Superoptimal Preconditioned Conjugate Gradient Iteration for Image Deblurring

We study the superoptimal Frobenius operators in the two-level circulant algebra. We consider two specific viewpoints: ( 1) the regularizing properties in imaging and ( 2) the computational effort in connection with the preconditioned conjugate gradient method. Some numerical experiments illustrating the effectiveness of the proposed technique are given and discussed

Promotion of proliferation and metastasis of hepatocellular carcinoma by LncRNA00673 based on the targeted-regulation of notch signaling pathway

we read with great interest the paper by Dr. Chen et al1, recently published in European Review for Medical and Pharmacological Sciences and titled ‘‘Promotion of proliferation and metastasis of hepatocellular carcinoma by LncRNA00673 based on the targeted-regulation of notch signaling pathway’’. Authors concluded that lncRNA00673 is highly expressed and may be a potential target for the treatment of Hepatocellular Carcinoma (HCC). Moreover, according to authors, it can promote the proliferation and metastasis of HCC by the regulation of Notch signaling pathway. We congratulate the authors for their interesting work

Free boundary problems for Tumor Growth: a Viscosity solutions approach

The mathematical modeling of tumor growth leads to singular stiff pressure law limits for porous medium equations with a source term. Such asymptotic problems give rise to free boundaries, which, in the absence of active motion, are generalized Hele-Shaw flows. In this note we use viscosity solutions methods to study limits for porous medium-type equations with active motion. We prove the uniform convergence of the density under fairly general assumptions on the initial data, thus improving existing results. We also obtain some additional information/regularity about the propagating interfaces, which, in view of the discontinuities, can nucleate and, thus, change topological type. The main tool is the construction of local, smooth, radial solutions which serve as barriers for the existence and uniqueness results as well as to quantify the speed of propagation of the free boundary propagation

Determinants of influenza vaccination among solid organ transplant recipients attending Sicilian reference center

Among solid organ transplant recipients, influenza infection is commonly associated with higher morbidity and mortality than immunocompetent hosts. Therefore, in these subjects influenza vaccination is of paramount importance. The main objective of the study was to assess compliance to vaccination and analyze factors associated with influenza vaccination of solid organ transplant recipients admitted to the Sicilian solid organ transplant Reference Center IRCCS-ISMETT in Palermo during 2014\u20132015 influenza season. Thirty one (37.8%) out of 82 solid organ transplant recipients were vaccinated against influenza. The main reason for vaccination refusal was fear of adverse reaction (n = 16, 31.4%), impaired health status (n = 14, 27.4%) and low vaccine efficacy (n = 10, 19.6%). Vaccinated solid organ transplant recipients compare with unvaccinated had smaller hospital admissions for infectious respiratory diseases (9.7% Vs 23.5%) during surveillance period. On multivariate analysis the factors positively associated with influenza vaccination were the advice of Reference Center physicians (OR 53.4, p < 0.001) and to perform vaccine against pneumococcus (OR 7.0, p = 0.016). This study showed that Reference Center physicians play a key role on vaccine communication and recommendation for patients at risk and it underlines the effectiveness of influenza vaccination in solid organ transplant recipients. However, it remains that, although physician advice resulted a strong determinant for vaccination, influenza vaccination coverage in this subset of population remains still unsatisfactory

Improving Interferometric Null Depth Measurements using Statistical Distributions: Theory and First Results with the Palomar Fiber Nuller

A new "self-calibrated" statistical analysis method has been developed for the reduction of nulling interferometry data. The idea is to use the statistical distributions of the fluctuating null depth and beam intensities to retrieve the astrophysical null depth (or equivalently the object's visibility) in the presence of fast atmospheric fluctuations. The approach yields an accuracy much better (about an order of magnitude) than is presently possible with standard data reduction methods, because the astrophysical null depth accuracy is no longer limited by the magnitude of the instrumental phase and intensity errors but by uncertainties on their probability distributions. This approach was tested on the sky with the two-aperture fiber nulling instrument mounted on the Palomar Hale telescope. Using our new data analysis approach alone-and no observations of calibrators-we find that error bars on the astrophysical null depth as low as a few 10-4 can be obtained in the near-infrared, which means that null depths lower than 10-3 can be reliably measured. This statistical analysis is not specific to our instrument and may be applicable to other interferometers

A remark on an overdetermined problem in Riemannian Geometry

Let $(M,g)$ be a Riemannian manifold with a distinguished point $O$ and assume that the geodesic distance $d$ from $O$ is an isoparametric function. Let $\Omega\subset M$ be a bounded domain, with $O \in \Omega$, and consider the problem $\Delta_p u = -1$ in $\Omega$ with $u=0$ on $\partial \Omega$, where $\Delta_p$ is the $p$-Laplacian of $g$. We prove that if the normal derivative $\partial_{\nu}u$ of $u$ along the boundary of $\Omega$ is a function of $d$ satisfying suitable conditions, then $\Omega$ must be a geodesic ball. In particular, our result applies to open balls of $\mathbb{R}^n$ equipped with a rotationally symmetric metric of the form $g=dt^2+\rho^2(t)\,g_S$, where $g_S$ is the standard metric of the sphere.Comment: 8 pages. This paper has been written for possible publication in a special volume dedicated to the conference "Geometric Properties for Parabolic and Elliptic PDE's. 4th Italian-Japanese Workshop", organized in Palinuro in May 201

Bodybuilders' accounts of synthol use: The construction of lay expertise online.

Synthol is an injectable oil used by bodybuilders to make muscles appear bigger. Widely available on the Internet, it is reported to carry a wide range of health risks and side effects such as localised skin problems, nerve damage and oil-filled cysts, as well as muscle damage and the development of scar tissue. Given the tension between health risk and quick muscle enlargement, how lay users explain and justify their synthol intake becomes an important question. Drawing on discourse analysis, we focus on how lay expertise is worked up by users in the absence of available specialist knowledge by invoking medical and pharmaceutical discourses as legitimation, providing novices with support, gaining trust through positive personal narratives and thus gaining credibility as experts. Results have clear implications for health promotion interventions with bodybuilders

Fundamental Parameters and Chemical Composition of Arcturus

We derive a self-consistent set of atmospheric parameters and abundances of 17 elements for the red giant star Arcturus: Teff = 4286+/-30 K, logg = 1.66+/-0.05, and [Fe/H] = -0.52+/-0.04. The effective temperature was determined using model atmosphere fits to the observed spectral energy distribution from the blue to the mid-infrared (0.44 to 10 um). The surface gravity was calculated using the trigonometric parallax of the star and stellar evolution models. A differential abundance analysis relative to the solar spectrum allowed us to derive iron abundances from equivalent width measurements of 37 FeI and 9 FeII lines, unblended in the spectra of both Arcturus and the Sun; the [Fe/H] value adopted is derived from FeI lines. We also determine the mass, radius, and age of Arcturus: M = 1.08+/-0.06 Msun, R = 25.4+/-0.2 Rsun, and t = 7.1(+1.5/-1.2) Gyr. Finally, abundances of the following elements are measured from an equivalent width analysis of atomic features: C, O, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, and Zn. We find the chemical composition of Arcturus typical of that of a local thick-disk star, consistent with its kinematics.Comment: ApJ, in pres

A Study of the B-V Colour Temperature Relation

We attempt to construct a B-V colour temperature relation for stars in the least model dependent way employing the best modern data. The fit we obtained with the form Teff = Teff((B-V)0,[Fe/H],log g) is well constrained and a number of tests show the consistency of the procedures for the fit. Our relation covers from F0 to K5 stars with metallicity [Fe/H] = -1.5 to +0.3 for both dwarfs and giants. The residual of the fit is 66 K, which is consistent with what are expected from the quality of the present data. Metallicity and surface gravity effects are well separated from the colour dependence. Dwarfs and giants match well in a single family of fit, differing only in log g. The fit also detects the Galactic extinction correction for nearby stars with the amount E(B-V) = 0.26 +/-0.03 mag/kpc. Taking the newly obtained relation as a reference we examine a number of B-V colour temperature relations and atmosphere models available in the literature. We show the presence of a systematic error in the colour temperature relation from synthetic calculations of model atmospheres; the systematic error across K0 to K5 dwarfs is 0.04-0.05 mag in B-V, which means 0.25-0.3 mag in Mv for the K star range. We also argue for the error in the temperature scale used in currently popular stellar population synthesis models; synthetic colours from these models are somewhat too blue for aged elliptical galaxies. We derive the colour index of the sun (B-V)sun = 0.627 +/-0.018, and discuss that redder colours (e.g., 0.66-0.67) often quoted in the literature are incompatible with the colour-temperature relation.Comment: AASLaTeX (aaspp4.sty),36 pages (13 figures included), submitted to Astronomical Journal, replaced (typo in author name