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Open Journal of Geology 2023年第10期13卷 1024-1053页

作者： Bernadin Gnamou Hermann Ilboudo Wilfried Antoine Bassou Toé sâga sawadogo Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Ouagadougou Burkina Faso

In the Mangodara area within the Banfora greenstone belts (Baoulé-Mossi domain of the West African Craton), our study focused on geochemical assessment of the mobility of major and trace elements. Gold and base metal occurrences are hosted in highly metamorphic felsic (metarhyolite) and intermediate (metadacite and metaandesite) formations. Common mineral assemblages made up of staurolite - kyanite - pyrophyllite are interpreted to represent the metamorphosed equivalent of aluminous hydrothermal alteration. Associated felsic and intermediate volcanic rocks are enriched in Fesub>2sub>Osub>3sub>, Ksub>2sub>O (metaandesite, metarhyolite) and depleted in MgO, Alsub>2sub>Osub>3sub>, CaO, Psub>2sub>Osub>5sub>, Nasub>2sub>O (metarhyolite) and Fesub>2sub>Osub>3sub>, MgO, CaO (metaandesite). Alsub>2sub>Osub>3sub> depletion in mineralized kyanite-staurotide bearing metarhyolites suggests corroded minerals. Mineralized metarhyolites show enrichment in Au, Ag, Ba, Bi, Cr, Cu, Eu, La, Mo, Ni, Pb, s, sc, V and depletion in As sb Co, sn, Zn while mineralized metaandesites show enrichment in Au, Ag, As, Mo, s, sb and depletion in Co, sn, Zn, Bi, Cr, Cu, Eu, Ni, Pb, sc. Ba, La, V are immobile in metaandesites. Finally, Ag, As, sn appear as geochemical vectors for gold exploration in the study area since gold mineralization is characterized by Au + Ba + Cu + Eu + La + Mo + Ni + s association in metarhyolites and Au + s + sb + As + Ag + Bi in metaandesites.

关键词： Geochemical Mobility Aluminous Alteration Metamorphism Gold Base Metal Banfora Greenstone Belts Mangodara

Alteration Typology and Geochemical signatures of the Napélépéra Gold-Bearing Granodiorite in south-West Burkina Faso (West Africa)

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Open Journal of Geology 2023年第10期13卷 1162-1175页

作者： Théophile Ouédraogo sâga sawadogo Hermann Ilboudo séta Naba Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph KI-ZERBO Ouagadougou Burkina Faso

The characterization of the relationships between mineralization and hydrothermal alteration is an essential element in understanding gold deposits. In south-west Burkina Faso, the Napélépéra mineralisation, the mobility of chemical elements and alteration-mineralization relationships were studied by means of selected core drilling and geochemical analyses using ICP-Ms (Inductively Coupled Plasma Mass spectrometry) and ICP-AEs (Inductively coupled plasma atomic emission spectroscopy). The mineralised granodiorite is grey porphyroid with quartz, plagioclase, biotite and amphibole. It is metaluminous and located in the tholeiitic series. The Nasub>2sub>O + CaO versus Fesub>2sub>Osub>3sub> + MgO alteration diagram divides the samples according to alteration dominance. Chloritisation and carbonation are the main alterations. There is a relationship between gold mineralisation at Napélépéra and alteration, and the paragenesis of gold + pyrite ± carbonate ± silica ± sericite is the main characteristic. Carbonation is the result of fluid input in the shear corridor of the mineralised zone. The mass balance of comparative metals in the proximal and distal zones of the mineralisation shows the absence of metals, while As, Hg, Ag and Bi are strongly enriched from the distal zone to the mineralised zone. The oxides associated with the mineralisation are mainly NaO, srO and CaO.

关键词： Gold Mineralization Alteration Mass Balance Granodiorite

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

Perspectives in restoration: storage and pretreatments of seeds for better germination of sudanian savanna-woodland species

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Journal of Forestry Research 2016年第4期27卷 773-778页

作者： s.D.Dayamba P.savadogo s.Diawara L.sawadogo World Agroforestry Centre (ICRAF) West and Central Africa Regional Office - Sahel Node World Agroforestry Centre & International Crop Research Institute for the semi-Arid Tropics (ICRAF-ICRIsAT) West and Central Africa Region-Sahel Node De'partement Productions Forestie`res Centre National de la Recherche Scientifique et Technologique Institut de l’Environnement et de Recherches Agricoles

Insufficient knowledge of the germination ecology of local species is one of the main constraints to restoration of degraded rural lands. We tested seeds from fourteen sudanian savanna species targeted for restoration for their response to two different pretreatments（conventional and prolonged acid pretreatments） and two different storage conditions（ambient room conditions and refrigerator at 4 C）. For 6 of the studied species, longer soaking in sulphuric acid significantly improved germination rates and also reduced the germination time of some species. storage condition, in general did not affect germination rates except for two species where cool storage depressed germination. The practical implication is that, for the species tested, when mature seeds are collected for plantation in the upcoming rainy season, there is no need to invest in infrastructure and energy for storing in cold *** study also revealed that in general when seeds are stored in ambient conditions from the time of collection up to seeding time, although germination rate does not increase, germination time is shortened and this could be of great interest in synchronizing germination in real field conditions.

关键词： germination restoration plantation ambient mature stored ecology degraded shortened longer

Photovoltaic waste management in sub-saharan Africa:current practices in Burkina Faso

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Waste Disposal and sustainable Energy 2024年第2期6卷 271-282页

作者： Kodami Badza Yrebegnan Moussa soro Marie sawadogo Laboratoire Energies Renouvelables et EfficacitéEnergétique Institut International d'Ingenierie de I'Eau et de I'Environnement(2iE)01 BP 594 OuagadougouBurkina Faso

sub-saharan Africa is witnessing a proliferation of photovoltaic(PV)waste due to the increasing number of solar PV power *** waste(panels,batteries,electrical cables,mounting structures,and inverters)consists of elements such as mercury,cadmium,chromium,lead,copper,aluminum,fluorinated compounds,and plastics that are toxic to human health and the environment if a proper management system is not *** many studies worldwide have focused on PV waste management,very few have been conducted in sub-saharan *** study aims to investigate the current PV waste management system in Burkina Faso,determine stakeholder profiles,and propose strategies to enhance the existing *** research,interviews,questionnaires,and field visits were used in the *** survey showed that young people,mainly under 30 years of age and with a primary education,dominate(70%)in terms of PV waste collection and repair activities,while the more technical recycling and export activities are carried out mainly(88%)by stakeholders older than 40 years and with a secondary education(60%).Among the older stakeholders,100%are aware of the hazardous nature of PV waste,whereas 36%are young *** an environmental perspective,the main source of contamination observed is the release of lead-rich sulfuric acids into water and soil during the collection and repair *** the recycling of batteries and electrical cables,toxic fumes are emitted into the air,and recycling residues rich in toxic substances are *** reduce risks to human health and the environment when managing PV waste,the introduction of legislation,the multiplication of collection points and appropriate infrastructures,the training and awareness-raising of stakeholders,and the extended responsibility of manufacturers are *** on the economic feasibility of setting up formal management structures are needed to complete this work.

关键词： Photovoltaic waste sub-saharan Africa Waste management Recycling Batteries Incineration

Physical and coupled fully three-dimensional numerical modeling of pressurized bottom outlet flushing processes in reservoirs

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International Journal of sediment Research 2019年第5期34卷 461-474页

作者： Ousmane sawadogo Gerrit R.Basson simon schneiderbauer Department of Civil Engineering Stellenbosch University Christian-Doppler Laboratory for Multi-scale Modelling of Multiphase Processes Johannes Kepler University

sediment deposition in reservoirs is an important research topic in engineering practice. Reservoir sedimentation has the potential to affect flood levels, drainage for agricultural land, pump station and hydropower operation as well as navigation. This paper describes the development of a coupled fully three-dimensional(3 D) numerical model for the prediction of the local sediment flushing scour upstream of the bottom outlet. The presented numerical model solves the Navier-stokes equations in conjunction with the k-ε turbulence model which includes both sediment transport and hydrodynamic parameters. The proposed coupled fully 3 D numerical model is used to simulate experimental tests based on non-cohesive sediment. The geometric features of the scour hole(temporal and spatial hole development) upstream of the bottom outlet were reasonably well predicted compared to the experimental data. Furthermore, the velocity field upstream of the bottom outlet was in good agreement with measurements. The proposed numerical model for bottom outlet flushing was, therefore, validated because of its ability to accurately predict the scour hole development during the flushing process. The proposed numerical model can be considered reliable provided that the model is correctly calibrated and set up to reflect the conditions of a particular case study.

关键词： Bottom outlet Coupled flow/sediment model sediment flushing 3D numerical model Packed bed Reservoir

Bt cotton seed purity in Burkina Faso:status and lessons learnt

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Journal of Cotton Research 2020年第4期3卷 260-267页

作者： BOURGOU Larbouga KARGOUGOU Ester sawadogo Mahamadou FOK Michel INERA Programme CotonBP 208Bobo-DioulassoBurkina Faso sOFITEX Laboratoire Contrôle QualitéSemences01 BP 147Bobo-Dioulasso 01Burkina Faso UniversitéOuaga1 Joseph Ki-Zerbo 09 BP 848Ouagadougou 09Burkina Faso CIRAD F-34398 MontpellierFrance UPR AIDA Univ MontpellierMontpellierFrance.

Background:since the commercial release of Bt cotton in Burkina Faso in 2009,the issue of seed purity in producers’fields has rarely been addressed in an unbiased and objective *** potential for contamination of conventional seed varieties with Bt traits and the consequent threat to the continuation of organic cotton production has been ***,studies are rare on the varietal purity of Bt cotton seeds,despite the implications for the effectiveness and sustainability of their *** paper compensates for the lack of research on the varietal purity of cotton seeds in Burkina Faso by reporting the results of Enzyme linked immunosorbent assay tests collected in 2015 on samples of both conventional and Bt varieties from 646 ***:According to the conservative criteria used to declare the presence of a Bt gene in a given variety(more than 10%of seeds of conventional variety exhibit Bt traits,and at least 90%of seeds of Bt variety exhibit Bt traits),seed purity was very questionable for both types of *** the supposedly conventional variety,the Cry1Ac gene was observed in 63.6%of samples,the Cry2Ab gene was observed in 59.3%of samples,and both genes were detected in 52.2%of the seed *** 29.3%of the seeds that were supposed to be of conventional type contained no Bt ***,for the labeled Bt variety,the Cry1Ac gene was found in only 59.6%of samples,the Cry2Ab gene was found in 53.6%of the samples,and both genes were found in 40.4%of the ***,for the seeds that were supposed to contain both genes(Bollguard 2),both Cry1Ac and Cry2Ab genes were found in only 40.4%of the samples,only one of the genes was found in 32.4%of the samples,and 27.2%of the seeds in the samples contained *** factors are responsible for the severe lack of seed ***,conventional varieties are being contaminated with Bt traits because of a failure to revise the seed production scheme in Burkina Faso to prevent cross-pollinat

关键词： Conventional cotton Organic cotton GM cotton seed production scheme seed control Burkina Faso

Phenotypic and Genotypic Antibiotic Resistant Diarrheagenic Escherichia coli Isolated from Patients with Diarrhea in Ouagadougou, Burkina Faso

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Advances in Microbiology 2023年第7期13卷 347-359页

作者： Haoua Cissé Assèta Kagambèga soutongnooma Caroline Bouda Abdallah sawadogo Nicolas Barro Laboratoire de Biologie Molé culaire d’Epid&eacutemiologie et de Surveillance des agents Transmissibles par les Aliments (LaBESTA) Universit&eacute Joseph KI-Zerbo Ouagadougou Burkina Faso Ecole Normale supé rieure (ENS) Ouagadougou Burkina Faso

Background: The emergence and spread of multidrug-resistant bacteria have become a major public health problem worldwide, particularly in developing countries such as Burkina Faso. This study aims to determine phenotypic and genotypic antibiotic resistant diarrheagenic Escherichia coli (DEC) from patients with diarrhea in Ouagadougou, Burkina Faso. Methodology: Microbiological and biochemical analysis were done to detect two hundred and ninety-two (292) strains. The susceptibility of the strains to antibiotics was determined by the agar disc diffusion method. 16-plex-PCR assays were carried out to detect both virulence and resistance genes encoding betalactams, quinolones, phenicols, tetracyclines and virulence gene of DEC. Results: Diarrheagenic Escherichia coli was detected in 8% (23/292) of patients with diarrhea using the 16-plex-PCR and 39.1% (9/23) of the DEC detected carry at least one resistance gene. Resistance rate in disc diffusion test was 86.96% to tetracycline, 65.23% to cotrimoxazole, 17.4% to nalidixic acid, 17.4% to norfloxacin, 17.4% to ciprofloxacin, 13.04% to ceftriaxone, 13.04% to cefotaxime, 8.7% to gentamicin, 8.7% to Chloramphenicol, 0% to netilmicin. The prevalence of different resistance genes in the studied strains varied from 44.4% to 5.5%. The gene Tet coding for resistance to tetracycline was found in 8 strains (44.4%). The CatA gene coding for resistance to Chloramphenicol was detected in 38.9% of isolates. The qnrs, blasub>sHVsub> and blasub>OXAsub> genes were each detected in 5.5% of isolates. No strain hosts the qnrA, qnrB and blasub>TEMsub> genes. Conclusion: This study identified β-lactams, quinolones, phenicols and tetracyclines resistance genes in DEC isolates from patients with diarrhea in Ouagadougou, Burkina Faso. These results indicate the need for a surveillance program to reduce the prevalence of resistance to Enterobacteriaceae strains in hospitals.

关键词： Diarrheagenic Escherichia coli Phenotypic Genotypic Resistance Ouagadougou

Between Euthanasia and Dysthanasia: The Ethical Issue of sedation in the Terminal Phase of Illness

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Journal of Biosciences and Medicines 2024年第2期12卷 39-49页

作者： Joseph sawadogo Faculty of Human and social sciences Department of Philosophy Faculty of Medicine University Saint Thomas d’Aquin (USTA) Ouagadougou Burkina Faso

Background: Deep sedation, euthanasia and therapeutic relentlessness lead us today to rethink the paradigm of life and the contingency of human existence. Between therapeutic relentlessness, the unreasonable care which uses heavy therapeutic means which are often disproportionate to the expected benefit, namely keeping alive a patient whose condition is considered medically hopeless;and euthanasia which would precipitate the process of death would be sedation in the terminal phase of the illness. should doctors and families of comatose patients decide the “life” and “death” of their patients? For anti-euthanasia associations, doctors, relatives of terminally ill patients and the state itself, if they accept the principle of euthanasia, they are “murderers”, while for pro-euthanasists, the dignity of the human being would recommend that the days of patients in situations considered critical be shortened, to avoid unnecessary suffering and humiliation. Methods: A systematic review of the literature was carried out to identify relevant articles relating to euthanasia, dysthanasia and sedation in the terminal phase of illness. The search was conducted in French or English in three databases: PubMed, Google scholar and science Direct. Objectives: The objectives of this article are: 1) define the terminologies and concepts of palliative sedation, deep sedation, deep and continuous sedation until death, euthanasia and dysthanasia;2) present aspects of the meaning of life and the human person in African cultures;and 3) propose an ethical reflection on the value of life. Results: After precisely defining the concepts of euthanasia, dysthanasia and sedation, this research presented the African anthropological and ethical approach to the mysteries of life and death. Conclusion: With this in mind, the golden rule of medicine always remains as such “Primum non nocere”.

关键词： Euthanasia Dysthanasia End-Of-Life sedation Palliative Care African Cultures

Experimental and Numerical study of Energy Losses in a Barbecue Oven in Burkina Faso

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Open Journal of Energy Efficiency 2020年第1期9卷 31-52页

作者： gael Lassina sawadogo Laboratoire d’Energies Thermiques Renouvelables(LETRE) Universite Pr Joseph KI-ZERBOOuagadougouBurkina Faso Departement Energie Institut de Recherche en Sciences Appliquees et Technologies(IRSAT)OuagadougouBurkina Faso Laboratoire de Mathematiques et Physique(LAMPs) Universite de Perpignan Via Domitia(France)PerpignanFrance

This work concerns an experimental and numerical study of energy losses in a typical oven usually used in the agro-food craft sector in Burkina Faso. The experimental results were obtained by infrared thermography of the oven and by monitoring the evolution of the wall temperatures using thermocouples connected to a data acquisition system. These results indicate that the energy losses are mainly through the walls of the oven. The numerical study based on the energy balance and corroborated by the experimental study made it possible to quantify these losses of energy which represents almost half of the fuel used. These results will allow us to work on a new, more efficient oven model for the grilling sector in Burkina Faso.

关键词： Grill Oven Optimization Energy Losses Nodal Method