9,435 research outputs found

    Local and global limits on visual processing in schizophrenia.

    Get PDF
    Schizophrenia has been linked to impaired performance on a range of visual processing tasks (e.g. detection of coherent motion and contour detection). It has been proposed that this is due to a general inability to integrate visual information at a global level. To test this theory, we assessed the performance of people with schizophrenia on a battery of tasks designed to probe voluntary averaging in different visual domains. Twenty-three outpatients with schizophrenia (mean age: 40±8 years; 3 female) and 20 age-matched control participants (mean age 39±9 years; 3 female) performed a motion coherence task and three equivalent noise (averaging) tasks, the latter allowing independent quantification of local and global limits on visual processing of motion, orientation and size. All performance measures were indistinguishable between the two groups (ps>0.05, one-way ANCOVAs), with one exception: participants with schizophrenia pooled fewer estimates of local orientation than controls when estimating average orientation (p = 0.01, one-way ANCOVA). These data do not support the notion of a generalised visual integration deficit in schizophrenia. Instead, they suggest that distinct visual dimensions are differentially affected in schizophrenia, with a specific impairment in the integration of visual orientation information

    Medieval London: Collected Papers of Caroline M. Barron

    Get PDF
    Caroline M. Barron is the world\u27s leading authority on the history of medieval London. For half a century she has investigated London\u27s role as medieval England\u27s political, cultural, and commercial capital, together with the urban landscape and the social, occupational, and religious cultures that shaped the lives of its inhabitants. This collection of eighteen papers focuses on four themes: crown and city; parish, church, and religious culture; the people of medieval London; and the city\u27s intellectual and cultural world. They represent essential reading on the history of one of the world\u27s greatest cities by its foremost scholar.https://scholarworks.wmich.edu/mip_rmemc/1009/thumbnail.jp

    Voltage-independent SK-channel dysfunction causes neuronal hyperexcitability in the hippocampus of Fmr1 knock-out mice

    Get PDF
    Neuronal hyperexcitability is one of the major characteristics of fragile X syndrome (FXS), yet the molecular mechanisms of this critical dysfunction remain poorly understood. Here we report a major role of voltage-independent potassium (

    Fear and Loathing in Las Vegas: Evidence from Blackjack Tables

    Get PDF
    Psychologists study regret primarily by measuring subjects' attitudes in laboratory experiments. This does not shed light on how expected regret affects economic actions in market settings. To address this, we use proprietary data from a blackjack table in Las Vegas to analyze how expected regret affects peoples''decisions during gambles. Even among a group of people who choose to participate in a risk-taking activity, we find strong evidence of an economically significant omission bias: players incur substantial losses by playing too conservatively. This behavior is prevalent even among large stakes gamblers, and becomes more severe following previous aggressive play, suggesting a rebound effect after aggressive play.

    Cavity-enhanced optical Hall effect in two-dimensional free charge carrier gases detected at terahertz frequencies

    Full text link
    The effect of a tunable, externally coupled Fabry-P\'{e}rot cavity to resonantly enhance the optical Hall effect signatures at terahertz frequencies produced by a traditional Drude-like two-dimensional electron gas is shown and discussed in this communication. As a result, the detection of optical Hall effect signatures at conveniently obtainable magnetic fields, for example by neodymium permanent magnets, is demonstrated. An AlInN/GaN-based high electron mobility transistor structure grown on a sapphire substrate is used for the experiment. The optical Hall effect signatures and their dispersions, which are governed by the frequency and the reflectance minima and maxima of the externally coupled Fabry-P\'{e}rot cavity, are presented and discussed. Tuning the externally coupled Fabry-P\'{e}rot cavity strongly modifies the optical Hall effect signatures, which provides a new degree of freedom for optical Hall effect experiments in addition to frequency, angle of incidence and magnetic field direction and strength

    Arkansas Wheat Performance Tests 2023-2024

    Get PDF
    Wheat variety performance tests are conducted each year in Ark- ansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program. The tests provide information to companies developing cultivars and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for small-grain producers. The tests were conducted at the Northeast Research and Extension Center at Keiser, the Vegetable Substation near Kibler, the Lon Mann Cotton Research Station near Marianna, the Pine Tree Research Station near Colt, and the Rohwer Research Station near Rohwer. Specific location and cultural practice information accompany each table

    On class visualisation for high dimensional data: Exploring scientific datasets

    Get PDF
    Parametric Embedding (PE) has recently been proposed as a general-purpose algorithm for class visualisation. It takes class posteriors produced by a mixture-based clustering algorithm and projects them in 2D for visualisation. However, although this fully modularised combination of objectives (clustering and projection) is attractive for its conceptual simplicity, in the case of high dimensional data, we show that a more optimal combination of these objectives can be achieved by integrating them both into a consistent probabilistic model. In this way, the projection step will fulfil a role of regularisation, guarding against the curse of dimensionality. As a result, the tradeoff between clustering and visualisation turns out to enhance the predictive abilities of the overall model. We present results on both synthetic data and two real-world high-dimensional data sets: observed spectra of early-type galaxies and gene expression arrays.Comment: to appear in Lecture notes in Artificial Intelligence vol. 4265, the (refereed) proceedings of the Ninth International conference on Discovery Science (DS-2006), October 2006, Barcelona, Spain. 12 pages, 8 figure

    Thermal and magnetic properties of spin-1 magnetic chain compounds with large single-ion and in-plane anisotropies

    Full text link
    The thermal and magnetic properties of spin-1 magnetic chain compounds with large single-ion and in-plane anisotropies are investigated via the integrable su(3) model in terms of the quantum transfer matrix method and the recently developed high temperature expansion method for exactly solved models. It is shown that large single-ion anisotropy may result in a singlet gapped phase in the spin-1 chain which is significantly different from the standard Haldane phase. A large in-plane anisotropy may destroy the gapped phase. On the other hand, in the vicinity of the critical point a weak in-plane anisotropy leads to a different phase transition than the Pokrovsky-Talapov transition. The magnetic susceptibility, specific heat and magnetization evaluated from the free energy are in excellent agreement with the experimental data for the compounds NiC_2H_8N_2)_2Ni(CN)_4 and Ni(C_{10}H_8N_2)_2Ni(CN)_4.H_2O.Comment: 18 pages, 6 figures, to appear in PR
    corecore