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Isochrone Fitting of Galactic Globular Clusters—Ⅵ.High-latitude Clusters NGC 5024 (M53),NGC 5053,NGC 5272 (M3),NGC 5466,and NGC7099 (M30)

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Research in Astronomy and Astrophysics 2024年第6期24卷 170-190页

作者： G.A.Gontcharov s.s.savchenko A.A.Marchuk C.J.Bonatto O.s.Ryutina M.Yu.Khovritchev v.B.Il'in A.v.Mosenkov D.M.Poliakov A.A.smirnov Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1St.Petersburg 196140Russia saint Petersburg state University Universitetskij pr.28St.Petersburg 198504Russia special Astrophysical Observatory Russian Academy of Sciences369167 Nizhnij ArkhyzRussia Departamento de Astronomia Instituto de FísicaUFRGSAv.Bento Gonçalves9500Porto AlegreRSBrazil saint Petersburg University of Aerospace Instrumentation Bol.Morskaya ul.67ASt.Petersburg 190000Russia Department of Physics and Astronomy Brigham Young UniversityN283 ESCProvoUT 84602USA

We fit various color–magnitude diagrams(CMDs) of the high-latitude Galactic globular clusters NGC 5024(M53),NGC 5053,NGC 5272(M3),NGC 5466,and NGC 7099(M30) by isochrones from the Dartmouth stellar Evolution Database and Bag of stellar Tracks and Isochrones for α–enrichment [α/Fe] = +*** the CMDs,we use data sets from Hubble space Telescope,Gaia,and other sources utilizing,at least,25 photometric filters for each *** obtain the following characteristics with their statistical uncertainties for NGC 5024,NGC 5053,NGC 5272,NGC 5466,and NGC 7099,respectively:metallicities [Fe/H] =-1.93 ± 0.02,-2.08 ± 0.03,-1.60 ± 0.02,-1.95 ± 0.02,and-2.07 ± 0.04 dex with their systematic uncertainty 0.1 dex;ages 13.00 ± 0.11,12.70 ± 0.11,11.63 ± 0.07,12.15 ± 0.11,and 12.80 ± 0.17 Gyr with their systematic uncertainty 0.8 Gyr;distances(systematic uncertainty added) 18.22 ± 0.06 ± 0.60,16.99 ± 0.06 ± 0.56,10.08 ± 0.04 ± 0.33,15.59 ±0.03 ± 0.51,and 8.29 ± 0.03 ± 0.27 kpc;reddenings E(B-v) = 0.023 ± 0.004,0.017 ± 0.004,0.023 ± 0.004,0.023 ± 0.003,and 0.045 ± 0.002 mag with their systematic uncertainty 0.01 mag;extinctions Av= 0.08 ± 0.01,0.06 ± 0.01,0.08 ± 0.01,0.08 ± 0.01,and 0.16 ± 0.01 mag with their systematic uncertainty 0.03 mag,which suggest the total Galactic extinction Av= 0.08 across the whole Galactic dust to extragalactic objects at the North Galactic *** horizontal branch morphology difference of these clusters is explained by their different metallicity,age,mass-loss efficiency,and loss of low-mass members in the evolution of the core-collapse cluster NGC 7099 and loose clusters NGC 5053 and NGC 5466.

关键词： (stars:)Hertzsprung Russell and C-M diagrams (IsM:)dust extinction (Galaxy:)globular clusters:general (Galaxy:)globular clusters:individual(NGC 5024,NGC 5053,NGC 5272,NGC 5466,NGC7099)

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Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry O.Kudryavtsev Yulia v.sotnikova vladislav A.stolyarov Timur v.Mufakharov valery v.vlasyuk Margarita L.Khabibullina Alexander G.Mikhailov Yulia v.Cherepkova special Astrophysical Observatory of the Russian Academy of sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(Nvss, FIRsT, RATAN-600), IR(WIsE),optical(Pan-sTARRs), Uv(GALEX), and X-ray(ROsAT, swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(sOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FsRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HsP) blazars from the 3HsP catalog and blazars from the TevCat catalog. The obtained groups demonstrate concordance with the BL Lac/FsRQ classification along with a continuous character of the change in the properties. The group of HsP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general

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Liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： sANDRO C.OLIvEIRA MARIA s.sOAREs BÁRBARA v.GONÇALvEs ANDREIA C.M.RODRIGUEs AMADEU M.v.M.sOAREs RITA G.sOBRAL NUNO F.sANTOs JAN NEDOMA PEDRO L.ALMEIDA CARLOs MARQUEs CICECO-Aveiro Institute of Materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3N Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CEsAM-Centre for Environmental and Marine studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3N-CENIMAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized *** is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we developed optical immunosensors for the selective detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal molecules by using DMOAP during *** presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关键词： crystal alignment analysis

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Plasma electrolytic formation and characterization of MnWO_(4)/WO_(3) film heterostructures

ChemPhysMater

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ChemPhysMater 2024年第3期3卷 293-302页

作者： M.s.vasilyeva I.v.Lukiyanchuk Yu.B.Budnikova v.G.Kuryavyi D.H.shlyk G.A.Zverev Department of Chemistry and Materials of Institute of High Technology and Advanced Materials Far Eastern Federal UniversityFEFU CampusVladivostok 690922Russia Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia

MnWO_(4)/WO_(3) p-n heterojunction films were fabricated using a one-step method consisting of the plasma electrolytic oxidation(PEO)of titanium in homogeneous electrolytes containing paratungstate ions and stable watersoluble EDTA-chelated *** influences of the formation current density and W:Mn molar ratio of the electrolyte,which was varied from 1:2 to 2:1,on the composition,morphology,and optical and photocatalytic properties of the resulting coatings were studied.X-ray diffraction analysis,scanning electron microscopy,energy dispersive X-ray analysis,Raman spectroscopy,and ultraviolet diffuse reflectance spectroscopy were used to characterize the formed *** of the W:Mn ratio of the electrolyte,the coatings contained crystalline t-WO_(3) and m-MnWO_(4).Depending on the formation conditions,the optical band gap energies of the composites varied from 2.63 to 3.01 *** largest absorption red shift and lowest band gap energy were observed in the film composite formed in an electrolyte with W:Mn=2:1,at a current density of 0.2 A cm^(−2).Composites obtained in electrolytes with W:Mn ratios of 2:1 and 1:1 exhibited photocatalytic activity in the degradation of rhodamine C and methyl orange dyes in the presence of 10 mmol L^(–1) H2O_(2) under ultraviolet and visible light *** role of hydrogen peroxide in this dye degradation on PEO-coated composites under light irradiation is discussed.

关键词： Plasma electrolytic oxidation Manganese tungstate Tungsten oxide Titanium Optical properties p-n heterojunction

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Highly Defective Dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.D.Fakhrutdinova O.A.Reutova T.A.Bugrova I.Yu.Ovsyuk L.s.Kibis O.A.stonkus D.B.vasilchenko O.v.vodyankina v.A.svetlychnyi National Research Tomsk state University TomskRussia 634050 Novosibirsk state University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (sMsI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the sMsI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

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Effects of the level and source of dietary physically effective fiber on feed intake, nutrient utilization, heat energy, ruminal fermentation,and milk production by Alpine goats

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Animal Nutrition 2024年第2期17卷 312-324页

作者： Raquel v.Lourencon Amlan K.Patra Luana P.s.Ribeiro Ryszard Puchala Wei Wang Terry A.Gipson Arthur L.Goetsch American Institute for Goat Research Langston University

Thirty-two primiparous and 31 multiparous Alpine goats were used to determine influences of diets varying in level and source of forage on performance in early to mid-lactation for 16 wk. Diets consisted of 40%, 50%, 60%, and 70% forage(designated as 40F, 50F, 60F, and 70F, respectively) with 60F and 70F containing coarsely ground grass hay(primarily orchardgrass) and 40F and 50F containing cottonseed hulls, alfalfa pellets, and coarsely ground wheat hay. Diets contained 15.9% to 16.3% crude protein and37.8%, 42.1%, 53.5%, and 55.4% neutral detergent fiber(NDF) with 10.0%, 15.8%, 50.1%, and 55.5% particle retention on a 19-mm sieve, and 26.1%, 29.6%, 38.3%, and 40.0% physically effective NDF(pe NDF) for 40F,50F, 60F, and 70F, respectively. Dry matter intake(2.71, 2.75, 1.96, and 1.95 kg/d) and milk yield(2.82,2.71, 2.23, and 2.10 kg/d for 40F, 50F, 60F, and 70F, respectively) were lower(P s highest in forage. Digestion of organic matter was similar among diets(P > 0.05), but digestibility of NDF was greater(P spectively). Diet affected(P s(2.62%, 2.69%, 2.58%, and 2.52% for 40F, 50F, 60F, and 70F, respectively). Milk energy yield was greater(P s lowest in forage(7.51, 7.45, 5.68, and 5.34 MJ/d), although yield relative to dry matter intake was not affected(P > 0.05) by diet and was lower(P s vs. multiparous goats(2.71 and 3.09 MJ/kg). Ruminal p H and acetate proportion were greater for 60F and 70F than for the other diets and the proportion of butyrate was lower for the two diets highest in fiber. The mean lengths of time spent ruminating, eating, standing, and lying were not affected(P > 0.05) by diet or parity, but many interactions involving diet, period, hour, and parity were significant(P sion, lactational performance o

关键词： Physically effective fiber Alpine goat Lactation Ruminal fermentation Feeding behavior

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Going straight for the gut:gut-brain axis pathology and treatment of Parkinson's disease

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Neural Regeneration Research 2024年第10期19卷 2111-2112页

作者： Dominique Ebedes Cesar v.Borlongan University of south Florida Morsani College of Medicine TampaFLUSA Center of Excellence for Aging and Brain Repair Department of Neurosurgery and Brain RepairUniversity of South Florida Morsani College of MedicineTampaFLUSA

This perspective focuses on the recent literature regarding the role of the gut-brain axis(GBA) in fecal microbiota transplantation(FMT) and stem cell therapy(sCT) in Parkinson's disease(PD).PD is the second most common neurodegenerative disease in the United states,yet therapies remain *** research suggests that the GBA may play a role in the pathogenesis of *** FMT as well as sCT offer promising new avenues for PD *** bing the interactions between FMT and sCT with the GBA may reveal novel therapeutics for PD.

关键词： straight pathology pathogenesis

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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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Prompt neutron emission in ^(250)No spontaneous fission associated with ground and isomeric state decays

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Chinese Physics C 2024年第6期48卷 112-117页

作者： R.s.Mukhin A.v.Isaev A.v.Andreev M.L.Chelnokov v.I.Chepigin H.M.Devaraja I.N.Izosimov A.A.Kuznetsova O.N.Malyshev A.G.Popeko Yu.A.Popov A.Rahmatinejad B.sailaubekov T.M.shneidman E.A.sokol A.I.svirikhin M.s.Tezekbayeva M.A.Bychkov A.v.Yeremin O.Dorvaux B.Gall K.Kessaci K.Hauschild A.Lopez-Martens Joint Institute for Nuclear Research Dubna141980Russia Dubna state University Dubna141982Russia Institute of Nuclear Physics Almaty050032Kazakhstan L.N.Gumilyov Eurasian National University Astana010008Kazakhstan Kazan Federal University Kazan420008Russia Universitéde strasbourg CNRSStrasbourg67000France IJCLab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)Pb(^(48)Ca,2n)^(250)No was used to study two activities of^(250)No with distinct half-lives.A total of 1357 events were observed in the sFiNx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)No was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and K-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide

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Wood anatomy chronologies of scots pine in the foothills of the Western sayan(siberia)

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Journal of Forestry Research 2024年第3期35卷 13-27页

作者： Elena A.Babushkina Dmitry R.Dergunov Mikhail s.Zharkov Liliana v.Belokopytova Dina F.Zhirnova Bao Yang Jingjing Liu Xiaomei Peng Eugene A.vaganov Khakass Technical Institute Siberian Federal UniversityAbakan 655017Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China school of Geographic and Oceanographic sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological advances in quantitative wood anatomy have provided new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a novel approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, scots pine(Pinus sylvestris L.)trees > 200 years old were selected within the forest-steppe zone in southern siberia. such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum values of cell radial diameter and cell wall thickness were recorded for each tree *** a low level of climatogenic stress, components of cell chronologies independent of cambial activity were separated to obtain significant climatic signals revealing the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. secondary wall deposition lasted until mid-september, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and september compared with summer months.

关键词： Quantitative wood anatomy Cell radial size Cell wall thickness Pinus sylvestris Climatic response

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