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Generation and preservation of continental crust in the Grenville Orogeny

Geoscience Frontiers 2015年第3期6卷 357-372页

作者： christopher j.Spencer Peter A.Cawood chris j.hawkesworth Anthony R.Prave Nick M.W.Roberts Matthew S.A.Horstwood Martin j.Whitehouse EIMF Department of Earth and Environmental Sciences University of St Andrews NERC Isotope Geosciences Laboratory British Geological Survey Swedish Museum of Natural History and Nordic Center for Earth Evolution(NordCEE) Edinburgh Ion Microprobe Facility University of Edinburgh

Detrital zircons from modern sediments display an episodic temporal distribution of U-Pb crystallization ages forming a series of ＇peaks＇ and ＇troughs＇. The peaks are interpreted to represent either periods of enhanced generation of granitic magma perhaps associated with mantle overturn and superplume events, or preferential preservation of continental crust during global collisional orogenesis. The close association of those peaks with the assembly of supercontinents implies a causal relationship between collisional orogenesis and the presence of zircon age peaks. Here these two end-member models （episodic periodicity of increased magmatism versus selective preservation during collisional orogenesis） are assessed using U-Pb, Hf, and 0 analysis of detrital zircons from sedimentary successions deposited during the - 1.3-1.1 Ga accretionary, -1.1-0.9 Ga collisional, and 〈 0.9 Ga extensional collapse phases of the Grenville orogenic cycle in Labrador and Scotland. The pre-collisional, accretionary stage provides a baseline of continental crust present prior to orogenesis and is dominated by Archean and Paleoproterozoic age peaks associated with pre-1300 Ma Laurentian geology. Strata deposited during the Grenville Orogeny display similar Archean and Paleoproterozoic detrital populations along with a series of broad muted peaks from - 1500 to 1100 Ma. However, post-collisional sedimentary successions display a dominant age peak between 1085 and 985 Ma, similar to that observed in modern North American river sediments. Zircons within the post-orogenic sedimentary successions have progressively lower EHf and higher -lSO values from - 1800 to - 1200 Ma whereupon they have higher EHf and -3180 within the dominant 1085-985 Ma age peak. Furthermore, the Lu-Hf isotopic profile of the Grenville-related age peak is consistent with significant assimilation and contamination by older crustal material, The timing of this dominant age peak coincides with the peak of metamorphism and

关键词： Zircon Continental crust Grenville Orogeny Crustal preservation

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The generation and evolution of the Archean continental crust:The granitoid story in southeastern Brazil

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Geoscience Frontiers 2022年第4期13卷 144-164页

作者： Rodrigo S.Marimon chris j.hawkesworth Elton L.Dantas Rudolph A.j.Trouw Wilson Teixeira Peter C.Hackspacher Allen Fetter Ciro A.Ávila Silvia Volante Atlas V.Corrêa Neto Everton M.Bongiolo Rodrigo Vinagre Maurício Simon Depto.de Geologia IGEOUniversidade Federal do Rio de JaneiroUFRJRio de JaneiroRJBrazil School of Earth Sciences University of BristolBristolUnited Kingdom Instituto de Geociências Universidade de BrasíliaUnBBrasíliaDFBrazil Instituto de Geociências Universidade de São PauloUSPSão PauloSPBrazil Instituto de Geociências e Ciências Exatas Universidade Estadual PaulistaRio ClaroSPBrazil Institute of Geology Mineralogy and GeophysicsRuhr-Universität BochumUniversitätsstraße 15044801 BochumGermany ISOTOPIA Lab School of EarthAtmosphere and EnvironmentMonash UniversityWellington RdClaytonVIC 3800Australia Programa de Pós-Graduação em Geociências IGUniversidade Federal do Rio Grande do SulUFRGSPorto AlegreRSBrazil

The Archean Eon was a time of geodynamic *** evidence of these transitions come from igneous/metaigneous rocks,which dominate cratonic segments *** data for granitoids from an Archean basement inlier related to the Southern S?o Francisco Craton(SSFC),are integrated with geochronological,isotopic and geochemical data on Archean granitoids from the *** rocks are divided into three main geochemical groups with different ages:(1)TTG(3.02–2.77 Ga);(2)mediumto high-K granitoids(2.85–2.72 Ga);and(3)A-type granites(2.7–2.6 Ga).The juvenile to chondritic(Hf-Nd isotopes)TTG were divided into two sub-groups,TTG 1(low-HREE)and 2(high-HREE),derived from partial melting of metamafic rocks similar to those from adjacent greenstone *** compositional diversity within the TTG is attributed to different pressures during partial melting,supported by a positive correlation of Dy/Yb and Sr/Zr,and batch melting *** proposed TTG sources are geochemically similar to basaltic rocks from modern island-arcs,indicating the presence of subduction processes concomitant with TTG ***~2.85 Ga to 2.70 Ga,the dominant rocks were K-rich *** are modeled as crustal melts of TTG,during regional metamorphism indicative of crustal *** compositional diversity is linked to:(i)differences in source composition;(ii)distinct melt fractions during partial melting;and(iii)different residual mineralogies reflecting varying P–T ***-collisional(~2.7–2.6 Ga)A-type granites reflect rifting in that they were closely followed by extension-related dyke swarms,and they are interpreted as differentiation or partial melting products of magmas derived from subduction-modified *** sequence of granitoid emplacement indicates subduction-related magmatism was followed by crustal thickening,regional metamorphism and crustal melting,and post-collisional extension,similar to that seen in younger Wilson *** is compelling evide

关键词： Granitoid petrogenesis Archean geodynamics Crustal evolution TTGs A-types Batch melting calculations

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Attitude control of multi-spacecraft systems on SO(3)with stochastic links failure

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Chinese journal of Aeronautics 2024年第3期37卷 320-331页

作者： KANG Zeyu SHEN Qiang WU Shufan chris j.DAMAREN MU Zhongcheng School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Institute for Aerospace Studies University of TorontoTorontoOntario M3H 5T6Canada

In this paper,for Multi-Spacecraft System(MSS)with a directed communication topology link and a static virtual leader,a controller is proposed to realize attitude consensus and attitude stabilization with stochastic links failure and actuator ***,an MSS attitude error model suitable for a directed topology link and with a static virtual leader based on SO(3)is derived,which considers that the attitude error on SO(3)cannot be defined based on algebraic ***,we design a controller to realize the MSS on SO(3)with attitude consensus and attitude stabilization under stochastic links failure and actuator ***,the simulation results of a multi-spacecraft system with stochastic links failure and a static virtual leader spacecraft are demonstrated to illustrate the efficiency of the attitude controller.

关键词： Multi-spacecraft systems Attitude consensus Attitude stabilization Stochastic links failure Super-martingale convergence

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Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma chris j.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

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Eco-evolutionary evidence for the global diversity pattern of Cycas(Cycadaceae)

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journal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： jian Liu Anders jLindstrom Yiqing Gong Shanshan Dong Yusheng(chris)Liu Shouzhou Zhang Xun Gong CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Global Biodiversity Conservancy 144/124 Moo3Soi Bua ThongBangsalaeSattahipChonburi 20250Thailand Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004China Department of Earth and Environmental Sciences Indiana University-IndianapolisIndianapolisIN 46202USA

The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ***,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately *** are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the ***,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely ***,using 1,843 nuclear genes from a nearly complete sampling,we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas,the largest genus within *** then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages,diversification rates,contemporary environment,and conservatism to ancestral niches in shaping the i-LDG *** found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental *** regions have distinctively contributed to the formation of i-LDG for Cycas,with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as ***,water-related climate variables,specifically precipitation seasonality and potential evapotranspiration,were identified as paramount factors constraining Cycas species richness in the rainforest biome near the ***,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity *** study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

关键词： cycads latitudinal diversity gradient niche conservatism spatiotemporal diversification species richness

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Experimental and analytical investigation on friction resistance force between buried coated pressurized steel pipes and soil

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 615-629页

作者： Shaurav ALAM Tanvir MANZUR john MATTHEWS chris BARTLETT Erez ALLOUCHE Brent KEIL john KRAFT Department of Civil Engineering and Construction Engineering Technology Louisiana Tech UniversityRustonLA 71270USA Department of Civil Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh Georgia Tech Research Institute AtlantaGA 30332USA Stantec Inc. Edmonton T5J0K4Canada North West Pipe Company VancouverWA 98684USA

This paper presents an analytical approach for estimating frictional resistance to pipe movement at soil and external pipe surface of buried coated pressurized steel pipes relative to the internal thrust *** proposed analytical method was developed based on 36 experiments,which involved three coating types(cement mortar(CM),polyurethane type-I(PT-I),prefabricated plastic tape(PPT))on pipes’surfaces,three different soils(pea-gravel(PG),sand(S),silty-clay(SC)),and four simulated over burden depths above the pipe’s *** showed frictional resistance decreased with increasing over burden depth above the pipe’s *** degree of frictional resistance at the pipe-soil interface was found to be in the order of PG>SC>S for all coating variations and overburden *** coated pipe buried in all three types of soil produced significantly higher frictional resistance as compared to other coating *** on experimental data,the developed analytical introduced a dimensionless factor“Z”,which included effects of types of coatings,soil,and overburden depths for simplified rapid *** showed that the method provided a better prediction of frictional resistance forces,in comparison to previous analytical methods,which were barely close in predicting friction resistance for different coating variations,soil types,and overburden *** resistance force values reported herein could be considered conservative.

关键词： friction resistance force thrust force coated pressurized steel pipe soil type overburden depth

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Comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

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journal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.Stephen chris R.Burke jennie E.Pryce Nicole M.Steele Peter R.Amer Susanne Meier Claire V.C.Phyn Dorian j.Garrick DairyNZ Ltd 605 Ruakura RoadHamilton 3240New Zealand AL Rae Centre for Genetics and Breeding-Massey University RuakuraHamilton 3214New Zealand Agriculture Victoria Research AgriBioCentre for AgriBioscienceBundooraVictoria 3083Australia School of Applied Systems Biology La Trobe UniversityBundooraVictoria 3083Australia AbacusBio DunedinNew Zealand

Background Many phenotypes in animal breeding are derived from incomplete measures,especially if they are challenging or expensive to measure *** include time-dependent traits such as reproductive status,or *** measures for these traits result in phenotypes that are subject to left-,interval-and rightcensoring,where phenotypes are only known to fall below an upper bound,between a lower and upper bound,or above a lower bound *** we compare three methods for deriving phenotypes from incomplete data using age at first elevation(>1 ng/mL)in blood plasma progesterone(AGEP4),which generally coincides with onset of puberty,as an example *** We produced AGEP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×jersey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New *** used these actual data to simulate 7 different visit scenarios,increasing the extent of censoring by disregarding data from one or two of the three *** methods for deriving phenotypes from these data were explored:1)ordinal categorical variables which were analysed using categorical threshold analysis;2)continuous variables,with a penalty of 31 d assigned to right-censored phenotypes;and 3)continuous variables,sampled from within a lower and upper bound using a data augmentation *** Credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was *** sires with at least 5 daughters,the correlations between estimated breeding values(EBVs)from our three-visit scenario and each reduced data scenario varied by method,ranging from 0.65 to *** estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring *** Our results indicate that using

关键词： Cattle Gibbs sampler Markov-chain Monte Carlo(MCMC) Puberty

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Individual consistency in spatiotemporal characteristics of migratory Whimbrels in the East Asian-Australasian Flyway

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Avian Research 2024年第3期15卷 308-315页

作者： Siwei An Fenliang Kuang Wei Wu chris j.Hassell jonathan T.Coleman Zijing Gao Xuena Sun Yue Yuan Grace Maglio Kar-Sin K.Leung Xuesong Feng Zhijun Ma Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Coastal Ecosystems Research Station of the Yangtze River EstuaryInstitute of Biodiversity ScienceSchool of Life SciencesFudan UniversityShanghai200433China School of Chemistry and Environment Yunnan Minzu UniversityKunming650504China Shanghai Chongming Dongtan Nature Reserve Administration Center ChongmingShanghai202183China Global Flyway Network PO Box 3089BroomeWA 6725Australia Australasian Wader Studies Group BroomeWA6725Australia Queensland Wader Study Group Shailer ParkQLD4128Australia Hong Kong Waterbirds Ringing Group Hong Kong999077China

Many migratory birds exhibit interannual consistency in migration schedules,routes and stopover *** the interannual consistency in spatiotemporal characteristics helps understand the maintenance of migration and enables the implementation of targeted conservation *** tracked the migration of Whimbrel(Numenius phaeopus)in the East Asian-Australasian Flyway and collected spatiotemporal data from individuals that were tracked for at least two *** non-parametric tests were used to compare the interannual variations in the dates of departure from and arrival at breeding/nonbreeding sites,and the inter-annual variation in the longitudes when the same individual across the same *** exhibited a high degree of consistency in the use of breeding,nonbreeding,and stopover sites between *** variation of arrival dates at nonbreeding sites was significantly larger than that of the departure dates from nonbreeding and breeding *** used stopover sites by the same individuals in multiple years were concentrated in the Yellow Sea coast during northward migration,but were more widespread during southward *** stopover duration at repeatedly used sites was significantly longer than that at sites used only *** flying across the Yellow Sea,Whimbrels breeding in Sakha(Yakutia)exhibited the highest consistency in migration routes in both autumn and ***,the consistency in migration routes of Yakutia breeding birds was generally higher than that of birds breeding in *** results suggest that the northward migration schedule of the Whimbrels is mainly controlled by endogenous factors,while the southward migration schedule is less affected by endogenous *** repeated use of stopover sites in the Yellow Sea coast suggests this region is important for the migration of Whimbrel,and thus has high conservation value.

关键词： Consistency Migration route Migration timing Shorebird

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Rates of generation and growth of the continental crust

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Geoscience Frontiers 2019年第1期10卷 165-173页

作者： chris hawkesworth Peter A.Cawood Bruno Dhuime School of Earth Sciences University of Bristol School of Earth Atmosphere and Environment Monash University CNRS-UMR 5243 Géosciences Montpellier Université de Montpellier

Models for when and how the continental crust was formed are constrained by estimates in the rates o crustal growth. The record of events preserved in the continental crust is heterogeneous in time with distinctive peaks and troughs of ages for igneous crystallisation, metamorphism, continental margin and mineralisation. For the most part these are global signatures, and the peaks of ages tend to b associated with periods of increased reworking of pre-existing crust, reflected in the Hf isotope ratios o zircons and their elevated oxygen isotope ratios. Increased crustal reworking is attributed to periods o crustal thickening associated with compressional tectonics and the development of supercontinents Magma types similar to those from recent within-plate and subduction related settings appear to hav been generated in different areas at broadly similar times before ~3.0 Ga. It can be difficult to put th results of such detailed case studies into a more global context, but one approach is to consider when plate tectonics became the dominant mechanism involved in the generation of juvenile continental crust The development of crustal growth models for the continental crust are discussed, and a number o models based on different data sets indicate that 65%-70% of the present volume of the continental crus was generated by 3 Ga. Such estimates may represent minimum values, but since ~3 Ga there has been reduction in the rates of growth of the continental crust. This reduction is linked to an increase in th rates at which continental crust is recycled back into the mantle, and not to a reduction in the rates a which continental crust was generated. Plate tectonics results in both the generation of new crust and it destruction along destructive plate margins. Thus, the reduction in the rate of continental crustal growth at ~3 Ga is taken to reflect the period in which plate tectonics became the dominant mechanism b which new continental crust was generated.

关键词： Continental crust growth curves Rates of crustal growth Tectonics

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Hepatic vein reconstruction during hepatectomy:A feasible and underused technique

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 421-427页

作者： Manish Ahuja Kunal joshi chris Coldham Paulo Muiesan Bobby Dasari Manuel Abradelo Ravi Marudanayagam Darius Mirza john Isaac David Bartlett Nikolaos A Chatzizacharias Robert P Sutcliffe Keith j Roberts Department of HPB and Liver Transplant Surgery University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Immunology and Immunotherapy University of BirminghamBirminghamUK

Complete surgical resection(R0)of liver tumors,primary or metastatic,remains the main objective in management of primary and metastatic liver tumors[1].Tumors invading to the proximity of the hepatic venous outflow pose a peculiar challenge to achieve R0 resections,because this location may render a tumor *** median survival of patients with liver tumor without surgery is less than 12 months[2].Even with surgery,post-hepatectomy liver failure and subsequently increased mortality are the main problems associated with complex resection[3].Moreover,when the vein is affected,vein resection and subsequent reconstruction are *** resection is a standard practice in liver resection and transplantation[4],for example,hepatic vein reconstruction during a living-donor liver transplant,porto-mesenteric axis reconstruction during resection of advanced pancreatic cancer and caval reconstruction during resection of retroperitoneal ***,novel techniques like total hepatic vascular exclusion(HVE)[5],veno-venous bypass[6]and ex vivo hepatic resection[7,8]have facilitated curative resections of tumors close to one or more major hepatic veins.

关键词： hepatectomy surgery mortality

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