@article{ThielRomanoKurths2006,
  author    = {Thiel, Marco and Romano, Maria Carmen and Kurths, J{\"u}rgen},
  title     = {Spurious structures in recurrence plots induced by embedding},
  doi       = {10.1007/s11071-006-2010-9},
  year      = {2006},
  abstract  = {In this paper we show that delay embedding produces spurious structures in a recurrence plot (RP) that are not present in the real attractor. We analyze typical sets of simulated data, such as white noise and data from the chaotic Rossler system to show the relevance of this effect. In the second part of the paper we show that the second order Renyi entropy and the correlation dimension are dynamical invariants that can be estimated from Recurrence Plots with arbitrary embedding dimension and delay},
  language  = {en}
}
@article{TinoCacciapuotiBongsetal.2007,
  author    = {Tino, G. M. and Cacciapuoti, L. and Bongs, K. and Bord{\´e}, Ch. J. and Bouyer, P. and Dittus, H. and Ertmer, W. and G{\"o}rlitz, A. and Inguscio, M. and Landragin, A. and Lemonde, P. and L{\"a}mmerzahl, C. and Peters, A. and Rasel, E. and Reichel, J. and Salomon, C. and Schiller, S. and Schleich, W. and Sengstock, K. and Sterr, U. and Wilkens, Martin},
  title     = {Atom interferometers and optical atomic clocks : new quantum sensors for fundamental physics experiments in space},
  year      = {2007},
  abstract  = {We present projects for future space missions using new quantum devices based on ultracold atoms. They will enable fundamental physics experiments testing quantum physics, physics beyond the standard model of fundamental particles and interactions, special relativity, gravitation and general relativity.},
  language  = {en}
}
@article{GoldobinPikovskij2006,
  author    = {Goldobin, Denis S. and Pikovskij, Arkadij},
  title     = {Effects of delayed feedback on Kuramoto transition},
  issn      = {0375-9687},
  doi       = {10.1143/PTPS.161.43},
  year      = {2006},
  abstract  = {We develop a weakly nonlinear theory of the Kuramoto transition in an ensemble of globally coupled oscillators in presence of additional time-delayed coupling terms. We show that a linear delayed feedback not only controls the transition point, but effectively changes the nonlinear terms near the transition. A purely nonlinear delayed coupling does not effect the transition point, but can reduce or enhance the amplitude of collective oscillations},
  language  = {en}
}
@article{GarnierLaschewskyStorsberg2006,
  author    = {Garnier, Sebastien and Laschewsky, Andr{\´e} and Storsberg, J},
  title     = {Polymeric surfactants : novel agents with exceptional properties},
  issn      = {0932-3414},
  year      = {2006},
  abstract  = {This article presents recent progress in the field of polymeric surfactants made of permanently amphiphilic block copolymers or of stimulus-sensitive ones. We highlight key points in the design of amphiphilic macromolecules, to yield polymer surfactants with tailor-made properties, as well as recently developed and still challenging application fields for this new class of surfactants. The efficiency boosting of amphiphilic block copolymers as co-surfactants in microemulsions is discussed, as are surface modification by polymer surfactants, and stabilization of dispersions. Moreover, the use of block copolymers in nanosciences is presented, for instance as a tool for nanomaterial fabrication, or for biomedical and cosmetic applications in bio-nanotechnology. Finally, self-assembly and applications of some newly developed "exotic" amphiphilic block copolymer structures as new surface-active materials will be highlighted},
  language  = {en}
}
@article{ZhangHayerAlSutietal.2006,
  author    = {Zhang, Ning and Hayer, Anna and Al-Suti, Mohammed K. and Al-Belushi, Rayya A. and Khan, Muhammad S. and K{\"o}hler, Anna},
  title     = {The effect of delocalization on the exchange energy in meta- and para-linked Pt-containing carbazole polymers and monomers},
  doi       = {10.1063/1.2200351},
  year      = {2006},
  abstract  = {A series of novel platinum-containing carbazole monomers and polymers was synthesized and fully characterized by UV-VIS absorption, luminescence, and photoinduced absorption studies. In these compounds, a carbazole unit is incorporated into the main chain via either a para- or a meta-linkage. We discuss the effects of linkage and polymerization on the energy levels of S-1, T-1, and T-n. The S-1-T-1 splitting observed for the meta-linked monomer (0.4 eV) is only half of that in the para-linked monomer (0.8 eV). Upon polymerization, the exchange energy in the para- linked compound reduces, yet still remains larger than in the meta-linked polymer. We attribute the difference in exchange energy to the difference in wave function overlap between electron and hole in these compounds. (c) 2006 American Institute of Physics},
  language  = {en}
}
@article{BoccalettiHwangChavezetal.2006,
  author    = {Boccaletti, Stefano and Hwang, Dong-Uk and Chavez, Mario and Amann, Andreas and Kurths, J{\"u}rgen and Pecora, Louis M.},
  title     = {Synchronization in dynamical networks : evolution along commutative graphs},
  issn      = {1539-3755},
  doi       = {10.1103/Physreve.74.016102},
  year      = {2006},
  abstract  = {Starting from an initial wiring of connections, we show that the synchronizability of a network can be significantly improved by evolving the graph along a time dependent connectivity matrix. We consider the case of connectivity matrices that commute at all times, and compare several approaches to engineer the corresponding commutative graphs. In particular, we show that synchronization in a dynamical network can be achieved even in the case in which each individual commutative graphs does not give rise to synchronized behavior},
  language  = {en}
}
@article{GoldobinPikovskij2006,
  author    = {Goldobin, Denis S. and Pikovskij, Arkadij},
  title     = {Antireliability of noise-driven neurons},
  issn      = {1539-3755},
  doi       = {10.1103/Physreve.73.061906},
  year      = {2006},
  abstract  = {We demonstrate, within the framework of the FitzHugh-Nagumo model, that a firing neuron can respond to a noisy driving in a nonreliable manner: the same Gaussian white noise acting on identical neurons evokes different patterns of spikes. The effect is characterized via calculations of the Lyapunov exponent and the event synchronization correlations. We construct a theory that explains the antireliability as a combined effect of a high sensitivity to noise of some stages of the dynamics and nonisochronicity of oscillations. Geometrically, the antireliability is described by a random noninvertible one-dimensional map},
  language  = {en}
}
@article{AnishchenkoNikolaevKurths2006,
  author    = {Anishchenko, Vadim S. and Nikolaev, S and Kurths, J{\"u}rgen},
  title     = {Winding number locking on a two-dimensional torus : synchronization of quasiperiodic motions},
  issn      = {1539-3755},
  doi       = {10.1103/Physreve.73.056202},
  year      = {2006},
  abstract  = {We propose a new autonomous dynamical system of dimension N=4 that demonstrates the regime of stable two- frequency motions and period-doubling bifurcations of a two-dimensional torus. It is shown that the period-doubling bifurcation of the two-dimensional torus is not followed by the resonance phenomenon, and the two-dimensional ergodic torus undergoes a period-doubling bifurcation. The interaction of two generators is also analyzed. The phenomenon of external and mutual synchronization of two-frequency oscillations is observed, for which winding number locking on a two- dimensional torus takes place},
  language  = {en}
}
@article{NolteMeineckeZieheetal.2006,
  author    = {Nolte, Guido and Meinecke, Frank C. and Ziehe, Andreas and M{\"u}ller, Klaus-Robert},
  title     = {Identifying interactions in mixed and noisy complex systems},
  doi       = {10.1103/Physreve.73.051913},
  year      = {2006},
  abstract  = {We present a technique that identifies truly interacting subsystems of a complex system from multichannel data if the recordings are an unknown linear and instantaneous mixture of the true sources. The method is valid for arbitrary noise structure. For this, a blind source separation technique is proposed that diagonalizes antisymmetrized cross- correlation or cross-spectral matrices. The resulting decomposition finds truly interacting subsystems blindly and suppresses any spurious interaction stemming from the mixture. The usefulness of this interacting source analysis is demonstrated in simulations and for real electroencephalography data},
  language  = {en}
}
@article{RaabWesselSchirdewanetal.2006,
  author    = {Raab, Corinna and Wessel, Niels and Schirdewan, Alexander and Kurths, J{\"u}rgen},
  title     = {Large-scale dimension densities for heart rate variability analysis},
  issn      = {1539-3755},
  doi       = {10.1103/Physreve.73.041907},
  year      = {2006},
  abstract  = {In this work, we reanalyze the heart rate variability (HRV) data from the 2002 Computers in Cardiology (CiC) Challenge using the concept of large-scale dimension densities and additionally apply this technique to data of healthy persons and of patients with cardiac diseases. The large-scale dimension density (LASDID) is estimated from the time series using a normalized Grassberger-Procaccia algorithm, which leads to a suitable correction of systematic errors produced by boundary effects in the rather large scales of a system. This way, it is possible to analyze rather short, nonstationary, and unfiltered data, such as HRV. Moreover, this method allows us to analyze short parts of the data and to look for differences between day and night. The circadian changes in the dimension density enable us to distinguish almost completely between real data and computer-generated data from the CiC 2002 challenge using only one parameter. In the second part we analyzed the data of 15 patients with atrial fibrillation (AF), 15 patients with congestive heart failure (CHF), 15 elderly healthy subjects (EH), as well as 18 young and healthy persons (YH). With our method we are able to separate completely the AF (rho(mu)(ls)=0.97 +/- 0.02) group from the others and, especially during daytime, the CHF patients show significant differences from the young and elderly healthy volunteers (CHF, 0.65 +/- 0.13; EH, 0.54 +/- 0.05; YH, 0.57 +/- 0.05; p < 0.05 for both comparisons). Moreover, for the CHF patients we find no circadian changes in rho(mu)(ls) (day, 0.65 +/- 0.13; night, 0.66 +/- 0.12; n.s.) in contrast to healthy controls (day, 0.54 +/- 0.05; night, 0.61 +/- 0.05; p=0.002). Correlation analysis showed no statistical significant relation between standard HRV and circadian LASDID, demonstrating a possibly independent application of our method for clinical risk stratification},
  language  = {en}
}