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Journal of Magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.V.Mashtalyar i.M.imshinetskiy V.V.kashepa K.V.Nadaraia M.A.Piatkova A.i.Pleshkova K.A.Fomenko A.Yu.Ustinov S.L.Sinebryukhov S.V.Gnedenkov institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on MA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

Microstructure， electrochemical， wear and corrosive wear performance of laser-based powder bed fusion(lpbf) and wrought biomedical Ti-6Al-4V alloys

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Transactions of Nonferrous Metals Society of China 2024年

作者： A.G.Lekatou B.V.Efremenko V.Haoui V.G.Efremenko S.Emmanouilidou V.i.Zurnadzhy i.Petryshynets Yu.G.Chabak i.i.Sili Laboratory of Applied Metallurgy， Department of Materials Science and Engineering， School of Engineering， University of ioannina institute of Materials Science and Computing， University Research Center of ioannina (URCi) Pryazovskyi State Technical University， Department of Physics institute of Materials Research of Slovak Academy of Sciences

Wrought and laser powder bed fusion （LPBF） Ti-6Al-4V specimens were comparatively evaluated， with the objective to determine LPBF Ti-6-4’s suitability for biomedical applications. Testing included nanoindentation， cyclic polarization in simulated body fluid （SBF， 37 ℃ ）， and dry and SBF “Ball-on-Plate” sliding. Wrought Ti-6-4 exhibited a lamellar （α+β） microstructure， whereas LPBF displayed a fine-grained α'-martensite microstructure. LPBF Ti-6-4 demonstrated ～3% higher indentation modulus and ～32% higher hardness， while wrought Ti-6-4 showed ～8% higher plasticity. Both alloys exhibited low corrosion rates (10–5mA/cm2order) and true passivity (10–4mA/cm2order). No localized corrosion was observed in either alloy， except for occasional metastable pitting in the LPBF alloy. However， LPBF Ti-6-4 presented higher corrosion rate and passive current， ascribed to its martensitic structure. During dry sliding， LPBF Ti-6-4 exhibited ～14% lower volume loss compared to wrought Ti-6-4. Sliding in SBF increased volume losses for both alloys， with wear resistances nearly equalized， as the advantage of LPBF Ti-6-4 decreased due to more intensive wear-accelerated corrosion induced by the stressed martensite. Overall， the results demonstrate the suitability of LPBF Ti-6Al-4V for biomedical uses.

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Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.V.Nadaraia D.V.Mashtalyar M.A.Piatkova A.i.Pleshkova i.M.imshinetskiy M.S.Gerasimenko E.A.Belov V.V.Kumeiko D.N.Kozyrev K.A.Fomenko V.V.Mostovaya B.R.Torpanov A.R.Biktimirov i.S.Osmushko S.L.Sinebryukhov S.V.Gnedenkov institute of Chemistry FEB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far Eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.V.Zhirmunsky National Scientific Center of Marine Biology FEB RAS 17 St.PalchevskogoVladivostok 690041Russia Regional Clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia NMiC“Treatment and Rehabilitation Center” 3 Ivankovskoe highwayMoscow 125367Russia

in this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were *** to SEM,EDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEO coatings was *** to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite Vancomycin

Sequential alkaline-organic acid leaching process to enhance the recovery of rare earth elements from indonesian coal fly ash

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Journal of Rare Earths 2024年第7期42卷 1366-1374,I0006页

作者： Widya Rosita indra Perdana i Made Bendiyasa Ferian Anggara Himawan Tri Bayu Murti Petrus Agus Prasetya isyatun Rodliyah Department of Nuclear Engineering and Engineering Physics Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Department of Chemical Engineering Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Department of Geological Engineering Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Unconventional Geo-resources Research Group Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Center for Testing of Mineral and Coal Tekmira-Directorate General of Mineral and Coal-Ministry of Energy and Mineral Resources Jl.Jend.Sudirman No.623Wr.MuncangKec.Bandung KulonKota BandungJawa Barat40211Indonesia

in this decade,coal fly ash(CFA)is considered a potential secondary source of rare earth elements(REEs).However,most REEs in coal fly ash are encapsulated in aluminosilicate glass,making it challenging to recover them through acid *** this study,a sequential alkaline-organic acid leaching was developed for the recovery of REEs from *** effect of alkaline leaching using NaOH solution on the destructive ability of aluminosilicate glass,as well as the mineralogy and morphology changes of the resulting coal fly ash,was first ***,the effectiveness of alkaline leaching on the recovery ability of REEs through organic acid leaching was *** results show that the maximum leaching efficiency for Si and Al,which was obtained at the optimum alkaline leaching conditions,namely NaOH concentration of 10 mol/L,reaction temperature of 65℃,liquid/solid(L/S)ratio of 10 mL/g,and reaction time of 90 min,is 28%and 32%,*** digestion reaction with NaOH lixiviants also causes coal fly ash to become more porous,making it advantageous in the organic acid-leaching process at the REEs recovery *** utilization of the desilicated residue produced from the digestion process in acid leaching effectively increases the overall REEs recovery from 32.2%to 77.6%.

关键词： Rare earth elements Alkaline Organic acid Coal fly ash

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The effect of climate factors on the size of forest wildfires(case study:Prague-East district,Czech Republic)

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Journal of Forestry Research 2022年第4期33卷 1291-1300页

作者： Zohreh Mohammadi Peter Lohmander Jan kašpar roman Berčák Jaroslav Holuša Robert Marušák Faculty of Forestry and Wood Sciences Czech University of Life Sciences PragueKamýcká12916500 Praha-SuchdolCzech Republic Optimal Solutions in Cooperation with Linnaeus University UmeaSweden

This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest *** linear regression was used in combination with nonlinear variable transformations to determine relevant nonlinear forest wildfire size *** from the Prague-East District of the Czech Republic was used for model *** burned forest area was hypothesized as a function of water vapor pressure,air temperature and wind *** speed was added to enhance predictions of the size of forest wildfires,and further improvements to the utility of prediction methods were added to the regression *** results show that if the air temperature increases,it may contain less water and the fuel will become *** size of the burned area then *** the relative humidity in the air increases and the wind speed decreases,the size of the burned area is *** model suggests that changes in the climate factors caused by ongoing climate change could cause significant changes in the size of wildfire in forests.

关键词： Climatic variables Burned forest area Climate change Multiple linear regression

Comparative analysis of jet and underlying event properties across various models as a function of charged particle multiplicity at 7 TeV

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Chinese Physics C 2024年第9期48卷 122-129页

作者： Maryam Waqar Haifa i.Alrebdi Muhammad Waqas K.S.Al-mugren Muhammad Ajaz Department of Physics Abdul Wali Khan University Mardan Department of Physics College of Science Princess Nourah bint Abdulrahman University School of Nuclear Science and Technology University of Chinese Academy of Sciences

in this study,a comprehensive analysis of jets and underlying events as a function of charged particle multiplicity in proton-proton（pp） collisions at a center-of-mass energy of s1/2=7 TeV is *** Monte Carlo（MC） event generators,including Pythia8.308,EPOS 1.99,EPOSLHC,EPOS4Hydro,and EPOS4noHydro,are employed to predict particle *** predictions from these models are compared with experimental data from the CMS *** charged particles are categorized into those associated with underlying events and those linked to jets,and the analysis is restricted to charged particles with |η| 0.25 GeV/*** comparing the MC predictions with CMS data,we find that EPOS4Hydro,EPOSLHC,and Pythia8 consistently reproduce the experimental results for all charged particles,underlying events,intrajets,and leading charged *** charged jet rates with ***> 5 GeV/c,EPOS4Hydroand Pythia8 perform exceptionally *** the case of charged jet rates with ***→30 GeV/c,EPOSLHC reproduces satisfactorily good results,whereas EPOS4 Hydro exhibits good agreement with the data at higher charged particle multiplicities compared to the other *** can be attributed to the conversion of energy into flow when "Hydro=on" leading to an increase in *** EPOSLHC model describes the data better owing to the new collective flow effects,correlated flow treatment,and parameterization compared to EPOS ***,the examination of the jet pTspectrum and normalized charged pTdensity reveals that EPOS4Hydro,EPOS4noHydro, and EPOSLHC exhibit good agreement with the experimental results,whereas Pythia8 and EPOS 1.99 do not perform as well owing to the lack of correlated flow treatment.

关键词： charged particle multiplicity jets Monte Carlo models underlying event

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 309-318页

作者： Ayşe E.ÖZSOYÖZBAY işıl SANRi kaRAPiNAR Zehra N.KUTLU ismail E.KiLiÇ Department of Civil Engineering Maltepe UniversityIstanbul 34857Turkey School of Engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inistanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin

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Energy Geoscience 2024年第1期5卷 12-23页

作者： ifeanyichukwu S.Obi K.Mosto Onuoha Chidozie i.Princeton Dim Mobil Producing Nigeria UnlimitedLagosNigeria Department of Geology University of NigeriaNsukkaEnugu StateNigeria

The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common *** the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the *** the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).in terms of bathymetry,it is noted that irrespective of systems tracts,the RSP index(Ri)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf *** all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest *** development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation *** is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand *** the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine *** seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the *** initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea *** approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volum

关键词： Reservoir-seal pairs(RSP) Systems tract Coastal swamp depobelt Bathymetry Sequence stratigraphy Niger Delta Basin

Exogenous testosterone therapy on choroid in androgen deficiency

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international Journal of Ophthalmology(English edition) 2024年第8期17卷 1489-1494页

作者： Volkan Yeter Nurullah Koçak Merve kalyoncu Ramazan Aşçi Nurşen Aritürk Department of Ophthalmology Ondokuz Mayıs UniversitySamsun 55139Turkey Department of Urology Ondokuz Mayıs UniversitySamsun 55139Turkey

AiM:To investigate the effects of exogenous testosterone treatment on the choroidal parameters in patients with androgen ***:Right eyes of 24 patients with androgen deficiency and 31 healthy volunteers were included in the *** eyes were scanned for subfoveal choroidal thickness(SFCT),choroidal vascularity index(CVi),choroidstromal area(C-SA),choroid-luminal area(C-LA),choroidstromal to luminal area ratio(CSLR),and the choroidal parameters within central 1500μm of the macula(CVi1500,C-LA1500,C-SA1500,and CSLR1500)by enhanced-depth imaging optical coherence tomography(EDi-OCT)at baseline,6th and 18th weeks of the exogenous testosterone ***:The mean SFCT values of the androgen deficient groups and healthy controls were 307.7±27.0 and 303.2±37.2μm(P=0.8).However,CVi,C-SA,CSLR,CVi1500,C-LA1500,and CSLR1500 were significantly different between the groups(all Pisit after exogenous testosterone treatment,SFCT,CVi,C-LA,and C-SA were significantly decreased,and these parameters returned to baseline levels at the 18th-week visit(all P>0.05).However,CVi1500 and LA1500 significantly increased at the end of the follow-up period(PiON:CVi is lower in androgen-deficient patients than in healthy *** alterations in the choroid during the testosterone peak are transient in the treatment of patients with androgen ***,the increase in CVi within the central 1500μm of the macula persists even after 4mo.

关键词： testosterone androgen deficiency choroid vascularity index

Britanin–a beacon of hope against gastrointestinal tumors?

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World Journal of Clinical Oncology 2024年第4期15卷 523-530页

作者： Agnieszka kajdanek Damian Kołat Lin-Yong Zhao Mateusz Kciuk Zbigniew Pasieka Żaneta kałuzińska-Kołat Department of Biomedicine and Experimental Surgery Medical University of LodzLodz 90-136LodzkiePoland Department of Functional Genomics Medical University of LodzLodz 90-752LodzkiePoland Department of General Surgery&Laboratory of Gastric Cancer State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Gastric Cancer Center West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Molecular Biotechnology and Genetics University of LodzLodz 90-237LodzkiePoland

Britanin is a bioactive sesquiterpene lactone known for its potent anti-inflammatory and anti-oxidant *** also exhibits significant anti-tumor activity,suppressing tumor growth in vitro and in *** current body of research on Britanin includes thirty papers predominantly related to neoplasms,the majority of which are gastrointestinal tumors that have not been summarized *** drive academic debate,the present paper reviews the available research on Britanin in gastrointestinal *** also outlines novel research directions using data not directly concerned with the digestive system,but which could be adopted in future gastrointestinal *** was found to counteract liver,colorectal,pancreatic,and gastric tumors,by regulating proliferation,apoptosis,autophagy,immune response,migration,and *** confirmed in pancreatic,gastric,and liver cancer,its most commonly noted molecular effects include nuclear factor kappa B and B-cell lymphoma 2 downregulation,as well as Bcl-2-associated X protein ***,it has been found to induce the Akt kinase and Forkhead box O1 axis,activate the AMP-activated protein kinase pathway,elevate interleukin-2 and peroxisome proliferator-activated receptor-γlevels,reduce interleukin-10,as well as downregulate matrix metalloproteinase-9,Twist family bHLH transcription factor 1,and *** also inhibits Myc–HiF1αinteraction and programmed death ligand 1 transcription by interrupting the Ras/RAF/MEK/ERK pathway and mTOR/P70S6K/4EBP1 *** research should aim to unravel the link between Britanin and acetylcholinesterase,mast cells,osteolysis,and ischemia,as compelling data have been provided by studies outside the gastrointestinal *** the cytotoxicity of Britanin on noncancerous cells is significantly lower than that on tumor cells,while still being effective against the latter,further in-depth studies with the use of animal models are *** compound exhi

关键词： Britanin Sesquiterpene lactones Chemotherapeutics Gastrointestinal tumors in vitro in vivo