3,051 research outputs found

    The effect of the linear term on the wavelet estimator of primordial non-Gaussianity

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    In this work we present constraints on different shapes of primordial non-Gaussianity using the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year data and the spherical Mexican hat wavelet fnl estimator including the linear term correction. In particular we focus on the local, equilateral and orthogonal shapes. We first analyse the main statistical properties of the wavelet estimator and show the conditions to reach optimality. We include the linear term correction in our estimators and compare the estimates with the values already published using only the cubic term. The estimators are tested with realistic WMAP simulations with anisotropic noise and the WMAP KQ75 sky cut. The inclusion of the linear term correction shows a negligible improvement (< 1 per cent) in the error-bar for any of the shapes considered. The results of this analysis show that, in the particular case of the wavelet estimator, the optimality for WMAP anisotropy levels is basically achieved with the mean subtraction and in practical terms there is no need of including a linear term once the mean has been subtracted. Our best estimates are now: local fnl = 39.0 +/ 21.4, equilateral fnl = -62.8 +/- 154.0 and orthogonal fnl = -159.8 +/- 115.1 (all cases 68 per cent CL). We have also computed the expected linear term correction for simulated Planck maps with anisotropic noise at 143 GHz following the Planck Sky Model and including a mask. The improvement achieved in this case for the local fnl error-bar is also negligible (0.4 per cent).Comment: 8 pages, 5 figures, 4 tables. Minor revision, one figure added, accepted for publication in MNRA

    Truncated K-moment problems in several variables

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    Let ββ(2n)\beta\equiv\beta^{(2n)} be an N-dimensional real multi-sequence of degree 2n, with associated moment matrix M(n)M(n)(β)\mathcal{M}(n)\equiv \mathcal{M}(n)(\beta), and let r:=rankM(n)r:=rank \mathcal{M}(n). We prove that if M(n)\mathcal{M}(n) is positive semidefinite and admits a rank-preserving moment matrix extension M(n+1)\mathcal{M}(n+1), then M(n+1)\mathcal{M}(n+1) has a unique representing measure \mu, which is r-atomic, with supp \muequalto equal to \mathcal{V}(\mathcal{M}(n+1)),thealgebraicvarietyof, the algebraic variety of \mathcal{M}(n+1).Further,βhasanratomic(minimal)representingmeasuresupportedinasemialgebraicset. Further, \beta has an r-atomic (minimal) representing measure supported in a semi-algebraic set K_{\mathcal{Q}}subordinatetoafamily subordinate to a family \mathcal{Q}% \equiv\{q_{i}\}_{i=1}^{m}\subseteq\mathbb{R}[t_{1},...,t_{N}]ifandonlyif if and only if \mathcal{M}(n)ispositivesemidefiniteandadmitsarankpreservingextension is positive semidefinite and admits a rank-preserving extension \mathcal{M}(n+1)forwhichtheassociatedlocalizingmatrices for which the associated localizing matrices \mathcal{M}_{q_{i}}(n+[\frac{1+\deg q_{i}}{2}])arepositivesemidefinite are positive semidefinite (1\leq i\leq m);inthiscase,μ(asabove)satisfiessuppμKQ; in this case, \mu (as above) satisfies supp \mu\subseteq K_{\mathcal{Q}}, and \mu has precisely rank \mathcal{M}(n)-rank \mathcal{M}_{q_{i}}(n+[\frac{1+\deg q_{i}}{2}])atomsin atoms in \mathcal{Z}(q_{i})\equiv {t\in\mathbb{R}^{N}:q_{i}(t)=0},, 1\leq i\leq m$.Comment: 33 pages; to appear in J. Operator Theor

    Effectiveness of entomopathogenic nematodes in the control of Cydia pomonella larvae in Northern Italy

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    Since 2006, a large scale research on the effectiveness of entomopathogenic nematodes (EPN) in the control of codling moth (CM), Cydia pomonella, overwintering larvae has been performed on about 35 ha of pear orchards per year in Emilia-Romagna, Northern Italy. Steinernema carpocapsae and Steinernema feltiae activity was checked after spray applications of EPNs to the trunk and branches. In 2006, the treatment was applied either in spring or in autumn at different doses, before CM pupation; in 2007 the EPN treatment was applied only in autumn at 1.5 x 109 I.J. ha –1. Every year it was distributed by means of a conventional mist blower. The larval mortality was assessed directly on sentinel larvae in card boards on the trunks and indirectly on the eggs laid by the females of the first CM generation in spring. Moreover, each year, a trial was performed applying only S. carpocapsae on sentinel larvae with the aim of testing this nematode at suitable temperatures but at different water volumes. The CM sentinel larvae were effectively parasitized after autumnal EPN application. Moreover, the egg assessment demonstrated a good decrease in CM population in spring 2007, when EPNs had been applied at the best weather conditions (t° 12-14 °C and rain) in the previous autumn

    Nanofacies de los sedimentos terciarios de las béticas

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    Diferenciamos en los sedimentos marinos del Oligoceno superior- Mioceno superior de las Béticas ("moronitas")i nco nanofacies: de diatomeas aciculares, biogénica, cocolítico-detrítica, espicularcocolítico- detritica y detritica. Establecemos las relaciones existentes entre ellas discutiendo su origen y formación

    Factors associated with costs of hospitalization of severely mentally Ill patients

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    Background: Efforts to contain costs associated with general medical care include particular efforts for psychiatric disorders. Hospitalization represents the largest component of costs for psychiatric care and there is growing interest in balancing clinical needs against limiting costs of inpatient psychiatric care of patients with severe mental illnesses. This study aimed to evaluate clinical factors associated with actual costs of inpatient psychiatric care. Method: We evaluated a cohort of 589 hospitalized psychiatric patients with severe mental illnesses at a nonprofit, university-affiliated psychiatric hospital for factors associated with annualized total costs of inpatient care over a three-year period, using bivariate and multivariate analyses. Results: As expected, days-hospitalized was the major determinant of total costs of hospital care. In addition, several clinical and treatment factors also were associated significantly and independently with costs in multivariate modeling. These included presence of psychosis, electroconvulsive treatment, specialist consultations, use of multiple antipsychotics or of clozapine, and being discharged to a supervised living arrangement, but not sex, age, marital status, employment, or substance abuse. Discussion: As expected, costs of psychiatric hospitalization were dominated by per-diem charges, but also influenced by other, potentially modifiable treatment factors generally associated with more severe psychotic illnesses. The study is based on actual costs rather than on insurer-reimbursements and a large study-sample, though at a single institution. Specific factors identified encourage focusing on patient characteristics associated with greater costs and redoubled efforts to apply and improve alternative, cost-effective interventions such as partialhospital and intensive outpatient treatment

    Real-world evidence in economic evaluations: really realistic?

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    Wilkinson Microwave Anisotropy Probe 7-yr constraints on fNL with a fast wavelet estimator

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    A new method to constrain the local non-linear coupling parameter fNL based on a fast wavelet decomposition is presented. Using a multiresolution wavelet adapted to the HEALPix pixelization, we have developed a method that is 10^2 times faster than previous estimators based on isotropic wavelets and 10^3 faster than the KSW bispectrum estimator, at the resolution of the Wilkinson Microwave Anisotropy Probe (WMAP) data. The method has been applied to the WMAP 7-yr V+W combined map, imposing constraints on fNL of -69 < fNL < 65 at the 95 per cent CL. This result has been obtained after correcting for the contribution of the residual point sources which has been estimated to be fNL = 7 +/- 6. In addition, a Gaussianity analysis of the data has been carried out using the third order moments of the wavelet coefficients, finding consistency with Gaussianity. Although the constrainsts imposed on fNL are less stringent than those found with optimal estimators, we believe that a very fast method, as the one proposed in this work, can be very useful, especially bearing in mind the large amount of data that will be provided by future experiments, such as the Planck satellite. Moreover, the localisation of wavelets allows one to carry out analyses on different regions of the sky. As an application, we have separately analysed the two hemispheres defined by the dipolar modulation proposed by Hoftuft et al. (2009). We do not find any significant asymmetry regarding the estimated value of fNL in those hemispheres.Comment: 8 pages, 5 figures. Submitted and Accepted for publication in MNRA
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