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Many local integral methods are based on an integral formulation over small and heavily overlapping stencils with local Radial Basis Functions (RBFs) interpolations. These functions have become an extremely effective tool for interpolation on scattered node sets, however the ill-conditioning of the interpolation matrix – when the RBF shape parameter tends to zero corresponding to best accuracy – is a major drawback. Several stabilizing methods have been developed to deal with this near flat RBFs in global approaches but there are not many applications to local integral methods. In this paper we present a new method called Stabilized Local Boundary Domain Integral Method (LBDIM-St) with a stable calculation of the local RBF approximation for small shape parameter that stabilizes the numerical error. We present accuracy results for some Partial Differential Equations (PDEs) such as Poisson, convection–diffusion, thermal boundary layer and an elliptic equation with variable coefficients. [ABSTRACT FROM AUTHOR]

El uso de biomarcadores en la detección del cáncer de próstata (CP) puede disminuir el sobrediagnóstico y sobretratamiento de CP no significativos. Analizamos la utilidad y aplicabilidad del marcador SelectMDx® en un entorno de práctica clínica habitual.

Most implementations of meshless BEMs use a circular integration contours (spherical in 3D) embedded into a local interpolation stencil with the so-called Companion Solution (CS) as a kernel, in order to eliminate the contribution of the single layer potential. However, the Dirichlet Green's Function (DGF) is the unique Fundamental Solution that is identically zero at any given close surface and therefore eliminates the single layer potential. One of the main objectives of this work is to show that the CS is nothing else than the DGF for a circle collocated at its origin. The use of the DGF allows the collocation at more than one point, permitting the implementation of a P-adaptive scheme in order to improve the accuracy of the solution without increasing the number of subregions. In our numerical simulations, the boundary conditions are imposed at the interpolation stencils in contact with the problem boundary instead of at the corresponding integration surfaces, permitting always the use of circular integration contours, even in regions near or in contact with the problem domain where the densities of the integrals are reconstructed from the interpolation formulae that already included the problem boundary conditions. [ABSTRACT FROM AUTHOR]

In this work we present an improvement of the Localized Regular Dual Reciprocity Method (LRDRM). LRDRM is an integral domain decomposition method with two distinguishing features, the boundary conditions are imposed at the local interpolation level and all the calculated integrals are regular. In this work we present an enhancement of this method where the interpolation functions themselves satisfy the partial differential equation to be solved. Results for 1D and 2D convection‐diffusion, 2D Helmholtz and 2D Poisson equations are presented, attaining accuracies two to three orders of magnitude higher than the original version of the LRDRM. [ABSTRACT FROM AUTHOR]

Immunologic causes for poor outcome of pregnancy complicated by primary cytomegalovirus (CMV) infection are only partially understood. Maternal and pup tumor necrosis factor (TNF) and natural killer cell (NK)‐like activity associated with primary gestational CMV infection initiated in either the first or third trimester equivalent in the inbred guinea pig model were investigated. Poor pregnancy outcome defined as fetal resorptions, premature delivery, stillbirths, and intrauterine growth retardation occurred with infection at either gestational time. Induction of TNF and NK activity by CMV infection during pregnancy correlated with resorptions in early pregnancy infection and with premature labor in late pregnancy infection. Stillbirths occurred with CMV infection at either time. Regardless of the gestational time of CMV acquisition, poor outcome correlated with higher maternal NK and TNF responses during the first weeks after maternal virus acquisition. Furthermore, CMV infected dams with loss of ≥ 50% of conceptus had higher TNF responses than infected dams with < 50% conceptus loss. Likewise, pups born in litters from CMV‐infected dams with resorptions and/or premature labor also had enhanced NK activity and TNF response to CMV compared with pups born to dams not having resorptions or premature labor. TNF responses in the delivered pups of infected dams were higher than from pups of uninfected dams regardless of litter outcome, whereas pup NK responses were enhanced only in pups from litters of dams with premature labor or resorptions. Enhanced NK and TNF activity appear to be associated with premature delivery and other poor outcomes of pregnancy. J. Med. Virol. 60:230–236, 2000. © 2000 Wiley‐Liss, Inc.

This study reports 8 years of personal experience in percutaneous nephrolithotripsy (PCNL) of complex renal calculosis. It is emphasised that even in this era of widespread use of extracorporeal lithotripsy (ESWL), PCNL is regaining importance in the more complex cases of renal calculosis, to try to reduce times for adequate stone clearance and to reach a better benefit/cost ratio. A success rate of 87.3% with monotherapy PCNL, 78.6% with debulking PCNL and 91.3% with associated PCNL-ESWL (programmed from the beginning or attempted out of necessity), has convinced us of the correct application we have given the method for treating complex renal calculosis.

Researchers' interest in the last few years has been concentrated on finding a medical, if possible, or at least “mini-invasive” therapy for benign prostatic hypertrophy (BPH), which can be used for the symptomatic form instead of open or endoscopic surgery. The various therapeutic options are reviewed, underlining their advantages and disadvantages.

— The Authors write about their experience with three cases of endoureteral prosthesis fragmentation during removal of the same. They review the various factors which may combine in making the materials of these prostheses more fragile. On the one hand they emphasise the necessity of preparing prophylactic measures for such an event, and on the other the central role of the urologist in the choice and management of the endoprosthesis.

This work presents a numerical study of the influence of different boundary conditions (BC) on the precision of the method of approximate particular solutions (MAPS) with radial basis functions in two dimensions. The state of the art merely mentions that the MAPS accuracy decreases near the boundaries. Therefore, the influence that the choice of boundary condition has on this method should be studied with more detail. The present analysis with numerical experiments was applied to the solution of homogeneous Stokes flow equations, backward facing step flow, Slip flow, convective flow between parallel vertical plates and to elliptic differential equations with variable coefficients. The results show that care must be taken in choosing the boundary conditions for this type of solution methods because this selection affects the precision of the results. It is shown that the error associated with Neumann boundary condition, can be reduced by using a refined nodal distribution towards the inlet and outlet zones. Conversely, mixed boundary conditions require careful combination of traction and velocity to achieve better accuracy with MAPS for some flow problems. [ABSTRACT FROM AUTHOR]