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Preliminary Palynostratigraphic Data on the middle Albian-Lower Cenomanian of the Tarfaya Basin, Southwest morocco

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Open Journal of Geology 2024年第4期14卷 548-568页

作者： Khaoula Chafai Touria Hssaida Wafaa maatouf mohamed Z. Yousfi Sara Chakir Soukaina Jaydawi Hanane Khaffou Department of Geology Faculty of Sciences Ben M&#8217Sik University Hassan II Casablanca Morocco Department of Petroleum Laboratory Office National des Hydrocarbures et des Mines Rabat Morocco Department of Geology Faculty of Sciences Dhar El Mahraz Sidi Mohamed Ben Abdellah University Fes Morocco Department of Geology Faculty of Sciences Mohammed V University Rabat Morocco

The Tarfaya-Laayoune-Boujdour basin is of great interest to oil exploration;on this aspect, there has been exploration by the moroccan National Office of Hydrocarbons and mining, which has shown indices of oil and/or gas recorded in most wells drilled in the moroccan Atlantic margin. FD-1 well, object of this study, is one of these wells located in the offshore Tarfaya-Laayoune-Boujdour basin. A palynological examination of the processed samples revealed the existence of organic palynomorphs, well conserved and rich in dinoflagellate cysts. The latter are composed of worldwide marker taxa of high stratigraphic resolutions. Thus, the middle upper Albian (3408 - 3408.5 m) is determined by the presence of Cribroperidinium tensiftense, Tehamadinium coummia, Spiniferella cornuta, Chichaouadinium vestitum, Dinopterygium alatum and Litosphaeridium arundum. The upper Albian (3406.5 - 3408 m) is characterized by the FOs of marker taxa: Cyclonephelium chabaca, Cribroperidinium auctificum and Chichaouadinium vestitum. Lastly, the upper Albian-lower Cenomanian transition is defined between 3404 m and 3406.50 m, as suggested by the FOs of Chichaouadinium boydii, Dinopterygium tuberculatum, Sepispinula ancorifera, Litosphaeridium conispinum, Prolixosphaeridium conulum and Xenascus ceratioides.

关键词： morocco Tarfaya-Laayoune-Boujdour Basin Albian-Cenomanian Transition Dinoflagellate Cysts Palynostratigraphy

Evaluation of the Level of Pollution by Heavy metals of market Garden Soils along the Chari River in Ndjamena: Case of the 9th and 7th Districts

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Agricultural sciences 2024年第8期15卷 939-961页

作者： Kotva Wana mackaye Hassane Taisso Likius Andossa Béral Djétenbé Laboratoire Gosciences Dpartement des Sciences de la Terre Facult des Sciences Universit de NDjamena NDjamena Chad Laboratoire Gosciences Dpartement des Sciences de la Terre Facult des Sciences Universit de Mongo Mongo Chad Laboratoire Sol et Environnement (LASEN) Dpartement des Sciences de la Terre Facult des Sciences Universit de Ngaoundr Ngaoundr Cameroun

The main aim of this study was to characterize the metal content of soils used for market gardening along the Chari river: the 7th and 9th districts of NDjaména. To achieve this, two sites were selected: Gassi and Walia, and two control sites (Gassi and Walia). A total of fifty (50) soil samples were taken (24 from the Gassi site, 24 from the Walia site and 2 as control soils) and then analyzed to determine a number of physico-chemical parameters (pH, Om and electrical conductivity) and heavy metal concentrations in the various soils. The TmE content (As, Cd, Cu, Cr, Ni, Pb, Hg and Zn) of the soils was determined by plasma-coupled Atomic Emission Spectrometry. In order to assess the level of contamination in Gassi and Walia soils, the geoaccumulation index (GeoIndex), contamination factor and degree of contamination were calculated. Results for physico-chemical parameters revealed that pH ranged from acidic (4.6) to moderately neutral (6.5), electrical conductivity was higher in cultivated soils (mean 292.14 μs/cm) than in control soils (mean 149.33 μs/cm), and soils were rich in organic matter. Overall, heavy metal concentrations in cultivated soils were higher than in control soils. The pollution estimate shows that soils in the area have no moderate contamination. The increase in TmE concentrations in cultivated soils is thought to be due to the input of agricultural inputs to the soil. However, these levels are below the Average shale reference and Canadian guidelines for agricultural soil quality. Principal component analysis shows that metals are positively and significantly correlated with each other, and negatively and moderately significantly correlated with each other.

关键词： Contamination Agricultural Soils City of N’Djaména ETm Gassi Walia

Land Use and Gully Dynamics in the Kourfa Watershed, matankari (Southwest Niger)

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Journal of Geographic Information System 2024年第4期16卷 306-320页

作者： Bachirou Hamadou Younoussa Tahirou Hassane Yaou Bouba Hassane Abass Kadade Sabou Abdoulkader moussa Issaka Amadou Abdourhamane Toure Zibo Garba facult des sciences et Techniques Universit de Dosso Dosso Niger facult des sciences et Techniques Universit Abdou Moumouni de Niamey Niamey Niger facult des sciences et Techniques Universit Andr Salifou de Zinder Zinder Niger

The main consequences of climate change in the Sahel have been the metamorphosis of surface conditions. These metamorphoses have resulted in surface degradation, of which silting up of watersheds is the main phenomenon. The objective of this study is to assess the environmental trends of the Kourfa pond watershed. The study is based on diachronic mapping with Landsat satellite images and Google Earth images, over the period 1986 to 2021. The study reveals that vegetation (whose rate of regression doubled between 1986 and 2021) has decreased to the benefit of crop areas (whose rate of increase multiplied by 3.61 between 1986 and 2021). Bare soil and encrusted areas have also decreased, with regression rates almost double than those of 1986. In addition, the Kourfa waterholes have experienced two types of changes over 35 years: one progressive between 2011 and 2016 and the other regressive between 2001 and 2021 compared to 1986. The ravine network has been multiplied by a factor of 2.4, with density more than doubled and the connectivity of the hydrographic networks has risen from 2 to 4, with significant bank recession. This dynamic of the Kourfa pond is linked to the high drainage, the increasing complexity of the gully network and the erosion due to the retreat of the watershed banks, all of which contribute to the silting-up of the Kourfa watershed.

关键词： Kourfa Pond Dynamics Watershed Dosso Niger

Black hole shadows in Einstein-Bel-Robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： B.Hamil B.C.Lütfüoğlu Laboratoire de Physique mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-Bel-Robinson (EBR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EBR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-Bel-Robinson gravity plasma

Trends of Land Use and Land Cover Change in the Savannah Ecological of the Protected Area Reserve Partielle de Dosso, Niger

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Natural Resources 2024年第3期15卷 61-68页

作者： Amadou Issoufou Abdourhimou moussa Boubacar Habou Rabiou Soumana Idrissa mahamane Ali faculté des sciences Agronomiques Université de Diffa Diffa Niger Institut National de la Recherche Agronomique du Niger Niamey Niger faculté des sciences et Techniques Université Abdou Moumouni de Niamey Niamey Niger

Information on the dynamics of savannah is important to a country's plan to overcome the problems of uncontrolled development and environmental hazards. Taking the reserve partielle de Dosso, Niger as the case study area, this paper analyzed the long-term land use land cover change from 2002 to 2022. Satellite images were processed by using Google Earth Engine (GEE). Therefore, four major land cover classes were identified based on spectral characteristics of Land sat, namely, built-up, vegetation, cropland, bare land and water. The result revealed that barren and built-up areas increased at the expense of vegetation and water. From the four major land use land cover the large area is covered by vegetation which comprises about 192963.5 hectares followed by cropland and water consisting of 32506.43 and 1596.4 hectares respectively. The built-up area gained substantial area (most) during the study period. The reduction in some of the land cover/uses underlines the dangerous trend of the pressure poised by population growth and the changing functionality. Land cover change is influenced by a variety of societal factors operating on several spatial and temporal levels. The area estimates and spatial distributions of the LULC classes produced from the current study will assist local authorities, managers, and other stakeholders in decision-making and planning regarding forest land cover and uses.

关键词： Land Use/Cover Change Detection Classification Dosso

A New multiobjective Particle Swarm Optimization Using Local Displacement and Local Guides

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Open Journal of Optimization 2024年第2期13卷 31-49页

作者： Saïd Charriffaini Rawhoudine Abdoulhafar Halassi Bacar Laboratoire des mathmatiques Statistiques Informatique et Applications (LMSIA) Dpartement des Mathmatiques Physique-Chimie et Informatique Facult des Sciences et Techniques Universit des Comores Moroni Comoros

This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SmPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors.

关键词： Particle Swarm Optimization multiobjective Optimization Attractor-Based Displacement Square Root Distance Crowding Distance

Primary Non-Hodgkin’s malignant Lymphoma of the Uterus at the Reference Hospital of maradi/Niger: A Case Report

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Open Journal of Blood Diseases 2024年第2期14卷 43-46页

作者： moustapha Elhadji-Chefou Badé malam-Abdou Amadou Djibrilla-Almoustapha maman Brah moustapha Oumou Kimso Ibrahim Timi Liman Elhadji Ali Issa Abdou Amadou Borges moreno Yuribet facult des sciences de la Sant Universit Dan Dicko Dankoulodo de Maradi Maradi Niger Hopital de Reference de maradi Maradi Niger facult des sciences de la Sant Universit Abdou Moumouni de Niamey Niamey Niger facult des sciences de la Sant Universit Andr Salifou de Zinder Zinder Niger

malignant non-Hodgkins lymphoma (mHNL) of the uterus is uncommon. We report a case diagnosed on the basis of histologic and immunohistochemical studies of a hysterectomy specimen induced by a very painful pelvic mass in a 50-year-old patient with no previous history of the disease. It was classified as Ann Arbor IV Bb after imaging, given the medullary infiltration and signs of clinical and biological evolutivity: the patient had received two courses of chemotherapy, CHOP protocol. She died 23 days after the second treatment due to a hypertensive crisis.

关键词： malignant Non-Hodgkin’s Lymphoma Uterus Referral Hospital maradi/Niger

Numerical Simulation of Dam-Break Flows Using Radial Basis Functions: Application to Urban Flood Inundation

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American Journal of Computational mathematics 2024年第3期14卷 318-332页

作者： Abdoulhafar Halassi Bacar Said Charriffaini Rawhoudine Laboratoire des mathmatiques Statistiques Informatique et Applications (LMSIA) Dpartement des Mathmatiques Physique-Chimie et Informatique (MPCI) Facult des Sciences et Techniques Universit des Comores Moroni Comoros

Dam-break flows pose significant threats to urban areas due to their potential for causing rapid and extensive flooding. Traditional numerical methods for simulating these events struggle with complex urban landscapes. This paper presents an alternative approach using Radial Basis Functions to simulate dam-break flows and their impact on urban flood inundation. The proposed method adapts a new strategy based on Particle Swarm Optimization for variable shape parameter selection on meshfree formulation to enhance the numerical stability and convergence of the simulation. The method’s accuracy and efficiency are demonstrated through numerical experiments, including well-known partial and circular dam-break problems and an idealized city with a single building, highlighting its potential as a valuable tool for urban flood risk management.

关键词： Dam-Break Flows Numerical Simulation Shallow Water Equations Radial Basis Functions Urban Flood Inundation

Influence of the Nature of the Incoming Sludge on the Performance of a Vertical Flow Reed Beds in Dakar-Senegal

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Journal of Water Resource and Protection 2024年第6期16卷 429-449页

作者： Elhadji mamadou Sonko Diomaye Dieng maïmouna Lo Cheikh Diop Laboratoire dEtude Environnemental des milieux Urbains (LEEmUR) Institut des Sciences de lEnvironnement (ISE) Facult des Sciences et Technique (FST) Universit Cheikh Anta Diop de Dakar (UCAD) Dakar-Fann Sngal

This work investigates the influence of the type sludge on drainage, plant development, purification performances and biosolids quality. Drainage properties were measured through the frequency of clogging, the percentage of leachate recovered and the dryness of accumulated sludge. Plant development was measured through the density, the height and the stem diameter. Purification performance was evaluated from the reduction rate. Biosolids quality was measured after 3 months of maturation. The results show that the clogging frequencies were 9.5%;0% and 3.7%;the volume of leachate recovered was 42.2%;20.4% and 24.7% and, the dryness was 33.4%;61.1% and 52.4% for FS-ST, FS-STT and SS respectively. Plants densities were about, with densities 197.1, 171.3 and 178.3 plants/m2 in beds fed respectively with FS-ST, FS-STT and SS. despite the high removal rates, the concentrations of pollutants in the leachates are above the Senegalese standard NS 05-061 for discharge into the environment. The biosolids are all mature with C/N and NH4+/NO3?ratios lower than 12 and 1 respectively. The biosolids are also rich in organic and mineral elements. The concentrations of Ascaris eggs are higher than the WHO recommendations. These biosolids should be stored for additional time or composted.

关键词： Biosolid Quality Dewatering Performance Planted Drying Beds Purification Performance Sludge Type