Kohn-Sham calculations combined with an average pair-density functional theory

A recently developed formalism in which Kohn-Sham calculations are combined with an ``average pair density functional theory'' is reviewed, and some new properties of the effective electron-electron interaction entering in this formalism are derived. A preliminary construction of a fully self-consitent scheme is also presented in this framework.Comment: submitted to Int. J. Mod. Phys. B (proceedings of the 30th International Workshop on Condensed Matter Theories

An automated system for lung nodule detection in low-dose computed tomography

A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector helical Computed Tomography (CT) images was developed in the framework of the MAGIC-5 Italian project. One of the main goals of this project is to build a distributed database of lung CT scans in order to enable automated image analysis through a data and cpu GRID infrastructure. The basic modules of our lung-CAD system, a dot-enhancement filter for nodule candidate selection and a neural classifier for false-positive finding reduction, are described. The system was designed and tested for both internal and sub-pleural nodules. The results obtained on the collected database of low-dose thin-slice CT scans are shown in terms of free response receiver operating characteristic (FROC) curves and discussed.Comment: 9 pages, 9 figures; Proceedings of the SPIE Medical Imaging Conference, 17-22 February 2007, San Diego, California, USA, Vol. 6514, 65143

Development of a new screening tool for cyber pornography. Psychometric properties of the Cyber Pornography Addiction Test (CYPAT)

Objective: Internet pornography addiction typically involves viewing, downloading and trading online pornography or engagement in adult fantasy role-play. There are some well-validated inventories measuring perceived addiction to internet pornography but these instruments are often too long for a functionally use and fast scoring. The aim of this study was to evaluate the psychometric properties of the cyber pornography addiction test (CYPAT), a new, brief, screening measure for assessing cyber pornography.Method: Participants of this study completed the CYPAT, the CPUI, the TAS-20 and the FACES-IV. Descriptive statistics were calculated and Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were applied.Results: Cronbach's alpha coefficient suggested excellent reliability of the measure. Results of this study revealed also good construct, convergent and divergent validity.Conclusions: CYPAT is a brief self-report screening scale composed of 11 items scored on a five-point Likert scale with good psychometrics properties. The implications of these findings for future theoretical and empirical research in this field are discusse

Computer-aided detection of pulmonary nodules in low-dose CT

A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector helical CT images with 1.25 mm slice thickness is being developed in the framework of the INFN-supported MAGIC-5 Italian project. The basic modules of our lung-CAD system, a dot enhancement filter for nodule candidate selection and a voxel-based neural classifier for false-positive finding reduction, are described. Preliminary results obtained on the so-far collected database of lung CT scans are discussed.Comment: 3 pages, 4 figures; Proceedings of the CompIMAGE - International Symposium on Computational Modelling of Objects Represented in Images: Fundamentals, Methods and Applications, 20-21 Oct. 2006, Coimbra, Portuga

Two new differential equations of turbulent dissipation rate and apparent viscosity for non-Newtonian fluids.

A new equation for the dissipation rate of turbulent kinetic energy is derived exactly in conservative form for a Generalized Newtonian Fluid (GNF). The transport equations for mass, momentum, and turbulent kinetic energy are written along to the transport equation for the shear rate. A new transport equation for the apparent viscosity is derived assuming the viscosity as dependent only on the shear rate. The assumption is of incompressible two-dimensional GNF flow

Three-Dimensional Numerical Simulation of Blood Flow in Two Coronary Stents.

The aim of the present study is to carry out Computational Fluid Dynamics simulations in a realistic three dimensional geometry of two stent under physiological conditions. The two stent, similar to real coronary ones, are both made of 12 rings but are differing as far as the position of the struts is concerned. One type has parallel-connectors and the other transverse-ones. The artery is modeled as rigid cylinder and the fluid is assumed as incompressible Newtonian fluid in laminar flow with the average physical properties of blood. The commercial computational fluid dynamic code FLUENT is used with the mesh made of non-uniform tetrahedrons. The mesh independence is proved using the steady state results of the wall shear stress. The parameters correlated to neo-intimal hyperplasia, such as wall shear stress, magnitude of wall shear stress gradient, and oscillatory shear index, are investigated. Time variation of the parameters is investigated with the conclusion that the stent with parallel-connectors has a better fluid dynamic behavior

First-principles calculations and bias-dependent STM measurements at the alpha-Sn/Ge(111) surface: a clear indication for the 1U2D configuration

The nature of the alpha-Sn/Ge(111) surface is still a matter of debate. In particular, two possible configurations have been proposed for the 3x3 ground state of this surface: one with two Sn adatoms in a lower position with respect to the third one (1U2D) and the other with opposite configuration (2U1D). By means of first-principles quasiparticle calculations we could simulate STM images as a function of bias voltage and compare them with STM experimental results at 78K, obtaining an unambiguous indication that the stable configuration for the alpha-Sn/Ge(111) surface is the 1U2D. The possible inequivalence of the two down Sn adatoms is also discussed.Comment: Submitted to PR