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Heterogeneity of mature oligodendrocytes in the central nervous system

Neural Regeneration Research 2025年第5期20卷 1336-1349页

作者： chao Weng Adam M.R.groh Moein Yaqubi Qiao-Ling cui Jo Anne Stratton g.R.Wayne Moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

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Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

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Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin g.Willson Lauren e.cox Justin L.Hart Daniel c.Dey Department of geography University of AlabamaTuscaloosaAL 35487USA Department of environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an eF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba L.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,pcated that understory light penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

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Tempering Behavior of M50 Steel with Different Austenite Proportion Induced by High current Pulsed electron Beam

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稀有金属材料与工程 2012年第S1期41卷 475-477页

作者： g.e.Ozure Institute of High current electronics 4Academichesky Av.Tomsk 634055Russia

M50 steel was irradiated by high current pulsed electron beam(HcPeB)with different *** subsequent tempering was carried out between 500 and 625℃.Microstructure evolution was analyzed by scanning electron microscopy and X-ray *** is found that the HcPeB treatment could constrain martainsite transformation in the surface layer of the *** behavior of HcPeB remelted layer strongly depends on the proportion of retained *** saturated more carbon and metallic elements depict higher tempering *** tempered process,carbides precipitates among the grain and phase *** decreased solution of the elements promotes the retained austenite into martensite.

关键词： electron beam irradiation M50 steel tempering microstructure

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enhancement of electric conductivity in Transparent glasse—ceramic Nanocomposites of Bi_2O_3—BaTiO_3 glasses

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Journal of Materials Science & Technology 2013年第12期29卷 1166-1176页

作者： A.A.Bahgat M.g.Moustafa e.e.Shaisha Department of Physics Faculty of ScienceAl-Azhar University

The frequency and temperature dependent electrical conductivity measurements for heat-treated binary glass system with composition of （lO0-x）Bi203-xBaTi03 （x = 20, 30, 40 and 50, in mol%） were carried out. The glass was prepared by melt quenching technique and their corresponding glass-ceramic nanocomposites were obtained by suitable heat treatment. Nanostructured behavior and electrical properties of these glasses and their corresponding glass-ceramic nanocomposites were studied. X-ray diffraction （XRD） and differential scanning calorimetry confirmed the amorphous nature of the glasses. Moreover, XRD patterns of the samples indicate nanocrystallites embedded in the glass matrix. The Fourier transform infrared spectroscopy （FT-IR） spectral analysis showed that the band positions of glass system are within the wave number range of Bi06, Bi03 and Ti06 structural units. It is observed that the electrical conductivity is enhanced by 102-103 times in the transparent glass-ceramic nanocomposite phase. With further heat treatment, the conductivity decreased considerably in the stage of glass-ceramic nanocomposite phase as compared with the glassy phase sample. Therefore, partially devitrified phase is more suitable as cathode material in secondary batteries compared to its vitreous or fully crystalline counterpart. The conduction mechanism was confirmed to obey the adiabatic small polaron hopping （SPH）. Ac conductivity measurements were performed as a function of temperature and frequency, showing a very slow increasing rate at low temperatures and then a fast rate at higher temperatures.

关键词： Barium titanat Transparent glass--ceramic nanocomposites Dc electrical conductivity Ac electrical conductivity Smallpolaron hopping

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effect of cobalt substitution on structure and magnetic properties of Nd0.4Zr0.6Fe10-xcoxSi2（x =0-3） alloys and their ribbons

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Journal of Rare earths 2019年第10期37卷 1096-1101页

作者： M.gjoka c.Sarafidis g.giannopoulos D.Niarchos g.Hadjipanayis J.A.Tabares g.A.Pérez Alcázar L.e.Zamora Institute of Nanoscience and Nanotechnology NCSR Demokritos15310AthensGreece Department of Physics and Astronomy University of DelawareNewarkDEUSA Department of Physics Aristotle University of Thessaloniki54124ThessalonikiGreece Departamento de Física Universidad del ValleA.A.25360CaliColombia

This study reports the stabilization of the RFe12-type based compounds where part of R and Fe are substituted with Zr and co and Si, respectively, in order to examine whether these rare-earth-lean materials are suitable for applications as permanent magnets. Structural and magnetic characterization of the family of alloys with the general formula Nd0.4 Zr0.6 Fe10-xcoxSi2(x = 0 -3) and their melt-spun ribbons were carried out using X-ray diffraction and M€ossbauer spectroscopy. The ThMn12-type structure is obtained for all samples as the majority phase with a minority a-Fe(coSi) phase(less than 5 wt%) as it was estimated by XRD for x = 1 and 2. The curie temperature increases linearly with co substitution from 561 K for x = 0 to 712 K for x = 3. The saturation magnetization decreases slightly from 130.5(x =1)to 129.1 A·m2/kg(x=3), while the anisotropy field is following the same trend.

关键词： Permanent magnets X-ray diffraction M€ossbauer spectroscopy Rare-earth-lean magnetic materials Magnetic properties Melt-spun ribbons

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Associations between aerobic and muscle-strengthening physical activity,sleep duration,and risk of all-cause mortality:A prospective cohort study of 282,473 ***

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Journal of Sport and Health Science 2023年第1期12卷 65-72页

作者： Mitch J.Duncan Stina Oftedal christopher e Kline Ronald c.Plotnikoff elizabeth g.Holliday School of Medicine&Public Health College of HealthMedicineand WellbeingThe University of NewcastleCallaghanNSW 2308Australia Priority Research centre for Physical Activity and Nutrition The University of NewcastleCallaghanNSW 2308Australia Department of Health&Human Development The University of PittsburghPittsburghPA 15261USA School of education University of NewcastleCallaghanNSW 2308Australia

Purpose:To examine the joint associations between meeting guidelines for physical activity(PA)and sleep duration and all-cause mortality risk among ***:Participants were adults(n=282,473)aged 18-84 years who participated in the 2004-2014 *** Health Interview *** status was ascertained using the National Death Index through December ***-reported PA(Active:meeting both aerobic(AeR)and muscle-strengthening(MSA)guidelines,AeR only(AeR),MSA only(MSA),or not meeting either AeR or MSA(Inactive))and sleep duration(Short,recommended(Rec),or Long)were classified according to guidelines,and 12 PA-sleep categories were *** hazard ratios and 95%confidence intervals(95%cIs)for all-cause mortality risk were estimated using cox proportional hazards regression ***:A total of 282,473 participants(55%females)were included;18,793 deaths(6.7%)occurred over an average follow-up of 5.4 *** to the Active-Rec group,all other PA-sleep groups were associated with increased mortality risk except for the Active-Short group(hazard ratio=1.08;95%cI:0.92-1.26).The combination of long sleep with either MSA or Inactive appeared to be *** a given sleep duration,mortality risk progressively increased among participants classified as AeR,MSA,and *** each activity level,the mortality risk was greatest among adults with long ***:Relative to adults meeting guidelines for both PA and sleep duration,adults who failed to meet guidelines for both AeR and muscle strengthening PA and who also failed to meet sleep duration guidelines had elevated all-cause mortality *** results support interventions targeting both PA and sleep duration to reduce mortality risk.

关键词： Activity-sleep patterns All-cause mortality Prospective Resistance training

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INFLUeNceS OF cASTINg SPeeD AND SeN DePTH ON FLUID FLOW IN THe FUNNeL TYPe MOLD OF A THIN SLAB cASTeR

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Acta Metallurgica Sinica(english Letters) 2007年第1期20卷 15-26页

作者： B.W. Li X.Y. Tian e.g. Wang J.c. He Key Laboratory of National education Ministry for electromagnetic Processing of Materials Northeastern University Shenyang 110004 China

In recent years, thin slab continuous casting technology has been widely used to improve the quality of the product and to reduce the cost. One of the challenges faced by this technology is to design reasonable flow patterns, which strongly affect the surface and inner properties of the final slab in the mold. With the fixed scales and complex geometrical structures of nozzle and funnel type mold, a series of numerical simulations are made to analyze the flow patterns in melt steel using finite volume method based on structured body fitted coordinate grids. The cFD （computational fluid dynamics） package is validated first using one typical case described in previously published studies, and then it is developed to study the effect of operational parameters on fluid flow in thin slab caster. Two operational parameters, casting speed and SeN （submerged entry nozzle） depth, are mainly considered for numerical analysis. On the basis of present simulations, the reasonable SeN submergence depths corresponding to different casting speeds are suggested according to fluid flow characteristics like, flow jet impingement on the narrow side of the mold, flow speed of the melt steel beneath the meniscus and the recirculation region. This is the first stage of study on the numerical analysis of the whole thin slab casting process with electromagnetic brake.

关键词： continuous casting thin slab submerged entry nozzle (SeN) numerical analysis funnel type mold standard k-ε model RNg (renormalization group) k-ε model

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emissions from the combustion of eucalypt and pine chips in a fluidized bed reactor

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Journal of environmental Sciences 2016年第4期28卷 246-258页

作者： e.D.Vicente L.A.c.Tarelho e.R.Teixeira M.Duarte T.Nunes c.colombi V.gianelle g.O.da Rocha A.Sanchez de la campa c.A.Alves centre for environmental and Marine Studies Department of Environment and PlanningUniversity of Aveiro Regional centre for Air Quality Monitoring Environmental Monitoring Sector ARPA Federal University of Bahia Chemical Institute40170-290Campus de Ondina centre for Research in Sustainable chemistry (cIQSO) Joint Research Unit to CSIC "Atmospheric Pollution"University of HuelvaCampus El Carmen

Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution,reduced costs and improved efficiency of *** the european Union（eU）energy directive,biomass is a suitable renewable *** aim of this study was to experimentally quantify and characterize the emission of particulate matter（PM（2.5））resulting from the combustion of two biomass fuels（chipped residual biomass from pine and eucalypt）,in a pilot-scale bubbling fluidized bed（BFB）combustor under distinct operating *** variables evaluated were the stoichiometry and,in the case of eucalypt,the leaching of the *** cO and PM（2.5）emission factors were lower when the stoichiometry used in the experiments was higher（0.33±0.1 g cO/kg and 16.8±1.0 mg PM（2.5）/kg,dry gases）.The treatment of the fuel by leaching before its combustion has shown to promote higher PM（2.5）emissions（55.2±2.5 mg/kg,as burned）.Organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass,while carbonate（cO3^（2-））accounted for between 2.3 and 8.5 wt.%.The particulate mass was mainly composed of inorganic matter（71% to 86% of the PM（2.5）mass）.compared to residential stoves,BFB combustion generated very high mass fractions of inorganic *** was the water soluble ion in higher concentration in the PM（2.5）emitted by the combustion of eucalypt,while calcium was the dominant water soluble ion in the case of pine.

关键词： Biomass combustion Fluidized bed PM2.5emissions chemical composition

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Laparoscopic fenestration of multiple giant biliary mucinous cystadenomas of the liver

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World Journal of gastroenterology 2008年第26期14卷 4257-4259页

作者： A Manours e Lagoudianakis L Alevizos H Markogiannakis g Kafiri c Bramis K Filis K Toutouzas First Department of Propaedeutic Surgery Hippocrateion Hospital University of Athens Athens Medical School Athens 11527 Greece

Biliary cystadenomas of the liver are rare, cystic neoplasms of the biliary ductal system usually occur in middle aged women. We report a case of synchronous multiple huge biliary mucinous cystadenomas with unique features. This is, according to our knowledge, the first report in the literature about three synchronously occurring hepatobiliary cystadenomas. cystadenomas have a strong tendency to recur, particularly following incomplete excision, and a potential of malignant transformation. A therapeutic re-evaluation may be necessary when the diagnosis of hepatobiliary cystadenoma is made after the operation and an open liver resection should be considered.

关键词： Biliary cystadenoma Liver cysts Laparoscopic fenestration

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On the microstructural origin of premature failure of creep strength enhanced martensitic steels

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Journal of Materials Science & Technology 2021年第28期87卷 269-279页

作者： J.Li c.Xu g.Zheng W.J.Dai c.c.Bu g.chen MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology Engineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing210094China Nanjing Jiuzhu New Materials Institute co. Ltd.Nanjing211151China condensed Materials Laboratory co. Ltd.Yangzhou225200China Yangzhou chengde Steel Pipe co. Ltd.Yangzhou225200China

The creep strength enhanced martensitic steels are key material for the main power generating units in ultra-supercritical *** on the evaluation of their creep rupture life show there is an overestimation of rupture life after long-term creep,which is known as premature ***,the microstructural origin of the premature failure remains *** in this study,we have carefully investigated the microstructural transformations and their influences on creep rupture behavior,showing that the evolution of martensite and M_(23)c_(6) carbides as well as Laves phase are responsible for the premature *** using multi-step TTP-LMP method,we confirmed a three-stage creep rupture behavior under different stress *** quantitative analysis showed that the coarsening of M_(23)c_(6) carbides and recovery of martensite exert equal and dominant effects on the premature failure in the medium stress region,while precipitation and coarsening of Laves phase are responsible for the premature failure in the low stress region.

关键词： creep strength enhanced martensitic steel Premature failure M_(23)c_(6)carbides Martensite recovery Laves phase

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