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Determination of Lead in Water by Linear Sweep Anodic Stripping Voltammetry (LSASV) at Unmodified Carbon Paste electrode: Optimization of Operating Parameters

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American Journal of Analytical Chemistry 2018年第3期9卷 171-186页

作者： Ndoye Mouhamed Kane Cheikhou Gadji elhadji Momar Rokhy Diédhiou Moussa Bagha Mar-Diop Codou Guèye Theo Tzedakis ecole Supérieure Polytechnique Université Cheikh Anta Diop Dakar Senegal Laboratoire de Génie Chimique UMR CNRS 5503 Université de Toulouse III-Paul Sabatier Toulouse France

This study presents the elaboration of a simple and cheap electrode made by carbon paste introduced into a cavity of electrode body, and used for the lead traces determination in tap water. A potentiostatic pre-electrolysis at constant voltage enables the reduction of the lead (Pb2+) and the accumulation of the metallic lead at and into the carbon paste;the reoxidation of the Pb (Linear sweep voltammetry) leads to the anodic striping peak. The effect of the main operating parameters on the shape of the peak and the magnitude of the current was examined and their optimal values were determined. Then calibration was achieved and the method was successfully applied (using all the optimized parameters) to the determination of lead in water, with a detection limit of 0.138 μg·L-1. Compared to other methods (ICP-AeS for example), the proposed method offers a satisfactory detection limit of the Pb2+ (0.138 μg·L-1) because of the important specific area of the carbon paste electrode, for a significantly lower cost. Besides, there is no observed loss in the electrode answer in terms of peak current, which means that there is no any irreversible steps nor deactivation of the electrode, even after ten successive measurements;only reduction of the lead followed by the deposit oxidation was observed at the electrode.

关键词： Carbon Paste electrode Lead Linear Sweep Anodic Stripping Voltammetry Water

Geochemistry of Magmatic Rocks of the Syama Belt, Southern Mali, West African Craton

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Open Journal of Geology 2022年第3期12卷 250-272页

作者： Dasso Yollande Traoré Seko Sanogo Adama Youssouf Koné Ismaïla N’Diaye Mamadou Lamine Bouaré Didier Béziat Laboratoire de Cartographie DER de Géologie Faculté des Sciences et Techniques (FST) Université des Sciences des Techniques et des Technologies de Bamako (USTTB) Bamako Mali Laboratoire de Minéralogie et de Pétrologie DER de Géologie Faculté des Sciences et Techniques Université des Sciences des Techniques et des Technologies de Bamako Bamako Mali ecole Nationale d’Ingénieurs Abdramane Baba Touré (eNI-ABT) Bamako Mali université paul sabatier de Toulouse Toulouse France

Within southern Mali, the Syama belt constitutes a linear major structure-oriented N-S, which host several gold deposits (e.g., Syama and Tabakoroni) and prospect areas (e.g. Tellem). The Syama Belt is formed by magmatic rocks (basalts, lamprophyres, andesites, dacites and microgranites);sedimentary rocks (shales) and volcano-sedimentary rocks (pyroclastics). The magmatic rocks are divided into two main volcanic series: tholeiitic affinity rocks (basalts and lamprophyres) and calc-alkaline affinity (andesites) that are the most evolved. The field relationships between rocks of these two series suggest that the calc-alkaline series are younger the tholeiitic series. These tholeiitic series present the Mid-Ocean Ridge Basalt (MORB) affinity whereas the calc-alkaline series would be linked to an island arc-type. This coexistence is not an isolated case within the West African Craton (WAC). Otherwise, the Syama belt has all the characteristics of other belts, within which a number of gold deposits are developed, in the WAC.

关键词： Syama Belt Magmatic Rocks MORB Boualé-Mossi Domain Southern Mali West African Craton (WAC)

Laboratory scale study of an industrial phosphate and thermal treatment for polluted dredged sediments

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International Journal of Sediment Research 2012年第4期27卷 538-546页

作者： Souhila KRIBI Jocelyn RAMAROSON Ange NZIHOU Patrick SHARROCK Guy DePeLSeNAIRe ecole des Mines d'Albi-Carmaux RAPSODEE UMR-CNRS 2392Route de Teillet-81013 ALBI CT Cedex 09France Ph.D. paul sabatier university Solvay DCRTRue de Ransbeek 310BrusselsBelgium

Dredged sediments are being chemically treated with phosphoric acid on an industrial *** effectiveness of the treatment was evaluated by performing the chemical reaction in a tubular reactor, followed by convective drying and maturation of the treated sediment at ambient temperature and finally thermal destruction of the organic matter by calcinations(500℃-900℃).The influence of acid concentration and calcination temperature on the specific surface area of the sediment was investigated. The stabilization of the heavy metals was evaluated by leaching tests and sequential extraction *** phosphoric acid treatment is effective in reducing heavy metal mobility,a prerequisite for recycling the sediments in various construction materials.

关键词： Dredged sediments Heavy metal pollution Chemical treatment Thermal treatment

Livestock induces strong spatial heterogeneity of soil CO2, N2O and CH4 emissions within a semi-arid sylvo-pastoral landscape in West Africa

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Journal of Arid Land 2017年第2期9卷 210-221页

作者： Mohamed H ASSOUMA Dominique SeRCA Frederic GUeRIN Vincent BLANFORT Philippe LeCOMTe Ibra TOURe Alexandre ICKOWICZ Raphael J MANLAY Martial BeRNOU Jonathan VAYSSIeReS CIRAD-UMR Selmet Campus International Baillarguet Montpellier 34398 France DP PPZS ISRA-LNERV BP 2057 Dakar Hann Senegal Laboratoire d'Aerologie-OMP Universite Paul Sabatier 14 Avenue Edouard Belin Toulouse 31400 France Geosciences environnement Toulouse UMR 5563 & UR 234 IRD Universite Paul Sabatier Avenue Edouard Belin 14 Toulouse 31400 France CILSS 03 BP 7049 Ouagadougou Burkina Faso AgroParisTech-UMR eco&Sols 2 place Viala Montpellier SupAgro Montpellier 34060 France IRD-UMR eco&Sols 2 place Viala Montpellier SupAgro Montpellier 34060 France

Greenhouse gas （GHG） emissions from the surface soils and surface water receiving animal excreta may be important components of the GHG balance of terrestrial ecosystems, but the associated processes are poorly documented in tropical environments, especially in tropical arid and semi-arid areas. A typical sylvo-pastoral landscape in the semi-arid zone of Senegal, West Africa, was investigated in this study. The study area （706 km2 of managed pastoral land） was a circular zone with a radius of 15 km centered on a borehole used to water livestock. The landscape supports a stocking rate ranging from 0.11 to 0.39 tropical livestock units per hectare depending on the seasonal movements of the livestock. Six landscape units were investigated （land in the vicinity of the borehole, natural ponds, natural rangelands, forest plantations, settlements, and enclosed plots）. Carbon dioxide （CO2）, nitrous oxide （N2O） and methane （CH4） fluxes were measured with static chambers set up at 13 sites covering the six landscape units, and the 13 sites are assumed to be representative of the spatial heterogeneity of the emissions. A total of 216 fluxes were measured during the one-year study period （May 2014 to April 2015）. At the landscape level, soils and surface water emitted an average 19.8 t C-CO2 eq/（hm2.a）（CO2： 82%, N2O： 15%, and CH4： 3%）, but detailed results revealed notable spatial heterogeneity of GHG emissions. CO2 fluxes ranged from 1148.2 （±91.6） mg/（m2.d） in rangelands to 97,980.2 （±4,861.7） mg/（m2.d） in surface water in the vicinity of the borehole. N2O fluxes ranged from 0.6 （±0.1） mg/（m2.d） in forest plantations to 22.6 （±10.8） mg/（m2.d） in the vicinity of the borehole. CH4 fluxes ranged from -3.2 （±0.3） mg/（m2.d） in forest plantations to 8788.5 （±2295.9） mg/（m2.d） from surface water in the vicinity of the borehole. This study identified GHG emission ＂hot spots＂ in the landscape. emissions from the surface soils were significantly higher in the landscape units most freq

关键词： greenhouse gases soil surface water livestock landscape Senegal

Genomic Analysis Reveals a Cryptic Pangolin Species

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Genomic Analysis Reveals a Cryptic Pangolin Species

第十六届全国野生动物生态与资源保护学术研讨会

作者： Tong-Tong Gu Hong Wu Feng Yang Philippe Gaubert Sean P. Heighton Ye-Yi-Zhou Fu Ke Liu Shu-Jin Luo Hua-Rong Zhang Jing-Yang Hu Li Yu State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan School of Life Sciences Yunnan University Kadoorie Farm and Botanic Garden Laboratoire evolution et Diversité Biologique CNRS/UPS/IRD Université Toulouse III - Paul Sabatier Centro Interdisciplinar de Investiga??o Marinha e Ambiental Universidade do Porto Terminal de Cruzeiros do Porto de Leix?es The State Key Laboratory of Protein and Plant Gene Research School of Life Sciences

eight extant species of pangolins are currently recognized. Recent studies found that two mitochondrial haplotypes identified in confiscations in Hong Kong could not be assigned to any known pangolin species, implying the existence of a previously unrecognized species. Here, we report that two additional mitochondrial haplotypes identified in independent confiscations from Yunnan align to the potential new species haplotypes, supporting the existence of this mysterious species/population. To verify the new species scenario, we performed a comprehensive analysis of scale characteristics and 138 whole genomes representing all recognized pangolin species and the cryptic new species, 98 of which were generated here. Our morphometric results clearly attributed this cryptic species to Asian pangolins(Manis sp.), and the genomic data provide robust and compelling evidence that it is a pangolin species distinct from those recognized previously, which separated from Philippine pangolin and Malayan pangolin over five million years ago. Our study provides a solid genomic basis for its formal recognition as the ninth pangolin species and the fifth Asian one, supporting a new taxonomic classification of pangolins. The effects of glacial climate changes and recent human activities driven by illegal trade are inferred to have caused its population decline with the genomic signatures showing low genetic diversity, a high level of inbreeding, and high genetic load. Our discovery greatly expands current knowledge of pangolin diversity and evolution, and has vital implications for conservation efforts to prevent the extinction of this enigmatic and endangered species from the wild.

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MicroRNAs as emerging biomarkers and therapeutic targets for pancreatic cancer

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World Journal of Gastroenterology 2014年第32期20卷 11199-11209页

作者： Marion Gayral Sébastien Jo Naima Hanoun Alix Vignolle-Vidoni Hubert Lulka Yannick Delpu Aline Meulle Marlène Dufresne Marine Humeau Maёl Chalret du Rieu Barbara Bournet Janick Sèlves Rosine Guimbaud Nicolas Carrère Louis Buscail Jérome Torrisani Pierre Cordelier Cancer Research Center of Toulouse Team 10 UMR INSERM U1037Université Paul Sabatier P?le Digestif Centre Hospitalier Universitaire Toulouse

Despite tremendous efforts from scientists and clinicians worldwide, pancreatic adenocarcinoma(PDAC) remains a deadly disease due to the lack of early diagnostic tools and reliable therapeutic approaches. Consequently, a majority of patients(80%) display an advanced disease that results in a low resection rate leading to an overall median survival of less than 6 months. Accordingly, robust markers for the early diagnosis and prognosis of pancreatic cancer, or markers indicative of survival and/or metastatic disease are des-perately needed to help alleviate the dismal prognosis of this cancer. In addition, the discovery of new therapeutic targets is mandatory to design effective treatments. In this review, we will highlight the translational studies demonstrating that microRNAs may soon translate into clinical applications as long-awaited screening tools and therapeutic targets for PDAC.

关键词： MicroRNAs Biomarkers Pancreatic cancer Therapeutic

S1P: the elixir of life for naive T cells

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Cellular & Molecular Immunology 2018年第7期15卷 657-659页

作者： Michaël Pérès Anne Montfort Nathalie Andrieu-Abadie Céline Colacios Bruno Ségui INSeRM UMR1037 Centre de Recherches en Cancérologie de ToulouseToulouse 31037France Facultéde pharmacie UniversitéToulouse III Paul-SabatierToulouse 31062France Laboratoire d’hématologie CHU de ToulouseToulouse 31059France equipe Labellisée Ligue Contre Le Cancer Toulouse 31037France Correspondence:Professor B SéguiPhDINSERMUMR1037 CRCTCentre de Recherches en Cancérologie de Toulouse2 avenue Hubert CurienToulouse 31037France

During their life,T cells are constantly circulating throughout the ***-1-phosphate(S1P),a sphingolipid metabolite,triggers T cell egress from the thymus and secondary lymphoid organs(SLO)into the lymph and the *** phenomenon is dependent on the S1P gradient between lymphoid organs(including thymus and SLO)and the lymphatic and blood vessels,which exhibit low,intermediate and high S1P levels,respectively.T cells follow the S1P gradient via the engagement of the G-protein-coupled receptor S1P receptor 1(S1P1)expressed on T cells.1 S1P production is regulated by various sphingolipid-metabolizing *** sphingosine kinases 1 and 2(SKs),encoded by Sphk1 and Sphk2,phosphorylate the sphingosine(Sph)into ***,S1P can be dephosphorylated to Sph by S1P phosphatases 1 and 2,encoded by Sgpp1 and ***,S1P can be irreversibly degraded by the S1P Lyase(SPL),encoded by Sgpl1,into phosphoethanolamine and hexadecenal.

关键词： organs al. lymphoid

Mixed H2/H∞ control via nonsmooth optimization

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Mixed H2/H∞ control via nonsmooth optimization

Joint 48th Ieee Conference on Decision and Control and 28th Chinese Control Conference

作者： Pierre Apkarian Dominikus Noll Aude Rondepierre ONeRA-2 université paul sabatier Institut de Mathématiques the Institut National des Sciences Appliquées Institut de Mathématiques

We present a new approach to mixed H/H output feedback control synthesis. Our method uses nonsmooth mathematical programming techniques to compute locally optimal H/H-controllers, which may have a predefined structure... 详细信息

关键词： H2/H∞ synthesis multi-objective control robustness and performance nonsmooth optimization bundle methods

Grigg-Skjellerup彗星磁场和电子的数据分析

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Grigg-Skjellerup彗星磁场和电子的数据分析

1997年中国地球物理学会第十三届学术年会

作者：曹晋滨 C．Mazelle Henri．Reme 中国科学院空间科学与应用研究中心 universite paul sabatier ToulouseFrance universite paul sabatier ToulouseFrance

＜正＞当太阳风通过行星际空间时,它和它所碰到的星体的相互作用显示出很强的多样性。彗星和太阳风的相互作用是其中最引人注目的现象之一,它极大地丰富了空间等离子体物理学研究。欧洲空间局Giotto飞船在1986年观测哈雷彗星之后,在1992...

＜正＞当太阳风通过行星际空间时,它和它所碰到的星体的相互作用显示出很强的多样性。彗星和太阳风的相互作用是其中最引人注目的现象之一,它极大地丰富了空间等离子体物理学研究。欧洲空间局Giotto飞船在1986年观测哈雷彗星之后,在1992年7月10日又对Grigg-Skjellerup彗星成功地进行了近核探测。整个探测过程从1992年7月10日0257 UT一直到2345UT。飞船距彗星最近距离约为200

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