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Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International Journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki biswas Nicola J.Wagner Ofentse m.moroeng DSI-NRF CImERA/PPm Research Group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the madzaringwe Formation in makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous b-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+mn)and(Fe+mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： macerals Coal facies Geochemical-indices Hydrothermal madzaringwe formation Soutpansberg Coalfield

Effect of drug therapies on self-reported chemosensory outcomes after COVID-19

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 88-96页

作者： marco A.Fornazieri bruno m.Cunha Samuel P.Nicácio Lucas K.Anzolin JoséL.b.da Silva Aristides Fernandes Neto Deusdedit brandão Neto Richard L.Voegels Fábio D.R.Pinna Department of Surgery Londrina State UniversityLondrinaBrazil Department of medicine Pontifical Catholic University of ParanáLondrinaBrazil Department of Otorhinolaryngology University of São PauloSao PauloBrazil Department of Otorhinolaryngology:Head and Neck Surgery Perelman School of MedicineSmell and Taste CenterUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA

Objective:The aim of this study was to assess the relative efficacy of medications used following severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection on self-reported alterations in taste and/or smell ***:Seven hundred and fourteen persons with self-reported postcoronavirus disease 2019(post-COVID-19)chemosensory disorders were personally interviewed regarding specific medications they were administered following the acute phase of the *** dependent measure—self-reported total recovery of chemosensory symptoms—was subjected to stepwise logistic *** predictors included demographic and clinical variables,in addition to specific medications used to mitigate disease symptoms(i.e.,systemic corticosteroids,oseltamivir,vitamin C,ibuprofen,hydroxychloroquine,azithromycin,ivermectin,nitazoxanide,anticoagulants,and zinc).Results:The median time between COVID-19 symptom onset and the interviews was 81 days(interquartile range:60-104).Of the 714 subjects,249(34.9%)reported total recovery of their chemosensory function;437(61.2%)had at least one treatment since the beginning of the *** and those with more comorbidities had undergone more *** recovery rates of the treated and nontreated groups did not differ ***,respondents who had used nitazoxanide tended to have a higher rate of self-reported taste or smell *** who took oral zinc were less likely to ***:No medication employed during the first months after SARS-CoV-2 infection had a clear positive effect on returning self-reported smell or taste function to normal,although nitrazoxide trended in a positive *** zinc had a negative effect on the reported recovery of these senses.

关键词： chemosensory disorder coronavirus infections COVID-19 drug therapy SARS-CoV-2 smell loss taste loss

Correcting distortions of thin-walled machined parts by machine hammer peening

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Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor mADARIAGA mikel CUESTA Gorka ORTIZ-DE-ZARATE Eneko SAENZ-DE-ARGANDONA Denis SORIANO michael b.PRImE Pedro Jose ARRAZOLA Department of materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEm model was used to predict distortions caused by machining in a representative ***,the RS induced by hammer peening were included in an FEm model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 mPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics machining,Hammer Peening Aluminium alloy Distortions Residual Stress

Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green manure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark b. Neely Francis m. Rouquette Jr. Cristine L.S. morgan Frank m. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&m AgriLife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t Dm ha-1) and contributed the most total N (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea

关键词： Annual Legumes Soil N Soil Organic C Green manure Deer browse Forage Cropping Systems

biochemical Liver Functions and molecular Identification of Fasciola hepatica from Experimentally Infected Rat model

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Open Journal of Animal Sciences 2024年第2期14卷 88-100页

作者： Omnia m. Kandil Emad b. Ata margarita P. Gabrashanska Hatem A. Shalaby Tamer H. Abd El-Aziz Noha m. F. Hassan Soad m. Nasr mohamed A. Helal Ebtesam m. Al-Olayan Department of Parasitology & Animal Diseases Veterinary Research Institute National Research Centre Giza Egypt Institute of Experimental morphology Pathology and Anthropology with Museum Bulgarian Academy of Sciences Sofia Bulgaria Department of Zoology Collage of Science King Saud University Riyadh Saudi Arabia

The current study was performed to evaluate the liver function status as well as molecular characterization of the recovered worms in rats experimentally infected with F. hepatica. Sixteen male Wister rats aged 30 days were randomly allocated into two groups (n = 8). The first group was infected orally with 15 viable encysted metacercaria of F. hepatica per animal. The other group was kept non-infected (control group). At zero time (before infection), the 2nd, 4th, 6th, 8th, 10th, 12th and 14th weeks post-infection (WPI), blood and serum samples were collected via puncture of retro-orbital plexus of veins from each rat. Serum enzyme level (AST and ALT) and total protein were measured, and the serum protein profile was carried out using agarose gel electrophoresis. During the period of the experiment, serum ALT and AST activities and serum total globulins significantly increased while serum total proteins and albumin markedly decreased in the infected group. On the 14th WPI, the data of the electropherogram showed that globulin fractions (α1-, β- and γ-globulin) levels were significantly increased while α2-globulin was markedly decreased in the infected group. The molecular analysis confirmed the amplification of the ITS1, ITS2 and NDI genes of F. hepatica recovered from the infected liver of rats with amplicon sizes of 630, 510 and 560 bp, respectively. Sequencing of the amplified ITS gene resulted in the determination of 3 strains (PP108836, PP108837, and PP108838). Also, analysis of the ITS2 gene resulted in obtaining 3 isolates under the accession numbers (PP109065, PP109066, and PP109067). In conclusion, fasciolosis in the rat model is suitable for routine experimental infections and caused a pronounced liver dysfunction with discharging of the Fasciola eggs in the faeces and the development of adult stages in the bile ducts. Furthermore, molecular techniques are a sensitive

关键词： Fasciola hepatica Liver Functions Serum Enzymes Serum Protein Electrophoresis molecular Characterization

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang Y.Chen W.b.Yao C.Z.Xiao J.F.myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Fluoride contamination in groundwater:A global review of the status,processes,challenges,and remedial measures

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Geoscience Frontiers 2024年第2期15卷 1-29页

作者： E.Shaji K.V.Sarath m.Santosh P.K.Krishnaprasad b.K.Arya manisha S.babu Department of Geology University of KeralaKariavattom CampusThiruvananthapuramKerala 695581India School of Earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia Department of Geology Central University of KeralaTejaswini HillsPeriyeKasaragodKerala 671316India

Groundwater pollution by fluoride is one of the prime concerns of the world population due to its toxicity,which results in adverse health *** this paper,we review the current scenario of the fluoride contamination of groundwater in various countries across the globe and its impact on human *** the last decade,several newly affected regions have been reported all over the world,with more than 100 countries affected by fluoride contamination in groundwater(concentration exceeding the acceptable limit of 1.5 mg/L defined by the World Health Organization).Fluoride poisoning is mainly due to the unsupervised ingestion of products for dental and oral hygiene and over-fluoridated drinking *** is estimated that more than 200 million people from different countries are affected by fluoriderelated groundwater issues and health *** highest among these are from the countries in Africa(38),Asia(28),and Europe(24),followed by countries like South America(5),North America(3),and Australia(2).The source of fluoride in drinking water is primarily geogenic,together with forage,grasses and grains,tea,and anthropogenic *** countries affected were correlated with climatic zones and geological factors to gain insights into geospatial *** analyses show that most of the fluoride pollution-prone zones are located in high-grade metamorphic terranes with granitoid or alkaline intrusions,geothermal hot springs,and volcanic regions with arid or semi-arid climatic *** study also finds that children across the globe are more vulnerable than adults to fluoride *** review finds that,although there are efficient fluoride removal techniques,including filters with next-generation nanomaterials,to date,there has not been a single technique developed that can claim to be a practically robust solution for fluoride removal from drinking ***,we suggest developing next-generation filters that can retain essential miner

关键词： Fluoride Groundwater Water contamination WHO standards Climate zones Remediation Sustainable Development Goals

Ground-based and additional science support for SmILE

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Earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.Carter m.Dunlop C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.milan T.Sergienko R.C.Fear D.G.Sibeck m.Connors T.Yeoman X.Tan m.G.G.T.Taylor K.mcWilliams J.Gjerloev R.barnes D.D.billet G.Chisham A.Dimmock m.P.Freeman D.-S.Han m.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu m.K.James L.Juusola K.Kauristie E.A.Kronberg m.Lester J.manuel J.matzka I.mcCrea Y.miyoshi J.Rae L.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun m.-T.Walach b.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang Planetary Sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton Laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and Environment Beihang UniversityBeijing 100191China Key Laboratory of Space Environment monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 british Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard Space Flight Center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada ESTEC European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of China Shanghai 200136China Finnish meteorological Institute(FmI) Finland Department of Earth and Environmental Sciences(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada GFZ German Research Centre for Geosciences PotsdamGermany Nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria University Newcastle upon TyneTyne and WearUK NE18ST National Space Science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint European Space Agency and Chinese Academy of Sciences Solar wind magnetosphere Ionosphere Link Explorer(SmILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SmILE ***,we describe current community efforts to prepare for SmILE,and the benefits and context various experiments that have explicitly expressed support for SmILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these *** include constructing an online SmILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SmILE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SmILE conjunctions missions

Effect of neutral polymeric bonding agent on tensile mechanical properties and damage evolution of NEPE propellant

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Defence Technology（防务技术） 2024年第2期32卷 357-367页

作者： m.Wubuliaisan Yanqing Wu Xiao Hou Kun Yang Hongzheng Duan Xinmei Yin State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China The Fourth Institute of China Aerospace Science and Technology Corporation Xi'an710025PR China School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081PR China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechnologyHubei441003PR China

Introducing Neutral Polymeric bonding agents(NPbA) into the Nitrate Ester Plasticized Polyether(NEPE)propellant could improve the adhesion between filler/matrix interface, thereby contributing to the development of new generations of the NEPE propellant with better mechanical properties. Therefore,understanding the effects of NPbA on the deformation and damage evolution of the NEPE propellant is fundamental to material design and applications. This paper studies the uniaxial tensile and stress relaxation responses of the NEPE propellant with different amounts of NPbA. The damage evolution in terms of interface debonding is further investigated using a cohesive-zone model(CZm). Experimental results show that the initial modulus and strength of the NEPE propellant increase with the increasing amount of NPbA while the elongation decreases. meanwhile, the relaxation rate slows down and a higher long-term equilibrium modulus is reached. Experimental and numerical analyses indicate that interface debonding and crack propagation along filler-matrix interface are the dominant damage mechanism for the samples with a low amount of NPbA, while damage localization and crack advancement through the matrix are predominant for the ones with a high amount of NPbA. Finally, crosslinking density tests and simulation results also show that the effect of the bonding agent is interfacial rather than due to the overall crosslinking density change of the binder.

关键词： Solid propellant bonding agent mechanical properties Damage evolution Cohesive-zone model Interface debonding