@article{GvaramadzeKniazevHamannetal.2010,
  author    = {Gvaramadze, Vasily V. and Kniazev, Alexei Y. and Hamann, Wolf-Rainer and Berdnikov, Leonid N. and Fabrika, Sergei Nikolaevich and Valeev, Azamat F.},
  title     = {A new Wolf-Rayet star and its circumstellar nebula in Aquila},
  issn      = {0035-8711},
  doi       = {10.1111/j.1365-2966.2009.16126.x},
  year      = {2010},
  abstract  = {We report the discovery of a new Wolf-Rayet star in Aquila via detection of its circumstellar nebula (reminiscent of ring nebulae associated with late WN stars) using the Spitzer Space Telescope archival data. Our spectroscopic follow-up of the central point source associated with the nebula showed that it is a WN7h star (we named it WR121b). We analysed the spectrum of WR 121b by using the Potsdam Wolf-Rayet model atmospheres, obtaining a stellar temperature of similar or equal to 50 kK. The stellar wind composition is dominated by helium with similar to 20 per cent of hydrogen. The stellar spectrum is highly reddened [E(B - V) = 2.85 mag]. Adopting an absolute magnitude of M-v = 5.7, the star has a luminosity of log L/L-circle dot = 5.75 and a mass-loss rate of 10(-4.7)M(circle dot)yr(-1), and resides at a distance of 6.3 kpc. We searched for a possible parent cluster of WR 121b and found that this star is located at similar or equal to 1 degrees from the young star cluster embedded in the giant HII region W43 (containing a WN7+a/OB? star - WR121a). We also discovered a bow shock around the O9.5III star ALS 9956, located at similar or equal to 0 degrees.5 from the cluster. We discuss the possibility that WR121b and ALS 9956 are runaway stars ejected from the cluster in W43.},
  language  = {en}
}
@article{CramerEisert2010,
  author    = {Cramer, Marcus and Eisert, Jens},
  title     = {A quantum central limit theorem for non-equilibrium systems : exact local relaxation of correlated states},
  issn      = {1367-2630},
  doi       = {10.1088/1367-2630/12/5/055020},
  year      = {2010},
  abstract  = {We prove that quantum many-body systems on a one-dimensional lattice locally relax to Gaussian states under non- equilibrium dynamics generated by a bosonic quadratic Hamiltonian. This is true for a large class of initial states-pure or mixed-which have to satisfy merely weak conditions concerning the decay of correlations. The considered setting is a proven instance of a situation where dynamically evolving closed quantum systems locally appear as if they had truly relaxed, to maximum entropy states for fixed second moments. This furthers the understanding of relaxation in suddenly quenched quantum many-body systems. The proof features a non-commutative central limit theorem for non-i.i.d. random variables, showing convergence to Gaussian characteristic functions, giving rise to trace-norm closeness. We briefly link our findings to the ideas of typicality and concentration of measure.},
  language  = {en}
}
@article{GrossMuellerColbecketal.2010,
  author    = {Gross, David and Mueller, Markus and Colbeck, Roger and Dahlsten, Oscar C. O.},
  title     = {All reversible dynamics in maximally nonlocal theories are trivial},
  issn      = {0031-9007},
  doi       = {10.1103/Physrevlett.104.080402},
  year      = {2010},
  abstract  = {A remarkable feature of quantum theory is nonlocality ( Bell inequality violations). However, quantum correlations are not maximally nonlocal, and it is natural to ask whether there are compelling reasons for rejecting theories in which stronger violations are possible. To shed light on this question, we consider post-quantum theories in which maximally nonlocal states ( nonlocal boxes) occur. We show that reversible transformations in such theories are trivial: they consist solely of local operations and permutations of systems. In particular, no correlations can be created; nonlocal boxes cannot be prepared from product states and classical computers can efficiently simulate all such processes.},
  language  = {en}
}
@article{CuzziBurnsCharnozetal.2010,
  author    = {Cuzzi, Jeff N. and Burns, Joseph A. and Charnoz, S{\´e}bastien and Clark, Roger N. and Colwell, Josh E. and Dones, Luke and Esposito, Larry W. and Filacchione, Gianrico and French, Richard G. and Hedman, Matthew M. and Kempf, Sascha and Marouf, Essam A. and Murray, Carl D. and Nicholson, Phillip D. and Porco, Carolyn C. and Schmidt, J{\"u}rgen and Showalter, Mark R. and Spilker, Linda J. and Spitale, Joseph N. and Srama, Ralf and Sremcević, Miodrag and Tiscareno, Matthew Steven and Weiss, John},
  title     = {An evolving view of Saturn's dynamic rings},
  issn      = {0036-8075},
  doi       = {10.1126/science.1179118},
  year      = {2010},
  abstract  = {We review our understanding of Saturn's rings after nearly 6 years of observations by the Cassini spacecraft. Saturn's rings are composed mostly of water ice but also contain an undetermined reddish contaminant. The rings exhibit a range of structure across many spatial scales; some of this involves the interplay of the fluid nature and the self-gravity of innumerable orbiting centimeter- to meter-sized particles, and the effects of several peripheral and embedded moonlets, but much remains unexplained. A few aspects of ring structure change on time scales as short as days. It remains unclear whether the vigorous evolutionary processes to which the rings are subject imply a much younger age than that of the solar system. Processes on view at Saturn have parallels in circumstellar disks.},
  language  = {en}
}
@article{BordyugovFischerEngeletal.2010,
  author    = {Bordyugov, Grigory and Fischer, Nils and Engel, Harald and Manz, Niklas and Steinbock, Oliver},
  title     = {Anomalous dispersion in the Belousov-Zhabotinsky reaction : experiments and modeling},
  issn      = {0167-2789},
  doi       = {10.1016/j.physd.2009.10.022},
  year      = {2010},
  abstract  = {We report results on dispersion relations and instabilities of traveling waves in excitable systems. Experiments employ solutions of the 1,4-cyclohexanedione Belousov-Zhabotinsky reaction confined to thin capillary tubes which create a pseudo-one-dimensional system. Theoretical analyses focus on a three-variable reaction-diffusion model that is known to reproduce qualitatively many of the experimentally observed dynamics. Using continuation methods, we show that the transition from normal, monotonic to anomalous, single-overshoot dispersion curves is due to an orbit flip bifurcation of the solitary pulse homoclinics. In the case of "wave stacking", this anomaly induces attractive pulse interaction, slow solitary pulses, and faster wave trains. For "wave merging", wave trains break up in the wake of the slow solitary pulse due to an instability of wave trains at small wavelength. A third case, "wave tracking" is characterized by the non-existence of solitary waves but existence of periodic wave trains. The corresponding dispersion curve is a closed curve covering a finite band of wavelengths.},
  language  = {en}
}
@article{VladkovaKoynovaTeuchneretal.2010,
  author    = {Vladkova, Radka and Koynova, Rumiana and Teuchner, Klaus and Tenchov, Boris},
  title     = {Bilayer structural destabilization by low amounts of chlorophyll a},
  issn      = {0005-2736},
  doi       = {10.1016/j.bbamem.2010.05.008},
  year      = {2010},
  abstract  = {The present study shows that small admixtures of one chlorophyll a (Chla) molecule per several hundred lipid molecules have strong destabilizing effect on lipid bilayers. This effect is clearly displayed in the properties of the L-alpha-H-II transformations and results from a Chla preference for the H-II relative to the L-alpha phase. Chla disfavors the lamellar liquid crystalline phase L-alpha and induces its replacement with inverted hexagonal phase H-II, as is consistently demonstrated by DSC and X-ray diffraction measurements on phosphatidylethanolamine (PE) dispersions. Chla lowers the L-alpha-H-II transition temperature (42 degrees C) of the fully hydrated dipalmitoleoyl PE (DPoPE) by similar to 8 degrees C and similar to 17 degrees C at Chla/DPoPE molar ratios of 1:500 and 1:100, respectively. Similar Chla effect was recorded also for dielaidoyl PE dispersions. The lowering of the transition temperature and the accompanying significant loss of transition cooperativity reflect the Chla repartitioning and preference for the H-II phase. The reduction of the H-II phase lattice constant in the presence of Chla is an indication that Chla favors v phase formation by decreasing the radius of spontaneous monolayer curvature, and not by filling up the interstitial spaces between the H-II phase cylinders. The observed Chla preference for H-II phase and the substantial bilayer destabilization in the vicinity of a bilayer-to-nonbilayer phase transformation caused by low Chla concentrations can be of interest as a potential regulatory or membrane-damaging factor.},
  language  = {en}
}
@article{SteyrleuthnerSchubertJaiseretal.2010,
  author    = {Steyrleuthner, Robert and Schubert, Marcel and Jaiser, Frank and Blakesley, James C. and Chen, Zhihua and Facchetti, Antonio and Neher, Dieter},
  title     = {Bulk electron transport and charge injection in a high mobility n-type semiconducting polymer},
  issn      = {0935-9648},
  doi       = {10.1002/adma.201000232},
  year      = {2010},
  abstract  = {Bulk electron transport in a high mobility n-type polymer is studied by time-of-flight photocurrent measurements and electron-only devices. Bulk electron mobilities of similar to 5 x 10(-3) cm(2)/Vs are obtained. The analysis of the electron currents suggests the presence of an injection barrier for all conventionally used low workfunction cathodes.},
  language  = {en}
}
@article{SenthilkumarKurths2010,
  author    = {Senthilkumar, Dharmapuri Vijayan and Kurths, J{\"u}rgen},
  title     = {Characteristics and synchronization of time-delay systems driven by a common noise},
  issn      = {1951-6355},
  doi       = {10.1140/epjst/e2010-01273-4},
  year      = {2010},
  abstract  = {We investigate the characteristics of time-delay systems in the presence of Gaussian noise. We show that the delay time embedded in the time series of time-delay system with constant delay cannot be estimated in the presence noise for appropriate values of noise intensity thereby forbidding any possibility of phase space reconstruction. We also demonstrate the existence of complete synchronization between two independent identical time-delay systems driven by a common noise without explicitly establishing any external coupling between them.},
  language  = {en}
}
@article{BangeSchubertNeher2010,
  author    = {Bange, Sebastian and Schubert, Marcel and Neher, Dieter},
  title     = {Charge mobility determination by current extraction under linear increasing voltages : case of nonequilibrium charges and field-dependent mobilities},
  issn      = {1098-0121},
  doi       = {10.1103/Physrevb.81.035209},
  year      = {2010},
  abstract  = {The method of current extraction under linear increasing voltages (CELIV) allows for the simultaneous determination of charge mobilities and charge densities directly in thin-film geometries as used in organic photovoltaic (OPV) cells. It has been specifically applied to investigate the interrelation of microstructure and charge-transport properties in such systems. Numerical and analytical calculations presented in this work show that the evaluation of CELIV transients with the commonly used analysis scheme is error prone once charge recombination and, possibly, field- dependent charge mobilities are taken into account. The most important effects are an apparent time dependence of charge mobilities and errors in the determined field dependencies. Our results implicate that reports on time-dependent mobility relaxation in OPV materials obtained by the CELIV technique should be carefully revisited and confirmed by other measurement methods.},
  language  = {en}
}
@article{EisertCramerPlenio2010,
  author    = {Eisert, Jens and Cramer, Marcus and Plenio, Martin B.},
  title     = {Colloquium : area laws for the entanglement entropy},
  issn      = {0034-6861},
  doi       = {10.1103/RevModPhys.82.277},
  year      = {2010},
  abstract  = {Physical interactions in quantum many-body systems are typically local: Individual constituents interact mainly with their few nearest neighbors. This locality of interactions is inherited by a decay of correlation functions, but also reflected by scaling laws of a quite profound quantity: the entanglement entropy of ground states. This entropy of the reduced state of a subregion often merely grows like the boundary area of the subregion, and not like its volume, in sharp contrast with an expected extensive behavior. Such "area laws" for the entanglement entropy and related quantities have received considerable attention in recent years. They emerge in several seemingly unrelated fields, in the context of black hole physics, quantum information science, and quantum many-body physics where they have important implications on the numerical simulation of lattice models. In this Colloquium the current status of area laws in these fields is reviewed. Center stage is taken by rigorous results on lattice models in one and higher spatial dimensions. The differences and similarities between bosonic and fermionic models are stressed, area laws are related to the velocity of information propagation in quantum lattice models, and disordered systems, nonequilibrium situations, and topological entanglement entropies are discussed. These questions are considered in classical and quantum systems, in their ground and thermal states, for a variety of correlation measures. A significant proportion is devoted to the clear and quantitative connection between the entanglement content of states and the possibility of their efficient numerical simulation. Matrix-product states, higher-dimensional analogs, and variational sets from entanglement renormalization are also discussed and the paper is concluded by highlighting the implications of area laws on quantifying the effective degrees of freedom that need to be considered in simulations of quantum states.},
  language  = {en}
}
@article{BaibolatovRosenblumZhanabaevetal.2010,
  author    = {Baibolatov, Yernur and Rosenblum, Michael and Zhanabaev, Zeinulla Zh. and Pikovskij, Arkadij},
  title     = {Complex dynamics of an oscillator ensemble with uniformly distributed natural frequencies and global nonlinear coupling},
  issn      = {1539-3755},
  doi       = {10.1103/Physreve.82.016212},
  year      = {2010},
  abstract  = {We consider large populations of phase oscillators with global nonlinear coupling. For identical oscillators such populations are known to demonstrate a transition from completely synchronized state to the state of self-organized quasiperiodicity. In this state phases of all units differ, yet the population is not completely incoherent but produces a nonzero mean field; the frequency of the latter differs from the frequency of individual units. Here we analyze the dynamics of such populations in case of uniformly distributed natural frequencies. We demonstrate numerically and describe theoretically (i) states of complete synchrony, (ii) regimes with coexistence of a synchronous cluster and a drifting subpopulation, and (iii) self-organized quasiperiodic states with nonzero mean field and all oscillators drifting with respect to it. We analyze transitions between different states with the increase of the coupling strength; in particular we show that the mean field arises via a discontinuous transition. For a further illustration we compare the results for the nonlinear model with those for the Kuramoto-Sakaguchi model.},
  language  = {en}
}
@article{ChenShiauTsengetal.2010,
  author    = {Chen, Jin-Long and Shiau, Yuo-Hsien and Tseng, Yin-Jiun and Chiu, Hung-Wen and Hsiao, Tzu-Chien and Wessel, Niels and Kurths, J{\"u}rgen and Chu, Woei-Chyn},
  title     = {Concurrent sympathetic activation and vagal withdrawal in hyperthyroidism : evidence from detrended fluctuation analysis of heart rate variability},
  issn      = {0378-4371},
  doi       = {10.1016/j.physa.2009.12.062},
  year      = {2010},
  abstract  = {Despite many previous Studies on the association between hyperthyroidism and the hyperadrenergic state, controversies still exist. Detrended fluctuation analysis (DFA) is a well recognized method in the nonlinear analysis of heart rate variability (HRV), and it has physiological significance related to the autonomic nervous system. In particular, an increased short-term scaling exponent alpha 1 calculated from DFA is associated with both increased sympathetic activity and decreased vagal activity. No study has investigated the DFA of HRV in hyperthyroidism. This study was designed to assess the sympathovagal balance in hyperthyroidism. We performed the DFA along with the linear analysis of HRV in 36 hyperthyroid Graves' disease patients (32 females and 4 males; age 30 +/- 1 years, means +/- SE) and 36 normal controls matched by sex, age and body mass index. Compared with the normal controls, the hyperthyroid patients revealed a significant increase (P < 0.001) in alpha 1 (hyperthyroid 1.28 +/- 0.04 versus control 0.91 +/- 0.02), long-term scaling exponent alpha 2 (1.05 +/- 0.02 versus 0.90 +/- 0.01), overall scaling exponent alpha (1.11 +/- 0.02 versus 0.89 +/- 0.01), low frequency power in normalized units (LF\%) and the ratio of low frequency power to high frequency power (LF/HF); and a significant decrease (P < 0.001) in the standard deviation of the R-R intervals (SDNN) and high frequency power (HF). In conclusion, hyperthyroidism is characterized by concurrent sympathetic activation and vagal withdrawal. This sympathovagal imbalance state in hyperthyroidism helps to explain the higher prevalence of atrial fibrillation and exercise intolerance among hyperthyroid patients.},
  language  = {en}
}
@article{StichBeta2010,
  author    = {Stich, Michael and Beta, Carsten},
  title     = {Control of pattern formation by time-delay feedback with global and local contributions},
  issn      = {0167-2789},
  doi       = {10.1016/j.physd.2010.05.001},
  year      = {2010},
  abstract  = {We consider the suppression of spatiotemporal chaos in the complex Ginzburg-Landau equation by a combined global and local time-delay feedback. Feedback terms are implemented as a control scheme, i.e., they are proportional to the difference between the time-delayed state of the system and its current state. We perform a linear stability analysis of uniform oscillations with respect to space-dependent perturbations and compare with numerical simulations. Similarly, for the fixed-point solution that corresponds to amplitude death in the spatially extended system, a linear stability analysis with respect to space-dependent perturbations is performed and complemented by numerical simulations.},
  language  = {en}
}
@article{SchwabedalPikovskij2010,
  author    = {Schwabedal, Justus T. C. and Pikovskij, Arkadij},
  title     = {Effective phase description of noise-perturbed and noise-induced oscillations},
  issn      = {1951-6355},
  doi       = {10.1140/epjst/e2010-01271-6},
  year      = {2010},
  abstract  = {An effective dynamical description of a general class of stochastic phase oscillators is presented. For this, the effective phase velocity is defined either by the stochastic phase oscillators invariant probability density or its first passage times. Using the first approach the effective phase exhibits the correct frequency and invariant distribution density, whereas the second approach models the proper phase resetting curve. The discrepancy of the effective models is most pronounced for noise-induced oscillations and is related to non-monotonicity of the stochastic phase variable due to fluctuations.},
  language  = {en}
}
@article{SchwabedalPikovskij2010,
  author    = {Schwabedal, Justus T. C. and Pikovskij, Arkadij},
  title     = {Effective phase dynamics of noise-induced oscillations in excitable systems},
  issn      = {1539-3755},
  doi       = {10.1103/Physreve.81.046218},
  year      = {2010},
  abstract  = {We develop an effective description of noise-induced oscillations based on deterministic phase dynamics. The phase equation is constructed to exhibit correct frequency and distribution density of noise-induced oscillations. In the simplest one-dimensional case the effective phase equation is obtained analytically, whereas for more complex situations a simple method of data processing is suggested. As an application an effective coupling function is constructed that quantitatively describes periodically forced noise-induced oscillations.},
  language  = {en}
}
@article{SkoczowskyJechowMenzeletal.2010,
  author    = {Skoczowsky, Danilo and Jechow, Andreas and Menzel, Ralf and Paschke, Katrin and Erbert, G{\"o}tz},
  title     = {Efficient second-harmonic generation using a semiconductor tapered amplifier in a coupled ring-resonator geometry},
  issn      = {0146-9592},
  doi       = {10.1364/OL.35.000232},
  year      = {2010},
  abstract  = {A new approach for efficient second-harmonic generation using diode lasers is presented. The experimental setup is based on a tapered amplifier operated in a ring resonator that is coupled to a miniaturized enhancement ring resonator containing a periodically poled lithium niobate crystal. Frequency locking of the diode laser emission to the resonance frequency of the enhancement cavity is realized purely optically, resulting in stable, single-frequency operation. Blue light at 488 nm with an output power of 310 mW is generated with an optical-to-optical conversion efficiency of 18\%.},
  language  = {en}
}
@article{WangFruebingWirgesetal.2010,
  author    = {Wang, Feipeng and Fr{\"u}bing, Peter and Wirges, Werner and Gerhard, Reimund and Wegener, Michael},
  title     = {Enhanced Polarization in Melt-quenched and Stretched Poly(vinylidene Fluoride-Hexafluoropropylene) Films},
  issn      = {1070-9878},
  doi       = {10.1109/TDEI.2010.5539679},
  year      = {2010},
  abstract  = {beta-phase poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) copolymer films were prepared by uniaxially stretching solution-cast or melt-quenched samples. Different preparation routes lead to different amounts of the crystalline alpha and beta phases in the films, as detected by means of Fourier-transform infrared spectroscopy and X-ray diffractometry. The beta phase is significantly enhanced in melt-quenched and stretched films in comparison to solution-cast and stretched films. This is particularly true for copolymer samples with higher HFP content. The beta- phase enhancement is also observed in ferroelectric-hysteresis experiments where a rather high polarization of 58 mC/ m(2) was found on melt-quenched and stretched samples after poling at electric fields of 140 MV/m. After poling at 160 MV/m, one of these samples exhibited a piezoelectric d(33) coefficient as high as 21 pC/N. An electric-field-induced partial transition from the alpha to the beta phase was also observed on the melt-quenched and stretched samples. This effect leads to a further increase in the applications-relevant dipole polarization. Uniaxially stretched ferroelectric- polymer films are highly anisotropic. Dielectric resonance spectroscopy reveals a strong increase of the transverse piezoelectric d(32) coefficient and a strong decrease of the transverse elastic modulus c(32) upon heating from 20 to 50 degrees C.},
  language  = {en}
}
@article{WuZhouXiaoetal.2010,
  author    = {Wu, Ye Wu and Zhou, Changsong and Xiao, Jinghua and Kurths, J{\"u}rgen and Schellnhuber, Hans Joachim},
  title     = {Evidence for a bimodal distribution in human communication},
  issn      = {0027-8424},
  doi       = {10.1073/pnas.1013140107},
  year      = {2010},
  abstract  = {Interacting human activities underlie the patterns of many social, technological, and economic phenomena. Here we present clear empirical evidence from Short Message correspondence that observed human actions are the result of the interplay of three basic ingredients: Poisson initiation of tasks and decision making for task execution in individual humans as well as interaction among individuals. This interplay leads to new types of interevent time distribution, neither completely Poisson nor power-law, but a bimodal combination of them. We show that the events can be separated into independent bursts which are generated by frequent mutual interactions in short times following random initiations of communications in longer times by the individuals. We introduce a minimal model of two interacting priority queues incorporating the three basic ingredients which fits well the distributions using the parameters extracted from the empirical data. The model can also embrace a range of realistic social interacting systems such as e-mail and letter communications when taking the time scale of processing into account. Our findings provide insight into various human activities both at the individual and network level. Our analysis and modeling of bimodal activity in human communication from the viewpoint of the interplay between processes of different time scales is likely to shed light on bimodal phenomena in other complex systems, such as interevent times in earthquakes, rainfall, forest fire, and economic systems, etc.},
  language  = {en}
}
@article{ZunkovicProsen2010,
  author    = {Zunkovic, Bojan and Prosen, Tomaz},
  title     = {Explicit solution of the Lindblad equation for nearly isotropic boundary driven XY spin 1/2 chain},
  issn      = {1742-5468},
  doi       = {10.1088/1742-5468/2010/08/P08016},
  year      = {2010},
  abstract  = {Explicit solution for the two-point correlation function in a non-equilibrium steady state of a nearly isotropic boundary driven open XY spin 1/2 chain in the Lindblad formulation is provided. A non-equilibrium quantum phase transition from exponentially decaying correlations to long range order is discussed analytically. In the regime of long range order a new phenomenon of correlation resonances is reported, where the correlation response of the system is unusually high for certain discrete values of the external bulk parameter, e.g. the magnetic field.},
  language  = {en}
}
@article{WinterWinterFernandesGuimaraesetal.2010,
  author    = {Winter, Silvia Maria Giuliatti and Winter, Othon Cabo and Fernandes Guimar{\~a}es, Ana Helena and Silva, Maria Rita},
  title     = {Exploring S-type orbits in the Pluto-Charon binary system},
  issn      = {0035-8711},
  doi       = {10.1111/j.1365-2966.2010.16302.x},
  year      = {2010},
  abstract  = {This work generates, through a sample of numerical simulations of the restricted three-body problem, diagrams of semimajor axis and eccentricity which defines stable and unstable zones for particles in S-type orbits around Pluto and Charon. Since we consider initial conditions with 0 <= e <= 0.99, we found several new stable regions. We also identified the nature of each one of these newly found stable regions. They are all associated to families of periodic orbits derived from the planar circular restricted three-body problem. We have shown that a possible eccentricity of the Pluto-Charon system slightly reduces, but does not destroy, any of the stable regions.},
  language  = {en}
}