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81.
H Dodat E Denis G Pelizzo R Dubois P Carlioz Y Chavrier 《Canadian Metallurgical Quarterly》1998,8(1):58-61
Schwannomas are very rare in the nose and paranasal sinuses; their presence both intra-and extracranially is still rarer. Here we present a case of nasoethmoid schwannoma with intracranial extension into anterior cranial fossa. Clinical, radiological, pathological and operative findings are discussed and the literature is reviewed. We recommend bifrontal craniotomy for removal of intracranial and nasoethmoid extensions of this tumor. 相似文献
82.
D. Mathiot A. Lachiq A. Slaoui S. Noël J. C. Muller C. Dubois 《Materials Science in Semiconductor Processing》1998,1(3-4)
Limiting thermal exposure time using rapid thermal processing (RTP) has emerged as a promising simplified process for microelectronics applications and for manufacturing of terrestrial solar cells in a continuous way. Especially, rapid thermal diffusion (RTD) of phosphorus from doped oxide films (SOD) was extensively used for the emitter formation purpose but few work concerned the diffusion mechanism.Here we investigate more in details the diffusion kinetics of phosphorus after rapid thermal annealing of P-SOD coated silicon samples. The observed enhanced distribution of phosphorus after RTD is discussed based on the dopant sources and processing conditions. Comparisons between experimental profiles and simulation results using up to date phosphorus diffusion models allow us to discriminate between various possible enhancement mechanisms. 相似文献
83.
P Lanotte F Dubois S Le Pogam C Guerois B Fimbel Y Bacq Y Gruel A Goudeau F Barin 《Canadian Metallurgical Quarterly》1998,178(2):556-559
Several studies have reported the spontaneous loss of hepatitis C virus (HCV) antibodies in HCV-exposed persons. However, the relationship between seroreversion and spontaneous virus clearance has yet to be precisely determined in a single homogeneous population of untreated immunocompetent patients. In this study, 32 human immunodeficiency virus-seronegative hemophiliacs who had been exposed to HCV were followed for a mean duration of 141 months; 22 remained chronic carriers (68.8%). All but 1 of the nonviremic patients (90.0%) showed partial (8 cases) or complete (2 cases) seroreversion. In contrast, all but 1 of the viremic patients (95.1%) had a stable serologic profile when analyzed by a recombinant immunoblot assay. The results indicate that any HCV antibody-positive immunocompetent patient with no detectable serum HCV RNA and normal alanine aminotransferase values and whose serial samples show a progressive decrease in the level of HCV antibodies present may be considered as having a resolved infection. 相似文献
84.
B. Chetouane F. Dubois M. Vinches C. Bohatier 《International journal for numerical methods in engineering》2005,64(1):65-94
The aim of this paper is to present a discrete element approach for the study of stonework. In the present work, a masonry structure is considered as a collection of rigid or deformable blocks, interacting together by contact laws. In this paper, we use the non‐smooth contact dynamics (NSCD) resolution method mainly used for the modelling of granular media. In the considered masonry structures we define, on an elementary cell, average local strain and stress tensors. These definitions are valid under dynamical loading of the structure, taking into account rotations. We present their use on academic and on real masonry structures. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
85.
Cédric Baudrit Dominique Guyonnet Didier Dubois 《Canadian Metallurgical Quarterly》2005,131(12):1750-1754
In a previous paper in this Journal, a “hybrid method” was proposed for the joint propagation of probability distributions (expressing variability) and possibility distributions (i.e., fuzzy numbers, expressing imprecision or partial ignorance) in the computation of risk. In order to compare the results of the hybrid computation (a random fuzzy set) to a tolerance threshold (a tolerable level of risk), a postprocessing method was proposed. Recent work has highlighted a shortcoming of this postprocessing step which yields overly conservative results. A postprocessing method based on Shafer’s theory of evidence provides a rigorous answer to the problem of comparing a random fuzzy set with a threshold. The principles behind the new postprocessing scheme are presented and illustrated with a synthetic example. 相似文献
86.
Janie Dubois E. Neil Lewis Frederick S. Fry Jr. Elizabeth M. Calvey 《Food microbiology》2005,22(6):577-583
Near-infrared chemical imaging (NIR-CI) is investigated as a tool for the high-throughput analysis of self-contained microbial identification test cards for micro-organisms of concern in food. In this initial work, a NIR-CI system operating in the spectral range 1000–2350 nm was used to acquire NIR chemical images of bacterial cells deposited on a ‘card’, containing both the calibration and test samples. Results show that some bacteria can be identified from differences observed at unique wavelengths, and that a standard operating procedure can be developed for a particular ‘card’ to differentiate and hence identify the various organisms it contains using discrete wavelengths. For situations where a particular organism of concern is sought, a PLS chemometric model may offer better performance by accounting for variables that can be incorporated in the calibration without the need to know the taxonomic identity of the complete complement of bacteria present on the ‘card’. Overall, the NIR-CI results obtained in this investigation show that this high throughput technique possesses the specificity required to differentiate bacteria on the basis of their NIR spectra. 相似文献
87.
Cubic panoramas provide an efficient solution to the implementation of immersive and omnidirectional displays for image‐based virtual navigation. To allow unrestricted navigation through the environment, a system must be capable of constructing novel views given the reference images, typically, cubic panoramas. This paper proposes a processing pipeline for cubic panorama synthesis based on 2D/3D triangular reprojection. This pipeline uses matching features to implement the triangular meshing on cubic panoramas, and introduces the matching line constraint, which significantly reduces the artifacts of straight‐line features in the rendered image and accelerates the division process. The modules of this pipeline take the geometrical characteristics of cubic panorama into account. Thus, it can handle the discontinuities of the cube edges when the triangular mesh covers different faces. Furthermore, these modules could be reconfigured to compose customized pipelines and generate virtual cubic panoramas of different quality based on the amount of features. The performance and efficiency of the proposed pipeline is demonstrated with comparison experiments. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
88.
In the field of video protection, selective encryption (SE) is a scheme which ensures the visual security of a video by encrypting only a small part of the data. This paper presents a new SE algorithm for H.264/AVC videos in context-adaptive variable-length coding mode. This algorithm controls the amount of encrypted alternative coefficients (ACs) of the integer transform in the entropic encoder. Two visual quality measures, the peak signal-to-noise ratio (PSNR) and the structural similarity (SSIM), are used to measure the visual confidentiality level of each video frame and to control the amount of encrypted ACs. Moreover, a new psychovisual metric to measure the flickering is introduced, the so-called temporal structural similarity (TSSIM). This method can be applied on intra and inter frame video sequences. Several experimental results show the efficiency of the proposed method. 相似文献
89.
Gunaëlle Levallet Fatmh Dubois Arthur Leclerc Edwige Petit Lien Bekaert Maxime Faisant Christian Creveuil Evelyne Emery Grard Zalcman Emmanule Lechapt-Zalcman 《International journal of molecular sciences》2022,23(11)
IDH (isocitrate dehydrogenase) mutation, hypoxia, and neo-angiogenesis, three hallmarks of diffuse gliomas, modulate the expression of small non-coding RNAs (miRNA). In this paper, we tested whether pro-angiogenic and/or pro-hypoxic miRNAs could be used to monitor patients with glioma. The miRNAs were extracted from tumoral surgical specimens embedded in the paraffin of 97 patients with diffuse gliomas and, for 7 patients, from a blood sample too. The expression of 10 pro-angiogenic and/or pro-hypoxic miRNAs was assayed by qRT-PCR and normalized to the miRNA expression of non-tumoral brain tissues. We confirmed in vitro that IDH in hypoxia (1% O2, 24 h) alters pro-angiogenic and/or pro-hypoxic miRNA expression in HBT-14 (U-87 MG) cells. Then, we reported that the expression of these miRNAs is (i) strongly affected in patients with glioma compared to that in a non-tumoral brain; (ii) correlated with the histology/grade of glioma according to the 2016 WHO classification; and (iii) predicts the overall and/or progression-free survival of patients with glioma in univariate but not in a multivariate analysis after adjusting for sex, age at diagnosis, and WHO classification. Finally, the expression of miRNAs was found to be the same between the plasma and glial tumor of the same patient. This study highlights a panel of seven pro-angiogenic and/or pro-hypoxic miRNAs as a potential tool for monitoring patients with glioma. 相似文献
90.
Croccolo F Plantier F Galliero G Pijaudier-Cabot G Saghir MZ Dubois F Van Vaerenbergh S Montel F Bataller H 《The Review of scientific instruments》2011,82(12):126105
A thermodiffusion cell is developed for performing Soret experiments on binary mixtures at high pressure and in the presence of a porous medium. The cell is validated by performing experiments at atmospheric pressure. The experiments are performed by applying different temperature gradients to binary mixtures in order to determine their thermal contrast factor. These measurements provide a first demonstration of the good reproducibility of this kind of measurements upon calibration. 相似文献