检索结果-南通市图书馆

Impacts of pI3K/protein kinase b pathway activation in reactive astrocytes: from detrimental effects to protective functions

在线全文

学校读者我要写书评

暂无评论

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 mechanisms 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)

perturbative Quantum Chromodynamics α_(s)^(4)-Order Corrections to the Ratio R for τ Decay

在线全文

学校读者我要写书评

暂无评论

Chinese physics Letters 1998年第10期15卷 711-712页

作者： b.p.Nigam Department of physics&Astronomy Box 871504Arizona State University TempeArizonaUSA 85287-1504

The perturbative quantum chromodynamics correction to the semihadronic decay rate R of the heavy leptonτwas expressed by braaten as an expansion in powers ofαs to orderα*** had found theα_(s)^(4)order correction to be significant and conjectured that theα_(s)^(4)order corrections might also be *** et *** corrected theα_(s)^(4)-order *** have extended the analytic calculations to orderαs4;it involves an unknown constant K3 which occurs inαs4 *** order to estimate the effect ofα_(s)^(4)order correction,we have chosen K3 to range from-1000 to+1000 and we find that the value of R changes by about-11%to+10%,respectively,compared to the value of R=3.5 obtained toα_(s)^(4)-order result.

关键词： correction α dynamics

Rockburst management in Canadian hard rock mines

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1036-1043页

作者： b.p.Simser Glencore’s Sudbury Integrated Nickel Operations

Rockburst is a complex mining-induced phenomenon that remains difficult to be *** particular,geological conditions contributing to rockbursts are more variable than those in many conventional engineering ***,intact rock properties,and other rock mass conditions vary,sometimes,within small *** levels that store energy or drive structures can change with geological *** example,faults may channel stress between the void and the discontinuity,and/or alter the local stress ***-strength rock masses may be very massive at shallow depth,allowing for large/stable *** same rock type may store excessive strain energy at depth or high mineral extraction,and lead to *** robust ground support systems that can bear dynamic loading are now commonplace in mining industry.A typical approach would be able to evaluate rockburst potential,and selectively deploy more robust ground support *** resistant support is more expensive in installation than most support systems designed for gravity ***,an excessively conservative risk assessment can affect both direct support costs and *** mines continue to go deeper,selective use of burst-prone support may not be an optimal choice,and pervasive installation may become *** implies a need to maintain a reasonable installation speed,and the time to get to deep orebodies is a major economic *** paper shows field examples of rockbursts to highlight some of the complex issues related to the rockburst.A multi-tiered risk mitigation approach is used for rockburst *** of risk reduction strategies are given and some examples from a deep hard rock mine are used to illustrate the relative success of the *** that some residual risks to worker safety remain,discussion is presented on where more research or process improvements would be beneficial.

关键词： Rockburst Dynamic support Seismic monitoring

Evolution of the paleogene succession of the western Himalayan foreland basin

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2013年第2期4卷 199-212页

作者： b.p.Singh CAS in Geology.banaras Hindu University

The paleogene succession of the Himalayan foreland basin is immensely important as it preserves evidence of India-Asia collision and related records of the Himalayan *** this paper,the depositional regime of the paleogene succession of the Himalayan foreland basin and variations in composition of the hinterland at different stages of the basin developments are *** paleogene succession of the western Himalayan foreland basin developed in two stages,*** stage and post-collisional *** the onset,chert breccia containing fragments derived from the hanging walls of faults and reworked bauxite developed as a result of erosion of the forebulge. The overlying early Eocene succession possibly deposited in a coastal system,where carbonates represent barriers and shales represent ***-section,the middle Eocene marl beds likely deposited on a tidal *** late Eocene/Oligocene basal Murree beds,containing tidal bundles,indicate that a mixed or semi-diurnal tidal system deposited the sediments and the sedimentation took place in a tidedominated *** the higher-up,the succession likely deposited in a river-dominated estuary or in meandering *** the beginning of the basin evolution,the sediments were derived from the precambrian basement or from the metasediments/volcanic rocks possessing terrains of the *** early and middle Eocene（54.7-41.3 Ma） succession of the embryonic foreland possibly developed from the sediments derived from the Trans-Himalayan schists and phyllites and Indus ophiolite of the north during syn-collisional *** detrital minerals especially the lithic fragments and the heavy minerals suggest the provenance for the late Eocene/Oligocene sequences to be from the recycled orogenic belt of the Higher Himalaya,Tethyan Himalaya and the Indus-suture zone from the north during post-collisional *** is also supported by the paleocurrent measurements those suggest main flows directed towards sou

关键词： Facies architecture provenance basin evolution paleogene Himalayan foreland Tectonics

Contrasting REE Signatures on Manganese Ores of Iron Ore Group in North Orissa, India

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2007年第6期25卷 749-758页

作者： p.p.Mishra b.K.Mohapatra p.p.Singh Institute of Minerals and Materials Technology Bhubaneswar 751013 India post Graduate Department of Geology Utkal University Bhubaneswar 751004 India

The distribution pattern of Rare Earth Elements （REE） in three categories of manganese ores viz. stratiform, stratabound-replacement, and detrital of precambrian Iron Ore Group from north Orissa, India was reported. These categories of Mn-ore differed in their major and trace chemistry and exhibited contrasting REE signature. The stratiform ores were relatively enriched in ∑REE content （697 μg·g^-1） and their normalized pattern showed both positive Ce and Eu anomalies, whereas the stratabound-replacement types were comparatively depleted in ∑REE content （211 μg·g^-1） and showed negative Ce and flat Eu signatures. The detrital categories showed mixed REE pattern. The data plotted in different discrimination diagrams revealed a mixed volcaniclastic and chemogenic source of material for stratiform categories, and LREE （Light Rare Earth Elements） and HREE （Heavy Rare Earth Elements） are contributed by such sources, respectively. In contrast, the stratabound ore bodies were developed during the remobilization of stratiform ores, and associated Mncontaining rocks under supergene condition followed by the redeposition of circulating mineralized colloidal solutions in structurally favorable zones. During this process, some of the constituents were found only in very low concentration within stratabound ores, and this is attributed to their poor leachability/mobility. The detrital ores did not exhibit any significant characteristic in respect of REE as their development was via a complex combination of processes involving weathering, fragmentation, recementation, and burial under soil cover.

关键词： manganese ore REE normalization geochemistry bonai-Keonjhar belt Orissa rare earths

Corrosion Inhibition of Leucaena Leucocephala pod on Mild Steel in Sulphuric Acid Solution

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 416-424页

作者： p.Muthukrishnan b.Jeyaprabha p.prakash Department of Chemistry Thiagarajar College Department of Civil Engineering Fatima Michael College of Engineering & Technology

The corrosion of the mild steel in i mol/L H2SO4 was investigated using Leucaena leucocephala pod extract （LLpE） as corrosion inhibitor by weight loss and electrochemical techniques. Inhibition efficiency of 95% was achieved with 500×10^-6 of LLpE at 308 K. The polarization studies showed that LLpE acted as mixed type inhibitor. The adsorption of the studied inhibitor on mild steel obeyed Langmuir adsorption isotherm. protective film formation against acid attack was confirmed by FT-IR, XRD and SEM techniques.

关键词： Mild steel polarization SEM Acid corrosion XRD

An ecofriendly approach for corrosion control of 6061 Al-15%(v)SiC(p)composite and its base alloy

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2017年第3期25卷 363-372页

作者： Charitha b.p. padmalatha Rao Department of chemistry Manipal Institute of TechnologyManipalUdupiKamatakaIndia

Corrosion inhibition characteristics of bio polymer dextran was studied for the corrosion control of 6061 Al-15%_((v)) SiC_((p)) composite and its base alloy in 1 mol·L^(-1) HCl. Standard electrochemical techniques such as potentiodynamic polarization(pDp) measurements and electrochemical impedance spectroscopy(EIS) method were adopted for corrosion rate measurement. Surface morphology was studied by scanning electron microscopy(SEM) and elemental mapping was done by energy dispersive X-ray(EDX) analysis. Suitable mechanism was proposed for corrosion and inhibition process. Results indicated that dextran acts as an excellent anticorrosive agent for the corrosion control of 6061 Al-15%_((v)) SiC_((p)) composite, with maximum inhibition efficiency of 91% for the concentration of 0.4 g·L^(-1) at 303 K. Dextran acted as a mixed type of inhibitor, and got physically adsorbed both on composite and base alloy by obeying Langmuir adsorption isotherm. Dextran is proved to be a green inhibitor with environmental and economic benefits.

关键词： 6061 Al-15%(v) SiC(p) composite Green inhibitor biopolymer Electrochemical studies SEM–EDX

Quasielastic Electron Scattering from ^(12)C

在线全文

学校读者我要写书评

暂无评论

Chinese physics Letters 1997年第5期14卷 321-324页

作者： LU pao b.p.Nigam Department of physics and Astronomy Arizona State UniversityBox 871504TempeAZ 85287-1504U.S.A National Center of High performance Computing P.O.Box 19-136Hsim ChuTaiwan

Transverse electron scattering response function S_(T)(q,ω)has been calculated by using a hard core common harmonic oscillator *** agreement is obtained with the experimental date at q=400 MeV/c.

关键词： potential. Electron harmonic

Electrical properties of rare earth based tungsten bronze vanadates

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2012年第11期30卷 1134-1137页

作者： b.b.Mohanty p.S.Sahoo R.N.p.Choudhary Department of physics Betnoti College Betnoti Department of physics ITER

barium based tungsten bronze （Tb） oxides having high dielectric constant and low loss, can be effectively used as transducers, actuators, capacitors and also in memory devices. All these characteristics stimulated the researchers to replace toxic and hazardous lead based materials by barium based Tb materials from industry. In the present research work, polycrystalline samples of baaSrRTi3VTO30 （R=Dy, Sm, La） were synthesized by a high temperature solid state reaction technique. preliminary structural （X-ray diffraction） analyses of these com- pounds showed the formation of single-phase orthorhombic structures at room temperature having average crystallite size of the order of some nanometer for all the compounds. The scanning electron micrographs （SEM） provided information on the quality of the samples and showed more or less homogeneous distribution of grains over the entire surface of the samples. Detailed dielectric study in a wide temperature range （30-500 ℃） showed ferro to para phase transition for Dy and Sm substituted samples whereas no such transition was observed for La substituted samples. both the grain and grain boundary resistances exhibited negative temperature coefficient of resistance behavior much like semiconductors. The dc conductivity of all the compounds obeyed Arrhenius relation.

关键词： ceramics X-ray diffraction dielectric properties electrical conductivity rare earths