Polysemy in the mental lexicon: relatedness and frequency affect representational overlap

Meaning relatedness affects storage of ambiguous words in the mental lexicon: unrelated meanings(homonymy) are stored separately whereas related senses (polysemy) are stored as one large representational entry. We hypothesised that word frequency could have similar effects on storage, with low-frequency words having high representational overlap and high-frequency words having low representational overlap. Participants performed lexical decision or semantic categorisation to high- and low-frequency nouns with few and many senses. Results showed a three-way interaction between frequency, task type, and polysemy. Low-frequency words showed a polysemy advantage with lexical decision but a polysemy disadvantage with semantic categorisation, whereas high-frequency words showed the opposite pattern. These results confirmed our hypothesis that relatedness and word frequency have similar effects on storage of ambiguous words

Effect of quantum noise on Coulomb blockade in normal tunnel junctions at high voltages

We have investigated asymptotic behavior of normal tunnel junctions at voltages where even the best ohmic environments start to look like RC transmission lines. In the experiments, this is manifested by an exceedingly slow approach to the linear behavior above the Coulomb gap. As expected on the basis of the quantum theory taking into account interaction with the environmental modes, better fits are obtained using 1/sqrt{V}- than 1/V- dependence for the asymptote. These results agree with the horizon picture if the frequency-dependent phase velocity is employed instead of the speed of light in order to determine the extent of the surroundings seen by the junction.Comment: 9 pages, 4 figures, submitted to Phys. Rev.

Visualising speech : using ultrasound to diagnose and treat speech disorders in children with cleft lip and palate

BACKGROUND: Children with cleft lip and palate (CLP) often continue to have problems producing clear speech long after the clefts have been surgically repaired, leading to educational and social disadvantage. Speech is of key importance in CLP from both a quality of life and surgical outcome perspective, yet assessment relies on subjective perceptual methods, namely phonetic transcription. This is particularly problematic in CLP where the range of error types is arguably far greater than for other speech sound disorders, leading to problems with reliability (Howard & Lohmander, 2011). Moreover, CLP speech is known to be vulnerable to imperceptible error types, such as double articulations which can only be understood with instrumental techniques. Incorrect transcription of these errors can result in misdiagnosis and subsequent inappropriate intervention which can lead to speech errors becoming deeply ingrained. Until now, the technique of choice (recommended by the UK professional body for Speech & Language Therapists) for assessing articulatory errors in CLP has been electropalatography, with a number of small n studies showing it to be a powerful technique for identifying imperceptible errors and treating them by using real-time EPG for biofeedback. However, EPG is expensive and logistically difficult to manage. In contrast, ultrasound is cheaper and arguably better equipped to image the posterior articulations (such as pharyngeals) which are common in CLP. This study will present an ultrasound assessment protocol for the assessment of CLP speech which is designed to dovetail with current assessment practices used in Europe. Methods: We will use UTI to both qualitatively and quantitatively identify errors in the speech of 40 children with CLP. Data will consist of materials from the CLEFTNET protocol: spontaneous counting, 10 repetitions of all consonants in /aCa/, sentences from GOS.SP.ASS. 98 (Sell, Harding & Grunwell, 1998) and 5 minimal sets contrasting common substitutions (e.g. “a ship, a sip, a chip”). Ultrasound data will be collected using a Sonospeech high-speed cineloop system at 80fps over a 150 degree field of view. The ultrasound probe will be placed under the chin using a new lightweight stabilising head set. Analysis: Consonants will be annotated using Articulate Assistant Advanced (AAA) software (Articulate Instruments, 2012), after which we will systematically analyse the data to identify each of Gibbon’s eight error types (Gibbon, 2004) using measures by Zharkova (2013, 2016) and Dawson, Tiede and Whalen (2016).Conclusions: Data collection is ongoing. This poster will present the protocol for the study and some preliminary data demonstrating cleft-type speech characteristics which can be identified using ultrasound

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters