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Lamprophyre Rocks in the Nassara gold Deposit, Southwest Burkina Faso: Characteristics and Implication for Mining Exploration

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Open Journal of geology 2023年第12期13卷 1291-1311页

作者： Pascal Ouiya Adama Ouédraogo Yaméogo Sâga Sawadogo Séta Naba Ecole Normale Supérieure (ENS) Institut Sciences et Technologie (IST) Ouagadougou Burkina Faso Laboratoire géosciences et Environnement (LagE) Earth Sciences Department Ouagadougou Burkina Faso University Norbert ZONgO (UNZ) Koudougou Burkina Faso

The lamprophyres are late dykes that cut the formations hosting the gold mineralization in the Nassara deposit. They are geographically and spatially related to most orogenic gold deposits. It is with the aim of characterizing them and seeing their implications for exploration that this work is carried out. To achieve our objective, petrographic studies and chemical analyses of minerals (pyroxenes, amphiboles, feldspars, chromite) and geochemical analyses of total rock were carried out. These studies have enabled us to classify the Nassara lamprophyres as calc-alkaline lamprophyres of the spessartite type. The Cr, Co, Ni and Mg enrichment of these rocks would indicate a depleted mantle source, with LILE enrichment by fluids probably related to metasomatic activity. The various diagrams show that they are depleted in HREE and enriched in LREE. The high Nb/Ta ratios in our data indicate metasomatic activity probably linked to amphibole and rutile in the mantle prior to melting. The geodynamic context of spessartite-type lamprophyres indicates a signature linked to late-orogenic to post-collisional subduction. They are late-orogenic to post-collisional lamprophyres enriched in compatible elements (Cr, Ni, Co) and display a negative Ta-Nb-Ti (TNT) anomaly. The frequent association of these lamprophyre dykes with the deposits does not indicate the source of the gold for these deposits, but rather zones of crustal permeability capable of draining hydrothermal fluids at the time of emplacement. good mapping of lamprophyre dykes, especially in shear zones, could therefore guide prospecting and identify potential zones of hydrothermal fluid circulation.

关键词： Nassara Calc-Alkaline Lamprophyre Metasomatic Activity LILE HREE LREE

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Solar Photocatalysis of TiO₂ Supported Natural Palygorskite Nanofibers Elaborated by a One_Pot Mechanochemical Route

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Journal of Minerals and Materials Characterization and Engineering 2022年第3期10卷 254-274页

作者： Lakbita Omar Rhouta Benaissa goetz Vincent Maury Francis Plantard gaël Daoudi Lahcen Mohammed VI Polytechnic University (UM6P) Marrakech Morocco IMED_Lab Faculty of Sciences and Technologies Cadi Ayyad University Marrakech Morocco PROcédés Matériaux et Energie Solaire Rambla de la Thermodynamique PROMES_CNRS UPR 8521 Perpignan France CIRIMAT Université de Toulouse Toulouse France Laboratoire de geoscience et géoenvironnement Faculté des Sciences et Techniques Guéliz Université Cadi Ayyad Marrakech Morocco

This study reports the successful synthesis of supported TiO2_Palygorskite nanocomposites by a one-pot dry mechanochemical route. Indeed, the elaboration procedure involved an in-situ reaction between accessories carbonates present in raw fibrous palygorskite clay and titanyl sulfate (TiOSO4) precursor under variable grinding conditions, essentially ball/solid matter mass ratio and rotation velocity. This yielded after air annealing at 600%C for 1 h to the immobilization of anatase TiO2 nanoparticles (≈8 nm of average size) as evidenced by XRD and TEM analyses. Once the conditions of elaboration were optimized, the photocatalytic properties were evaluated under 3 conditions: artificial UV radiation, artificial solar radiation (UV + visible range) and under dynamic solar illumination taking into account the discontinuities of the solar resource. The results allowed the estimation and comparison of the catalyst’s capabilities and showed its ability to work under natural irradiation. The so developed supported photocatalysts TiO2/Palygorskite exhibited a good activity towards the removal of Orange g (Og) dye from aqueous media under artificial UV and natural solar radiations.

关键词： TiO2 Palygorskite Mechanochemical Synthesis Nanocomposite Solar Photocatalysis Wastewater Treatment

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Identification of groundwater Potential Zones in Samendeni Watershed in Sedimentary and Semi-Arid Contexts of Burkina Faso, Using Analytic Hierarchy Process (AHP) Method and gIS

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American Journal of Climate Change 2023年第1期12卷 172-203页

作者： Sadraki Yabre Youssouf Koussoubé Sauret Élie Serge gaëtan Nicaise Yalo Stephen Silliman West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL) Doctoral Research Program in Climate Change and Water Resources Institut National de l’eau Université d’Abomey Calavi Cotonou Bénin Laboratoire géosciences et Environnement (LagE) Département des Sciences de la Terre Université Joseph KI-ZERBO/Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Ouagadougou Burkina Faso Centre National de Recherche Scientifique et Technologique Institut de l’Environnement et de Recherches Agricoles-Département Gestion des Ressources Naturelles/Systèmes de Productions DRREA-Ouest Station de Farako-ba Bobo-Dioulasso Burkina Faso Laboratoire d’Hydrologie Appliquée (LHA) Institut National de l’eau Université d’Abomey Calavi Cotonou Bénin School of Science Technology Engineering and Math Trevecca Nazarene University Nashville Tennessee USA

Demand for water increases in Samendeni regarding the undertaken agricultural projects while pressure on surface water from global warming/evapotranspiration also increases. Thus, the need to evaluate the groundwater potential in the catchment is crucial as alternative supplier of water and resilience to climate hazards. The AHP was performed integrating ten influencing factors such as geomorphology, geology, soil, land use/land cover (lulc), slope, rainfall, drainage density, borehole rate & depth and piezometric level to generate groundwater potential zones (gWPZs) in Samendeni watershed (4420 km2). All the factors were processed and ranged into five (5) classes. Weight was assigned to each class of thematic layer. These thematic layers were then reclassified based on the normalized weight to be used in the calculation of groundwater potential zones (gWPZ). The final output, groundwater potential map, revealed a significant groundwater potential with very good (11%), good (31%), moderate (30%), poor (20%), and very poor (8%) of proportion. The interesting (very good, good) gWPZs in the study area are mostly in the central towards the east. The poor zones in term of groundwater potential are concentrated in the upper west region of the watershed. Besides the cross-validation with the relationship between different groundwater potential zones and the wells available in the study area, the overall accuracy was estimated to 88% provided from the result of the similarity analysis where 22 out of the 25 validation wells match with the expected yield classes of gWPZs. The statistics from that validation revealed the performance of AHP method to delineate groundwater potential zones at catchment level.

关键词： Climate Change Resilience groundwater Potential Water Management Conjunctive Use AHP gIS Samendeni Watershed

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The status of Nrf2-based therapeutics： current perspectives and future prospects

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Neural Regeneration Research 2016年第11期11卷 1708-1711页

作者： Irina g. gazaryan Bobby Thomas Department of Cell Biology and Anatomy School of Medicine New York Medical College Valhalla NY USA Department of Chemistry and Physical Sciences Dyson College Pace University Pleasantville NY USA Departments of Pharmacology Toxicology and Neurology Medical College of Georgia Augusta University Augusta GA USA

This mini-review presents the authors＇ vision on the current status and future trends in the development of neuroprotective agents working via activation of nuclear factor erythroid 2-related factor 2 （Nrf2）, and in particular, via disruption of Nrf2-Keap 1 interaction. There are two opposite ＂chemical＂ mechanisms underlying such activation： the first one is a non-specific covalent modification of Keapl thiols, resulting in side effects of varied severity, and the second one is the shift of the Nrf2-Kelch-like ECH associated protein-1 （Keapl） binding equilibrium in the presence of a competitive and chemically benign displacement agent. At this point, no displacement activators exhibit sufficient biological activity in comparison with common Nrf2 activators working via Keapl thiol modification. hence, the hope in therapeutics is now linked to the FDA approved dimethylfumarate, whose derivative, monomethylfumarate, as we demonstrated recently, is much less toxic but equally biologically potent and an ideal candidate for clinical trials right now. A newly emerging player is a nuclear inhibitor of Nrf2, BTB domain and CNC homolog 1 （Bach1）. The commercially developed Bachl inhibitors are currently under investigation in our laboratory showing promising results. In our viewpoint, the perfect future drug will present the combination of a displacement activator and Bach 1 inhibitor to insure safety and efficiency of Nrf2 activation.

关键词： Nrf2 Keap l Bach l electrophiles oxidative stress antioxidants

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Complexity of the NWA 773 Clan: New Evidence from Lunar Olivine gabbro NWA 6950

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Journal of Earth Science 2023年

作者： Qi he Long Xiao Ioannis Baziotis Xiaochao Che Yuqi Qian Jiawei Zhao Beijing SHRIMP Center， Institute of geology， Chinese Academy of geological Sciences Planetary Science Institute， School of Earth Sciences， China University of geosciences 2. Laboratory of Mineralogy and geology， Agricultural University of Athens

NWA 6950 is a type of cumulate gabbro meteorite that displays features indicating a lunar origin. Specifically， the Fe/Mn values of olivines and pyroxenes in the meteorite suggest a lunar origin， as does the presence of Fe-Ni metal. The meteorite has also undergone intense shock metamorphism， which is evidenced by the presence of ringwoodite， tuite， and xieite (a type of chromite with a CaTi2O4structure) within the shock melt veins (SMVs).The texture， mineral modal abundances， and bulk compositions (measured from the SMVs) of NWA 6950 are similar to those of the NWA 773 clan， as are the concentrations and patterns of rare-earth-elements in olivine， pyroxene， plagioclase， and phosphate. In-situ U-Pb dating of baddeleyite and phosphate in NWA 6950 has determined its crystallization age to be 3 133 ± 11 Ma and 3 129 ± 23 Ma， which is consistent with age data provided by Shaulis et al. (2017).Further， the chronology of the NWA 773 clan appears to be at least bimodal when considering the age of NWA 3333 (3 038 ± 20 Ma; Merle et al.， 2020). The tight range of ages for the NWA 773 clan at approximately 3.1 ga coincides with a change in the eruption flux and style on the Moon. This suggests that lunar volcanism may have shifted from extrusive-dominated to intrusive-dominated at approximately 3.1 ga， resulting in the widespread distribution of gabbro lithologies on the Moon.

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A Model to Describe the Fracture of Porous Polygranular graphite Subject to Neutron Damage and Radiolytic Oxidation

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Computers, Materials & Continua 2016年第3期51卷 163-185页

作者： g.Smith E.Schlangen P.E.J.Flewitt A.g.Crocker A.Hodgkins Interface Analysis Centre School of PhysicsUniversity of BristolBristolBS81TLUK Faculty of Civil Engineering and geosciences Delft University of TechnologyDelftNetherlands HH Wills Physics Laboratory School of PhysicsUniversity of BristolBristolBS81TLUK Physics Department University of SurreyGuildfordGU27XH AMEC Clean Energy now AMEC Foster-WheelerWalton House404 Faraday StreetBirchwood ParkWarringtonCheshireWA36GAUK

Two linked models have been developed to explore the relationship between the amount of porosity arising in service from both radiolytic oxidation and fast neutron damage that influences both the strength and the force-displacement(load-displacement)behaviour and crack propagation in pile grade A graphite used as a nuclear reactor moderator *** models of the microstructure of the porous graphite for both unirradiated and irradiated graphite are *** form the input for the second stage,simulating fracture in lattice-type finite element models,which predicts force(load)-displacement and crack propagation *** comprising aligned filler particles,typical of needle coke,in a porous matrix have been *** purpose was to isolate the contributions of filler particles and porosity to fracture strength and crack paths and consider their implications for the overall failure of reactor core graphite.

关键词： Reactor core graphite Modelling microstructure FE lattice model Fracture strength Crack path

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Construction of an Energy-Efficient Detour Non-Split Dominating Set in WSN

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Computers, Materials & Continua 2022年第10期73卷 689-700页

作者： g.Sheeba T.M.Selvarajan Department of Mathematics Government Engineering CollegeTrivandrum695035India Department of Mathematics Noorul Islam Centre for Higher EducationKumaracoilThuckalay629175India

Wireless sensor networks(WSNs)are one of the most important improvements due to their remarkable capacities and their continuous growth in various ***,the lifetime of WSNs is very confined because of the delimited energy limit of their sensor *** is the reason why energy conservation is considered the main exploration worry for *** this energy-efficient routing is required to save energy and to subsequently drag out the lifetime of *** this report we use the Ant Colony Optimization(ACO)method and are evaluated using the genetic Algorithm(ga),based on the Detour non-split dominant set(ga)In this research,we use the energy efficiency returnee non-split dominating set(DNSDS).A set S⊆V is supposed to be a DNSDS of g when the graph g=(V,E)is expressed as both detours as well as a non-split dominating set of *** the detour non-split domination number be addressed asγ_dns(g)and is the minimum order of its detour non-split dominating *** DNSDS of orderγdns(g)is aγdns-set of ***,theγ_dns(g)of various standard graphs is resolved and some of its general properties are contemplated.A connected graph usually has an order n with detour non-split domination number as n or n–1 are *** connected graphs of order n≥4 and detour diameter D≤4 with detour non-split dominating number n or n−1 or n−2 are additionally *** considering any pair of positive integers to be specific a and b,there exists a connected graph g which is normally indicated as dn(g)=a,γ(g)=b andγdns(g)=a+b−2,hereγdns(g)indicates the detour domination number and dn(g)indicates the detour number of a *** time is taken for the construction and the size of DNSDS are considered for examining the performance of the proposed *** simulation result confirms that the DNSDS nodes are energy efficient.

关键词： Domination number non-split domination number detour number detour non-split domination number

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Role of the intestinal barrier in inflammatory bowel disease

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World Journal of gastroenterology 2008年第3期14卷 401-407页

作者： Mike g Laukoetter Porfirio Nava Asma Nusrat Epithelial Pathobiology Research Unit Department of Pathology and Laboratory Medicine Emory University Atlanta GA 30322 United States Department of General Surgery University of Muenster Muenster 48149 Germany Epithelial Pathobiology Research Unit Department of Pathology and Laboratory Medicine Emory University Atlanta GA 30322 United States

A critical function of the intestinal mucosa is to form a barrier that separates luminal contents from the interstitium. The single layer of intestinal epithelial cells (IECs) serves as a dynamic interface between the host and its environment. Cell polarity and structural properties of the epithelium is complex and is important in the development of epithelial barrier function. Epithelial cells associate with each other via a series of intercellular junctions. The apical most intercellular junctional complex referred to as the Apical Junction Complex (AJC) is important in not only cell-cell recognition, but also in the regulation of paracellular movement of fluid and solutes. Defects in the intestinal epithelial barrier function have been observed in a number of intestinal disorders such as inflammatory bowel disease (IBD). It is now becoming evident that an aberrant epithelial barrier function plays a central role in the pathophysiology of IBD. Thus, a better understanding of the intestinal epithelial barrier structure and function in healthy and disease states such as IBD will foster new ideas for the development of therapies for such chronic disorders.

关键词： Intestine Barrier function Tight Junction InflammatorY bowel disease Crohn's disease Ulcerativecolitis

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LSgMC5含量对于二甲醚燃料电池复合Ni-Fe阳极性能的影响

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物理化学学报 2007年第4期23卷 473-478页

作者：贺琼王世忠厦门大学化学化工学院化学系福建厦门361005

用浸渍法制备了掺杂不同质量分数的La_(0.8)Sr_(0.2)ga_(0.8)Mg_(0.15)Co_(0.05_O_(3-δ)(LSgMC5)粉末的Ni8-Fe2-LSgMC5复合阳极,并采用交流阻抗和直流极化技术考察了以氢气和二甲醚为燃气时该复合阳极的电化学性能及相应电池的功率输... 详细信息

用浸渍法制备了掺杂不同质量分数的La_(0.8)Sr_(0.2)ga_(0.8)Mg_(0.15)Co_(0.05_O_(3-δ)(LSgMC5)粉末的Ni8-Fe2-LSgMC5复合阳极,并采用交流阻抗和直流极化技术考察了以氢气和二甲醚为燃气时该复合阳极的电化学性能及相应电池的功率输出特性.结果表明,在电极中掺入LSgMC5粉末,能显著地改善电极的形貌和电极/电解质界面结构,减小欧姆电阻和极化电阻.电极中LSgMC5粉末含量对于氢气及二甲醚电化学氧化性能的影响显著不同.以二甲醚为燃气时,电极极化电阻随LSgMC5粉末含量的增加而减小,其中LSgMC5掺杂量为30%的复合阳极具有最高的电化学性能,相应电池在1073、1023、973K时的输出功率分别为1.00、0.61、0.40W·cm^(-2);以氢气为燃气时,LSgMC5掺杂量为20%的复合阳极具有最好的电化学性能,随着LSgMC5掺杂量的进一步增加,电极极化电阻显著增大.

关键词：固体氧化物燃料电池复合Ni—Fe阳极交流阻抗极化二甲醚

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IL-6基因多态性与COPD发病风险关系的Meta分析

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中国循证医学杂志 2014年第9期14卷 1131-1134页

作者：魏江涛候明勇何斌邓磊廖玍成都大学附属医院麻醉科成都610081 四川大学华西口腔医院口腔疾病研究国家重点实验室成都610041

目的系统评价白细胞介素6(IL-6)基因-174g/C多态性与慢性阻塞性肺疾病(COPD)发病风险的相关性。方法计算机检索PubMed、EMbase、CNKI、WanFang Data、CBM和VIP数据库有关IL-6基因-174g/C多态性与COPD发病风险的病例-对照研究,检索时限... 详细信息

目的系统评价白细胞介素6(IL-6)基因-174g/C多态性与慢性阻塞性肺疾病(COPD)发病风险的相关性。方法计算机检索PubMed、EMbase、CNKI、WanFang Data、CBM和VIP数据库有关IL-6基因-174g/C多态性与COPD发病风险的病例-对照研究,检索时限均为从建库至2013年6月。由2位研究者按纳入与排除标准独立筛选文献、提取资料后,采用RevMan 5.2软件进行Meta分析。结果最终纳入5个研究,共计487例COPD患者和786例对照。Meta分析结果显示IL-6基因-174g/C多态性和COPD发病风险无相关性:gC+CC ***:OR=1.01,95%CI(0.76,1.34),P=0.95;CC ***+gg:OR=1.04,95%CI(0.70,1.54),P=0.85;CC ***:OR=1.05,95%CI(0.69,1.61),P=0.81;gC ***:OR=1.00,95%CI(0.74,1.35),P=0.99;C vs.g:OR=1.02,95%CI(0.83,1.24),P=0.88。结论 IL-6基因-174g/C多态性可能不是COPD发病风险的危险因素。

关键词：慢性阻塞性肺疾病 IL-6 多态性 Meta分析病例一对照研究

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