51 research outputs found
Leiomyosarcome du Rein: A Propos D’un Cas
Le léiomyosarcome du rein est une tumeur rare. Les auteurs ont rapporté l’observation d’un homme âgé de 45 ans, chez lequel le diagnostic d’une tumeur rétropéritoénale gauche a été posé lors de l’exploration de douleurs du flanc gauche associées à une altération de l’état général et ce par l’imagerie (Echographie et scanner abdominal). La laparotomie exploratrice avait conclu à une tumeur rénale gauche localement évoluée, une néphrectomie élargie a été réalisée et l’histologie était en faveur d’un léiomyosarcome rénal. Une récidive locale a été diagnostiquée après un recul de 6 mois. Après une nouvelle laparotomie, l’abstention était de mise devant le caractère évolué de la récidive. Le but de cette observation est double. Le premier, est la nécessité de faire un diagnostic précoce, afin d’intervenir sur une tumeur de petite taille, plus accessible à la chirurgie. Le second, est de discuter la place du traitement adjuvant, qui pourrait réduire le risque de récidive précoce.Mots clés : Léiomyosarcome, rei
A biclustering algorithm based on a Bicluster Enumeration Tree: application to DNA microarray data
<p>Abstract</p> <p>Background</p> <p>In a number of domains, like in DNA microarray data analysis, we need to cluster simultaneously rows (genes) and columns (conditions) of a data matrix to identify groups of rows coherent with groups of columns. This kind of clustering is called <it>biclustering</it>. Biclustering algorithms are extensively used in DNA microarray data analysis. More effective biclustering algorithms are highly desirable and needed.</p> <p>Methods</p> <p>We introduce <it>BiMine</it>, a new enumeration algorithm for biclustering of DNA microarray data. The proposed algorithm is based on three original features. First, <it>BiMine </it>relies on a new evaluation function called <it>Average Spearman's rho </it>(ASR). Second, <it>BiMine </it>uses a new tree structure, called <it>Bicluster Enumeration Tree </it>(BET), to represent the different biclusters discovered during the enumeration process. Third, to avoid the combinatorial explosion of the search tree, <it>BiMine </it>introduces a parametric rule that allows the enumeration process to cut tree branches that cannot lead to good biclusters.</p> <p>Results</p> <p>The performance of the proposed algorithm is assessed using both synthetic and real DNA microarray data. The experimental results show that <it>BiMine </it>competes well with several other biclustering methods. Moreover, we test the biological significance using a gene annotation web-tool to show that our proposed method is able to produce biologically relevant biclusters. The software is available upon request from the authors to academic users.</p
Correlation of HER-2 over-expression with clinico-pathological parameters in Tunisian breast carcinoma
Effect of sputtering power on the electrical and optical properties of Ca-doped ZnO thin films sputtered from nanopowders compacted target
International audienceIn the present work, we have deposited calcium doped zinc oxide thin films by magnetron sputtering technique using nanocrystalline particles elaborated by sol–gel method as a target material. In the first step, the nanoparticles were synthesized by sol–gel method using supercritical drying in ethyl alcohol. The structural properties studied by X-ray diffractometry indicates that Ca doped ZnO has a polycrystalline hexagonal wurzite structure with a grain size of about 30 nm. Transmission electron microscopy (TEM) measurements have shown that the synthesized CZO is a nanosized powder. Then, thin films were deposited onto glass substrates by rf-magnetron sputtering at ambient temperature. The influence of RF sputtering power on structural, morphological, electrical, and optical properties were investigated. It has been found that all the films deposited were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (0 0 2) crystallographic direction. They have a typical columnar structure and a very smooth surface. The as-deposited films show a high transmittance in the visible range over 85% and low electrical resistivity at room temperature
Influence of sputtering power on the properties of thin layers of GZO for photovoltaic applications
International audienceIn the present work, we have deposited gallium doped zinc oxide thin films by magnetron sputtering technique based nanocrystalline particles elaborated by sol–gel method. In the first step, the nanoparticles were synthesized by sol–gel method using supercritical drying in ethyl alcohol. The structural studied by X-ray diffractometry indicates that GZO has a polycrystalline hexagonal wurzite structure with a grain size of about 30 nm. Transmission electron microscopy measurements have shown that very small particles of GZO are present in the aerogel powder. Then, thin films were deposited onto glass substrates by rf-magnetron sputtering at ambient temperature. The influence of RF sputtering power on structural, morphological, electrical, and optical properties were investigated. It has been found that all of the films deposited were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (002) crystallographic direction. The film deposited at 60 W showed the lowest electrical resistivity of 3.5 × 10−3 Ω cm achieved through the highest Hall mobility of 9.30 cm2 V−1 s−1. All the GZO films in this study showed the optical transmittances higher than 80 %
Sputtered Al-doped ZnO transparent conducting thin films suitable for silicon solar cells
International audienceHighly transparent conducting Al-doped zinc oxide (AZO) thin films have been grown onto p-type porous silicon substrates by RF-magnetron sputtering at room temperature using aluminum doped nanocrystalline powder. The obtained AZO films were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (002) crystallographic direction. The films are highly transparent in the visible wavelength region with a transmittance higher than 85% and an electrical resistivity of 1.56 × 10− 4 Ω·cm was obtained at room temperature. On the other hand, we have studied the position of the p–n junction involved in the In2O3:SnO2/(n)AZO/Si(p) structure, by electron-beam induced current technique. Current density–voltage characterizations in dark and under illumination were also investigated. The cell exhibits an efficiency of 5%
Study of CuS Thin Films for Solar Cell Applications Sputtered from Nanoparticles Synthesised by Hydrothermal Route
Preparation and characterization of n-type conductive (Al, Co) co-doped ZnO thin films deposited by sputtering from aerogel nanopowders
International audienceHighly transparent, n-type conducting ZnO thin films were obtained by low temperature magnetron sputtering of (Co, Al) co-doped ZnO nanocrystalline aerogels. The nanoparticles of similar to 30 nm size were synthesized by a sol-gel method using supercritical drying in ethyl alcohol. The structural, optical and electrical properties of the films were investigated. The ZnO films were polycrystalline textured, preferentially oriented with the (0 0 2) crystallographic direction normal to the film plane. The films show within the visible wavelength region an optical transmittance of more than 90% and a low electrical resistivity of 3.5 x 10(-4) Omega cm at room temperature. (c) 2007 Elsevier B.V. All rights reserved
Optical, electrical and magnetic properties of transparent, n-type conductive Zn0.90-x,V0.10AlxO thin films elaborated from aerogel nanoparticles
International audienceVanadium-aluminium co-doped ZnO thin films have been grown by rf-magnetron sputtering of Zn0.90-xV0.10AlxO (x = 0.01 to 0.03) aerogel nanoparticles. Even though the films were deposited at room temperature they were of good crystal quality and showed c-axis texturing normal to the film surface. The films are highly transparent in the visible with a transmittance higher than 90%. The highest conductivity of 5.10(3) Omega(-1) cm(-1) is obtained for 1% Al doping. The incorporation of V, a notoriously difficult dopant in ZnO, is confirmed by the observation of different absorption bands near 800 nm which we attribute to intracenter transitions of Zn substituted V2+. The magnetic properties of the aerogel particles have been studied by electron paramagnetic resonance (EPR) spectroscopy. No evidence for a ferromagnetic phase is found contrary to theoretical predictions. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei
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