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Role of the rhizosphere of a flooding-tolerant herb in promoting mercury methylation in water-level fluctuation zones

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Journal of Environmental sciences 2022年第9期34卷 139-151页

作者： Juan Wang Yuping Xiang Xiaosong Tian Cheng Zhang Guiqing Gong Jinping Xue Tao Jiang Dingyong Wang Yongmin Wang Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China laboratory of Environmental Nanotechnology&Health Effect Chinese Academy of SciencesResearch Center for Eco-Environmental SciencesBeijing 100085China College of Resources and Safety Chongqing Vocational Institute of EngineeringChongqing 402260China institut des sciences analytiques et des physico-chimie pour l’environnement et les materiaux(IPREM) UMR 5254CNRSUniversitede Pau et des Pays de l’AdourPau 64000France

The water-level fluctuation zone(WlFZ) has been considered as a hotspot for mercury(Hg) methylation. Flooding-tolerant herbs are gradually acclimated to this water-land ecotone, tending to form substantial root systems for improving erosion resistance. Accompanying rhizosphere microzone plays crucial but unclear roles in methylmercury(Me Hg) formation in the WlFZ. Thus, we conducted this study in the WlFZ of the Three Gorges Reservoir, to explore effects of the rhizosphere of a dominant flooding-tolerant herb(bermudagrass) on Me Hg production. The elevated Hg and Me Hg in rhizosphere soils suggest that the rhizosphere environment provides favorable conditions for Hg accumulation and methylation. The increased bioavailable Hg and microbial activity in the rhizosphere probably serve as important factors driving Me Hg formation in the presence of bermudagrass. Simultaneously, the rhizosphere environments changed the richness, diversity, and distribution of hgc A-containing microorganisms. Here, a typical ironreducing bacterium( Geobacteraceae) has been screened, however, the majority of hgc A genes detected in rhizosphere, near-, and non-rhizosphere soils of the WlFZ were unclassified. Collectively, these results provide new insights into the elevated Me Hg production as related to microbial processes in the rhizosphere of perennial herbs in the WlFZ, with general implications for Hg cycling in other ecosystems with water-level fluctuations.

关键词： Three Gorges Reservoir Water-level fluctuation zone Rhizosphere soil Methylmercury Mercury methylator

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Asphaltene aggregation studied by molecular dynamics simulations:role of the molecular architecture and solvents on the supramolecular or colloidal behavior

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Petroleum science 2019年第3期16卷 669-684页

作者： H.Santos Silva A.Alfarra G.Vallverdu D. Begue B.Bouyssiere I.Baraille institut des science analytiques et physico-chimie pour l'environnement et les materiaux UMR 5254 CNRS/Univ Pau and Pays Adour 64000 Pau France Total Research and Technology BP 2776700 Gonfreville Harfleur France Joint laboratory C2MC: Complex Matrices Molecular Characterization Total Research and Technology BP 2776700 Gonfreville Harfleur France

Asphaltene aggregation is a subject under vivid discussion:There are several parameters one needs to determine before its behavior can be mastered and better target solutions can be *** nature of asphaltene aggregation(colloidal or supramolecular)and the role of solvents and their mixtures are among the least understood parameters in asphaltene *** paper addresses molecular dynamic simulations to correlate the aggregation properties of asphaltenes,their molecular structure and the concentration of these *** show that the formation of the nanoaggregate depends,primarily,on the size of the conjugated core and on the eventual presence of polar groups capable of forming *** on the conjugated core do not change their shape or type of aggregation but may induce stronger π-π *** macroaggregation formation depends upon the length of the lateral chains of asphaltenes and also on the presence of polar groups at its ***,n-heptane and water may interact selectively with asphaltenes in function of their molecular *** this fact and the aggregation behavior observed,we advocate toward the assumption that a colloidal behavior of asphaltenes might be a particular case of a more general model,based on a supramolecular description.

关键词： Asphaltenes Molecular dynamics Aggregation Heavy oil

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Role of the porphyrins and demulsifiers in the aggregation process of asphaltenes at water/oil interfaces under desalting conditions:a molecular dynamics study

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Petroleum science 2020年第3期17卷 797-810页

作者： H.Santos Silva A.Alfarra G.Vallverdu D.Bégué B.Bouyssiere I.Baraille institut des science analytiques et physico-chimie pour l’environnement et les materiaux UMR 5254CNRS/Univ Pau&Pays Adour64000 PauFrance Total Research and Technology GonfrevilleBP 2776700 HarfleurFrance Joint laboratory C2MC:Complex Matrices Molecular Characterization Total Research and TechnologyGonfrevilleBP 2776700 HarfleurFrance

Breaking water-in-oil emulsions during the refining of crude oils is an important step before any upgrading process is *** molecules are incriminated as playing an important role in this *** the mechanisms behind the affinity between them and water is a key step to understand how to break these emulsions more easily and require lower amounts of *** which demulsifier molecule(s)to use is also primordial,but to do so rationally,one needs to know which are the molecular interactions in place between asphaltenes,porphyrins and water so that demulsifiers are chosen to destabilize a specific physical–chemical *** this paper,we study the interactions arising between asphaltenes and porphyrins and six different molecules potentially displaying a demulsification action in the presence of water/oil *** demonstrate that the ionic demulsifier molecules present an interesting potential to either interact strongly with water,replacing asphaltenes in this interaction,or to interact with the active sites of asphaltenes,deactivating them and avoiding any asphaltenic interfacial ***,we also found that although asphaltenes do not migrate spontaneously toward the water/oil interfaces,porphyrins do so rather *** indicates that porphyrins do have an important activity at the water/oil interface.

关键词： Asphaltenes aggregation Petroporphyrins Molecular dynamics Emulsion Water-oil interface Demulsifiers

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Third-order nonlinear optical susceptibility of crystalline oxide yttria-stabilized zirconia

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Photonics Research 2020年第2期8卷 110-120页

作者： GUIllAUME MARCAUD SAMUEl SERNA KARAMANIS PANAGHIOTIS CARlOS AlONSO-RAMOS XAVIER lE ROUX MATHIAS BERCIANO THOMAS MAROUTIAN GUIllAUME AGNUS PASCAl AUBERT ARNAUD JOllIVet AlICIA RUIZ-CARIDAD lUDOVIC lARGEAU NATHAlIE ISAC ERIC CASSAN SYlVIA MATZEN NICOlAS DUBREUIl MICHEl RERAT PHIlIPPE lECOEUR lAURENT VIVIEN Centre de Nanosciences et Nanotechnologies(C2N) Université-Paris-SudCNRS UMR 9001Universite Paris-SaclayOrsay 91405France Department of Materials science and Engineering Massachusetts Institute of TechnologyCambridgeMasschusetts 02139USA Department of Physics Bridgewater State UniversityBridgewaterMassachusetts 02325USA institut des sciences analytiques et de physico-chimie pour l’environnement et les Matériaux CNRSUniversite de Pau et des Pays de l’Adour64053 Pau CedexFrance laboratoire Charles Fabry Institut d’Optique Graduate SchoolCNRSUniversitéParis-Saclay91127 Palaiseau CedexFrance lP2N Institut d’Optique Graduate SchoolCNRSUniv.Bordeaux33400 TalenceFrance

Nonlinear all-optical technology is an ultimate route for the next-generation ultrafast signal processing of optical communication *** nonlinear functionalities need to be implemented in photonics,and complex oxides are considered as promising candidates due to their wide panel of *** this context,yttria-stabilized zirconia(YSZ)stands out,thanks to its ability to be epitaxially grown on silicon,adapting the lattice for the crystalline oxide family of *** report,for the first time to the best of our knowledge,a detailed theoretical and experimental study about the third-order nonlinear susceptibility in crystalline *** self-phase modulation-induced broadening and considering the in-plane orientation of YSZ,we experimentally obtained an effective Kerr coefficient of n2YSZ=4.0±2×10^-19 m^2·W^-1 in an 8%(mole fraction)YSZ *** agreement with the theoretically predicted n2YSZ=1.3×10^-19 m^2·W^-1,the third-order nonlinear coefficient of YSZ is comparable with the one of silicon nitride,which is already being used in nonlinear *** promising results are a new step toward the implementation of functional oxides for nonlinear optical applications.

关键词： materials. nonlinear crystalline

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Role of the floodplain lakes in the methylmercury distribution and exchanges with the Amazon River,Brazil

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Journal of Environmental sciences 2018年第6期30卷 24-40页

作者： Poliana Dutra Maia laurence Maurice Emmanuel Tessier David Amouroux Daniel Cossa Patricia Moreira-Turcq Henri etcheber Universidade de Brasilia-Faculdade UnB Planaltina Area Universitaria n. 1-Vila Nossa Senhora de Fatima Planaltina 73300-000 Brasilia DF Brazil Geosciences environnement Toulouse (Get) Observatoire Midi Pyrenees Universite de Toulouse CNRS IRD14 Avenue Edouard Belin F-32400 Toulouse France CNRS/Univ Pau & Pays Adour Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Materiaux UMR5254 F-64000 Pau Prance Universite Grenoble Alpes CP 40700 F-38058 Grenoble Cedex 9 France EPOC UMR 5805 Universite de Bordeaux I Av. des Facultes F-33405 Talence France

Seasonal variability of dissolved and particulate methylmercury（F-MeHg, P-MeHg） concentrations was studied in the waters of the Amazon River and its associated Curuai floodplain during hydrological year 2005–2006, to understand the MeHg exchanges between these aquatic systems. In the oxic white water lakes, with neutral pH, high F-MeHg and P-MeHg concentrations were measured during the rising water stage（0.70 ± 0.37 pmol/l, n = 26） and flood peak（14.19 ± 9.32 pmol/g, n = 7） respectively, when the Amazon River water discharge into the lakes was at its maximum. The lowest mean values were reported during the dry season（0.18 ± 0.07 pmol/l F-MeHg, n = 10 and 1.35 ± 1.24 pmol/g P-MeHg, n = 8）, when water and suspended sediments were outflowing from the lakes into the River. In these lakes,the MeHg concentrations were associated to the aluminium and organic carbon/nitrogen changes. In the black water lakes, with acidic pH and reducing conditions, elevated MeHg concentrations were recorded（0.58 ± 0.32 pmol/l F-MeHg, n = 16 and 19.82 ± 15.13 pmol/g PMeHg, n = 6）, and correlated with the organic carbon and manganese concentrations. Elevated values of MeHg partition coefficient（4.87 〈 Kd〈 5.08 log（l/kg） indicate that MeHg is mainly transported associated with the particulate phase. The P-MeHg enrichment detected in all lakes suggests autochthonous MeHg inputs from the sediments into the water column. The MeHg mass balance showed that the Curuai floodplain is not the source of P-MeHg for the Amazon River.

关键词： Methylmercury Water Sediment Amazon River Floodplain lakes

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N-Methylcarbamoyl Azide:Spectroscopy,X-ray Structure and Decomposition via Methylcarbamoyl Nitrene

N-Methylcarbamoyl Azide:Spectroscopy,X-ray Structure and Dec...

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第十五届全国化学动力学会议

作者：万华斌 Manabu Abe Didier Bégue Xiaoqing Zeng College of Chemistry Chemical Engineering and Materials ScienceSoochow University Department of Chemistry Graduate School of ScienceHiroshima University institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux(IPREM) Universite de Pau et des Pays de l'Adour

N-Methylcarbamoyl azide Me(H)NC(O)N

关键词： azides nitrenes matrix-isolation X-ray crystallography photochemistry

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long term survival and limited migration of genetically modified monocytes/macrophages grafted into the mouse brain

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Journal of Biomedical science and Engineering 2013年第5期6卷 561-571页

作者： Chamsy Sarkis Gabriel Gras Francoise Sanchez Jacques Mallet Che Serguera Centre de Recherche de l’institut du Cerveau et de la Moelle Epiniere Equipe de Biotechnologie et BiothérapieHopital Pitié-SalpetriereParisFrance CEA Institute of Emerging Diseases and Innovative TherapiesDivision of Immuno-VirologyUMR E1 CEA and University Paris SouthFontenay-aux RosesFrance Centre d’etudes d’Agents Pathogenes et Biotechnologies pour la Sante(CPBS) UMR 5236MontpellierFrance laboratoire de Modélisation des Biotherapies Groupe INSERM U986MIRCenCEAFontenay-aux-RosesFrance

In mammals, myeloid progenitors infiltrate the developing central nervous system (CNS), through the immature blood-brain barrier (BBB), the ventricular layer or the pial surface migrate and give rise to resident microglia. In the mature brain, however, the BBB hampers such recruitment from the blood-stream and long-term establishment of blood borne myeloid cells in the CNS thus appears at best limited. Hematopoietic stem cell-derived microglia, nevertheless, represents a promising tool for the correction of genetic deficits in the brain. We thus investigated the fate of primary human monocytes, and monocyte-derived macrophages, following transplantation into the adult mouse brain overpassing the BBB. Furthermore, we documented the ability of such cells to deliver a lysosomal enzyme into the brain following genetic modification with a recombinant adenoviral vector carrying the human β-glucuronidase cDNA. When implanted into the mouse striatum, the engineered primary cells survived and expressed the transgene for as much as 8 months. Moreover, the donor cells could migrate out of the grafting site and settle along blood vessels or myelin tracts although at limited distance. Migrating donor cells down-regulated the expression of CD14 andHlA DR, suggesting the adoption of a deactivated microglia-like phenotype. Our observations establish the ability of circulating mononuclear phagocytes to integrate into the brain after transplantation and express a transgene on the long term. These cells might thus be employed for autologous transplantation for the delivery of secreted therapeutic proteins in the context of a wide range of brain affections.

关键词： Adenoviral Vector Human Myeloid Cells β-Glucuronidase Ex Vivo Gene Therapy Neurotransplantation

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Knowledge of Healthcare Workers Regarding Dengue and Chikungunya in Some Health Facilities of the City of Yaoundé(Cameroon) and Its Neighbourhood

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Open Journal of Clinical Diagnostics 2021年第3期11卷 77-91页

作者： Stella Mariette Nana-Ndjangwo Ruth Mony Roland Bamou Gaël Bekono Ango’o Daina Paola Wantou Tchangou Parfait Awono-Ambene Charles Félix Bilong Bilong Christophe Antonio-Nkondjio laboratory of Parasitology and Ecology Faculty of Science University of Yaoundé Yaoundé Cameroon institut de Recherche de Yaoundé (IRY) Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC) Yaoundé Cameroon Vector Borne Diseases laboratory of the Applied Biology and Ecology Research Unit (VBID-URBEA) Ecole des sciences de la Santé Université Catholique d’Afrique Centrale Yaoundé Cameroun institut Supérieur des sciences et Techniques Appliquées à la Santé Yaoundé Cameroun Vector Biology liverpool School of Tropical Medicine Pembroke Place Liverpool UK

Background: Good knowledge of diseases’ epidemiology, diagnostic methods and treatment schemes are critical for early detection and effective management of dengue and chikungunya outbreaks. Here, we assessed knowledge and practices regarding dengue and chikungunya among health care workers of some health facilities of Yaoundé and its surroundings. Methods: A descriptive cross-sectional study was conducted from January to August 2020 in 35 health facilities of Yaoundé and its surroundings. Structured pre-tested questionnaire including 11 questions was used to assess healthcare workers’ (i) knowledge on dengue and chikungunya (pathogen, mode of transmission, signs and symptoms) and, (ii) management practices (diagnosis, prevention and treatment measures). Face to face interviews were conducted with healthcare workers including medical doctors, nurses, medical assistants and laboratory assistants. Findings: A total of 232 healthcare workers were interviewed. despite that 40.95% (n = 95) of respondents had heard about dengue and chikungunya, only 4.74% (n = 11) of them were aware of the fact that both diseases are caused by virus. Also, 9 out of 232 (3.88%) knew that these diseases were transmitted by the bite of an Aedes mosquito. About 15.52% (n = 36) were able to give at least 1 clinical symptom related to dengue and chikungunya. The main diagnostic method they knew was Polymerase Chain Reaction (3.02%;n = 7). For prevention, many participants indicated vector control by using insecticide treated bednets or destroying potential breeding sites (14.23%;n = 33). Only few participants 3.88% (n = 9) knew how to manage dengue or chikungunya cases. To improve the management of both diseases, a significant proportion of healthcare workers (37.93%;n = 88) reported being in need of additional training. Conclusion: The poor knowledge regarding dengue and chikungunya among healthcare workers in Yaoundé and its neighbourhood raises the need to intensif

关键词： Dengue Chikungunya Healthcare Workers Knowledge Management Practic-es

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UN PROBlEME D’UNICITE RElATIF AUX FONCTIONS MEROMORPHES

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science in China,Ser.A 1963年第6期 743-750页

作者：熊庆来 institut de Mathematiques Academia Sinica

Soit f（z） une fonction,mromorphe dans tout le *** par E（a）l’ensemble des points-a de f（z） et par （Eλ）（a） celui des points de E（a） dont lesordres de multiplicit ne dpassent pas un certain entier λ;l’ensemble compl-mentaire de Eλ)（a） par raport E（a） aura Eλ（a） pour *** allonsdonner dans la prsente Note quelques rsultats concernant la dtermination def（z） par certains ensembles Eλ（a）.*** respectivement par Nλ)（r,a） et N)（λ（r,a） les indices dedensit constitus par tes points de Eλ）（a） et ceux de E(λ（a） qui sont compris dansle cercle |z|≤*** seconde ingalit fondamentale de Nevanlinna [1] peuts’crire

关键词： notation compl ensemble indices Premier borne resto forme termination premier

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SUR lA STABIlISATION DE lA VIBRATION lASTIQUE (Ⅲ)

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science China Mathematics 1976年第3期 323-346页

作者：王康宁关肇直 Academia Sinica institut de Mathématiques

On considère dans ce mémoiro le problème de la commande de la vibration élastique d’un vehiule spatial à corps mince oǜ l’on emploie eommo rétroaction la vitesse angulaire, le déplacement angulaire et l’accélération linéaire mesurés par los instruments montés sur le véhicule. On va élaborer ici une boucle de commando pour réaliser la stabilisation du système à boucle formée formé par le couplage du système de la vibration élastique du véhicule st du régulateur en utilisant la force fournie par le gouvernail du véhieule. On prend comme modèle la poutre élastique à deux oxtrémités libres pour déerire la vibration élastique du véhieule, et on en obtient à l’aide de la théorio de la perturbation des opérateurs linéaires les conditions pour la stabilisation du système de la vibration élastique du véhicule muni d’un régulateur par la rétroaction de la vitesse angulaire, du déplacement angulaire et de l’accélération linéaire.

关键词： der SUR lA STABIlISATION DE lA VIBRATION lASTIQUE DE

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