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Design of Biologically Active Macromolecular ligands and Their luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana N.Nekrasova Andrei I.Fischer Natalia A.Nesterova Anatoliy v.Dobrodumov Anzhelika v.Garshinina Olga D.Shuvaeva Natalya v.Zakharova Evgenii F.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(N-vinylpyrrolidone(vP),N-methyl-N-vinylacetamide(MvAA),N-methacryloyl glucosamine(MAG))and anionic comononer sodium styrene sulfonate(NaSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing N-vinylamide units(vP,MvAA)is three times more intense than that observed for the complexes between Tb^(3+)and MAG-containing *** the case of NaSS-containing copolymers,the luminescence intensity is controlled by the values of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.

关键词： luminescence Water-soluble copolymers lanthanide complexes Antiviral activity Cytotoxicity

Enhanced saturation magnetization in la^(3+) doped NiCo ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli vidyasagar Thopudurthy Krishna Reddy C.v. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Government PolytechnicRayachotiA.P516269India

lanthanum doped nickel-cobalt nano ferrites with chemical formula Ni_(0.5)Co_(0.5)laxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by X-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of la *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FESEM) and agglomerated irregular grains are observed with increase of the rare earth element la ***-dispersive X-ray spectroscopy(EDX) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTIR) spectrum indicates the formation of the spinel ferrite structure with M-O *** direct band measurements from ultraviolet-visible spectroscopy(Uv-vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 ev for x=0.05 to x=0.15,then increases to 1.28 ev for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(vSM).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites Sol-gel auto combustion la doping Magnetic properties Rare earths

Wormhole solutions under the effect of dark matter in f(R,l_(m))gravity

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Communications in Theoretical Physics 2024年第5期76卷 102-113页

作者： lakhan v Jaybhaye Moreshwar Tayde PK Sahoo Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In the background of f(R,l_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo *** current study aims to accomplish these goals by examining various dark matter profiles including universal rotation curves(URC),Navarro-Frenk-White(NFW)model-Ⅰ,and NFW model-Ⅱinside two distinct f(R,l_(m))gravity *** to the f(R,l_(m))=R/2+l^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting the wormhole geometries with appropriate choice of free *** addition,to examine DM profiles under the f(R,l_(m))=R/2+(1+λR)l_(m) model,we consider a specific shape ***,we observed that the derived solution from both two models violates the null energy constraints,confirming that the DM supports wormholes to maintain in the galactic halo.

关键词： f(R l_(m))gravity wormhole dark matter(Some figures may appear in colour only in the online journal)

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

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Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： Natalya v.Zakharova Stanislav N.Zelinskiy Mariya S.Strelova Elena N.Danilovtseva vadim v.Annenkov Institute of Macromolecular Compounds of the Russian Academy of Sciences Saint Petersburg199004Russia limnological Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Extracellular vesicles-coupled miRNAs from oviduct and uterus modulate signaling pathways related to lipid metabolism and bovine early embryo development

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1528-1549页

作者： Rosane Mazzarella Karina Canon‑Beltran Yulia N.Cajas Meriem Hamdi Encina M.Gonzalez Juliano C.da Silveira Claudia l.v.leal D.Rizos Department of Animal Reproduction INIA-CSICMadridSpain Department of Biochemistry and Molecular Biology Veterinary FacultyComplutense University of Madrid(UCM)MadridSpain Department Agrarian Production Technical University of MadridUPMMadridSpain Departamento de Ciencias Biologicas Universidad Tecnica Particular de LojaUTPLLojaEcuador Department of Anatomy and Embryology FV-UCMMadridSpain Department of veterinary Medicine FZEA-USPPirassunungaBrazil

Background Extracellular vesicles(Evs) present in oviductal(OF) and uterine fluid(UF) have been shown to enhance bovine embryo quality during in vitro culture by reducing lipid contents and modulating lipid metabolism-related genes(lMGs), while also influencing cell proliferation, suggesting their involvement on the regulation of different biological pathways. The regulation of signaling pathways related to cell differentiation, proliferation, and metabo-lism is crucial for early embryo development and can determine the success or failure of the pregnancy. Bioactive molecules within Evs in maternal reproductive fluids, such as micro RNAs(miRNAs), may contribute to this regulatory process as they modulate gene expression through post-transcriptional *** This study evaluated miRNA cargo in OF-Evs from the early luteal phase and UF-Evs from the mid-luteal phase, coinciding with embryo transit within oviduct and uterus in vivo, and its possible influence on lMGs and sign-aling pathways crucial for early embryo development. A total of 333 miRNAs were detected, with 11 exclusive to OF, 59 to UF, and 263 were common between both groups. From the 20 differentially expressed miRNAs, 19 up-regulated in UF-Evs(bta-miR-134, bta-miR-151-3p, bta-miR-155, bta-miR-188, bta-miR-181b, bta-miR-181d, bta-miR-224, bta-miR-23b-3p, bta-miR-24-3p, bta-miR-27a-3p, bta-miR-29a, bta-miR-324, bta-miR-326, bta-miR-345-3p, bta-miR-410, bta-miR-652, bta-miR-677, bta-miR-873 and bta-miR-708) and one(bta-miR-148b) in OF-Evs. These miRNAs were predicted to modulate several pathways such as Wnt, Hippo, MAPK, and lipid metabolism and degradation. Differ-ences in miRNAs found in OF-Evs from the early luteal phase and UF-Evs from mid-luteal phase may reflect differ-ent environments to meet the changing needs of the embryo. Additionally, miRNAs may be involved, particularly in the uterus, in the regulation of embryo lipid metabolism, immune system, and *** Our study su

关键词： Embryo-maternal interaction Epigenetic Exosomes Mammalian Preimplantation Reproductive fluids

Exploring the potential of drill cuttings for reservoir characterization:A case study from the volga-Ural basin,Russia

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Petroleum Research 2024年第2期9卷 193-205页

作者： Ibrahem Yousef v.P.Morozov Kazan Federal University Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectives are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reservoir *** cutting samples were collected from a vertical well that penetrated the Domanik sediments(Semiluksk Formation)in one of the oil fields in the volga-Ural petroleum *** sections from drill cuttings were examined using an optical polarizing microscope(Axio Imager A2).X-ray diffraction(XRD)analyses were performed using a Brucker D2 Phaser X-ray powder *** properties were studied using an STA 449 F3 Jupiter *** pyrolytic studies were performed using the Rock-Eval *** inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations revealed that the carbonates are mainly limestone(mudstone and wackestone)and are characterized by a dense texture and up to 30%organic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rocks are mainly composed of calcite,dolomite,quartz,feldspar,and mica,which are minor *** siliceous-carbonate rocks are dominated by quartz,followed by calcite,although they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6%(for the core samples)and 11.5%(for the drill cutting samples).The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,average S1 is 4.4 mg/g and average S2 is 19.8 mg/g(for the core samples);average S1 is 2.1 mg/g and average S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reservoir characterization Domanik Semiluksk volga-Ural Russia

ChatGPT: Application in Chemistry Education and Challenges

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Journal of Computer and Communications 2024年第3期12卷 196-206页

作者： vladimir l. Kodkin Ekaterina v. Artem’eva Power Engineering Faculty South Ural State University Chelyabinsk Russia Department of Chemistry Institute of Natural Sciences South Ural State University Chelyabinsk Russia

The paper discusses the advancements and applications of neural networks, specifically ChatGPT, in various fields, including chemistry education and research. It examines the benefits of AI and ChatGPT, such as their ability to process and analyze large amounts of data, create personalized training systems, and offer problem-solving recommendations. The paper delves into practical applications, showcasing how ChatGPT can be utilised to augment chemistry learning. It provides examples of using ChatGPT for creating tests, generating multiple-choice questions, and studying chemistry in general. Concerns are voiced about the ethical and societal impact of AI development. In conclusion, it explores the exciting potential of AI to tackle challenges that may exceed human capabilities alone, paving the way for further exploration and collaboration between humans and intelligent machines.

关键词： ChatGPT 3.5 Artificial Intelligence AI for Education Computer-Based learning

Preface–Introduction to the Special Issue for Chinese-Russian Workshop on Biophotonics and Biomedical Optics

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 1-3页

作者： Tingting Yu Dan Zhu valery v.Tuchin Britton Chance Center for Biomedical Photonics-MoE Key laboratory for Biomedical Photonics Advanced Biomedical Imaging FacilityWuhan National Laboratory for Optoelectronics–Advanced Biomedical Imaging FacilityHuazhong University of Science and TechnologyWuhan 430074China Department of Optics and Biophotonics Science Medical CenterSaratov State UniversitySaratov 410012Russia laboratory of laser Diagnostics of Technical and living Systems Institute of Precision Mechanics and ControlFRC“Saratov Scientic Centre of the Russian Academy of Sciences”Saratov 410028Russia laboratory of laser Molecular Imaging and Machine learning Tomsk State UniversityTomsk 634050Russia

The Chinese-Russian Workshop on Biophotonics and Biomedical Optics 2023 was held online twice on 18–21 September and 25–26 September *** bilateral workshop brought together both Russian and Chinese scientists,engineers,and clinical researchers from a variety of disciplines engaged in applying optical science,photonics,and imaging technologies to problems in biology and *** the workshops,two plenary lectures and twenty invited presentations were *** special issue selects some papers from both Russian and Chinese sides,consisting of one review and seven original research articles.

关键词： Russian photonics Biomedical

Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZlOv Ekaterina v.lEBEDEvA Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： volcanic lakes Echolocation survey volcanism Gashydrotherms Kamchatka Kuril Islands