206 research outputs found

    Fear Reduction Processes in Imaginal and In Vivo Flooding: A Comment on James\u27 Review

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    The research comparing imaginal and in vivo exposure in the treatment of clinically significant fear, recently reviewed by James (1986), is reexamined from the perspective of bioinformational theory and the concept of emotional processing. Fear is assumed to be stored in long term memory as a network of propositionally-coded information, which has to be processed if treatment is to be successful. Emotional processing is indicated by activation of fear responses and their habituation within and across treatment sessions. Consistent with the theory, our review indicates that successful treatment via imaginal and in vivo exposure is indeed related to activation and habituation of fear responses; interference with processing has a negative impact upon fear reduction, regardless of the specific treatment techniques employed. Furthermore, some apparently discrepant findings in the available research literature can be understood in terms of the theories cited. These ideas provide a useful perspective from which to plan future research efforts and to advance our understanding of the processes underlying reduction of pathological fear

    System and method for tuning adjusting the central frequency of a laser while maintaining frequency stabilization to an external reference

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    A method and system for stabilizing a laser to a frequency reference with an adjustable offset. The method locks a sideband signal generated by passing an incoming laser beam through the phase modulator to a frequency reference, and adjusts a carrier frequency relative to the locked sideband signal by changing a phase modulation frequency input to the phase modulator. The sideband signal can be a single sideband (SSB), dual sideband (DSB), or an electronic sideband (ESB) signal. Two separate electro-optic modulators can produce the DSB signal. The two electro-optic modulators can be a broadband modulator and a resonant modulator. With a DSB signal, the method can introduce two sinusoidal phase modulations at the phase modulator. With ESB signals, the method can further drive the optical phase modulator with an electrical signal with nominal frequency OMEGA(sub 1) that is phase modulated at a frequency OMEGA(sub 2

    Insight Versus Rehearsal in Cognitive-Behavior Therapy: A Crossover Study with Sixteen Phobics

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    Although cognitive restructuring (CR) procedures have not proven very helpful for phobics in recent studies, insight and rehearsal components of CR have often been confounded. To seek possible differences in effectiveness between insight and rehearsal, we treated 16 phobics (eight agoraphobics and eight others) with four sessions of each method, using a counterbalanced crossover design with 1-month follow-ups after each treatment component. Significantly fewer sessions were attended by the clients in the rehearsal/insight sequence, and benefit ratings made by project completers significantly favoured insight/rehearsal. Few other treatment group differences were seen, but those that emerged gave the advantage to insight. Rehearsal seemed unhelpful, particularly to non-agoraphobics. Conclusions are (1) that CR methods show some promise in application to phobias, provided that self-exposure homework forms the core of the treatment plan, and (2) that insight followed by rehearsal is the preferred sequence

    On rapid interstellar scintillation of quasars: PKS 1257-326 revisited

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    The line of sight towards the compact, radio loud quasar PKS 1257-326 passesthrough a patch of scattering plasma in the local Galactic ISM that causes large and rapid,intra-hour variations in the received flux density at centimetre wavelengths. This rapid interstellarscintillation (SS) has been occurring for at least 15 years, implying that the scattering“screen” is at least 100 AU in physical extent. Through observations of the ISS we have measuredmicroarcsecond-scale “core shifts” in PKS 1257-326, corresponding to changing opacityduring an intrinsic outburst. Recent analysis of VLA data of a sample of 128 quasars found 6sources scintillating with a characteristic time-scale of < 2 hours, suggesting that nearby scatteringscreens in the ISM may have a covering fraction of a few percent. That is an importantconsideration for proposed surveys of the transient and variable radio sk

    Improving chronic disease prevention and screening in primary care: results of the BETTER pragmatic cluster randomized controlled trial.

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    BackgroundPrimary care provides most of the evidence-based chronic disease prevention and screening services offered by the healthcare system. However, there remains a gap between recommended preventive services and actual practice. This trial (the BETTER Trial) aimed to improve preventive care of heart disease, diabetes, colorectal, breast and cervical cancers, and relevant lifestyle factors through a practice facilitation intervention set in primary care.MethodsPragmatic two-way factorial cluster RCT with Primary Care Physicians' practices as the unit of allocation and individual patients as the unit of analysis. The setting was urban Primary Care Team practices in two Canadian provinces. Eight Primary Care Team practices were randomly assigned to receive the practice-level intervention or wait-list control; 4 physicians in each team (32 physicians) were randomly assigned to receive the patient-level intervention or wait-list control. Patients randomly selected from physicians' rosters were stratified into two groups: 1) general and 2) moderate mental illness. The interventions involved a multifaceted, evidence-based, tailored practice-level intervention with a Practice Facilitator, and a patient-level intervention involving a one-hour visit with a Prevention Practitioner where patients received a tailored 'prevention prescription'. The primary outcome was a composite Summary Quality Index of 28 evidence-based chronic disease prevention and screening actions with pre-defined targets, expressed as the ratio of eligible actions at baseline that were met at follow-up. A cost-effectiveness analysis was conducted.Results789 of 1,260 (63%) eligible patients participated. On average, patients were eligible for 8.96 (SD 3.2) actions at baseline. In the adjusted analysis, control patients met 23.1% (95% CI: 19.2% to 27.1%) of target actions, compared to 28.5% (95% CI: 20.9% to 36.0%) receiving the practice-level intervention, 55.6% (95% CI: 49.0% to 62.1%) receiving the patient-level intervention, and 58.9% (95% CI: 54.7% to 63.1%) receiving both practice- and patient-level interventions (patient-level intervention versus control, P < 0.001). The benefit of the patient-level intervention was seen in both strata. The extra cost of the intervention was 26.43CAN(9526.43CAN (95% CI: 16 to $44) per additional action met.ConclusionsA Prevention Practitioner can improve the implementation of clinically important prevention and screening for chronic diseases in a cost-effective manner

    DO IT Trial: vitamin D Outcomes and Interventions in Toddlers - a TARGet Kids! randomized controlled trial.

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    BackgroundVitamin D levels are alarmingly low (<75 nmol/L) in 65-70% of North American children older than 1 year. An increased risk of viral upper respiratory tract infections (URTI), asthma-related hospitalizations and use of anti-inflammatory medication have all been linked with low vitamin D. No study has determined whether wintertime vitamin D supplementation can reduce the risk of URTI and asthma exacerbations, two of the most common and costly illnesses of early childhood. The objectives of this study are: 1) to compare the effect of 'high dose' (2000 IU/day) vs. 'standard dose' (400 IU/day) vitamin D supplementation in achieving reductions in laboratory confirmed URTI and asthma exacerbations during the winter in preschool-aged Canadian children; and 2) to assess the effect of 'high dose' vitamin D supplementation on vitamin D serum levels and specific viruses that cause URTI.Methods/designThis study is a pragmatic randomized controlled trial. Over 4 successive winters we will recruit 750 healthy children 1-5 years of age. Participating physicians are part of a primary healthcare research network called TARGet Kids!. Children will be randomized to the 'standard dose' or 'high dose' oral supplemental vitamin D for a minimum of 4 months (200 children per group). Parents will obtain a nasal swab from their child with each URTI, report the number of asthma exacerbations and complete symptom checklists. Unscheduled physician visits for URTIs and asthma exacerbations will be recorded. By May, a blood sample will be drawn to determine vitamin D serum levels. The primary analysis will be a comparison of URTI rate between study groups using a Poisson regression model. Secondary analyses will compare vitamin D serum levels, asthma exacerbations and the frequency of specific viral agents between groups.DiscussionIdentifying whether vitamin D supplementation of preschoolers can reduce wintertime viral URTIs and asthma exacerbations and what dose is optimal may reduce population wide morbidity and associated health care and societal costs. This information will assist in determining practice and health policy recommendations related to vitamin D supplementation in healthy Canadian preschoolers

    Frequency-Tunable Pre-stabilized lasers for LISA via Stabilized Lasers for LISA via Sideband Locking

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    This viewgraph presentation discusses a major potential source of noise for the Laser Interferometer Space Antenna (LISA) that is the laser frequency noise and the proposed mechanism to suppress the unstabilized frequency fluctuations. These fluctuations must be suppresed by about 12 orders of magnitude to achieve a stability that is sufficient for the detection of gravitational waves. This presentation reviews present a modification to the traditional cavity locking technique that allows the laser to be locked to a cavity resonance with an adjustable frequency offset. This presentation also discusses measurements of the system stability, demonstrating that the pre-stabilization level satisfies LISA requirements and a demonstration of a phase-lock loop which utilizes the tunable sideband locking technique as a pre-stabilization stage

    Laser Frequency Stabilization

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    Laser ranging and interferometry are essential technologies allowing for many astounding new spacebased missions such as the Laser Interferometer Space Antenna (LISA) to measure gravitational radiation emitted from distant super massive black hole mergers or distributed aperture telescopes with unprecedented angular resolution in the NIR or visible regime. The requirements on laser frequency noise depend on the residual motion and the distances between the spacecraft forming the interferometer. The intrinsic frequency stability of commercial lasers is several orders of magnitude above these requirements. Therefore, it is necessary for lasers to be stabilized to an ultrastable frequency reference so that they can be used to sense and control distances between spacecraft. Various optical frequency references and frequency stabilization schemes are considered and investigated for the applicability and usefulness for space-based interferometry missions

    Cell Furniture: Designs for Safety, Wellbeing, and Sustainability

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    This catalogue presents the outcomes of a project aimed at creating a new line of prison furniture that not only prioritises robustness and sustainability but also strives to enhance the well-being of both prisoners and prison staff. To do this, a collaborative design approach involving stakeholders with diverse experiences was delivered. Drawing on research conducted with prisoners, officers, and external stakeholders, the project addressed complex issues related to furniture use in prisons. The project aimed to enhance existing furniture while introducing new, sustainable designs to the current selection. We hope that these new concepts and designs have potential to be manufactured inside the prison

    Frequency-tunable Pre-stabilized Lasers for LISA via Sideband-locking

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    Laser frequency noise mitigation is one of the most challenging aspects of the LISA interferometric measurement system. The unstabilized frequency fluctuations must be suppressed by roughly twelve orders of magnitude in order to achieve stability sufficient for gravitational wave detection. This enormous suppression will be achieved through a combination of stabilization and common-mode rejection. The stabilization component will itself be achieved in two stages: pre-stabilization to a local optical cavity followed by arm-locking to some combination of the inter-spacecraft distances. In order for these two stabilization stages to work simultaneously, the lock-point of the pre-stabilization loop must be frequency tunable. The current baseline stabilization technique, locking to an optical cavity, does not provide tunability between cavity resonances, which are typically spaced by 100s of MHz. Here we present a modification to the traditional Pound-Drever-Hall cavity locking technique that allows the laser to be locked to a cavity resonance with an adjustable frequency offset. This technique requires no modifications to the optical cavity itself, thus preserving the stability of the frequency reference. We present measurements of the system performance and demonstrate that we can meet implement the first two stages of stabilization
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