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Global kinematics of tectonic plates and subduction zones since the late Paleozoic Era

Geoscience Frontiers 2019年第3期10卷 989-1013页

作者： Alexander Young Nicolas Flament Kayla maloney simon Williams Kara matthews Sabin Zahirovic R.Dietmar müller School of Earth and Environmental Sciences University of Wollongong EarthByte Group School of Geosciences The University of Sydney Sydney Informatics Hub The University of Sydney

Detailed global plate motion models that provide a continuous description of plate boundaries through time are an effective tool for exploring processes both at and below the Earth's surface. A new generation of numerical models of mantle dynamics pre-and post-Pangea timeframes requires global kinematic descriptions with full plate reconstructions extending into the Paleozoic(410 ma). Current plate models that cover Paleozoic times are characterised by large plate speeds and trench migration rates because they assume that lowermost mantle structures are rigid and fixed through time. When used as a surface boundary constraint in geodynamic models, these plate reconstructions do not accurately reproduce the present-day structure of the lowermost mantle. Building upon previous work, we present a global plate motion model with continuously closing plate boundaries ranging from the early Devonian at 410 ma to present *** analyse the model in terms of surface kinematics and predicted lower mantle structure. The magnitude of global plate speeds has been greatly reduced in our reconstruction by modifying the evolution of the synthetic Panthalassa oceanic plates, implementing a Paleozoic reference frame independent of any geodynamic assumptions, and implementing revised models for the Paleozoic evolution of North and South China and the closure of the Rheic Ocean. Paleozoic(410-250 ma) RmS plate speeds are on average ～8 cm/yr, which is comparable to mesozoic-Cenozoic rates of ～6 cm/yr on *** global median values of trench migration trend from higher speeds(～2.5 cm/yr) in the late Devonian to rates closer to 0 cm/yr at the end of the Permian(～250 ma), and during the mesozoic-Cenozoic(250-0 ma) generally cluster tightly around ～1.1 cm/yr. Plate motions are best constrained over the past 130 myr and calculations of global trench convergence rates over this period indicate median rates range between 3.2 cm/yr and 12.4 cm/yr with a present day median rate estimat

关键词： Tectonic reconstruction Paleozoic Plate velocities Subduction zone kinematics Lower mantle structure South China

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Nonlinear shear behavior of rock joints using a linearized implementation of the Barton-Bandis model

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Journal of Rock mechanics and Geotechnical Engineering 2017年第4期9卷 671-682页

作者： simon Heru Prassetyo marte Gutierrez Nick Barton Department of Civil and Environmental Engineering Colorado School of Mines Golden CO 80401 USA Nick Barton and Associates Oslo Norway

Experiments on rock joint behaviors have shown that joint surface roughness is mobilized under shearing,inducing dilation and resulting in nonlinear joint shear strength and shear stress *** displacement *** Barton-Bandis(B-B) joint model provides the most realistic prediction for the nonlinear shear behavior of rock *** B-B model accounts for asperity roughness and strength through the joint roughness coefficient(JRC) and joint wall compressive strength(JCS) ***,many computer codes for rock engineering analysis still use the constant shear strength parameters from the linear mohr-Coulomb(m-C) model,which is only appropriate for smooth and non-dilatant *** limitation prevents fractured rock models from capturing the nonlinearity of joint shear *** bridge the B-B and the m C models,this paper aims to provide a linearized implementation of the B-B model using a tangential technique to obtain the equivalent m-C parameters that can satisfy the nonlinear shear behavior of rock *** equivalent parameters,namely the equivalent peak cohesion,friction angle,and dilation angle,are then converted into their mobilized forms to account for the mobilization and degradation of JRC under *** conversion is done by expressing JRC in the equivalent peak parameters as functions of joint shear displacement using proposed hyperbolic and logarithmic functions at the pre-and post-peak regions of shear displacement,***,the pre-and post-peak joint shear stiffnesses are derived so that a complete shear stress-shear displacement relationship can be *** of the linearized implementation of the B-B model show that the shear stress-shear displacement curves,the dilation behavior,and the shear strength envelopes of rock joints are consistent with available experimental and numerical results.

关键词： Rock joints Joint shear behavior Friction and dilation Barton-Bandis(B-B) model Equivalent mohr-Coulomb(m-C) parameters

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molybdenite Re-Os,titanite and garnet U-Pb dating of the magushan skarn Cu-mo deposit,Xuancheng district,middle-Lower Yangtze River metallogenic Belt

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Geoscience Frontiers 2021年第3期12卷 399-415页

作者： Yue Li Feng Yuan simon m.Jowitt Fangyue Wang Xiangling Li Yufeng Deng Yunyue Wang Taofa Zhou School of Resources and Environmental Engineering Hefei University of TechnologyHefei 23009China Anhui Province Engineering Research Center for mineral Resources and mine Environments Hefei University of TechnologyHefei 23009China Department of Geoscience University of Nevada Las Vegas4505 S.Maryland Pkwy.NV 89154-4010USA

The magushan skarn Cu-mo deposit is a representative example of the skarn mineralization occurring within the Xuancheng ore district of the middle-Lower Yangtze River metallogenic Belt of eastern *** precise age of an ore deposit is important for understanding the timing of mineralization relative to other geological events in a region and to fully place the formation of a mineral deposit within the geological context of other processes that occur within the study ***,we present new molybdenite Re-Os and titanite and andradite garnet U-Pb ages for the magushan deposit and use these data to outline possible approaches for identifying genetic relationships in geologically complex *** spatial and paragenetic relationships between the intrusions,alteration,and mineralization within the study area indicates that the formation of the magushan deposit is genetically associated with the porphyritic ***,this is not always the case,as some areas contain complexly zoned plutons with multiple phases of intrusion or mineralization may be distal from or may not have any clear spatial relationship to a *** means that it may not be possible to determine whether the mineralization formed as a result of single or multiple magmatic/hydrothermal *** such,the approaches presented in this study provide an approach that allows the identification of any geochronological relationships between mineralization and intrusive events in areas more complex than the study *** published zircon U-Pb data for the mineralization-related porphyritic granodiorite in this area yielded an age of 134.2±1.2 ma(mSWD=1.4)whereas the Re-Os dating of molybdenite from the study area yielded an isochron age of 137.7±2.5 ma(mSWD=0.43).The timing of the mineralizing event in the study area was further examined by the dating of magmatic accessory titanite and skarn-related andradite garnet,yielding U-Pb ages of 136.3±2.5 ma(mSWD=3.2)and 135.9±2.7 ma(mSWD=2.

关键词： magushan skarn deposit molybdenite Re-Os dating Titanite U-Pb dating Garnet U-Pb dating Xuancheng ore district middle-Lower Yangtze River metallogenic Belt

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Tritrophic interactions between parasitoids and cereal aphids are mediated by nitrogen fertilizer

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Insect Science 2015年第6期22卷 813-820页

作者： muhammad A. Aqueel Abu-bakar m. Raza Rashad m. Balal muhammad A. Shahid Irfan mustafa muhammad m. Javaid simon R. Leather Division of Biology Imperial College London Silwood Park Campus Ascot SL5 7PY UK University College of Agriculture Department of Biological Sciences University of Sargodha Pakistan Department of Crop and Environment Sciences Harper Adams UniversityShropshire TFIO 8NB UK

Host plant nutritional quality can directly and indirectly affect the third trophic levels. The aphid-parasitoid relationship provides an ideal system to investigate tritrophic interactions （as the parasitoids are completely dependent for their development upon their hosts） and assess the bottom up forces operating at different concentrations of nitrogen applications. The effects of varying nitrogen fertilizer on the performance of Aphidius colemani （V.） reared on Sitobion avenae （E） and Aphidius rhopalosiphi （D.） reared on Rhopalosiphum padi （L.） were measured. Parasitism and percent emergence ofparasitoids were positively affected by nitrogen fertilizer treatments while developmental duration （egg, larval, and pupal stages） was not affected by increasing nitrogen inputs. In males and females of both parasitoid species, adult longevity increased with the increasing nitrogen fertilizer. Hind tibia length and mummy weight of both parasitoid species increased with nitrogen fertilizer concentrations, as a result of larger aphids. This study showed that nitrogen application to the soil can have important consequences for aboveground multitrophic interactions.

关键词： cereal aphid parasitoids nitrogen fertilization tritrophic interactions

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On-the-fly active learning of interpretable Bayesian force fields for atomistic rare events

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npj Computational materials 2020年第1期6卷 1502-1512页

作者： Jonathan Vandermause Steven B.Torrisi simon Batzner Yu Xie Lixin Sun Alexie m.Kolpak Boris Kozinsky Department of Physics Harvard UniversityCambridgeMA 02138USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA Center for Computational Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Department of mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Bosch Research CambridgeMA 02139USA

machine learned force fields typically require manual construction of training sets consisting of thousands of first principles calculations,which can result in low training efficiency and unpredictable errors when applied to structures not represented in the training set of the *** severely limits the practical application of these models in systems with dynamics governed by important rare events,such as chemical reactions and *** present an adaptive Bayesian inference method for automating the training of interpretable,low-dimensional,and multi-element interatomic force fields using structures drawn on the fly from molecular dynamics *** an active learning framework,the internal uncertainty of a Gaussian process regression model is used to decide whether to accept the model prediction or to perform a first principles calculation to augment the training set of the *** method is applied to a range of single-and multi-element systems and shown to achieve a favorable balance of accuracy and computational efficiency,while requiring a minimal amount of ab initio training *** provide a fully opensource implementation of our method,as well as a procedure to map trained models to computationally efficient tabulated force fields.

关键词： fields element typically

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A simultaneous approach for integration of thermal energy storages in industrial processes using multiperiod heat integration

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Energy Storage and Saving 2022年第2期1卷 117-128页

作者： simon möhren Christian Schäfer Jörg meyer Hartmut Krause SWK E2 Institute for Energy Technology and Energy management Hochschule Niederrhein University of Applied ScienceKrefeld47805Germany Institute of Thermal Engineering TU Bergakademie FreibergFreiberg09599Germany

In times of increasing global warming,enormous efforts are required to rapidly reduce greenhouse gas(GHG)*** to the EU’s target of climate neutrality by 2050 and the even more ambitious goal of becoming climate-neutral in Germany by 2045,it is necessary to systematically increase energy efficiency and decarbonize the industrial heat *** methods of heat integration can be used to exploit existing potentials for waste heat utilization and to integrate renewable technologies for heating and *** using a non-stationary,multiperiod approach,additional energy savings can be achieved by integrating a thermal energy storage(TES)that enables heat transportation over *** paper presents a simultaneous approach for thermal energy storage integration into multiperiod heat integration *** approach can be used to minimize energy demand,costs and CO 2 emissions and is demonstrated in two case *** case study 1,it is shown that the presented approach is capable of integrating a TES properly into a simple multiperiod heat integration problem with two *** case study 2,a simplified example from a cosmetics manufactory is *** total utility demand can be reduced by up to 44.3%due to TES integration and the energetic optimal storage size can be determined as 125 m *** savings are strongly dependent on the constellation of heat flows between the periods,on the temperature levels and on the storage *** reductions of energy demand,costs and CO 2 emissions can be achieved with TES being properly integrated into a suitable operating environment.

关键词： multiperiod heat integration Thermal energy storage Waste heat utilization Heat exchanger network Energy efficiency

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Alignment between galaxies and large-scale structure

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 41-58页

作者： A. Faltenbacher Cheng Li simon D. m. White Yi-Peng Jing Shu-De mao Jie Wang max-Planck-Institute for Astrophysics Karl-Schwarzschild-Str. 1 D-85741 Garching Germany mPA/SHAO Joint Center for Astrophysical Cosmology at Shanghai Astronomical Observatory Shanghai 200030 China Jodrell Bank Centre for Astrophysl＇cs Alan Turing Building The University of Manchester Manchester M13 9PL UK Department of Physics Institute of Computational Cosmology University of Durham Science Laboratories South Road Durham DH1 3LE UK

Based on the Sloan Digital Sky Survey DR6 （SDSS） and the ＇millennium Simulation （mS）, we investigate the alignment between galaxies and large-scale structure. For this purpose, we develop two new statistical tools, namely the alignment correlation function and the cos（20）-statistic. The former is a two-dimensional extension of the traditional two-point correlation function and the latter is related to the ellipticity correlation function used for cosmic shear measurements. Both are based on the cross correlation between a sample of galaxies with orientations and a reference sample which represents the large-scale structure. We apply the new statistics to the SDSS galaxy catalog. The alignment correlation function reveals an overabundance of reference galaxies along the major axes of red, luminous （L 〉～L＊） galaxies out to projected separations of 60 h-lmpc. The signal increases with central galaxy luminosity. No alignment signal is detected for blue galaxies. The cos（2θ）-statistic yields very similar results. Starting from a mS semi-analytic galaxy catalog, we assign an orientation to each red, luminous and central galaxy, based on that of the central region of the host halo （with size similar to that of the stellar galaxy）. As an alternative, we use the orientation of the host halo itself. We find a mean projected misalignment between a halo and its central region of -25°. The misalignment decreases slightly with increasing luminosity of the central galaxy. Using the orientations and luminosities of the semi-analytic galaxies, we repeat our alignment analysis on mock surveys of the mS. Agreement with the SDSS results is good if the central orientations are used. Predictions using the halo orientations as proxies for cen- tral galaxy orientations overestimate the observed alignment by more than a factor of 2. Finally, the large volume of the mS allows us to generate a two-dimensional map of the alignment correlation function, which shows the reference galaxy distrib

关键词： dark matter halos clustering-galaxies large-scale structure of Universe- cosmology theory -dark matter

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Expanding plant genome-editing scope by an engineered iSpymacCas9 system that targets A-rich PAm sequences

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Plant Communications 2021年第2期2卷 78-88页

作者： simon Sretenovic Desuo Yin Adam Levav Jeremy D.Selengut Stephen m.mount Yiping Qi Department of Plant Science and Landscape Architecture University of MarylandCollege ParkMD 20742USA Hubei Academy of Agricultural Sciences Wuhan 430064China montgomery Blair High School Silver SpringMD 20901USA Center for Bioinformatics and Computational Biology University of MarylandCollege ParkMD 20742USA Department of Cell Biology and molecular Genetics University of MarylandCollege ParkMD 20742USA Institute for Bioscience and Biotechnology Research University of MarylandRockvilleMD 20850USA

The most popular CRISPR-SpCas9 systemrecognizes canonical NGG protospacer adjacent motifs(PAms).Previously engineered SpCas9 variants,such as Cas9-NG,favor G-rich PAms in genome *** this manuscript,we describe a new plant genome-editing system based on a hybrid iSpymacCas9 platform that allows for targeted mutagenesis,C to T base editing,and A to G base editing at A-rich *** study fills amajor technology gap in the CRISPR-Cas9 system for editing NAAR PAms in plants,which greatly expands the targeting scope of ***,our vector systems are fully compatible with Gateway cloning and will work with all existing single-guide RNA expression systems,facilitating easy adoption of the systems by *** anticipate that more tools,such as prime editing,homology-directed repair,CRISPR interference,and CRISPR activation,will be further developed based on our promising iSpymac-Cas9 platform.

关键词： plant genome editing iSpymacCas9 PAm cytosine base editing adenine base editing

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A visual analytics design for studying rhythm patterns from human daily movement data

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Visual Informatics 2017年第2期1卷 81-91页

作者： Wei Zeng Chi-Wing Fu Stefan müller Arisona simon Schubiger Remo Burkhard Kwan-Liu ma Future Cities Laboratory ETH ZurichSwitzerland The Chinese University of Hong Kong Hong Kong University of Applied Sciences and Arts Northwestern Switzerland FHNW Switzerland University of California-Davis United States

Human’s daily movements exhibit high regularity in a space-time context that typically forms circadian *** the rhythms for human daily movements is of high interest to a variety of parties from urban planners,transportation analysts,to business *** this paper,we present an interactive visual analytics design for understanding and utilizing data collected from tracking human’s *** resulting system identifies and visually presents frequent human movement rhythms to support interactive exploration and analysis of the data over space and *** studies using real-world human movement data,including massive urban public transportation data in Singapore and the mIT reality mining dataset,and interviews with transportation researches were conducted to demonstrate the effectiveness and usefulness of our system.

关键词： movement rhythm Event sequence Visual analytics

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Large Igneous Provinces, Their Giant mafic Dyke Swarms, and Links to metallogeny

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 193-194页

作者： simon m.JOWITT Richard E.ERNST School of Earth Atmosphere and Environment Monash University Department of Geoscience University of Nevada Las Vegas Department of Earth Sciences Carleton University Faculty of Geology and Geography Tomsk State University

Giant mafic dyke swarms are a key component of the feeder system of Large Igneous Provinces（LIPs）,large volume（>0.1 mkm;;frequently above>1 m km;）,mainly mafic（-ultramafic）magmatic events of intraplate affinity.

关键词： Their Giant mafic Dyke Swarms and Links to metallogeny Large Igneous Provinces

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