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Journal of Forestry Research 2024年第5期35卷 26-36页

作者： Andrés Baietto Andrés Hirigoyen Jorge Hernández Amabelia del Pino Forest department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay National Research Program of Forest Production National Agriculture Research InstituteINIA97000 TacuarembóUruguay soil and Water department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay

Native grasslands in the Pampas of south America are increasingly being replaced by Eucalyptus and Pinus *** short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient *** model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic *** temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by ***;seasonal accumulated precipitation and mean maximum temperature affected litterfall by *** regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for ***(N=33;MAE(mean absolute error)=0.65;RMsE(root mean square error)=0.91;R^(2)=0.71)and ***(N=108;MAE=1.50;RMsE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(***:Ca>N>K>Mg>P;***:N>Ca>K>Mg>P)and micronutrients(*** and ***:Mn>Fe>Zn>Cu)in both *** study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems.

关键词： Afforestation Litterfall Nutrient recycling Climate modeling Myrtaceae Pinaceae

Therapeutic advances in neural regeneration for Huntington’s disease

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Neural Regeneration Research 2024年第9期19卷 1991-1997页

作者： Francesco d’Egidio Vanessa Castelli Giorgia Lombardozzi Fabrizio Ammannito Annamaria Cimini Michele d’Angelo department of Life Health and Environmental SciencesUniversity of L’AquilaL’AquilaItaly

Huntington’s disease is a neurodegenerative disease caused by the expansion mutation of a cytosine-adenine-guanine triplet in the exon 1 of the HTT gene which is responsible for the production of the huntingtin (Htt) protein. In physiological conditions, Htt is involved in many cellular processes such as cell signaling, transcriptional regulation, energy metabolism regulation, dNA maintenance, axonal trafficking, and antiapoptotic activity. When the genetic alteration is present, the production of a mutant version of Htt (mHtt) occurs, which is characterized by a plethora of pathogenic activities that, finally, lead to cell death. Among all the cells in which mHtt exerts its dangerous activity, the GABAergic Medium spiny Neurons seem to be the most affected by the mHtt-induced excitotoxicity both in the cortex and in the striatum. However, as the neurodegeneration proceeds ahead the neuronal loss grows also in other brain areas such as the cerebellum, hypothalamus, thalamus, subthalamic nucleus, globus pallidus, and substantia nigra, determining the variety of symptoms that characterize Huntington’s disease. From a clinical point of view, Huntington’s disease is characterized by a wide spectrum of symptoms spanning from motor impairment to cognitive disorders and dementia. Huntington’s disease shows a prevalence of around 3.92 cases every 100,000 worldwide and an incidence of 0.48 new cases every 100,000/year. To date, there is no available cure for Huntington’s disease. several treatments have been developed so far, aiming to reduce the severity of one or more symptoms to slow down the inexorable decline caused by the disease. In this context, the search for reliable strategies to target the different aspects of Huntington’s disease become of the utmost interest. In recent years, a variety of studies demonstrated the detrimental role of neuronal loss in Huntington’s disease condition highlighting how the replacement of lost cells would be a reasonable strategy to o

关键词： cell therapy exosomes extracellular vesicles Huntingtin Huntington’s disease medium spiny neurons neurodegenerative disease neurogenesis neuronal loss stem cells

Cross-method Analysis of Corotation Radii data set for spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 95-110页

作者： V.s.Kostiuk A.A.Marchuk A.s.Gusev sternberg Astronomical Institute Lomonosov Moscow State UniversityUniversitetsky pr.13119234 MoscowRussia Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1196140 St.PetersburgRussia saint Petersburg state University Universitetsky pr.28198504 St.PetersburgRussia

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its *** the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two *** initial analysis reveals that most objects have rather inconsistent corotation radius ***,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of *** findings do not have any relation to spiral type,Hubble classification,or presence of a *** other reasons,obtained results could be explained by the transient nature of spirals in a considerable part of *** have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies structure

Microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in Manufacturing 2024年第2期12卷 207-226页

作者： sana Zaki Nan Zhang Michael d.Gilchrist school of Mechanical and Materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2d computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： Micro feature shaping and electropolishing Micro mould tools Green electrolyte demoulding micro patterns

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková s.Šašek J.dittrich M.Knapek F.Lukáˇc d.Koutný J.Jaroš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(sPs)and selective laser melting(sLM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the sLM material and unmeasurably low porosity in the sPs *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the sLM and sPs materials,*** corrosion resistance of the sPs material in 0.1 M NaCl solution was superior to the sLM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the sLM *** the other hand,one of the primary outcomes of this study is that the sPs consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

Kinetics of glyphosate and aminomethylphosphonic acid sorption onto montmorillonite clays in soil and their translocation to genetically modified corn

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Journal of Environmental sciences 2024年第1期135卷 669-680页

作者： Meichen Wang Kelly J Rivenbark Timothy d Phillips Veterinary Physiology and Pharmacology College of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityTX 77845USA

The co-occurrence of glyphosate(GLP)and aminomethylphosphonic acid(AMPA)in contaminated water,soil,sediment and plants is a cause for concern due to potential threats to the ecosystem and human health.A major route of exposure is through contact with contaminated soil and consumption of crops containing GLP and AMPA ***,clay-based sorption strategies for mixtures of GLP and AMPA in soil,plants and garden produce have been very *** this study,in vitro soil and in vivo genetically modified corn models were used to establish the proof of concept that the inclusion of clay sorbents in contaminated soils will reduce the bioavailability of GLP and AMPA in soils and their adverse effects on plant *** of chemical concentration(1–10 mg/kg),sorbent dose(0.5%-3%in soil and 0.5%-1%in plants)and duration(up to 28 days)on sorption kinetics were *** time course results showed a continuous GLP degradation to *** inclusion of calcium montmorillonite(CM)and acid processed montmorillonite(APM)clays at all doses significantly and consistently reduced the bioavailability of both chemicals from soils to plant roots and leaves in a dose-and time-dependent manner without detectable *** treated with 0.5%and 1%APM inclusion showed the highest growth rate(p≤0.05)and lowest chemical bioavailability with up to 76%reduction in roots and57%reduction in *** indicated that montmorillonite clays could be added as soil supplements to reduce hazardous mixtures of GLP and AMPA in soils and plants.

关键词： Glyphosate AMPA Adsorption soil remediation Plant Hydroponic system

Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 891-910页

作者： N.d.NGUYEN T.N.NGUYEN Faculty of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City 71309Viet Nam Faculty of Engineering and Technology Kien Giang UniversityChau Thanh 92000Viet Nam

This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam *** analyses include three models for porosity distribution and two scenarios for thermal *** material properties are assessed under two conditions,i.e.,temperature dependence and temperature *** theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order *** governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev *** simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam *** findings highlight the significant influence of temperature-dependent(Td)material properties on metal foam beams'buckling and vibration responses.

关键词： Ritz method Chebyshev function buckling vibration metal foam beam higher-order beam theory(HOBT)

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert P.Hesselbach M.schorner V.Bagnoud R.Belikov P.drechsel B.Heuser O.sHumphries P.Katrik B.Lindqvist C.Qu R.Redmer d.Riley G.schaumann s.schumacher A.Tauschwitz d.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.Major P.Neumayer d.Kraus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GsI Helmholtzzentrum fur schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany European XFEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany state Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 K,in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure

Vanillylacetone attenuates cadmium chloride-induced hippocampal damage and memory loss through upregulation of nuclear factor erythroid 2-related factor 2 gene and protein expression

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Neural Regeneration Research 2024年第12期19卷 2750-2759页

作者： Fahaid H.A.L-Hashem salah O.Bashir Amal F.dawood Moutasem s.Aboonq Ismaeel Bin-Jaliah Abdulaiziz M.Al-Garni Mohamed d.Morsy department of Physiology College of MedicineKing Khalid UniversityAbhaSaudi Arabia department of Basic Medical sciences College of MedicinePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia department of Physiology College of MedicineTaibah UniversityAl-Madinah Al-MunawwarahSaudi Arabia department of Medicine College of MedicineKing Khalid UniversityAbhaSaudi Arabia

Memory loss and dementia are major public health concerns with a substantial economic *** stress has been shown to play a crucial role in the pathophysiology of hippocampal damage-induced memory *** investigate whether the antioxidant and anti-inflammatory compound vanillyla cetone(zingerone) can protect against hippocampal damage and memory loss induced by cadmium chloride(CdCl_(2)) administration in rats,we explo red the potential involvement of the nuclear factor erythroid 2-related factor 2(Nrf2) signaling pathway,which is known to modulate oxidative stress and *** healt hy male Wistar rats were divided into five groups:vehicle-treated(control),vanillylacetone,CdCl_(2),vanillylacetone+ CdCl_(2),vanillylacetone+ CdCl_(2)+ brusatol(a selective pharmacological N rf2inhibitor) *** effectively attenuated CdCl_(2)-induced damage in the dental gyrus of the hippocampus and improved the memory function assessed by the Morris Water Maze ***,vanillylacetone markedly decreased the hippocampal tissue levels of inflammatory biomarkers(interleukin-6,tumor necrosis factor-α,intracellular cell adhesive molecules) and apoptosis biomarkers(Bax and cleaved caspase-3).The control and CdCl_(2)-treated groups treated with va nillylacetone showed reduced generation of reactive oxygen species,decreased malondialdehyde levels,and increased superoxide dismutase and glutathione activities,along with significant elevation of nuclear Nrf2 mRNA and protein expression in hippocampal *** the protective effects of vanillylacetone we re substantially blocked by the co-administration of brusatol(a selective N rf2 inhibitor).Va nillylacetone mitigated hippocampal damage and memory loss induced by CdCl_(2),at least in part, by activating the nuclear transcription factor ***,vanillylacetone exerted its potent antioxidant and antiinflammatory actions.

关键词： hippocampus neuroprotective Nrf2 gene oxidative stress vanillylacetone

dynamic and electrical responses of a curved sandwich beam with glass reinforced laminate layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： N.sHAHVEIsI s.FELI department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsdT)and Frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(FE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory