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Pedosphere 2008年第6期18卷 749-757页

作者： k. m. ASHWINI k. r. SrIDHAr microbiology and Biotechnology Department of Biosciences Mangalore University Mangalagangotri

Seven sampling sites in each of three biomes (Western Ghats, foothills of Western Ghats and west coast) of south- western India were investigated to study the distribution, abundance and ecology of pill millipedes (Arthrosphaera) and associated fauna in relation to edaphic features. Abundance and biomass of Arthrosphaera and other.m.llipedes were the highest in Western Ghats, while earthworms were in foothills. Arthrosphaera magna and Arthrosphaera spp. were common in Western Ghats and foothills respectively, while no Arthrosphaera were found in the west coast. None of the sampling sites consisted of more than one species of Arthrosphaera. Biomass of Arthrosphaera, other.m.llipedes and earthworms significantly differed in Western Ghats (P = 9.48 × 10-7) and foothills (P = 1.35 × 10-8), as did the biomass of species of Arthrosphaera (P = 2.76 × 10-7) between Western Ghats and foothills. Correlation analysis revealed that biomass of Arthrosphaera was significantly (P = 0.01, r = 0.45) correlated with soil organic carbon rather than other edaphic fea- tures (pH, phosphate, calcium and magnesium). Distribution pattern, abundance, biomass and ecology of Arthrosphaera of Western Ghats in relation to soil qualities were compared with millipedes of other regions of the world.

关键词： Arthrosphaera distribution edaphic features pill millipedes Western Ghats

Exacerbation of Soft Tissue Lesions in Lead Exposed Virus Infected mice

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Biomedical and Environmental Sciences 2003年第4期16卷 369-378页

作者： PrATIBHAGUPTA m.m.HUSAIN rAVISHANkErt r.k.S.DOGrA P.k.SETH r.k.mAHESHWArI PrATIBHAGUPTAt VirologyLaboratory IndustrialToxicologyResearchCentreP.O.BoxNo.80MahatmaGandhiMargLucknow226001lndia Depar.m.ntofPathology UniformedServicesUniversityofHealthSciences4301JonesBridgeRoadBethesdaMD20814USA

Objective To investigate the effect of Lead (Pb) acetate exposure on Semliki forest virus (SFV) pathogenesis in mice. methods Different doses (62.5, 125, 250 and 500 mg/kg body weight) of Pb dissolved in normal saline were given to mice by oral intubation in a sub-acute (28 days) and sub-chronic (90 days) regimen followed by SFV infection. morbidity, mortality, clinical symptoms, mean survival time (mST), changes in body and organ weight, accumulation of lead in soft tissues, virus titre in brain and histopathological alterations were compared between lead exposed and infected groups. results Early appearance of virus symptoms, increased mortality, decreased mST, enhanced SFV titre and greater tissue damage were observed in lead exposed-SFV-infected mice. Conclusion Pre-exposure to lead increases the susceptibility of mice towards SFV infection. Further studies are suggested in view of the persistence of lead in the environment and the possibility of infection by microbial pathogens.

关键词： Lead acetate Exposure Sub-acute Sub-chronic SFV Pathogenicity

An ab initio investigation of vibrational, thermodynamic, and optical properties of Sc_2AlC mAX compound

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Chinese Physics B 2016年第10期25卷 103-108页

作者： m A Ali m T Nasir.m.r khatun A k m A Islam S H Naqib Depar.m.nt of Physics Chittagong University of Engineering and Technology Depar.m.nt of Arts & Sciences Bangladesh Army University of Science and Technology Depar.m.nt of Physics University of Rajshahi International Islamic University Chittagong

The structural vibrational, thermodynamical, and optical properties of potentially technologically important, weakly coupled mAX compound, Sc2 Al C are calculated using density functional theory(DFT). The structural properties of ScAlC are compared with the results reported earlier. The vibrational, thermodynamical, and optical properties are theoretically estimated for the first time. The phonon dispersion curve is calculated and the dynamical stability of this compound is investigated. The optical and acoustic modes are observed clearly. We calculate the Helmholtz free energy(F), internal energy(E), entropy(S), and specific heat capacity(Cv) fr.m.the phonon density of states. Various optical par.m.ters are also calculated. The reflectance spectr.m.shows that this compound has the potential to be used as an efficient solar reflector.

关键词： mAX compound phonon dispersion thermodynamical properties optical properties

Lattice expansion and smaller CuO_(x)CeO_(2-δ)particles formation by magnesium interaction for low temperature CO oxidation

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Journal of rare Earths 2021年第4期39卷 434-439页

作者： J.m.Waikar r.k.more N.r.Lavande P.m.more Depar.m.nt of Chemistry Institute of Chemical TechnologyMatungaMumbai400019India

A series of magnesia doped CuOxCeO_(2-δ)catalysts were prepared by co-precipitation followed by impregnation method and investigated for CO *** manuscript is devoted to explaining the role of mgO for the formation of active species on the CuOxCeO_(2-δ)*** improvement in catalytic activity is ascribed to the formation of various active species due to the interaction of magnesia with CuOxCeO_(2-δ).The catalysts were characterized by PXrD,N_(2)adsorption,H_(2)-TPr,XPS,SEm,EDS and HrTEm *** mg doped catalyst shows lattice expansion of ceria due to the formation of smaller Ce^(3+)species with oxygen *** mg-O bond also takes part in CO activation and oxidation,which results in the increase of CO *** mg doped CuOxCeO_(2-δ)catalyst shows improvement in low temperature activity compared with the CuOxCeO_(2-δ).

关键词： Adsorbed oxygen Lattice expansion Low temperature oxidation Ce^(3+) Cu^(+) rare earths

A discrete model for prediction of radon flux fr.m.fractured rocks

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Journal of rock mechanics and Geotechnical Engineering 2018年第5期10卷 879-892页

作者： k.m. Ajayi k. Shahbazi r Tukkaraja k. katzenstein Depar.m.nt of mechanical Engineering South Dakota School of Mines and Technology Rapid City SD 57701 USA b Depar.m.nt of mining Engineering and management South Dakota School of Mines and Technology Rapid City SD 57701 USA Depar.m.nt of Geology and Geological Engineering South Dakota School of Mines and Technology Rapid City SD 57701 USA

Prediction of radon flux fr.m.the fractured zone of a propagating cave mine is basically associated with uncertainty and complexity. For instance, there is restricted access to these zones for field measure- ments, and it is quite difficult to replicate the complex nature of both natural and induced fractures in these zones in laboratory studies. Hence, a technique for predicting radon flux fr.m.a fractured rock using a discrete fracture network （DFN） model is developed to address these difficulties. This model quantifies the contribution of fractures to the total radon flux, and estimates the fracture density fr.m.a measured radon flux considering the effects of advection, diffusion, as well as radon generation and decay. radon generation and decay are classified as reaction processes. Therefore, the equation solved is termed as the advection-diffusion-reaction equation （ADrE）. Peclet number （Pe）, a conventional dimensionless par.m.ter that indicates the ratio of mass transport by advection to diffusion, is used to classify the transport regimes. The results show that the proposed model effectively predicts radon flux fr.m.a fractured rock. An increase in fracture density for a rock sample with uniformly distributed radon generation rate can elevate radon flux significantly compared with another rock sample with an equivalent increase in radon generation rate. In addition to Pe, two other independent dimensionless par.m.ters （derived for radon transport through fractures） significantly affect radon dimensionless flux. Findings provide insight into radon transport through fractured rocks and can be used to improve radon control measures for proactive mitigation.

关键词： radon mass flux radon dimensionless flux Stochastic model Discrete fracture network (DFN) Caving mining method Fractured rocks

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural regeneration research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes fr.m.the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting fr.m.stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

A survey of sub-inhibitory concentrations of antibiotics in the environment

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Journal of Environmental Sciences 2021年第1期33卷 21-27页

作者： Louise k.m.Chow Timothy m.Ghaly michael r.Gillings Depar.m.nt of Biological Sciences Macquarie UniversityNSW 2109Australia ArC Centre of Excellence in Synthetic Biology Macquarie UniversityNSW 2109Australia

Antibiotics are poorly metabolized,and can enter the environment via human waste streams,agricultural run-off and pharmaceutical *** consequently expect to see a concentration gradient of antibiotic compounds radiating fr.m.areas of human *** antibiotics should be thought of as pollutants,as they can accumulate,and have biological *** antibiotic pollutants can increase rates of mutation and lateral transfer events,and continue to exert selection pressure even at sub-inhibitory ***,we conducted a literature survey on environmental concentrations of *** collated 887 data points fr.m.40 peer-reviewed *** then determined whether these concentrations were biologically relevant by comparing them to their.m.nimum selective concentrations,usually defined as between 1/4 and 1/230 of the minimum inhibitory *** concentrations of antibiotics surveyed often fall into this *** general,the antibiotic concentrations recorded in aquatic and sediment samples were *** findings indicate that environmental concentrations of antibiotics are likely to be influencing microbial ecology,and to be driving the selection of antibiotic resistant bacteria.

关键词： Antimicrobial Pollution Evolution microorganism Environment Antibiotic resistance

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QUArk mASSES

Chinese Physics C 2016年第10期40卷 653-660页

作者： A.V. manohar C.T. Sachrajda r.m. Barnett University of California San Diego University of Southampton LBNL

A. Introduction This note discusses some of the theoretical issues relevant for the determination of quark masses, which are fundamental par.m.ters of the Standard model of particle physics. Unlike the leptons, quarks are confined inside hadrons and are not observed as physical particles. Quark masses therefore cannot be measured directly, but must be determined indirectly through their influence on hadronic properties. Although one often speaks loosely of quark masses as one would of the mass of the electron or.m.on, any quantitative statement about the value of a quark mass must make careful reference to the particular theoretical fr.m.work that is used to define it. It is important to keep this scheme dependence in mind when using the quark mass values tabulated in the data listings.

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Large time asymptotics for solutions to a nonhomogeneous Burgers equation

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Applied mathematics and mechanics(English Edition) 2010年第9期31卷 1189-1196页

作者： S.r.CHIDELLA m.k.YADAV Depar.m.nt of mathematics Indian Institute of Technology Madras

In this article, the solutions to a nonhomogeneous Burgers equation subject to bounded and compactly supported initial profiles are constructed. In an interesting study, kloosterziel （Journal of Engineering mathematics 24, 213-236 （1990）） represented a solution to an initial value problem （IVP） for the heat equation, with an initial data in a class of rapidly decaying functions, as a series of self-similar solutions to the heat equation. This approach quickly revealed the large time behaviour for the solution to the IVP. Inspired by kloosterziel＇s approach, the solution to the nonhomogeneous Burgers equation is expressed in terms of the self-similar solutions to the heat equation. The large time behaviour of the solutions to the nonhomogeneous Burgers equation is obtained.

关键词： nonhomogeneous Burgers equation Hermite polynomials self-similar solutions

An Overview of the Geoenvironmental Status of the kullu Valley, Himachal Pradesh, India

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Journal of mountain Science 2007年第1期4卷 3-23页

作者： m.P. Sah r.k mazari Wadia Institute of Himalayan Geology33 Gen. Mahadeo Singh Road Dehra Dun-248001 India

The north-south trending kullu valley between rohtang in the north and Hansu in the south is a wide and open valley filled with Quaternary sediments along the main eourse of the Beas river. The valley in the middle is drained by the Beas river and numerous tributaries join it laterally. The tributary ehannels have deposited large alluvial fans at their.m.uths whieh form three distinct levels. The Beas river has deposited alluvial terraees, whieh are very distinct towards the lower reaehes and form three to four levels. The upper slopes and high altitudinal areas are eovered with periglaeial and glaeial deposits. The terraee, fan and hill slopes have provided an ideal geoenvironment for human aetivities inehiding agrieulture, hortieulture, dense settlements and other eivil establishments. The kulhi Valley is prone to various natural hazards, flash floods and eloudbursts that are very eommon in this valley due to its peeuliar geomorphie eonclifton, high relief of peripheral ridges and impact of monsoon winds. The studies carried out so far indicate that the losses caused by these phenomena both in terms of life and property are mainly due to unwise human interaction with the geoenvironment of the area. The paper gives an overview of the geoenvironmental status of the kulhi Valley and suggests the necessity of undertaking further detailed studies ineluding resouree mapping for balaneed development of the area.

关键词： Geoenvironment kullu Valley geomorphology natural hazard climate