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A geochemical perspective on the genesis of Cenozoic basic volcanism in northeastern Turkey:an overview of metasomatism and heterogeneity of the sub-continental lithospheric mantle in a post-collisional setting
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作者 Mehmet Arslan Irfan Temizel 《Acta Geochimica》 EI CAS CSCD 2024年第3期489-506,共18页
The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of su... The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of sub-continental lithospheric mantle(SCLM)sources and parental melt generation.So far,the traditional whole-rock lithophile geochemical data of these basic volcanic rocks have provided important constraints on the nature of SCLM sources.Integrated lithophile element and HSE geochemical data of these basic volcanic rocks also reveal the heterogeneity of the SCLM source,which is principally related to variable metasomatism resulting from previous subduction(s)and post-collisional mantle-crust interactions in an extensional setting.Lithophile element geochemical features suggest that the parental magmas have derived from metasomatized spinel-to garnet-bearing SCLM sources for Eocene and Miocene basic volcanic rocks with subduction signatures whereas originated from spinel-to garnet-bearing SCLM sources for Mio-Pliocene and Plio-Quaternary basaltic volcanic rocks without the subduction signature.Lithophile element and HSE geo-chemistry also reveal that Eocene and Miocene basic vol-canic rocks were affected by more pronounced crustal contamination than the basaltic volcanic rocks of Mio-Pliocene and Quaternary.Furthermore,the integrated lithophile element and HSE compositions of these basic volcanic rocks,together with the regional asymmetric lithospheric delamination model,reveal that the compositional variation(especially due to metasomatism)was significant temporally in the heterogeneity of the SCLM sources from which parental magmas formed during the Cenozoic era. 展开更多
关键词 BASALT Lithospheric mantle METASOMATISM mantle heterogeneity Cenozoic volcanics NE Turkey
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SENP3 Promotes Mantle Cell Lymphoma Development through Regulating Wnt10a Expression
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作者 Yan-ni MA Yun-ding ZOU +7 位作者 Zhi-long LIU Gui-xian WU Yuan-ze ZHOU Cheng-xin LUO Xiang-tao HUANG Ming-ling XIE Shuang-nian XU Xi LI 《Current Medical Science》 SCIE CAS 2024年第1期134-143,共10页
Objective SUMO-specific protease 3(SENP3),a member of the SUMO-specific protease family,reverses the SUMOylation of SUMO-2/3 conjugates.Dysregulation of SENP3 has been proven to be involved in the development of vario... Objective SUMO-specific protease 3(SENP3),a member of the SUMO-specific protease family,reverses the SUMOylation of SUMO-2/3 conjugates.Dysregulation of SENP3 has been proven to be involved in the development of various tumors.However,its role in mantle cell lymphoma(MCL),a highly aggressive lymphoma,remains unclear.This study was aimed to elucidate the effect of SENP3 in MCL.Methods The expression of SENP3 in MCL cells and tissue samples was detected by RT-qPCR,Western blotting or immunohistochemistry.MCL cells with stable SENP3 knockdown were constructed using short hairpin RNAs.Cell proliferation was assessed by CCK-8 assay,and cell apoptosis was determined by flow cytometry.mRNA sequencing(mRNA-seq)was used to investigate the underlying mechanism of SENP3 knockdown on MCL development.A xenograft nude mouse model was established to evaluate the effect of SENP3 on MCL growth in vivo.Results SENP3 was upregulated in MCL patient samples and cells.Knockdown of SENP3 in MCL cells inhibited cell proliferation and promoted cell apoptosis.Meanwhile,the canonical Wnt signaling pathway and the expression of Wnt10a were suppressed after SENP3 knockdown.Furthermore,the growth of MCL cells in vivo was significantly inhibited after SENP3 knockdown in a xenograft nude mouse model.Conclusion SENP3 participants in the development of MCL and may serve as a therapeutic target for MCL. 展开更多
关键词 mantle cell lymphoma SENP3 cell proliferation APOPTOSIS
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Early Cretaceous Metasomatized Lithospheric Mantle beneath the Central Jiangnan Orogen in South China:Geochemical and Sr-Nd Isotope Evidence from the Tuanshanbei Dolerite
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作者 WANG Cheng WEI Hantao +1 位作者 LIU Qingquan YANG Zhao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期602-616,共15页
It is well established that Cretaceous magmatism in the South China Block(SCB)is related to the Paleo-Pacific subduction.However,the starting time and the associated deep crust-mantle processes are still debatable.Maf... It is well established that Cretaceous magmatism in the South China Block(SCB)is related to the Paleo-Pacific subduction.However,the starting time and the associated deep crust-mantle processes are still debatable.Mafic dike swarms carry important information on the deep earth(including mantle)geodynamics and geochemical evolution.In the Jiangnan Orogen(South China).there is no information on whether the Mesozoic magmatic activities in this region are also directly related to the Pacific subduction or not.In this study,we present detailed zircon U-Pb geochronological,wholerock element and Sr-Nd isotope data for Early Cretaceous Tuanshanbei dolerite dikes,and provide new constraints on the condition of the lithospheric mantle and mantle dynamics of the SCB during that time.LA-ICP-MS zircon U-Pb dating suggests that this dolerite erupted in the Early Cretaceous(~145 Ma).All samples have alkaline geochemical affinities with K_(2)O+Na_(2)O=3.11-4.04 wt%,K_(2)O/Na_(2)O=0.50-0.72,and Mg^(#)=62.24-65.13.They are enriched in LILE but depleted in HFSE with higher initial^(87)Sr/^(86)Sr ratio(0.706896-0.714743)and lower ε_(Nd)(t)(-2.61 to-1.67).They have high Nb/U,Nb/La,La/Sm and Rb/Sr,and low La/Nb,La/Ta,Ce/Pb,Ba/Rb,Tb/Yb and Gd/Yb ratios.Such geochemical signatures suggest that the fractional crystallization is obvious but crustal contamination play a negligible role during magmatic evolution.Tuanshanbei dolerite were most likely derived from low-degree(2%-5%)partial melting of a phlogopite-bearing mantle material consisted of~85% spinel peridotite and~15% garnet peridotite previously metasomatized by asthenospherederived fluids/melts with minor subduction-derived fluids/melts.Slab-rollback generally lead to the upwelling of the hot asthenosphere.The upwelling of asthenosphere consuming the lithospheric mantle by thermo-mechanical-chemical erosion.The lithospheric mantle may have partially melted due to the heating by the upwelling asthenosphere and lithospheric extension.It is inferred that the Tuanshanbei dolerite might be associated with the initial slab rollback and corresponding lithospheric extension occurred potentially at ca.145 Ma. 展开更多
关键词 Early Cretaceous mafic dike metasomatized lithospheric mantle Tuanshanbei dolerite Jiangnan Orogen South China
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Molybdenum isotope composition of the upper mantle and its origin:insight from mid-ocean ridge basalt
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作者 Shuo CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期705-708,共4页
The molybdenum(Mo)isotope system is pivotal in reconstructing marine redox changes throughout Earth’s history and has emerged as a promising tracer for igneous and metamorphic processes.Understanding its composition ... The molybdenum(Mo)isotope system is pivotal in reconstructing marine redox changes throughout Earth’s history and has emerged as a promising tracer for igneous and metamorphic processes.Understanding its composition and variation across major geochemical reservoirs is essential for its application in investigating high-temperature processes.However,there is debate regarding theδ^(98/95)Mo value of the Earth’s mantle,with estimates ranging from sub-chondritic to super-chondritic values.Recent analyses of global mid-ocean ridge basalt(MORB)glasses revealed significantδ^(98/95)Mo variations attributed to mantle heterogeneity,proposing a two-component mixing model to explain the observed variation.Complementary studies confirmed the sub-chondriticδ^(98/95)Mo of the depleted upper mantle,suggesting remixing of subduction-modified oceanic crust as a plausible mechanism.These findings underscore the role of Mo isotopes as effective tracers for understanding dynamic processes associated with mantle-crustal recycling. 展开更多
关键词 molybdenum(Mo)isotope mantle crustal recycling mid-ocean ridge basalt(MORB)
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Seismic anisotropy and upper mantle dynamics in Alaska:A review of shear wave splitting analyses
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作者 Zhaofeng Jin Yuchen Yang +7 位作者 Muhammad Ishaidir Siregar Zihao Mu S.M.Ariful Islam Qichao Zhao Dan Wang Fan Zhang Xugang Yang Liwei Song 《Earthquake Research Advances》 CSCD 2024年第2期72-81,共10页
Shear wave splitting(SWS)is regarded as the most effective geophysical method to delineate mantle flow fields by detecting seismic azimuthal anisotropy in the earth's upper mantle,especially in tectonically active... Shear wave splitting(SWS)is regarded as the most effective geophysical method to delineate mantle flow fields by detecting seismic azimuthal anisotropy in the earth's upper mantle,especially in tectonically active regions such as subduction zones.The Aleutian-Alaska subduction zone has a convergence rate of approximately 50 mm/yr,with a trench length reaching nearly 2800 km.Such a long subduction zone has led to intensive continental deformation and numerous strong earthquakes in southern and central Alaska,while northern Alaska is relatively inactive.The sharp contrast makes Alaska a favorable locale to investigate the impact of subduction on mantle dynamics.Moreover,the uniqueness of this subduction zone,including the unusual subducting type,varying slab geometry,and atypical magmatic activity and composition,has intrigued the curiosity of many geoscientists.To identify different sources of seismic anisotropy beneath the Alaska region and probe the influence of a geometrically varying subducting slab on mantle dynamics,extensive SWS analyses have been conducted in the past decades.However,the insufficient station and azimuthal coverage,especially in early studies,not only led to some conflicting results but also strongly limited the in-depth investigation of layered anisotropy and the estimation of anisotropy depth.With the completion of the Transportable Array project in Alaska,recent studies have revealed more detailed mantle structures and characteristics based on the dense station coverage and newly collected massive seismic data.In this study,we review significant regional-and continental-scale SWS studies in the Alaska region and conclude the mantle flow fields therein,to understand how a geometrically varying subducting slab alters the regional mantle dynamics.The summarized mantle flow mechanisms are believed to be conducive to the understanding of seismic anisotropy patterns in other subduction zones with a complicated tectonic setting. 展开更多
关键词 Seismic anisotropy Shear wave splitting mantle flow Alaska subduction zone SLAB
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Experimental study on reactions between alkaline basaltic melt and orthopyroxenes: constraints on the evolution of lithospheric mantle in the North China Craton
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作者 Hanqi He Mingliang Wang Hongfeng Tang 《Acta Geochimica》 EI CAS CSCD 2024年第2期354-365,共12页
The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus ar... The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus are reported in this paper.The reactions are proposed to simulate the interactions between melts from the asthenospheric mantle and the lithospheric mantle.The starting melt in the experiments was made from the alkaline basalt occurring in Fuxin,Liaoning Province,and the orthopyroxenes were separated from the mantle xenoliths in Damaping,Hebei Province.The results show that clinopyroxenes were formed in all the reactions between the alkaline basaltic melt and orthopyroxenes under the studied P–T conditions.The formation of clinopyroxene in the reaction zone is mainly controlled by dissolution–crystallization,and the chemical compositions of the reacted melt are primarily infl uenced by the diff usion eff ect.Temperature is the most important parameter controlling the reactions between the melt and orthopyroxenes,which has a direct impact on the melting of orthopyroxenes and the diff usion of chemical components in the melt.Temperature also directly controls the chemical compositions of the newly formed clinopyroxenes in the reaction zone and the reacted melt.The formation of clinopyroxenes from the reactions between the alkaline basaltic melt and orthopyroxenes can result in an increase of CaO and Al_(2)O_(3) contents in the rocks containing this mineral.Therefore,the reactions between the alkaline basaltic melt from the asthenospheric mantle and orthopyroxenes from the lithospheric mantle can lead to the evolution of lithospheric mantle in the North China Craton from refractory to fertile with relatively high CaO and Al 2 O 3 contents.In addition,the reacted melts in some runs were transformed from the starting alkaline basaltic into tholeiitic after reactions,indicating that tholeiitic magma could be generated from alkaline basaltic one via reactions between the latter and orthopyroxene. 展开更多
关键词 Alkaline basaltic melt ORTHOPYROXENE Melt–mineral reaction High-temperature and high-pressure experiment Genesis of basalt Evolution of lithospheric mantle in the North China Craton
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Carbon Enrichment in the Lithospheric Mantle:Evidence from the Melt Inclusions in Mantle Xenoliths from the Hainan Basalts 被引量:1
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作者 XU Xin TIAN Wei +1 位作者 ZHANG Lifei LI Huijuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期358-375,共18页
It is generally believed that the lithospheric mantle and the mantle transition zone are important carbon reservoirs.However,the location of carbon storage in Earth's interior and the reasons for carbon enrichment... It is generally believed that the lithospheric mantle and the mantle transition zone are important carbon reservoirs.However,the location of carbon storage in Earth's interior and the reasons for carbon enrichment remain unclear.In this study,we report CO_(2)-rich olivine-hosted melt inclusions in the mantle xenoliths of late Cenozoic basalts from the Penglai area,Hainan Province,which may shed some light on the carbon enrichment process in the lithospheric mantle.We also present a detailed petrological and geochemical investigation of the late Cenozoic basalts and mantle xenoliths from northern Hainan Island.The collected samples of late Cenozoic Hainan Island basalts belong to both alkaline and subalkaline series,showing fractionated REE patterns with high(La/Yb)_(N)values of 3.52–11.77,which are typical for OIB.Based on Al-in-olivine thermometry,the temperatures estimated for the mantle xenoliths can be divided into two groups.One group has temperatures of less than 1050℃,and the other group has temperature ranging from 1050℃to 1282℃.Clinopyroxene(La/Yb)_(N)–Ti/Eu and clinopyroxene Ca/Al–Mg^(#)diagrams indicate that the mantle peridotite experienced metasomatism from both silicate and carbonate melts.Melt inclusions in the olivine of mantle xenoliths include(1)CO_(2)bubble–rich melt inclusions;(2)multiphase melt inclusions(glass+CO_(2)bubble+daughter minerals);(3)pure glass melt inclusions.Magnesite is a daughter mineral in the olivine-hosted melt inclusions,which could be interpreted as a secondary mineral formed by the interactions of CO_(2)-rich fluids with an olivine host,due to post-entrapment effects.The glasses in olivine-hosted melt inclusions have high SiO_(2)contents(60.21–77.72 wt%).Our results suggest that a considerable amount of CO_(2)-rich melt inclusions are captured in the lithospheric mantle during metasomatism.The lithospheric mantle can therefore act as is a‘carbon trap',with much CO_(2)being absorbed by the lithospheric mantle in this way. 展开更多
关键词 melt inclusions lithospheric mantle METASOMATISM carbon trap Hainan Island
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Mineralogical and Geochemical Constraints on the Mantle Source Characteristics of Basaltic Lavas from the Central Mariana Trough 被引量:1
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作者 LAI Zhiqing GAO Wei +3 位作者 HAN Zongzhu GUO Kun ZHONG Shihua ZHAO Guangtao 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1313-1325,共13页
The composition of mantle-derived basalts reflects the nature of their mantle source regions,which constrain magma generation and composition.Here we present a new whole rock major and trace elements and phenocryst co... The composition of mantle-derived basalts reflects the nature of their mantle source regions,which constrain magma generation and composition.Here we present a new whole rock major and trace elements and phenocryst composition of the basaltic lava in the central Mariana Trough.These data provide insights into the mantle source characteristics affected by subduction components.The rocks range from basalts to basaltic andesites,which have high subduction-mobile element contents(e.g.,K,U,Th,LREE)related to N-MORB.The calculated temperature and depth of magma generation are about 1300℃and 30 km,respectively.Although the results above suggest that the addition of hydrous fluid and/or a melt derived from a slab decreases the temperature of mantle partial melting and mildly modifies the composition of a mantle source,the mantle source lithology from which primary magma is generated remains to be peridotite. 展开更多
关键词 backarc basin basalt subduction component mantle lithology magma generation
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Petrogenesis of the Late Eocene to Early Oligocene Yao'an Shoshonitic Complex,Southeastern Tibet:Partial Melting of an Ancient Continental Lithospheric Mantle beneath the Yangtze Block 被引量:2
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作者 DONG Mengmeng YANG Tiannan +3 位作者 XUE Chuandong XIN Di LIANG Mingjuan YAN Qinggao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1657-1670,共14页
Cenozoic potassic-ultrapotassic igneous rocks are widespread in the southeastern Tibetan Plateau.Their petrogenesis and magmatic processes remain subject to debate in spite of numerous publications.Almost all of the C... Cenozoic potassic-ultrapotassic igneous rocks are widespread in the southeastern Tibetan Plateau.Their petrogenesis and magmatic processes remain subject to debate in spite of numerous publications.Almost all of the Cenozoic extrusive and intrusive rocks in the Yao’an area,western Yunnan Province,SW China,are geochemically shoshonitic,collectively termed here the Yao’an Shoshonitic Complex(YSC).The YSC is located in the(south)easternmost part of the ENE-WSW-trending,~550 km-long and~250 km-wide Cenozoic magmatic zone;the latter separates the orthogonal and oblique collision belts of the India-Eurasia collision orogen.Previously published geochronological and thermochronological data revealed that the rocks of the YSC were emplaced over a short timespan of 34-32 Ma.This and our new data suggest that the primary magma of the YSC likely was formed by partial melting of ancient continental lithospheric mantle beneath the Yangtze Block.This part of the continental lithospheric mantle had likely not been modified by any oceanic subduction.Fractionation crystallization of an Mg-and Ca-bearing mineral and TiFe oxides during the magmatic evolution probably account for the variable lithologies of the YSC. 展开更多
关键词 Ancient continental lithospheric mantle Partial melting Yao’an Shoshonitic Complex Late Eocene to early Oligocene SE Tibetan Plateau
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A global mantle conductivity model derived from 8 years of Swarm satellite magnetic data 被引量:1
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作者 HongBo Yao ZhengYong Ren +2 位作者 KeJia Pan JingTian Tang KeKe Zhang 《Earth and Planetary Physics》 EI CSCD 2023年第1期49-56,共8页
Mantle conductivity imaging is one of the scientific goals of the forthcoming Macao Science Satellite-1(MSS-1).To achieve this goal,we develop a data analysis and inversion scheme for satellite magnetic data to probe ... Mantle conductivity imaging is one of the scientific goals of the forthcoming Macao Science Satellite-1(MSS-1).To achieve this goal,we develop a data analysis and inversion scheme for satellite magnetic data to probe global one-dimensional(1D)mantle conductivity structures.Using this scheme,we present a new global mantle conductivity model by analyzing over 8 years of Swarm satellite magnetic data.First,after sophisticated data selection procedures and the removal of core and crustal fields,the inducing and induced spherical harmonic coefficients of magnetic potential due to the magnetospheric ring current are derived.Second,satellite Cresponses are estimated from the time series of these coefficients.Finally,the observed responses are inverted for both smooth and threejump conductivity models using a quasi-Newton algorithm.The obtained conductivity models are in general agreement with previous global mantle conductivity models.A comparison of our conductivity model with the laboratory conductivity model suggests the mean state of the upper mantle and transition zone is relatively dry.This scheme can be used to process the forthcoming Macao Science Satellite-1 magnetic data. 展开更多
关键词 Macao Science Satellite-1 satellite magnetic data mantle conductivity global electromagnetic induction
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The cooling models of Earth’s early mantle
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作者 Ting He Qingwen Zhang Yun Liu 《Acta Geochimica》 EI CAS CSCD 2023年第5期803-816,共14页
The thermal state of the early Earth’s interior and its way of cooling are crucial for its subsequent evo-lution.Earth is initially hot as it acquired enormous heat in response to violent processes during its formati... The thermal state of the early Earth’s interior and its way of cooling are crucial for its subsequent evo-lution.Earth is initially hot as it acquired enormous heat in response to violent processes during its formation,e.g.,the Moon-forming giant impact,the segregation and formation of its metallic core,the tidal interaction with the early Moon,and the decay of radioactive elements,etc.In the meantime,the cooling mechanisms of early Earth’s mantle remain elusive despite their importance,and the previously proposed cooling models of the mantle are controversial.In this paper,we first reviewed several prevalent parameter-ized thermal evolution models of the early mantle.The models give unrealistic predictions since they were estab-lished solely based on a single tectonic regime,such as the stagnant-lid regime,or relied on the disputable existence of the plate tectonics prior to-3.5 Ga.Then we argue that the mantle should have started to cool down from a very hot state after the solidification of the ferocious magma ocean.Instead of using one single scaling law to describe a single-stage model,we suggest that an episodic multi-stage cooling model(EMCM)of the early mantle could be more plausible to account for the mantle’s early cooling process.The model reconciles with the fact that the mantle cools down from a hot state prior to*3.5 Ga and can also explain the well-constrained post-3.5 Ga thermal history of the mantle. 展开更多
关键词 Thermal evolution mantle Parameterized model Episodic cooling Early mantle
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Transcriptome Analysis of Mantle Tissues Reveals Potential Shell-Matrix-Protein Genes in Gigantidas haimaensis
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作者 SHI Yu YAO Gaoyou HE Maoxian 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1087-1097,共11页
Haima cold seep ecosystem is on the northwestern slope of the South China Sea,which is characterised by high pressure,low temperature,hypoxia,and low pH value.The deep-sea mussel Gigantidas haimaensis is distributed i... Haima cold seep ecosystem is on the northwestern slope of the South China Sea,which is characterised by high pressure,low temperature,hypoxia,and low pH value.The deep-sea mussel Gigantidas haimaensis is distributed in this ecosystem.Previous studies have focused on its adaptation to abiotic stress,biogeography,ecotoxicology,genomes,immunity and symbiosis,but knowledge on biomineralisation remains lacking.Herein,we generated a comprehensive transcript dataset from G.haimaensis mantle tissue,and 30255 unigenes were assembled.The top 20 most highly expressed genes are related to energy supply,such as mitochondrial genes,suggesting they may mediate the adaptability of this deep-sea mussel to the high pressure and hypoxia environment.Eleven shell matrix protein(SMP)-related genes were identified from the transcriptome data.Quantitative PCR analyses showed that five of ten acidic SMPs and nacreous-layer-matrix-protein genes(nacrein,perlucin,perlwapin,pif and mantle protein)were highly expressed in mantle tissue,while the expressions of other five genes(chitinase,SPARC,TRY,papilin and calmodulin)were low.Scanning electron microscopy showed that the shell was composed of a prismatic layer and a nacreous layer,and every nacreous layer was made of the whole pieces of aragonite that stacked on top of each other.These results indicated the conservation of the structure and functions of nacreous matrix genes in G.haimaensis.Moreover,the nacreous layer was made of whole pieces of aragonite that were not quadrilateral or polygonal pieces.Studying these genes will likely reveal the molecular mechanisms of biomineralisation in G.haimaensis and other deep-sea mussels. 展开更多
关键词 Gigantidas haimaensis TRANSCRIPTOME BIOMINERALISATION mantle shell structure
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Pigment Distribution and Secretion in the Mantle of the Pacific Oyster(Crassostrea gigas)
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作者 ZHU Yijing LI Qi +1 位作者 YU Hong LIU Shikai 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期813-820,共8页
The color of Mollusca shells is one of the most important attributes to consumers.At the cellular level,black color is mainly from the melanin produced by melanocytes.The melanosome is a specialized membrane-bound org... The color of Mollusca shells is one of the most important attributes to consumers.At the cellular level,black color is mainly from the melanin produced by melanocytes.The melanosome is a specialized membrane-bound organelle that is involved in melanin synthesis,storage,and transportation.How the complex pigmentation process in the Crassostrea gigas is established remains an open question.The objectives of this studies are to examine the morphological characteristics of melanosomes or melanin of mantle pigmentation in the Pacific oyster,thereby investigating its contribution to shell color.The results show that pigmented granules of the mantles vary among the three lobes,and the melanosomes at different stages are enriched in distinct cargo molecules,which indicate the remarkable difference between the marginal mantle and central mantle.Examination of mantle histology reveals that the mantle margin of the oyster is characterized by three different folds,including the outer secretory,middle sensory,and inner muscular fold.Ferrous ion chelating assays against the tyrosine hydroxylase indicate that a large amount of melanin is localized in the inner surface of the middle fold.Transmission electron microscopy analyses show that the mantle edge is composed of tall columnar and cuboidal epidermal cells and some pigmented melanocytes intersperse among these cells.The numbers of melanosomes among the three lobes are different.In the inner fold and the middle fold of the mantle,some single dispersion,or aggregation of melanosomes with different degrees of melanization are found in the outer surface.Numerous melanosomes are distributed in the epithelium of the outer fold of the mantle,and mainly are at the apical microvillar surface near the lumen.However,melanosomes are occasionally observed in the central mantle,and they are relatively less.This work provides new insights into the process of melanin deposit in the mantle and shell pigmentation in C.gigas. 展开更多
关键词 Crassostrea gigas mantle MELANOSOME MELANIN PIGMENTATION cells
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Phase Stability and Reactions of Subducting CaCO_(3)under Upper Mantle Conditions
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作者 GUI Weibin SHEN Kewei LIU Jin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期309-315,共7页
CaCO_(3)is an important component of marine sediments and one of the major deep-carbon carriers at subduction zones.Some subducted CaCO_(3)can be dissolved in subduction fluids and recycled back to the surface via arc... CaCO_(3)is an important component of marine sediments and one of the major deep-carbon carriers at subduction zones.Some subducted CaCO_(3)can be dissolved in subduction fluids and recycled back to the surface via arc volcanoes degassing.At the same time,there still remain large amounts of CaCO_(3)and its reaction products,which could be further transported into Earth's deep interior.These internal processes link atmosphere,hydrosphere and biosphere with the deep solid Earth,modifying the environments of our planet.In this review,we summarize current understanding from high pressure-temperature experiments and field petrological observations on the physical and chemical properties of CaCO_(3).In particular,the phase stability and reactions of CaCO_(3)largely control the migration and reservation of oxidized carbon in subducting slabs.Finally,we present several critical but unsolved questions on CaCO_(3)subducting in the deep mantle. 展开更多
关键词 calcium carbonates phase stability subducting carbon upper mantle subduction zone
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Quaternary Intrusions from the Zhongjiannan Basin,South China Sea:Their Relationship with the Hainan Mantle Plume and Influence on Hydrocarbon Reservoirs
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作者 HE Yanxin LIU Jianping +1 位作者 WANG Lei TIAN Wei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期376-392,共17页
The transportation of magma in sedimentary basins often occurs through extensive dyke-sill networks.The role of sills on the plumbing system in rifted margins and the impact of sills on hydrocarbon reservoirs of prosp... The transportation of magma in sedimentary basins often occurs through extensive dyke-sill networks.The role of sills on the plumbing system in rifted margins and the impact of sills on hydrocarbon reservoirs of prospective sedimentary basins has long been an area of great industrial interest and scientific debate.Based on 2D seismic reflection,we present data on how the sills emplaced to form a magmatic plumbing system of the volcanic system for the Zhongjiannan Basin(ZJNB).The results show that sixty-nine sills and fourteen forced folds have been identified.The distribution and geometry of the sills suggest that magma flowed from west to east and then ascended to near the surface.The onlap relationship of the forced folds indicates that the timing of magmatic activities can be constrained at ca.0.2 Ma.The spatial and temporal occurrences of intrusions imply that the strong post-rift magmatism in ZJNB was associated with the Hainan mantle plume arising from the core-mantle boundary.Furthermore,these forced folds could produce several types of hydrocarbon traps,due to accommodation through bending and uplift of the overlying rock and free surface,but it is critical to evaluate the effect of such emplacement when setting exploration targets. 展开更多
关键词 sill intrusions forced fold petroleum traps Hainan mantle plume Zhongjiannan basin
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Vestiges of the Kerguelen Mantle Plume in Southern Tibet:Evidence from 123-117 Ma Magmatism in the Dingri Area of the Central Tethys Himalaya
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作者 YAN Songtao WU Qingsong +4 位作者 LI Hu DAI Xuejian ZHU Lidong WANG Jie XIN Chongyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1163-1180,共18页
The widely distributed Early Cretaceous magmatism in the Tethys Himalaya(TH)of southern Tibet is related to the Kerguelen mantle plume.Associated magmatic activity products are distributed in the eastern TH,where the ... The widely distributed Early Cretaceous magmatism in the Tethys Himalaya(TH)of southern Tibet is related to the Kerguelen mantle plume.Associated magmatic activity products are distributed in the eastern TH,where the active age is earlier than the peak ages of the Kerguelen mantle plume.This study investigated magmatic activity of the Dingri area in the central TH which was coeval with the Kerguelen mantle plume.The intrusion in the Dingri area contains diabases and monzonites.The zircon age of diabase is 123±1 Ma,and that of monzonite is 117±1 Ma.Geochemistry and Sr-Nd isotopic analyses show that the mafic-intermediate dikes were formed in an intraplate extensional environment.The diabase is derived from the enriched lithospheric mantle and monzonite is derived from partial melting of the lower crust,with both magmatic evolutions being contaminated by crustal materials.These characteristics are similar to those of the Rajmahal-Sylhet basalt,a typical Kerguelen mantle plume product.The discovery of the Dingri mafic-intermediate dikes of the central TH suggests that the TH and Rajmahal-Sylhet Traps formed a continuous mantle plume overflow magmatic belt which was a product of the continuous eruption of the Kerguelen mantle plume. 展开更多
关键词 GEOCHRONOLOGY mafic-intermediate dikes Kerguelen mantle plume central Tethys Himalaya East Gondwana
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Mantle sources of Cenozoic volcanoes around the South China Sea revealed by geochemical and isotopic data using the principal component analysis
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作者 Shuangshuang CHEN Zewei WANG +1 位作者 Rui GAO Yongzhang ZHOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期562-574,共13页
Principal component analysis(PCA)was employed to determine the implications of geochemical and isotopic data from Cenozoic volcanic activities in the Southeast Asian region,including China(South China Sea(SCS),Hainan ... Principal component analysis(PCA)was employed to determine the implications of geochemical and isotopic data from Cenozoic volcanic activities in the Southeast Asian region,including China(South China Sea(SCS),Hainan Island,Fujian-Zhejiang coast,Taiwan Island),and parts of Vietnam and Thailand.We analyzed 15 trace element indicators and 5 isotopic indicators for 623 volcanic rock samples collected from the study region.Two principal components(PCs)were extracted by PCA based on the trace elements and Sr-Nd-Pb isotopic ratios,which probably indicate an enriched oceanic island basalt-type mantle plume and a depleted mid-ocean ridge basalt-type spreading ridge.The results show that the influence of the Hainan mantle plume on younger volcanic activities(<13 Ma)is stronger than that on older ones(>13 Ma)at the same location in the Southeast Asian region.PCA was employed to verify the mantle-plume-ridge interaction model of volcanic activities beneath the expansion center of SCS and refute the hypothesis that the tension of SCS is triggered by the Hainan plume.This study reveals the efficiency and applicability of PCA in discussing mantle sources of volcanic activities;thus,PCA is a suitable research method for analyzing geochemical data. 展开更多
关键词 volcanic rocks geochemical indicators mantle source principal component analysis South China Sea
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Discovery of Early Tonian Calc-alkaline and Shoshonitic Metamafic Rocks from the North Purulia Shear Zone,Chhotanagpur Gneissic Complex,Eastern India:Implications of Proterozoic Sub-continental Lithospheric Mantle
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作者 Bapi GOSWAMI Susmita DAS +1 位作者 Ankita BASAK Chitta BHATTACHARYYA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期68-89,共22页
Reports of shoshonitic rocks in Precambrian terrains are relatively rare.Pl-Grt amphibolites and Hbl-Bt mafic granulites occurring in the migmatitic gneisses of the Chhotanagpur Gneissic Complex(CGC)show calc-alkaline... Reports of shoshonitic rocks in Precambrian terrains are relatively rare.Pl-Grt amphibolites and Hbl-Bt mafic granulites occurring in the migmatitic gneisses of the Chhotanagpur Gneissic Complex(CGC)show calc-alkaline and shoshonitic characteristics.Relict porphyritic,sub-ophitic and poikilitic textures are noted in these rocks.Their parent magma was emplaced during the waning phase of the regional metamorphism.Geochemically,these metamafics are similar to the GroupⅢpotassic and ultrapotassic rocks of Foley et al.(1987).The magma was derived from the metasomatized subcontinental lithospheric mantle(SCLM).Subduction-related sediment melts metasomatized the SCLM.Compositionally,the SCLM is a metasomatized phlogopite-amphibole-spinel-bearing harzburgite.1%–5%batch melting of the SCLM could produce the parental magma of the mafic granulites.Pressures and temperatures of metamorphic equilibration were carried out by pseudosection modeling.Peak metamorphic assemblage(M_(1):Grt-Cpx-Pl-Qz)in garnetiferous amphibolite equilibrated at 740℃and 8.7 kbar.The Cpx-Pl corona appeared around the garnet during decompression(M_(2):655℃,6 kbar).The Hbl-Pl symplectites around garnet formed during isobaric cooling(M_(3):580℃and 5.9 kbar).The emplacement of shoshonitic magma and subsequent decompression happened at the slab break-off stage of continental collision(~990 Ma). 展开更多
关键词 calc-alkaline-shoshonitic magma amphibolite-granulite facies metamorphism POST-COLLISIONAL early Tonian eastern Indian Shield sub-continental lithospheric mantle
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Synchronous rectal adenocarcinoma and intestinal mantle cell lymphoma:A case report
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作者 Kim-Van Vu Nguyen-Van Trong +5 位作者 Nguyen-Thi Khuyen Do Huyen Nga Hoang Anh Nguyen Tien Trung PhamTrung Thong Nguyen Minh Duc 《World Journal of Clinical Cases》 SCIE 2023年第24期5772-5779,共8页
BACKGROUND Mantle cell lymphoma(MCL)of the gastrointestinal tract is a rare malignancy,accounting for about 0.2%of malignant colorectal tumors.MCL synchronous with rectal adenocarcinoma is extremely rare.We know of on... BACKGROUND Mantle cell lymphoma(MCL)of the gastrointestinal tract is a rare malignancy,accounting for about 0.2%of malignant colorectal tumors.MCL synchronous with rectal adenocarcinoma is extremely rare.We know of only a few cases reported in the literature.We describe the case of a patient with synchronous rectal adenocarcinoma and intestinal MCL.CASE SUMMARY A 63-year-old man was admitted to our hospital due to abdominal pain and hematochezia over the past month.The patient was diagnosed with middle rectal cancer cT2N0M0 and underwent surgery.However,we found a large tumor in the small intestine during surgery.The patient underwent total mesorectal excision for rectal cancer and resectioning of the ileal segment containing the large mass.Pathology and immunohistochemistry revealed the presence of both rectal adenocarcinoma and pathognomonic MCL stage IIE presenting as multiple lymphomatous polyposis.The patient subsequently underwent RDHAP/RCHOP chemotherapy and was maintained with rituximab.A Positron Emission Tomography and Computed Tomography(PET/CT)scan showed that the disease responded well to treatment without tumor-increased metabolism in the gastrointestinal tract.CONCLUSION Synchronous rectal adenocarcinoma and intestinal MCL presenting as multiple lymphomatous polyposis are extremely rare.MCL is often discovered fortuitously when rectal cancer is diagnosed.The coexistence of these tumors poses treatment challenges. 展开更多
关键词 mantle cell lymphoma Multiple lymphomatous polyposis Rectal adenocarcinoma SYNCHRONOUS Gastrointestinal tract Case report
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油棕组培苗Mantled变异研究进展 被引量:2
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作者 张大鹏 王永 +2 位作者 石鹏 金龙飞 曹红星 《热带农业科学》 2017年第12期52-55,69,共5页
油棕作为高产木本油料作物,因其较长的育种周期,组织培养技术成为遗传改良的主要手段,但该技术存在Mantled变异问题。从Mantled变异的出现与形态特征、Mantled变异的分子标记研发、Mantled变异候选基因的推定、油棕的表观遗传学四个方... 油棕作为高产木本油料作物,因其较长的育种周期,组织培养技术成为遗传改良的主要手段,但该技术存在Mantled变异问题。从Mantled变异的出现与形态特征、Mantled变异的分子标记研发、Mantled变异候选基因的推定、油棕的表观遗传学四个方面综述了Mantled变异当前的研究现状,并对后续研究做出了展望。随着油棕转座子基因karma功能的确定,Mantled变异早期检测技术将成为后续研究重点,恢复基因功能和开发分子标记用于剔除变异苗将是Mantled变异的两个重要研究方向。而早期检测技术的突破,将有利于推动油棕产业的发展。 展开更多
关键词 油棕 组织培养 mantled 体细胞变异
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