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Analysis of a Prototypical Multiscale Method Coupling Atomistic and Continuum Mechanics:the Convex Case

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 209-216页

作者： xavier Blanc Claude le Bris Frédériclegoll Laboratoire J.L.-Lions Université Pierre et Marie CurieBoite courrier 187F-75252 ParisFrance CERMICS Ecole Nationale des Ponts et Chaussées 6 et 8 avenue Blaise PascalCité DescartesF-77455 Marne-la-Vallée and MICMACInria RocquencourtF-78153 Le ChesnayFrance CERMICS Ecole Nationale des Ponts et Chaussées 6 et 8 avenue Blaise PascalCité DescartesF-77455 Marne-la-Vallée and MICMACInria RocquencourtF-78153 Le ChesnayFrance EDF R & D1 avenue du Général de GaulleF-92140 ClamartFrance

In order to describe a solid which deforms smoothly in some region, but non smoothly in some other region, many multiscale methods have been recently proposed that aim at coupling an atomistic model （discrete mechanics） with a macroscopic model （continuum mechanics）. We provide here a theoretical basis for such a coupling in a one-dimensional setting, in the case of convex energy.

关键词： Multiscale methods variational problems continuum mechanics discrete mechanics

Mass Screening Using Antigenic and Molecular Diagnostic Tests of COVID-19 in Bangui at the Beginning of the Second Wave in July 2021

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Journal of Tuberculosis Research 2024年第1期12卷 1-12页

作者： Clotaire Donatien Rafaï Marie-Roseline Darnycka Belizaire Pierre Somse Wilfrid Sylvain Nambei Ernest Lango-Yaya Oscar Senzongo Luc Salva Hereidebona Ulrich Jeffrey Kotemossoua Rabbi Mermoz Senekian Simon Pounguinza Christian-Diamant Mossoro-Kpinde Alain le Faou Jean De Dieu Longo François-xavier Mbopi-Keou Gérard Grésenguet Boniface Koffi National Laboratory of Clinical Biology and Public Health Bangui Central African Republic Faculty of Health Sciences University of Bangui Bangui Central African Republic World Health Organization Bangui Central African Republic Ministry of Health and Population Bangui Central African Republic Faculty of Medicine Maieutic and Health Sciences University of Lorraine Pole Brabois Santé Nancy France Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroun

Objective: COVID-19 surveillance was established as early as March 2020 in the Central African Republic (CAR), after the WHO statement relating to the identification of several cases outside China. However, given the non-performing molecular biology technical platform in many developing countries in sub-Saharan Africa, the second wave promised to be surprising and formidable. In this context, a mass survey was launched in Bangui to determine the prevalence of COVID-19. Patients and Methods: From March 18 to April 2, 2021, a mass screening campaign took place in tourist places, companies and the main hospital infrastructures. Nasopharyngeal swab samples were collected from participants with and without symptoms of Influenza-like illness (ILI) and stored in VTM tubes. The Ag (COVID-19) and RT-PCR tests were carried out in Bangui at the LNBCSP. The sequencing of RT-PCR SARS-CoV-2 positives was carried out at the INRB. Results: We included 1480 participants of whom 33 (2.23%) were SARS-COV-2 positive, of whom 24 were male and 9 female. This sex difference was statistically significant (p = 0.012) as the sex ratio M/F was 1.09. Sampling sites located in the 1st arrondissement were the most prolific (p = 0.006) and were sequenced. In addition to the analysis of the 33 samples from the predefined sites under study, 17 control sequences from the provinces generated during the same period are added. We detected 2 Variants Of Concern (VOC) including the predominant B.1.620 (43.86%) followed by B.1.1.7 or Alpha (5.10%). Conclusion: The study showed the importance of surveillance and the availability of means of diagnosis of COVID-19. The identified risk factors were sex and sampling site. This study has shown the importance of setting up sentinel sites for COVID-19 surveillance in all regions of the country and the appropriate use of the anti-COVID-19 vaccine.

关键词： COVID-19 Variants Central African Republic

Relict glacial landscape in the Sierra Baguales Mountain Range(50°-51°S):evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes

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Journal of Mountain Science 2017年第2期14卷 282-295页

作者： ARAOS.JoséMiguel le roux.Jacobus Philiphus GUTIERREZ.Néstor Mauricio Department of Geology FCFMUniversidad de ChilePlaza Ercilla#803SantiagoChile Department of Geography Faculty of Social Sciences.Universidad Alberto HurtadoUienfuegos#41SantiagoChile Department of Geology FCFMUniversidad de Chile.Andean Geothermal Centre of ExcellencePlaza Ereilla#803SantiagoChile

The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range(SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field(SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift,which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum(LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower *** can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26m Equilibrium Line Altitude(ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio(AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography.

关键词： Glacial morphology Sierra Baguales Ice sheet glaciations Alpine glaciations Middle Holocene

Petrogenesis of the diamondiferous Pipe-8 ultramafic intrusion from the Wajrakarur kimberlite field of Southern India and its relation to the worldwide Mesoproterozoic(~1.1 Ga) magmatism of kimberlite and related rocks

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Geoscience Frontiers 2020年第3期11卷 793-805页

作者： Ashish Dongre K.S.Viljoen G.Belyanin Petrus le roux M.Malandkar Department of Geology Savitribai Phule Pune UniversityPune411007India Department of Geology University of JohannesburgP.O.Box 524Auckland Park2006South Africa Department of Geology University of Cape TownRondebosch7700South Africa Department of Geology Institute of ScienceAurangabad431004India

Detailed mineralogy,bulk rock major,trace and Sr-Nd isotope compositions,and ^(40)Ar/^(39)Ar dating of the Pipe-8 diamondiferous ultramafic intrusion in the Wajrakarur cluster of southern India,is *** on the presence of Ti-rich phlogopite,high Na/K content in amphibole,Al-and Ti-rich diopside,a titanomagnetite trend in spinel and the presence of Ti-rich schorlomite garnet and carbonates in the groundmass,the Pipe-8 intrusion is here more precisely classified as an ultramafic lamprophyre(i.e.,aillikite).An aillikite affinity of the Pipe-8 intrusion is further supported by the bulk rock major and trace element and Sr-Nd isotope ***-Nd isotope data are consistent with a common,moderately depleted upper mantle source region for both the Pipe-8 aillikite as well as the Wajrakarur kimberlites of southern India.A phlogopite-rich groundmass ^(40)Ar/^(39)Ar plateau age of 1115.8±7.9 Ma(2σ) for the Pipe-8 intrusion falls within a restricted 100 Ma time bracket as defined by the 1053-1155 Ma emplacement ages of kimberlites and related rocks in *** presence of ultramafic lamprophyres,carbonatites,kimberlites,and olivine lamproites in the Wajrakarur kimberlite field requires low degrees of partial melting of contrasting metasomatic assemblages in a heterogeneous sub-continental lithospheric *** widespread association of kimberlite and other mantle-derived magmatism during the Mesoproterozoic(ca.1.1 Ga) have been interpreted as being part of a single large igneous province comprising of the Kalahari,Australian,West Laurentian and Indian blocks of the Rodinia supercontinent that were in existence during its *** India only kimberlite/lamproite/ultramafic lamprophyre magmatism occurred at this time without the associated large igneous provinces as seen in other parts of *** may be because of the separated paleo-latitudinal position of India from Australia during the assembly of *** is speculated that the presence of a large

关键词： Kimberlite and related rocks Ultramafic lamprophyre Lamproites Wajrakarur kimberlite field Mantle plume Rodinia supercontinent

Chloramination of wastewater effluent: Toxicity and formation of disinfection byproducts

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Journal of Environmental Sciences 2017年第8期29卷 135-145页

作者： Julien le roux Michael J.Plewa Elizabeth D.Wagner Maolida Nihemaiti Azra Dad Jean-Philippe Croué leESU(UMR MA 102) Université Paris-Est–AgroParisTech Department of Crop Sciences the Global Safe Water InstituteUniversity of Illinois at Urbana-Champaign Curtin Water Quality Research Centre Department of ChemistryCurtin University US Food and Drug Administration National Center for Toxicological Research

The reclamation and disinfection of waters impacted by human activities（e.g., wastewater effluent discharges） are of growing interest for various applications but has been associated with the formation of toxic nitrogenous disinfection byproducts（N-DBPs）. Monochloramine used as an alternative disinfectant to chlorine can be an additional source of nitrogen in the formation of N-DBPs. Individual toxicity assays have been performed on many DBPs, but few studies have been conducted with complex mixtures such as wastewater effluents. In this work, we compared the cytotoxicity and genotoxicity of wastewater effluent organic matter（Ef OM） before and after chloramination. The toxicity of chloraminated Ef OM was significantly higher than the toxicity of raw Ef OM, and the more hydrophobic fraction（HPO）isolated on XAD-8 resin was more toxic than the fraction isolated on XAD-4 *** DBPs were also isolated on the XAD-8 resin. N-DBPs（i.e., haloacetonitriles or haloacetamides） were responsible for the majority of the cytotoxicity estimated from DBP concentrations measured in the XAD-8 and XAD-4 fractions（99.4% and 78.5%, respectively）.Measured DBPs accounted for minor proportions of total brominated and chlorinated products, which means that many unknown halogenated compounds were formed and can be responsible for a significant part of the toxicity. Other non-halogenated byproducts（e.g.,nitrosamines） may contribute to the toxicity of chloraminated effluents as well.

关键词： Disinfection byproducts Chloramination Toxicity Wastewater XAD resins Haloacetonitriles Haloacetamides

Local atomic structure evolution of liquid gadolinium and yttrium during solidification:An ab initio study

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Journal of Rare Earths 2023年第8期41卷 1265-1271,I0006页

作者： Qinghe Zheng Tao Hu Sébastien le roux Musen Li Chaoyue Chen Jianbo Yu Jiang Wang Wei Ren Zhongming Ren State Key Laboratory of Advanced Special Steels School of Materials Science and EngineeringDepartment of PhysicsInternational Center of Quantum and Molecular StructuresShanghai UniversityShanghai200444China University of Strasbourg Institut de Physique et Chimie des Matériaux de StrasbourgCNRSUMR 750423 rue du LoessStrasbourgF-67034France

Local atomic structure evolution of pure gadolinium(Gd)and yttrium(Y)during solidification was investigated by using ab initio molecular dynamics(AIMD)*** calculated results indicate that the local short-range order(SRO)in liquid Gd and Y is similar to some transitional metals with an asymmetric shape of the second peak in static structure ***,the formation of icosahedral local motifs as a function of temperature decreases the diffusivity,which explains the connection between structure evolution and dynamic *** examining the topological structures of both systems,we demonstrate that small atomic displacement leads to two different types of topological sixfold rings in liquid and solid *** analyses yield a systematic study about rare earth metals Gd and Y at the atomic level.

关键词： Atomic structure evolution Rare earth Ab initio molecular dynamics Solidification

Statins for primary cardiovascular prevention in the elderly

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Journal of Geriatric Cardiology 2015年第4期12卷 431-438页

作者： Juan Pedro-Botet Elisenda Climent Juan J Chillarón Rocio Toro David Benaiges Juana A Flores-le roux Lipid and Vascular Risk Unit Endocrinology department Hospital del Mar. Spain Department of Medicine School of Medicine. Cáldiz University Cádiz Spain

The elderly population is increasing worldwide, with subjects 〉 65 years of age constituting the fastest-growing age group. Furthermore, the elderly face the greatest risk and burden of cardiovascular disease mortality and morbidity. Although elderly patients, particularly those older 〉 75, have not been well represented in randomized clinical trials evaluating lipid-lowering therapy, the available evidence supporting the use of statin therapy in primary prevention in older individuals is derived mainly from subgroup analyses and post-hoc data. On the other hand, elderly patients often have multiple co-morbidities that require a high number of concurrent medications; this may increase the risk for drug-drug interactions, thereby reducing the potential benefits of statin therapy. The aim of this review was to present the relevant literature regarding statin use in the elderly for theft primary cardiovascular disease, with the associated risks and benefits of treatment.

关键词： Cardiovascular disease Dyslipidaemia Elderly Primary prevention Statins

Response of life-history traits to artificial and natural selection for virulence and nonvirulence in a Drosophila parastitoid, Asobara tabida

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Insect Science 2018年第2期25卷 317-327页

作者： Joffrey Moiroux Joan van Baaren Mathilde Poyet Aude Couty Patrice Eslin Genevieve Prevost Jeremy Sguin Vincent le roux FRE 3498 EDYSAN CNRS-Universite de Picardie Jules Verne 33 rue St Leu Amiens Cedex France UMR 6553 ECOBIO CNRS- Universite Rennes 1 Campus de Beaulieu avenue du G~n~ral Leclerc Rennes Cedex France UMR 7263 IMBE AMU - CNRS - IRD - UAPV Universite d＇Avignon et des Pays de Vaucluse 301 rue Baruch de Spinoza 84916 Avignon Cedex 09 Franc

Co-evolution of host-parasitoid interactions is determined by the costs of host resistance, which received empirical evidence, and the costs ofparasitoid virulence, which have been mostly hypothesized. Asobara tabida is a parasitoid, which mainly parasitizes Drosophila melanogaster and D. subobscura, the first species being able to resist to the parasitoid development while the second species is not. To parasitize resistant hosts, including D. melanogaster, A. tabida develops sticky eggs, which prevent encapsulation, but this virulence mechanism may be costly. Interindividual and interpopulation variation in the proportion of sticky eggs respectively allowed us to （i） artificially select and compare life-history traits of a virulent and a nonvirulent laboratory strain, and （ii） compare a virulent and a nonvirulent field strain, to investigate the hypothetical costs of virulence. We observed strong differences between the 2 laboratory strains. The nonvirulent strain invested fewer resources in reproduction and walked less than the virulent one but lived longer. Concerning the field strains, we observed that the nonvirulent strain had larger wings while the virulent one walked more and faster. All together, our results suggest that virulence may not always be costly, but rather that different life histories associated with different levels of virulence may coexist at both intra- and interDoDulation levels.

关键词： encapsulation geographic variation host resistance trade-offs

Multidisciplinary management of Mirizzi syndrome with cholecystobiliary fistula: the value of minimally invasive endoscopic surgery

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Hepatobiliary & Pancreatic Diseases International 2015年第5期14卷 543-547页

作者： Fabien le roux Charles Sabbagh Brice Robert Thierry Yzet Laurent Dugue Jean-Paul Joly Jean-Marc Regimbeau Department of Digestive and Oncological Surgery Amiens University Hospital Jules Verne University of Picardie Department of Interventional and Diagnostic Imaging Amiens University Hospital Jules Verne University of Picardie Department of Digestive Surgery Saint-Camille Hospital Department of Hepatogastroenterology Amiens University Hospital Jules Verne University of Picardie

Mirizzi syndrome, a rare complication of gallstones, is defined by obstruction of the main bile duct. This obstruction may worsen and thus result in cholecystobiliary fistula. Surgical management of Mirizzi syndrome is complicated by the presence of inflamed tissue around the hepatic pedicle, making it impossible to distinguish between the main bile duct and the gallbladder. The surgeon＇s first task is to perform subtotal cholecystotomy（from the fundus of the gallbladder to the neck） without trying to locate the cystic duct. In a second step, the gallstones are extracted and the main bile duct is then repaired. In most cases, a T-tube is used to drain the main bile duct, and abdominal drainage is left in place（in case a bile fistula forms）. This study concluded that preoperative drainage of the main bile duct in the treatment of Mirizzi syndrome types II and III is feasible and might help to decrease the postoperative complication rate.

关键词： jaundice Mirizzi syndrome cholecystobiliary fistula endoscopic treatment cholecystectomy T-tube drain