1,651 research outputs found

    Taming the ϵ\epsilon-expansion with Large Spin Perturbation Theory

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    We apply analytic bootstrap techniques to the four-point correlator of fundamental fields in the Wilson-Fisher model. In an ϵ\epsilon-expansion crossing symmetry fixes the double discontinuity of the correlator in terms of CFT data at lower orders. Large spin perturbation theory, or equivalently the recently proposed Froissart-Gribov inversion integral, then allows one to reconstruct the CFT data of intermediate operators of any spin. We use this method to compute the anomalous dimensions and OPE coefficients of leading twist operators. To cubic order in ϵ\epsilon the double discontinuity arises solely from the identity operator and the scalar bilinear operator, making the computation straightforward. At higher orders the double discontinuity receives contributions from infinite towers of higher spin operators. At fourth order, the structure of perturbation theory leads to a proposal in terms of functions of certain degree of transcendentality, which can then be fixed by symmetries. This leads to the full determination of the CFT data for leading twist operators to fourth order.Comment: 16 pages. v2: Added discussion on low spin spectru

    Increasing the Reliability of Adaptive Quadrature Using Explicit Interpolants

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    We present two new adaptive quadrature routines. Both routines differ from previously published algorithms in many aspects, most significantly in how they represent the integrand, how they treat non-numerical values of the integrand, how they deal with improper divergent integrals and how they estimate the integration error. The main focus of these improvements is to increase the reliability of the algorithms without significantly impacting their efficiency. Both algorithms are implemented in Matlab and tested using both the "families" suggested by Lyness and Kaganove and the battery test used by Gander and Gautschi and Kahaner. They are shown to be more reliable, albeit in some cases less efficient, than other commonly-used adaptive integrators.Comment: 32 pages, submitted to ACM Transactions on Mathematical Softwar

    An alternative to diagrams for the critical O(N) model: dimensions and structure constants to order 1/N21/N^2

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    We apply the methods of modern analytic bootstrap to the critical O(N)O(N) model in a 1/N1/N expansion. At infinite NN the model possesses higher spin symmetry which is weakly broken as we turn on 1/N1/N. By studying consistency conditions for the correlator of four fundamental fields we derive the CFT-data for all the (broken) currents to order 1/N1/N, and the CFT-data for the non-singlet currents to order 1/N21/N^2. To order 1/N1/N our results are in perfect agreement with those in the literature. To order 1/N21/N^2 we reproduce known results for anomalous dimensions and obtain a variety of new results for structure constants, including the global symmetry central charge CJC_J to this order.Comment: 32 pages + appendices, 2 figures. v2: Improved presentation + new appendix considering mixed correlator. Version to appear in JHE

    Who Is In Charge, and Who Should Be? The Disciplinary Role of the Commander in Military Justice Systems

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    BackgroundStandard therapy for newly diagnosed glioblastoma is radiotherapy plus temozolomide. In this phase 3 study, we evaluated the effect of the addition of bevacizumab to radiotherapy-temozolomide for the treatment of newly diagnosed glioblastoma. MethodsWe randomly assigned patients with supratentorial glioblastoma to receive intravenous bevacizumab (10 mg per kilogram of body weight every 2 weeks) or placebo, plus radiotherapy (2 Gy 5 days a week; maximum, 60 Gy) and oral temozolomide (75 mg per square meter of body-surface area per day) for 6 weeks. After a 28-day treatment break, maintenance bevacizumab (10 mg per kilogram intravenously every 2 weeks) or placebo, plus temozolomide (150 to 200 mg per square meter per day for 5 days), was continued for six 4-week cycles, followed by bevacizumab monotherapy (15 mg per kilogram intravenously every 3 weeks) or placebo until the disease progressed or unacceptable toxic effects developed. The coprimary end points were investigator-assessed progression-free survival and overall survival. ResultsA total of 458 patients were assigned to the bevacizumab group, and 463 patients to the placebo group. The median progression-free survival was longer in the bevacizumab group than in the placebo group (10.6 months vs. 6.2 months; stratified hazard ratio for progression or death, 0.64; 95% confidence interval [CI], 0.55 to 0.74; P<0.001). The benefit with respect to progression-free survival was observed across subgroups. Overall survival did not differ significantly between groups (stratified hazard ratio for death, 0.88; 95% CI, 0.76 to 1.02; P=0.10). The respective overall survival rates with bevacizumab and placebo were 72.4% and 66.3% at 1 year (P=0.049) and 33.9% and 30.1% at 2 years (P=0.24). Baseline health-related quality of life and performance status were maintained longer in the bevacizumab group, and the glucocorticoid requirement was lower. More patients in the bevacizumab group than in the placebo group had grade 3 or higher adverse events (66.8% vs. 51.3%) and grade 3 or higher adverse events often associated with bevacizumab (32.5% vs. 15.8%). ConclusionsThe addition of bevacizumab to radiotherapy-temozolomide did not improve survival in patients with glioblastoma. Improved progression-free survival and maintenance of baseline quality of life and performance status were observed with bevacizumab; however, the rate of adverse events was higher with bevacizumab than with placebo.

    Efficient red electroluminescence from diketopyrrolopyrrole copolymerised with a polyfluorene

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    We thank the EC Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. 212311 (ONE-P), the RTN THREADMILL (EU-Contract No.: MRTN-CT-2006-036040), the ITNs SUPERIOR (PITN-CT-2009-238177), and CONTEST (PITN-CT-2012-317488) as well as the Royal Society, and EPSRC for funding

    Cosmic shear requirements on the wavelength-dependence of telescope point spread functions

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    Cosmic shear requires high precision measurement of galaxy shapes in the presence of the observational Point Spread Function (PSF) that smears out the image. The PSF must therefore be known for each galaxy to a high accuracy. However, for several reasons, the PSF is usually wavelength dependent, therefore the differences between the spectral energy distribution of the observed objects introduces further complexity. In this paper we investigate the effect of the wavelength-dependence of the PSF, focusing on instruments in which the PSF size is dominated by the diffraction-limit of the telescope and which use broad-band filters for shape measurement. We first calculate biases on cosmological parameter estimation from cosmic shear when the stellar PSF is used uncorrected. Using realistic galaxy and star spectral energy distributions and populations and a simple three-component circular PSF we find that the colour-dependence must be taken into account for the next generation of telescopes. We then consider two different methods for removing the effect (i) the use of stars of the same colour as the galaxies and (ii) estimation of the galaxy spectral energy distribution using multiple colours and using a telescope model for the PSF. We find that both of these methods correct the effect to levels below the tolerances required for per-cent level measurements of dark energy parameters. Comparison of the two methods favours the template-fitting method because its efficiency is less dependent on galaxy redshift than the broad-band colour method and takes full advantage of deeper photometry.Comment: 10 pages, 8 figures, version accepted for publication in MNRA

    Classical novae from the POINT-AGAPE microlensing survey of M31 -- I. The nova catalogue

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    The POINT-AGAPE survey is an optical search for gravitational microlensing events towards the Andromeda Galaxy (M31). As well as microlensing, the survey is sensitive to many different classes of variable stars and transients. Here we describe the automated detection and selection pipeline used to identify M31 classical novae (CNe) and we present the resulting catalogue of 20 CN candidates observed over three seasons. CNe are observed both in the bulge region as well as over a wide area of the M31 disk. Nine of the CNe are caught during the final rise phase and all are well sampled in at least two colours. The excellent light-curve coverage has allowed us to detect and classify CNe over a wide range of speed class, from very fast to very slow. Among the light-curves is a moderately fast CN exhibiting entry into a deep transition minimum, followed by its final decline. We have also observed in detail a very slow CN which faded by only 0.01 mag day1^{-1} over a 150 day period. We detect other interesting variable objects, including one of the longest period and most luminous Mira variables. The CN catalogue constitutes a uniquely well-sampled and objectively-selected data set with which to study the statistical properties of classical novae in M31, such as the global nova rate, the reliability of novae as standard-candle distance indicators and the dependence of the nova population on stellar environment. The findings of this statistical study will be reported in a follow-up paper.Comment: 21 pages, 13 figures, re-submitted for publication in MNRAS, typos corrected, references updated, figures 5-9 made cleare

    Proinsulin C-peptide elicits disaggregation of insulin resulting in enhanced physiological insulin effects

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    Using surface plasmon resonance (SPR) and electrospray mass spectrometry (ESI-MS), proinsulin C-peptide was found to influence insulin-insulin interactions. In SPR with chip-bound insulin, C-peptide mixed with analyte insulin increased the binding, while alone C-peptide did not. A control peptide with the same residues in random sequence had little effect. In ESI-MS, C-peptide lowered the presence of insulin hexamer. The data suggest that C-peptide promotes insulin disaggregation. Insulin/insulin oligomer μM dissociation constants were determined. Compatible with these findings, type 1 diabetic patients receiving insulin and C-peptide developed 66% more stimulation of glucose metabolism than when given insulin alone. A role of C-peptide in promoting insulin disaggregation may be important physiologically during exocytosis of pancreatic β-cell secretory granulae and pharmacologically at insulin injection sites. It is compatible with the normal co-release of C-peptide and insulin and may contribute to the beneficial effect of C-peptide and insulin replacement in type 1 diabetics

    Diabetes: cost of illness in Norway

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    <p>Abstract</p> <p>Background</p> <p>Diabetes mellitus places a considerable burden on patients in terms of morbidity and mortality and on society in terms of costs. Costs related to diabetes are expected to increase due to increasing prevalence of type 2 diabetes. The aim of this study was to estimate the health care costs attributable to type 1 and type 2 diabetes in Norway in 2005.</p> <p>Methods</p> <p>Data on inpatient hospital services, outpatient clinic visits, physician services, drugs, medical equipment, nutrition guidance, physiotherapy, acupuncture, foot therapy and indirect costs were collected from national registers and responses to a survey of 584 patients with diabetes. The study was performed with a prevalence approach. Uncertainty was explored by means of bootstrapping.</p> <p>Results</p> <p>When hospital stays with diabetes as a secondary diagnosis were excluded, the total costs were €293 million, which represents about 1.4% of the total health care expenditure. Pharmaceuticals accounted for €95 million (32%), disability pensions €48 million (16%), medical devices €40 million (14%) and hospital admissions €21 million (7%). Patient expenditures for acupuncture, physiotherapy and foot therapy were many times higher than expenditure for nutritional guidance. Indirect costs (lost production from job absenteeism) accounted for €70.1 million (24% of the €293 million) and included sick leave (€16.7 million), disability support and disability pensions (€48.2 million) and other indirect costs (€5.3 million). If all diabetes related hospital stays are included (primary- and secondary diagnosis) total costs amounts to €535 million, about 2.6% of the total health care expenditure in Norway.</p> <p>Conclusions</p> <p>Diabetes represents a considerable burden to society in terms of health care costs and productivity losses.</p
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