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Zircon within chromitite requires revision of the tectonic history of the Eoarchean Itsaq Gneiss complex,Greenland

Geoscience Frontiers 2023年第6期14卷 273-285页

作者： Hikaru Sawada Tomoaki Morishita Adrien Vezinet Richard Stern Kenichiro Tani Ikuya Nishio Kanta Takahashi d.graham pearson Kristoffer Szilas department of Earth System Science University of ToyamaToyamaJapan X-Star Japan Agency for Marine-Earth Science and Technology(JAMSTEC)KanagawaJapan Faculty of Geosciences and Civil Engineering Kanazawa UniversityKanazawaJapan Lamont-doherty Earth Observatory Columbia UniversityPalisadesUSA Volcanoes and Earth’s Interior Research Center JAMSTECKanagawaJapan department of Earth and Atmospheric Sciences University of AlbertaEdmontonCanada Canadian Centre for Isotopic Microanalysis University of AlbertaEdmontonCanada National Museum of Nature and Science TsukubaJapan department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark

The Ujaragssuit Nunat layered(UNL)unit in the Itsaq Gneiss Complex,west Greenland,has been consid-ered to contain one of the oldest chromitites on Earth based on~ca.4.1 Ga Hadean whole rock Pt-Os model ages and ca.3.81 Ga zircon U-Pb age of the surrounding *** study obtained zircon from the chromitite within this unit as well as granitoid sheets that intruded into the UNL ***-situ U-Pb-Hf-O isotope measurements were made on the *** from both the chromitite and the intrusive granitoids show concordant U-Pb ages of ca.2.97-2.95 *** contrast,Hf and 0 isotopic anal-yses indicate that zircons in the chromitites have a different origin from those in the intrusive *** from granitoids yielded Th/U ratios higher than 0.2,initial Hf isotope ratios of 0.2805-0.2807(i.e,initial:Hf value of-11 to-5),andδ^(18)O values of mostly 6.0‰-7.0‰,which are typical for felsic igneous rocks in Archean continental *** least altered zircons from a chromitite exhibited initial Hf isotope ratios of 0.28078-0.28084(i.e.,initial:Hf value of-1.1 to-0.4),close the chondritic value at ca.3.0 Ga and the depleted mantle at ca.3.2 *** zircons also haveδ^(18)O values of 4.2‰6.1‰which correspond to typical mantle *** other chromitite zircons yielded Th/U ratios lower than 0.1,and Hf and 0 isotopic compositions ranging between the least altered zircons and the intrusive granitoid *** results indicate that the zircons in the chromitites crystallized before or during the 2.97-2.95 Ga granitoid intrusion and most of the zircons were altered by subsequent ***,the present results suggest that zircons in the chromitites originally had depleted Hf iso-topic compositions at ca.3.2-3.0 *** can be explained by two different models of the evolution of the UNL *** is that if the UNL unit was formed at>3.81 Ga as previously thought,with the zircons in the chromitites subsequently being precipitated by ca.3.2-2.95 G

关键词： Archean Itsaq gneiss complex Ultramafic rock Metasomatism

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deserpentinization and high-pressure(eclogite-facies) metamorphic features in the Eoarchean ultramafic body from Isua,Greenland

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Geoscience Frontiers 2022年第1期13卷 297-309页

作者： Juan Miguel Guotana Tomoaki Morishita Ikuya Nishio Akihiro Tamura Tomoyuki Mizukami Kenichiro Tani Yumiko Harigane Kristoffer Szilas d.graham pearson Graduate School of Natural Science&Technology Kanazawa UniversityJapan School of Environmental Science and Management University of the Philippines Los BañosLagunaPhilippines Lamont-doherty Earth Observatory Columbia UniversityPalisadesNY 10964USA Volcanoes and Earth’s Interior Research Center Japan Agency for Marine-Earth Science and Technology2-15 NatsushimaKanagawa 237-0061Japan National Museum of Nature and Science 4-1-1AmakuboTsukuba-shiIbaraki 305-0005Japan Institute of Geology and Geoinformation Geological Survey of Japan/AIST Central 71-1-1 HigashiTsukubaIbaraki 305-8567Japan department of Geosciences and Natural Resource Management University of CopenhagenØster Voldgade 101350 CopenhagenDenmark department of Earth&Atmospheric Sciences University of AlbertaEdmontonABCanada

discontinuous chains of ultramafic rock bodies form part of the 3800–3700 Ma Isua Supracrustal Belt(ISB),hosted in the Itsaq Gneiss Complex of southwestern *** bodies are among the world’s oldest outcrops of ultramafic rocks and hence an invaluable geologic *** rocks from Lens B in the northwestern limb of ISB show characteristics of several stages of serpentinization and deserpentinization forming prograde and retrograde mineral ***-rich humite-group minerals such as titanian chondrodite(Ti-Chn)and titanian clinohumite(Ti-Chu)often occur as accessory phases in the metamorphosed ultramafic *** Ti-rich humite minerals are associated with metamorphic *** host olivine is highly forsteritic(Fo96-98)with variable Mn O and Ni O *** concentrations of the rare-earth elements(REE)and high-field strength elements(HFSE)of the metamorphic olivine are higher than typical mantle *** textural and chemical characteristics of the olivine indicate metamorphic origin as a result of deserpentinization of a serpentinized ultramafic protolith rather than primary assemblage reflecting mantle residues from high-degrees of partial *** close association of olivine,antigorite and intergrown Ti-Chn and Ti-Chu suggests pressure condition between$1.3–2.6 GPa within the antigorite stability field(d geochemical features of Lens B ultramafic body within the Eoarchean ISB indicate that these are allochthonous ultramafic rocks that recorded serpentine dehydration at relatively lower temperature and reached eclogite facies condition during their complex metamorphic history similar to exhumed UHP ultramafic rocks in modern subduction zone channels.

关键词： Titanian chondrodite Titanian clinohumite Isua supracrustal belt UHP deserpentinization

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Exploring emerald global geochemical provenance through fingerprinting and machine learning methods

Artificial Intelligence in Geosciences

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Artificial Intelligence in Geosciences 2024年第1期5卷 202-219页

作者： Raquel Alonso-Perez James M.d.day d.graham pearson Yan Luo Manuel A.Palacios Raju Sudhakar Aaron Palke Earth and Planetary Science department Harvard UniversityCambridgeMA02138USA Scripps Institution of Oceanography University of California San DiegoLa JollaCA92037USA University of Alberta EdmontonABT6G 2R3Canada Eigenvector Research Inc.Manson WA98831USA Rockhurst University Kansas CityMO64110USA Gemological Institute of America CarlsbadCA92008USA

Emeralds-the green colored variety of beryl-occur as gem-quality specimens in over fifty deposits *** digital traceability methods for emerald have limitations,sample-based approaches offer robust alterna-tives,particularly for determining the geographic origin of *** factors make emerald suitable for provenance studies and hence for developing models for origin ***,the diverse elemental chemistry of emerald at minor(d trace levels(destructive techniques,including laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS),enable measurement of these diagnostic elemental ***,when applied to extensive datasets,machine learning(ML)techniques enable the creation of predictive models and statistical discrimination with adequate characterization of the *** study em-ploys a carefully selected dataset comprising more than 1000 LA-ICP-MS analyses of gem-quality emeralds,enriched with new *** dataset represents the largest available for global emerald *** con-ducted unsupervised exploratory analysis using Principal Component Analysis(PCA).For machine learning-based classification,we employed Support Vector Machine Classification(SVM-C),achieving an initial accu-racy rate of 79%.This was enhanced to 96.8%through the use of hierarchical SVM-C with PCA filters as our modeling *** ML models were trained using the concentrations of eight statistically significant ele-ments(Li,V,Cr,Fe,Sc,Ga,Rb,Cs).By leveraging high-quality LA-ICP-MS data and ML techniques,accurate identification of the geographical origin of emerald becomes *** models are important for accurate provenance of emerald,and from a geochemical perspective,for understanding the formation environments of beryl-bearing pegmatites and shales.

关键词： Beryl Provenance LA-ICP-MS Machine learning Multivariate analysis Trace elements

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Long-lived kimberlite magmatism in the Central Saskatchewan area（central North America） recorded by zircon megacrysts from the Fort à la Corne field

Long-lived kimberlite magmatism in the Central Saskatchewan ...

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第八届全国成矿理论与找矿方法学术讨论会

作者：舒巧 d.graham pearson Bruce A.Kjargaard Greg Read Institute of Geochemistry Chinese Academy of Sciences dept. of Earth and Atmospheric Sciences University of Alberta Geological Survey of Canada

＜正＞Zircon megacrysts from kimberlites appear to have a direct relationship to the magmatic activity that lead to the eruption of their host kimberlites because i)they yield kimberlite eruption ages（davis,1977）and ii)their trace element patterns and contents significantly differ from crustal zircons,most significantly by the absence of a negative Eu anomaly（Belousova et al.,2002）.These are also the features of a large suite of zircon megacrysts separated during ore-body evaluation from the kimberlites of Fortàla Corne,central Saskatchewan that erupt

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Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report

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Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： Pascal J.Goldschmidt-Clermont Aisha Khan George Jimsheleishvili Patricia graham Adriana Brooks Risset Silvera Alexander J.P.Goldschmidt damien d.Pearse W.dalton dietrich Allan d.Levi James d.Guest Miller School of Medicine University of MiamiMiamiFLUSA Stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The Miami Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann cell function may also be ***,important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been *** case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral *** initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and *** patient volunteered to participate in an FdA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron *** confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in *** a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrophic lateral sclerosis exosomes infusion neuromuscular junction Schwann cell

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Two decades of compositional and structural change in deciduous old-growth forests of Indiana,USA

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Journal of Plant Ecology 2016年第3期9卷 256-271页

作者： Christy A.Lowney Bradley d.graham Martin A.Spetich Stephen R.Shifley Michael R.Saunders Michael A.Jenkins department of Forestry and Natural Resources and Hardwood Tree Improvement and Regeneration Center Purdue University715 West State StreetWest Lafayette IN 47907USA Arkansas Forestry Sciences Laboratory USDA Forest ServiceSouthern Research StationP.O.Box 1270Hot SpringsAR 71902USA USdA Forest Service Northern Research Station202 ABNR BuildingColumbiaMO 65201USA

Aims Using a network of permanent plots,we determined how multiple old-growth forests changed over an 18-19-year period at a state-wide *** examination of change allowed us to assess how the compositional and structural stability of each forest varied with site characteristics(topography,physiography and productivity)and stochastic *** In 2011,we resampled 150 plots distributed across five old-growth hardwood forests in Indiana,USA that were originally sampled in *** each plot,we relocated and remeasured the diameter at breast height(dbh)of all trees(≥10.0 cm)present during the 1992-1993 sample,which allowed us to track their individual fates through time for growth and mortality *** that grew to≥10.0 cm dbh since plot establishment were designated as *** dbh and species of all saplings(stems≥2.0 cm butdbh)were also *** each forest,we calculated density(stems ha^(−1)),basal area(BABA;m^(2)ha^(−1))and importance value(relative density+relative BABA)/2 of trees by *** saplings,density per ha was calculated by species for each *** also calculated annual mortality rate(AMR)for three diameter classes(10-29.9,30-59.9 and≥60 cm)and species richness(S),evenness(E)and Shannon-Weiner diversity(H')for the tree and sapling *** between years were compared for each forest using paired t-tests and Wilcoxon signed rank *** FindingsAlthough we observed commonality in changes across some sites,our results suggest that these forests differ in their rates and trajectories of *** in total stand BABA and density varied across sites and were influenced by past disturbance and mortality *** observed a general increase in the overstory dominance of Acer saccharum coupled with a general decrease in the dominance of Quercus section Lobatae(red oak group)*** of overstory trees present in 1992-1993 ranged from 27%to 49%over the study period(mean AM

关键词： forest remnants forest structure long-term data mortality species diversity stand development.

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A link between the destruction of the mantle root beneath the North China Craton and the Cretaceous Greenhouse

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National Science Review 2022年第6期9卷 7-7页

作者： d.graham pearson department of Earth and Atmospheric Sciences University of Alberta

The carbon dioxide level in Earth’s atmosphere has long been recognized as a key driver of modern climate. However, the amount of carbon trapped in the solid Earth constitutes over 99.99% of all Earth’s carbon and thus dwarfs that in the atmosphere. Recognition of the key role played by this vast source of COhas increased our need to understand the interplay between the solid Earth and the atmosphere [1].

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Comments on ‘Enhanced piezoresistivity in Ni-silicone rubber composites’

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Chinese Physics B 2010年第1期19卷 431-432页

作者： d.Bloor A.graham P.J. Laughlin d.Lussey department of Physics Durham University Peratech Ltd Old Repeater StationBrompton-on-SwaleDL10 7JHUK

This paper describes the accepted meaning of the term ＇negative resistance＇ and its use in the literature, and discusses the features in the previously published data on QTC^TM （market name of a metal-polymer composite） that show that the non-linear, hysteretic current voltage characteristics are not caused by Joule heating. The benefit of the high metal filler loading in QTC^TM and other unique features of this composite are reviewed.

关键词： I V characteristics quantum tunnelling oiezoresitivity

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Role of ischaemic preconditioning in liver regeneration following major liver resection and transplantation

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World Journal of Gastroenterology 2007年第5期13卷 657-670页

作者： d Gomez S Homer-Vanniasinkam AM graham KR Prasad department of Hepatobiliary Surgery and Transplantation St. James’s University Hospital United Kingdom department of Vascular Surgery Leeds General Infirmary Leeds United Kingdom department of Biomedical Sciences University of Bradford Bradford United Kingdom

Liver ischaemic preconditioning （IPC） is known to protect the liver from the detrimental effects of ischaemic-reperfusion injury （IRI）, which contributes significantly to the morbidity and mortality following major liver surgery. Recent studies have focused on the role of IPC in liver regeneration, the precise mechanism of which are not completely understood. This review discusses the current understanding of the mechanism of liver regeneration and the role of IPC in this setting. Relevant articles were reviewed from the published literature using the Medline database. The search was performed using the keywords ＂liver＂, ＂ischaemic reperfusion＇, ＂ischaemic preconditioning＂, ＂regeneration＂, ＂hepatectomy＂ and ＂transplantation＂. The underlying mechanism of liver regeneration is a complex process involving the interaction of cytokines, growth factors and the metabolic demand of the liver. IPC, through various mediators, promotes liver regeneration by up-regulating growth-promoting factors and suppresses growth-inhibiting factors as well as damaging stresses. The increased understanding of the cellular mechanisms involved in IPC will enable the development of alternative treatment modalities aimed at promoting liver regeneration following major liver resection and transplantation.

关键词： Liver regeneration Ischaemic reperfusion Lschaemic preconditioning Hepatectomy Transplantation

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High-resolution two-photon polymerization:the most versatile technique for the fabrication of microneedle arrays

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Microsystems & Nanoengineering 2021年第5期7卷 1-17页

作者： Zahra Faraji Rad Philip d.Prewett graham J.davies School of Mechanical and Elearical Engineering University of Southern QueenslandSpringfield CentralQLD 4300Australia department of Mechanical Engineering University of BirminghamBirmingham B152TTUK Oxacus Ltd Dorchester-on-Thames 0X107HNUK Faculty of Engineering UNSW AustraliaKensingtonNSW 2052Australia College of Engineering and Physical Sciences School of EngineeringUniversity of BirminghamBirmingham B152TTUK

Microneedle patches have received much interest in the last two decades as drug/vaccine delivery or fluid sampling systems for diagnostic and monitoring *** are manufactured using a variety of additive and subtractive micromanufacturing *** the last decade,much attention has been paid to using additive manufacturing techniques in both research and industry,such as 3d printing,fused deposition modeling,inkjet printing,and two-photon polymerization(2PP),with 2PP being the most flexible method for the fabrication of microneedle arrays.2PP is one of the most versatile and precise additive manufacturing processes,which enables the fabrication of arbitrary three-dimensional(3d)prototypes directly from computer-aided-design(CAd)models with a resolution down to 100 *** to its unprecedented flexibility and high spatial resolution,the use of this technology has been widespread for the fabrication of bio-microdevices and bio-nanodevices such as microneedles and microfluidic *** is a pioneering transformative technology that facilitates the fabrication of complex miniaturized structures that cannot be fabricated with established multistep manufacturing methods such as injection molding,photolithography,and ***,microstructures are designed according to structural and fluid dynamics considerations rather than the manufacturing constraints imposed by methods such as machining or etching *** article presents the fundamentals of 2PP and the recent development of microneedle array fabrication through 2PP as a precise and unique method for the manufacture of microstructures,which may overcome the shortcomings of conventional manufacturing processes.

关键词： resolution needle additive

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