A Study of Finite Temperature Gauge Theory in (2+1) Dimensions

We determine the critical couplings and the critical exponents of the finite temperature transition in SU(2) and SU(3) pure gauge theory in (2+1) dimensions. We also measure Wilson loops at $T=0$ on a wide range of $\beta$ values using APE smearing to improve the signal. We extract the string tension $\sigma$ from a fit to large distances, including a string fluctuation term. With these two entities we calculate $T_c/\sqrt{\sigma}$.Comment: Talk presented at LATTICE96(finite temperature), not espcrc2 style: 7 pages, 4 ps figures, 22 k

Variety of idempotents in nonassociative algebras

In this paper, we study the variety of all nonassociative (NA) algebras from the idempotent point of view. We are interested, in particular, in the spectral properties of idempotents when algebra is generic, i.e. idempotents are in general position. Our main result states that in this case, there exist at least $n-1$ nontrivial obstructions (syzygies) on the Peirce spectrum of a generic NA algebra of dimension $n$. We also discuss the exceptionality of the eigenvalue $\lambda=\frac12$ which appears in the spectrum of idempotents in many classical examples of NA algebras and characterize its extremal properties in metrised algebras.Comment: 27 pages, 1 figure, submitte

A Semiconductor Nanowire-Based Superconducting Qubit

We introduce a hybrid qubit based on a semiconductor nanowire with an epitaxially grown superconductor layer. Josephson energy of the transmon-like device ("gatemon") is controlled by an electrostatic gate that depletes carriers in a semiconducting weak link region. Strong coupling to an on-chip microwave cavity and coherent qubit control via gate voltage pulses is demonstrated, yielding reasonably long relaxation times (0.8 {\mu}s) and dephasing times (1 {\mu}s), exceeding gate operation times by two orders of magnitude, in these first-generation devices. Because qubit control relies on voltages rather than fluxes, dissipation in resistive control lines is reduced, screening reduces crosstalk, and the absence of flux control allows operation in a magnetic field, relevant for topological quantum information

QCD Thermodynamics with Improved Actions

The thermodynamics of the SU(3) gauge theory has been analyzed with tree level and tadpole improved Symanzik actions. A comparison with the continuum extrapolated results for the standard Wilson action shows that improved actions lead to a drastic reduction of finite cut-off effects already on lattices with temporal extent $N_\tau=4$. Results for the pressure, the critical temperature, surface tension and latent heat are presented. First results for the thermodynamics of four-flavour QCD with an improved staggered action are also presented. They indicate similarly large improvement factors for bulk thermodynamics.Comment: Talk presented at LATTICE96(finite temperature) 4 pages, LaTeX2e file, 6 eps-file

Validation of the Rheumatoid and Arthritis Outcome Score (RAOS) for the lower extremity

BACKGROUND: Patients with inflammatory joint diseases tend due to new treatments to be more physically active; something not taken into account by currently used outcome measures. The Rheumatoid and Arthritis Outcome Score (RAOS) is an adaptation of the Knee injury and Osteoarthritis Outcome Score (KOOS) and evaluates functional limitations of importance to physically active people with inflammatory joint diseases and problems from the lower extremities. The aim of the study was to test the RAOS for validity, reliability and responsiveness. METHODS: 119 in-patients with inflammatory joint disease (51% RA) admitted to multidisciplinary care, mean age 56 (±13), 73% women, mean disease duration 18 (±14) yr were consecutively enrolled. They all received the RAOS, the SF-36, the HAQ and four subscales of the AIMS2 twice during their stay for test of validity and responsiveness. Test-retest reliability of the RAOS questionnaire was calculated on 52 patients using the first or second administration and an additional mailed questionnaire. RESULTS: The RAOS met set criteria of reliability and validity. The random intraclass correlation coefficient (ICC (2,1)) for the five subscales ranged from 0.76 to 0.92, indicating that individual comparisons were possible except for the subscale Sport and Recreation Function. Inter-item correlation measured by Cronbach's alpha ranged from 0.78 to 0.95. When measuring construct validity the highest correlations occurred between subscales intended to measure similar constructs. Change over time (24 (± 7) days) due to multidisciplinary care was significant for all subscales (p < 0.001). The effect sizes ranged from 0.30–0.44 and were considered small to medium. All the RAOS subscales were more responsive than the HAQ. Some of the SF-36 subscales and the AIMS2 subscales were more responsive than the RAOS subscales. CONCLUSION: It is possible to adapt already existing outcome measures to assess other groups with musculoskeletal difficulties in the lower extremity. The RAOS is a reliable, valid and responsive outcome instrument for assessment of multidisciplinary care. To fully validate the RAOS further studies are needed in other populations

Etanercept, infliximab, and leflunomide in established rheumatoid arthritis: clinical experience using a structured follow up programme in southern Sweden.

OBJECTIVE: To explore the feasibility of prospectively monitoring treatment efficacy and tolerability of infliximab, etanercept, and leflunomide over a two year period in patients with established rheumatoid arthritis (RA) in clinical practice using a structured protocol. METHODS: All patients with RA at seven centres in southern Sweden, for whom at least two disease modifying antirheumatic drugs, including methotrexate, had failed or not been tolerated, who started treatment with either infliximab, etanercept, or leflunomide were included. They were evaluated at predefined times using a standardised protocol including items required for evaluating response to the American College of Rheumatology (ACR) or EULAR criteria. All adverse events were recorded using World Health Organisation terminology. Concomitant treatment and survival while receiving a drug were recorded. RESULTS: During the study 166 patients were treated with etanercept, 135 with infliximab, and 103 with leflunomide. Treatment response as determined by the ACR and EULAR response criteria was similar for the tumour necrosis factor (TNF) blockers. The TNF blockers performed significantly better than leflunomide both as determined by the response criteria and by survival on drug analysis. Thus 79% and 75% continued to receive etanercept or infliximab compared with 22% of patients who started leflunomide after 20 months. The spectrum of side effects did not differ from those previously reported in the clinical trials. The initial two year experience of a protocol for postmarketing surveillance of etanercept, infliximab, and leflunomide shows that a structured protocol with central data handling can be used in clinical practice for documenting the performance of newly introduced drugs. CONCLUSIONS: Efficacy data for the TNF blockers comply with results in clinical trials, whereas leflunomide appeared to perform worse than in clinical trials. Prolonged monitoring is required to identify possible rare side effects

Voltage-Controlled Superconducting Quantum Bus

We demonstrate the ability of an epitaxial semiconductor-superconductor nanowire to serve as a field-effect switch to tune a superconducting cavity. Two superconducting gatemon qubits are coupled to the cavity, which acts as a quantum bus. Using a gate voltage to control the superconducting switch yields up to a factor of 8 change in qubit-qubit coupling between the on and off states without detrimental effect on qubit coherence. High-bandwidth operation of the coupling switch on nanosecond timescales degrades qubit coherence

Anharmonicity of a Gatemon Qubit with a Few-Mode Josephson Junction

Coherent operation of gate-voltage-controlled hybrid transmon qubits (gatemons) based on semiconductor nanowires was recently demonstrated. Here we experimentally investigate the anharmonicity in epitaxial InAs-Al Josephson junctions, a key parameter for their use as a qubit. Anharmonicity is found to be reduced by roughly a factor of two compared to conventional metallic junctions, and dependent on gate voltage. Experimental results are consistent with a theoretical model, indicating that Josephson coupling is mediated by a small number of highly transmitting modes in the semiconductor junction

The converse problem for the multipotentialisation of evolution equations and systems

We propose a method to identify and classify evolution equations and systems that can be multipotentialised in given target equations or target systems. We refer to this as the {\it converse problem}. Although we mainly study a method for $(1+1)$-dimensional equations/system, we do also propose an extension of the methodology to higher-dimensional evolution equations. An important point is that the proposed converse method allows one to identify certain types of auto-B\"acklund transformations for the equations/systems. In this respect we define the {\it triangular-auto-B\"acklund transformation} and derive its connections to the converse problem. Several explicit examples are given. In particular we investigate a class of linearisable third-order evolution equations, a fifth-order symmetry-integrable evolution equation as well as linearisable systems.Comment: 31 Pages, 7 diagrams, submitted for consideratio

Tracer concentration profiles measured in central London as part of the REPARTEE campaign

There have been relatively few tracer experiments carried out that have looked at vertical plume spread in urban areas. In this paper we present results from two tracer (cyclic perfluorocarbon) experiments carried out in 2006 and 2007 in central London centred on the BT Tower as part of the REPARTEE (Regent’s Park and Tower Environmental Experiment) campaign. The height of the tower gives a unique opportunity to study vertical dispersion profiles and transport times in central London. Vertical gradients are contrasted with the relevant Pasquill stability classes. Estimation of lateral advection and vertical mixing times are made and compared with previous measurements. Data are then compared with a simple operational dispersion model and contrasted with data taken in central London as part of the DAPPLE campaign. This correlates dosage with non-dimensionalised distance from source. Such analyses illustrate the feasibility of the use of these empirical correlations over these prescribed distances in central London