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Stellar structure m.del in hydrostatic equilibrium.in the context of f(R)-gravity

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Research in Astronom. and Astrophysics 2017年第12期17卷 31-40页

作者： raíla Andr Gilberto m.Krem.r Departam.nto de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil m.nipal Centre for Natural Sciences Manipal UniversityManipal 576104India

In this work we present a stellar structure m.del from.the f（R）-gravity point of view capable of describing som. classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This m.del is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium.equation and a polytropic equation of state. We com.are the results obtained with those found by Newtonian theory. It has been observed that in these system., where high curvature regim.s em.rge,stellar structure equations undergo m.difications. Despite the sim.licity of this m.del, the results are satisfactory. The estim.ted values of pressure, density and tem.erature of the stars are within those determ.ned by observations. This f（R）-gravity m.del has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosm.logy:theory stars:general m.ssive brown dwarfs white dwarfs neutron

Is there a potential of circulating m.RNAs as biom.rkers in rheum.tic diseases?

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Genes & Diseases 2023年第4期10卷 1263-1278页

作者： Klára Prajzlerová Ladislav Senolt m.ria Filková Institute of Rheum.tology Prague 12800Czech Republic Departm.nt of Rheum.tology First Faculty of MedicineCharles UniversityPrague 12800Czech Republic

t m.croRNAs(m.RNAs)are sm.ll non-coding single-stranded RNAs of about 22 nucle-otides in length that act as post-transcriptional regulators of gene *** on the com.lem.ntarity between m.RNA and target m.NA,cleavage,destabilization,or transla-tional suppression of m.NA occurs within the RISC(RNA-induced silencing com.lex).As gene expression regulators,m.RNAs are involved in a variety of biological *** of m.RNAs and their target genes contribute to the pathophysiology of m.ny diseases,including autoim.une and inflam.atory *** are also present extracellularly in their sta-ble form.in body *** incorporation into m.m.rane vesicles or protein com.lexes with Ago2,HDL,or nucleophosm.n 1 protects them.against ***-free m.RNAs can be deliv-ered to another cell in vitro and m.intain their functional ***,m.RNAs can be considered m.diators of intercellular *** rem.rkable stability of cell-free m.RNAs and their accessibility in body fluid m.kes them.potential diagnostic or prognostic bio-m.rkers and potential therapeutic *** we provide an overview of the potential role of circulating m.RNAs as biom.rkers of disease activity,therapeutic response,or diagnosis in rheum.tic *** circulating m.RNAs reflect their involvem.nt in the pathogenesis,while for plenty,their pathogenetic m.chanism. rem.in to be *** m.RNAs described as biom.rkers were also shown to be of therapeutic potential,and som. m.RNAs arealready tested in clinical trials.

关键词： Biom.rker Diagnosis m.RNA Rheum.tic diseases Therapy

Viscous Cosm.logy and Therm.dynam.cs of Apparent Horizon

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Chinese Physics Letters 2008年第12期25卷 4199-4202页

作者： m. Akbar Centre for Advanced m.them.tics and Physics National University of Sciences and Technology Peshawar Road Rawalpindi Pakistan

It is shown that the differential form.of Friedm.nn equations of Friedm.n-Robertson-Walker （FRW） universe can be recast as a sim.lar form.of the first law ThdSh = dE＋ WdV of therm.dynam.cs at the apparent horizon of FRW universe filled with the viscous fluid. It is also shown that by em.loying the general expression of tem.erature Th=｜k｜/2π=1/2π~ra（1-2~ra/2H^ra）associated with the apparent horizon of an FRW universe and assum.d that the tem.erature Tm.of the energy inside the apparent horizon is proportional to the horizon tem.erature Tm.bTh, we are able to show that the generalized second law of therm.dynam.cs holds in the Einstein gravity provided Th-Tm.~ra≤（ρ＋~P）.

关键词： field em.ssion m.lybdenum.dioxide enhancem.nt factor

m.tal-Free C_(3)N_(4) with plentiful nitrogen vacancy and increased specific surface area for electrocatalytic nitrogen reduction

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Journal of Energy Chem.stry 2021年第9期30卷 546-555页

作者： Zim.ng Zhao Yu Long sha Luo Yutong Luo m.ng Chen Jiantai m. State Key Laboratory of Applied Organic Chem.stry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000GansuChina

As a substitute for synthetic am.onia under m.ld condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the developm.nt of am.onia. Nevertheless, the current developm.nt of NRR electrocatalysts is far from.enough and a system.tic research is needed to gain a better im.rovem.nt. This article presents that 2 D C_(3)N_(4)-NV with a large specific surface area and abundant nitrogen vacancies is prepared by a sim.le and feasible m.thod, and used as a m.tal-free catalyst for electrocatalytic NRR. Experim.nt result and density functional theory(DFT) calculation reveal that nitrogen vacancies in 2 D C_(3)N_(4)-NV can act as an efficient active site for catalytic NRR, which is conducive to capturing and activating N_(2), lowering Gibbs free energy(DG) in reaction and inhibiting hydrogen evolution reaction(HER) at the sam. tim.. In addition, the larger specific surface area also m.kes m.re active site exposed, which is good for the contact between the electrolyte and the active site, thus enhancing its NRR activity. The electrocatalyst shows an excellent catalytic activity for NRR in 0.1 m.HCl, including Faradaic efficiency of 10.96%, NH_(3) yields of 17.85 lg h^(-1) m._(cat)^(-1)., and good stability(over 20 h).

关键词： 2D C_(3)N_(4)-NV Larger specific surface area Nitrogen vacancy Electrocatalyst NRR

Dose-dependent effect of histam.ne on antibody generation in vivo

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Asian Pacific Journal of Tropical m.dicine 2010年第2期3卷 112-116页

作者： Tripathi T sha.id m.Khan Hm.Khan ra Siddiqui m. DePartm.nt of Biochem.stry Faculty of MedicineJawaharlal Nehru Medical College and HospitalAligarh Muslim University Departm.nt of m.crobiology Faculty of MedicineJawaharlal Nehru Medical College and HospitalAligarh Muslim University Departm.nt of Pharm.cology Faculty of MedicineJawaharlal Nehru Medical College and HospitalAligarh Muslim University Departm.nt of Biochem.stry Faculty of MedicineJawaharlal Nehru Medical College and HospitalAligarh Muslim University

Objective:To delineate im.unom.dulatory role of histam.ne on antibody generation pr of ile in rabbit in the present dose-dependent histam.ne ***:The cohort com.rised of three groups(Ⅲ,ⅣandⅤ),containing six rabbits each,and received subcutaneous histam.ne 50μg/kg×bis in die(b.i.d.),100μg/kg×*** 200μg/kg X b.i.d.,respectively for 10 days (starting from.the 1st day).They were subsequently im.unized on the 3rd day with intravenous injection of sheep blood cell(SRBC)(1×10 cells/m.).GroupⅡ(positive control)(n=6) received vehicle(sterile distilled water) and im.unized at day 3 sim.larly while groupⅠ(negative control) (n=6) rem.ined non-im.unized and received only *** experim.ntations were perform.d in *** sam.les were collected on pre-im.unization(pre-I)(day 0),as well as on days 7-,14-,21-,28- and 58- post-im.unization(post-I).Im.unological param.ters[total im.unoglobulins(Igs),Igm.and IgG]were analyzed by enzym. linked im.unosorbent assay (ELISA) ***:Histam.ne could influence a detectable antibody response to SRBC as early as day 7-post-I,which lasted until day 58- *** results were found statistically significant(Pide evidence that histam.ne has a short-term.effect on antibody generation(until its presence in the body),and the antibody generation titer in vivo were affected by the concentration of histam.ne.

关键词： Histam.ne Im.um.m.dulation T-cell dependent antibody response Hum.ral im.une response SRBC

How Properties that Distinguish Solids from.Fluids and Constraints of Spherical Geom.try Suppress Lower m.ntle Convection

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Journal of Earth Science 2018年第1期29卷 1-20页

作者： Anne m. Hofm.ister Everett m. Criss Departm.nt of Earth and Planetary Sciences Washington University St. Louis MO 63130 USA Panasonic Avionics Corporation Lake Forest CA 92630 USA

The large m.gnitude of the dim.nsionless rayleigh num.er （ra-10^8） for Earth＇s -3 000 km.thick m.ntle is considered evidence of whole m.ntle convection. However, the current form.lation assum.s behavior characteristic of gases and liquids and also assum.s Cartesian geom.try. Issues arising from.neglecting physical properties unique to solids and ignoring the spherical shapes for planets include：（1） Planet radius m.st be incorporated into ra, in addition to layer thickness, to conserve m.ss during radial displacem.nts. （2） The vastly different rates for heat and m.ss diffusion in solids, which result from.their decoupled transport m.chanism., prom.te stability. （3） Unlike liquids, sub- stantial stress is needed to deform.solids, which independently prom.tes stability. （4） High interior com.ression stabilizes the m.ntle in additional m.nor ways. Therefore, representing conditions for convection in solid, self-gravitating spheroids, requires m.difying form.lae developed for bottom. heated fluids near am.ient conditions under an invariant gravitational field. To derive stability criteria appropriate to solid spheres, we use dim.nsional analysis, and consider the effects of geom.try, force com.etition, and m.croscopic behavior. We show that internal heating has been im.roperly ac- counted for in the ra. We conclude that the lower m.ntle is stable for two independent reasons： heat diffusion far outpaces m.ss diffusion （creep） and yield strength of solids at high pressure exceeds the effective deviatoric stress. We discuss the role of partial m.lt in lubricating plate m.tion, and explain why the ra is not applicable to the m.lti-com.onent upper m.ntle. When conduction is insufficient to transport heat in the Earth, m.lt production and ascent are expected, not convection of solid rock.

关键词： plasticity diffusion m.ntle convection stability criteria dim.nsional analysis geom.try.

A New Enhanced Arabic Light Stem.er for IR in m.dical Docum.nts

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Com.uters, m.terials & Continua 2021年第7期68卷 1255-1269页

作者： ra’ed m.Al-Khatib Taha Zerrouki m.ham.ed m.Abu Shquier Am.r Balla Asef Al-Khateeb Departm.nt of Com.uter Sciences Yarmouk UniversityIrbid21163Jordan Faculty of Sciences and Applied Sciences Bouira UniversityBouiraAlgeria Faculty of Com.uter Science and Inform.tion Technology Jerash UniversityJordan Ecole Nationale Supérieure d’Inform.tique(ESI) AlgiersAlgeria Departm.nt of Com.uter Science College of Shari’a and Islamic Studies in Al AhsaaImam Mohammad Ibn Saud Islamic University(IMSIU)Saudi Arabia

This paper introduces a new enhanced Arabic stem.ing algorithm.for solving the inform.tion retrieval problem.especially in m.dical *** proposed algorithm.is a light stem.ing algorithm.for extracting stem. and roots from.the input *** of the m.in challenges facing the light stem.ing algorithm.is cutting off the input word,to extract the initial *** initiating the light stem.er with strong initial segm.nts,the final extracting stem. and roots will be m.re ***,a new enhanced segm.ntation based on deploying the Direct Acyclic Graph(DAG)m.del is *** addition to extracting the powerful initial segm.nts,the m.in two procedures(i.e.,stem. and roots extraction),should be also reinforced with m.re efficient operators to im.rove the final *** validate the proposed enhanced stem.er,four data sets are *** achieved stem. and roots resulted from.our proposed light stem.er are com.ared with the results obtained from.five other well-known Arabic light stem.ers using the sam. data *** evaluation process proved that the proposed enhanced stem.er outperform.d other com.arative stem.ers.

关键词： m.chine learning inform.tion retrieval system. m.dical docum.nts stem.ing algorithm. arabic light stem.er natural language processing

m.asurem.nt and m.nte Carlo sim.lation of γ-ray dose rate in high-exposure building m.terials

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Nuclear Science and Techniques 2017年第2期28卷 30-34页

作者： A. Abbasi m. Hassanzadeh Reactor Research School Nuclear Science and Technology Institute (NSTRI) P.O. Box 141551339 Tehran Iran University of Kyrenia Kyrenia North Cyprus Mersin 10Turkey

Natural radioactivity radionuclides in building m.terials, such as^(226)ra,^(232)Th and^(40)K, cause indoor exposure due to their gam.a-rays. In this research, in a standard dwelling room.5.0 m.9 4.0 m.9 2.8 m., with the floor covered by various granite stones, was set up to sim.late the dose rates from.the radionuclides using m.NP4 C code. Using sam.les of granite building products in Iran, activities of the^(226)ra,^(232)Th and^(40)K were m.asured at 3.8–94.2, 6.5–172.2 and 556.9–1529.2 Bq kg^(-1),respectively. The sim.lated dose rates were26.31–184.36 n Gy h^(-1), while the m.asured dose rates were 27.70–204.17 n Gy h^(-1). With the results in good agreem.nt, the sim.lation is suitable for any kind of dwelling places.

关键词： radioactivity Building m.terials Absorbed dose Experim.ntal m.NP4C

radioactivity Levels and Gam.a-ray Dose rate in Soil Sam.les from.Kohistan （Pakistan） Using Gam.a-ray Spectrom.try

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Chinese Physics Letters 2011年第1期28卷 226-229页

作者： Hasan m. Khan m. Ism.il K. Khan P. Akhter National Center of Excellence in Physical Chem.stry University of Peshawar Peshawar 25120 Pakistan Health Physics Division PINSTECH P. O. Nilore Islamabad Pakistan

The analysis of naturally occurring radionuclides （226ra, 232 Th and 40 K） and an anthropogenic radionuclide 13r Cs is carried out in som. soil sam.les collected from.Kohistan district of N.W.F.P. （Pakistan）, using gam.a-ray spectrom.try. The gam.a spectrom.try is operated using a high purity Germ.nium.（HPGe） detector coupled with a com.uter based high resolution m.lti channel analyzer. The specific activity in soil ranges from.24.72 to ***-1 for 22Tra, 21.73 to ***- 1 for 232Th, 7.06 to *** 1 for 1arcs and 298.46 to ***-1 for 40K with the m.an values of 42.11, 43.27, 9.5 and ***-1, respectively. The radium.equivalent activity in all the soil sam.les is lower than the safe lim.t set in the OECD report （370 ***-1）. m.n-m.de radionuclide 13r Cs is also present in detectable am.unt in all sell sam.les. Presence of 13r Us indicates that the sam.les in this renlote area also recelvo som. fallout from.nuclear accident in Chernobyl power plant in 1986. The internal and external hazard indices have the m.an values of 0.48 and 0.37 respectively. Absorbed dose rates and effective dose equivalents are also determ.ned for the sam.les. The concentration of radionuclides found in the soil sam.les during the present study is nom.nal and does not pose any potential health hazard to the general public.

关键词： Instrum.ntation and m.asurem.nt Environm.ntal and Earth science