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Applied Mathematics and Mechanics(English Edition) 2015年第12期36卷 1593-1610页

作者： S.DAS S.CHAKrABOrTY r.n.jana O.D.MAKInDE Department of Mathematics University of Gour Banga Department of Applied Mathematics Vidyasagar University Faculty of Military Science Stellenbosch University

The unsteady laminar magnetohydrodynamics （MHD） boundary layer flow and heat transfer of nanofluids over an accelerating convectively heated stretching sheet are numerically studied in the presence of a transverse magnetic field with heat source/sink The unsteady governing equations are solved by a shooting method with the runge-Kutta- Fehlberg scheme. Three different types of water based nanofluids, containing copper, aluminium oxide, and titanium dioxide, are taken into consideration. The effects of the pertinent parameters on the fluid velocity, the temperature, the entropy generation num- ber, the Bejan number, the shear stress, and the heat transfer rate at the sheet surface are graphically and quantitatively discussed in detail. A comparison of the entropy generation due to the heat transfer and the fluid friction is made with the help of the Bejan number. It is observed that the presence of the metallic nanoparticles creates more entropy in the nanofluid flow than in the regular fluid flow.

关键词： unsteady MHD flow nanofluid heat source/sink entropy generation Bejan number

Hydromagnetic flow between two porous disks rotating about non-coincident axes

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Acta Mechanica Sinica 2008年第5期24卷 489-496页

作者： M.Guria B.K.Das r.n.jana C.Erdem Imrak Department of Applied Mathematics Vidyasagar UniversityMidnapore 721 102West BengalIndia Department of Mechanical Engineering Istanbul Technical UniversityGumussuyuIstanbul 34439Turkey

Hydromagnetic flow between two porous disks rotating with same angular velocity Ω about two noncoincident axes has been studied in the presence of a uniform transverse magnetic field. An exact solution of the governing equations has been obtained in a closed form. It is found that the primary velocity f/Ωl increases and the secondary velocity g/Ωl decreases with increase in either reynolds number re or the Hartman number M. It is also found that the torque at the disk η= 0 increases with increase in either M^2 or K^2. On the other hand there is no torque at the disk η= 1 for large M^2 and K^2. The heat transfer characteristic has also been studied on taking viscous and Joule dissipation into account. It is seen that the temperature increases with increase in either M^2 or K^2. It is found that the rate of heat transfer at the disk η= 0 increases with increase in either M or K. On the other hand the rate of heat transfer at the disk η= 1 increases with increase in K but decreases with increase in M.

关键词： non-coincident Viscous fluid Torque ,Hydromagnetic

Hall effects on hydromagnetic flow on an oscillating porous plate

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Applied Mathematics and Mechanics(English Edition) 2009年第4期30卷 503-512页

作者： S.L.Maji A.K.Kanch M.Guria r.n.jana Department of Applied Mathematics Vidyasagar University

In this paper, an analysis is made on the unsteady flow of an incompressible electrically conducting viscous fluid bounded by an infinite porous flat plate. The plate executes harmonic oscillations at a frequency n in its own plane. A uniform magnetic field Ho is imposed perpendicular to the direction of the flow. It is found that the solution also exists for blowing at the plate. The temperature distribution is also obtained by taking viscous and Joule dissipation into account. The mean wall temperature θo（O） decreases with the increase in the Hall parameter m. It is found that no temperature distribution exists for the blowing at the plate.

关键词： Hall effects oscillation resonance heat transfer and mean temperature

Flash sintering incubation kinetics

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npj Computational Materials 2020年第1期6卷 850-857页

作者： K.S.n.Vikrant Han Wang Aniruddha jana Haiyan Wang r.Edwin García School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907USA

The microstructural mechanisms leading to onset of the flash sintering are demonstrated experimentally and theoretically for Yttria Stabilized Zirconia,*** regimes leading to flash event are identified:(1)radiation-dominated regime,where the oven controls the heating of the sintered sample,and a small subset of particle-particle contacts and surfaces of the green body define percolative paths for the charge to flow along and across the interfaces;(2)Transition regime,where charge transport is suppressed across particle contact misorientations and deflects to surficial and small angle particle contact *** a result,internal Joule heating takes over externally-driven radiation ***,(3)Percolative regime,where the concentration of oxygen vacancies drastically increases at particle contacts,surfaces,and triple junctions,and enables charge to flow through multiple paths,generating large amounts of Joule heating,resulting in the onset of a flash *** validated theory sets the stage to rationalize the microstructural evolution and charge transport on a ceramic green body during flash sintering.

关键词： flash Flash regime

The Paleoarchean northern Mundo novo Greenstone Belt,São Francisco Craton:Geochemistry,U-Pb-Hf-O in zircon and pyriteδ^(34)S-Δ^(33)S-Δ^(36)S signatures

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Geoscience Frontiers 2022年第5期13卷 190-206页

作者： Guilherme S.Teles Farid Chemale Jr. janaína n.Ávila Trevor r.Ireland Unidade Acadêmica de Mineração e Geologia Universidade Federal de Campina GrandeCampina GrandeBrazil Programa de Pós-Graduação em Geologia Universidade de BrasíliaBrasíliaBrazil Programa de Pós-Graduação em Geologia Universidade do Vale do Rio dos SinosSão LeopoldoBrazil research School of Earth Sciences The Australian National UniversityCanberraACT 2601Australia Griffith Centre for Social and Cultural research Griffith UniversityNathanQueensland 4111Australia

Greenstone belts contain several clues about the evolutionary history of primitive ***,we describe the volcano-sedimentary rock association exposed along the eastern margin of the Gavião Block,named the northern Mundo novo Greenstone Belt(n-MnGB),and present data collected with different techniques,including U–Pb–Hf–O isotopes of zircon and multiple sulfur isotopes(^(32)S,^(33)S,^(34)S,and ^(36)S)of pyrite from this supracrustal sequence.A pillowed metabasalt situated in the upper section of the n-MnGB is 3337±25 Ma old and has zircon with ε_(Hf)(t)=2.47 to1.40,Hf model ages between 3.75 Ga and 3.82 Ga,and δ^(18)O=+3.6‰to+7.3‰.These isotopic data,together with compiled whole-rock trace element data,suggest that the mafic metavolcanic rocks formed in a subduction-related setting,likely a back-arc basin juxtaposed to a continental *** this context,the magma interacted with older Eoarchean crustal components from the Gavião *** zircons from the overlying quartzites of the Jacobina Group are sourced from Paleoarchean rocks,in accordance with previous studies,yielding a maximum depositional age of 3353±22 *** detrital zircons have ε_(Hf)(t)=5.40 to0.84,Hf model ages between 3.66 Ga and 4.30 Ga,and δ^(18)O=+4.8‰to+6.4‰.The pyrite multiple sulfur isotope investigation of the 3.3 Ga supracrustal rocks from the n-MnGB enabled a further understanding of Paleoarchean sulfur *** samples have diverse isotopic compositions that indicate sulfur sourced from distinct ***,they preserve the signal of the anoxic Archean atmosphere,expressed by MIF-S signatures(Δ^(33)S between1.3‰to+1.4‰)and a Δ^(36)S/Δ^(33)S slope of0.81 that is indistinguishable from the so-called Archean array.A BIF sample has a magmatic origin of sulfur,as indicated by the limited Δ^(34)S range(0 to+2‰),Δ^(33)S~0‰,and Δ^(36)S~0‰.A carbonaceous schist shows positive Δ^(34)S(2.1‰–3.5‰)and elevated Δ^(33)S(1.2‰–1.4‰)values,with corresponding negative Δ^(36)S

关键词： northern Mundo novo Greenstone Belt Multiple sulfur isotopes Geochronology Paleoarchean Gavião Block São Francisco Craton

role of forests in headwater control with changing environment and society

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International Soil and Water Conservation research 2021年第1期9卷 143-157页

作者： Josef Krecek jana nováková Ladislav Palán Eva Pazourková Evzen Stuchlík Department of Hydrology Czech Technical University in PragueThákurova 7CZ-16629Prague 6Czech Republic Independent Botanist Na Vrcholu 4CZ-13000PragueCzech Republic AOn Impact Forecasting Václavskénáměstí19CZ-11000PragueCzech Republic Institute of Hydrobiology Biology CentreCzech Academy of SciencesNa Sádkách 7CZ-37005(C)eskéBudějoviceCzech Republic

Forest practices in headwater catchments are related to environmental and social *** aim of this study is to analyse the changing protective functions of forests in the upper plain of the Jizera Mts.(north Bohemia,Czech republic)since the second half of the 19th *** time,forests have gradually changed from native stands to spruce plantations(Picea abies),introducing exotic conifers(more resistant to air pollution),and,recently,back to more diverse mixed *** priority in pro-tective forest functions there shifted from flood protection to integrated control of water resources(quantity and quality).In the 1980s,forest-water interactions were degraded by consequences of extreme acid atmospheric deposition,forest die-back,and extensive *** the Jizerka catchment,first signs of recovery were observed in the early *** waters there are still affected by prolonged *** reconstruction of stream water chemistry at Jizerka follows the drop of the acid deposition in some 5 years,the revival of stream biota takes 10-15 *** 2071-2100,the pro-jected climate change shows rising annual air temperatures by 3.0-4.6℃,decreasing water yield by 65-123 mm,60%drop in'minimum residual discharge',and 20-30%rise in ***,these projected environmental changes cannot substantially decline the high potential in water resource recharge,or,start reverse processes in recent recovery from acidification and radically affect the exis-tence of planned mixed forests in the upper plain of the Jizera Mts.

关键词： Headwater catchment Forest functions Water resource recharge Acid atmospheric deposition Climate change

SFrP4 expression correlates with epithelial mesenchymal transitionlinked genes and poor overall survival in colon cancer patients

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World Journal of Gastrointestinal Oncology 2019年第8期11卷 589-598页

作者： Landry E nfonsam jana Jandova Hunter C Jecius Pamela n Omesiete Valentine n nfonsam Department of Genetics Children’s Hospital of Eastern OntarioOttawaOntario K1H 8L1Canada Department of Surgery University of ArizonaTucsonAZ 85724United States

BACKGrOUnD Colon cancer is among the most commonly diagnosed cancers in the United States with an estimated 97220 new cases expected by the end of *** affects 1.2 million people around the world and is responsible for about 0.6 million deaths every *** decline in overall incidence and mortality over the past 30 years,there continues to be an alarming rise in early-onset colon cancer cases(rs).Patients are often diagnosed at late stages of the disease and tend to have poor *** previously showed that the WnT“gatekeeper”gene,secreted frizzled-related protein 4(SFrP4),is over-expressed in early-onset colon ***4 is speculated to play an essential role in cancer by inhibiting the epithelial mesenchymal transition(EMT).AIM To investigate the correlation between SFrP4 expression and EMT-linked genes in colon cancer and how it affects patient *** SFrP4 expression relative to that of EMT-linked genes and survival analysis were performed using the University of California Santa Cruz Cancer Browser *** SFrP4 was found to be co-expressed with the EMT-linked markers CDH2,Fn1,VIM,TWIST1,TWIST2,SnAI1,SnAI2,ZEB1,ZEB2,POSTn,MMP2,MMP7,MMP9,and ***4 expression negatively correlated with the EMTlinked suppressors CLDn4,CLDn7,TJP3,MUC1,and *** expression of SFrP4 and the EMT-linked markers was higher in mesenchymal-like samples compared to epithelial-like samples which potentially implicates SFrP4-EMT mechanism in colon ***,patients overexpressing SFrP4 presented with poor overall survival(P=0.0293).COnCLUSIOn Considering the implication of SFrP4 in early-onset colon cancer,particularly in the context of EMT,tumor metastasis,and invasion,and the effect of increased expression on colon cancer patient survival,SFrP4 might be a potential biomarker for early-onset colon cancer that could be targeted for diagnosis and/or disease therapy.

关键词： Secreted frizzled-related protein 4 Epithelial mesenchymal transition Colon cancer Survival

Expanding through the Emerald Isle:exploration and spatial orientation of non-native bank voles in Ireland

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Current Zoology 2024年第3期70卷 320-331页

作者： Valeria Mazza jana A.Eccard Animal Ecology Institute for Biochemistry and BiologyUniversity of PotsdamMaulbeerallee 114469PotsdamGermany and Department of Ecological and Biological Sciences University of TusciaLargo dell'Università10100 ViterboItaly

Whether introduced into a completely novel habitat or slowly expanding their current range,the degree to which animals can effciently explore and navigate new environments can be key to survival,ultimately determining population establishment and colonization *** tested whether spatial orientation and exploratory behavior are associated with non-native spread in free-living bank voles(Myodes glareolus,n=43)from a population accidentally introduced to Ireland a century *** measured spatial orientation and navigation in a radial arm maze,and behaviors associated to exploratory tendencies and risk-taking in repeated open-feld tests,at the expansion edge and in the source *** voles at the expansion edge re-visited unrewarded arms of the maze more,waited longer before leaving it,took longer to start exploring both the radial arm maze and the open feld,and were more risk-averse compared to conspecifcs in the source *** together,results suggest that for this small mammal under heavy predation pressure,a careful and thorough exploration strategy might be favored when expanding into novel environments.

关键词： animal personality biological invasions exploration behavior Myodes glareolus range expansion spatial orientation.

Development of internal COI primers to improve and extend barcoding of fruit flies (Diptera: Tephritidae: Dacini)

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Insect Science 2020年第1期27卷 143-158页

作者： Matt n.Krosch Francesca Strutt Mark J.Blacket jana Batovska Melissa Starkie Anthony r.Clarke Stephen L.Cameron Mark K.Schutze School of Earth Environmental&Biological SciencesQueensland University of TechnologyBrisbaneQueenslandAustralia Plant Biosecurity Co-operative research Centre BruceAustralian Capital TerritoryAustralia Agriculture Victoria AgriBioCentre for AgriBioscienceBundooraVictoriaAustralia Department of Entomology Purdue UniversityWest LafayetteIndianaUSA Department of Agriculture&Fisheries Queensland Primary Industries Insect Collection(QDPC)Dutton ParkQueenslandAustralia

Accurate species-level identifications underpin many aspects of basic and applied biology;however,identifications can be hampered by a lack of discriminating morphological characters,taxonomic expertise or *** approaches,such as DnA"barcoding"of the cytochrome c oxidase(COI)gene,are argued to overcome these ***,nuclear encoding of mitochondrial genes(numts)and poor amplification success of suboptimally preserved specimens can lead to erroneous *** insect group for which these molecular and morphological problems are significant are the dacine fruit flies(Diptera:Tephritidae:Dacini).We addressed these issues associated with COI barcoding in the dacines by first assessing several"universal"COI primers against public mitochondrial genome and numt sequences for dacine *** then modified a set of four primers that more closely matched true dacine COI sequence and amplified two overlapping portions of the COI barcode *** new primers were tested alongside universal primers on a selection of dacine species,including both fresh preserved and decades-old dry ***,Bactrocera tiyoni mitochondrial and nuclear genomes were compared to identify putative *** numt clades were identified,three of which were amplified using existing universal *** contrast,our new primers preferentially amplified the"true"mitochondrial COI barcode in all dacine species *** new primers also successfully amplified partial barcodes from dry specimens for which full length barcodes were *** we recommend these new primers be incorporated into the suites of primers used by diagnosticians and quarantine labs for the accurate identification of dacine species.

关键词： Bactrocera biosecurity Dacus\minibarcodes pseudogene Zeugodacus

Evaluation of natural forest regeneration as a part of land restoration in the Khentii massif,Mongolia

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Journal of Forestry research 2020年第5期31卷 1773-1786页

作者： David Juricka Antonın Kusbach jana Parılkova Jakub Houska Pavlına Ambrozova Vaclav Pecina Zdena rosicka Martin Brtnicky Jindrich Kynicky Department of Geology and Pedology Faculty of Forestry and Wood TechnologyMendel UniversityZemedelska 161300 BrnoCzech Republic Department of Forest Botany Dendrology and GeobiocoenologyFaculty of Forestry and Wood TechnologyMendel UniversityZemedelska161300 BrnoCzech Republic Faculty of Civil Engineering Institute of Water StructuresBrno University of TechnologyZizkova 1760200 BrnoCzech Republic Central European Institute of Technology Brno University of TechnologyPurkynova 656/12361200 BrnoCzech Republic

Forest stands in the semi-arid environment of northern Mongolia have an essential role in controlling ongoing desertification in the surrounding *** the last decade,the total forest area has decreased *** aim of this study was to evaluate the potential of natural regeneration as an essential element for ensuring sustainability of these *** on field measurements from 120 plots in six sites,our assessment tool revealed five qualitative categories of forest regeneration,allowing us to assess impacts of both grazing and environmental conditions on the regeneration *** is a crucial factor and adversely affects *** sites with relatively low grazing intensity,low soil moisture levels represent the main reason for reduced *** approach to classification proposed in this study allows for the identification and interpretation of stand conditions where natural regeneration has *** study provides an important foundation to inform decisionmaking related to land protection and restoration *** findings could be used in comparative studies and,importantly,may aid further mapping of Mongolian forests.

关键词： Mongolia natural forest regeneration Seedlings Larix sibirica Land restoration Desertification