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Highly toxic Aβ begets more Aβ

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Neural Regeneration Research 2024年第9期19卷 1871-1872页

作者： merc m.Kemeh Noel d.Lazo Gustaf H.Carlson School of Chemistry and Biochemistry Clark UniversityWorcesterMAUSA

Alzheimer’s disease(Ad)is the most common form of dementia-the 7th leading cause of death *** the tissue level,Ad is characterized by the presence of extracellular amyloid plaques that are comprised primarily of the amyloid-βpeptide(Aβ),and by intraneuronal neurofibrillary tangles composed of *** genetics of early-onset Ad and longitudinal brain-imaging studies of late-onset Ad indicate that extracellular Aβdeposition,in general,precedes neurofibrillary tangle formation in neurons(Hampel et al.,2021;Young-Pearse et al.,2023).

关键词： Aβ tau Alzheimer death

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： d A Baghdasaryan V A Harutynyan E m Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.d.Hossain m.S.Sikder m.N.I.Khan m.R.Rahman Physics discipline Khulna UniversityKhulna9208Bangladesh department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRd),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EdX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRd patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EdX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EdX Resistivity

Radioisotope production using lasers:From basic science to applications

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matter and Radiation at Extremes 2024年第3期9卷 31-44页

作者： m.R.d.Rodrigues A.Bonasera m.Scisciò J.A.Pérez-Hernández m.Ehret F.Filippi P.L.Andreoli m.Huault H.Larreur d.Singappuli d.m.lloy d.Raffestin m.Alonzo G.G.Rapisarda d.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.mcNamee m.La Cognata S.Palmerini T.Carriere m.Cipriani G.di Giorgio G.Cristofari R.de Angelis G.A.P.Cirrone d.margarone L.Giuffrida d.Batani P.Nicolai K.Batani R.Lera L.Volpe d.Giulietti S.Agarwal m.Krupka S.Singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia School of mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom dipartimento di Fisica e Astronomia“E.majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly ELI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of meV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Charting the course to solid-state dual-ion batteries

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Carbon Energy 2024年第3期6卷 132-177页

作者： Habtom d.Asfaw Antonia Kotronia Nuria Garcia-Araez Kristina Edström daniel Brandell department of Chemistry Ångström LaboratoryUppsala UniversityUppsalaSweden department of Chemistry University of SouthamptonSouthamptonUK

An electrolyte destined for use in a dual-ion battery(dIB)must be stable at the inherently high potential required for anion intercalation in the graphite electrode,while also protecting the Al current collector from anodic dissolution.A higher salt concentration is needed in the electrolyte,in comparison to typical battery electrolytes,to maximize energy density,while ensuring acceptable ionic conductivity and operational *** recent years,studies have demonstrated that highly concentrated organic electrolytes,ionic liquids,gel polymer electrolytes(GPEs),ionogels,and water-in-salt electrolytes can potentially be used in *** can help reduce the use of solvents and thus lead to a substantial change in the Coulombic efficiency,energy density,and long-term cycle life of ***,GPEs are suited to manufacture compact dIB designs without separators by virtue of their mechanical strength and electrical *** this review,we highlight the latest advances in the application of different electrolytes in dIBs,with particular emphasis on GPEs.

关键词： anion intercalation concentrated electrolytes dual-ion battery graphite ionic liquids polymer electrolyte

Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang d.m.Gillies E.Spanswick E.F.donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SmILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez m.Gutiérrez-Roa C.Giménez-Rubio d.Ríos-Ruiz P.Arévalo-Cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro d.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRdE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 m KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRdE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

development and testing of a high-power S-band klystron at BINP SB RAS

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Nuclear Science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnyakov S.Samoylov d.Nikiforov V.Ivanov m.Arsentyeva d.Chekmenev O.Pavlov I.Pivovarov Budker Institute of Nuclear Physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk State University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the S-band high-power klystron,accomplished at the Budker Institute of Nuclear Physics,Siberian Branch,Russian Academy of Sciences(BINP SB RAS).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 mHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

Numerical Analysis of Permeability of Functionally Graded Scaffolds

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Fluid dynamics and materials Processing 2024年第7期20卷 1463-1479页

作者： Bratsun d. Elenskaya N. Siraev R. Tashkinov m. Laboratory of mechanics of Biocompatible materials and devices Perm National Research Polytechnic University Perm 614990 Russian Federation

In this work, we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion bioreactor. We consider two popular solid matrix designs based on triply periodic minimal surfaces, the Schwarz P (primitive) and d (diamond) surfaces, which enable the creation of materials with controlled porosity gradients. The latter property is crucial for regulating the shear stress field in the pores of the scaffold, which makes it possible to control the intensity of cell growth. The permeability of functionally graded materials is studied within the framework of both a microscopic approach based on the Navier-Stokes equation and an averaged description of the liquid filtration through a porous medium based on the equations of the darcy or Forchheimer models. We calculate the permeability coefficients for both types of solid matrices formed by Schwarz surfaces, study their properties concerning forward and reverse fluid flows, and determine the ranges of Reynolds number for which the description within the darcy or Forchheimer model is applicable. Finally, we obtain a shear stress field that varies along the sample, demonstrating the ability to tune spatially the rate of tissue growth. © This work is licensed under a Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

关键词： filtration models functionally graded materials Porous media scaffolds