodynamic escape.
910 citations
TL;DR: In this paper, Belitz et al. presented a survey of the state-of-the-art in condensed-matter physics, focusing on the following papers: Condensed Matter Physics (Theoretical) J. IGNACIO CIRAC, Max-Planck-Institut für Quantenoptik Quantum Information RAYMOND E. GOLDSTEIN, University of Cambridge Biological Physics ARTHUR F. HEBARD and DAVID D. KAMIEN.
Abstract: Associate DIETRICH BELITZ, University of Oregon Editors: Condensed Matter Physics (Theoretical) J. IGNACIO CIRAC, Max-Planck-Institut für Quantenoptik Quantum Information RAYMOND E. GOLDSTEIN, University of Cambridge Biological Physics ARTHUR F. HEBARD, University of Florida Condensed Matter Physics (Experimental) RANDALL D. KAMIEN, University of Pennsylvania Soft Condensed Matter DANIEL KLEPPNER, Massachusetts Institute of Technology Atomic, Molecular, and Optical Physics (Experimental) PAUL G. LANGACKER, Institute for Advanced Study, Princeton University Particle Physics (Theoretical) VERA LÜTH, Stanford University Particle Physics (Experimental) DAVID D. MEYERHOFER, University of Rochester Physics of Plasmas and Matter at High-Energy Density WITOLD NAZAREWICZ, University of Tennessee, Oak Ridge National Laboratory Nuclear Physics JOHN H. SCHWARZ, California Institute of Technology Mathematical Physics FRIEDRICH-KARL THIELEMANN, Universität Basel Astrophysics Senior Assistant Editor: DEBBIE BRODBAR, APS Editorial Office American Physical Society
774 citations