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Geo-Spatial Information Science 2019年第4期22卷 251-264,I0003页

作者： Yunzhe liu Alex Singleton Daniel Arribas-bel Geographic Data Science lab Department of Geography and PlanningUniversity of LiverpoolLiverpoolUK

A geodemographic classification aims to describe the most salient characteristics of a small area zonal geography.However,such representations are influenced by the methodological choices made during their construction.Of particular debate are the choice and specification of input variables,with the objective of identifying inputs that add value but also aim for model parsimony.Within this context,our paper introduces a principal component analysis(PCA)-based automated variable selection methodology that has the objective of identifying candidate inputs to a geodemographic classification from a collection of variables.The proposed methodology is exemplified in the context of variables from the UK 2011 Census,and its output compared to the Office for National Statistics 2011 Output Area Classification(2011 OAC).Through the implementation of the proposed methodology,the quality of the cluster assignment was improved relative to 2011 OAC,manifested by a lower total withincluster sum of square score.Across the UK,more than 70.2%of the Output Areas(OAs)occupied by the newly created classification(i.e.AVS-OAC)outperform the 2011 OAC,with particularly strong performance within Scotland and Wales.

关键词： Geodemographics variable selection UK census spatial data mining principal component analysis

In situ neutron diffraction unravels deformation mechanisms of a strong and ductile Fe Cr Ni medium entropy alloy

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journal of Materials Science & Technology 2022年第21期116卷 103-120页

作者： l.Tang F.Q.jiang j.S.Wróbel B.liu S.Kabra R.X.Duan j.H.luan Z.B.jiao M.M.Attallah D.Nguyen-Manh B.Cai School of Metallurgy and Materials University of BirminghamB152TTUnited Kingdom Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Faculty of Materials Science and Engineering Warsaw University of Technologyul.Wołoska 141Warsaw 02-507Poland State Key laboratory for Powder Metallurgy Central South UniversityChangsha 410083China Rutherford Appleton laboratory ISIS FacilityDidcot OX110QXUnited Kingdom Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomHong KongChina CCFE United Kingdom Atomic Energy AuthorityAbingdonOxfordshire OX143DBUnited Kingdom

We investigated the mechanical and microstructural responses of a high-strength equal-molar medium entropy FeCrNi alloy at 293 and 15 K by in situ neutron diffraction testing.At 293 K,the alloy had a very high yield strength of 651±12 MPa,with a total elongation of 48%±5%.At 15 K,the yield strength increased to 1092±22 MPa,but the total elongation dropped to 18%±1%.Via analyzing the neutron diffraction data,we determined the lattice strain evolution,single-crystal elastic constants,stacking fault probability,and estimated stacking fault energy of the alloy at both temperatures,which are the critical parameters to feed into and compare against our first-principles calculations and dislocation-based slip system modeling.The density functional theory calculations show that the alloy tends to form shortrange order at room temperatures.However,atom probe tomography and atomic-resolution transmission electron microscopy did not clearly identify the short-range order.Additionally,at 293 K,experimental measured single-crystal elastic constants did not agree with those determined by first-principles calculations with short-range order but agreed well with the values from the calculation with the disordered configuration at 2000 K.This suggests that the alloy is at a metastable state resulted from the fabrication methods.In view of the high yield strength of the alloy,we calculated the strengthening contribution to the yield strength from grain boundaries,dislocations,and lattice distortion.The lattice distortion contribution was based on the Varenne-luque-Curtine strengthening theory for multi-component alloys,which was found to be 316 MPa at 293 K and increased to 629 MPa at 15 K,making a significant contribution to the high yield strength.Regarding plastic deformation,dislocation movement and multiplication were found to be the dominant hardening mechanism at both temperatures,whereas twinning and phase transformation were not prevalent.This is mainly due to the high stacking fault energy of the alloy as estimated to be

关键词： Medium entropy alloy Multi-component alloy Cryogenic temperature Neutron diffraction

Quantification of corneal neovascularization after ex vivo limbal epithelial stem cell therapy

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International journal of Ophthalmology(English edition) 2014年第6期7卷 988-995页

作者： Adriano Guarnieri javier Moreno-Monta?és belén Alfonso-Bartolozzi Alfonso l.Sabater María García-Guzmán Enrique j.Andreu Felipe Prosper Department of Ophthalmology Clínica Universidad de Navarra Department of Cell Therapy Clínica Universidad de Navarra

AIM: To assess cultured limbal epithelial stem cell transplantation in patients with limbal stem cell deficiency by analyzing and quantifying corneal neovascularization.METHODS: This retrospective, interventional case series included eight eyes with total limbal stem cell deficiency. Ex vivo limbal epithelial stem cells were cultured on human amniotic membrane using an animalfree culture method. The clinical parameters of limbal stem cell deficiency, impression cytology, and quantification of corneal neovascularization were evaluated before and after cultured limbal stem cell transplantation. The area of corneal neovascularization,vessel caliber(VC), and invasive area(IA) were analyzed before and after stem cell transplantation by image analysis software. Best-corrected visual acuity(BCVA),epithelial transparency, and impression cytology were also measured.RESUlTS: One year after surgery, successful cases showed a reduction(improvement) of all three parameters of corneal neovascularization [neovascular area(NA), VC, IA], while failed cases did not. NA decreased a mean of 32.31%(P =0.035), invasion area29.37%(P =0.018) and VC 14.29%(P =0.072). BCVA improved in all eyes(mean follow-up, 76 ±21mo).Epithelial transparency improved significantly from 2.00 ±0.93 to 0.88±1.25(P =0.014). Impression cytology showed that three cases failed after limbal epithelial stem cell therapy before 1y of follow-up.CONClUSION: This method of analyzing andmonitoring surface vessels is useful for evaluating the epithelial status during follow-up, as successful cases showed a bigger reduction in corneal neovascularization parameters than failed cases. Using this method,successful cases could be differentiated from failed cases.

关键词： limbal stem cell corneal neovascularization stem cell therapy impression cytology limbal stem cell deficiency

Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research(International) 2022年第5期29卷 819-835页

作者： j.l.Guo T.j.Chen State Key laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were investigated.The results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more easily.The softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface layer.These vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing force.It is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is weakened.These behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

Convective flow of jeffrey nanofluid along an upright microchannel with Hall current and Buongiorno model:an irreversibility analysis

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1613-1628页

作者： l.ANITHA B.j.GIREESHA Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics Adichunchanagiri Institute of TechnologyChikkamagaluru 577102India

The thermal properties and irreversibility of the jeffrey nanofluid through an upright permeable microchannel are analyzed by means of the Buongiorno model.The effects of the Hall current,exponential space coefficient,nonlinear radiation,and convective and slip boundary conditions on the jeffrey fluid flow are explored by deliberating the buoyant force and viscous dissipation.The non-dimensionalized equations are obtained by employing a non-dimensional system,and are further resolved by utilizing the shooting approach and the 4th-and 5th-order Runge-Kutta-Fehlberg approaches.The obtained upshots conclude that the amplified Hall parameter will enhance the secondary flow profile.The improvement in the temperature parameter directly affects the thermal profile,and hence the thermal field declines.A comparative analysis of the Newtonian fluid and non-Newtonian fluid(jeffrey fluid)is carried out with the flow across a porous channel.In the Bejan number,thermal field,and entropy generation,the jeffrey nanofluid is more highly supported than the Newtonian fluid.

关键词： jeffrey nanofluid entropy generation exponential heat source porous medium convective and slip boundary condition

Altered expression of m^(1)A regulatory genes is associated with oncogenic pathways,overall survival,and infiltration of immune cells in diverse human cancers

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Genes & Diseases 2023年第3期10卷 739-742页

作者： Renhua Song justin j-l Wong Epigenetics and RNA Biology Program Centenary Institute The University of SydneyCamperdown 2050Australia Faculty of Medicine and Health The University of SydneyCamperdown 2050Australia

Of over 170 types of RNA modifications discovered,N^(6)-methyladenosine(m^(6)A)is the most actively studied.m6A confers oncogenic potential,maintains cancer stem cells,and is associated with cancer-related outcomes.^(... 详细信息

关键词： cancer maintain immune

Repercussion of Hall effect and nonlinear radiation on Couette-Poiseuille flow of Casson-Williamson fluid through upright microchannel

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Applied Mathematics and Mechanics(English Edition) 2022年第12期43卷 1951-1964页

作者： B.j.GIREESHA l.ANITHA Department of Post Graduation Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics Adichunchanagiri Institute of TechnologyChikkamagaluru 577102India

The main aim of the present work is to investigate the flow and heat transport properties of non-Newtonian Casson-Williamson fluid through an upright microchannel along with entropy generation analysis,and explore the effects of convective boundary conditions,Couette-Poiseuille flow,and nonlinear radiation.The movement of liquid is scrutinized with the Hall effect and exponential heat source.The rheological characteristics of the Casson-Williamson fluid model are also considered.By considering the desirable similarity variables,the equations of motion are reduced to nonlinear ordinary differential equations.The Runge-Kutta-Fehlberg fourth-fifth order method along with the shooting method is adopted to solve these dimensionless expressions.The detailed investigation is pictorially displayed to show the influence of effective parameters on the entropy generation and the Bejan number.One of the major tasks of the exploration is to compare the Casson fluid and the Williamson fluid.The results show that the rate of heat transfer in the Casson fluid is more remarkable than that in the Williamson fluid.

关键词： entropy generation Bejan number convective boundary condition Hall effect nonlinear radiation exponential heat source

Effect of periodic heat transfer on the transient thermal behavior of a convective-radiative fully wet porous moving trapezoidal fin

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Applied Mathematics and Mechanics(English Edition) 2023年第4期44卷 653-668页

作者： B.j.GIREESHA M.l.KEERTHI Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India

A moving trapezoidal profiled convective-radiative porous longitudinal fin wetted in a single-phase fluid is considered in the current article.The periodic variation in the fin base temperature is taken into account along with the temperature sensitive thermal conductivity and convective heat transfer coefficients.The modeled problem,which is resolved into a non-linear partial differential equation(PDE),is made dimensionless and solved by employing the finite difference method(FDM).The results are displayed through graphs and discussed.The effects of amplitude,frequency of oscillation,wet nature,Peclet number,and other relevant quantities on the distribution of temperature through the fin length and with the dimensionless time are investigated.It is deciphered that the periodic heat transfer gives rise to the wavy nature of the fin thermal profile against time.The analysis is beneficial in the design of fin structures for applications like solar collectors,space/airborne applications,and refrigeration industries.

关键词： convection fully wet porous fin trapezoidal profile moving fin unsteady periodic thermal condition

Shear strength behavior of geotextile/geomembrane interfaces

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journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 638-645页

作者： belén M.Bacas jorge Caizal Heinz Konietzky Terrasolum S.l.Geotechnical Engineering Technology Development Center of University of Cantabria(CDTUC) School of Civil Engineering University of Cantabria Geotechnical Institute TU Bergakademie Freiberg

This paper aims to study the shear interaction mechanism of one of the critical geosynthetic interfaces,the geotextile/geomembrane, typically used for lined containment facilities such as landfills. A largedirect shear machine is used to carry out 90 geosynthetic interface tests. The test results show a strainsoftening behavior with a very small dilatancy （〈0.5 mm） and nonlinear failure envelopes at a normalstress range of 25e450 kPa. The influences of the micro-level structure of these geosynthetics on themacro-level interface shear behavior are discussed in detail. This study has generated several practicalrecommendations to help professionals to choose what materials are more adequate. From the threegeotextiles tested, the thermally bonded monofilament exhibits the best interface shear strength underhigh normal stress. For low normal stress, however, needle-punched monofilaments are recommended.For the regular textured geomembranes tested, the space between the asperities is an important factor.The closer these asperities are, the better the result achieves. For the irregular textured geomembranestested, the nonwoven geotextiles made of monofilaments produce the largest interface shear strength.

关键词： Geotextiles Geomembranes landfills Fiber length Roughness Shear strength Friction angle

One-step multi-compositional oxidation of YSi alloy:Experiments and ab initio computation

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journal of Materials Science & Technology 2023年第27期158卷 253-262页

作者： W.j.Wang j.C.luo l.Chen G.j.Yang State Key laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an jiaotong University Suzhou Institute Suzhou 215123China

YSi alloy is a promising candidate as oxidation resistant coatings for both the bond coat of environmental barrier coatings(EBCs)and anti-ablation coatings at a high temperature of∼1300℃.In this study,a one-step multi-compositional oxidation by rapid heating oxidation mode is proposed to reduce the oxidation rate by 3.6 times compared to conventional slow heating oxidation mode.Results show that preferentially formed Y_(2)O_(3) oxide initiates a multi-step oxidation,produces a cracking and porous oxides,and thereby resulting in a fast oxidation with pesting.The one-step multi-compositional oxidation with a compact and dense Y_(2)Si_(2)O_(7)scale contributes to the much better oxidation resistance for rapid heating oxidation mode of YSi alloy.The stable formation of Y_(2)Si_(2)O_(7)scale is comprehensively understood by the energy barrier,charge density and electronic level based on density functional theory.This study demonstrates a promising application of YSi alloy by rapid heating oxidation mode.

关键词： YSi alloy One-step oxidation Multi-compositional scale Y_(2)Si_(2)O_(7) Energy barrier