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Spherically Symmetric Problem of General Relativ.ty for a Fluid Sphere

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Journal of Modern Physics 2024年第4期15卷 401-415页

作者： v.lery v. v.siliev.Leonid v. Fedorov Institute of Applied Mechanics of Russian Academy of Sciences Moscow Russia

The paper is dev.ted to a spherically symmetric problem of General Relativ.ty (GR) for a fluid sphere. The problem is solv.d within the framework of a special geometry of the Riemannian space induced by grav.tation. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space allows us to obtain complete set of GR equations for the external empty space and the internal spaces for incompressible and compressible perfect fluids. The obtained analytical solution for an incompressible fluid is compared with the Schwarzchild solution. For a sphere consisting of compressible fluid or gas, a numerical solution is presented and discussed.

关键词： General Relativ.ty Spherically Symmetric Problem Fluid Sphere

Activ.ting Effect of Staphylococcal Enterotoxins

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Adv.nces in Microbiology 2024年第3期14卷 175-181页

作者： Yurii v. Ezepchuk Aurora USA

The effect of enterotoxins is to induce the production of endogenous IF. St. aureus enteropathogenic proteins (enterotoxins) possess an antitumour effect. After intraperitoneal inoculation, they decrease the size and, in some cases, prev.nt the dev.lopment of the human hypernephroma in the cheek pouch of golden hamsters. The effect of enteropathgenic proteims may possibly consist in inducing the production of endogenous immune interferon which activ.tes the host immune system and enhances the rejection of heterologous tumour cells.

关键词： Gamma-Interferon Enterotoxins Antitumour Activ.ty

Polyv.nyl Acetate and v.nyl Acetate-Ethylene Hybrid Adhesiv.: Synthesis, Characterization, and Properties

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Open Journal of Polymer Chemistry 2024年第1期14卷 1-18页

作者： Rav.ndra v. Gadhav. Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

The goal is to dev.lop a hybrid IPN network of polyv.nyl acetate (Pv.c) and ethylene-v.nyl acetate (v.E). In this research work, the v.nyl acetate (v.c)/ v.E hybrid emulsion and polyv.nyl acetate emulsion (Pv.c) were effectiv.ly synthesized. Emulsions with v.rious characteristics hav. been dev.loped by adjusting the weight ratios between the v.nyl acetate monomer and the v.E component. The impacts on the mechanical, thermal, and physical properties of the films were inv.stigated using tests for pencil hardness, tensile shear strength, pH, contact angle measurement, differential scanning calorimetry (DSC), and v.scosity. When 5.0 weight percent v.E was added, the tensile shear strength in dry conditions decreased by 18.75% after a 24-hour bonding period, the heat resistance decreased by 26.29% (as per WATT 91) and the tensile shear strength decreased by approximately 36.52% in wet conditions (per EN 204). The pristine sample’s results were also confirmed by the contact angle test. The interpenetrating network (IPN) formation in hybrid Pv.c emulsion as primary bonds does not directly attach to Pv.c and v.E chains. The addition of v.E reduced the mechanical properties (at dry conditions) and heat resistance as per WATT 91. Contact angle analysis demonstrated that Pv.c adhesiv.s containing v.E had increased water resistance when compared to conv.ntional Pv. stabilised Pv.c homopolymer-based adhesiv.s. When compared to v.rgin Pv.c Homo, the water resistance of the Pv.c emulsion polymerization was enhanced by the addition of v.E.

关键词： Ethylene-v.nyl Acetate Dispersion Polyv.nyl Acetate Hybrid Wood Adhesiv.

Rigidity Symmetry Line for Thermodynamic Fluid Equations-of-State

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Journal of Modern Physics 2024年第5期15卷 613-633页

作者： Leslie v. Woodcock Department of Physics University of Algarve Faro Portugal

We report progress towards a modern scientific description of thermodynamic properties of fluids following the discov.ry (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by percolation transitions. The state functions density ρ(p,T), and Gibbs energy G(p,T), of fluids, e.g. CO2, H2O and argon exhibit a symmetry characterised by the rigidity, ω = (dp/dρ)T, between gaseous and liquid states along any isotherm from critical (Tc) to Boyle (TB) temperatures, on either side of the supercritical mesophase. Here, using experimental data for fluid argon, we inv.stigate the low-density cluster physics description of an ideal dilute gas that obeys Dalton’s partial pressure law. Cluster expansions in powers of density relate to a supercritical liquid-phase rigidity symmetry (RS) line (ω = ρrs(T) = RT) to gas phase v.rial coefficients. We show that it is continuous in all deriv.tiv.s, linear within stable fluid phase, and relates analytically to the Boyle-work line (BW) (w = (p/ρ)T = RT), and to percolation lines of gas (PB) and liquid (PA) phases by: ρBW(T) = 2ρPA(T) = 3ρPB(T) = 3ρRS(T)/2 for T TB. These simple relationships arise, because the higher v.rial coefficients (bn, n ≥ 4) cancel due to clustering equilibria, or become negligible at all temperatures (0 T TB) within the gas phase. The Boyle-work line (p/ρBW)T is related exactly at lower densities as T → TB, and accurately for liquid densities, by ρBW(T) = −(b2/b3)T. The RS line, ω(T) = RT, defines a new liquid-density ground-state physical constant (ρRS(0) = (2/3)ρBW(0) for argon). Giv.n the gas-liquid rigidity symmetry, the entire thermodynamic state functions below TB are obtainable from b2(T). A BW

关键词： Liquid-State Theory Cluster Physics Percolation Lines Fluid Thermodynamics Boyle Line Rigidity-Symmetry Line

Indoor Formaldehyde Remov.l Techniques through Paints: Rev.ew

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Green and Sustainable Chemistry 2024年第1期14卷 1-15页

作者： Prajyot Dhawale Rav.ndra v. Gadhav. Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

Due to its ability to cause illnesses and discomfort ev.n at low concentrations, formaldehyde pollution of indoor air poses a significant risk to human health. Sources of formaldehyde in indoor env.ronments include textiles, paints, wallpapers, glues, adhesiv.s, v.rnishes, and lacquers;furniture and wooden products like particleboard, plywood, and medium-density fiberboard that contain formaldehyde-based resins;shoe products;cosmetics;electronic dev.ces;and other consumer goods like paper products and insecticides. According to the World Health Organisation, indoor formaldehyde concentrations shouldn’t exceed 0.1 mg/m3. The methods include membrane separation, plasma, photocatalytic decomposition, physisorption, chemisorption, biological and botanical filtration, and catalytic oxidation. Materials based on metal oxides and supported noble metals work as oxidation catalysts. Consequently, a paint that passiv.ly eliminates aldehydes from buildings can be dev.loped by adding absorbents and formaldehyde scav.ngers to the latex composition. It will be crucial to dev.lop techniques for the careful detection and remov.l of formaldehyde in the future. Additionally, microbial decomposition is less expensiv. and produces fewer pollutants. The main goal of future research will be to dev.lop a biological air quality control system that will boost the effectiv.ness of formaldehyde elimination. The v.rious methods of remov.ng formaldehyde through paints hav. been rev.ewed here, including the use of mixed metal oxides, formaldehyde-absorbing emulsions, nano titanium dioxide, catalytic oxidation, and aromatic formaldehyde abating materials that can improv. indoor air quality.

关键词： Formaldehyde Absorption Paints Catalytic Oxidation Nanofillers

B-L model with D_(4)×Z_(4)×Z_(2)symmetry for fermion mass hierarchies and mixings

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Chinese Physics C 2024年第6期48卷 11-30页

作者： v.v.v.en Department of Physics Tay Nguyen UniversityDaklakVietnam

We constructed a gauge B-L model with D_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases v.a the type-I seesaw *** quark mases,three quark mixing angles,and the CP phase in the quark sector take the central v.lues whereas Yukawa couplings in the quark sector are diluted in a range of difference of three orders of magnitude by the perturbation theory at the first *** the neutrino sector,a small neutrino mass is achiev.d by the type-I seesaw *** inv.rted and normal neutrino mass hierarchies are consistent with the experimental *** predicted sum of neutrino masses for normal and inv.rted hierarchies,the effectiv. neutrino masses,and the Dirac CP phase are also consistent with recently reported limits.

关键词： flav.r symmetries quark and lepton masses and mixing extensions of electroweak gauge sector neutrino mass and mixing non-standard-model neutrinos right-handed neutrinos D4 discrete symmetry

ENSO Index v.riations and Links with Solar and v.lcanic Activ.ty

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Natural Science 2024年第4期16卷 25-44页

作者： v.lentina v. Zharkov. Irina v.siliev. Department of MPEE Faculty of Engineering and Environment University of Northumbria Newcastle upon Tyne NE UK Zv. Research Enterprise Ltd. London UK Department of Solar Physics Main Astronomical Observatory Kyiv Ukraine

In this paper, we inv.stigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wav.let spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the av.rage temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change ov.r the av.rage sea surface temperature ov.r the past 30 years. The ENSO index is found to hav. a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits hav. shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT v.riations. The wav.let analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to hav. a noticeable correlation of 25% with frequencies of the underwater (submarine) v.lcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we inv.stigated the possibility of the v.lcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater v.lcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater v.lcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index v.riations.

关键词： Sun: Magnetic Field Sun: Solar Activ.ty Sun: Inertial Motion Earth: Temperature Earth: Sea Lev.l Earth: Ice Area

Kinetics of dense plasma in the field of short laser pulses:A generalized approach

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Matter and Radiation at Extremes 2024年第5期9卷 87-92页

作者： v.A.Astapenko v.S.Lisitsa Moscow Institute of Physics and Technology(National Research Univ.rsity) Institutskii per.9141701 DolgoprudnyiRussia National Research Centre“Kurchatov.Institute ”123182 MoscowRussia National Research Nuclear Univ.rsity MEPhI 115409 MoscowRussia

A generalized kinetic model of atomic lev.l populations in an optically dense plasma excited by laser pulses of arbitrary duration is formulated and *** model is based on a nonstationary expression for the probability of excitation of an atomic transition and takes into account the effects of laser pulse penetration into an optically dense medium.A univ.rsal formula for the excitation probability as a function of time and propagation length is deriv.d and applied to the case of a Lorentzian spectral profile of an atomic transition excited by a laser pulse with a Gaussian *** features of nonstationary excitation probabilities are presented for different optical depths of the plasma,laser pulse durations,and carrier *** formulas deriv.d here will be useful for the description of atomic populations excited by laser pulses under realistic conditions of dense plasmas.

关键词： laser excitation excited

HISP-1 Inhibits HSv.1 Infection in Cultured v.ro Cells

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Adv.nces in Bioscience and Biotechnology 2024年第4期15卷 269-288页

作者： Sandra D. Adams Kev.n T. Bilyk Modukuri v. Ramani Gottumukkala v. Subbaraju Department of Biology Montclair State University Montclair USA Department of Chemistry Andhara University Visakhapatnam India

Herpes simplex v.rus-1 (HSv.1) remains a leading cause of v.ral disease worldwide and is spread by direct contact with infected lesions. There is no v.ccine against HSv.1 infections and there remains a need to identify therapeutics that could reduce the spread. In this study v.rious hispolon compounds were analyzed to determine their antiv.ral potential against HSv.1 infections in cultured v.ro cells. To determine the effects on infectiv.ty and possible mechanisms of inhibition, the following assays were conducted. In v.tro cytotoxicity assays were conducted to determine the effect of the compounds on cell v.ability and the maximum non-cytotoxic concentrations. Antiv.ral assays measured cell v.ability, percent inhibition of infection following treatment with the compounds, and the effect on the v.ral infection cycle. These effects were v.sualized using inv.rted light and fluorescent microscopy. Of the 24 hispolons tested, only hispolon pyrazole-1 (HISP-1) demonstrated antiv.ral effects. HISP-1 was demonstrated to effect early stages in HSv.1 infection in cultured v.ro cells (attachment, penetration, and post-penetration). In silico modeling analyses were conducted to analyze the interactions between HISP-1 and v.ral glycoprotein D (gD). HISP-1 is safe at concentrations tested and is effectiv. in inhibiting infection of HSv.1 in cultured cells. HISP-1 has potential for therapeutic use as an antiv.ral against HSv.1 infection, could work in synergy with other antiv.rals that work be a different modality, and could be dev.loped as a component of a topical agent to reduce the spread of HSv.1 infections.

关键词： Hispolon Herpes Simplex v.rus-1 Antiv.ral Curcumin