2,566 research outputs found

    On the Choice of Prior in Bayesian Model Averaging

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    Bayesian model averaging attempts to combine parameter estimation and model uncertainty in one coherent framework. The choice of prior is then critical. Within an explicit framework of ignorance we define a ‘suitable’ prior as one which leads to a continuous and suitable analog to the pretest estimator. The normal prior, used in standard Bayesian model averaging, is shown to be unsuitable. The Laplace (or lasso) prior is almost suitable. A suitable prior (the Subbotin prior) is proposed and its properties are investigated.Model averaging;Bayesian analysis;Subbotin prior

    No Evidence Supporting Flare Driven High-Frequency Global Oscillations

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    The underlying physics that generates the excitations in the global low-frequency, < 5.3 mHz, solar acoustic power spectrum is a well known process that is attributed to solar convection; However, a definitive explanation as to what causes excitations in the high-frequency regime, > 5.3 mHz, has yet to be found. Karoff and Kjeldsen (Astrophys. J. 678, 73-76, 2008) concluded that there is a correlation between solar flares and the global high-frequency solar acoustic waves. We have used the Global Oscillations Network Group (GONG) helioseismic data in an attempt to verify Karoff and Kjeldsen (2008) results as well as compare the post-flare acoustic power spectrum to the pre-flare acoustic power spectrum for 31 solar flares. Among the 31 flares analyzed, we observe that a decrease in acoustic power after the solar flare is just as likely as an increase. Furthermore, while we do observe variations in acoustic power that are most likely associated with the usual p-modes associated with solar convection, these variations do not show any significant temporal association with flares. We find no evidence that consistently supports flare driven high-frequency waves.Comment: 20 pages, 9 figures, Accepted for publication in Solar Physic

    Pyrrolo- and pyridomorphinans:Non-selective opioid antagonists and delta opioid agonists/mu opioid partial agonists

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    Opioid ligands have found use in a number of therapeutic areas, including for the treatment of pain and opiate addiction (using agonists) and alcohol addiction (using antagonists such as naltrexone and nalmefene). The reaction of imines, derived from the opioid ligands oxymorphone and naltrexone, with Michael acceptors leads to pyridomorphinans with structures similar to known pyrrolo- and indolomorphinans. One of the synthesized compounds, 5e, derived from oxymorphone had substantial agonist activity at delta opioid receptors but not at mu and/or kappa opioid receptors and in that sense profiled as a selective delta opioid receptor agonist. The pyridomorphinans derived from naltrexone and naloxone were all found to be non-selective potent antagonists and as such could have utility as treatments for alcohol abuse

    Consistent Truncation to Three Dimensional (Super-)gravity

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    For a general three dimensional theory of (super-)gravity coupled to arbitrary matter fields with arbitrary set of higher derivative terms in the effective action, we give an algorithm for consistently truncating the theory to a theory of pure (super-)gravity with the gravitational sector containing only Einstein-Hilbert, cosmological constant and Chern-Simons terms. We also outline the procedure for finding the parameters of the truncated theory. As an example we consider dimensional reduction on S^2 of the 5-dimensional minimal supergravity with curvature squared terms and obtain the truncated theory without any curvature squared terms. This truncated theory reproduces correctly the exact central charge of the boundary CFT.Comment: LaTeX file, 22 page

    Impact of annealing on CuInSe2 thin films and its Schottky interface

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    The room temperature current–voltage (I-V) characteristics of the Al/p-CuInSe2 Schottky Diodes fabricated on thermally evaporated CIS thin films, before and after annealing, were studied. Prior to their diode formation, the undertaken CIS thin films were compared on the basis of structural, morphological and electrical investigations. Wherein, annealed films showed an increase in the grain size and carrier concentration values while decrease in resistivity. I-V analysis of the Schottky diodes depicted decrease in the barrier heights and increase in ideality factors of those formed on annealed films. The diodes, thus, indicated the existence of barrier inhomogenity at the M-S interface. The annealed Schottky diodes also demonstrated better ideality factor values with increased thickness of CIS layer. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2792

    Structural and electrical properties of c-axis oriented Y1-xCaxBa2(Cu1-yZny)3O7-delta thin films grown by pulsed laser deposition

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    Ca- and Zn-subsituted Y1-xCaxBa2(Cu1-yZny)O7-delta (x = 0, 0.05 and y = 0, 0.02, 0.04, 0.05) thin films were grown on SrTiO3 (100) substrates using the pulsed laser deposition (PLD) technique. Effects of various growth parameters on the quality of the film were studied via X-ray diffraction (XRD), atomic force microscopy (AFM), and in-plane resistivity, rhoab(T), measurements. The deposition temperature and oxygen partial pressure were gradually increased to 820C and 1.20 mbar respectively. Films grown under these conditions exhibited good c-axis orientation (primarily limited by the grain size) and low values of the extrapolated residual resistivity, rho(0), at zero temperature. The planar hole content, p, was determined from the room temperature thermopower, S[290K], measurements and the effects of oxygen annealing were also studied. Fully oxygenated samples were found to be overdoped with p ~ 0.195. The Superconducting transition temperature Tc(p), and rho(T,p) showed the expected systematic variations with changing Zn content.Comment: Submitted to Physica C (2003

    Clapping modes in unconventional superconductors

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    We consider a superconducting state with a mixed symmetry order parameter components, e.g. d+isd+is or d+idd+id' with d=dxyd'= d_{xy}. We argue for the existence of the new orbital magnetization mode which corresponds to the oscillations of relative phase ϕ\phi between two components around an equilibrium value of ϕ=π2\phi = \frac{\pi}{2}. It is similar to the so called ``clapping'' mode in superfluid 3HeA^3He-A. We estimate the frequency of this mode ω0(B,T)\omega_0(B,T) depending on the field and temperature for the specific case of magnetic field induced dd' state. We find that this mode is {\em tunable} with an applied magnetic field with \omega_0(B,T) \propto B \0, where \0 is the magnitude of the d-wave order parameter. We argue also that similar filed induced clapping mode should be present in an organic p-wave superconductors.Comment: M2S-HTSC-VI Proceedings, Feb 2000, Houston, TX, USA; 4 pages. Physica C, to be publishe

    The 198Au beta-half-life in the metal Au revisited

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    The half-life of the beta-decay of 198Au has been measured for room temperature and 12 K. The resulting values of T(RT) = 2.684 +- 0.004 d and T(12 K) = 2.687 +- 0.005 d agree well within statistical uncertainties. An evidence for a temperature dependence of the half-life was not observed.Comment: accepted for publication in Eur. Phys. J.

    A Multi-centre Study to Evaluate the Long-Term Efficacy and Safety of Biosimilar Infliximab (Infimab™) in Ankylosing Spondylitis in Real-world Clinical Settings - A perspective from Eastern India

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    Introduction: Owing to dearth of data on infliximab biosimilars in Indian patients, a pan-India case database-based study with infliximab biosimilar BOW015 (Infimab™) was carried out to capture its efficacy and safety in real world clinical settings in India. Here, we assessed its efficacy and safety in ankylosing spondylitis (AS) among patients in the East India cohort. Materials and methods: Data were collected from multiple centers across the eastern region of India. Patients diagnosed with AS, within the preceding 4-6 months during the preceding one year were included in the study. Patients who were given BOW015 for other indications, prior innovator infliximab or other biologics were excluded from the study. Primary variable was Ankylosing Spondylitis Disease Activity Scale (ASDAS) response defined as change of &gt; 2 in the ASDAS score from the baseline by 4-6 months of follow up. Results: The cohort consisted of 149 patients, predominantly male (69.8%), with mean (±SD) age of 36.75 (±11.11) years and mean (±SD) body weight of 58.26 (±15.4) kgs. Of the treated patients, 91 (61.1%) patients were administered four doses, 10 (6.7%) patients were administered three doses, 37 (24.8%) patients were administered two doses and 11 (7.4%) patients were administered only a single dose of BOW015. In the final analysis set, 81 patients had data at baseline and 4th visit. Among the 81 patients, 74 (91%) patients achieved major improvement, 5 (6%) patients achieved clinically important improvement and 2 (3%) were non-responders at 4th visit. Secondarily, cross categorization of the cohort into disease activity categories by number of infusions administered from baseline to 4th visit and assessment of trends in Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores were also carried out and these too confirmed the efficacy of BOW015. Conclusion: Infimab™ (BOW015) showed significant improvement in ASDAS and BASDAI in patients with AS at the end of 4-6 months of follow up with its clinical benefits being apparent as early as first dose of BOW015

    Event-B Patterns for Specifying Fault-Tolerance in Multi-Agent Interaction

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    Interaction in a multi-agent system is susceptible to failure. A rigorous development of a multi-agent system must include the treatment of fault-tolerance of agent interactions for the agents to be able to continue to function independently. Patterns can be used to capture fault-tolerance techniques. A set of modelling patterns is presented that specify fault-tolerance in Event-B specifications of multi-agent interactions. The purpose of these patterns is to capture common modelling structures for distributed agent interaction in a form that is re-usable on other related developments. The patterns have been applied to a case study of the contract net interaction protocol
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