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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 worldwide.At 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 tau.molecular 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 proposed.The charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are calculated.The electron binding energies are calculated for different NPL thicknesses.It 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 account.Also,it is demonstrated that the binding energies are increasing with the number of impurities.We 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 gas.The 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)-xO_(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 devices.For the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important issues.This 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)-xO_(4) ferrites,where x=0.00,0.06,and 0.10.The 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 samples.The XRd patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped samples.The 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 concentration.The FTIR analysis also proves the spinel cubic phase of the samples.The average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 nm.VSm 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)-xO_(4) ferrites.Particularly,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 ferrites.The permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric losses.Frequency dependent resistivity and impedance analysis also show the improved nature.From 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

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 airglow.Because 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 emission.Under 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 aurora.In 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 data.We 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 model.We demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake stations.The RGB response is found to be nonlinear.Empirical 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 users.The 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

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 micrometers.Protons with energies of tens of meV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary targets.Under such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical application.The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators.In 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 applications.At 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 production.The experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,Spain.Angular distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium detector.Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[Nucl.Instrum.methods Phys.Res.,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 safety.In 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 dIBs.GPEs 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 dIBs.Furthermore,GPEs are suited to manufacture compact dIB designs without separators by virtue of their mechanical strength and electrical performance.In 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

Sarcopenic obesity in patients awaiting liver transplant: Unique challenges for nutritional recommendations

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World Journal of Transplantation 2024年第2期14卷 40-47页

作者： darya m Herscovici Katherine m Cooper Alessandro Colletta michelle Rightmyer Alexandra Shingina Lauren d Feld department of medicine UMass Chan Medical SchoolWorcesterMA 01655United States division of Transplant Nutrition UMass Chan Medical SchoolWorcesterMA 01655United States department of medicine Vanderbilt University Medical CenterNashvilleTN 37215United States division of Gastroenterology UMass Chan Medical SchoolWorcesterMA 01655United States

Sarcopenic obesity increases the risk of mortality in patients with liver disease awaiting liver transplantation and in the post-transplant period.Nutrition recommendations for individuals with sarcopenia differ from recommendations for patients with obesity or sarcopenic obesity.While these nutrition guidelines have been established in non-cirrhotic patients,established guidelines for liver transplant candidates with sarcopenic obesity are lacking.In this paper,we review existing literature on sarcopenic obesity in patients with chronic liver disease and address opportunities to improve nutritional counseling in patients awaiting liver transplantation.

关键词： Nutrition Sarcopenia Sarcopenic obesity Liver transplant Cirrhosis Chronic liver disease Body composition myostatin

Liquid biopsy for gastric cancer:Techniques,applications,and future directions

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World Journal of Gastroenterology 2024年第12期30卷 1680-1705页

作者： Cristina díaz del Arco m Jesús Fernández Aceñero Luis Ortega medina department of Surgical Pathology Health Research Institute of the Hospital Clínico San CarlosHospital Clínico San CarlosMadrid 28040Spain department of Legal medicine Psychiatry and PathologyUniversidad Complutense de MadridMadrid 28040Spain

After the study of circulating tumor cells in blood through liquid biopsy(LB),this technique has evolved to encompass the analysis of multiple materials originating from the tumor,such as nucleic acids,extracellular vesicles,tumor-educated platelets,and other metabolites.Additionally,research has extended to include the examination of samples other than blood or plasma,such as saliva,gastric juice,urine,or stool.LB techniques are diverse,intricate,and variable.They must be highly sensitive,and pre-analytical,patient,and tumor-related factors significantly influence the detection threshold,diagnostic method selection,and potential results.Consequently,the implementation of LB in clinical practice still faces several challenges.The potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases,monitoring treatment response,early identification of relapses,or assessing patient risk.On the other hand,gastric cancer(GC)is a disease often diagnosed at advanced stages.despite recent advances in molecular understanding,the currently available treatment options have not substantially improved the prognosis for many of these patients.The application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these patients.In this comprehensive review,from a pathologist’s perspective,we provide an overview of the main options available in LB,delve into the fundamental principles of the most studied techniques,explore the potential utility of LB application in the context of GC,and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

关键词： Liquid biopsy Gastric cancer Circulating tumor cells Cell-free dNA Circulating tumor dNA molecular

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 vs.RHE) 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