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Bowland Shale well placement strategy-Part 2:Fracture simulations using a 3d geomechanical model and implications for stratigraphic and spatial horizontal well locations

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Energy Geoscience 2022年第3期3卷 235-254页

作者： Iain de Jonge-Anderson Jingsheng ma Xiaoyang Wu dorrik Stow david Griffiths Institute of GeoEnergy Engineering(IGE) School of EnergyGeoscienceInfrastructure&SocietyHeriot-Watt UniversityEdinburghEH144ASUK British Geological Survey The Lyell CentreResearch Avenue SouthEdinburghEH144APUK Penrhyn Exploration UK

Hydraulic fracture modelling is a key component of a shale reservoir well placement strategy as it provides an indication of the typical lengths and heights of stimulated fractures and of the changes to the stress environment in which these are ***,spatial and stratigraphic variations in the stress and geomechanical properties of shales make accurate modelling a challenging *** the UK Bowland Shale,stacked horizontal wells targeting multiple stratigraphic intervals could be used to avoid large offset faults in a geologically complex ***,it is not known how these intervals may respond to hydraulic fracturing and predicting the height and length of hydraulic fractures is necessary in order to assess the likelihood of vertical fracture interference across landing zones or propagation towards major *** the case of the former,intervals of high effective stress may be key to containing fractures within their desired *** a planar hydraulic fracture simulator,and a 3d geomechanical model incorporating dipping stratigraphy,the issue of predicting hydraulic fracture geometry in the Bowland Shale was assessed through a series of modelling exercises using well Preese Hall-1 and horizontal *** pre-defined landing zones were targeted,narrow and long transverse fractures around 1 km from the well were *** the simulation design mimicked perforation clusters placed at 12 m intervals along horizontal pseudo-wells,the effects of stress shadowing were acute and resulted in irregular fracture ***,high effective stress intervals performed efficiently as barriers to vertical hydraulic fracture propagation,reinforcing the feasibility of using stacked production for the Bowland *** modelling results were then used to discuss the possible placement of horizontal wells in a mapped,100 km2 region around well Preese Hall-1,where up to 13 sites could be positioned,with a horizontal well length of aroun

关键词： Bowland Shale Hydraulic fracturing Geomechanics Fracture simulation Well placement

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Modelling and Sizing of a Floor Reinforced by Ballasted Columns Intended to Support a Tank

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Open Journal of Civil Engineering 2024年第3期14卷 405-420页

作者： Cheikh diallo diène madièye Fall Souka Bidzha Harlin Sylvaire Laboratory of Modelling and Soil Mechanics Electrical and Building School (ESEBAT) Dakar Senegal

This work aims to study the modeling and sizing of a floor reinforced by ballasted columns. We are studying the system of reinforcement by ballasted columns because this technique is able to replace deep foundations that are technically difficult to realize and their cost is higher. The modelling and dimensioning of foundations on a ballasted column will be an important contribution to the state of the art of this method because it will highlight the mode of transfer of loads, and will expose the induced deformations by also allowing to verification criteria of bearing capacity and allowable settlement according to geometric information of the model. The columns on a substrate located at 9 m have a length of 9 m and a diameter of 40 cm and were obta.ned by incorporating ballast of granular class 0/31.5 of internal friction angle of 38˚ and a density weight of 21 kN/m3. The choice of this method is based on the geotechnical characteristics of the initial soil. Thus, identification and characterization tests were carried out to estimate the bearing capacity and the settlement giving respectively 125 kPa and 57 cm. These results show the ground does not have sufficient mechanical properties to withstand the loads transmitted by the tank. By adopting the reinforcement of the soil with ballasted columns, numerical calculations show that after applying a load equal to 265.1 KPa, 20 cm vertical settlement and 17 cm horizontal displacement were obta.ned. This is in the tolerable deformation range for our tank, namely, less than 20 cm. Analytically, in addition to reducing settlement, ballasted columns, due to their high stiffness, they have effectively contributed to the increase of the permissible soil stress up to 257 kPa.

关键词： Reinforcement Ballasted Columns Reservoir Geotechnical Modeling Plaxis 2d

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Epidemiological Approach to Understand Rheumatic Heart Valve disease: Case of Thoracic Cardiovascular Clinic of Fann Hospital (dakar)

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World Journal of Cardiovascular diseases 2020年第10期10卷 750-760页

作者： marie Parsine Sall Fatimata Mbaye Mbacké Sembéne Amadou Gabriel Ciss département de Biologie Animale Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Sénégal Institut de Recherche Pour le développement Campus Bel-Air Université Cheikh Anta Diop Dakar Sénégal Faculté de Médecine de Pharmacie et D’odontologie Université Cheikh Anta Diop Dakar Sénégal

Objective: Rheumatic heart disease is the major cause of heart valve disease in developing countries. In Senegal, cardiac pathology is dominated by rheumatic pathology whose hospital prevalence was estimated at 0.15% [1]. Epidemiological data on rheumatic heart valve disease (RHVD) are unfortunately imprecise due to the lack of good quality data collection in a large number of countries, especially in sub-Saharan areas and in Central Asia. The objective of this epidemiological study is to collect data about rheumatic heart valve disease in our clinic which is the only surgical center of Senegal. Patients and Methods: Our study conducted between 2014 and 2017 involved a population of one hundred and eighty-three patients with complete medical records, all followed at the Thoracic and Cardiovascular Surgery Clinic at Fann Hospital for rheumatic valve disease. This population was the subject of an epidemiological survey based on a questionnaire covering clinical parameters as consanguinity, clinical signs, diagnosis and surgical intervention. Results: Our work is an epidemiological study involving one hundred and eighty-three (183) patients with various types of rheumatic valve disease, followed at the Thoracic and Cardiovascular Surgery Clinic at Fann Hospital, and who responded to a questionnaire about clinical aspects of this disease. Our results showed 5.46% of family cases, of which 2.18% came from consanguineous marriages. Mean age at onset of clinical signs was 14 ± 9 years with 14.20% before 6 years of age, 65.91% between

关键词： Rheumatic Valves Epidemiological diagnosis Surgery

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Ovarian Tumors in Senegalese Women: Impact of d-Loop Mutations between Healthy and Cancerous Tissues

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Open Journal of Genetics 2024年第2期14卷 37-46页

作者： Rouguiyatou Ka Fatimata Mbaye Bineta Kénéme Mbacké Sembène Genomics Laboratory Department of Animal Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal

In Senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of genetic predisposition. The sequencing of the human genome, which has led to the discovery of millions of sequence variations, makes it possible to study variations within sequences. These variations are limited to Single Nucleotide Polymorphisms (SNPs) and this common form of polymorphism occurs approximately every 1000 bases in the human genome and 1.8 million SNPs are currently listed according to [1]. The aim of this study is to gain a better understanding of the impact of mutations in the d-loop region of mtdNA on ovarian cancer in Senegalese women. This study involved searching for mutations in our study population after dNA extraction and sequencing. Mutations were found after a comparison of our sequences with the Cambridge reference sequence (NC_012920). The mutations found in the dNA studied extend from position 7 to position 16568 and most of these mutations are located in the hypervariate zones (HV1 and HV2). Heteroplasmy with three mutant alleles was also found in certain variants. Common mutations were found in both healthy and cancerous tissues, with almost identical frequencies in both types of tissue. This enabled us to understand the spread of tumor cells throughout the ovary.

关键词： Ovarian Cancer Mutations d-Loop Heteroplasmy

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Construction of an Unusual Two-dimensional Layered Structure for Fused-Ring Energetic materials with High Energy and Good Stability

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Engineering 2020年第9期6卷 1136-1143页

作者： Yongan Feng Mucong deng Siwei Song Sitong Chen Qinghua Zhang Jean’ne M.Shreeve department of Chemistry University of IdahoMoscowID 83844-2343USA Institute of Chemical materials China Academy of Engineering PhysicsMianyang 621900China

制造具有良好机械感度的高性能含能材料在过去几十年里一直是一项重大挑战,因为这类蕴含巨大能量的材料存在内在的不稳定性。本文研究了一种极具潜力的稠环含能材料:4-硝基-7-叠氮基-吡唑-[3,4-d]-1,2,3-三嗪-2-氧(NAPTO)。这种物质具... 详细信息

制造具有良好机械感度的高性能含能材料在过去几十年里一直是一项重大挑战,因为这类蕴含巨大能量的材料存在内在的不稳定性。本文研究了一种极具潜力的稠环含能材料:4-硝基-7-叠氮基-吡唑-[3,4-d]-1,2,3-三嗪-2-氧(NAPTO)。这种物质具有不同寻常的二维(2d)层状结构,其绝对结构已经单晶X射线衍射证实。研究显示,这一结构新颖的含能物质具有惊人的能量[如爆速(d)高达9.12 km·s^-1,爆压(P)为35.1 GPa]、优异的机械感度[撞击感度(IS)为18 J、摩擦感度(FS)为325 N、静电感度(EdS)为0.32 J]和良好的热分解温度(203.2℃),展示出高能量与低感度的双重优势。据我们所知,NAPTO是首个具有二维层状结构的稠环含能材料。与此同时,运用分子模拟分析了其在外界机械刺激下的稳定机制,结果表明,该含能材料超平的二维层状结构比其他结构更能有效地缓冲外界机械刺激,从而将作用在材料上的机械能转化为晶体的层间滑动与压缩。本研究从实验和理论两个方面揭示了稠环二维层状结构在制造先进含能材料方面的巨大潜力。

关键词：含能材料稠环杂环化合物二维层状结构高能量稳定性感度

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Causes of maternal Mortality in 2020 in the Kara Region (Togo)

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Open Journal of Obstetrics and Gynecology 2022年第1期12卷 104-111页

作者： dédé Régine diane Ajavon Logbo-Akey Kossi Edem Kambote Yendoube Agoro Sibabe Ali Hélène Beley Christine Aledi Tchilalo Sodou Pouzouwè Gnakou Louise Aboubakari Abdoul Samadou department of Obstetric Gynecology University of Kara Kara Togo Kara Regional Health directorate Kara Togo National School of Midwives of Kara Kara Togo

Objective: determine the maternal mortality rate, the epidemiological profile, the causes of death and the dysfunctions noted. Patients and method: This was a cross-sectional and descriptive study from January 1 to december 31, 2020. All maternal deaths during pregnancy or within 42 days after its termination fitting the World Health Organisation definition criteria that occurred in the seven districts of Kara region were included. The data were processed using Excel microsoft. Results: A total of 41 maternal deaths occurred among 23,456 live births, accounting for a maternal mortality ratio of 174.8 deaths per 100,000 live births. The followings were observed: the average age of 30 years;88% married;39% multiparous;78% housewives without income; 5% students. Hemorrhage, preeclampsia, and complications of abortion were the main direct obstetric causes, while anemia was the main indirect obstetric cause. Factors related to deaths were inadequate quality of health care and lack of universal health insurance. The various maternal death audit reports found that 94.4% of deaths were preventable. Conclusion: Most maternal deaths would be prevented in the Kara region if women during pregnancy and the postpartum period received quality health care and the community was involved in decision-making about their health.

关键词： maternal deaths Audit Causes Preventable

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Preclinical and clinical evidence of the association of colibactinproducing Escherichia coli with anxiety and depression in colon cancer

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World Journal of Gastroenterology 2024年第21期30卷 2817-2826页

作者： Fabien Rondepierre maëva Meynier Johan Gagniere Vincent deneuvy Anissa deneuvy Gwenaelle Roche Elodie Baudu Bruno Pereira Richard Bonnet Nicolas Barnich Frédéric Antonio Carvalho denis Pezet mathilde Bonnet Isabelle Jalenques Service de Psychiatrie de l’Adulte A et Psychologie Médicale CHU Clermont-FerrandClermont-Ferrand 63000France M2iSH UMR 1071INSERMUniversity of Clermont AuvergneINRAE USC 1382Clermont-Ferrand 63001France neurodol UMR 1107INSERMUniversity of Clermont AuvergneClermont-Ferrand 63001France department of digestive Surgery CHU de Clermont-FerrandClermont-Ferrand 63001France Biostatistics Unit Department of Clinical Research and InnovationCHU Clermont-FerrandClermont-Ferrand 63000France department of Bacteriology CHU de Clermont-FerrandClermont-Ferrand 63001France UniversitéClermont Auvergne INPCNRSClermont Auvergne Institut PascalClermont-Ferrand 63000France

BACKGROUNd The association between the intestinal microbiota and psychiatric disorders is becoming increasingly *** gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin-producing Escherichia coli(CoPEC).AIM To evaluate the association between CoPEC prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical *** Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric *** were compared according to the CoPEC *** parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC *** behavior was assessed using the Elevated Plus maze test,the Forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without CoPEC *** result was confirmed in C57BL6/J wildtype mice and in a CRC susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a CoPEC *** This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.

关键词： Colorectal cancer Colibactin Escherichia coli Colibactin-producing Escherichia coli Inflammation Anxiety depression Behavior

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Pozzolanic Activity of Old Volcanic Tuffs of mako Area (Senegal-Oriental, West African Craton): An Economic and Environmental Interest

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International Journal of Geosciences 2019年第3期10卷 225-237页

作者： matar Ndiaye mahamadane diène Mouhamadou Bassir diop Papa malick Ngom I. S. T. BP: 5396 F Sciences et Techniques Université Cheikh Anta Diop de Dakar Dakar Sénégal département de géologie Faculté des Sciences et Techniques Université Cheikh Anta Diop de Dakar Dakar Sénégal

The volcanic tuffs of Senegal-Oriental in mako area are produced during a calc-alkaline volcanism which occurs in this region and which is dated from about 2.3 - 1.95 Ga. despite their altered appearance, the X-Ray diffractions show mineral paragenesis: Quartz-Kaolinite-Illite and an important amorphous phase. On the Ternary Keil-Rankin diagram for the CaO-SiO2-Al2O3 the volcanic tuffs of mako area are situated between pozzolan and the fly ash. The difference between silica and lime is greater than 34% in these volcanic tuffs. In this study, they have been mixed with Portland cement to obtain pozzolanic cements respectively with 20%, 30%, 35% and 40% of addition of volcanic tuffs. The pozzolanic reactivity is highlighted by the compressive strength increase until 90 days of conservation in water. It supposes that the vitreous phase of the volcanic tuffs reacts with the free CaO (CaOf) of Portland cement to produce new hydrated minerals. This study has a positive economic and environmental impact. Because the time of grinding of pozzolanic cements is reduced. Also, the addition of volcanic tuffs reduces the production of clinker, then the CO2 emission.

关键词： Old Volcanic Tuffs Calc-Alkaline X-Ray diffractions Amorphous Pozzolanic Cements Compressive Strength Economic Environmental

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Morphology, Thermal Behavior and dynamic Rheological Properties of Wood Polypropylene Composites

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materials Sciences and Applications 2013年第11期4卷 730-738页

作者： diène Ndiaye Vincent Verney Haroutioun Askanian Sophie Commereuc Adams Tidjani département de Physique Université Cheikh Anta Diop Dakar Sénégal Institut de Chimie de Clermont-Ferrand Université Blaise Pascal Clermont-Ferrand France CNRS UMR 6296 ICCF Université Blaise Pascal Aubière France Institut de Chimie de Clermont-Ferrand Université Blaise Pascal Clermont-Ferrand France Ecole Nationale Supérieure de Chimie de Clermont-Ferrand Université Blaise Pascal Clermont-Ferrand France Section Physique Appliquée Université Gaston Berger Saint-Louis Sénégal Institut de Chimie de Clermont-Ferrand Université Blaise Pascal Clermont-Ferrand France Ecole Nationale Supérieure de Chimie de Clermont-Ferrand Université Blaise Pascal Clermont-Ferrand France

Wood polymer composites (WPCs) were made with pine and polypropylene matrix (PP). The composites were produced by melt blending in a Brabender at 180°C. Characterization of the samples, with the aid of scanning electron microscopy supplemented by microscope photography, showed an improved dispersion of wood in the polymeric material in presence of polypropylene grafted with maleic anhydride (maPP) or nanoclay. The use of the maPP instead of clay seems to have enhanced the level of crystallinity in the composites for the same levels of wood loading and also accelerates the crystallization. Melt rheological measurements of neat PP and PP-wood composites were carried out at 180°C with an ARES Rheometer scientific mechanical spectrometer in oscillatory frequency. All the composites materials exhibit viscoelastic values greater than those for neat PP. The samples containing maPP as comptabilizer show the higher newtonian viscosity, however, the addition of a small concentration of nanoparticles like nanoclays does not improve the resulting melt viscoelastic behavior of the composite.

关键词： Morphology Thermal Behavior dynamic Rheological Properties Wood Polypropylene Composites

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Tracing Water Flow and Colloidal Particles Transfer in an Unsaturated Soil

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Journal of Water Resource and Protection 2014年第7期6卷 696-709页

作者： dieuseul Prédélus Laurent Lassabatere Artur Paiva Coutinho Cédric Louis Thomas Brichart Erij Ben Slimène Thierry Winiarski Rafael Angulo-Jaramillo Nano-H S.A.S. 38070 Saint Quentin Fallavier France Universidade Federal de Pernambuco Recife Brazil Université de Lyon CNRS UMR 5023 LEHNA ENTPE Vaulx-en-Velin France Universidade Federal de Pernambuco Recife Brazil

In recent years, many studies have been carried out on colloidal particle transfer in the unsaturated zone because they can be a risk to the environment either directly or as a vector of pollutants. A study was conducted on the influence of porous media structure in unsaturated conditions on colloidal particle transport. Three granular materials were set up in columns to replicate a fluvio-glacial soil from the unsaturated zone in the Lyon area (France). It is a sand, a bimodal mixture in equal proportion by weight of sand and gravel, and a fraction of bimodal mixture. Nanoparticles of silica (SiO2-Au-FluoNPs), having a hydrodynamic diameter between 50 and 60 nm, labeled by organic fluorescent molecules were used to simulate the transport of colloidal particles. A nonreactive tracer, bromide ion (Br-) at a concentration of C0,s = 10-2 M was used to determine the hydrodispersive properties of porous media. The tests were carried out first, with a solution of nanoparticles (C0,p = 0.2 g/L) and secondly, with a solution of nanoparticles and bromine. The transfer model based on fractionation of water into two phases, mobile and immobile, MIM, correctly fits the elution curves. The retention of colloidal particles is greater in the two media of bimodal particle size than that in the sand, which clearly demonstrates the role of textural heterogeneity in the retention mechanism. The increase in ionic strength produced by alimenting the columns with colloidal particle suspension in the presence of bromide, increases retention up to 25% in the sand. The total concentration profile of nanoparticles collected at the end of the experiment shows that the colloidal particles are reta.ned primarily at the entrance of the columns. Hydrodispersive calculated parameters indicate that flow is more heterogeneous in bimodal media compared to sand.

关键词： Colloidal Particle Transport Microstructure Modeling Unsaturated Soil

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