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Geochemical characteristics and genesis of volcanic and sub-volcanic rocks from porphyrite-type iron deposits in Ningwu metallogenic province,eastern China:Constraints from elements

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Journal of Central South University 2014年第7期21卷 2866-2876页

作者：刘震黄德志刘毓菡古黄玲汪龙 HARTWIG e.Frimmel 戴塔根 School of Geosciences and Info-Physics Central South University Geodynamics and Geomaterials Research Division Institute of Geography and GeologyUniversity of Würzburg

Ningwu porphyrite-type iron deposits are located in Ningwu Mesozoic volcanic basin,which belongs to the middle and lower reaches of the Yangtze River metallogenic *** volcanic rocks can be divided into Longwangshan,Dawangshan,Gushan and Niangniangshan Formations from early to *** these volcanic rocks are rich in alkali,and show the similar patterns in rare earth element(Ree) ***,some differences can be found in the trace elements and Ree *** study of petrology and Ree geochemical characteristics shows that these rocks are derived from the underplating of the lithospheric mantle and are contaminated by crustal materials,undergo AFC process during the magmatic evolution.

关键词： rare earth elements porphyrite-type iron deposit Ningwu volcanic basin mantle-derived magma assimilation fractional crystallization

Influence of age in estimating maximal oxygen uptake

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Journal of Geriatric Cardiology 2016年第2期13卷 126-131页

作者： Christina G de Souza Silva Barry A Franklin Daniel e Forman Claudio Gil S Araujo Heart Institute edson Saad and Medical School Federal University of Rio de Janeiro Rio de Janeiro R J Brazil exercise Medicine Clinic CLINIMEX Rio de Janeiro R J Brazil Preventive Cardiology and Cardiac Rehabilitation William Beaumont Hospital Royal Oak MI United States Section of Geriatric Cardiology University of Pittsburgh Medical Center Geriatrics Research Education and Clinical Center System University of Pittsburgh Pittsburgh PA USA

Objective To assess the influence of age on the error of estimate （ee） of maximal oxygen uptake （VO2max） using sex and population specific-equations in cycle ergometer exercise testing, since estimated VO2 max is associated with a substantial ee, often exceeding 20%, possibly due to intrinsic variability of mechanical efficiency. Methods 1850 adults （68% men）, aged 18 to 91 years, underwent maximal cycle ergometer cardiopulmonary exercise testing. Cardiorespiratory fitness （CRF） was assessed relative to sex and age [younger （18 to 35 years）, middle-aged （36 to 60 years） and older （〉 60 years）]. VO2max [mL.（***）-1] was directly measured by assessment of gas exchange and estimated using sex and population specific-equations. Measured and estimated values of VO2max and related ee were compared among the three age- and sex-specific groups. Results Directly measured VO2max of men and women were 29.5 ± 10.5 mL.（***）-1 and 24.2 ± 9.0 mL.（kg·min） -1 （P 〈 0.01）. ee [mL·（kg·min）-1] and percent errors （%e） for men and women had similar values, 0.5 ± 3.2 and 0.4 ± 2.9 mL·（kg·min）-1, and -0.8 ± 13.1% and -1.7 ± 15.4% （P 〉 0.05）, respectively. ee and %e for each age-group were, respectively, for men： younger = 1.9 ± 4.1 mL·（kg·min）-1 and 3.8 ± 10.5%, middle-aged = 0.6 ± 3.1 mL.（kg·min）-1 and 0.4 ± 10.3%, older = -0.2 ± 2.7 mL·（kg·min） -1 and -4.2 ± 16.6% （P 〈 0.01）; and for women： younger = 1.2 ± 3.1 mL.（***）-1 and 2.7 ±10.0%, middle-aged = 0.7 ± 2.8 mL·（kg·min）-1 and 0.5 ± 11.1%, older = -0.8 ± 2.3 mL-（kg·min）-1 and -9.5 ± 22.4% （P 〈 0.01）. Conclusion VO2max were underestimated in younger age-groups and were overestimated in older age groups. Age significantly influences the magnitude of the ee of VO2max in both men and women and should be considered when CRF is estimated using population specific equations, rather than directly measured.

关键词： Aging Cardiopulmonary exercise testing error of measurement

ReITeRATeD HOMOGeNIZATION OF NONLINeAR MONOTONe OPeRATORS

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Chinese Annals of Mathematics,Series B 2001年第1期22卷 1-12页

作者： J.L.LIONS D.LUKKASSeN L.e.PeRSSON P.WALL CollegedeFrance 3rued＇Ulm75231Pariscedex05France NarvikInstituteofTechnologyandNorutTechnologyLtd. N-8505NarvikNorway DepartmentofMathematics LuleaUniversityofTechnologyS-97187LuleaSweden

In this paper, the authors study reiterated homogenization of nonlinear equations of the form --div(a(x, x/ε x/ε, Duε) = f, where a is periodic in the first two arguments and monotone in the third. It is proved that ue converges weakly in W1,P(Ω) (and even in some multiscale sense), as ε→ 0 to the solution uo of a limit problem. Moreover, an explicit expression for the limit problem is given. The main results were also stated in [15]. This article presents the complete proofs of these results.

关键词： Homogenization Nonlinear monotone operators Nonlinear equation

Chemically intuited,large-scale screening of MOFs by machine learning techniques

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npj Computational Materials 2017年第1期3卷 123-129页

作者： Giorgos Borboudakis Taxiarchis Stergiannakos Maria Frysali emmanuel Klontzas Ioannis Tsamardinos George e.Froudakis Department of Computer Science University of CreteVoutes CampusGR-70013 HeraklionCreteGreece Gnosis Data Analysis PC Palaiokapa 6571305 HeraklionGreece Department of Chemistry University of CreteVoutes CampusGR-70013 HeraklionCreteGreece School of Computing and engineering University of HuddersfieldQueensgateHuddersfieldHD13DHUK

A novel computational methodology for large-scale screening of MOFs is applied to gas storage with the use of machine learning *** approach is a promising trade-off between the accuracy of ab initio methods and the speed of classical approaches,strategically combined with chemical *** results demonstrate that the chemical properties of MOFs are indeed predictable(stochastically,not deterministically)using machine learning methods and automated analysis protocols,with the accuracy of predictions increasing with sample *** initial results indicate that this methodology is promising to apply not only to gas storage in MOFs but in many other material science projects.

关键词： apply stochastic learning

extensional collapse of the Gondwana orogen: evidence from Cambrian mafic magmatism in the Trivandrum Block, southern India

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Geoscience Frontiers 2019年第1期10卷 263-284页

作者： Qiong-Yan Yang Sohini Ganguly e.Shaji Yunpeng Dong V.Nanda-Kumar School of earth Science and Resources China University of Geosciences Department of earth Science Goa University Department of Geology University of Kerala State Key Laboratory of Continental Dynamics Department of Geology Northwest University National Center for earth Science Studies Akkulam Trivandrum India

The assembly of Late Neoproterozoice Cambrian supercontinent Gondwana involved prolonged subduction and accretion generating arc magmatic and accretionary complexes, culminating in collision and formation of high grade metamorphic orogens. Here we report evidence for mafic magmatism associated with post-collisional extension from a suite of gabbroic rocks in the Trivandrum Block of southern Indian Gondwana fragment. Our petrological and geochemical data on these gabbroic suite show that they are analogous to high Fe tholeiitic basalts with evolution of the parental melts dominantly controlled by fractional crystallization. They display enrichment of LILe and LRee and depletion of HFSe with negative anomalies at Zre Hf and Ti corresponding to subduction zone magmatic regime. The tectonic affinity of the gabbros coupled with their geochemical features endorse a heterogeneous mantle source with collective melt contributions from sub-slab asthenospheric mantle upwelling through slab break-off and arc-related metasomatized mantle wedge, with magma emplacement in subduction to post-collisional intraplate settings. The high Nb contents and positive Nbe Ta anomalies of the rocks are attributed to inflow of asthenospheric melts containing ancient recycled subducted slab components and/or fusion of subducted slab materials owing to upwelling of hot asthenosphere. Zircon grains from the gabbros show magmatic crystallization texture with low U and Pb content. The LA-ICPMS analyses show ^(206) Pb/^(238) U mean ages in the range of 507-494 Ma suggesting Cambrian mafic magmatism. The post-collisional mafic magmatism identified in our study provides new insights into mantle dynamics during the waning stage of the birth of a supercontinent.

关键词： Mafic dykes Geochemistry Zircon Ue Pb geochronology Post-collisional extension Gondwana supercontinent

Administration of granulocyte colony stimulating factor after liver transplantation leads to an increased incidence and severity of ischemic biliary lesions in the rat model

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World Journal of Gastroenterology 2006年第31期12卷 5021-5027页

作者： Olaf Dirsch Haidong Chi Yuan Ji Yan Li Gu Christoph e Broelsch Uta Dahmen Institute of Pathology University Hospital Cologne Joseph-Stelzmann Strasse 9 D-50931 Cologne Germany Department of General Visceral and Transplantation Surgery University Hospital Essen Hufelandstrasse 55 D-45122 Essen Germany

AIM： Recently it has been reported that granulocyte colony stimulating factor （G-CSF） can induce hypercoagulability in healthy bone marrow donors. It is conceivable that the induction of a prothrombotic state in a recipient of an organ graft with already impaired perfusion might cause further deterioration in the transplanted organ. This study evaluated whether G-CSF treatment worsens liver perfusion following liver transplantation in the rat model. MeTHODS： A non-arterialized rat liver transplantation model was employed to evaluate the effect of G-CSF treatment on the liver in a syngeneic and allogeneic strain combination. Study outcomes included survival time and liver damage as investigated by liver enzymes and liver histology. Observation times were 1 d, 1 wk and 12 wk. ReSULTS： Rats treated with G-CSF had increased incidence and severity of biliary damage following liver transplantation. In these animals, hepatocellular necrosis was accentuated in the centrilobular region. These lesions are indicative of impaired perfusion in G-CSF treated animals. CONCLUSION： G-CSF should be used with caution in recipients of liver transplantation, as treatment might enhance preexisting, undetected perfusion problems and ultimately lead to ischemia induced biliary complications .

关键词： Granulocyte colony stimulating factor Ischemic biliary lesions Hypercoagulability Liver transplantation

The effect of substrate grain size on burrowing ability and distribution characteristics of Perinereis aibuhitensis

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Acta Oceanologica Sinica 2019年第12期38卷 52-58页

作者： Tao Sun Chun’e Liu Xingzuo Li Dongzhengyang An Hairui Yu Zheng Ma Feng Liu Yantai Research Institute China Agricultural UniversityYantai 264670China School of Public Health Harvard UniversityCambridge 02138USA College of Biological and Agricultural engineering Weifang UniversityWeifang 261061China Shandong Dongrun Instrument Sci-Tech Co. Ltd.Yantai 264003China

Perinereis aibuhitensis(Grube, 1878) lives in marine sediments of estuary or shoal areas, where substrate has some crucial environmental factors affecting its burrowing and distribution. In order to provide basic data for the habitat selection and suitability evaluations of the artificial aquaculture of P. aibuhitensis, this paper conducted a quantified analysis of its burrowing ability and explored its behavioral preferences in different substrates,including mud(e sand(125–250 μm), medium sand(250–500 μm), coarse sand(500–2 000 μm), gravel(2 000–4 000 μm) and ceramsite(4 000–8 000 μm). The research results revealed that substrate grain size significantly affected the burrowing time, burrowing rate, burrowing depth and distribution rate(Peover, P. aibuhitensis demonstrated preferential selections relating to substrate grain sizes, had higher burrowing ability in ceramsite, mud and fine sand compared with other substrates. The strongest burrowing ability and the highest distribution rate were observed in ceramsite. The study indicated that P. aibuhitensis was sensitive to substrate grain size, which also had an impact on its burrowing process and population *** the natural sea, substrates mainly composed of mud and fine sand are fit for aquaculture and stock enhancement. Based on behavioral preferences and ecological rehabilitation function of P. aibuhitensis, this paper proposes a symbiotic system of marine animals and halophytes, and constructs an ecosystem model of"Marine fish-Halophytes-Perinereis aibuhitensis" with P. aibuhitensis as the link.

关键词： Perinereis aibuhitensis substrate grain size burrowing ability distribution characteristics

Physical Properties of Ⅲ-Antiminodes—a First Principles Study

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Communications in Theoretical Physics 2009年第9期52卷 527-533页

作者： Rashid Ahmed Fazal-e-Aleem S.Javad Hashemifar Haris Rashid H.Akbarzadeh Centre for High energy Physics University of the Punjab Department of Physics Isfahan University of Technology

A comprehensive first principles study of III-Antimonide binary compounds is hardly found in literature. We report a broad study of structural and electronic properties of boron antimonide （BSb）, aluminium antimonide （AlSb）, gallium antimonide （GaSb） and indium antimonide （InSb） in zineblende phase based on density functional theory （DFT）. Our calculations are based on Full-PotentiM Lineaxized Augmented Plane wave plus local orbitals （FP- L（APWq-lo）） method. Different forms of exchange-correlation energy functional and corresponding potential are employed for structural and electronic properties. Our computed results for lattice parameters, bulk moduli, their pressure derivatives, and cohesive energy are consistent with the available experimental data. Boron antimonide is found to be the hardest compound of this group. For band structure calculations, in addition to LDA and GGA, we used GGA-eV, an approximation employed by engel and Vosko. The band gap results with GGA-eV are of significant improvement over the earlier work.

关键词： III-antimonides DFT FPLAPW exchange correlation functional structural properties of solids band structure of crystalline solids

Sea ice concentration over the Antarctic Ocean from satellite pulse altimetry

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Science China earth Sciences 2011年第1期54卷 113-118页

作者： YANG YuanDe e DongChen WANG ,HaiHong CHAO DingBo HWANG CheinWay LI Fei AI SongTao Chinese Antarctic Center of Surveying and Mapping Wuhan University Wuhan 430079 China School of Geodesy and Geomatics Wuhan University Wuhan 430079 China Key Laboratory of Surveying and Mapping Technology on Island and Reef State Bureau of Surveying and Mapping Qingdao 266510 China Department of Civil engineering 'National' Chiao Tung University Hsinchu Taiwan China

Sea ice concentration (SIC) is an important parameter in characterizing sea ice. Limited by the environment and the spatial extent of observation, it is difficult for field work to meet the needs of a large-scale SIC study. However, with its many advantages, such as the ability to make large-scale, high-resolution and long-duration observations, the altimeter can be used to determine SIC on a large scale. Using the correspondence between the satellite pulse altimeter waveform and reflector property, waveform classification is employed. Moreover, this paper develops an algorithm to obtain the SIC from altimeter waveforms. In an actual computation, Pyrz Bay in the Antarctic is taken as an experimental region, and one-year and seasonal SICs are derived from eRS-1/GM waveforms over this study area. Furthermore, altimetric SICs are compared with those of SSMR SSM/I. The results show that the spatial distribution and the regions of maximum SIC determined employing these two methods are consistent. This demonstrates that altimeter data can be used to monitor sea ice.

关键词： sea ice concentration Antarctic altimeter waveform SSMR SSM/I eRS-1/GM