cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Metal-Quantum Dot-Topological Superconductor Junction: Kondo correlations and Majorana Bound States
Creators: name: Golub, Anatoly
name: Kuzmenko, Igor
name: Avishai, Yshai
Publisher: name: arXiv
Year: 2011
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Electron transport through [normal metal]-[quantum dot]-[topological superconductor] junction is studied and reveals interlacing physics of Kondo correlations with two Majorana fermions bound state residing on the opposite edges of the topological superconductor. When the strength of the Majorana fermion coupling exceeds the temperature $T$, this combination of Kono-Majorana fermion physics can be observed: The usual peak of the temperature dependent zero biased conductance $σ(V=0,T)$ splits and the conductance has a {\it dip} at T=0. The height of the conductance side-peaks decreases with magnetic field.
description: 5 two column pages
Can one identify the intrinsic structure of the yrast states in $^{48}$Cr after the backbending?
Creators: name: Gao, Zao-Chun
name: Horoi, Mihai
name: Chen, Y. S.
name: Chen, Y. J.
name: Tuya
Publisher: name: arXiv
Year: 2010
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The backbending phenomenon in $^{48}$Cr has been investigated using the recently developed Projected Configuration Interaction (PCI) method, in which the deformed intrinsic states are directly associated with shell model (SM) wavefunctions. Two previous explanations, (i) $K=0$ band crossing, and (ii) $K=2$ band crossing have been reinvestigated using PCI, and it was found that both explanations can successfully reproduce the experimental backbending. The PCI wavefunctions in the pictures of $K=0$ band crossing and $K=2$ band crossing are highly overlapped. We conclude that there are no unique intrinsic states associated with the yrast states after backbending in $^{48}$Cr.
description: 5 pages, 5 figures
Shock Wave Collisions and Thermalization in AdS_5
Creators: name: Kovchegov, Yuri V.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study heavy ion collisions at strong 't Hooft coupling using AdS/CFT correspondence. According to the AdS/CFT dictionary heavy ion collisions correspond to gravitational shock wave collisions in AdS_5. We construct the metric in the forward light cone after the collision perturbatively through expansion of Einstein equations in graviton exchanges. We obtain an analytic expression for the metric including all-order graviton exchanges with one shock wave, while keeping the exchanges with another shock wave at the lowest order. We read off the corresponding energy-momentum tensor of the produced medium. Unfortunately this energy-momentum tensor does not correspond to ideal hydrodynamics, indicating that higher order graviton exchanges are needed to construct the full solution of the problem. We also show that shock waves must completely stop almost immediately after the collision in AdS_5, which, on the field theory side, corresponds to complete nuclear stopping due to strong coupling effects, likely leading to Landau hydrodynamics. Finally, we perform trapped surface analysis of the shock wave collisions demonstrating that a bulk black hole, corresponding to ideal hydrodynamics on the boundary, has to be created in such collisions, thus constructing a proof of thermalization in heavy ion collisions at strong coupling.
description: 10 pages, 6 figures, based on talks given at the Symposium on High Energy Strong Interactions 2010 (HESI 2010), Yukawa Institute for Theoretical Physics, Kyoto, Japan, August 9-13, 2010, and at the 4th International Conference on Hard and Electromagnetic Probes of High Energy Nuclear Collisions (Hard Probes 2010), Eilat, Israel, October 10-15, 2010
Resource Letter PTG-1: Precision Tests of Gravity
Creators: name: Will, Clifford M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This resource letter provides an introduction to some of the main current topics in experimental tests of general relativity as well as to some of the historical literature. It is intended to serve as a guide to the field for upper-division undergraduate and graduate students, both theoretical and experimental, and for workers in other fields of physics who wish learn about experimental gravity. The topics covered include alternative theories of gravity, tests of the principle of equivalence, solar-system and binary-pulsar tests, searches for new physics in gravitational arenas, and tests of gravity in new regimes, involving astrophysics and gravitational radiation.
description: 9 pages; submitted to American Journal of Physics
Integrability breakdown in longitudinaly trapped, one-dimensional bosonic gases
Creators: name: Mazets, Igor E.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: A system of identical bosons with short-range (contact) interactions is studied. Their motion is confined to one dimension by a tight lateral trapping potential and, additionally, subject to a weak harmonic confinement in the longitudinal direction. Finite delay time associated with penetration of quantum particles through each other in the course of a pairwise one-dimensional collision in the presence of the longitudinal potential makes the system non-integrable and, hence, provides a mechanism for relaxation to thermal equilibrium. To analyse this effect quantitatively in the limit of a non-degenerate gas, we develop a system of kinetic equations and solve it for small-amplitude monopole oscillations of the gas. The obtained damping rate is long enough to be neglected in a realistic cold-atom experiment, and therefore longitudinal trapping does not hinder integrable dynamics of atomic gases in the 1D regime.
A Silicon-Based Monolithic Optical Frequency Comb Source
Creators: name: Foster, Mark A.
name: Levy, Jacob S.
name: Kuzucu, Onur
name: Saha, Kasturi
name: Lipson, Michal
name: Gaeta, Alexander L.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Recently developed techniques for generating precisely equidistant optical frequencies over broad wavelength ranges are revolutionizing precision physical measurement [1-3]. These frequency "combs" are produced primarily using relatively large, ultrafast laser systems. However, recent research has shown that broad-bandwidth combs can be produced using highly-nonlinear interactions in microresonator optical parametric oscillators [4-11]. Such devices not only offer the potential for developing extremely compact optical atomic clocks but are also promising for astronomical spectroscopy [12-14], ultrashort pulse shaping [15], and ultrahigh-speed communications systems. Here we demonstrate the generation of broad-bandwidth optical frequency combs from a CMOS-compatible integrated microresonator [16,17], which is a fully-monolithic and sealed chip-scale device making it insensitive to the surrounding environment. We characterize the comb quality using a novel self-referencing method and verify that the comb line frequencies are equidistant over a bandwidth that is nearly an order of magnitude larger than previous measurements. In addition, we investigate the ultrafast temporal properties of the comb and demonstrate its potential to serve as a chip-scale source of ultrafast (sub-ps) pulses.
Manipulating thermal conductivity through substrate coupling
Creators: name: Guo, Zhixin
name: Zhang, Dier
name: Gong, Xin-Gao
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We report a new approach to the thermal conductivity manipulation -- substrate coupling. Generally, the phonon scattering with substrates can decrease the thermal conductivity, as observed in recent experiments. However, we find that at certain regions, the coupling to substrates can increase the thermal conductivity due to a reduction of anharmonic phonon scattering induced by shift of the phonon band to the low wave vector. In this way, the thermal conductivity can be efficiently manipulated via coupling to different substrates, without changing or destroying the material structures. This idea is demonstrated by calculating the thermal conductivity of modified double-walled carbon nanotubes and also by the ice nanotubes coupled within carbon nanotubes.
description: 5 figures
Flexible Session Management in a Distributed Environment
Creators: name: Miller, Zach
name: Bradley, Dan
name: Tannenbaum, Todd
name: Sfiligoi, Igor
Publisher: name: arXiv
Year: 2010
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Many secure communication libraries used by distributed systems, such as SSL, TLS, and Kerberos, fail to make a clear distinction between the authentication, session, and communication layers. In this paper we introduce CEDAR, the secure communication library used by the Condor High Throughput Computing software, and present the advantages to a distributed computing system resulting from CEDAR's separation of these layers. Regardless of the authentication method used, CEDAR establishes a secure session key, which has the flexibility to be used for multiple capabilities. We demonstrate how a layered approach to security sessions can avoid round-trips and latency inherent in network authentication. The creation of a distinct session management layer allows for optimizations to improve scalability by way of delegating sessions to other components in the system. This session delegation creates a chain of trust that reduces the overhead of establishing secure connections and enables centralized enforcement of system-wide security policies. Additionally, secure channels based upon UDP datagrams are often overlooked by existing libraries; we show how CEDAR's structure accommodates this as well. As an example of the utility of this work, we show how the use of delegated security sessions and other techniques inherent in CEDAR's architecture enables US CMS to meet their scalability requirements in deploying Condor over large-scale, wide-area grid systems.
Growing Massive Black Holes in a Local Group Environment: the Central Supermassive, Slowly Sinking, and Ejected Populations
Creators: name: Micic, Miroslav
name: Holley-Bockelmann, Kelly
name: Sigurdsson, Steinn
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We explore the growth of < 10^7 Msun black holes that reside at the centers of spiral and field dwarf galaxies in a Local Group type of environment. We use merger trees from a cosmological N-body simulation known as Via Lactea II (VL-2) as a framework to test two merger-driven semi-analytic recipes for black hole growth that include dynamical friction, tidal stripping, and gravitational wave recoil in over 20,000 merger tree realizations. First, we apply a Fundamental Plane limited (FPL) model to the growth of Sgr A*, which drives the central black hole to a maximum mass limited by the Black Hole Fundamental Plane after every merger. Next, we present a new model that allows for low-level Prolonged Gas Accretion (PGA) during the merger. We find that both models can generate a Sgr A* mass black hole. We predict a population of massive black holes in local field dwarf galaxies - if the VL-2 simulation is representative of the growth of the Local Group, we predict up to 35 massive black holes (< 10^6 Msun) in Local Group field dwarfs. We also predict that hundreds of < 10^5 Msun black holes fail to merge, and instead populate the Milky Way halo, with the most massive of them at roughly the virial radius. In addition, we find that there may be hundreds of massive black holes ejected from their hosts into the nearby intergalactic medium due to gravitational wave recoil. We discuss how the black hole population in the Local Group field dwarfs may help to constrain the growth mechanism for Sgr A*.
description: 25 pages, 19 figures, accepted for publication in MNRAS
Outage rates and outage durations of opportunistic relaying systems
Creators: name: Hadzi-Velkov, Zoran
name: Zlatanov, Nikola
Publisher: name: arXiv
Year: 2010
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Opportunistic relaying is a simple yet efficient cooperation scheme that achieves full diversity and preserves the spectral efficiency among the spatially distributed stations. However, the stations' mobility causes temporal correlation of the system's capacity outage events, which gives rise to its important second-order outage statistical parameters, such as the average outage rate (AOR) and the average outage duration (AOD). This letter presents exact analytical expressions for the AOR and the AOD of an opportunistic relaying system, which employs a mobile source and a mobile destination (without a direct path), and an arbitrary number of (fixed-gain amplify-and-forward or decode-and-forward) mobile relays in Rayleigh fading environment.
A Search for Defect Related Ferromagnetism in SrTiO$_3$
Creators: name: Crandles, D. A.
name: DesRoches, B.
name: Razavi, F. S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Room temperature ferromagnetic hysteresis is observed in commercial SrTiO$_3$ substrates purchased from a variety of suppliers. It is shown that the ferromagnetic signal comes from the unpolished surfaces. Surface impurity phases cannot be detected using either x-ray diffraction or energy dispersive x-ray spectra on the unpolished surfaces. However, a possible correlation between surface disorder (xray diffraction peak linewidth) and ferromagnetism is observed. Ar ion bombardment (10keV-90 keV) can be used to produce surface layer disorder but is not found to induce ferromagnetism. Annealing of the substrates at temperatures ranging from 600 to 1100 $^\circ$C is found to alter the hysteresis curves differently depending on whether the annealing is performed in air or in vacuum. Identical annealing behaviour is observed if the substrates are artificially spiked with iron. This suggests that the ferromagnetic hysteresis of as purchased SrTiO$_3$ could be due to Fe contamination of the unpolished surfaces. In addition, it is shown that no ferromagnetism is observed in samples that contain $10^{19}-10^{21}$ cm$^{-3}$ of oxygen vacancies if all the faces are polished.
description: 20 pages, 7 figures, 3 tables, accepted in Journal of Applied Physics
Eigenvalue bounds for Schrödinger operators with a homogeneous magnetic field
Creators: name: Frank, Rupert L.
name: Olofsson, Rikard
Publisher: name: arXiv
Year: 2011
Subjects: subject: Spectral Theory (math.SP)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We prove Lieb-Thirring inequalities for Schrödinger operators with a homogeneous magnetic field in two and three space dimensions. The inequalities bound sums of eigenvalues by a semi-classical approximation which depends on the strength of the magnetic field, and hence quantifies the diamagnetic behavior of the system. For a harmonic oscillator in a homogenous magnetic field, we obtain the sharp constants in the inequalities.
description: 12 pages
Lifetime of a target in the presence of N independent walkers
Creators: name: Rojo, Félix
name: Pury, Pedro A.
name: Budde, Carlos E.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study the survival probability of an immobile target in presence of N independent diffusing walkers. We address the problem of the Mean Target Lifetime and its dependence on the number and initial distribution of the walkers when the trapping is perfect or imperfect. We consider the diffusion on lattices and in the continuous space and we address the bulk limit corresponding to a density of diffusing particles and only one isolated trap. Also, we use intermittent motion for optimization of search strategies.
description: 18 pages, 5 figures. Accepted for publication in Physica A.
Timing Measurements of the Relativistic Binary Pulsar PSR B1913+16
Creators: name: Weisberg, Joel M.
name: Nice, David J.
name: Taylor, Joseph H.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present results of more than three decades of timing measurements of the first known binary pulsar, PSR B1913+16. Like most other pulsars, its rotational behavior over such long time scales is significantly affected by small-scale irregularities not explicitly accounted for in a deterministic model. Nevertheless, the physically important astrometric, spin, and orbital parameters are well determined and well decoupled from the timing noise. We have determined a significant result for proper motion, $μ_α = -1.43\pm0.13$, $μ_δ=-0.70\pm0.13$ mas yr$^{-1}$. The pulsar exhibited a small timing glitch in May 2003, with ${Δf}/f=3.7\times10^{-11}$, and a smaller timing peculiarity in mid-1992. A relativistic solution for orbital parameters yields improved mass estimates for the pulsar and its companion, $m_1=1.4398\pm0.0002 \ M_{\sun}$ and $m_2=1.3886\pm0.0002 \ M_{\sun}$. The system's orbital period has been decreasing at a rate $0.997\pm0.002$ times that predicted as a result of gravitational radiation damping in general relativity. As we have shown before, this result provides conclusive evidence for the existence of gravitational radiation as predicted by Einstein's theory.
description: Published in APJ, 722, 1030 (2010)
An algorithm for correcting CoRoT raw light curves
Creators: name: Mislis, D.
name: Schmitt, J. H. M. M.
name: Carone, L.
name: Guenther, E. W.
name: Patzold, M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We introduce the CoRoT detrend algorithm (CDA) for detrending CoRoT stellar light curves. The algorithm CDA has the capability to remove random jumps and systematic trends encountered in typical CoRoT data in a fully automatic fashion. Since enormous jumps in flux can destroy the information content of a light curve, such an algorithm is essential. From a study of 1030 light curves in the CoRoT IRa01 field, we developed three simple assumptions which upon CDA is based. We describe the algorithm analytically and provide some examples of how it works. We demonstrate the functionality of the algorithm in the cases of CoRoT0102702789, CoRoT0102874481, CoRoT0102741994, and CoRoT0102729260. Using CDA in the specific case of CoRoT0102729260, we detect a candidate exoplanet around the host star of spectral type G5, which remains undetected in the raw light curve, and estimate the planetary parameters to be Rp=6.27Re and P=1.6986 days.
description: 8 pages, 13 figures
Demonstration of the temporal matter-wave Talbot effect for trapped matter waves
Creators: name: Mark, Manfred J.
name: Haller, Elmar
name: Danzl, Johann G.
name: Lauber, Katharina
name: Gustavsson, Mattias
name: Nägerl, Hanns-Christoph
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We demonstrate the temporal Talbot effect for trapped matter waves using ultracold atoms in an optical lattice. We investigate the phase evolution of an array of essentially non-interacting matter waves and observe matter-wave collapse and revival in the form of a Talbot interference pattern. By using long expansion times, we image momentum space with sub-recoil resolution, allowing us to observe fractional Talbot fringes up to 10th order.
description: 17 pages, 7 figures
An efficient approximation to the correlated Nakagami-m sums and its application in equal gain diversity receivers
Creators: name: Zlatanov, Nikola
name: Hadzi-Velkov, Zoran
name: Karagiannidis, George
Publisher: name: arXiv
Year: 2010
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: There are several cases in wireless communications theory where the statistics of the sum of independent or correlated Nakagami-m random variables (RVs) is necessary to be known. However, a closed-form solution to the distribution of this sum does not exist when the number of constituent RVs exceeds two, even for the special case of Rayleigh fading. In this paper, we present an efficient closed-form approximation for the distribution of the sum of arbitrary correlated Nakagami-m envelopes with identical and integer fading parameters. The distribution becomes exact for maximal correlation, while the tightness of the proposed approximation is validated statistically by using the Chi-square and the Kolmogorov-Smirnov goodness-of-fit tests. As an application, the approximation is used to study the performance of equal-gain combining (EGC) systems operating over arbitrary correlated Nakagami-m fading channels, by utilizing the available analytical results for the error-rate performance of an equivalent maximal-ratio combining (MRC) system.
High temperature thermodynamics of fermionic alkaline earth atoms in optical lattices
Creators: name: Hazzard, Kaden R. A.
name: Gurarie, Victor
name: Hermele, Michael
name: Rey, Ana Maria
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We calculate experimentally relevant properties of trapped fermionic alkaline earth atoms in an optical lattice, modeled by the SU(N) Hubbard model. Our calculation is accurate when the temperature is much larger than the tunneling rate, similar to current regimes in ultracold atom experiments. In addition to exploring the Mott insulator-metal crossover, we calculate final temperatures achieved by the standard experimental protocol of adiabatically ramping from a non-interacting gas, as a function of initial gas temperature and final state lattice parameters. Of particular experimental interest, we find that increasing $N$ gives substantially \textit{colder} Mott insulators, up to more than a factor of five for relevant parameters. This cooling happens for all $N$, fixing the initial entropy, or for all $N \lsim 20$ (the exact value depends on dimensionality), fixing the initial temperature.
description: 4+ pages main text, 2 figures. 3 pages supplementary information, 2 figures. v2: added citation
Quantifying the nonlocality of GHZ quantum correlations by a bounded communication simulation protocol
Creators: name: Branciard, Cyril
name: Gisin, Nicolas
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The simulation of quantum correlations with alternative nonlocal resources, such as classical communication, gives a natural way to quantify their nonlocality. While multipartite nonlocal correlations appear to be useful resources, very little is known on how to simulate multipartite quantum correlations. We present the first known protocol that reproduces 3-partite GHZ correlations with bounded communication: 3 bits in total turn out to be sufficient to simulate all equatorial Von Neumann measurements on the 3-partite GHZ state.
description: 7 pages, 1 figure
Yangian in the Twistor String
Creators: name: Corn, John
name: Creutzig, Thomas
name: Dolan, Louise
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study symmetries of the quantized open twistor string. In addition to global PSL(4|4) symmetry, we find non-local conserved currents. The associated non-local charges lead to Ward identities which show that these charges annihilate the string gluon tree amplitudes, and have the same form as symmetries of amplitudes in N=4 super conformal Yang Mills theory. We describe how states of the open twistor string form a realization of the PSL(4|4) Yangian superalgebra.
description: 37 pages, 4 figures
High Performance In Vivo Near-IR (>1 μm) Imaging and Photothermal Cancer Therapy with Carbon Nanotubes
Creators: name: Robinson, Joshua T.
name: Welsher, Kevin
name: Tabakman, Scott M.
name: Sherlock, Sarah P.
name: Wang, Hailiang
name: Luong, Richard
name: Dai, Hongjie
Publisher: name: arXiv
Year: 2010
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Short single-walled carbon nanotubes (SWNTs) functionalized by PEGylated phospholipids are biologically non-toxic and long-circulating nanomaterials with intrinsic near infrared photoluminescence (NIR PL), characteristic Raman spectra, and strong optical absorbance in the near infrared (NIR). This work demonstrates the first dual application of intravenously injected SWNTs as photoluminescent agents for in vivo tumor imaging in the 1.0-1.4 μm emission region and as NIR absorbers and heaters at 808 nm for photothermal tumor elimination at the lowest injected dose (70 μg of SWNT/mouse, equivalent to 3.6 mg/kg) and laser irradiation power (0.6 W/cm2) reported to date. Ex vivo resonance Raman imaging revealed the SWNT distribution within tumors at a high spatial resolution. Complete tumor elimination was achieved for large numbers of photothermally treated mice without any toxic side effects after more than six months post-treatment. Further, side-by-side experiments were carried out to compare the performance of SWNTs and gold nanorods (AuNRs) at an injected dose of 700 μg of AuNR/mouse (equivalent to 35 mg/kg) in NIR photothermal ablation of tumors in vivo. Highly effective tumor elimination with SWNTs was achieved at 10 times lower injected doses and lower irradiation powers than for AuNRs. These results suggest there are significant benefits of utilizing the intrinsic properties of biocompatible SWNTs for combined cancer imaging and therapy.
description: Nanoresearch, in press
Microstructure of epitaxial strained BiCrO3 thin films
Creators: name: David, Adrian
name: Boullay, Philippe
name: Mangalam, Vengadesh
name: Barrier, Nicolas
name: Prellier, Wilfrid
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The structure and microstrucutre of fully-strained BiCrO3 thin films have been investigated by X-rays diffraction and transmission electron microscopy, at room temperature. Interestingly, three structural variants are simultaneously stabilized within the film. While txo of them are consistent with the existing phases in the bulk-below and above the 420 K structural transition, a different phase is identified. The existence of various structures has been attributed to the inhomogeneous distribution of local strains and oxygens resulting from a minimization of the strain-energy at the interface. These findings will open the route to a better understanding of Bi-based perovskites and metastable phases.
description: 10 pages, 5 figures, to be published in Applied Physics Letters
Hall effect of FeTe and Fe(Se_1-x_Te_x_) thin films
Creators: name: Tsukada, I.
name: Hanawa, M.
name: komiya, Seiki
name: Ichinose, A.
name: Akiike, T.
name: Imai, Y.
name: Maeda, A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The Hall effect is investigated in thin-film samples of iron-chalcogenide superconductors in detail. The Hall coefficient (RH) of FeTe and Fe(Se1-xTex) exhibits a similar positive value around 300 K, indicating that the high-temperature normal state is dominated by hole-channel transport. FeTe exhibits a sign reversal from positive to negative across the transition to the low-temperature antiferromagnetic state, indicating the occurrence of drastic reconstruction in the band structure. The mobility analysis using the carrier density theoretically calculated reveals that the mobility of holes is strongly suppressed to zero, and hence the electric transport looks to be dominated by electrons. The Se substitution to Te suppresses the antiferromagnetic long-range order and induces superconductivity instead. The similar mobility analysis for Fe(Se0.4Te0.6) and Fe(Se0.5Te0.5) thin films shows that the mobility of electrons increases with decreasing temperature even in the paramagnetic state, and keeps sufficiently high values down to the superconducting transition temperature. From the comparison between FeTe and Fe(Se1-xTex), it is suggested that the coexistence of 'itinerant' carriers both in electron and hole channels is indispensable for the occurrence of superconductivity.
description: 16 page, 6 figures, Proceedings of ISS-2010, to be published in Physica C
Entropic Inference
Creators: name: Caticha, Ariel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Methodology (stat.ME)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: In this tutorial we review the essential arguments behing entropic inference. We focus on the epistemological notion of information and its relation to the Bayesian beliefs of rational agents. The problem of updating from a prior to a posterior probability distribution is tackled through an eliminative induction process that singles out the logarithmic relative entropy as the unique tool for inference. The resulting method of Maximum relative Entropy (ME), includes as special cases both MaxEnt and Bayes' rule, and therefore unifies the two themes of these workshops -- the Maximum Entropy and the Bayesian methods -- into a single general inference scheme.
description: Presented at MaxEnt 2010, the 30th International Workshop on Bayesian Inference and Maximum Entropy Methods in Science and Engineering (July 4-9, 2010, Chamonix, France)
Robustness of Fractional Quantum Hall States with Dipolar Atoms in Artificial Gauge Fields
Creators: name: Grass, T.
name: Baranov, M. A.
name: Lewenstein, M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: The robustness of fractional quantum Hall states is measured as the energy gap separating the Laughlin ground-state from excitations. Using thermodynamic approximations for the correlation functions of the Laughlin state and the quasihole state, we evaluate the gap in a two-dimensional system of dipolar atoms exposed to an artificial gauge field. For Abelian fields, our results agree well with the results of exact diagonalization for small systems, but indicate that the large value of the gap predicted in [Phys. Rev. Lett. 94, 070404 (2005)] was overestimated. However, we are able to show that the small gap found in the Abelian scenario is dramatically increased if we turn to non-Abelian fields squeezing the Landau levels.
Hidden-Markov Program Algebra with iteration
Creators: name: McIver, Annabelle
name: Meinicke, Larissa
name: Morgan, Carroll
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: We use Hidden Markov Models to motivate a quantitative compositional semantics for noninterference-based security with iteration, including a refinement- or "implements" relation that compares two programs with respect to their information leakage; and we propose a program algebra for source-level reasoning about such programs, in particular as a means of establishing that an "implementation" program leaks no more than its "specification" program. This joins two themes: we extend our earlier work, having iteration but only qualitative, by making it quantitative; and we extend our earlier quantitative work by including iteration. We advocate stepwise refinement and source-level program algebra, both as conceptual reasoning tools and as targets for automated assistance. A selection of algebraic laws is given to support this view in the case of quantitative noninterference; and it is demonstrated on a simple iterated password-guessing attack.
Dependence of elliptic flow on transverse momentum in 200 GeV Au-Au and 2.76 TeV Pb-Pb collisions
Creators: name: Li, Bao-Chun
name: Fu, Yuan-Yuan
name: Wang, Er-Qin
name: Liu, Fu-Hu
Publisher: name: arXiv
Year: 2011
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the dependence of elliptic flows $v_2$ on transverse momentum $P_T$ for charged hadrons produced in nucleus-nucleus collisions at high energy by using a multi-source ideal gas model which includes the interaction contribution of the emission sources. Our calculated results are approximately in agreement with the experimental data over a wider $P_T$ range from the STAR and ALICE Collaborations. It is found that the expansion factor increases linearly with the impact parameter from most central (0-5%) to mid-peripheral (35-40%) collisions.
description: 8 pages, 4 figures
The star formation history of the Large Magellanic Cloud as seen by star clusters and stars
Creators: name: Maschberger, Thomas
name: Kroupa, Pavel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The aim of this work is to test to what extent the star cluster population of a galaxy can be utilised to constrain or estimate the star formation history, with the Large Magellanic Cloud as our testbed. We follow two methods to extract information about the star formation rate from star clusters, either using only the most massive clusters (Maschberger & Kroupa 2007) or using the whole cluster population, albeit this is only possible for a shorter age span. We compare these results with the star formation history derived from colour-magnitude diagrams and find good overall agreement for the most recent approximately 1 Gyr. For later ages, and especially during the "cluster age gap", there is a deficiency of star clusters in relation to the star formation rate derived from the colour-magnitude diagram. The star formation rates following from the whole cluster population lie a factor of approximately 10 lower than the star formation rates deduced from the most massive clusters or from the colour-magnitude diagram, suggesting that only approximately 10 per cent of all stars form in long-lived bound star clusters.
description: MNRAS, in press, 9 pages, 8 figures
Unified Curvature Dynamics from Atomic to Galactic Scales: A Comprehensive Framework Based on the Ω-Model
Creators: name: Brent Jarvis
Publisher: name: Zenodo
Year: 2025
Subjects: subject: Physics
subject: Physics
subject: Physics/methods
subject: Nuclear physics
subject: Particle physics
subject: Atomic physics
subject: Nuclear physics
subject: Quantum physics
subject: Plasma physics
subject: Theoretical physics

description: This thesis presents the Ω-Model, a unified geometric framework integrating gravitational, electromagnetic, and inertial phenomena using dual-frequency spacetime curvature and toroidal geometry. We derive the generalized Ω-invariant and demonstrate predictions for planetary precession, lunar nutation, flat galactic rotation curves, relativistic binaries, and a dimensional constant linking curvature-induced acceleration to Newtonian gravity, entirely from first principles.
Analytical study of an exclusive genetic switch
Creators: name: Venegas-Ortiz, J.
name: Evans, M. R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Molecular Networks (q-bio.MN)
subject: FOS: Physical sciences
subject: FOS: Biological sciences
subject: 82

description: The nonequilibrium stationary state of an exclusive genetic switch is considered. The model comprises two competing species and a single binding site which, when bound to by a protein of one species, causes the other species to be repressed. The model may be thought of as a minimal model of the power struggle between two competing parties. Exact solutions are given for the limits of vanishing binding/unbinding rates and infinite binding/unbinding rates. A mean field theory is introduced which is exact in the limit of vanishing binding/unbinding rates. The mean field theory and numerical simulations reveal that generically bistability occurs and the system is in a symmetry broken state. An exact perturbative solution which in principle allows the nonequilibrium stationary state to be computed is also developed and computed to first and second order.
description: 28 pages, 6 figures
Herschel-ATLAS: Statistical Properties of Galactic Cirrus in the GAMA-9 Hour Science Demonstration Phase Field
Creators: name: Bracco, Andrea
name: Cooray, Asantha
name: Veneziani, M.
name: Amblard, A.
name: Serra, P.
name: Wardlow, J.
name: Thompson, M. ~A.
name: White, G.
name: Auld, R.
name: Baes, M.
name: Bertoldi, F.
name: Buttiglione, S.
name: Cava, A.
name: Clements, D. ~L.
name: Dariush, A.
name: De Zotti, G.
name: Dunne, L.
name: Dye, S.
name: Eales, S.
name: Fritz, J.
name: Gomez, H.
name: Hopwood, R.
name: Ibar, I.
name: Ivison, R. ~J.
name: Jarvis, M.
name: Lagache, G.
name: Lee, M. ~G.
name: Leeuw, L.
name: Maddox, S.
name: Michalowski, M.
name: Pearson, C.
name: Pohlen, M.
name: Rigby, E.
name: Rodighiero, G.
name: Smith, D. J. B.
name: Temi, P.
name: Vaccari, M.
name: van der Werf, P.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We study the Spectral Energy Distribution (SED) and the power spectrum of Galactic cirrus emission observed in the 14 deg^2 Science Demonstration Phase field of the Herschel-ATLAS using Herschel and IRAS data from 100 to 500 um. We compare the SPIRE 250, 350 and 500um maps with IRAS 100um emission, binned in 6' pixels. We assume a modified black-body SED with dust emissivity parameter beta (F ~ lambda^(-beta)) and a single dust temperature T_d, and find that the dust temperature and emissivity index varies over the science demonstration field as 10< T_rm < 25 K and 1 < beta< 4. The latter values are somewhat higher than the range of beta often quoted in the literature (1< beta< 2). We estimate the mean values of these parameters to be T_d=19.0 +/- 2.4 K and beta = 1.4 +/- 0.4. In regions of bright cirrus emission, we find that the dust has similar temperatures with T_d = 18.0 +/- 2.5 K, and similar values of beta, ranging from 1.4 +- 0.5 to 1.9+/- 0.5. We show that T_d and beta associated with diffuse cirrus emission are anti-correlated and can be described by the relationship: beta(T_d) = NT_d^alpha with [N=116+/-38, alpha=-1.4+/1 0.1]. The strong correlation found in this analysis is not just limited to high density clumps of cirrus emission as seen in previous studies, but is also seen in diffuse cirrus in low density regions. To provide an independent measure of $T_{\rm d}$ and $β$, we obtain the angular power spectrum of the cirrus emission in the {\it IRAS} and SPIRE maps, which is consistent with a power spectrum of the form P(k)=P_0(k/k_0)^gamma where gamma = â H R2.6+/-m 0.2 for scales of 50-200' in the SPIRE maps. The cirrus rms fluctuation amplitude at angular scales of 100' is consistent with a modified blackbody SED with T_d = 20.1+/- 0.9 K and beta = 1.3+/- 0.2, in agreement with the values obtained above.
description: 11 Pages; accepted for publication in MNRAS Herschel Special Issue
Chronic Activation of AMPK Induces Mitochondrial Biogenesis through Differential Phosphorylation and Abundance of Mitochondrial Proteins in Dictyostelium discoideum
Creators: name: Heidorn-Czarna, Malgorzata
name: Heidorn, Herbert-Michael
name: Fernando, Sanjanie
name: Sanislav, Oana
name: Jarmuszkiewicz, Wieslawa
name: Mutzel, Rupert
name: Fisher, Paul R.
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: AMP-activated protein kinase
subject: AMPK
subject: mTORC1
subject: mitochondrial biogenesis
subject: mitochondrial phosphoproteome
subject: phosphoproteomics
subject: Dictyostelium discoideum
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: Mitochondrial biogenesis is a highly controlled process that depends on diverse signalling pathways responding to cellular and environmental signals. AMP-activated protein kinase (AMPK) is a critical metabolic enzyme that acts at a central control point in cellular energy homeostasis. Numerous studies have revealed the crucial roles of AMPK in the regulation of mitochondrial biogenesis; however, molecular mechanisms underlying this process are still largely unknown. Previously, we have shown that, in cellular slime mould Dictyostelium discoideum, the overexpression of the catalytic α subunit of AMPK led to enhanced mitochondrial biogenesis, which was accompanied by reduced cell growth and aberrant development. Here, we applied mass spectrometry-based proteomics of Dictyostelium mitochondria to determine the impact of chronically active AMPKα on the phosphorylation state and abundance of mitochondrial proteins and to identify potential protein targets leading to the biogenesis of mitochondria. Our results demonstrate that enhanced mitochondrial biogenesis is associated with variations in the phosphorylation levels and abundance of proteins related to energy metabolism, protein synthesis, transport, inner membrane biogenesis, and cellular signalling. The observed changes are accompanied by elevated mitochondrial respiratory activity in the AMPK overexpression strain. Our work is the first study reporting on the global phosphoproteome profiling of D. discoideum mitochondria and its changes as a response to constitutively active AMPK. We also propose an interplay between the AMPK and mTORC1 signalling pathways in controlling the cellular growth and biogenesis of mitochondria in Dictyostelium as a model organism.
Evaluating skyscraper design and construction technologies on an international basis
Creators: name: Abo Moslim, Saad Allah Fathy
Publisher: name: University of British Columbia
Year: 2017

description: Design and construction functions of skyscrapers tend to draw from the best practices and technologies available worldwide in order to meet their development, design, construction, and performance challenges. Given the availability of many alternative solutions for different facets of a building’s design and construction systems, the need exists for an evaluation framework that is comprehensive in scope, transparent as to the basis for decisions made, reliable in result, and practical in application. Findings from the literature reviewed combined with a deep understanding of the evaluation process of skyscraper systems were used to identify the components and their properties of such a framework, with emphasis on selection of categories, perspectives, criteria, and sub-criteria, completeness of these categories and perspectives, and clarity in the language, expression and level of detail used. The developed framework divided the evaluation process for candidate solutions into the application of three integrated filters. The first filter screens alternative solutions using two-comprehensive checklists of stakeholder acceptance and local feasibility criteria/sub-criteria on a pass-fail basis to eliminate the solutions that do not fit with local cultural norms, delivery capabilities, etc. The second filter treats criteria related to design, quality, production, logistics, installation, and in-use perspectives for assessing the technical performance of the first filter survivors in order to rank them. The third filter evaluates the financial performance expressed in terms of Net Present Value of a skyscraper project over its life cycle as a function of system solutions being considered, and involves treatment of all major cash flow streams (revenues and expenditures), and their timing. Product and process models are developed to provide the cash flow model with the required scope and time information. The most preferred solution is recommended on the basis of filter two and three results. Efficacy of the developed framework and each filter were assessed through their application to many case studies and through interviews with construction professionals. Findings show that the framework addresses the deficiencies identified in the existing literature and can improve the quality of the decision-making process when selecting preferred solutions for building a specific skyscraper in a specific geographic area.
Calving Management: A Questionnaire Survey of Veterinary Subject Matter Experts and Non-Experts
Creators: name: Voß, Anna Lisa
name: Heuwieser, Wolfgang
name: Mee, John F.
name: Fischer-Tenhagen, Carola
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: survey
subject: veterinarians
subject: dairy
subject: calving management
subject: calving prediction
subject: signs of imminent parturition
subject: maternity pen
subject: 600 Technik, Medizin, angewandte Wissenschaften::630 Landwirtschaft::630 Landwirtschaft und verwandte Bereiche
subject: 600 Technik, Medizin, angewandte Wissenschaften::630 Landwirtschaft::636 Viehwirtschaft

description: Accurate detection of the onset of parturition is a key factor in the prevention of dystocia. In order to establish current best practice recommendations for calving management, we asked subject matter experts (SME) who had published on calving management (by online survey, n = 80) and non-SMEs, veterinary practitioners (by workshop survey, n = 24) for their opinions. For this, we designed a questionnaire on the significance of signs of imminent parturition (SIP), the frequency of calving observation, and influencing factors for the timing of cow movement to a maternity pen. The response rate was 67.5% in the online survey and 100% in the workshop survey. The majority (89.7%) of all respondents agreed that it is beneficial for successful calving management to differentiate between stage I and II of parturition. Of 12 signs of imminent parturition (for stage I and II), “restlessness” and “visibility of fetal parts in vulva” were cited by 56.5% and 73.3% of SME and non-SME respondents, respectively. There was no consensus on the right time to move the cow to the maternity pen; recommendations varied from one to over 21 days. Almost half of the respondents (45.7%) recommended a 6-h observation interval for prepartum cows in the maternity pen. This study identified a strong consensus on the SIP and how and when to observe cows prior to parturition. SMEs and non-SMEs provided broadly similar recommendations, while the SMEs and the non-SMEs differed significantly in the number of publications on calving they authored, they differed little in their knowledge of calving management.