86 research outputs found

    The Jet and Circumnuclear Environment of 3C 293

    Full text link
    We present the new HST near-infrared polarimetry, broad and narrow-band imaging, and MERLIN 4.5GHz Multi-Frequency Synthesis radio imaging of 3C 293, a unique radio galaxy whose host is an obvious merger remnant, in an exceptionally under-dense region of space. We have discovered near-infrared, optical, and ultra-violet synchrotron emission from the jet. In the optical, the jet is mostly obscured by a dust lane, but three knots are clear in our HST NICMOS images at 1.6 and 2.0 microns, clearly aligning with features in the radio. The outer jet knot is highly polarized (~15%) at 2 microns, confirming the synchrotron emission mechanism. The radio-IR spectral index steepens significantly with distance from the nucleus, as in 3C 273 and in contrast to M 87. The inner knot is visible (with hindsight) on the WFPC2 and STIS images obtained for the earlier 3CR HST snapshot surveys. There is no [Fe II] emission seen associated with the jet, constraining the role of shock-induced ionisation by the jet. Overall there is a strong implication that the NIR jet emission is indeed synchrotron. From our NIR images, the core of the galaxy is clearly identifiable with the main feature in the western extension of the radio ``jet'' image, although no unresolved AGN component is identifiable even at K-band, consistent with an FRII-like nucleus obscured by an optically thick torus. The galaxy appears to have a single nucleus, with any multiple nuclei falling within the central </~100 pc.Comment: ApJ accepted. 31 pages, 12 figures reproduced here at low resolution. High resolution version available from http://www.stsci.edu/~floyd/BIBLIOTECA/3c293

    Longitudinal evaluation of quality of life in 288 patients with Neurofibromatosis 2

    Get PDF
    Advances in molecular biology have resulted in novel therapy for neurofibromatosis 2-related (NF2) tumours, highlighting the need for robust outcome measures. The disease-focused NF2 impact on quality of life (NFTI-QOL) patient questionnaire was assessed as an outcome measure for treatment in a multi-centre study. NFTI-QOL was related to clinician-rated severity (ClinSev) and genetic severity (GenSev) over repeated visits. Data were evaluated for 288 NF2 patients (n = 464 visits) attending the English national NF2 clinics from 2010 to 2012. The male-to-female ratio was equal and the mean age was 42.2 (SD 17.8) years. The analysis included NFTI-QOL eight-item score, ClinSev graded as mild, moderate, or severe, and GenSev as a rank order of the number of NF2 mutations (graded as mild, moderate, severe). The mean (SD) 8.7 (5.4) score for NFTI-QOL for either a first visit or all visits 9.2 (5.4) was similar to the published norm of 9.4 (5.5), with no significant relationships with age or gender. NFTI-QOL internal reliability was good, with a Cronbach’s alpha score of 0.85 and test re-test reliability r = 0.84. NFTI related to ClinSev (r = 0.41, p < 0.001; r = 0.46 for all visits), but weakly to GenSev (r = 0.16, p < 0.05; r = 0.15 for all visits). ClinSev related to GenSev (r = 0.41, p < 0.001; r = 0.42 for all visits). NFTI-QOL showed a good reliability and ability to detect significant longitudinal changes in the QOL of individuals. The moderate relationships of NFTI-QOL with clinician- and genetic-rated severity suggest that NFTI-QOL taps into NF2 patient experiences that are not encompassed by ClinSev rating or genotype

    Pitch Comparisons between Electrical Stimulation of a Cochlear Implant and Acoustic Stimuli Presented to a Normal-hearing Contralateral Ear

    Get PDF
    Four cochlear implant users, having normal hearing in the unimplanted ear, compared the pitches of electrical and acoustic stimuli presented to the two ears. Comparisons were between 1,031-pps pulse trains and pure tones or between 12 and 25-pps electric pulse trains and bandpass-filtered acoustic pulse trains of the same rate. Three methods—pitch adjustment, constant stimuli, and interleaved adaptive procedures—were used. For all methods, we showed that the results can be strongly influenced by non-sensory biases arising from the range of acoustic stimuli presented, and proposed a series of checks that should be made to alert the experimenter to those biases. We then showed that the results of comparisons that survived these checks do not deviate consistently from the predictions of a widely-used cochlear frequency-to-place formula or of a computational cochlear model. We also demonstrate that substantial range effects occur with other widely used experimental methods, even for normal-hearing listeners

    Cranial Nerve Involvement in Malignant External Otitis: Implications for Clinical Outcome

    No full text
    Mani N, Sudhoff H, Rajagopal S, Moffat D, Axon PR. Cranial Nerve Involvement in Malignant External Otitis: Implications for Clinical Outcome. The Laryngoscope. 2007;117(5):907-910

    Preoperative Audiovestibular Handicap in Patients with Vestibular Schwannoma

    No full text
    Objectives: To evaluate preoperative hearing, dizziness, and tinnitus handicap in patients with unilateral vestibular schwannoma (VS). Design: Prospective administration of the Hearing Handicap Inventory (HHI), Dizziness Handicap Inventory (DHI), and Tinnitus Handicap Inventory (THI), prior to surgical intervention. Setting: A tertiary referral neuro-otology clinic. Participants: A total of 145 consecutive patients who were admitted for excision of their vestibular schwannomas between May 1998 and July 2002. Main Outcome Measures: HHI, THI, and DHI scores. Results: HHI, THI, and DHI scores were all found to be significantly correlated. There was no significant association between tumor size and any of the questionnaire scores. When data were categorized to give a measure of handicap severity, 68% had mild to significant hearing handicap, 30% had mild to severe tinnitus handicap, and 75% had mild to severe dizziness handicap. Eighty-eight percent of patients had some handicap in at least one domain, and 23% had some handicap in all three domains. Seven percent of patients had severe or significant handicap in all three domains. Conclusions: A considerable proportion of patients with unilateral VS have hearing, tinnitus, and dizziness handicap. These patients should optimally be offered appropriate rehabilitation, something that is especially important as conservative management by “watch, wait, and rescan” becomes more common
    • 

    corecore