1,212 research outputs found

    SGARFACE: A Novel Detector For Microsecond Gamma Ray Bursts

    Full text link
    The Short GAmma Ray Front Air Cherenkov Experiment (SGARFACE) is operated at the Whipple Observatory utilizing the Whipple 10m gamma-ray telescope. SGARFACE is sensitive to gamma-ray bursts of more than 100MeV with durations from 100ns to 35us and provides a fluence sensitivity as low as 0.8 gamma-rays per m^2 above 200MeV (0.05 gamma-rays per m^2 above 2GeV) and allows to record the burst time structure.Comment: 29 pages, 14 figures, accepted for publication in Astroparticle Physic

    A New Analysis Method for Reconstructing the Arrival Direction of TeV Gamma-rays Using a Single Imaging Atmospheric Cherenkov Telescope

    Get PDF
    We present a method of atmospheric Cherenkov imaging which reconstructs the unique arrival direction of TeV gamma rays using a single telescope. The method is derived empirically and utilizes several features of gamma-ray induced air showers which determine, to a precision of 0.12 degrees, the arrival direction of photons, on an event-by-event basis. Data from the Whipple Observatory's 10 m gamma-ray telescope is utilized to test selection methods based on source location. The results compare these selection methods with traditional techniques and three different camera fields of view. The method will be discussed in the context of a search for a gamma-ray signal from a point source located anywhere within the field of view and from regions of extended emission.Comment: 24 pages, 16 figures, accepted for publication in Astroparticle Physics May 11, 200

    Memory for serial order in bilingual children

    Get PDF
    Poster: no. 10Recent studies have suggested that phonological short-term memory (STM) capacity is important for language acquisition. In both, children and grownups, reliable correlations have been obtained between digit span, nonword repetition ability, and vocabulary achievement while factoring out other possible factors like age and nonverbal intelligence (Gathercole, Service, Hitch, Adams, & Martin, 1999; Gathercole, Willis, Emslie, & Baddeley, 1992; Gupta, 2003). Majerus et al. (Majerus, Poncelet, Van der Linden, & Weekes, 2008) found that serial order memory was the most important predictor for new word learning. No evidence was found for item short-term memory as a predictor. Majerus et al. therefore suggested that order short-term memory and phonological awareness are independent predictors of new word learning. Our aim was to investigate the memory for serial order in mono- and bilingual language processing to elicit ERP correlates of item and order STM, during encoding, maintenance and retrieval stages. 25 monolingual native English speakers 
postprintThe International Conference on Neurobilingualism, Bangor University, Wales, U.K., 19-20 September 2009

    Minimal Stereoscopic Analysis for Imaging Atmospheric Cherenkov Telescope Arrays

    Get PDF
    The trajectory of a primary gamma-ray detected with an array of at least four atmospheric Cherenkov imaging telescopes can be reconstructed from the shower image centroid positions and geometrical considerations independent of the primary energy. Using only the image centroid positions some cosmic-ray discrimination is also possible. This minimal approach opens the possibility of pushing the analysis threshold to lower values, close to the hardware threshold

    How are affective word ratings related to lexicosemantic properties?:evidence from the Sussex Affective Word List

    Get PDF
    Emotional content of verbal material affects the speed of visual word recognition in various cognitive tasks, independently of lexicosemantic variables. However, little is known about how the dimensions of emotional arousal and valence interact with the lexicosemantic properties of words such as age of acquisition, familiarity, and imageability, that determine word recognition performance. This study aimed to examine these relationships using English ratings for affective and lexicosemantic features. Eighty-two native English speakers rated 300 words for emotional valence, arousal, familiarity, age of acquisition, and imageability. Although both dimensions of emotion were correlated with lexicosemantic variables, a unique emotion cluster produced the strongest quadratic relationship. This finding suggests that emotion should be included in models of word recognition as it is likely to make an independent contribution

    Detection Techniques of Microsecond Gamma-Ray Bursts using Ground-Based Telescopes

    Get PDF
    Gamma-ray observations above 200 MeV are conventionally made by satellite-based detectors. The EGRET detector on the Compton Gamma Ray Observatory (CGRO) has provided good sensitivity for the detection of bursts lasting for more than 200 ms. Theoretical predictions of high-energy gamma-ray bursts produced by quantum-mechanical decay of primordial black holes (Hawking 1971) suggest the emission of bursts on shorter time scales. The final stage of a primordial black hole results in a burst of gamma-rays, peaking around 250 MeV and lasting for a tenth of a microsecond or longer depending on particle physics. In this work we show that there is an observational window using ground-based imaging Cherenkov detectors to measure gamma-ray burst emission at energies E greater than 200 MeV. This technique, with a sensitivity for bursts lasting nanoseconds to several microseconds, is based on the detection of multi-photon-initiated air showers.Comment: accepted for publication in the Astrophysical Journa

    Using the ‘recovery’ and ‘rehabilitation’ paradigms to support desistence of substance-involved offenders: Exploration of dual and multi-focus interventions (Invited Paper)

    Get PDF
    Purpose The links between substance use and offending are well evidenced in the literature, and increasingly, substance misuse recovery is being seen as a central component of the process of rehabilitation from offending, with substance use identified as a key criminogenic risk factor. In recent years, research has demonstrated the commonalities between recovery and rehabilitation, and the possible merits of providing interventions to substance-involved offenders that address both problematic sets of behaviours. The purpose of this paper is to provide an overview of the links between substance use and offending, and the burgeoning literature around the parallel processes of recovery and rehabilitation. Design/methodology/approach This is provided as a rationale for a new treatment approach for substance-involved offenders, Breaking Free Online (BFO), which has recently been provided as part of the “Gateways” throughcare pathfinder in a number of prisons in North-West England. The BFO programme contains specific behaviour change techniques that are generic enough to be applied to change a wide range of behaviours, and so is able to support substance-involved offenders to address their substance use and offending simultaneously. Findings This dual and multi-target intervention approach has the potential to address multiple, associated areas of need simultaneously, streamlining services and providing more holistic support for individuals, such as substance-involved offenders, who may have multiple and complex needs. Practical implications Given the links between substance use and offending, it may be beneficial to provide multi-focussed interventions that address both these behaviours simultaneously, in addition to other areas of multiple and complex needs. Specifically, digital technologies may provide an opportunity to widen access to such multi-focussed interventions, through computer-assisted therapy delivery modalities. Additionally, using digital technologies to deliver such interventions can provide opportunities for joined-up care by making interventions available across both prison and community settings, following offenders on their journey through the criminal justice system. Originality/value Recommendations are provided to other intervention developers who may wish to further contribute to widening access to such dual- and multi-focus programmes for substance-involved offenders, based on the experiences developing and evidencing the BFO programme

    TOPSAN: a dynamic web database for structural genomics

    Get PDF
    The Open Protein Structure Annotation Network (TOPSAN) is a web-based collaboration platform for exploring and annotating structures determined by structural genomics efforts. Characterization of those structures presents a challenge since the majority of the proteins themselves have not yet been characterized. Responding to this challenge, the TOPSAN platform facilitates collaborative annotation and investigation via a user-friendly web-based interface pre-populated with automatically generated information. Semantic web technologies expand and enrich TOPSAN’s content through links to larger sets of related databases, and thus, enable data integration from disparate sources and data mining via conventional query languages. TOPSAN can be found at http://www.topsan.org

    Effects of valence and arousal on written word recognition:Time course and ERP correlates

    Get PDF
    Models of affect assume a two-dimensional framework, composed of emotional valence and arousal. Although neuroimaging evidence supports a neuro-functional distinction of their effects during single word processing, electrophysiological studies have not yet compared the effects of arousal within the same category of valence (positive and negative). Here we investigate effects of arousal and valence on written lexical decision. Amplitude differences between emotion and neutral words were seen in the early posterior negativity (EPN), the late positive complex and in a sustained slow positivity. In addition, trends towards interactive effects of valence and arousal were observed in the EPN, showing larger amplitude for positive, high-arousal and negative, low-arousal words. The results provide initial evidence for interactions between arousal and valence during processing of positive words and highlight the importance of both variables in studies of emotional stimulus processing. Crown Copyright (C) 2012 Published by Elsevier Ireland Ltd. All rights reserved
    • 

    corecore