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Communications in Computational Physics 2014年第9期16卷 841-891页

作者： Pascal Jacq pierre-henri maire Remi Abgrall CEA/CESTA 15 Avenue des Sablieres CS 6000133116 Le Barp cedexFrance. Institut fur Mathematik Universitat ZurichCH-8057 ZurichSwitzerland.

We present a finite volume based cell-centered method for solving diffusion equations on three-dimensional unstructured grids with general tensor *** main motivation concerns the numerical simulation of the coupling between fluid flows and heat *** corresponding numerical scheme is characterized by cell-centered unknowns and a local ***,the scheme results in a global sparse diffusion matrix,which couples only the cell-centered *** space discretization relies on the partition of polyhedral cells into sub-cells and on the partition of cell faces into *** is characterized by the introduction of sub-face normal fluxes and sub-face temperatures,which are auxiliary unknowns.A sub-cellbased variational formulation of the constitutive Fourier law allows to construct an explicit approximation of the sub-face normal heat fluxes in terms of the cell-centered temperature and the adjacent sub-face *** elimination of the sub-face temperatures with respect to the cell-centered temperatures is achieved locally at each node by solving a small and sparse linear *** system is obtained by enforcing the continuity condition of the normal heat flux across each sub-cell interface impinging at the node under *** parallel implementation of the numerical algorithm and its efficiency are described and *** accuracy and the robustness of the proposed finite volume method are assessed by means of various numerical test cases.

关键词： Finite volume methods unstructured grids anisotropic diffusion parallel computing

Staggered Lagrangian Discretization Based on Cell-Centered Riemann Solver and Associated Hydrodynamics Scheme

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Communications in Computational Physics 2011年第9期10卷 940-978页

作者： pierre-henri maire Raphael Loubere Pavel Vachal CEA-CESTA BP 233114Le BarpFrance Institut de Mathematiques de Toulouse(IMT)Universite Paul-Sabatier and CNRS ToulouseFrance FNSPE Czech Technical University(CTU)in PragueCzech Republic

The aim of the present work is to develop a general formalism to derive staggered discretizations for Lagrangian hydrodynamics on two-dimensional unstructured *** this end,we make use of the compatible discretization that has been initially introduced by *** et al.,in ***.,146(1998).Namely,momentum equation is discretized by means of subcell forces and specific internal energy equation is obtained using total energy *** main contribution of this work lies in the fact that the subcell force is derived invoking Galilean invariance and thermodynamic *** is,we deduce a general form of the sub-cell force so that a cell entropy inequality is *** subcell force writes as a pressure contribution plus a tensorial viscous contribution which is proportional to the difference between the nodal velocity and the cell-centered *** cell-centered velocity is a supplementary degree of freedom that is solved by means of a cell-centered approximate Riemann *** satisfy the second law of thermodynamics,the local subcell tensor involved in the viscous part of the subcell force must be symmetric positive *** subcell tensor is the cornerstone of the *** particular expression of this tensor is given.A high-order extension of this discretization is *** tests are presented in order to assess the efficiency of this *** results obtained for various representative configurations of one and two-dimensional compressible fluid flows show the robustness and the accuracy of this scheme.

关键词： Lagrangian scheme Riemann solver artificial viscosity hydrodynamics compressible flow

A Multi-Material CCALE-MOF Approach in Cylindrical Geometry

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Communications in Computational Physics 2014年第2期15卷 330-364页

作者： Marie Billaud Friess Jerome Breil pierre-henri maire Mikhail Shashkov LUNAM Universite GeMUMR CNRS 6183Ecole Centrale NantesUniversite de Nantes1 rue de la NoeBP 9210144321 Nantes Cedex 3France Univ.Bordeaux CEACNRSCELIAUMR5107F-33400 TalenceFrance CEA CESTA 15 Avenue des Sabli`eresCS 6000133116 Le Barp CedexFrance Los Alamos National Laboratory XCP-4Los AlamosNM 87545USA.

In this paper we present recent developments concerning a Cell-Centered Arbitrary Lagrangian Eulerian(CCALE)strategy using the Moment Of Fluid(MOF)interface reconstruction for the numerical simulation of multi-material compressible fluid flows on unstructured grids in cylindrical ***,our attention is focused here on the following ***,we propose a new formulation of the scheme used during the Lagrangian phase in the particular case of axisymmetric ***,the MOF method is considered for multi-interface reconstruction in cylindrical ***,a method devoted to the rezoning of polar meshes is ***,a generalization of the hybrid remapping to cylindrical geometries is *** explorations are validated by mean of several test cases using unstructured grid that clearly illustrate the robustness and accuracy of the new method.

关键词： Cell-centered scheme Lagrangian hydrodynamics ALE MOF interface reconstruction Rezoning algorithm polar meshes hybrid remapping axisymmetric geometries.

Evaluation of the Strategy and Efficacy of Treatment of Chronic Viral Hepatitis C with the Sofosbuvir/Daclatasvir Combination in a Resource-Limited Country

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Open Journal of Gastroenterology 2024年第7期14卷 233-240页

作者： Mayanna Habkreo Ali Mahamat Moussa Adama Ahmed Ngare Abdraman Kossou Tahir Mahamat Saleh maire Dehainsala Mahamat Ali Hachim Mahamat Ali Bolti Oumaima Djarma Joseph Madtoingue Service de Gastroentrologie/Mdecine Interne du Centre Hospitalier Universitaire la Rfrence Nationale NDjamena Chad Service de Gastroentrologie du Centre Hospitalier Universitaire la Renaissance NDjamena Chad Service de Maladies Infectieuses du Centre Hospitalier Universitaire la Renaissance NDjamena Chad Service de Maladies Infectieuses du Centre Hospitalier Universitaire la Rfrence Nationale NDjamena Chad

Introduction: The treatment of viral hepatitis C (HCV), a major public health problem, has evolved considerably since the introduction of direct-acting anti-virals (DAAs). The aim of this study was to evaluate the strategy for initiating treatment with Sofosbuvir/Daclatasvir, and also to assess its efficacy. Patients and Methods: Included were patients aged at least 15 years, with detectable hepatitis C viremia and treated with a pan-genotypic Sofosbuvir/Daclatasvir regimen at the Centre “Hospitalier Universitaire la Référence Nationale de N’Djamena” between October 2019 and October 2023. The APRI score was used to assess fibrosis. Cure was defined by an undetectable viral load 12 weeks after the end of treatment. Results: A total of 835 patients were included (sex ratio 1.55, mean age 50.5 ± 13.73, extremes 20 and 84 years). The 60 - 69 age group was the most represented. The mean APRI score was 0.42 ± 0.29, with extremes of 0.019 and 1.84. The mean viral load was 2,316,193.086 IU/mL. All subjects had good renal function. Cytolysis was absent in 70% of cases. Without genotyping, a pan-genotypic regimen was used in all patients: Sofosbuvir (400 mg)/Daclatasvir (60 mg). The cure rate was 99.4%, with good tolerability. However, four cases of failure were recorded out of the 668 patients who underwent follow-up HCV-PCR testing after 12 weeks of treatment. Conclusion: The Sofosbuvir/Daclatasvir regimen is highly effective, with an excellent safety profile. However, the still high cost of these molecules limits their accessibility to a large proportion of patients.

关键词： Efficacy Tolerance Sofosbuvir/Daclatasvir HCV Chad

Insecurity by Design: Today's Io T Device Security Problem

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Engineering 2016年第1期2卷 48-49页

作者： maire O’Neill Secure Digital Systems at the Center for Secure Information Technologies (CSIT) Queen’s University Belfast

In today＇s technological age someone could gain access to your online bank account through a light bulb. This is due to the Intemet of Things （IoT）. The loT has become a reality as more and more of our devices are being connected to the Internet. In fact, automated teller machines （ATMs） have been online for many years, and more recently we have had the installation of smart meters remotely connecting to the electricity grid. We now have smart watches and smart baby monitors, and there are many more examples of new loT devices.

关键词：安全问题设备设计远程连接智能电表自动取款机科技时代银行账户

Role of endoscopic ultrasound in the screening and follow-up of high-risk individuals for familial pancreatic cancer

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World Journal of Gastroenterology 2019年第34期25卷 5082-5096页

作者： Diane Lorenzo Vinciane Rebours Frédérique maire Maxime Palazzo Jean-Michel Gonzalez Marie-pierre Vullierme Alain Aubert Pascal Hammel Philippe Lévy Louis de Mestier Pancreatology Department Beaujon HospitalAssistance Publique-Hopitaux de ParisClichyand Paris Diderot UniversityParis 75013France INSERM UMR1149Paris 92110France Departement of Gastroenterology Aix Marseille university-APHM-Hopital NordMarseille 13000France Radiology Department Beaujon HospitalAssistance Publique-Hopitaux de ParisClichyand Paris Diderot UniversityParis 92110France Oncology Department Beaujon HospitalAssistance Publique-Hopitaux de ParisClichyand Paris Diderot UniversityParis 92110France

Managing familial pancreatic cancer(FPC)is challenging for gastroenterologists,surgeons and ***-risk individuals(HRI)for pancreatic cancer(PC)(FPC or with germline mutations)are a heterogeneous group of subjects with a theoretical lifetime cumulative risk of PC over 5%.Screening is mainly based on annual magnetic resonance imaging(MRI)and endoscopic ultrasound(EUS).The goal of screening is to identify early-stage operable cancers or high-risk precancerous lesions(pancreatic intraepithelial neoplasia or intraductal papillary mucinous neoplasms with high-grade dysplasia).In the literature,target lesions are identified in 2%-5%of HRI who undergo *** appears to provide better identification of small solid lesions(0%-46%of HRI)and chronicpancreatitis-like parenchymal changes(14%-77%of HRI),while MRI is probably the best modality to identify small cystic lesions(13%-49%of HRI).There are no specific studies in HRI on the use of contrast-enhanced harmonic *** can also be used to obtain tissue ***,there is still limited evidence on the accuracy of imaging procedures used for screening or agreement on which patients to *** cost-effectiveness of screening is also *** new EUS-related techniques,such as searching for DNA abnormalities or protein markers in pancreatic fluid,appear to be promising.

关键词： Endoscopic ultrasound Familial pancreatic cancer Fine-needle aspiration Intraductal papillary mucinous neoplasm Pancreatic cancer Pancreatic intraepithelial neoplasia Pancreatic cancer screening guidelines

关于全球冷暖和亚、非夏季风区干湿变迁之联系的一个述评

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地理学报 1995年第5期50卷 471-479页

作者：严中伟 maire,NP 中国科学院大气物理研究所

基于近年来的多种资料分析结果，讨论了不同时间尺度上全球热状况之于中国东部和其它低纬亚非夏季风影响区干湿变迁的宏观控制作用。指出：在百年以上时间尺度上，全球暖而夏季风强从而导致有关区域多雨偏湿，全球冷则夏季风区域多偏干... 详细信息

基于近年来的多种资料分析结果，讨论了不同时间尺度上全球热状况之于中国东部和其它低纬亚非夏季风影响区干湿变迁的宏观控制作用。指出：在百年以上时间尺度上，全球暖而夏季风强从而导致有关区域多雨偏湿，全球冷则夏季风区域多偏干；但较短时间尺度上的全球性冷暖波动往往不足以使各地的夏季风系统和干湿状况产生一致响应。

关键词：全球变化区域干湿季风气候变化

Using a stand-level model to predict light absorption in stands with vertically and horizontally heterogeneous canopies

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Forestry Studies in China 2014年第3期16卷 158-176页

作者： David I Forrester Ruben Guisasola Xiaolu Tang Axel T Albrecht Tran Lam Dong Guerric le maire Chair of Silviculture Faculty of Environment and Natural ResourcesFreiburg University Chair of Forest Inventory and Remote Sensing Georg-August-Universitt Gttingen Forest Research Institute of Baden-Wrttemberg Tasmanian Institute of Agriculture(TIA) Vietnamese Academy of Forest Sciences Silviculture Research Institute CIRAD UMR Eco & Sols2 Place VialaMontpellier 34060France

Background： Forest ecosystem functioning is strongly influenced by the absorption of photosynthetically active radiation （APAR）, and therefore, accurate predictions of APAR are critical for many process-based forest growth models. The Lambert-Beer law can be applied to estimate APAR for simple homogeneous canopies composed of one layer, one species, and no canopy gaps. However, the vertical and horizontal structure of forest canopies is rarely homogeneous. Detailed tree-level models can account for this heterogeneity but these often have high input and computational demands and work on finer temporal and spatial resolutions than required by stand-level growth models. The aim of this study was to test a stand-level light absorption model that can estimate APAR by individual species in mixed-species and multi-layered stands with any degree of canopy openness including open-grown trees to closed canopies. Methods： The stand-level model was compared with a detailed tree-level model that has already been tested in mixed-species stands using empirical data. Both models were parameterised for five different forests, including a wide range of species compositions, species proportions, stand densities, crown architectures and canopy structures. Results： The stand-level model performed well in all stands except in the stand where extinction coefficients were unusually variable and it appears unlikely that APAR could be predicted in such stands using （tree- or stand-level） models that do not allow individuals of a given species to have different extinction coefficients, leaf-area density or analogous parameters. Conclusion： This model is parameterised with species-specific information about extinction coefficients and mean crown length, diameter, height and leaf area. It could be used to examine light dynamics in complex canopies and in stand-level growth models.

关键词： Complex forests Mixed-species Stand structure Extinction coefficient Lambert-Beer law Light absorption

Resection and reconstruction of pelvic and extremity soft tissue sarcomas with major vascular involvement: Current concepts

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World Journal of Orthopedics 2016年第5期7卷 293-300页

作者： Niall P Mc Goldrick Joseph S Butler maire Lavelle Stephen Sheehan Sean Dudeney Gary C O'Toole National Sarcoma Service Department of Trauma and Orthopaedic Surgery St Vincent’s University Hospital Department of Histopathology St Vincent’s University Hospital Department of Vascular Surgery St Vincent’s University Hospital

Soft tissue sarcoma accounts for approximately 1% of all cancers diagnosed annually in the United States. When these rare malignant mesodermal tumours arise in the pelvis and extremities, they may potentially encase or invade large calibre vascular structures. This presents a major challenge in terms of safe excision while also leaving acceptable surgical margins. In recent times, the trend has been towards limb salvage with vascular reconstruction in preference to amputation. Newer orthopaedic and vascular reconstructive techniques including both synthetic and autogenous graft reconstruction have made complex limb-salvage surgery feasible. Despite this, limb-salvage surgery with concomitant vascular reconstruction remains associated with higher rates of post-operative complications including infection and amputation. In this review we describe the initial presentation and investigation of patients presenting with soft tissue sarcomas in the pelvis and extremities, which involve vascular structures. We further discuss the key surgical reconstructive principles and techniques available for the management of these complex tumours, drawn from our institution's experience as a national tertiary referral sarcoma service.

关键词： Sarcoma Extremities Vascular surgical procedures Limb salvage Reconstruction

Mitigating nitrous oxide emissions from agricultural soils by precision management

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Frontiers of Agricultural Science and Engineering 2020年第1期7卷 75-80页

作者： Robert M.REES Juliette maire Anna FLORENCE Nicholas COWAN Ute SKIBA Tony van der WEERDEN Xiaotang JU Scotland's Rural College EdinburghScotlandEH93JGUK Centre for Ecology and Hydrology Bush EstatePenicuikScotlandEH26 OQBUK AgResearch Invermay Agricultural CentreMosgiel 9053New Zealand College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China

Nitrous oxide(N2O)emissions make up a significant part of agricultural greenhouse gas *** is an urgent need to identify new approaches to the mitigation of these emissions with emerging *** this short review four approaches to precision managements of agricultural systems are described based on examples of work being undertaken in the UK and New *** offer the opportunity for N2 O mitigation without any reduction in *** approaches depend upon new sensor technology,modeling and spatial information with which to make management decisions and interventions that can both improve agricultural productivity and environmental protection.

关键词： decision support systems mitigation nitrous oxide precision farming