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Journal of Power and Energy Engineering 2020年第7期8卷 1-14页

作者： théodore patrice nna nna Salomé Ndjakomo Essiane Stève Pérabi Ngoffé Technology and Applied Sciences Laboratory University of Douala Douala Cameroon

this paper presents the control of the active filter by Duty Cycle Modulation (DCM) for the harmonic pollution control of a three-phase electrical system. Several research works have preceded this work, but most of them deal with the control by pulse-width modulation and the differences lie around the thD reduction performance, the quality of the wave obtained, the simplicity of the scheme and the cost of the control. For this purpose, we propose a very innovative approach to active filter control which aims at reducing the current thD at a lower rate than pulse-width modulation techniques improving at the same time the wave quality with a more simplified control scheme. First we present the schematic diagram of the active filter, then we present the design of the control of this active filter based on the real and imaginary instantaneous power method which uses the algebraic “Clark” transformation. the Duty Cycle Modulation controller is used to obtain the required control commands to be injected to the inverter. We then developed a simulink model of the active filter to validate this study. the simulations were performed in the Matlab/Simulink environment. the results obtained show a significant improvement on the harmonic current control techniques for the thD of 1.02% which was 26.25%, the elimination of noise in the signal and the simplicity of the control with an easier implementation than the pulse width modulation (PWM) make the Duty Cycle Modulation (DCM) control a very promising tool.

关键词： PWM DCM Active Filter Inverter

Marine invasions enter the genomic era： three lessons from the past, and the way forward

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Current Zoology 2016年第6期62卷 629-642页

作者： Frederique VIARD patrice DAVID John A. DARLING Sorbonne Universites UPMC Univ Paris 06 CNRS UMR 7144 Lab. Adaptation Et Diversite En Milieu Marin Team Div&Co Station Biologique De Roscoff Roscoff 29682 France CEFE UMR 5175 CNRS-Universite De Montpellier- UM III-EPFIE 1919 Route De Mende Montpellier Cedex 34293 France National Exposure Research Laboratory United States Environmental Protection Agency Research Triangle Park NC 27711 USA

the expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species （NIS） also have attracted much attention as opportunities to explore important eco-evolutionary processes such as rapid adaptation, long-distance dispersal and range expansion, and secondary contacts between divergent evolutionary lineages. In this context, genetic tools have been extensively used in the past 20 years. three important issues appear to have emerged from such studies. First, the study of NIS has revealed unexpected cryptic diversity in what had previously been assumed homogeneous entities. Second, there has been surprisingly little evidence of strong founder events accompanying marine introductions, a pattern possibly driven by large propagule loads. third, the evolutionary processes leading to successful invasion have been difficult to ascertain due to faint genetic signals. Here we explore the potential of novel tools associated with high-throughput sequencing （HTS） to address these still pressing issues. Dramatic increase in the number of loci accessible via HTS has the potential to radically increase the power of analyses aimed at species delineation, exploring the population genomic consequences of range expansions, and examining evolutionary processes such as admixture, introgression, and adaptation. Nevertheless, the value of this new wealth of genomic data will ultimately depend on the ability to couple it with expanded ＂traditional＂ efforts, including exhaustive sampling of marine populations over large geographic scales, integrated taxonomic analyses, and population level exploration of quantitative trait differentiation through common-garden and other laboratory experiments.

关键词： biological invasions cryptic species cryptogenic species eco-evolutionary processes genornics metabarcoding

Geochemical,mineralogical and sedimentological analyses of reworked sediments(new)in the syn-to post-rift Middle Cretaceous-Quaternary detrital deposits from western Atlantic margin of Cameroon:evidence from sedimentation-erosion alternation in the cont

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Acta Geochimica 2021年第5期40卷 676-701页

作者： Milan Stafford Tchouatcha Arnaud patrice Kouske Amr Said Deaf Arthur Paterne Mioumnde Department of Earth Sciences University of DschangP.O.Box 67DschangCameroon Higher Institute of Chemistry and Management P.O.Box 4789YaoundeCameroon University Institute of Technology University of DoualaP.O.Box 8698DoualaCameroon Department of Geology Faculty of ScienceAssiut UniversityAsyut 71516Egypt Institute for Geological and Mining Research B.P.4110Yaounde´Cameroon

Reworked detrital sediments were discovered in the syn-rift to post-rift Cretaceous to Quaternary(Pleistocene)detrital deposits of the Douala coastal sub-basin in the eastern margin of the South Atlantic Ocean at West *** contribution presents the geochemical,mineralogical,and sedimentological data to constrain the origin of these reworked *** investigated samples are characterized by the high values of Plagioclase Index of Alteration(PIA,97.83–99.90),Chemical Index of Alteration(CIA,71.9–99.08),and Chemical Index of Weathering(CIW,98.67–99.90).Data gleaned from these indices suggest that the reworked sediments and their potential source rocks experienced severe *** A-CN-K plot along with the mineralogical indicates a probably post-depositional *** high light rare earth elements(LREE)/heavy rare earth elements(HREE)ratios(15.82–79.13)suggest that the reworked were mainly derived from felsic igneous *** interpretation is further confirmed by the Zr versus TiO2,TiO2/Al2O3,th/Co versus La/Sc,and La/th versus th/Yb plots,which indicate felsic igneous and silicic source ***,the high variability of LREE/HREE ratios(15.82–79.13)and the positive Eu anomalies(1.10–1.32)of studied samples could indicate a little contribution of mafic source *** of the distribution of the heavy minerals(***,aluminum silicate,and rutile)revealed that these felsic and silicic source rocks are mainly granite and gneiss,probably belonging to the Nyong Group and the Western part of the Neoproterozoic Yaounde *** morphoscopic analyses of the host rocks(very angular to angular shapes)have revealed that the reworked sediments have proximal to subproximal onshore origins,probably from former sedimentary deposits,as is indicated by variation of their *** tectonic discriminant diagram indicates the Oceanic Island Arc and Active Continental Margin which are inconsistent with the geological history of the Doual

关键词： Reworked sediments Geochemistry Mineralogy Sedimentology Nyong and yaoundégroups Douala coastal sub-basin Cameroon

Immune precision medicine for cancer:a novel insight based on the efficiency of immune effector cells

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Cancer Communications 2019年第1期39卷 318-333页

作者： Jean-François Rossi patrice Céballos Zhao-Yang Lu Institut Sainte Catherine 84918 AvignonFrance UniversitéMontpellier 1 UFR Médecine34396 MontpellierFrance Département d’Hématologie CHU de Montpellier34295 MontpellierFrance Unitéde thérapie Cellulaire CHU Saint-Eloi34295 MontpellierFrance

Cancer cell growth is associated with immune surveillance ***,restoring the desired immune response against cancer cells remains a major therapeutic *** to the recent advances in biological knowledge,efficient therapeutic tools have been developed to support the best bio-clinical approaches for immune precision *** of the most important successes in immune therapy is represented by the applicational use of monoclonal antibodies,particularly the use of rituximab for B-cell lymphoproliferative *** recently,other monoclonal antibodies have been developed,to inhibit immune checkpoints within the tumor microenvironment that limit immune suppression,or to enhance some immune functions with immune adjuvants through different targets such as Toll-receptor *** aim is to inhibit cancer proliferation by the diminishing/elimination of cancer residual cells and clinically improving the response duration with no or few adverse *** effect is supported by enhancing the number,functions,and activity of the immune effector cells,including the natural killer(NK)lymphocytes,NKT-lymphocytes,γδT-lymphocytes,cytotoxic T-lymphocytes,directly or indirectly through vaccines particularly with neoantigens,and by lowering the functions of the immune suppressive *** these new therapeutics and their personalized usage,new considerations have to be taken into account,such as epigenetic regulation particularly from microbiota,evaluation of transversal functions,particularly cellular metabolism,and consideration to the clinical consequences at the body *** aim of this review is to discuss some practical aspects of immune therapy,giving to clinicians the concept of immune effector cells balancing between control and *** precision medicine is a combination of modern biological knowledge and clinical therapeutic decisions in a global vision of the patient.

关键词： Precision therapy Immunotherapy NK lymphocytes T-lymphocytes Dendritic cells Vaccination Cancer

Provenance, depositional process, and tectonic setting of gold placer from the Bétaré-Oya Gold District(East-Cameroon, Central Africa)along the Precambrian Sanaga fault

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International Journal of Sediment Research 2023年第4期38卷 576-596页

作者： Milan Stafford Tchouatcha Arnaud patrice Kouske Primus Azinwi Tamfuh Epimarc Gildas Tchameni Ngouabe Gerald Chuye Yango Department of Earth Sciences Faculty of Science University of Dschang University Institute of Technology University of Douala Department of Mining and Mineral Engineering National Higher Polytechnic Institute University of Bamenda Department of Soil Science Faculty of Agronomy and Agricultural Sciences University of Dschang Department of Mining and Geology School of Geology and Mining Engineering University of Ngaoundere

the Bétaré-Oya Gold District is one of the three gold districts in East Cameroon with varied types of mining. the study site is an open-cast mine located in an alluvial plain. the strata succession globally consists of two positive sequences represented by three facies associations and seven lithofacies: massive clast-supported(Gcm), massive trough-cross bedded(Gtm), and massive matrix-supported(Gmm)conglomerates; massive sands(Sm); and massive(Fm), heterolothic(Fhl), and convolute and heterolithic(Fhlc) clays. the facies analysis indicates deposition after a recent tectonic event creating a depression,followed by a rapid deposition of varied facies and energies of sedimentation with fluvial and gravity inputs. the deposits come from proximal to distal sources but more proximal. the identified heavy mineral or accompanying minerals reveal a plutonic source(tourmaline sometimes folded), a volcanic source(olivine or clino-pyroxene with cracks), and a metamorphic source(sillimanite, andalusite, and staurolite). In the pan concentrates of placer with high silver(Ag) concentration(100 ppm) are also associated with relative abundance of lead(Pb)(17.8 ppm), zinc(Zn)(27 ppm), and low levels of copper(Cu)(3.1 ppm). the concentration and distribution of some element ratios, such as thorium/scandium(th/Sc), chromium/thorium(Cr/th), and europium anomaly(Eu/Eu*), rare earth elements(REEs) and aluminum oxide/titanium dioxide(Al2O3/TiO2) vs. silicon dioxide(SiO2) plots for the studied sediment indicate heterogeneous sources of rocks with dominance of felsic sources. the discriminant diagram reveals a recycled or sedimentary provenance of the deposited sediments. the tectonic setting plot indicates a collision tectonic setting which is consistent with the Precambrian history of the study area which belongs to the Pan-African North-Equatorial fold Belt. the gold deposits in the B etar e-Oya area probably derive from several sources, such as a vein source(from magmatic and metamorphi

关键词： Provenance Gold placer Sedimentology Geochemistry B etar e-Oya Cameroon

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Valuable Visits

ChinAfrica 2023年第9期15卷 56-57页

作者： patrice MONKAM Tsinghua University

the year 2023 marks the 10th anniversary of the Belt and Road Initiative(BRI),which was proposed by Chinese President Xi Jinping in two important speeches in *** BRI is a robust socioeconomic development strategy that seeks to enhance cooperation,exchanges and connectivity between China and other parts of the world,including Asia,Europe,Africa and Americas.

关键词： connectivity anniversary exchanges

Development and validation of a thermally regulated atmospheric simulation chamber(thALAMOS): A versatile tool to simulate atmospheric processes

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Journal of Environmental Sciences 2020年第9期32卷 141-154页

作者： Noureddin Osseiran Manolis N.Romanias Vincent Gaudion Maria E.Angelaki Vassileios C.Papadimitriou Alexandre Tomas patrice Coddeville Frederic thevenet IMT Lille Douai Univ.LilleSAGELille F-59000France Laboratory of photochemistry and chemical kinetics(LAPKIN) University of CreteHeraklion 71003CreteGreece

Atmospheric simulation chambers,are unique tools for investigating atmospheric processes in the gas and heterogeneous *** can provide a controlled yet realistic environment that simulates atmospheric *** the current study,a Teflon atmospheric simulation chamber of 600 L,named thALAMOS(thermally regulated atmospheric simulation chamber) has been developed and *** can be operated over the temperature range 233 to 373 K under both static and flow *** is equipped with state of the art instrumentation(selective ion flow tube mass spectrometry(SIFT-MS),long path Fourier transform infrared spectroscopy(FTIR),gas chromatography-mass spectrometry(GC-MS),various analyzers) for the in-line monitoring of both reactants and *** was validated by measuring the rate coefficients of well documented reactions,*** reaction of ethanol with OH radicals and the reaction of dichloromethane with Cl atoms,in a wide temperature *** different detection techniques were used in parallel,FTIR and SIFT-MS,to internally cross-validate the obtained *** measured rate coefficients are in excellent agreement,both between each other and with the literature recommended ***,the gas phase oxidation of toluene by Cl atoms(kinetics and product yields) was studied in the temperature range of 253 to 333 *** the best of our knowledge,thALAMOS is a unique facility on national level and among a few smog chambers internationally that can be operated in such a wide temperature range providing the scientific community with a versatile tool to simulate both outdoor and indoor physicochemical processes.

关键词： versatile equipped kinetics

High-Level Circulating Total Calcium and Low Phosphate as Predictors of Insulin Resistance among Non-Diabetic Taxi-Motorbike Drivers Living and Working in Cotonou, Benin

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Open Journal of Endocrine and Metabolic Diseases 2022年第6期12卷 123-134页

作者： patrice Hodonou Avogbe Ambaliou Sanni Laboratory of Biochemistry and Molecular Biology Department of Biochemistry and Cellular Biology University of Abomey-Calavi Cotonou Republic of Benin

Insulin resistance (IR) is a well-recognized marker of increased cardiovascular diseases (CVDs) and type 2 diabetes (T2D) risk. therefore, screening for IR predictors would help reduce the likelihood of progression from early stage of IR to T2D or CVDs. However, the knowledge of association between IR and circulating total calcium (CTCa) and phosphate levels among non-diabetic patients in Benin is lacking. We investigated whether CTCa and phosphate levels within the normal ranges are associated with IR risk among taxi-motorbike drivers (TMDs) living and working in Cotonou. We evaluated 134 non-diabetic TMDs (aged 22 - 59 years) based on CTCa, phosphate, glucose, fasting insulin, and IR levels. IR was assessed using the homeostatic model assessment-insulin resistance (HOMA-IR). IR was defined as the 75th percentile of HOMA-IR value. Cardiometabolic factors were analyzed by tertiles of CTCa and phosphate levels (low, middle, and high groups). Logistic regression models evaluated the relationships between IR and CTCa and phosphate levels. Our results showed that participants with high CTCa levels had the highest prevalence of IR, elevated total cholesterol and high-density lipoprotein cholesterol. In a fully adjusted model, the odd ratio (OR) of having IR comparing the highest (>2.50 mmol/L) to the lowest CTCa levels (1.23 mmol/L) and the lowest levels (that elevated CTCa and low phosphate levels are significant predictors of IR in non-diabetic patients. Continuous monitoring of these markers may help identify earlier individuals at greatest IR risk.

关键词： Blood Glucose Insulin Resistance Circulating Total Calcium Phosphate Taxi-Motorbike Drivers

Elevated White Blood Cell Count Is Associated with an Increased Risk of Insulin Resistance among Non-Diabetic Taxi-Motorbike Drivers Working in Cotonou, Benin

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Journal of Biosciences and Medicines 2022年第8期10卷 68-81页

作者： patrice Hodonou Avogbe Ambaliou Sanni Laboratory of Biochemistry and Molecular Biology Department of Biochemistry and Cellular Biology University of Abomey-Calavi Cotonou Benin

High white blood cell count (WBC) and insulin resistance (IR) are interrelated events that contribute to non-communicable diseases (NCDs), including type-2 diabetes (T2D). However, associations between IR and hematological parameters have never been explored in populations of Benin. the aims of this study were to determine the prevalence of IR and associated hematological parameters in taxi-motorbike drivers (TMDs) working in Cotonou. A total of 133 participants were analyzed in this cross-sectional study. Complete blood count, including WBC and platelet, as well as fasting plasma glucose and insulin, were performed by standard procedures. IR was assessed using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Factors associated with IR, their odds ratios (ORs) and 95% confidence intervals (CIs) were determined by logistic regression analysis. the mean age of the study participants was 39.3 years. the HOMA-IR cut-off (75th percentile) for IR was 5.9. the overall prevalence of IR was 24.1%. IR increased with the increase of exposure duration and WBC levels. Logistic regression analysis revealed that the risk of IR increased significantly with higher total WBC, with adjusted ORs (95% CI) for the second and third tertiles of 3.56 (1.10 - 11.58) and 4.01 (1.21 - 13.31), respectively. Similar patterns of associations were observed in an analysis restricted to non-drinkers, although these estimates lacked statistical significance. BMI > 24.2 kg/m2 was independently associated with an increased risk of IR (OR = 3.82, 95% CI: 1.33 - 11.03, P = 0.013). In conclusion, the prevalence of IR in TMDs was 24.1%. IR was significantly associated with elevated WBC count and BMI. WBC may serve as a biomarker to identify individuals at the greatest IR risk.

关键词： Cotonou Insulin Resistance Taxi-Motorbike Drivers White Blood Cells

Higher Plasma Potassium Level Reduces 10-Year Cardiovascular Disease Risk Predicted by the Framingham Risk Score among Taxi-Motorbike Drivers Residing and Working in Cotonou, Benin

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Journal of Biosciences and Medicines 2023年第4期11卷 417-430页

作者： patrice Hodonou Avogbe Ambaliou Sanni Laboratory of Biochemistry and Molecular Biology Department of Biochemistry and Cellular Biology University of Abomey-Calavi Cotonou Republic of Benin

Hypertension, obesity, smoking, dyslipidemia, and type 2 diabetes (T2D) are the major risk factors for developing cardiovascular diseases (CVD). Recent studies revealed that taxi-motorbike drivers (TMDs) in Cotonou had higher rates of CVD risk factors, but their impacts on cardiovascular events have rarely been studied. the Framingham risk score (FRS) is an algorithm that considers CVD risk factors and estimates the risk of developing CVD in the next 10 years. Our objectives were to assess the 10-year CVD risk predicted by the FRS, and to examine the relationships of 10-year CVD risk with plasma iron and potassium levels among TMDs. We included 134 TMDs (22 - 59 years old) who had no prior diagnosis of CVD or T2D, and not taking medications affecting iron and potassium homeostasis. Conventional cardiovascular risk factors were used to calculate the 10-year CVD risk, which was categorized as low (20%). FRS > 2%, which corresponded to the 75th percentile of FRS distribution in our study population, was used as a cut-off value to classify participants into two groups. Plasma iron and potassium levels were segregated into tertiles and their associations with 10-year CVD risk were quantified by multivariate-adjusted logistic regression to calculate the odd ratios (ORs) to being above the 75th percentile of 10-year CVD risk with the corresponding 95% confidence intervals (CIs). We found that 62.0% of participants had at least one of cardiovascular risk factors. Approximately 97.8% of TMDs had 10-year CVD risk 4.8 mmol/L led to an 83% risk reduction of having 10-year CVD risk > 2% (OR = 0.17, 95% CI: 0.04 - 0.82, P = 0.027). In conclusion, our findings showed that high plasma potassium levels associate with reduced 10-year CVD risk among TMDs. Interventions focused on monitoring of plasma potassium, particularly in those with existing cardiovascular risk factors, may help prevent CVD.

关键词： Cardiovascular Diseases 10-Year CVD Risk Cotonou Framingham Risk Score Plasma Potassium Taxi-Motorbike Drivers