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Journal of Power and Energy Engineering 2021年第5期9卷 76-92页

作者： Abraham Dandoussou pierre kenfack Stève Ngoffe Perabi Martin Kamta University of Buea Department of Electrical and Power Engineering Higher Technical Teachers’ Training College (HTTTC) Kumba Cameroon University of Douala Department of Electrical Engineering and Industrial Computing Institut Universitaire de Technologie Douala Cameroon University of Ngaoundere Department of Electrical Engineering Energetic and Automation National School of Agro-Industrial Sci-ences Ngaoundere Cameroon

Maximum Power Point Tracking (MPPT) algorithms are now widely used in PV systems independently of the weather conditions. In function of the application, a DC-DC converter topology is chosen without any previous performance test under normal weather conditions. This paper proposes an experimental evaluation of MPPT algorithms according to DC-DC converters topologies, under normal operation conditions. Four widely used MPPT algorithms i.e. Perturb and Observe (P & O), Hill Climbing (HC), Fixed step Increment of Conductance (INCF) and Variable step Increment of Conductance (INCV) are implemented using two topologies of DC-DC converters i.e. buck and boost converters. As input variables to the PV systems, recorded irradiance and temperature, and extracted photovoltaic parameters (ideality factor, series resistance and reverse saturation current) were used. The obtained results show that buck converter has a lot of power losses when controlled by each of the four MPPT algorithms. Meanwhile, boost converter presents a stable output power during the whole day. Once more, the results show that INCV algorithm has the best performance.

关键词： MPPT Algorithms DC-DC Converters Photovoltaic Parameters Normal Operating Conditions

Pregnancy and Obstetrical Outcomes Following Treatment for Cervical Intra-Epithelial Neoplasia (CIN) in Two Hospitals of a Low-Resource Country

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Advances in Reproductive Sciences 2024年第1期12卷 51-59页

作者： Bruno kenfack Clovis-Achille Tanekeu Atem Bethel Ajong Zabdielle Blonde Goufack kenfack Patrick Petignat pierre Marie Tebeu Department of Gynecology and Obstetrics Faculty of Medicine and Pharmaceutical Science University of Dschang Dschang Camer-on Institur Supérieur des Sciences de la Santé Université des Montagnes Bangangté Cameroon Kekem MD District Hospital West Region Cameroon Department of Epidemiology and Public Health Faculty of Medicine and Pharmaceutical Science University of Dschang Dschang Cameron Geneva University Hospitals Genevas Switzerland Faculty of Medicine and Biomedical Science University of Yaounde I Yaounde Cameroon

Objective: In Cameroon, more than 80% of women suffering from cervical intraepithelial neoplasia (CIN) are within the reproductive age. This study intended to analyze the pregnancy outcomes following cervical treatment in Cameroon. Methods: This was a cohort study with two years retrospective data collection involving 82 women who underwent cervical treatment for CIN in two Cameroonian hospitals from January 2015 to December 2017. Data were collected from CIN treatment to end of pregnancy where applicable. Data analysis was done using Epi Info software version 3.5.4. Results: We collected data from 82 patients aged 27 to 48 years, with a mean age of 36.5 (SD: 5.3) years. During the study period, 33 out of 82 participants became pregnant 40.2 [29.56 - 51.66]%. The factor associated with pregnancy occurrence after treatment was age less than 35 years (Odds ratio = 4.37 [1.7 - 11.2]. From the 33 pregnancies recorded, 17 (51.5%) ended in a delivery, amongst which 15 (88.2%) were vaginal. Conclusion: Pregnancy frequency over two years following cervical treatment for CIN was relatively good, and younger women (age 35 years) were significantly more like to have conceived compared to their older counterparts. Post-treatment delivery outcomes seem to be similar to those in the general population.

关键词： Cervical Intraepithelial Neoplasia Cervical Treatment Pregnancy Outcome

Cavity optomechanics with directionally squeezed light

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 181-182页

作者： pierre Meystre Department of Physics and College of Optical Sciences University of ArizonaTucson 85721USA

It is well understood that the Heisenberg uncertainty principle imposes a fundamental limit on the precision of quantum *** way to get around this difficulty is to exploit quantum states that minimize the uncertainty on the observable of interest,increasing in the process the uncertainty on the conjugate *** states of the electromagnetic field.

关键词： field observable quantum

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Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

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Re-evaluation of recent research on metabolic utilization of energy in poultry: Recommendations for a net energy system for broilers

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Animal Nutrition 2024年第1期16卷 62-72页

作者： Jean Noblet Aye-Cho Tay-Zar Shu-Biao Wu Pairat Srichana pierre Cozannet pierre-Andre Geraert Mingan Choct INRAE Charoen Pokphand Foods Public Company Limited (CPF) School of Environmental and Rural Science University of New England Adisseo France S.A.S.

Different energy systems have been proposed for energy evaluation of feeds for domestic animals. The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy(DE), and fecal, urinary and fermentation gases energy losses to calculate metabolizable energy(ME). In the case of ruminants and pigs, the net energy(NE) system, which takes into account the heat increment associated with the metabolic utilization of ME, has progressively replaced the DE and ME systems over the last 50 years. For poultry, apparent ME(AME) is used exclusively and NE is not yet used widely. The present paper considers some important methodological points for measuring NE in poultry feeds and summarizes the available knowledge on NE systems for poultry. NE prediction equations based on a common analysis of three recent studies representing a total of 50 complete and balanced diets fed to broilers are proposed; these equations including the AME content and easily available chemical indicators have been validated on another set of 30 diets. The equations are applicable to both ingredients and complete diets. They rely primarily on an accurate and reliable AME value which then represents the first limiting predictor of NE value. Our analysis indicates that NE would be a better predictor of broiler performance than AME and that the hierarchy between feeds is dependent on the energy system with a higher energy value for fat and a lower energy value for protein in an NE system. Practical considerations for implementing such an NE system from the commonly used AME or AMEn(AME adjusted for zero nitrogen balance) systems are presented. In conclusion, there is sufficient information to allow the implementation of the NE concept in order to improve the accuracy of feed formulation in poultry.

关键词： Poultry Feed evaluation Net energy Energy system

The importance of increasing primary vaccinations against COVID-19 in Europe

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Infectious Disease Modelling 2024年第1期9卷 1-9页

作者： pierre-Yves Boelle Eugenio Valdano Sorbonne Universite INSERMInstitut Pierre Louis d’Epidemiologie et de Sante PubliqueF75012ParisFrance

In the European Union,mass vaccination against COVID-19 staved off the strict restrictions that had characterized early epidemic ***,vaccination campaigns are focusing on booster doses,and primary vaccinations have all but ***,52 million European adults are *** investigated if reaching the still unvaccinated population in future vaccination campaigns would substantially decrease the current burden of COVID-19,which is *** focused on vaccination homophily,whereby those who are unvaccinated are mostly in contact with other unvaccinated,making COVID-19 circulation *** quantified vaccination homophily and estimated its impact on COVID-19 *** used an online survey of 1,055,286 people from 22 European countries during early *** computed vaccination homophily as the association between reported vaccination status and perceived vaccination uptake among one's own social contacts,using a case-referent design and a hierarchical logistic *** used this information in an analysis of the COVID-19 reproduction ratio to determine the impact of vaccine homophily in *** homophily was present and strong everywhere:the average odds ratio of being vaccinated for a 10-percentage-point increase in coverage among contacts was 1.66(95%CI=(1.60,1.72)).Homophily was positively associated with the strictness of COVID-19-related restrictions in 2020(Pearson=0.49,P=.03).In the countries studied,12%-to-18%of the reproduction ratio would be attributable to vaccine *** vaccination homophily may curb the reproduction ratio substantially even to the point of preventing recurrent epidemic *** addition to boosting those already vaccinated,increasing primary vaccination should remain a high priority in future vaccination campaigns,to reduce vaccination homophily:this combined strategy may decrease COVID-19 burden.

关键词： COVID-19 Vaccination campaign Reproduction ratio Vaccination homophily Survey Europe

A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins

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Journal of Renewable Materials 2024年第3期12卷 397-425页

作者： Antonio Pizzi Marie-pierre Laborie Zeki Candan LERMAB University of LorraineFaculty of SciencesBlvd des AiguillettesNancy54000France Chair of Forest Biomaterials Institute of Earth and Environmental SciencesUniversity of FreiburgFreiburgGermany Freiburg Materials Research Center Alberst Ludwig University of FreiburgFreiburg79104Germany Department of Forest Products Engineering Faculty of ForestryIstanbul UniversitySariyerIstanbul34473Turkey

Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based *** are a definite class of sustainable materials of the forestry *** have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several *** review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and *** constitutes a basic but essential summary of what is necessary to know of these sustainable *** doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.

关键词： Tannins flavonoids sources extraction methods analysis methods

Immunobiodiversity:Conserved and specific immunity across land plants and beyond

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Molecular Plant 2024年第1期17卷 92-111页

作者： Baptiste Castel Karima El Mahboubi Christophe Jacquet pierre-Marc Delaux Laboratoire de Recherche en Sciences Végétales(LRSV) Universitéde ToulouseCNRSUPSToulouse INPCastanet-TolosanFrance

Angiosperms represent most plants that humans cultivate,grow,and ***,angiosperms are only one of five major land plant *** a whole lineage,plants also include algal *** these clades represent a tremendous genetic diversity that can be investigated to reveal the evolutionary history of any given *** this review,we describe the current model of the plant immune system,discuss its evolution based on the recent literature,and propose future directions for the *** angiosperms,plant–microbe interactions have been intensively studied,revealing essential cell surface and intracellular immune receptors,as well as metabolic and hormonal defense *** diversity at the genomic and functional levels demonstrates the conservation of these pathways across land plants,some of which are beyond *** basis of the conserved mechanisms,lineage-specific variations have occurred,leading to diversified reservoirs of immune *** rare cases,this diversity has been harnessed and successfully transferred to other species by integration of wild immune receptors or engineering of novel forms of receptors for improved resistance to *** propose that exploring further the diversity of immune mechanisms in the whole plant lineage will reveal completely novel sources of resistance to be deployed in crops.

关键词： evolution MPMI immunity plant evoMPMI symbiosis

Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia

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Geodesy and Geodynamics 2024年第1期15卷 13-26页

作者： Xianjie Li Jean-pierre Barriot Bernard Ducarme Marania Hopuare Yidong Lou Geodesy Observatory of Tahiti University of French PolynesiaFaa'a 98702French Polynesia Catholic University of Louvain Georges Lemaître Centre for Earth and Climate Research(ELI)1348 Louvain-la-NeuveBelgium GNSS Research Center Wuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same *** verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good *** obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/*** absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/*** discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.

关键词： GPS Tide gauges Sea level changes Vertical land motion

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Incorporating mitigation strategies in machine learning for landslide susceptibility prediction

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Geoscience Frontiers 2024年第5期15卷 399-414页

作者： Hai-Min Lyu Zhen-Yu Yin pierre-Yves Hicher Farid Laouafa Key Laboratory for Resilient Infrastructures of Coastal Cities(MOE) College of Civil and Transportation EngineeringShenzhen UniversityShenzhenChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Research Institute of Civil Engineering and Mechanics(GeM) UMR CNRS 6183Ecole Centrale de NantesFrance National Institute for Industrial Environment and Risks(INERIS) Verneuil-en-HalatteFrance

This study proposes an approach that considers mitigation strategies in predicting landslide susceptibility through machine learning(ML)and geographic information system(GIS)*** models,such as random forest(RF),logistic regression(LR),and support vector classification(SVC)are incorporated into GIS to predict landslide susceptibilities in Hong *** consider the effect of mitigation strategies on landslide susceptibility,non-landslide samples were produced in the upgraded area and added to randomly created samples to serve as ML models in training *** scenarios were created to compare and demonstrate the efficiency of the proposed approach;Scenario I does not considering landslide control while Scenario II considers mitigation strategies for landslide *** largest landslide susceptibilities are 0.967(from RF),followed by 0.936(from LR)and 0.902(from SVC)in Scenario II;in Scenario I,they are 0.986(from RF),0.955(from LR)and 0.947(from SVC).This proves that the ML models considering mitigation strategies can decrease the current landslide *** comparison between the different ML models shows that RF performed better than LR and SVC,and provides the best prediction of the spatial distribution of landslide susceptibilities.

关键词： Machine learning Landslide susceptibility Spatial prediction Mitigation strategies