837 research outputs found

    Angle Dependent Magnetoresistance of the Layered Organic Superconductor \kappa-(ET)2Cu(NCS)2: Simulation and Experiment

    Full text link
    The angle-dependences of the magnetoresistance of two different isotopic substitutions (deuterated and undeuterated) of the layered organic superconductor \kappa-(ET)2Cu(NCS)2 are presented. The angle dependent magnetoresistance oscillations (AMRO) arising from the quasi-one-dimensional (Q1D) and quasi-two-dimensional (Q2D) Fermi surfaces in this material are often confused. By using the Boltzman transport equation extensive simulations of the AMRO are made that reveal the subtle differences between the different species of oscillation. No significant differences are observed in the electronic parameters derived from quantum oscillations and AMRO for the two isotopic substitutions. The interlayer transfer integrals are determined for both isotopic substitutions and a slight difference is observed which may account for the negative isotope effect previously reported [1]. The success of the semi-classical simulations suggests that non-Fermi liquid effects are not required to explain the interlayer-transport in this system.Comment: 15 pages, 16 figure

    Theory of the optical properties of non-absorbing compensated cholesteric liquid crystals

    Get PDF
    A theory is developed of the optical properties of a non-absorbing compensated cholesteric liquid crystal. It is shown that the Mauguin-de Vries equation fails when the pitch becomes very large. Theoretical curves are presented of the dependence of the rotatory power on pitch for different values of the sample thickness. The results are in agreement with the observed variation of the rotatory power of a compensated cholesteric mixture with temperature

    From LTL and Limit-Deterministic B\"uchi Automata to Deterministic Parity Automata

    Full text link
    Controller synthesis for general linear temporal logic (LTL) objectives is a challenging task. The standard approach involves translating the LTL objective into a deterministic parity automaton (DPA) by means of the Safra-Piterman construction. One of the challenges is the size of the DPA, which often grows very fast in practice, and can reach double exponential size in the length of the LTL formula. In this paper we describe a single exponential translation from limit-deterministic B\"uchi automata (LDBA) to DPA, and show that it can be concatenated with a recent efficient translation from LTL to LDBA to yield a double exponential, \enquote{Safraless} LTL-to-DPA construction. We also report on an implementation, a comparison with the SPOT library, and performance on several sets of formulas, including instances from the 2016 SyntComp competition

    Cytoplasmic Poly(A) Binding Protein-1 Binds to Genomically Encoded Sequences Within Mammalian mRNAs

    Get PDF
    The functions of the major mammalian cytoplasmic poly(A) binding protein, PABPC1, have been characterized predominantly in the context of its binding to the 3′ poly(A) tails of mRNAs. These interactions play important roles in post-transcriptional gene regulation by enhancing translation and mRNA stability. Here, we performed transcriptome-wide CLIP-seq analysis to identify additional PABPC1 binding sites within genomically encoded mRNA sequences that may impact on gene regulation. From this analysis, we found that PABPC1 binds directly to the canonical polyadenylation signal in thousands of mRNAs in the mouse transcriptome. PABPC1 binding also maps to translation initiation and termination sites bracketing open reading frames, exemplified most dramatically in replication-dependent histone mRNAs. Additionally, a more restricted subset of PABPC1 interaction sites comprised A-rich sequences within the 5′ UTRs of mRNAs, including Pabpc1 mRNA itself. Functional analyses revealed that these PABPC1 interactions in the 5′ UTR mediate both auto- and trans-regulatory translational control. In total, these findings reveal a repertoire of PABPC1 binding that is substantially broader than previously recognized with a corresponding potential to impact and coordinate post-transcriptional controls critical to a broad array of cellular functions

    Test for interlayer coherence in a quasi-two-dimensional superconductor

    Full text link
    Peaks in the magnetoresistivity of the layered superconductor κ\kappa-(BEDT-TTF)2_2Cu(NCS)2_2, measured in fields 45\leq 45 T applied within the layers, show that the Fermi surface is extended in the interlayer direction and enable the interlayer transfer integral (t0.04t_{\perp} \approx 0.04 meV) to be deduced. However, the quasiparticle scattering rate τ1\tau^{-1} is such that /τ6t\hbar/\tau \sim 6t_{\perp}, implying that κ\kappa-(BEDT-TTF)2_2Cu(NCS)2_2 meets the criterion used to identify interlayer incoherence. The applicability of this criterion to anisotropic materials is thus shown to be questionable.Comment: 5 pages, 4 figure

    Efficient Online Timed Pattern Matching by Automata-Based Skipping

    Full text link
    The timed pattern matching problem is an actively studied topic because of its relevance in monitoring of real-time systems. There one is given a log ww and a specification A\mathcal{A} (given by a timed word and a timed automaton in this paper), and one wishes to return the set of intervals for which the log ww, when restricted to the interval, satisfies the specification A\mathcal{A}. In our previous work we presented an efficient timed pattern matching algorithm: it adopts a skipping mechanism inspired by the classic Boyer--Moore (BM) string matching algorithm. In this work we tackle the problem of online timed pattern matching, towards embedded applications where it is vital to process a vast amount of incoming data in a timely manner. Specifically, we start with the Franek-Jennings-Smyth (FJS) string matching algorithm---a recent variant of the BM algorithm---and extend it to timed pattern matching. Our experiments indicate the efficiency of our FJS-type algorithm in online and offline timed pattern matching

    Substitution Effect by Deuterated Donors on Superconductivity in κ\kappa-(BEDT-TTF)2_2Cu[N(CN)2_2]Br

    Full text link
    We investigate the superconductivity in the deuterated BEDT-TTF molecular substitution system κ\kappa-[(h8-BEDT-TTF)1x_{1-x}(d8-BEDT-TTF)x_x]2_2Cu[N(CN)2_2]Br, where h8 and d8 denote fully hydrogenated and deuterated molecules, respectively. Systematic and wide range (xx = 0 -- 1) substitution can control chemical pressure finely near the Mott boundary, which results in the modification of the superconductivity. After cooling slowly, the increase of TcT_{\textrm{c}} observed up to xx \sim 0.1 is evidently caused by the chemical pressure effect. Neither reduction of TcT_{\textrm{c}} nor suppression of superconducting volume fraction is found below xx \sim 0.5. This demonstrates that the effect of disorder by substitution is negligible in the present system. With further increase of xx, both TcT_{\textrm{c}} and superconducting volume fraction start to decrease toward the values in xx = 1.Comment: J. Phys. Soc. Jp

    Bhjet: a public multi-zone, steady state jet + thermal corona spectral model

    Get PDF
    Accreting black holes are sources of major interest in astronomy, particular those launching jets because of their ability to accelerate particles, and dramatically affect their surrounding environment up to very large distances. The spatial, energy and time scales at which a central active black hole radiates and impacts its environment depend on its mass. The implied scale-invariance of accretion/ejection physics between black hole systems of different central masses has been confirmed by several studies. Therefore, designing a self-consistent theoretical model that can describe such systems, regardless of their mass, is of crucial importance to tackle a variety of astrophysical sources. We present here a new and significantly improved version of a scale invariant, steady-state, multi-zone jet model, which we rename bhjet, resulting from the efforts of our group to advance the modelling of black hole systems. We summarise the model assumptions and basic equations, how they have evolved over time, and the additional features that we have recently introduced. These include additional input electron populations, the extension to cyclotron emission in near-relativistic regime, an improved multiple inverse Compton scattering method, external photon seeds typical of AGN and a magnetically-dominated jet dynamical model as opposed to the pressure-driven jet configuration present in older versions. In this paper, we publicly release the code on Github and, in order to facilitate the user's approach to its many possibilities, showcase a few applications as a tutorial.Comment: 28 pages, 16 figures, accepted for publication on MNRAS, code available at https://github.com/matteolucchini1/BHJet/, updated to the latest version of the manuscrip
    corecore