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Summary of a Life in Observational Ultraviolet/Optical Astronomy

Research in Astronomy and Astrophysics 2024年第1期24卷 1-43页

作者： donald G.York Department of Astronomy and Astrophysics The University of Chicago5801 South Ellis Ave.Chicago 60637ILUSA

I reminisce on my early life in Section 1;on my education in Sections 2 and 3;on the years at Princeton as a research astronomer in Section 4;on the years on the faculty at Chicago in Section 5;on research on Diffuse Interstellar Bands(DIBs) in Section 6;on construction of the 3.5 m telescope at Apache Point Observatory(APO)in Section 7;on work on the Sloan Digital Sky Survey(SDSS) in Section 8;on work in public education in Chicago in Section 9;and on my travels in Section 10. my main science research is of an observational nature,concerning Galactic and intergalactic interstellar gas. Highlights for me included my work on the orbiting telescope Copernicus, including the discovery of interstellar deuterium;early observations of absorption associated with fivetimes ionized oxygen;and discoveries concerning the phases of gas in the local interstellar medium, based on previously unobservable interstellar UV spectral lines. With other instruments and collaborations, I extended interstellar UV studies to the intergalactic cool gas using quasi-stellar object QSO absorption lines redshifted to the optical part of the spectrum;provided a better definition of the emission and morphological character of the source of absorption lines in QSO spectra;and pursued the identification of the unidentified DIBs. For several of these topics, extensive collaborations with many scientists were essential over many years. The conclusions developed slowly, as I moved from being a graduate student at Chicago, to a research scientist position at Princeton and then to a faculty position at Chicago. At each stage of life, I was exposed to new technologies adaptable to my science and to subsequent projects. From high school days, I encountered several management opportunities which were formative. I have been extremely fortunate both in scientific mentors I had and in experimental opportunities I encountered.

关键词： Interstellar medium(ISm) Nebulae (galaxies:)quasars:absorption lines ultraviolet:stars

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Tanaka Formula and Local Time for a Class of Interacting Branching measure-valued Diffusions

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Acta mathematica Sinica,English Series 2024年第4期40卷 1059-1098页

作者： donald A.DAWSON jean VAILLANCOURT Hao WANG School of mathematics and Statistics Carleton UniversityOttawaCanada Department of Decision Sciences HECMontrealCanada Department of mathematics University of OregonEugeneUSA

We construct superprocesses with dependent spatial motion(SDSms)in Euclidean spaces R^(d)with d≥1 and show that,even when they start at some unbounded initial positive Radon measure such as Lebesgue measure on R^(d),... 详细信息

关键词： measure-valued diffusions stochastic partial differential equations superprocesses branching processes local time Tanaka formula

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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Calibration of the DEm sliding friction and rolling friction parameters of a cohesionless bulk material

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Particuology 2024年第9期92卷 126-139页

作者： jonatan marín Pérez Tugrul Comlekci Yevgen Gorash donald macKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEm)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEm simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEm parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction Particle shape

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Unimolecular Reactions of E-Glycolaldehyde Oxide and Its Reactions with One and Two Water molecules

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Research 2024年第1期2023卷 809-824页

作者： Yan Sun Bo Long donald G.Truhlar Department of Physics Guizhou UniversityGuiyang 550025China College of materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Chemistry Chemical Theory Centerand Supercomputing InstituteUniversity of MinnesotaMinneapolisMN 55455-0431USA

The kinetics of Criegee intermediates are important for atmospheric ***,the quantitative kinetics of Criegee intermediates are still very limited,especially for those with hydroxy ***,we calculate rate constants for the unimolecular reaction of E-glycolaldehyde oxide[E-hydroxyethanal oxide,E-(CH_(2)OH)CHOO],for its reactions with H_(2)O and(H_(2)O)_(2),and for the reaction of the E-(CH_(2)OH)CHOO…H_(2)O complex with H_(2)*** the highest level of electronic structure,we use W3X-L//CCSD(T)-F12a/cc-pVDZ-F12 for the unimolecular reaction and the reaction with water and W3X-L//DF-CCSD(T)-F12b/jun-cc-pVDZ for the reaction with 2 water *** the dynamics,we use a dual-level strategy that combines conventional transition state theory with the highest level of electronic structure and multistructural canonical variational transition state theory with small-curvature tunneling with a validated density functional for the electronic structure.

关键词： structure kinetics molecular

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Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making approach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.P.SALAImANImAGUDAm j.jAYAPRAKASH Department of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have provided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a complex *** paper presents alternatives and criteria for selection of digital fabrication techniques by adopting the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)printing,shotcrete,smart dynamic casting,material intrusion,mesh molding,injection concrete 3D printing,and thin forming *** criteria include formwork utilization,reinforcement incorporation,geometrical complexity,material enhancement,assembly complexity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorporation,build area,and geometrical complexity play a pivotal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D printing emerged as the best performer,however the shotcrete and mesh molding techniques in the second and third positions.

关键词： digital fabrication multicriteria decision-making concrete 3D printing

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Thermomechanical analysis of long-term global modal and local deformation measurements of the Kishwaukee Bridge using the bootstrap

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Earthquake Engineering and Engineering Vibration 2004年第1期3卷 107-115页

作者： George m.lloyd ming L.Wang Department of Civil and material Engineering University of Illinois at Chicago

In this paper we present a comparative analysis of global frequency and local deformation data for a large concrete bridge. The asymptotic probability distributions of the central statistics are presented, and compared with empirical bootstrap estimates. Bootstrapped distributions are calculated from reference data obtained during 1999–2000 and used to develop change-point alarm criteria for the structure, using reasonable sensitivity measures developed from FEm simulations and structural analysis. The implications of the frequency data are discussed in conjunction with the strain and displacement measurements in order to discern if the load carrying capacity of the bridge has been affected. The critical need for more advanced temperature compensation models for large structures continually in thermal disequilibrium is discussed.

关键词： thermomechanical effects bootstrap methods local & global monitoring long term measurement concrete bridge

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Ripening and rot:How ripening processes influence disease susceptibility in fleshy fruits

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journal of Integrative Plant Biology 2024年第9期66卷 1831-1863页

作者： Shan Li Yu Zhao Pan Wu donald Grierson Lei Gao State Key Laboratory of Plant Diversity and Specialty Crops Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China Plant and Crop Sciences Division School of BiosciencesUniversity of NottinghamSutton Bonington CampusLoughboroughLE125RDUK Hubei Hongshan Laboratory Wuhan 430070China

Fleshy fruits become more susceptible to pathogen infection when they ripen;for example,changes in cell wall properties related to softening make it easier for pathogens to infect *** need for high-quality fruit has driven extensive research on improving pathogen resistance in important fruit crops such as tomato(Solanum lycopersicum).In this review,we summarize current progress in understanding how changes in fruit properties during ripening affect infection by *** changes affect physical barriers that limit pathogen entry,such as the fruit epidermis and its cuticle,along with other defenses that limit pathogen growth,such as preformed and induced defense *** plant immune system also protects ripening fruit by recognizing pathogens and initiating defense responses involving reactive oxygen species production,mitogen-activated protein kinase signaling cascades,and jasmonic acid,salicylic acid,ethylene,and abscisic acid *** phytohormones regulate an intricate web of transcription factors(TFs)that activate resistance mechanisms,including the expression of pathogenesis-related *** tomato,ripening regulators,such as RIPENING INHIBITOR and NON_RIPENING,not only regulate ripening but also influence fruit defenses against ***,members of the ETHYLENE RESPONSE FACTOR(ERF)family play pivotal and distinct roles in ripening and defense,with different members being regulated by different *** also discuss the interaction of ripening-related and defense-related TFs with the mediator transcription *** the ripening processes in climacteric and non-climacteric fruits share many similarities,these processes have broad applications across fruiting *** research on the individual contributions of ERFs and other TFs will inform efforts to diminish disease susceptibility in ripe fruit,satisfy the growing demand for high-quality fruit and decrease food waste and related economic losses.

关键词： fleshy fruit pathogen phytohormones ripening transcription factors

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Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEmATI m.SEFID A.KARImIPOUR A.j.CHAmKHA Faculty of mechanical Engineering Yazd UniversityYazd ***Iran Department of mechanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(mF)is very vital due to its existence in various sectors of industry and *** present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection *** temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is *** formulation of the problem is derived with the lattice Boltzmann method(LBm)by code writing via the FORTRAN *** variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed mF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are *** findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates *** is the lowest cooling performance index and mF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research.

关键词： thermal performance analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity

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Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECH 2024年第2期5卷 239-246页

作者： j.m.Lukasiewicz C.C.m.van de Wiel L.A.P.Lotz m.j.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

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