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Journal of Magnesium and Alloys 2024年第3期12卷 954-965页

作者： Yimeng Chen Manuel Legrée jean-louis Bobet Alexander Kvit CAMECA Instruments Inc MadisonWI 53711USA ICMCB Universitéde BordeauxPessacCEDEX 33608France nIAC&Materials Science Department University of WisconsinMadisonWI 53706USA

The long-period-stacking-ordered(LpSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg *** current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STEM)and atom probe tomography(ApT)to investigate the structural and local chemical information of LpSO phases formed in Mg-ni-Y/Sm ternary alloys after extended isothermal *** on the alloying elements and their concentrations,Mg-ni-Y/Sm develops a two-phase LpSO+α-Mg structure in which the LpSO phase contains defects,hybrid LpSO structure,and Mg ***-STEM and ApT indicate non-stoichiometric LpSO with incomplete ni_(6)(Y/Sm)_(8) *** addition,the ApT quantitatively determines the local composition of LpSO and confirms the presence of ni within the Mg bonding *** results provide insight into a better understanding of the structure and hydrolysis properties of LpSO-Mg alloys.

关键词： Magnesium alloys Long-range ordering Atom probe tomography(ApT) STEM HAADF Hydrolysis properties.

Joint Management of Shared Resources, Issues and Conflicts of the nso and Oku Tribes in the ngongbaa Montane Forest Area, nWR of Cameroon

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natural Resources 2024年第6期15卷 149-172页

作者： jean-louis Tatah Elvis Kah Department of Geography Faculty of Arts Letters and Social Sciences University of Yaounde I Yaounde Cameroon School of Geology and Mining Engineering University of Ngaoundere Ngaoundere Cameroon

Wherever people live together in or near homelands that harbour joint natural resources such as forest, water, minerals, oil etc., they must collaborate, co-exist and share these resources irrespective of their genetic, social, cultural, and political peculiarities. This is not always the case when self-interest, ethnic divisions, elitist politics, economic interest and power tussle set in. The nso and Oku people who reside in the ngongbaa Forest area constitute an example of joint management of resources where at one period, their relationship over the management of the Oku Mountain Forest was cordial and at another, the relationship became conflictive. This study was designed to study the influence of the KIFp forest management policies on the nso indigenous forest Management system in ngongbaa Forest, and its implications. The data collected for the study was secured through the administration of a questionnaire to residents of 10 villages adjacent to the ngongbaa Forest, and forest users who carried out livelihood activities there between 1963 and 2015. These forest user groups include beekeepers, rat trappers, grazers, mushroom gatherers, ground honey/tree honey harvesters, carvers, etc. The investigation also extended to the traditional leaders of nso and Oku who are in charge of the land tenure systems. The findings show that the Oku Mountain Forest is jointly owned by the nso and Oku people. The nso own the eastern half of the forest known as ngongbaa Forest while the Oku own the western half, known as the Kilum Forest. The cordial relationship that existed between these people ensured the conservation of the forest. But the conflicts that later set in, especially due to the creation of the Kilum Mountain Forest project in 1987 later changed to the Kilum Ijim Forest project (KIFp) in 1992 sidelined the local communities which was contrary to the dispositions of the new Cameroon forest law enacted in 1994. Thus, the indigenous conservation practices became ig

关键词： Conflict Joint Management Shared Resources ngongbaa Kilum Conservation

Statistical Study of the Geoeffectivity of Halo Coronal Mass Ejections Associated with X-Class Flares during Solar Cycles 23 and 24

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Open Journal of Applied Sciences 2024年第4期14卷 950-960页

作者： Younoussa Diakite Christian Zoundi M’Bi Kabore jean louis Zerbo Laboratoire de Chimie Analytique de Physique Spatiale et Energ&#233tique (L@CAPSE) Physics Department Universit&#233 Norbert Zongo Koudougou Burkina Faso Laboratoire de Maté riaux d&#8217H&#233liophysique et Environnement (LAMHE) Physics Department Universit&#233 Nazi Boni Bobo-Dioulasso Burkina Faso

By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ejections associated with X-class flares appear to be among the most energetic events in solar activity given the size of the flares, the speed of the CMEs and the intense geomagnetic storms they produce. Out of eighty-six (86) X-class halo CMEs, thirty-seven (37) or 43% are highly geoeffective;twenty-four (24) or approximately 28% are moderately geoeffective and twenty-five (25) or 29% are not geoeffective. Over the two solar cycles (1996 to 2019), 71% of storms were geoeffective and 29% were not. For solar cycle 23, about 78% of storms were geoeffective, while for solar cycle 24, about 56% were geoeffective. For the statistical study based on speed, 85 halo CMEs associated with X-class flares were selected because the CME of 6 December 2006 has no recorded speed value. For both solar cycles, 75.29% of the halo CMEs associated with X-class flares have a speed greater than 1000 km/s. The study showed that 42.18% of halo (X) CMEs with speeds above 1000 km/s could cause intense geomagnetic disturbances. These results show the contribution (in terms of speed) of each class of halo (X) CMEs to the perturbation of the Earth’s magnetic field. Coronal mass ejections then become one of the key indicators of solar activity, especially as they affect the Earth.

关键词： CME Halo (X) Geoeffectivity Geomagnetic Storm Solar Flare Solar Cycle

Origin and diversification of maize: Two teosintes but different contributions

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Molecular plant 2024年第2期17卷 233-235页

作者： Jonathan Acosta-Bayona Gloria Leon-Martinez jean-philippe Vielle-Calzada Grupo de Desarrollo Reproductivo y Apomixis UGA Laboratorio Nacional de Genomica para la BiodiversidadCinvestav IrapuatoIrapuato Gto CP36825Mexico

The unique topographic,climatic,and latitudinal heterogeneity of Mesoamerica is crucial to understanding the evolutionary emergence of one of the richest cultural and biological regions in the planet and its impact on food *** divided between two regions of large biodiversity-lowland tropical or coastal zones and temperate or subtropical highlands sculpted by parallel sierras and their central plateau-the Mexican territory harbors more than 2000 endemic monocotyledonous species,including several hundred grasses(poaceae),particularly those belonging to the genus Zea,composed of maize(Zea mays ***)and its wild relatives,collectively referred as teosintes.

关键词： collective planet harbor

Improving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates

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Digital Communications and networks 2024年第2期10卷 369-379页

作者： Héber H.Arcolezi jean-François Couchot Bechara Al Bouna Xiaokui Xiao Inria andÉcole polytechnique(Ipp) PalaiseauFrance Femto-ST Institute Univ.Bourg.Franche-ComtéUBFCCNRSBelfortFrance TICKET Lab. Antonine University Hadat-BaabdaBaabdaLebanon School of Computing National University of SingaporeSingaporeSingapore

This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential privacy(LDp)*** to frequency estimation of a single attribute,the multidimensional aspect demands particular attention to the privacy ***,when collecting user statistics longitudinally,privacy progressively ***,the“multiple”settings in combination(i.e.,many attributes and several collections throughout time)impose several challenges,for which this paper proposes the first solution for frequency estimates under *** tackle these issues,we extend the analysis of three state-of-the-art LDp protocols(Generalized Randomized Response–GRR,Optimized Unary Encoding–OUE,and Symmetric Unary Encoding–SUE)for both longitudinal and multidimensional data *** the known literature uses OUE and SUE for two rounds of sanitization(***),i.e.,L-OUE and L-SUE,respectively,we analytically and experimentally show that starting with OUE and then with SUE provides higher data utility(i.e.,L-OSUE).Also,for attributes with small domain sizes,we propose Longitudinal GRR(L-GRR),which provides higher utility than the other protocols based on unary ***,we also propose a new solution named Adaptive LDp for LOngitudinal and Multidimensional FREquency Estimates(ALLOMFREE),which randomly samples a single attribute to be sent with the whole privacy budget and adaptively selects the optimal protocol,i.e.,either L-GRR or *** shown in the results,ALLOMFREE consistently and considerably outperforms the state-of-the-art L-SUE and L-OUE protocols in the quality of the frequency estimates.

关键词： Local differential privacy Discrete distribution estimation Frequency estimation Multidimensional data Longitudinal studies

Detection of Burned Areas through Spectral Indices Analysis of Sentinel-2A Satellite Images in the Abokouamékro Wildlife Reserve (Central, Côte D’Ivoire)

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Open Journal of Applied Sciences 2024年第1期14卷 205-222页

作者： Bob Kouakou Kouadio Sié Ouattara Alain Clément jean-Marc Gala Bi Zaouri jean-Luc Kouadio Kouassi jean-Luc Edouard Kouakou n’guessan Laboratoire des Sciences et Technologies de la Communication et de l’Information (LSTCI) Institut National Polytechnique Houphou&#235t Boigny (INP-HB) Yamoussoukro C&#244te d’Ivoire Laboratoire des Sciences Agronomiques et Génie Rural Institut National Polytechnique Houphou&#235t Boigny (INPHB) Yamoussoukro C&#244te d’Ivoire Ecole de Géomatique et du Territoire (EGT) Abidjan C&#244te d’Ivoire LARIS SFR MATHSTIC Université d’Angers Angers France Centre Universitaire de Recherche et d’application en Télédétection (CURAT) UFR des Sciences de la Terre et des Ressources Minières Abidjan C&#244te d’Ivoire Laboratoire de Botanique UFR Biosciences Université Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoire

In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of the dynamics of burnt areas within the Abokouamékro Wildlife Reserve (AWR) by employing the analysis of spectral indices derived from satellite imagery. The research methodology began with the calculation of mean indices and their corresponding spectral sub-indices, including nDVI, SAVI, nDWI, nDMI, BAI, nBR, TCW, TCG, and TCB, utilizing data from the Sentinel-2A satellite image dated January 17, 2022. Subsequently, a fuzzy classification model was applied to these various indices and sub-indices, guided by the degree of membership α, with the goal of effectively distinguishing between burned and unburned areas. Following the classification, the accuracies of the classified indices and sub-indices were validated using the coordinates of 100 data points collected within the AWR through GpS technology. The results revealed that the overall accuracy of all indices and sub-indices declines as the degree of membership α decreases from 1 to 0. Among the mean spectral indices, nDVI-mean, SAVI-mean, nDMI-mean exhibited the highest overall accuracies, achieving 97%, 95%, and 90%, respectively. These results closely mirrored those obtained by sub-indices using band 8 (nDVI-B8, SAVI-B8, and nDMI-B8), which yield respective overall accuracies of 93%, 92%, and 89%. At a degree of membership α = 1, the estimated burned areas for the most effective indices encompassed 2144.38 hectares for nDVI-mean, 1932.14 hectares for mean SAVI-mean, and 4947.13 hectares for mean nDMI-mean. A prospective approach involving the amalgamation of these three indices could have the potential to yield improved outcomes. This study could be a substantial contribution to the discrimination of bushfires in Côte d’Ivoire.

关键词： Spectral Indices Wildfire Burned Areas Abokouamékro Wildlife Reserve Côte D’Ivoire

Lateral ring compression test applied to a small caliber steel jacket:Identification of a constitutive model

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Defence Technology（防务技术） 2024年第6期36卷 133-148页

作者： Yann Coget Yael Demarty Christophe Czarnota Anthony Bracq jean-Sebastien Brest Alexis Rusinek French-German Research Institute of Saint-louis 5 Rue Du General Cassagnou68300 Saint-LouisFrance Laboratoire d'Etude des Microstructures et de Mecanique des Materiaux(LEM3) CNRSUniversite de LorraineArts&Metiers ParisTechF-57000 MetzFrance

The evolution of threats and scenarios requires continuous performance improvements of ballistic protections for armed *** a modeling point of view,it is necessary to use sufficiently precise material behavior models to accurately describe the phenomena observed during the impact of a projectile on a protective *** this context,the goal of this paper is to characterize the behavior of a small caliber steel jacket by combining experimental and numerical *** experimental method is based on the lateral compression of ring specimens directly machined from the thin and small *** speeds and temperatures are considered in a quasi-static regime in order to reveal the strain rate and temperature dependencies of the tested *** Finite Element Updating Method(FEMU)is *** results are coupled with an inverse optimization method and a finite element numerical model in order to determine the parameters of a constitutive model representative of the jacket *** of the present model are verified against experimental results and a parametric study as well as a discussion on the identified material parameters are *** results indicate that the strain hardening parameter can be neglected and the behavior of the thin steel jacket can be described by a modeling without strain hardening sensitivity.

关键词： Full metal jacket ammunition Lateral ring compression Inverse identification numerical simulation

Deep eutectic solvent-driven self-assembly of metal mercaptide complexes with enzyme-mimicking activities for detection of uric acid through one-step cascade catalytic reaction

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Green Chemical Engineering 2024年第1期5卷 75-84页

作者： jean Claude Munyemana Jia Chen Xin Li Yangxia Han Hao Tang Hongdeng Qiu CAS Key Laboratory of Chemistry of northwestern plant Resources and Key Laboratory for natural Medicine of Gansu province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100039China Department of pharmacy Gansu Provincial HospitalLanzhou730000China

This work presents a generic strategy to create a series of metal mercaptides complexes via coordination selfassembly between transition metals(Mn,Cu,Co,Fe,and ni)and cysteine(Cys)by forming the sulfur-metal *** strategy involves dissolving metal chlorides and Cys into deep eutectic solvents(DES),followed by the precipitation of metal mercaptides complexes(such as Cys-Mn)by adding water as an antisolvent,where DES serves as the solvent,shape directing,and capping agent,thereby preventing the formation of other metal ***,the prepared complexes possess both laccase and peroxidase-like properties,allowing the design of a technique for the detection of L-3,4-dihydroxyphenylalanine(L-DOpA)and uric acid,*** prepared Cys-Mn can linearly oxidize L-DOpA with its concentrations from 0.1 to 130μM and the detection limit was calculated to be 75.5 n ***,the Cys-Mn can mimic the activity of peroxidase towards oxidization of o-phenylenediamine at neutral p H,allowing single-step and one-pot cascade reactions for visual and fluorometric measurements of uric acid(UA)that could work in the range of 0.2-500μM UA with a detection limit of 0.06μM and 0.054μМ,*** assay was successful in detecting UA in serum and urine samples with relative standard deviation(RSD)ranging from 7.3%to 10.2%and 3.0%-8.5%respectively,suggesting that it may prove useful in medical diagnostic testing.

关键词： Metal-mercaptides Deep eutectic solvents Self-assembly peroxidase-mimic catalyst Uric acid detection

Optimisation of Thermal Comfort of Building in a Hot and Dry Tropical Climate: A Comparative Approach between Compressed Earth/Concrete Block Envelopes

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Journal of Minerals and Materials Characterization and Engineering 2024年第1期12卷 1-16页

作者： Arnaud louis Sountong-noma Ouedraogo Césaire Hema Sjoerd Moustapha n’guiro philbert nshimiyimana Adamah Messan Laboratoire Eco-Matériaux et Habitat Durable (LEMHaD) Institut International de l’Ingénierie de l’eau et de l’environnement (Institut 2iE) Rue de la science 01 BP 594 Ouagadougou Burkina Faso

Compressed earth blocks (CEB) are an alternative to cement blocks in the construction of wall masonry. However, the optimal architectural construction methods for adequate thermal comfort for occupants in hot and arid environments are not mastered. This article evaluates the influence of architectural and constructive modes of buildings made of CEB walls and concrete block walls, to optimize and compare their thermal comfort in the hot and dry tropical climate of Ouagadougou, Burkina Faso. Two identical pilot buildings whose envelopes are made of CEB and concrete blocks were monitored for this study. The thermal models of the pilot buildings were implemented in the SketchUp software using an extension of Energyplus. The models were empirically validated after calibration against measured thermal data from the buildings. The models were used to do a parametric analysis for optimization of the thermal performances by simulating plaster coatings on the exterior of walls, airtight openings and natural ventilation depending on external weather conditions. The results show that the CEB building displays 7016 hours of discomfort, equivalent to 80.1% of the time, and the concrete building displays 6948 hours of discomfort, equivalent to 79.3% of the time. The optimization by modifications reduced the discomfort to 2918 and 3125 hours respectively;i.e. equivalent to only 33.3% for the CEB building and 35.7% for the concrete building. More study should evaluate thermal optimizations in buildings in real time of usage such as residential buildings commonly used by the local middle class. The use of CEB as a construction material and passive means of improving thermal comfort is a suitable ecological and economical option to replace cementitious material.

关键词： Compressed Earth Blocks Hot and Dry Climate Thermal Comfort Architectural Optimization of Thermal Models Cement Blocks Empirical Validation

Molecular Characterization of Gastrointestinal Stromal Tumors (Gist) and Contribution of Immunohistochemistry in Congolese from Kinshasa

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Open Journal of Gastroenterology 2024年第4期14卷 109-116页

作者： Rive Lukuaku Jérémie Okumadi Fabrice Bokambandja Andy Mbangama Vincent Mbatu Georges Mvumbi jean-louis Mumbere David Azako Serge pezo Dieudonné Mvumbi Faculty of Medicine Bel Campus Technological University Kinshasa DR Congo Department of Anatomy and pathological Cytology University Clinics of Kinshasa Kinshasa DR Congo Department of Gyneco-Obstetrics University Clinics of Kinshasa Kinshasa DR Congo Molecular Biology Department Faculty of Medicine University of Kinshasa Kinshasa DR Congo Institute of Medical Immunology Free University of Brussels Ixelles Belgium

Introduction: The differentiation of digestive tumors very often requires the use of techniques currently not widely in use in the Democratic Republic of Congo (DRC), such as immunohistochemistry. This is perfectly verified for GISTs whose precise, or at least highly certain, diagnosis can only be made using immunohistochemical markers. This underuse of these techniques due to lack of equipment and human skills explains the limited epidemiological data available to date, thus leading to untargeted and too often late treatment of patients. Research question: What contribution can immunohistochemical markers make to the diagnosis of digestive tract tumours? Objective: Discuss the contribution of immunohistochemical markers in the diagnosis of GIST and provide basic data on the epidemiology of these nosological entities in Kinshasa. Methodology: This was a retrospective study carried out at the LEBOMA private anatomy and pathological cytology centre. The main inclusion criterion was any digestive tract block or slide whose diagnosis of GIST had been requalified after review by at least 2 pathologists. An immuhistochemical study was performed using an automated technique (with a Ventana XT machine) using a panel of antibodies: CD-117 and DOG-1 which are listed in the literature as strongly correlated with the occurrence of GIST, all slides were made at Hj Hospital using an OLYMpUS BX41 co-observation microscope. Results: Of 601 cases of digestive tumors recorded during the concerned period, 32 (5.32%) concerned GIST. This prevalence was confirmed by our immunohistochemical results where the expression of CD117 and that of DOG-1 were positive in 90.6% and 100% of cases which prevalence is high compared with the worldwide prevalence according to the literature, respectively. The distribution of the patients concerned was made with a sex ratio of 1.6 women/men with a median age of 53 years. Most cases (81%) had a gastric location and were fusiform GISTs. Conclusion: Gastro

关键词： Digestive Tumors GIST Immunohistochemistry CD117 DOG-1