819 research outputs found

    Stimulus - response curves of a neuronal model for noisy subthreshold oscillations and related spike generation

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    We investigate the stimulus-dependent tuning properties of a noisy ionic conductance model for intrinsic subthreshold oscillations in membrane potential and associated spike generation. On depolarization by an applied current, the model exhibits subthreshold oscillatory activity with occasional spike generation when oscillations reach the spike threshold. We consider how the amount of applied current, the noise intensity, variation of maximum conductance values and scaling to different temperature ranges alter the responses of the model with respect to voltage traces, interspike intervals and their statistics and the mean spike frequency curves. We demonstrate that subthreshold oscillatory neurons in the presence of noise can sensitively and also selectively be tuned by stimulus-dependent variation of model parameters.Comment: 19 pages, 7 figure

    Spectrum and Variability of Mrk501 as observed by the CAT Imaging Telescope

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    The CAT Imaging Telescope has observed the BL Lac object Markarian 501 between March and August 1997. We report here on the variability over this time including several large flares. We present also preliminary spectra for all these data, for the low emission state, and for the largest flare.Comment: 4 pages, 4 figures, Late

    Observation of the Crab Nebula Gamma-Ray Emission Above 220 Gev by the Cat Cherenkov Imaging Telescope

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    The CAT imaging telescope, recently built on the site of the former solar plant Themis (French Pyrenees), observed gamma-rays from the Crab nebula from October 1996 to March 1997. This steady source, often considered as the standard candle of very-high-energy gamma-ray astronomy, is used as a test-beam to probe the performances of the new telescope, particularly its energy threshold (220 GeV at 20 degrees zenith angle) and the stability of its response. Due to the fine-grain camera, an accurate analysis of the longitudinal profiles of shower images is performed, yielding the source position in two dimensions for each individual shower.Comment: 5 pages, 3 figures, Tex, contribution to 25th ICRC Durba

    Detection of Vhe Gamma-Rays from MRK 501 with the Cat Imaging Telescope

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    The CAT imaging telescope on the site on the former solar plant Themis has been observing gamma-rays from Mrk501 above 220 GeV in March and April 1997. This source is shown to be highly variable and the light curve is presented. The detected gamma-ray rate for the most intense flare is in excess of 10 per minute.Comment: 5 pages, 4 figures, Tex, contribution to 25th ICRC Durba

    Chapter 7: Wetlands

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    Contains fulltext : 205862.pdf (publisher's version ) (Open Access

    The implementation evaluation of primary care groups of practice: a focus on organizational identity

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    <p>Abstract</p> <p>Background</p> <p>Since 2002 the Health Ministry of Québec (Canada) has been implementing a primary care organizational innovation called 'family medicine groups'. This is occurring in a political context in which the reorganization of primary care is considered necessary to improve health care system performance. More specifically, the purpose of this reform has been to overcome systemic deficiencies in terms of accessibility and continuity of care. This paper examines the first years of implementation of the family medicine group program, with a focus on the emergence of the organizational identity of one of the pilot groups located in the urban area of Montreal.</p> <p>Methods</p> <p>An in-depth longitudinal case study was conducted over two and a half years. Face to face individual interviews with key informants from the family medicine group under study were conducted over the research period considered. Data was gathered throuhg observations and documentary analysis. The data was analyzed using temporal bracketing and Fairclough's three-dimensional critical discourse analytical techniques.</p> <p>Results</p> <p>Three different phases were identified over the period under study. During the first phase, which corresponded to the official start-up of the family medicine group program, new resources and staff were only available at the end of the period, and no changes occurred in medical practices. Power struggles between physicians and nurses characterized the second phase, resulting in a very difficult integration of advanced nurse practitioners into the group. Indeed, the last phase was portrayed by initial collaborative practices associated with a sensegiving process prompted by a new family medicine group director.</p> <p>Conclusions</p> <p>The creation of a primary care team is a very challenging process that goes beyond the normative policy definitions of who is on the team or what the team has to do. To fulfil expectations of quality improvement through team-based care, health care professionals who are required to work together need shared time/space contexts to communicate; to overcome interprofessional and interpersonal conflicts; and to make sense of and define who they collectively are and what they do as a clinical team.</p

    Assessment of a primary care-based telemonitoring intervention for home care patients with heart failure and chronic lung disease. The TELBIL study

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    <p>Abstract</p> <p>Background</p> <p>Telemonitoring technology offers one of the most promising alternatives for the provision of health care services at the patient's home. The primary aim of this study is to evaluate the impact of a primary care-based telemonitoring intervention on the frequency of hospital admissions.</p> <p>Methods/design</p> <p>A primary care-based randomised controlled trial will be carried out to assess the impact of a telemonitoring intervention aimed at home care patients with heart failure (HF) and/or chronic lung disease (CLD). The results will be compared with those obtained with standard health care practice. The duration of the study will be of one year. Sixty patients will be recruited for the study. In-home patients, diagnosed with HF and/or CLD, aged 14 or above and with two or more hospital admissions in the previous year will be eligible.</p> <p>For the intervention group, telemonitoring will consist of daily patient self-measurements of respiratory-rate, heart-rate, blood pressure, oxygen saturation, weight and body temperature. Additionally, the patients will complete a qualitative symptom questionnaire daily using the telemonitoring system. Routine telephone contacts will be conducted every fortnight and additional telephone contacts will be carried out if the data received at the primary care centre are out of the established limits. The control group will receive usual care. The primary outcome measure is the number of hospital admissions due to any cause that occurred in a period of 12 months post-randomisation. The secondary outcome measures are: duration of hospital stay, hospital admissions due to HF or CLD, mortality rate, use of health care resources, quality of life, cost-effectiveness, compliance and patient and health care professional satisfaction with the new technology.</p> <p>Discussion</p> <p>The results of this study will shed some light on the effects of telemonitoring for the follow-up and management of chronic patients from a primary care setting. The study may contribute to enhance the understanding of alternative modes of health care provision for medically unstable elderly patients, who bear a high degree of physical and functional deterioration.</p> <p>Trial Registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN89041993">ISRCTN89041993</a></p
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