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Ion-conducting Membranes Based on Bacterial Cellulose Nanofibers Modified by Poly(sodium acrylate-co-2-acrylamido-2-methylpropanesulfonic acid)

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Chinese Journal of Polymer Science 2024年第3期42卷 333-343,I0007页

作者： Elizaveta v.Batishcheva Nikolay N.Smirnov Natalya v.Bobrova Maria P.Sokolova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

Green method for preparation of ion-conducting membranes(ICM) based on bacterial cellulose nanofibers(CNF) modified by a copolymer of sodium acrylate and 2-acrylamido-2-methylpropanesulfonic acid was elaborated. FTIR and NMR data confirmed grafting of polyacrylate onto cellulose surface. Formation of porous structure of the ICM was controlled by SEM and AFM. The maximal ionic conductivity of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relative humidity) when they are saturated with water or H_2SO_4(1 mol·l^(-1)) electrolyte,respectively. Prepared ICM was tested as a separator in a symmetrical supercapacitor with electrodes based on polyaniline hydrogel. The assembled cell demonstrate ability to operate at high current density up to 100 A·g^(-1) maintaining specific capacitance 165 F·g^(-1). Maximal specific capacitance of 289 F·g^(-1) was achieved at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles proves high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductivity Porous membrane Supercapacitor

Magnetic methods in studies of new superconducting hydrides in a diamond anvil cell

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National Science Review 2024年第7期11卷 16-18页

作者： viktor v.Struzhkin Ho-kwang Mao Center for High Pressure Science&Technology Advanced Research

In recent years, we have witnessed great success in discoveries of high-transition-temperature（Tc） hydrides using high-pressure experiments. This has been achieved by creating metallic hydrogen‘alloys’ with other ...

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Observation about the Classical Electromagnetic Gauge Transformation and Its Quantum Correspondence

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Journal of Modern Physics 2024年第4期15卷 474-479页

作者： Gustavo v. lópez Jorge A. lizarraga Departamento de Física Universidad de Guadalajara Guadalajara Mexico

Using the landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transformation does not correspond to a one-dimensional unitary group transformation U(1) of the wave function for the quantum case. In addition, with the re-examination of the relation between the magnetic field B and its vector potential A, we found that, in order to have a consistent formulation of the dynamics of the charged particle with both expressions, we must have that B=∇×A if and only if B≠0.

关键词： Gauge Transformation Harmonic Oscillator Quantum Hall Effect Electromagnetic Potentials

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

Chronic Ankle Instability: Therapeutic Exercise and Data Analysis

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Open Journal of Orthopedics 2024年第5期14卷 201-217页

作者： rosa Grazia Bellomo Giulia Barletta Mirco Brunetti Claudia Barbato Department of Biomolecular Sciences University of Study of Urbino Carlo Bo Urbino Italy

Background and Objectives: Ankle injuries are the most common type of injury in healthy active individuals. If not treated properly, recurrent sprains can lead to a condition of chronic ankle instability (CAI). The present paper examines some subjects with a previous history of acute inversion ankle sprain who have developed a subsequent condition of instability, grouping them according to inclusion criteria and analyzing them through four field tests considered objective by the scientific literature: SEBT test, BEES test, TIBT test, SHT test. The data obtained were stored in order to compare them following a re-education protocol aimed at improving proprioception, balance, walking and strengthening the extrinsic and intrinsic muscles of the foot. per year. The subjects were then divided into two categories: subjects with CAI > 1 year and subjects with CAI ≤ 1 year. A protocol lasting 6 weeks was administered to both groups, trying to work on improving balance in single stance, improving static and dynamic stability, strengthening the gluteus medius and maximus (pelvis stabilizers) and strengthening of the intrinsic muscles of the foot. At the end of the protocol the subjects were all re-evaluated with the same field tests used previously and the data obtained were compared both with the pre-protocol data and with the data measured by the control subjects.

关键词： Ankle Instability Ankle Sprain Ankle Injuries Exercise

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