111 research outputs found

    Search for the standard model Higgs boson at LEP

    Get PDF

    Searches for neutral Higgs bosons in e+e−e^{+}e^{-} collisions at centre-of-mass energies from 192 to 202 GeV

    Get PDF
    Searches for neutral Higgs bosons are performed with the 237 pb^-1 of data collected in 1999 by the ALEPH detector at LEP, for centre-of-mass energies between 191.6 and 201.6 GeV. These searches apply to Higgs bosons within the context of the Standard Model and its minimal supersymmetric extension (MSSM) as well as to invisibly decaying Higgs bosons. No evidence of a signal is seen. A lower limit on the mass of the Standard Model Higgs boson of 107.7 GeV/c^2 at 95% confidence level is set. In the MSSM, lower limits of 91.2 and 91.6 GeV/c^2 are derived for the masses of the neutral Higgs bosons h and A, respectively. For a Higgs boson decaying invisibly and produced with the Standard Model cross section, masses below 106.4 GeV/c^2 are excluded

    Measurement of W-pair production in e+e−e^+ e^- collisions at 189 GeV

    Get PDF
    The production of W-pairs is analysed in a data samplecollected by ALEPH at a mean centre-of-mass energy of 188.6 GeV,corresponding to an integrated luminosity of 174.2 pb^-1. Crosssections are given for different topologies of W decays intoleptons or hadrons. Combining all final states and assumingStandard Model branching fractions, the total W-pair cross sectionis measured to be 15.71 +- 0.34 (stat) +- 0.18 (syst) pb.Using also the W-pair data samples collected by ALEPH at lowercentre-of-mass energies, the decay branching fraction of the W bosoninto hadrons is measured to be BR (W hadrons) = 66.97+- 0.65 (stat) +- 0.32 (syst) %, allowing a determination of theCKM matrix element |V(cs)|= 0.951 +- 0.030 (stat) +- 0.015 (syst)

    Movement distributions of stroke survivors exhibit distinct patterns that evolve with training

    Full text link
    BACKGROUND: While clinical assessments provide tools for characterizing abilities in motor-impaired individuals, concerns remain over their repeatability and reliability. Typical robot-assisted training studies focus on repetition of prescribed actions, yet such movement data provides an incomplete account of abnormal patterns of coordination. Recent studies have shown positive effects from self-directed movement, yet such a training paradigm leads to challenges in how to quantify and interpret performance. METHODS: With data from chronic stroke survivors (n = 10, practicing for 3 days), we tabulated histograms of the displacement, velocity, and acceleration for planar motion, and examined whether modeling of distributions could reveal changes in available movement patterns. We contrasted these results with scalar measures of the range of motion. We performed linear discriminant analysis (LDA) classification with selected histogram features to compare predictions versus actual subject identifiers. As a basis of comparison, we also present an age-matched control group of healthy individuals (n = 10, practicing for 1 day). RESULTS: Analysis of range of motion did not show improvement from self-directed movement training for the stroke survivors in this study. However, examination of distributions indicated that increased multivariate normal components were needed to accurately model the patterns of movement after training. Stroke survivors generally exhibited more complex distributions of motor exploration compared to the age-matched control group. Classification using linear discriminant analysis revealed that movement patterns were identifiable by individual. Individuals in the control group were more difficult to identify using classification methods, consistent with the idea that motor deficits contribute significantly to unique movement signatures. CONCLUSIONS: Distribution analysis revealed individual patterns of abnormal coordination in stroke survivors and changes in these patterns with training. These findings were not apparent from scalar metrics that simply summarized properties of motor exploration. Our results suggest new methods for characterizing motor capabilities, and could provide the basis for powerful tools for designing customized therapy

    Thyroid axis function after in-patient treatment of acute psychosis with antipsychotics: a naturalistic study

    No full text
    BACKGROUND: Endocrine function in psychiatric patients may be affected by mental disorder itself as well as by antipsychotic medications. The aim of this naturalistic observational study was to determine if treatment of acute psychotic episode with antipsychotic medication affects thyroid axis hormone concentrations and if such changes are associated with symptomatic improvement. METHODS: Eighty six adult acute psychotic patients, consecutively admitted to a mental hospital, were recruited for the study. All patients were physically healthy and without thyroid disease. During the hospitalization period all study patients received treatment with antipsychotic medication according to clinical need. Severity of the psychotic episode was evaluated using the Brief Psychiatric Rating Scale (BPRS) and venous blood samples were drawn for analysis of free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) concentrations on the day of admission and on the day of discharge from the hospital. RESULTS: Antipsychotic drug treatment was associated with decrease of mean FT3 (p < 0.001) and FT4 (p = 0.002) concentrations; and with increase of mean TSH (p = 0.016) concentrations. Changes in thyroid hormone concentrations were mostly predicted by baseline hormone concentrations. Individual changes were not limited to decrease in high hormone concentrations; in patients who had low FT3 or FT4 concentrations, treatment resulted in increase in concentrations. Such an increase was established in one-quarter of patients for FT3 concentrations and in one-third of patients for FT4 concentrations. Fall in FT4 concentrations negatively correlated with the improvement in the BPRS score (r = −0.235, p = 0.023). CONCLUSIONS: The study indicates that antipsychotic treatment resulted in a decrease in mean FT3 concentrations and in an increase in mean TSH concentrations after recovery from acute psychosis. Symptomatic improvement was less evident in patients who experienced a decrease in FT4 concentrations. TRIAL REGISTRATION: EudraCT No.2007-001541-1
    • 

    corecore