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Grain refinement of mg-Ca alloys by native mgO particles

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Journal of magnesium and Alloys 2024年第3期12卷 980-996页

作者： Shihao Wang Yun Wang Quentin m.Ramasse Zhongyun Fan Super STEm Laboratory SciTech Daresbury CampusDaresbury WA44ADUK School of Chemical and Process Engineering University of LeedsLeeds LS29JTUK BCAST Brunel University LondonUxbridgeMiddlesex UB83PHUK

In mg-Ca alloys the grain refining mechanism,in particular regarding the role of nucleant substrates,remains the object of *** native mgO is being recognised as a nucleating substrate accounting for grain refinement of mg alloys,the possible interactions of mgO with alloying elements that may alter the nucleation potency have not been elucidated ***,we design casting experiments of mg-xCa alloys varied qualitatively in number density of native mgO,which are then comprehensively studied by advanced electron *** results show that grain refinement is enhanced as the particle number density of mgO *** native mgO particles are modified by interfacial layers due to the co-segregation of Ca and N solute atoms at the mgO/mg *** aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy,we reveal the nature of these Ca/N interfacial layers at the atomic *** of the crystallographic termination of mgO,Ca and N co-segregate at the mgO/mg interface and occupy mg and O sites,respectively,forming an interfacial structure of a few atomic *** interfacial structure is slightly expanded,less ordered and defective compared to the mgO matrix due to compositional deviations,whereby the mgO substrate is altered as a poorer template to nucleate mg *** solidification in a TP-1 mould,the impotent mgO particles account for the grain refining mechanism,where they are suggested to participate into nucleation and grain initiation processes in an explosive *** work not only reveals the atomic engineering of a substrate through interfacial segregation but also demonstrates the effectiveness of a strategy whereby native mgO particles can be harnessed for grain refinement in mg-Ca alloys.

关键词： mg-Ca alloy Grain refinement mgO Interfacial segregation STEm/EELS Solidification.

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

Neurovascular unit on a chip:the relevance and maturity as an advanced in vitro model

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Neural Regeneration Research 2024年第6期19卷 1165-1166页

作者： Sujey Palma-Florez Anna Lagunas mònica mir Nanobioengineering Group Institute for Bioengineering of Catalonia(IBEC)Barcelona Institute of Science and Technology(BIST)BarcelonaSpain CIBER-BBN ISCIIIMadridSpain Department of Electronics and Biomedical Engineering University of BarcelonaBarcelonaSpain

The brain is a high-energy demanding organ,consuming around 20%of the metabolic energy *** fulfill this demand,cerebral blood flow(CBF)supplies oxygen and glucose continuously through the intricate network of cerebral blood *** for many years brain activity and blood flow were conceived as independent processes,mRI-based functional brain imaging demonstrated that there is a coupling between them.

关键词： cerebral maturity consuming

The gold-telluride connection:Evidence for multiple fluid pulses in the Jinqingding telluride-rich gold deposit of Jiaodong Peninsula,Eastern China

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Geoscience Frontiers 2024年第3期15卷 146-165页

作者： Wenyan Cai mingchun Song m.Santosh Jian Li School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255049China Hebei Key Laboratory of Strategic Critical mineral Resources Hebei GEO UniversityShijiazhuang 050031China School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA 5005Australia

The mechanism of gold migration,enrichment,and precipitation in forming world-class gold deposits has been a topic of wide interest,particularly where these deposits are abundant in *** Jiaodong Peninsula in eastern China hosts some of the world-class gold deposits among which the Jinqingding deposit is one of the best examples with substantial telluride mineralization and thus provides opportunity to investigate the genetic connection between tellurium and gold *** orebody in this deposit is hosted in the NE-NNE-trending Jiangjunshi-Quhezhuang fault with the Jurassic Kunyushan granitic pluton as wall *** deposit involved three mineralization stages as inferred from assemblages and crosscutting relationships between *** stages are:(I)pre-ore gold-poor quartz-pyrite veins,(II)main ore auriferous quartz-pyrite-Te/Bi-minerals±sphalerite±chalcopyrite±barite±marcasite veins,and(III)post-ore quartz-calcite *** present here the textural,isotopic,and geochemical variations of different stages/generations of pyrite based on scanning electron microscopy-energy dispersive spectroscopy(SEm-EDS),electron probe microanalysis(EPmA),and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-mS).Pyrite in the Jinqingding deposit displays distinct ***1a shows a porous and dissolution-reprecipitation texture in the core,whereas Py1b exhibits a smooth and flat *** analysis reveals contrasting elemental compositions,with Py1a characterized by low Au(avg.0.14 ppm),As(avg.15.57 ppm),Ag(avg.17.71 ppm),and Te(avg.19.22 ppm)contents,but elevated Co(avg.1068.10 ppm)and Ni(224.12 ppm)concentrations,and variable sulfur isotopic composition(δ^(34)SV-CDT=9.54‰-12.12‰).Conversely,Py1b displays increased concentrations of these elements and a more concentratedδ^(34)SV-CDT value(11.99‰-12.23‰),possibly associated with weak coupled dissolution-reprecipitation(CDR)*** Stage II,pyrite can be further categorized

关键词： Episodic fluid pulses Sulfur reservoir Gold-Te precipitation Jinqingding deposit Jiaodong Peninsula

On thermoelastic problem based on four theories with the efficiency of the magnetic field and gravity

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Journal of Ocean Engineering and Science 2024年第4期9卷 338-347页

作者： A.A.Kilany A.N.Abd-alla A.m.Abd-Alla S.m.Abo-Dahab Department of mathematics Faculty of ScienceSohag UniversitySohag 82524 Egypt Department of Computer Science Faculty of Computers and InformationLuxor UniversityEgypt Department of mathematics Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The fundamental objective of this paper is to study the effectiveness of magnetic field and gravity on an isotropic homogeneous thermoelastic structure based on four theories of generalized *** another meaning,the models of coupled dynamic theory(CDT),Lord-Shulman(LS),Green-Lindsay(GL)as well as Green-Naghdi(GN II)will be taken in the ***,applying the harmonic method(normal mode technique),the solution of the governing equations and the expressions for the components of the displacement,temperature and(mechanical and maxwell’s)stresses is taken into account and calculated *** impacts of the gravity and magnetic field are illustrated graphically which are pronounced on the different physical ***,the results of some research that others have previously obtained may be found some or all of them as special cases from this study.

关键词： Generalized thermoelasticity Gravity magnetic field Green and Naghdi TheoryⅡ Normal mode approach

Hydroxytyrosol and Parkinson's disease:protective actions against alpha-synuclein toxicity

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Neural Regeneration Research 2024年第7期19卷 1427-1428页

作者： Ruth Hornedo-Ortega Ana m.Espinosa-Oliva Departamento de Nutrición y Bromatología Toxicología y Medicina LegalFacultad de FarmaciaUniversidad de SevillaSevilleSpain Instituto de Biomedicina de Sevilla IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de SevillaSevillaSpain Departamento de Bioquímica y Biología molecular Facultad de FarmaciaUniversidad de SevillaSevillaSpain

Parkinson’s disease:Parkinson’s disease(PD) is the second most prevalent neurodegenerative disease,after Alzheimer’s disease,affecting 1%of the general population over the age of *** to data from the World Health Organization(WHO),its prevalence has doubled in the past 25 *** 2019,global estimates indicated over 8.5 million individuals with PD and it is suggested that PD caused 329000 deaths,an increase of over 100% since 2000(WHO,2022).

关键词： protective Alzheimer prevalence

Clinical implications of reconsideration of enthesitis/enthesopathy/enthesial erosion,as tendon attachmentlocalized avulsions and stress fracture equivalents

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World Journal of Orthopedics 2024年第10期15卷 902-907页

作者： Bruce m Rothschild Department of medicine Indiana University Ball Memorial HospitalMuncieIN 47303United States

Recognizing the mechanical origin of enthesitis/enthesopathy and the avulsion-nature of what had previously been considered erosions,it seems inappropriate to attribute it to stresses related to a person’s normal ***,sudden or unconditioned repetitive stresses appears the more likely *** of enthesial reaction have lacked standardization as to findings present among individuals who appear to be *** evaluation by palpation and mani-pulation may be as effective as application of radiologic *** of the mechanical nature of the disease,including individuals with inflammatory arthritis suggests prescription of mechanical solutions that reduce stresses across the involved enthesis.

关键词： Enthesitis Epicondylitis Erosion Avulsion Clinical examination

Assessment of spongy moth infestation impacts on forest productivity and carbon loss using the Sentinel-2 satellite remote sensing and eddy covariance flux data

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Ecological Processes 2024年第2期13卷 231-245页

作者： Nur Hussain Alemu Gonsamo Shusen Wang m.Altaf Arain School of Earth Environment and Society and McMaster Centre for Climate Change Mc Master University Canada Centre for Remote Sensing Natural Resources Canada

Background Deciduous forests in eastern North America experienced a widespread and intense spongy moth（Lymantria dispar） infestation in 2021. This study quantified the impact of this spongy moth infestation on carbon（C） cycle in forests across the Great Lakes region in Canada, utilizing high-resolution（10 × 10 m2） Sentinel-2 satellite remote sensing images and eddy covariance（EC） flux data. Study results showed a significant reduction in leaf area index（LAI） and gross primary productivity（GPP） values in deciduous and mixed forests in the region in *** Remote sensing derived, growing season mean LAI values of deciduous（mixed） forests were 3.66（3.18）, 2.74（2.64）, and 3.53（2.94） m2m-2in 2020, 2021 and 2022, respectively, indicating about 24（14）% reduction in LAI, as compared to pre-and post-infestation years. Similarly, growing season GPP values in deciduous（mixed） forests were 1338（1208）, 868（932）, and 1367（1175） g C m-2, respectively in 2020, 2021 and 2022, showing about 35（22）% reduction in GPP in 2021 as compared to pre-and post-infestation years. This infestation induced reduction in GPP of deciduous and mixed forests, when upscaled to whole study area（178,000 km2）, resulted in 21.1（21.4） mt of C loss as compared to 2020（2022）, respectively. It shows the large scale of C losses caused by this infestation in Canadian Great Lakes *** The methods developed in this study offer valuable tools to assess and quantify natural disturbance impacts on the regional C balance of forest ecosystems by integrating field observations, high-resolution remote sensing data and models. Study results will also help in developing sustainable forest management practices to achieve net-zero C emission goals through nature-based climate change solutions.

关键词： Spongy moth Infestation Carbon Gross ecosystem productivity Leaf area index Temperate forest Remote sensing Sentinel-2 Eddy covariance

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