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Mobility of Major and Trace Elements during the Bauxitization Processes in Ngaoundal Area (Adamawa Cameroon): Implication on Mining Perspectives

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Open Journal of Geology 2024年第1期14卷 81-100页

作者： André Sini Harouna Boukari Ondoa Augustin Désiré Balla Djetenbe Beral salomon wangmené awé Simon Djakba Basga Jean Pierre Nguetnkam Department of Mining Engineering School of Geology and Mining Engineering University of Ngaoundere Ngaoundere Cameroon Department of Mining Engineering and Environment School of Mining Industry and Geology University of Abdou-Moumouni Niamey Niger Department of Earth Sciences Faculty of Science University of Ngaoundere Ngaoundere Cameroon Department of Mining Engineering Saint Jerome Polytechnic Saint Jerome Catholic University Institute of Douala Douala Cameroon Institute of Agricultural Research for Development (IRAD) Garoua Cameroon

This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al2O3 mainly in the scoriaceous facies (over 45% in grade), moderate in Fe2O3 (averaging 23.69%) and SiO2 (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and V (213 ppm on average). In addition, the limited quantities of alkalis (Na2O, K2O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized.

关键词： Duricrust Bauxitization Phenomenon Mineralogical and Geochemical Characterization Major and Trace Elements Mining Potential

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Evaluation of Four Anthropogenic Activity Impacts on Heavy Metal Quality of the Kumba River in the South West Region of Cameroon

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Journal of Water Resource and Protection 2024年第5期16卷 361-380页

作者： Martin Keghe Nkobe Barthelemy Ndongo Kanouo Boris Merlain Djousse salomon Nyasse Institute of Agricultural Research for Development (IRAD) Yaound&#233 Cameroon Faculty of Agronomy and Agricultural Sciences (FASA) University of Dschang Dschang Cameroon

Anthropogenic activities have contributed to pollution of water bodies through deposition of diverse pollutants amongst which are heavy metals. These pollutants, which at times are above the maximum concentration levels recommended, are detrimental to the quality of the water, soil and crops (plant) with subsequent human health risks. The objective of the work was to evaluate the impacts of human-based activities on the heavy metal properties of surface water with focus on the Kumba River basin. Field observations, interviews, field measurements and laboratory analyses of different water samples enabled us to collect the different data. The results show four main human-based activities within the river basin (agriculture, livestock production, domestic waste disposal and carwash activities) that pollute surface water. Approximately 20.61 tons of nitrogen and phosphorus from agricultural activities, 156.48 tons of animal wastes, 2517.5 tons of domestic wastes and 1.52 tons of detergent from carwash activities were deposited into the river each year. A highly significant difference at 1% was observed between the upstream and downstream heavy metal loads in four of the five heavy metals tested except for copper that was not significant. Lead concentrations were highest in all the activities with an average of 2.4 mg∙L−1 representing 57.81%, followed by zinc with 1.596 mg∙L−1 (38.45%) and manganese with 0.155 mg∙L−1 (3.74%) for the different anthropogenic activities thus indicating that these activities highly lead to pollution of the Kumba River water. The level of zinc and manganese was significantly influenced at ρ 005 by anthropogenic activities though generally the variations were in the order: carwash (3.196 mg∙L−1) −1) −1) −1) r

关键词： Metal Properties Human-Based Activities Kumba River Basin Surface Water

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A systematic review of cytoreductive prostatectomy outcomes and complications in oligometastatic disease

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Asian Journal of Urology 2024年第2期11卷 208-220页

作者： Andrey Morozov Leonid Chuvalov Mark Taratkin Mikhail Enikeev Leonid Rapoport Nirmish Singla Eric Barret Elena Poddubskaya Maria Borodina Georg salomon Juan Gomez Rivas Dmitry Enikeev Institute for Urology and Reproductive Health Sechenov UniversityMoscowRussia Young Academic Urologists EAUthe Netherlands Department of Urology James Buchanan Brady Urological InstituteThe Johns Hopkins University School of MedicineBaltimoreUSA Department of Urology Institut Mutualiste MontsourisParisFrance Sechenov University MoscowRussia Hertsen Moscow Oncology Research InstituteMoscowRussia Hertsen Moscow Oncology Research Institute MoscowRussia Martini Clinic University Medical Center Hamburg-EppendorfHamburgGermany Department of Urology Clinico San Carlos University HospitalMadridSpain Department of Urology Medical University of ViennaViennaAustria

Objective: To analyze outcomes and complications of cytoreductive prostatectomy (CRP) for oligometastatic prostate cancer (PCa) in order to elucidate its role in this ***: We performed a systematic literature search using three databases (Medline, Scopus, and Web of Science). The primary endpoints were oncologic outcomes. The secondary endpoints were complication rates and functional ***: In all studies, overall survival was better or at least comparable variable in the groups with CRP compared to no local treatment. The greatest benefit from CRP in 5-year overall survival in one study was 67.4% for CRP versus 22.5% for no local treatment. Cancer-specific survival (CSS) showed the same trend. Several authors found significant benefits from CSS in the CRP group: from 79% vs. 46% to 100% vs. 61%. CRP was a predictor of better CSS (hazard ratio 0.264, p=0.004). Positive surgical margin rates differed widely from 28.6% to 100.0%. Urinary continence in CRP versus RP for localized PCa was significantly lower (57.4% vs. 90.8%, p<0.0001). Severe incontinence occurred seldom (2.5%-18.6%). Total complication rates after CRP differed widely, from 7.0% to 43.6%. Rates of grades 1 and 2 events prevailed. Patients on ADT alone also showed a considerable number of complications varying from 5.9% to 57.7%.Conclusion: CRP improves medium-term cancer control in patients with oligometastatic PCa. The morbidity and complication rates of this surgery are comparable with other approaches, but postoperative incontinence rate is higher compared with RP for localized disease.

关键词： Systematicreview Prostatecancer Oligometastatic Bone metastases Cytoreductive prostatectomy

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Quantification of Total Phenols, Total Flavonoids, Total Anthocyanins and Evaluation of Antioxidant and Antiradical Activities of Detarium Senegalense Extracts from Chad

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Advances in Biological Chemistry 2024年第1期14卷 1-15页

作者： salomon Madjitoloum Betoloum Séverin Mbaihougadobe Abel Mbaiogaou Djibrine Adoum Oumar Mbaindiguim Dagoto Yaya Mahmout Laboratory of Research on Natural Substances Faculty of Exact and Applied Sciences (F.E.A.S) University of N’Djamena N’Djamena Chad Department of Chemistry University of Moundou Moundou Chad

The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity of Detarium Senegalense extracts. For this purpose, sequential extraction using solvents of increasing polarity was essential. The various extracts obtained underwent phytochemical and biochemical analyses. Phytochemical screening revealed the presence of flavonoids, alkaloids, tannins, polyphenols, anthocyanins and steroids/terpenes. Quantitative analysis of total polyphenols, total flavonoids and total anthocyanins yielded the following results: total flavonoids (0.803 ± 0029 mg EQ/100g P for acetone extract of roots and 0.871 ± 0.401 mg EQ/100g P for methanol extract of leaves);total polyphenols (23.298 ± 12.68 mg EAG/100g P for acetone extract of roots and 24.69 ± 0.49 401 mg EAG/100g P for methanol extract of leaves);total monomeric anthocyanins (44.697 ± 0.939 mg EC3G/100g P and 16.699 ± 0.193 mg EC3G/100g P respectively for acetone and methanol extracts of stem bark). DPPH free radical scavenging activity was 1.674 ± 0.023 mg/mL for the acetone extract and 0.934 ± 0.24 mg/mL for the methanol extract of roots. .

关键词： Total Phenols Total Flavonoids Total Anthocyanins Antioxidant and Anti-Radical Activities Detarium Senegalense Chad

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Effect of Artemisia annua (Asteraceae) Extracts on Hemolysis in Individuals with G6PD-Deficiency

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Journal of Biosciences and Medicines 2024年第3期12卷 303-315页

作者： Jescica Bonarck Sohou Casimir Jiras Kpego Ligan salomon Ezechiel Mahougnon Fiogbe Thierry Comlan Marc Medehouenou Fifame Esperance Elvire Kougnimon Casimir Dewanou Akpovi Unité de Recherche sur les Maladies Non Transmissibles et le Cancer (UR-MNTC) Laboratoire de Recherche en Biologie Appliquée Ecole Polytechnique d’Abomey-Calavi University of Abomey-Calavi Cotonou Benin

Individuals with Glucose-6-phosphate dehydrogenase (G6PD) deficiency are susceptible to hemolytic anemia when exposed to pro-oxidant substances. This study investigates the hemolytic impact of Artemisia annua (A. annua) extracts in G6PD-deficient subjects through a mixed experimental approach. In the in vitro phase, red blood cells from G6PD-deficient individuals and rats induced with Dehydroepiandrosterone (DHEA) were exposed to various concentrations of A. annua infusion, with distilled water and physiological saline as positive and negative controls respectively. The in vivo study involved G6PD-deficient Wistar rats divided into three groups receiving A. annua infusion, quinine (positive control), and distilled water (negative control) via gavage. Blood samples were collected for biochemical and hematological analyses. Notably, at a 40% concentration of A. annua infusion, there was a significant increase in the hemolysis rate of G6PD-deficient red blood cells compared to controls (p A. annua exhibited elevated aspartate aminotransferase (129.25 ± 4.55 U/L vs. 80.09 ± 4.03 U/L;p A. annua infusion tested positive for saponins. These findings underscore the risk of hemolysis in G6PD-deficient individuals upon ingesting A. annua.

关键词： Artemisia annua Infusion Saponins G6PD Deficiency Hemolysis

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Ethnobotanical and Phytochemical Study of Medicinal Plants Sold in the Markets of the City of N’Djamena

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Advances in Biological Chemistry 2024年第4期14卷 121-144页

作者： Djibrine Adoum Oumar Teissir Ibrahim Abakar Hama Cissé salomon Madjitoloum Betoloum Adama Sawadogo Jean-Ulrich Muandze Nzambe Elisée Mbayngone Abdelsalam Tidjani Aly Savadogo Natural Substances Research Laboratory (NSRL) Faculty of Exact and Applied Sciences (FEAS) University of NDjamena Chad Tchad Laboratory of Applied Biochemistry and Immunology (LABI) Joseph KI-ZERBO University Ouagadougou Burkina Faso Food Science and Nutrition Research Laboratory (FSNRL) Faculty of Human Health Sciences (FHHS) University of NDjamena Chad Tchad

The use of medicinal plants occupies an important place in traditional Chadian medicine, this study was carried out with the aim of listing the medicinal plants sold in the markets of the city of N’Djamena, and knowledge of the medicinal flora Chad, such as the leaves of Guiera senegalensis in Arabic called Khibeche, the roots of Cassia occidentalis called Am kwala-Kinkéliba in Arabic;the bark of Khaya senegalensis (Desv) A. Juss called Muraї in Arabic and the seeds of Trigonella foenum-graecum called Helbé in Arabic in order to treat the most frequently cited diseases such as malaria, the common cold, mother and newborn care, and typhoid. Ethnobotanical surveys were conducted from September to December 2022, in three markets in the city of N’Djamena, based on individual interviews using a semi-structured questionnaire, with 30 herbalists and traditional practitioners. Phytochemical screening analyses of the organs of four plants were carried out in the chemistry and biology laboratory of the Faculty of Exact and Applied Sciences (FSEA) following a standard protocol established by [1] and slightly modified by [2] [3]. The results of the surveys identified 68 species divided into fifty-five (55) genera and twenty-seven (27) families, the most represented of which were Caesalpiniaceae (10 species), Mimosaceae (5 species) and Combretaceae (4 species). The leaves were the most commonly used parts (43%), with decoction (70%) the most frequently used method of preparation. The oral route was the most popular with 73% of recipes. The phytochemical study revealed a wealth of secondary metabolites such as Trapezoidal Sterols, Alkaloids, Tannins, Flavonoids, Free Quinones, Anthocyane, Anthraquinones, Saponosides and Heterosides. These results can be considered as a source of information for scientific research in the field of phytochemistry and pharmacology.

关键词： Chad (N’Djamena) Medicinal Plants Ethnobotany Screening Phytochemistry

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Finite element modelling of the geodynamic processes of the Central Andes subduction zone:A Reference Model

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Geodesy and Geodynamics 2018年第3期9卷 246-251页

作者： Chris salomon Institute of Geosciences General Geophysics and Structural Geology Group Friedrich Schiller University

This paper presents preliminary results of three-dimensional thermomechanical finite-element models of a parameter study to compute the current temperature and stress distribution in the subduction zone of the central Andes （16°S-26°S） up to a depth of 400 km, the bottom of the asthenosphere. For this purpose a simulation running over c. 50,000 years will be realized based on the geometry of a generic subduction zone and an elasto-viscoplastic Drucker-Prager rheology. The kinematic and thermal boundary conditions as well as the rheological parameters represent the current state of the study area. In future works the model will be refined using a systematic study of physical parameters in order to estimate the influence of the main parameters （e.g. viscosity, fault friction, velocity, shear heating） on the results of the reference model presented here. The reference model is kept as simple as possible to be able to estimate the influence of the parameters in future studies in the best possible way, whilst minimizing comnutational time.

关键词： Abaqus Andes subduction zone Finite element modelling Thermomechanical models Viscoplasticity

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Lupus enteritis as the only active manifestation of systemic lupus erythematosus: A case report

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World Journal of Clinical Cases 2019年第11期7卷 1315-1322页

作者： Adalberto Gonzalez Vaibhav Wadhwa Fayssa salomon Jeevna Kaur Fernando J Castro Department of Internal Medicine Cleveland Clinic Florida Weston FL 33331 United States Department of Gastroenterology and Hepatology Cleveland Clinic Florida Weston FL 33331 United States

BACKGROUND Lupus enteritis is a rare manifestation of systemic lupus erythematosus (SLE). Diagnosis of this condition is difficult, especially in the absence of other symptoms related to active SLE. We present the case of a 25-year-old female with lupus enteritis as the sole initial manifestation of active SLE. CASE SUMMARY A 25-year-old African American female presented to the Emergency Department complaining of diffuse abdominal pain, diarrhea, nausea, and vomiting for 2 days. Her past medical history was significant for seasonal allergies and family history was pertinent for discoid lupus in her father and SLE in a cousin. The patient’s vital signs on presentation were normal. Her physical exam was remarkable for significant lower abdominal tenderness without guarding or rigidity. A computed tomography of the abdomen and pelvis revealed marked circumferential wall thickening and edema of the proximal and mid small bowel predominantly involving the submucosa. Our main differential diagnoses were intestinal angioedema and mesenteric vein thrombosis. However, mesenteric vessels were patent, and laboratory testing for hereditary angioedema showed a normal C1 Esterase Inhibitor level and low C3 and C4 levels. Infectious work-up was negative. Autoimmune tests showed elevated anti-nuclear antibodies (ANA)(13.6), anti-Smith antibody, and anti-ribonucleoprotein (anti-RNP) antibody. The patient was diagnosed with SLE enteritis. She was maintained on bowel rest, given intravenous hydration, and started on methylprednisolone 60 mg IV daily. She had significant improvement in her abdominal pain, diarrhea, and emesis after 2 days of treatment. Steroids were tapered and maintained on Hydroxychloroquine with no relapses one year after *** This case of lupus enteritis represents a rare manifestation of SLE. Diagnosis requires clinical suspicion, characteristic imaging and laboratory tests. Endoscopic appearance and biopsies usually yield non-specific findings.

关键词： Lupus enteritis Systemic lupus erythematous Abdominal pain Hereditary angioedema Case report

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Factors Leading to the Learning Crisis in Public Secondary Schools in Benin:A Case Study

Factors Leading to the Learning Crisis in Public Secondary S...

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作者： Ogoubiyi Folabi Arthur salomon 浙江师范大学

学位级别：硕士

This research study aimed at investigating the factors leading to learning crisis in Krake and Tohoue public secondary schools in Tohoue district,Benin and the strategies used by Krake public secondary school to mitigate the *** study was guided by the following research objectives: to determine the factors responsible for learning crisis in public secondary schools in Tohoue district Benin,to determine how these factors can affect the learners and to explore the approaches or strategies of mitigating learning crisis of public secondary schools in *** researcher used descriptive research *** two public secondary schools of Tohoue district were targeted and were mainly the focus of this *** convenience and purposeful sampling techniques were *** research instruments were used in collecting data,namely: a document analysis guide,questionnaire guide and *** were transcribed,summarized,categorized and interpreted *** from participants and data which were obtained from different documents were *** and patterns in the responses were ***,direct quotations,interpretive reports as well as excerpts were written down to depict the situation as it was on the *** the data analysis,the following findings were made: inappropriate education system pillared on the competency based approach which seemed to be unproductive,parent’s ignorance mainly due to lack of education which seemed to be obstructing the students learning,the high rate of untrained teachers in public secondary schools which proved to be ineffective and lastly the school leadership looked either positive or negative which could influence the learning performances of the *** order to contribute effectively to the problem of the learning crisis in public secondary schools in Benin,the following recommendations were made: Relevant learning materials that reflect relevant skills,knowledge,attitudes,and va

关键词： Learning Crisis Public Secondary Schools Factor analysis Benin

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Neural Network Based Diagnostics of Actuator for an Attitude Control System

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Computer Aided Drafting,Design and Manufacturing 2010年第2期20卷 59-67页

作者： salomon Montenegro School of Astronautics Beijing University of Aeronautics and Astronautics

The objective of this paper is to develop a neural network-based residual generator to detect the fault in the actuators for a specific communication satellite in its attitude control system （ACS）. First, a dynamic multilayer perceptron network with dynamic neurons is used, these neurons correspond to a second order linear Infinite Impulse Response （IIR） filter and a nonlinear activation function with adjustable parameters. Second, the parameters from the network are adjusted to minimize a performance index specified by the output estimated error, with the given input-output data collected from the specific ACS. Then, the proposed dynamic neural network is trained and applied for detecting the faults injected to the wheel, which is the main actuator in the normal mode for the communication satellite. Then the performance and capabilities of the proposed network were tested and compared with a conventional model-based observer residual, showing the differences between these two methods, and indicating the benefit of the proposed algorithm to know the real status of the momentum wheel. Finally, the application of the methods in a satellite ground station is discussed.

关键词： satellite attitude control momentum wheel neural network fault detection

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