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Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the Detection of SARS-CoV-2 in Gabon

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Advances in Infectious Diseases 2024年第2期14卷 469-477页

作者： Samira Zoa Assoumou Ulrich Leger Davy Mouangala Ludovic Mewono Davy-Christ Angoune Ndong Guy Paterne Malonga Mbembo Nely Meungang Alain Moutsinga Elvyre Anita Mbongo Kama Rodrigue Mintsa Nguema Dpartement de Bactriologie-Virologie Universit des Sciences de la Sant Libreville Gabon laboratoire Professeur Daniel Gahouma Libreville Gabon departement des Sciences de la vie et de la Terre Ecole Normale Suprieure Libreville Gabon Centre de sant de Glass Libreville Gabon laboratoire National de Sant Publique Libreville Gabon Dpartement de Biologie et Ecologie Animale Centre National de la Recherche Scientifique et Technologique Libreville Gabon laboratoire decologie des Maladies Transmissibles (LEMAT) Universit Libreville Nord (ULN) Libreville Gabon

1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to december 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission.

关键词： SARS-CoV-2 Rapid Diagnostic Test Evaluation COVID-19 Antigen Performance

Electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds by first-principles method

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Journal of Rare Earths 2024年第1期42卷 147-154,I0006页

作者： Sajid Khan Dil Faraz Khan R.Neffati Tariq Usman Muhammad Waqar Ahsraf Shamim Khan Saeed Ullah Jan G.Murtaza department of Physics University of Science&Technology BannuBannu28100Pakistan department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia laboratoire de Physique de la Matiere Condensee Departement de PhysiqueFaculte des Sciences de TunisUniversite Tunis El ManarCampus Universitaire1060TunisTunisia department of Physics Shaoxing UniversityShaoxing312000China department of Mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityAlkhobar31952Saudi Arabia Materials Modeling lab Department of PhysicsIslamia College Peshawar25120KhyberPakhtunkhwaPakistan

In this work the structural,electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds were investigated comprehensively using first principles *** electronic properties were studied using PBE GGA,TB-mBJ and hybrid(YS-PBE0)*** the structural parameters of optimized structures are in harmonious agreement to the available *** band structure study illustrates that the titled materials manifest metallic and semi metallic nature using PBE and TB-mBJ potentials while they show wide band gap semiconducting behavior by following hybrid(YS-PBE0)*** density of states(TDOS)and partial density of states(PDOS)were also calculated to glimpse the contribution of orbitals of atoms in the formation of *** properties were studied by using BoltzTraP2 code employed to *** get enormous values of Seebeck coefficient(S),power factor(PF)and thermoelectric figure of merit(ZT)for all the samples YbMg_(2)X_(2)(X=P,As,Sb,Bi),Moreover,the overwhelming transport properties for the titled compounds indicate the optimum level of carriers’concentration which pinpoints these materials to be better thermoelectrics in the 1-2-2 zintl family.

关键词： Zintl compounds Hybrid functional Band structure Thermoelectrics Rare earths

How can the forest sector mitigate climate change in a changing climate? Case studies of boreal and northern temperate forests in eastern Canada

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Forest Ecosystems 2022年第2期9卷 267-287页

作者： Lucas Moreau Evelyne Thiffault Dominic Cyr Yan Boulanger Robert Beauregard departement des sciences du bois et de la foret Universite LavalQuebecCanada Science and Technology Branch Environment and Climate Change CanadaGatineauCanada laurentian Forestry Centre Natural Resources CanadaQuebecCanada

Background:Forest based climate mitigation emerged as a key component of the Paris Agreement,and thus re-quires robust science to reduce uncertainties related to such *** aim of this study was to assess and compare the cumulative effects on carbon dynamics of forest management and climate change on boreal and northern temperate forest sector in eastern Canada for the 2020–2100 ***:We used the spatially explicit forest landscape model laNDIS-II and its extension Forest Carbon Suc-cession,in conjunction with the Carbon Budget Model for Harvested Wood Products *** simulated the dynamics of forest composition and carbon flows from forest ecosystems to wood products and their substitution effect on markets under increasing climate forcing,according to a tonne-year *** were con-ducted for a series of forest management scenarios based on realistic practices principally by clearcut in the boreal territory and continuous-cover forestry in the northern temperate *** scenarios included:i)a business-as-usual scenario(BaU),representing the current management strategy,ii)increased harvesting by 6.3%to 13.9%,iii)increased conservation(*** harvesting by 11.1%to 49.8%),iiii)and a scenario representing the natural evolution of the forest landscape(*** any management activity).Results:Our study revealed that increasing harvesting levels had contrasting effects on the mitigation potential in northern temperate(enhance net sequestration)and boreal forest sector(enhance net emissions)in comparison to the BaU from 2040 onwards,regardless of the future *** storage in wood products and the substi-tution effect were not sufficient to offset carbon emissions from ***,climate change had a strong impact on the capacity of both landscapes to act as carbon *** temperate landscapes became a net source of carbon over time due to their greater vulnerability to climate change than boreal landsc

关键词： Climate change Carbon Forest sector Forest management Boreal landscapes Northern temperate landscape Mitigation potential

Geochemistry of the volcanic rocks from Bioko Island(“Cameroon Hot Line”)： Evidence for plume-lithosphere interaction

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Geoscience Frontiers 2016年第5期7卷 743-757页

作者： Fadimatou Ngounouno Yamgouot Bernard Déruelle Isaac Bertrand Gbambié Mbowou Ismaila Ngounouno Daniel demaiffe departement des Sciences de la Terre Faculte des Sciences Universite de Ngaoundere B.P. 454 Ngaoundere Cameroon laboratoire de Magmatologie et Ceochimie lnorganique et Experimentale (MAGIE) Institut de Physique du Globe de Paris UMR 7154 Universite Pierre et Marie Curie 4 place Jussieu 75252 Paris cedex 05 France departement des mines et de la geologie Ecole de Geologie et d'Exploitation Miniere (EGEM) Universite de Ngaoundere B.R 115 Meiganga Cameroon laboratoire de Geochimie lsotopique et Geodynamique Chimique DSTE (CP 160/02) Universite Libre de Bruxelles 50 av. Roosevelt 1050 BruxellesBelgium

Bioko Island（3008 m a.s.l） is located in the presently more active volcanic zone of the Cameroon Line and composed essentially of alkaline basalts and hawaiites, and lesser mugearites. The rocks show microlitic porphyritic texture with phenocrysts of olivine（83% 〈 Fo 〈 87%） and clinopyroxene in a matrix of plagioclase, clinopyroxene and oxides. Hawaiites and mugearites also include phenocrysts of plagioclase（An62-67Ab35-32Or3-1）. Major element variation diagrams show an increase in Si O2, Al2O3, Na2 O and K2 O with increasing Mg O for the studied rock groups. The rocks are characterized by low（^86Sr/^87Sr）i ratios（0.70320e0.70406）, high 3Nd（t） values（2.56e4.33） and high（^206Pb/^204Pb）i ratios（20.032e20.035） *** are enriched in LILE and LREE, and have（Hf/Sm）N= 0.57e1.16. These geochemical signatures are similar to those of the Mount Cameroon rocks, and might be attributed to low degrees of partial melting from a garnet-amphibole-bearing mantle source. The trace elements and isotopic compositions suggest that the parental magma source might have involved HIMU- and EM1-components.

关键词： Geochemistry HIMU-EM1 Volcanic rocks Bioko Cameroon Hot Line

Geodesic equation in non-commutative gauge theory of gravity

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Chinese Physics C 2022年第10期46卷 193-206页

作者： Abdellah Touati Slimane Zaim laboratoire de Physique des Rayonnements et de leurs Interactions avec la Matiere departement de Physique Faculte des Sciences de la Matiere Universite de Batna-1Batna 05000Algeria departement de Physique Faculte des Sciences de la Matière Universitéde Batna-1Batna 05000Algeria

In this study,we construct a non-commtative gauge theory of the modified structure of the gravitational field using the Seiberg-Witten map and the general tetrad fields of Schwarzschild space-time to show that the noncommutative geometry removes the singularity at the origin of the black hole,thus obtaining a non-singular Schwarzschild black *** geodetic structure of this black hole presents new types of motion next to the event horizon within stable orbits that are not allowed by the ordinary Schwarzschild *** noncommutative periastron advance of the Mercury orbit is obtained,and with the available experimental data,we find a parameter of non-commutativity on the order of 10^(-25)s·kg^(-1).This result shows that the new fundamental length,√h■,is on the order of 10^(-31)m.

关键词： non-commutative geometry gauge gravity Schwarzschild space-time geodesic equation

Pure forsterite in Nyiragongo lavas: evidence for subsolidus oxidation of volcanic rocks

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Acta Geochimica 2022年第1期41卷 12-23页

作者： Innocent Badriyo Agama Gilles Chazot Pierre Kamgang departement des Sciences de la Terre Faculte Des SciencesUniversitede YaoundeIB.P.812YaoundeCameroon laboratoire Geosciences Ocean Institut Universitaire Europe´en de la MerUniversitede Brest(UBO)UMR 6538Place Copernic29280 PlouzaneFrance Observatoire Volcanologique de Goma B.P.484GomaNord-KivuDemocratic Republic of the Congo

Some volcanic rocks from Nyiragongo volcano in the democratic Republic of Congo contain highly oxidized olivine *** olivines crystals are made of two phases,dark olivine on backscattered electron images of pure forsterite composition and grey Mg-poor areas made of olivine and iron-rich *** of the initial composition confirms that they are primary olivine with late separation of two different olivine *** forsterite is enriched in SiO_(2) but contains lower amounts of CaO than Fe-rich areas,in agreement with expected partitioning of these elements related to the composition of the ***-rich oxides formed around or inside the olivine crystals during the separation process and confirm a highly oxidized environment during their *** propose that this separation occurred during subsolidus recrystallization under high fO_(2) conditions of the olivine crystals after cooling of the volcanic *** provides evidences for circulation of iron-rich fluids or gas inducing deuteritic processes occurring in the large volcanic cone of the Nyiragongo,in relation with the presence of a shallow magma chamber connected to a large and permanent lava lake.

关键词： Nyiragongo Olivine Forsterite Oxidation

Urban landscape structure anatomy:Structure patterns and typology identification in the space-time of Setif City,Algeria

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Frontiers of Architectural Research 2022年第3期11卷 421-439页

作者： Hodne Sami Belmahdi Abderezak Djemili laboratoire Architecture Urbanisme et Transport:HabitatPaysage et Mobilite Urbaine(LAUTr-HPM)Institut d'Architecture et d’UrbanismeUniversite Batna 1 HadJ LakhdarBatna 05000Algeria laboratoire Habitat et Environnement(LHE) Departement d’ArchitectureInstitut d’Architecture et des Sciences de la TerreUniversite Ferhat Abbas Setif 1Setif 19000Algeria

The definition of urban form and its elements raises a wide debate in urban *** study presents a proposal to understand the structuring of the urban landscape of Setif City over 170 years(1848-2018)by abstracting its main elements into permanent structure(PSUL).It corresponds to the street network,more static to the change of the town plan,and flexible structure(FSul),more resilient to change and explains the superimpositions of morphological components(plot,building,and land use).This work aims to identify typological patterns of structures suggested in space-time through the inspection of the growth of the street network and the filling of morphological layers framed by the concept of *** methodology is based on syntactic(diachronic)morphogenetic analysis,with statistical analyses as unsupervised *** indicate that PSUL presents an accumulation of microincrements produced with a similar degree of coherence in different urban fabrics,which explain the local patterns of street network *** typology of FSul patterns indicates an unbalanced growth by the arrangement between morphological elements,resulting in a variation in the degree of urbanity.

关键词： Urban landscape structure Permanent structure Flexible structure Patterns

Static and dynamic stability responses of multilayer functionally graded carbon nanotubes reinforced composite nanoplates via quasi 3D nonlocal strain gradient theory

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defence Technology（防务技术） 2022年第10期18卷 1778-1809页

作者： Ahmed Amine Daikh Mohamed Sid Ahmed Houari Mohamed Ouejdi Belarbi Salwa A.Mohamed Mohamed A.Eltaher laboratoire D'etude des Structures et de Mecanique des Materiaux Departement de Genie CivilFacultedes Sciences et de La TechnologieUniversite Mustapha Stambouli B.P.305R.P.29000MascaraAlgeria laboratoire de Genie Energetique et Materiaux LGEMUniversite de BiskraB.P.145R.P07000BiskraAlgeria department of Engineering Mathematics Zagazig UniversityP.O.Box 44519ZagazigEgypt Faculty of Engineering Mechanical Engineering DepartmentKing Abdulaziz UniversityP.O.Box 80204JeddahSaudi Arabia Faculty of Engineering Mechanical Design and Production DepartmentZagazig UniversityP.O.Box 44519ZagazigEgypt

This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)*** nanoscale and microstructure influences are considered through a modified nonlocal strain gradient continuum *** on power-law functions,four different patterns of CNTs distribution are considered in this analysis,a uniform distribution UD,FG-V CNTRC,FG-X CNTRC,and FG-O CNTRC.A 3D kinematic shear deformation theory is proposed to include the stretching influence,which is neglected in classical ***'s principle is applied to derive the governing equations of motion and associated boundary *** solutions are developed based on Galerkin method to solve the governing equilibrium equations based on the generalized higher-order shear deformation theory and the nonlocal strain gradient theory and get the static bending,buckling loads,and natural frequencies of *** with previous works is presented.A detailed parametric analysis is carried out to highlight the impact of thickness stretching,length scale parameter(nonlocal),material scale parameter(gradient),CNTs distribution pattern,geometry of the plate,various boundary conditions and the total number of layers on the stresses,deformation,critical buckling loads and vibration *** new results are also reported in the current study,which will serve as a benchmark for future research.

关键词： 3D shear deformation theory Free vibration Buckling Bending Galerkin method Functionally graded nanotube Nonlocal strain gradient theory

Pyrolysis of olive residue/low density polyethylene mixture：Part Ⅰ Thermogravimetric kinetics

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燃料化学学报 2008年第6期36卷 672-678页

作者： ABOULKAS A E1 HARFI K El BOUADILI A laboratoire de Recherche sur la Reactivites des Materiaux et l Optimisation des Procedes ＂REMATOP＂ Departement de chimie Faculte des Sciences Semlalia Universite Cadi Ayyad BP 2390 40001 Marrakech Maroc departement de chimie Faculte polydisciplinaire de Beni-Mellal Universite Sultan Moulay Slimane BP 592 23000 Beni-Mellal Maroc laboratoire de Chimie Organique et Analytique Departement de chimie Faculte des Sciences et Techniques de Beni-Mellal Universite Sultan Moulay Slimane BP 523 23000 Beni-Mellal Maroc

This paper demonstrates the thermal pyrolysis of olive residue,low density polyethylene(LDPE) and olive residue/LDPE mixture in an inert atmosphere of N2 using thermogravimetric analysis(TGA).Measurements were carried out in the temperature range 300K^973K at heating rates of 2K/min,10K/min,20K/min and 50K/*** on the results obtained,three temperature regimes were selected for studying the non-isothermal kinetics of olive residue/LDPE *** first two were dominated by the olive residue pyrolysis,while the third was linked to the LDPE pyrolysis,which occurred at much higher *** between the experimental and calculated TG/DTG profiles were considered as a measurement of the extent of interactions occurring on *** maximum degradation temperatures of each component in the mixture were higher than those the individual components;thus an increase in thermal stability was *** kinetic parameters associated with thermal degradation were determined using Friedman isoconversional method.

关键词：高温分解反应低密度聚乙烯动力学 LDPE