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幼龄桃树对地被布局的生长反应

国外农学（果树） 1992年第2期 7-8页

作者： W.V.Welker d.m.glenn 杨槐俊

杂草及草地的竞争会严重削弱幼龄桃树的生长;除草剂可有效地控制定植桃树的地被物;幼龄桃树的营养和生长受地被面积大小的影响。本研究的目的在于评估地被布局对幼龄桃树生长的影响。

关键词：桃树幼树地被布局生长

Shock effects on the upper limit of the collision weld process window

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Advances in manufacturing 2024年第2期12卷 365-378页

作者： Blake Barnett Anupam Vivek glenn daehn department of materials Science and Engineering The Ohio State UniversityColumbusOH43210USA Army Research directorate Army Research LaboratoryDEVCOMAberdeen Proving GroundHarfordMD21005USA

The maximum flyer impact velocity based on a dynamic solidification cracking mechanism is proposed to describe the upper limit of collision welding process ***,the upper limit of the weld window is governed by the evolution of dynamic stresses and temperatures at the weld *** formulations for the upper limit of the collision weld window assume that both the flyer and target are made of the same material and approximate stress propagation velocities using the acoustic velocity or the shear wave velocity of the weld ***,collision welding fundamentally depends on the impacts that generate shockwaves in weld members,which can dominate the stress propagation velocities in thin weld ***,this study proposes an alternative weld window upper limit that approximates stress propagation using shock velocities calculated from modified 1-d Rankine-Hugoniot *** shock upper limit is validated against the experimental and simulation data in the collision welding literature,and offers a design tool to rapidly predict more accurate optimal collision weld process limits for similar and dissimilar weld couples compared to existing models without the cost or complexity of high-fidelity simulations.

关键词： Collision welding Solid-state welding Shock impact Weld process modelling Explosive bonding Laser impulse welding(LIW)

Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： m.d.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction model is applicable for analyses of Z-scan measurements with dAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data and the proposed theoretical models.

关键词： nonlinear phase media

Advances in teleophthalmology and artificial intelligence for diabetic retinopathy screening:a narrative review

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Annals of Eye Science 2024年第2期9卷 24-37页

作者： Tanvi Chokshi maria Jessica Cruz Jonathon Ross glenn Yiu Tschannen Eye Institute Department of OphthalmologyUniversity of CaliforniaDavis HealthSacramentoCAUSA department of Research College of MedicineCalifornia Northstate UniversityElk GroveCAUSA

Background and Objective:Advances in teleophthalmology and artificial intelligence(AI)for diabetic retinal screening is of growing public health ***,only 30–40%of patients with diabetes adhere to recommended diabetes screening *** enhance early detection and reduce vision threatening complications,there has been a growing number of teleophthalmology programs and novel AI algorithms with the aim to improve eye care *** purpose of this review is to assess current literature on teleophthalmology and AI for use in diabetic retinopathy(dR)screening,and to discuss advances and barriers to these innovative ***:Literature review involving teleophthalmology and AI for dR screening,with focus on the past *** Content and Findings:Teleophthalmology has demonstrated the ability to increase dR screening rates,enable earlier eye care access,and reduce healthcare *** AI-based dR screening programs appear accurate and effective,but detection of other ocular pathologies is still under development and not yet approved in the United ***,technological,financial,and legal barriers limit widespread adoption and long-term sustainability of teleophthalmology ***:The use of teleophthalmology and AI algorithms expands eye care access and helps prevent vision loss from dR and potentially other sight threatening *** in the process utilized for arriving at a particular diagnosis or decision to refer,often referred to as the“black box”,remains a multifaceted issue within the field of telemedicine for developing trust and improving patient-centered outcomes.

关键词： Teleophthalmology artificial intelligence(AI) diabetic retinopathy(dR) screening public health

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

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

Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural Regeneration Research 2025年第3期20卷 803-804页

作者： glenn A.Harris Lauren R.Hirschfeld Rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(mAPT) and can be classified as either 3-repeat(3R) or 4-repeat(4R) based on the number of repeat domains from alternative splicing of exon 10 of the mAPT gene.

关键词： tau metabolism diseases

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.molloy 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