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Phase Evolution during the Sintering of Submicron Ti(C,n)-Based Cermets

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Rare Metals 2001年第4期20卷 248-254页

作者： Li, ch Xiong, WH Yu, LX Huazhong Univ Sci & Technol State Key Lab Plast Forming Simulat & Die & Mould Wuhan 430074 Peoples R China

The submicron powder mixtures of TiC-Tin-WC-Mo-C-ni sintered at 1400degreesC or below in vacuum were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. The results showed that Mo2C formed at 800degreesC or below. Both WC and Mo2C disappeared at 1200degreesC, and Tin disappeared at 1250degreesC. In addition, the variations of lattice constants of the titanium carbonitride and nickel binder phase with sintering temperature were experimentally obtained, and the reason was analyzed.

关键词： submicron cermet phase sintering

Impacts of PI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

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neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón Pérez-núñez María Fernanda González Ana María Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune *** phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mech.nisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and notch/PI3K/AKT *** targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)

Astrocytes, reactive astrogliosis, and glial scar formation in traumatic brain injury

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neural Regeneration Research 2025年第4期20卷 973-989页

作者： María Belén Cieri Alberto Javier Ramos Laboratorio de neuropatología Molecular IBCN UBA-CONICETFacultad de MedicinaUniversidad de Buenos AiresBuenos AiresArgentina

Traumatic brain injury is a global health crisis,causing significant death and disability *** that follows traumatic brain injury has serious consequences for neuronal survival and cognitive impairments,with astrocytes involved in this *** traumatic brain injury,astrocytes rapidly become reactive,and astrogliosis propagates from the injury core to distant brain *** astroglial proteins are downregulated near the traumatic brain injury core,while pro-inflammatory astroglial genes are *** altered gene expression is considered a pathological remodeling of astrocytes that produces serious consequences for neuronal survival and cognitive *** addition,glial scar formed by reactive astrocytes is initially necessary to limit immune cell infiltration,but in the long term impedes axonal reconnection and functional *** therapeutic strategies for traumatic brain injury are focused on preventing acute ***,cannabinoids,progesterone,beta-blockers,and cerebrolysin demonstrate neuroprotective benefits but most of them have not been studied in the context of *** this review,we discuss the cell signaling pathways activated in reactive astrocytes following traumatic brain injury and we discuss some of the potential new strategies aimed to modulate astroglial responses in traumatic brain injury,especially using cell-targeted strategies with miRnAs or lncRnA,viral vectors,and repurposed drugs.

关键词： astrocyte glial scar innate immunity neuroinflammation stab injury Toll-like receptors

Sex differences in aging and injured brain

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neural Regeneration Research 2025年第10期20卷 2901-2902页

作者： Jordan n.Williamson Yuan Yang University of Illinois Urbana-champaign Grainger College of EngineeringDepartment of BioengineeringUrbanaILUSA Carle Foundation Hospital Stephenson Family Clinical Research InstituteClinical Imaging Research CenterUrbanaILUSA University of Illinois Urbana-champaign Beckman Institute for Advanced Science and TechnologyUrbanaILUSA northwestern University Department of Physical Therapy and Human Movement SciencesChicagoILUSA

Background:The prevalence,age of onset,and symptomatology of traumatic brain injury,stroke,and neurodegenerative diseases(such as Alzheimer’s disease(AD),Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease)differ substantially between males and *** higher prevalence of these brain disorders has been attributed to females having a greater longevity compared with *** one of the greatest risk factors of acquired brain injury(such as stroke,traumatic brain injury caused by fall)and neurodegenerative disease is age.

关键词： Huntington prevalence traumatic

Self-assembled structures of a semi-rigid polyanion in aqueous solutions and hydrogels

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Science ch.na chemistry 2012年第5期55卷 735-742页

作者： SUn TaoLin WU ziliang GOnG JianPing Division of Biological Sciences Graduate School of Science Hokkaido University Sapporo 060-0810 Japan Faculty of Advanced Life Science Graduate School of Science Hokkaido University Sapporo 060-0810 Japan

Poly(2,2'-disulfonyl-4,4'-benzidine terephthalamide) (PBDT), a kind of liquid-crystalline (LC) molecule, has high molecular weight, negative charge and a semi-rigid structure. The aqueous solution of PBDT shows nematic liquid crystalline state above a critical PBDT concentration, CLC*, of 2 wt%-3wt%. Different from the flexible polyelectrolyte, PBDT shows a variety of self-assembling structures in aqueous solution with and without salt due to the semi-rigid nature and highly charged property. In addition, the hydrogels with ordered structure are developed by polymerizing a cationic monomer n-[3-(n,n-dimethylamino) propyl] acrylamide methyl chloride quarternary (DMAPAA-Q) in the presence of a small amount of PBDT below the CLC*. During the polymerization of cationic monomer, the polycations form a complex with semi-rigid PBDT through electrostatic interaction; these complexes self-assemble into ordered structures that are frozen in the hydrogel. Several different structures, including the anisotropic, dual network-like structure, and cylindrically symmetric structure, with various length scales from micrometer to millimeter, are observed. The hydrogels with ordered liquid crystalline assemblies and particular optical properties should promise applications in many fields, such as in bionics, tissue engineering, and mech.no-optical sensors.

关键词： hydrogels self-assembl polyelectrolyte semi-rigid polyion complex

Estimating rock properties using sound signal dominant frequencies during diamond core drilling operations

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Journal of Rock Mech.nics and Geotechnical Engineering 2019年第4期11卷 850-859页

作者： ch.Vijaya Kumar Harsha Vardhan ch.S.n.Murthy n.C.Karmakar Department of Mining Engineering National Institute of Technology KarnatakaSurathkalIndia Indian Institute of Technology (BHU) VaranasiIndia

In many engineering applications such as mining,geotechnical and petroleum industries,drilling operation is widely *** drilling operation produces sound by-product,which could be helpful for preliminary estimation of the rock ***,determination of rock properties is very difficult by the conventional methods in terms of high accuracy,and thus it is expensive and *** this context,a new technique was developed based on the estimation of rock properties using dominant frequencies from sound pressure level generated during diamond core drilling ***,sound pressure level was recorded and sound signals of these sound frequencies were analyzed using fast Fourier transform (FFT).Rock drilling experiments were performed on five different types of rock samples using computer numerical control (CnC) drilling mach.ne BMV 45 *** simple linear regression analysis,mathematical equations were developed for various rock properties,*** compressive strength,Brazilian tensile strength,density,and dominant frequencies of sound pressure *** developed models can be utilized at early stage of design to predict rock properties.

关键词： Rock properties Sound pressure level Fast Fourier transform (FFT) Sound signal Core drilling Dominant frequencies

Making bridges between preclinical and clinical insights into age-related cognitive decline

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neural Regeneration Research 2025年第8期20卷 2321-2322页

作者： David VC Brito Clévio nóbrega Algarve Biomedical Center-Research Institute(ABC-RI) Campus GambelasFaroPortugal Algarve Biomedical Center-(ABC) Campus GambelasFaroPortugal Faculty of Medicine and Biomedical Sciences(FMCB) University of AlgarveGambelas CampusFaroPortugal

With people living longer,the societal impact of age-related cognitive decline is becoming more pronounced(Crimmins,2015).Thus,it is increasingly important to comprehend the cognitive shifts linked to aging-whether th... 详细信息

关键词： bridges becoming insight

Amyloid-beta pathology-induced nanoscale synaptic disruption:the case of the GABA_B-GIRK assembly

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neural Regeneration Research 2025年第5期20卷 1409-1410页

作者： Rafael Lujan Alejandro Martín-Belmonte Sergi Ferré Francisco Ciruela Synaptic Structure Laboratory Instituto de Biomedicina de la UCLM(IB-UCLM)Departamento de Ciencias MédicasInstituto de Investigación en Salud de Castilla-La Mancha(IDISCAM)Facultad de MedicinaUniversidad Castilla-La ManchaCampus BiosanitarioC/AlmansaAlbaceteSpain Integrative neurobiology Section National Institute on Drug AbuseIntramural Research ProgramNational Institutes of HealthBaltimoreMDUSA Pharmacology Unit Department of Pathology and Experimental TherapeuticsSchool of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaNeuropharmacology&Pain GroupNeuroscience ProgramBellvitge Institute for Biomedical ResearchL’Hospitalet de LlobregatSpain

Alzheimer's disease (AD) is characterized by an imbalance between excitatory and inhibitory brain networks,leading to aberrant homeostatic synaptic *** has progressively been recognized as syna ptopathy and syna ptic dysfunction has been identified as a key component of its pathogenesis (Schirinzi et al.,2020).Syna ptic dysfunction is believed to precede synapse loss,a primary biological correlate of cognitive decline in AD,inevita bly associated with neuronal death.

关键词： Alzheimer pathology

Can a dam type of an alpine lake be derived from lake geometry?A negative result

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Journal of Mountain Science 2021年第3期18卷 614-621页

作者： Adam EMMER Vojtěch CURIn University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria Czech Academy of Sciences Prague 16500Czechia Global ch.nge Research Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies have been published *** studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by ***,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mech.nism(dam overtopping/dam breach)and thus GLOF *** this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam *** dataset of 851 lakes of the Cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the *** only promising results are obtained for extreme values(selected bins)of the *** instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed ***,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra.

关键词： Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed negative result Cordillera Blanca