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Petrology of ultramafic to mafic cumulate rocks from the G?ksun(Kahramanmaras) ophiolite,southeast Turkey 被引量:3
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作者 Osman Parlak Utku Bagcı +4 位作者 Tamer Rızaoglu Corina Ionescu GüzideÖnal Volker Höck Hüseyin Kozlu 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第1期109-128,共20页
The G?ksun(Kahramanmaras)ophiolite(GKO),cropping out in a tectonic window bounded by the Malatya metamorphic unit on both the north and south,is located in the EW-trending lower nappe zone of the southeast Anatolian o... The G?ksun(Kahramanmaras)ophiolite(GKO),cropping out in a tectonic window bounded by the Malatya metamorphic unit on both the north and south,is located in the EW-trending lower nappe zone of the southeast Anatolian orogenic belt(Turkey).It exhibits a complete oceanic lithospheric section and overlies the Middle Eocene Maden Group/Complex with a tectonic contact at its base.The ophiolitic rocks and the tectonically overlying Malatya metamorphic(continental)unit were intruded by I-type calc-alkaline Late Cretaceous granitoid(~81-84 Ma).The ultramafic to cumulates in the GKO are represented by wehrlite,plagioclase wehrlite,olivine gabbro and gabbro.The crystallization order for the cumulate rocks is as follows:olivine±chromian spinel→clinopyroxene→plagioclase.The major and trace element geochemistry as well as the mineral chemistry of the ultramafic to mafic cumulate rocks suggest that the primary magma generating the GKO is compositionally similar to that observed in the modern island-arc tholeiitic sequences.The mineral chemistry of the ultramafic to mafic cumulates indicates that they were derived from a mantle source that was previously depleted by earlier partial melting events.The highly magnesian olivine(Fo77-83),clinopyroxene(Mg#of 82-90)and the highly Ca-plagioclase(An81-89)exhibit a close similarity to those,which formed in a supra-subduction zone(SSZ)setting.The field and the geochemical evidence suggest that the GKO formed as part of a much larger sheet of oceanic lithosphere,which accreted to the base of the Tauride active continental margin,including the ispendere,K?mürhan and the Guleman ophiolites.The latter were contemporaneous and genetically/tectonically related within the same SSZ setting during the closure of the Neotethyan oceanic basin(Berit Ocean)between the Taurides to the north and the Bitlis-Pütürge massif to the south during the Late Cretaceous. 展开更多
关键词 Göksun(Kahramanmaras)ophiolite cumulate SSZ-Spreading NEOTETHYS Late Cretaceous SE Anatolia
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The lithology and composition of lunar mantle modified by ilmenite bearing cumulate:A thermodynamic model 被引量:1
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作者 Wei Huang Wei Du 《Acta Geochimica》 EI CAS CSCD 2024年第5期856-875,共20页
Due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar ... Due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar mantle overturn.Geophysical evidence implied that IBC may descend deep inside the Moon and remain as a partially molten layer at the core-mantle boundary(CMB).However,partial melting may have occurred on the mixed mantle cumulates during the sinking of IBC/KREEP and the silicate melt may be positively buoyant,thus preventing the IBC/KREEP layer from sinking to the CMB.Here,we perform thermodynamic simulation on the stability of lunar mantle cumulates at different depths mixed with different amounts of IBC/KREEP from an updated LMO model.The modeling results suggest that the sinking of IBC/KREEP will cause at least 5 wt%partial melting in the shallow(~120 km)and a much larger degree of partial melting in the deep lunar mantle(~420 km).Due to the density contrast with the surrounding mantle,IBC/KREEP-bearing melts could potentially decouple under certain conditions.The modified lunar mantle by sinking of IBC/KREEP can better explain the formation of different kinds of lunar basaltic magma than the primary lunar mantle formed through differentiation of lunar magma ocean.Sinking of IBC/KREEP back into the lunar mantle may introduce plagioclase,clinopyroxene,garnet,and incompatible radioactive elements into the deep lunar mantle,which will further affect the thermal and chemical evolution of the lunar interior. 展开更多
关键词 Ilmenite-bearing cumulate KREEP Partial melting Lunar mantle overturn pMELTS
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The First Discovery of Sulfide Inclusions within Apatite from Hornblende Cumulated Crystals 被引量:1
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作者 DU Jingguo CAO Yi DU Yangsong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1931-1932,共2页
Objective Sulfide inclusions within natural mineral phases play important roles in exploring the origin of magmatic sulfides ores,tracing the distribution of sulfur in mantle or crust and understanding continental man... Objective Sulfide inclusions within natural mineral phases play important roles in exploring the origin of magmatic sulfides ores,tracing the distribution of sulfur in mantle or crust and understanding continental mantle evolution(partial melting and metasomatism in upper mantle).Until now,varieties of sulfide inclusions have been extensively discovered in the ultramafic or mafic phenocrysts. 展开更多
关键词 The First Discovery of Sulfide Inclusions within Apatite from Hornblende cumulated Crystals
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Petrology and geochemistry of mafic and ultramafic cumulate rocks from the eastern part of the Sabzevar ophiolite(NE Iran): Implications for their petrogenesis and tectonic setting
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作者 Fatemeh Rahmani Mohamad Ali Mackizadeh +2 位作者 Moussa Noghreyan Claudio Marchesi Carlos J.Garrido 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第6期2347-2364,共18页
The Late Cretaceous Sabzevar ophiolite represents one of the largest and most complete fragments of Tethyan oceanic lithosphere in the NE Iran.It is mainly composed of serpentinized mantle peridotites slices;nonethele... The Late Cretaceous Sabzevar ophiolite represents one of the largest and most complete fragments of Tethyan oceanic lithosphere in the NE Iran.It is mainly composed of serpentinized mantle peridotites slices;nonetheless,minor tectonic slices of all crustal sequence constituents are observed in this ophiolite.The crustal sequence contains a well-developed ultramafic and mafic cumulates section,comprising plagioclase-bearing wehrlite,olivine clinopyroxenite,olivine gabbronorite,gabbronorite,amphibole gabbronorite and quartz gabbronorite with adcumulate,mesocumulate,heteradcumulate and orthocumulate textures.The crystallization order for these rocks is olivine±chromian spinel→clinopyroxene→plagioclase→orthopyroxene→amphibole.The presence of primary magmatic amphiboles in the cumulate rocks shows that the parent magma evolved under hydrous conditions.Geochemically,the studied rock units are characterized by low TiO2(0.18-0.57 wt.%),P2 O5(<0.05 wt.%),K2 O(0.01-0.51 wt.%)and total alkali contents(0.12-3.04 wt.%).They indicate fractionated trends in the chondrite-normalized rare earth element(REE)plots and multi-element diagrams(spider diagrams).The general trend of the spider diagrams exhibit slight enrichment in large ion lithophile elements(LILEs)relative to high field strength elements(HFSEs)and positive anomalies in Sr,Pb and Eu and negative anomalies in Zr and Nb relative to the adjacent elements.The REE plots of these rocks display increasing trend from La to Sm,positive Eu anomaly(Eu/Eu*=1.06-1.54)and an almost flat pattern from medium REE(MREE)to heavy REE(HREE)region[(Gd/Yb)N=1-1.17].Moreover,clinopyroxenes from the cumulate rocks have low REE contents and show marked depletion in light REE(LREE)compared to MREE and HREE[(La/Sm)N=0.10-0.27 and(La/Yb)N=0.08-0.22].The composition of calculated melts in equilibrium with the clinopyroxenes from less evolved cumulate samples are closely similar to island arc tholeiitic(IAT)magmas.Modal mineralogy,geochemical features and REE modeling indicate that Sabzevar cumulate rocks were formed by crystal accumulation from a hydrous depleted basaltic melt with IAT affinity.This melt has been produced by moderate to high degree(~15%)of partial melting a depleted mantle source,which partially underwent metasomatic enrichment from subducted slab components in an intra-oceanic arc setting. 展开更多
关键词 PETROLOGY GEOCHEMISTRY cumulate rocks Sabzevar ophiolite Supra-subduction zone Iran
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Cognate Mafic Enclaves Formed by Cumulated Mush Convection in a Granitic Magma Chamber:Evidence from Mineral Chemistry of the Triassic Zhashui Pluton,Qinling Orogen
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作者 ZHANG Hongbing ZHOU Xuchen +2 位作者 LAI Shaocong ZHANG Hua QIN Jiangfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第6期1479-1488,共10页
Mafic enclaves in granites are generally considered to represent coeval mafic melts that derived from metasomatized mantle,which can provide valuable information about crust-mantle interaction.Exploring the genetic li... Mafic enclaves in granites are generally considered to represent coeval mafic melts that derived from metasomatized mantle,which can provide valuable information about crust-mantle interaction.Exploring the genetic links between the mafic enclaves and their host monzogranite from the Triassic Zhashui Pluton,Qinling orogenic belt.The enclaves(220±4.6 Ma)and the monzogranite(220±2.8 Ma)display identical zircon U-Pb ages,and they also share similar trace element and zircon Lu-Hf isotopes,indicating a cognate source.The monzogranite displays zirconεHf(t)values of−0.99 to+1.98,while the mafic enclaves show similar values of−0.45 to+3.26;however,differences in mineral chemistry reveal different crystallization conditions.The amphibole from the mafic enclaves has higher temperature and pressure(757℃;2.65 kbar)compared to those of the host monzogranite(733℃;1.96 kbar),suggesting that mafic minerals in the enclaves crystallized at an early stage.Moreover,apatite in the mafic enclaves displays slightly higher volatile contents(0.72 wt%)than those of the monzogranite(0.66 wt%),indicating a volatile-rich condition.These results suggest that the mafic enclaves represent early hydrous mafic cumulates in the granitic chamber,and subsequent magma convection would have led to the formation of the mafic enclaves. 展开更多
关键词 mafic enclaves granitic chamber mafic cumulate CONVECTION Qinling or
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Late Triassic Intraoceanic Arc Aystem within Neotethys: Evidence from Cumulate Hornblende Gabbro in Gangdese Belt, South Tibet
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作者 MA Xuxuan YI Zhiyu XU Zhiqin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期21-,共1页
The Neotethys plays an important role in shaping the Gangdese magmatic belt,southern Tibet.However,the initial time of spreading and subduction of the Neotethys remains contentious.In this study,a suite of late Triass... The Neotethys plays an important role in shaping the Gangdese magmatic belt,southern Tibet.However,the initial time of spreading and subduction of the Neotethys remains contentious.In this study,a suite of late Triassic cumulate hornblende gabbro was identified in the southern margin of the Gangdese magmatic belt.The gabbro exhibits cumulate structure,with hornblende and plagioclase as the primary mineral phases.Isotopic data indicate a hydrous magma source derived from a depleted mantle wedge that has been modified by slab dehydration.Geochemical discriminations suggest that the gabbro was formed in an intraoceanic arc setting,with crystallization ages of ca.220-213 Ma.Hornblende,hornblendelagioclase and ilmenite thermometers reveal that the crystallization temperature of 900-750°C for the gabbro.Hornblende and hornblende-plagioclase geobarometers yield an emplacement depth at ca.14.5-19.5 km.This gabbro constitutes a line of evidence for an intraoceanic arc magmatism that is coeval with the counterparts in the southern Turkey,revealing an intraoceanic subduction system within the Neotethys from west to east in the Late Triassic and that the oceanization of the Neotethys was much earlier than previous expectation. 展开更多
关键词 Evidence from cumulate Hornblende Gabbro in Gangdese Belt Late Triassic Intraoceanic Arc Aystem within Neotethys South Tibet
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Accumulated damage failure mechanism of anchoring structures under cyclic impact disturbance 被引量:2
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作者 Peng Wang Nong Zhang +7 位作者 Jiaguang Kan Qun Wei Zhengzheng Xie Aoran Li Zhe He Jinghua Qi Xingliang Xu Changrui Duan 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第12期1693-1709,共17页
Cyclic impact induces ongoing fatigue damage and performance degradation in anchoring structures,ser-ving as a critical factor leading to the instability of deep roadways.This paper takes the intrinsic spatio-temporal... Cyclic impact induces ongoing fatigue damage and performance degradation in anchoring structures,ser-ving as a critical factor leading to the instability of deep roadways.This paper takes the intrinsic spatio-temporal relationship of macro-microscopic cumulative damage in anchoring structures as the main thread,revealing the mechanism of bearing capacity degradation and progressive instability of anchoring structure under cyclic impact.Firstly,a set of impact test devices and methods for the prestressed solid anchor bolt anchoring structure were developed,effectively replicating the cyclic impact stress paths in situ.Secondly,cyclic impact anchoring structure tests and simulations were conducted,which clarifies the damage evolution mechanism of the anchoring structure.Prestress loss follows a cubic decay func-tion as the number of impacts increases.Under the same impact energy and pretension force,the impact resistance cycles of extended anchoring and full-length anchoring were increased by 186.7%and 280%,respectively,compared to end anchoring.The rate of internal damage accumulation is positively corre-lated with impact energy and negatively correlated with anchorage length.Internal tensile cracks account for approximately 85%.Stress transmission follows a fluctuating pattern.Compared to the extended anchoring,the maximum vibration velocity of the exposed end particles in the full-length anchoring was reduced by 59.31%.Damage evolution exhibits a pronounced cumulative mutation effect.Then,a three-media,two-interface mechanical model of the anchoring structure was constructed.It has been clarified that the compressive stress,tensile stress,and oscillation effect arising from rapid transi-tions between compression and tension are the primary internal factors responsible for the degradation of the anchoring structure’s bearing capacity.Finally,the progressive instability mechanism of the anchoring structure under cyclic impact was elucidated.The mutual feedback and superposition of media rupture,interface debonding,and bearing capacity degradation result in overall failure.The failure pro-cess involves stages dominated by oscillation-compression,tensile stress,and compression failure.A tar-geted control strategy was further proposed.This provides a reference for maintaining the long-term stability of deep roadways under dynamic impact loads. 展开更多
关键词 Cyclic impact Anchoring structure Cumulative damage Bearing capacity degradation Progressive instability
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Cumulate complex xenoliths in the Early Mesozoic in eastern Inner Mongolia 被引量:21
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作者 Ji’an Shao Qingjun Han +1 位作者 Luqiao Zhang Baolei Mu 《Chinese Science Bulletin》 SCIE EI CAS 1999年第14期1272-1279,共8页
Mafic xenoliths occur in Mesozoic diorites from nine localities in eastern Inner Mongolia from the Da Hinggan Mrs. to Huabei craton. Their petrologic and geochemical features suggest that they are an intact suite of c... Mafic xenoliths occur in Mesozoic diorites from nine localities in eastern Inner Mongolia from the Da Hinggan Mrs. to Huabei craton. Their petrologic and geochemical features suggest that they are an intact suite of cumulate complex whose mineral assemblages contain typical patent mantle metasomatism minerals such as pargosite, phlogopite and apatite. Their REEs and trace element characteristics suggest a comagmatic relationship in these cumulates with different compositions. Isotopic dating of the xenoliths indicates that they are products of the mantle magmatic underplating in the Early Mesozoic (237—224 Ma), and they may provide direct evidence for the crust-mantle interaction and vertical accretion of continental crust under a background of the mantle upwelling in the Early Mesozoic in Huabei region. 展开更多
关键词 cumulate underplating. CRUST-MANTLE interaction Early Mesozoic. EASTERN Inner Mongolia.
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SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang,northern Tibetan Plateau 被引量:37
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作者 ZHAI QingGuo WANG Jun +1 位作者 LI Cai SU Li 《Science China Earth Sciences》 SCIE EI CAS 2010年第5期657-664,共8页
Metabasites consisting of metamorphic ultra-mafic rocks,cumulate gabbro,gabbro(diabase),basalt,and plagiogranite are exposed at the Taoxinghu area in central Qiangtang,northern Tibetan Plateau.Zircon SHRIMP U-Pb datin... Metabasites consisting of metamorphic ultra-mafic rocks,cumulate gabbro,gabbro(diabase),basalt,and plagiogranite are exposed at the Taoxinghu area in central Qiangtang,northern Tibetan Plateau.Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma,which is the oldest and most reliable magmatic age in this area.Zircon 176Hf/177Hf ratios range from 0.282615 to 0.282657,withεHf(t)values of 5.02±0.28,indicating that the cumulate gabbro was mainly derived from the depleted mantle.In addition,geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts(MORB).The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the"Central Uplift"of the Qiangtang,northern Tibetan Plateau. 展开更多
关键词 QIANGTANG cumulate gabbro SHRIMP dating Hf isotope
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Long-term Cumulative Depressive Symptoms and Incident Cardiovascular Disease in Middle-aged and Older Population:Two Cohort Studies
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作者 Fangfei You Yining Gao +11 位作者 Wenfang Zhong Zhihao Li Jian Gao Dong Shen Xiaomeng Wang Weiqi Song Qi Fu Haoyu Yan Jiahao Xie Huan Chen Hao Yan Chen Mao 《Biomedical and Environmental Sciences》 2026年第1期15-25,共11页
Objective Elevated depressive symptoms are well-documented among geriatric adults with cardiovascular disease(CVD);however,few studies have accounted for long-term cumulative depressive symptom exposure.This study det... Objective Elevated depressive symptoms are well-documented among geriatric adults with cardiovascular disease(CVD);however,few studies have accounted for long-term cumulative depressive symptom exposure.This study determined the relationship between cumulative depressive symptoms and CVD.Methods Individual participant data were obtained from the China Health and Retirement Longitudinal Study(CHARLS)and Health and Retirement Study(HRS).Eligible participants had access to assessment information on depressive symptoms and had no history of CVD at baseline.Long-term cumulative depressive symptoms were estimated by calculating the area under the curve based on the Center for Epidemiological Studies Depression Scale.Results Herein,8,861 participants from CHARLS(mean age:58.58 years;male:48.6%)and 7,284 from HRS(60.94 years;35.0%)were enrolled.The median follow-up period was 5 years for the CHARLS and10 years for the HRS.Compared with the first quartile of cumulative depressive symptoms,the HRs(95%CI)in the fourth quartile were 1.73(1.48,2.02)for predicting CVD(P<0.001),1.83(1.52,2.19)for heart disease(P<0.001),1.53(95%CI:1.17,1.99)for stroke(P=0.002)in CHARLS.For HRS,the HRs(95%CI)were 1.41(95%CI:1.27,1.57;P<0.001),1.42(95%CI:1.26,1.59;P<0.001),and 1.30(95%CI:1.06,1.58;P=0.010)respectively.Strong dose-response relationships were observed,with similar results for the two cohorts.Conclusion Long-term cumulative depressive symptoms were significantly associated with incident CVD in middle-aged and older adults,providing insights into controlling long-term depressive symptoms to improve this cohort's health. 展开更多
关键词 Cumulative depressive symptom CVD COHORT CHARLS HRS
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Characterizing the dynamic behavior and progressive damage evolution of carbonaceous slate under cyclic impact loading
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作者 Zhuang Li Nuwen Xu +4 位作者 Zhiqiang Sun Huabo Xiao Can Yang Huaizhong Liu Biao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1060-1072,共13页
Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical... Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis. 展开更多
关键词 Split Hopkinson pressure bar Cyclic impact Dynamic behavior Cumulative damage MICROSTRUCTURE
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Differential roles of EA-TRAPed cells in the anterior cingulate cortex across various intervention times in inflammatory pain
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作者 Zi Guo Ru Ye +6 位作者 Lu Guan Wei He Shuang Qiu Xiaomei Shao Junfan Fang Jianqiao Fang Junying Du 《Animal Models and Experimental Medicine》 2026年第2期329-343,共15页
Background:The analgesic effects of multiple electroacupuncture(EA)sessions and single EA sessions differ significantly in pain management.Area 24b(A24b)of the anterior cingulate cortex(ACC)is crucial in pain processi... Background:The analgesic effects of multiple electroacupuncture(EA)sessions and single EA sessions differ significantly in pain management.Area 24b(A24b)of the anterior cingulate cortex(ACC)is crucial in pain processing.EA relieves pain by targeting and modulating the neuronal activity within this subregion.However,whether the cumulative effect of EA antinociception is connected to A24b mechanisms has remained unclear.Methods:In our study,we used the Complete Freund's Adjuvant(CFA)model to induce inflammatory pain and the Spared Nerve Injury(SNI)model to induce neuropathic pain,and adult male C57BL/6,FosTRAP,and FosTRAP:Ai9 mice were used as experimental subjects to investigate the cumulative effect of EA antinociception and whether multiple EA sessions and a single EA session regulate different neuronal populations in the A24b.Results:We observed that EA effectively alleviated pain in mice,with three EA sessions yielding superior analgesic effects compared to a single session.Using chemical genetics combined with FosCreER technology to activate EA-TRAPed cells in the A24b,we found that pain relief was more pronounced with three EA sessions.Moreover,chemogenetic inhibition of EA-TRAPed cells in the A24b reversed the analgesic effects of a single EA session but not those of three EA sessions.Fluorescent in situ hybridization results indicated that three EA sessions significantly increased the number of GABAergic neurons in the A24b compared with a single session.Additionally,retrograde tracing revealed that the A24b circuit that monosynaptically innervates EA-TRAPed cells included projections from the central lateral nucleus(CL),lateral mediodorsal thalamic nucleus(MDL),lateral habenula(LHb),dorsal raphe nucleus(DR),caudal linear nucleus of the raphe(CLi),dorsal tuberomamillary nucleus(DTM),periventricular hypothalamic nucleus(Pe)and hippocampal fields CA1,CA2,and CA3.These findings suggest that multiple EA sessions and single EA sessions activated different neuronal populations in the A24b.The enhanced analgesic effect of multiple EA sessions may be attributed to an increase in the proportion of GABAergic neurons within the A24b.Conclusions:Multiple and single EA sessions recruit distinct neuronal populations in A24b,with the stronger analgesic effect of repeated EA linked to a higher proportion of GABAergic neurons in this region. 展开更多
关键词 anterior cingulate cortex cumulative effect ELECTROACUPUNCTURE GABAergic neurons inflammatory pain
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Bayesian neural network evaluation method on the neutron-induced fission product yields of^(232)Th
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作者 Chun-Yuan Qiao Ya-Xuan Wang +2 位作者 Chun-Wang Ma Jun-Chen Pei Yong-Jing Chen 《Nuclear Science and Techniques》 2026年第3期132-142,共11页
Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distribu... Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distributions over a wide range of neutron energies remains a challenge.In this study,a Bayesian neural network model was developed to predict the independent(IND)and cumulative fission yields of^(232)Th under neutron irradiation at various incident energies.To address the limited availability of experimental data for the analysis of IND mass distributions,we substituted mass-number-based yields with the yields of specific isotopes.Furthermore,physical phenomena or quantities,such as the odd-even effect and isospin,were introduced as constraints to enhance the physical consistency of the predictions.The impact of these constraints was evaluated using mass-chain yield distributions and their dependence on energy.Incorporating physical constraints significantly improves the prediction accuracy,yielding more reliable and physically meaningful fission yield data for nuclear physics and reactor design applications. 展开更多
关键词 Bayesian neural network ^(232)Th Independent fission yield Cumulative fission yield Odd–even effect ISOSPIN
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Geologic hazard susceptibility assessment based on statistical optimization and machine learning:A case study of the Loess Plateau,Shaanxi Province,northwestern China
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作者 Hao Cheng Zhen-kai Zhang +5 位作者 Zeng-lin Hong Wen-long Zhang Hong-quan Teng Shuai Yang Zi-yao Wang Yu-xuan Dong 《China Geology》 2026年第1期136-151,共16页
This study developed a modeling methodology for statistical optimization-based geologic hazard susceptibility assessment,aiming to enhance the comprehensive performance and classification accuracy of the assessment mo... This study developed a modeling methodology for statistical optimization-based geologic hazard susceptibility assessment,aiming to enhance the comprehensive performance and classification accuracy of the assessment models.First,the cumulative probability method revealed that a low probability(15%)of geologic hazards between any two geologic hazard points occurred outside a buffer zone with a radius of 2297 m(i.e.,the distance threshold).The training dataset was established,consisting of negative samples(non-hazard points)randomly generated based on the distance threshold,positive samples(i.e.,historical hazards),and 13 conditioning factors.Then,models were built using five machine learning algorithms,namely random forest(RF),gradient boosting decision tree(GBDT),naive Bayes(NB),logistic regression(LR),and support vector machine(SVM).The comprehensive performance of the models was assessed using the area under the receiver operating characteristic curve(AUC)and overall accuracy(OA)as indicators,revealing that RF exhibited the best performance,with OA and AUC values of 2.7127 and 0.981,respectively.Furthermore,the machine learning models constructed by considering the distance threshold outperformed those built using the unoptimized dataset.The characteristic factors were ranked using the mutual information method,with their scores decreasing in the order of rainfall(0.1616),altitude(0.06),normalized difference vegetation index(NDVI;0.04),and distance from roads(0.03).Finally,the geologic hazard susceptibility classification was assessed using the natural breaks method combined with a clustering algorithm.The results indicate that the clustering algorithm exhibited higher classification accuracy than the natural breaks method.The findings of this study demonstrate that the proposed model optimization scheme can provide a scientific basis for the prevention and control of geologic hazards. 展开更多
关键词 COLLAPSE LANDSLIDE Debris flow Geologic hazard susceptibility assessment Machine learning RF-GBDT-NB-LR-SVM Cumulative probability Cluster analysis Loess Plateau Geologic hazard prevention and control Geological survey engineering
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Cumulative effects of stress-sensitivity factors on depressive symptoms and suicide risk:A prospective study 被引量:1
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作者 Xue-Mei Qin Meng-Qi Xu +20 位作者 Ya-Qi Qin Fang-Zhou Shao Mo-Han Ma Wen-Wen Ou Guan-Yi Lv Qian-QianZhang Wen-Tao Chen Xiao-Tian Zhao Ao-Qian Deng Jin-Tao Xiong Ling-Si Zeng Yi-Lin Peng Mei Huang Shu-Yin Xu Mei Liao Li Zhang Ling-Jiang Li Yu-Meng Ju Jin Liu Bang-Shan Liu Yan Zhang 《World Journal of Psychiatry》 2025年第2期173-185,共13页
BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity va... BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity variables affect MDD.We hypothesize that high-level trait-and state-related stress-sensitivity factors may have different cumulative effects on the clinical symptoms and follow-up outcomes of MDD.AIM To investigate how stress-sensitivity factors added up and affected MDD clinical symptoms and follow-up results.METHODS In this prospective study,281 MDD patients were enrolled from a tertiary care setting.High-level stress-sensitivity factors were classified as trait anxiety,state anxiety,perceived stress,and neuroticism,with a total score in the top quartile of the research cohort.The cumulative effects of stress-sensitivity factors on cognitive dysfunction,disability and functional impairment,suicide risk,and depressive and anxiety symptoms were examined using an analysis of variance with linear trend analysis.Correlations were investigated further using multiple regression analysis.RESULTS Regarding high-level stress-sensitivity factors,53.40%of patients had at least one at baseline,and 29.61%had two or more.Four high-level stress-sensitivity components had significant cumulative impacts on MDD symptoms at baseline(all P<0.001).Perceived stress predicted the greatest effect sizes of state-related factors on depressive symptoms(partialη^(2)=0.153;standardizedβ=0.195;P<0.05).The follow-up outcomes were significantly impacted only by the high-level trait-related components,mainly when it came to depressive symptoms and suicide risk,which were predicted by trait anxiety and neuroticism,respectively(partialη^(2)=0.204 and 0.156;standardizedβ=0.247 and 0.392;P<0.05).CONCLUSION To enhance outcomes of MDD and lower the suicide risk,screening for stress-sensitivity factors and considering multifaceted measures,mainly focusing on trait-related ones,should be addressed clinically. 展开更多
关键词 Major depressive disorder Stress sensitivity Depressive symptoms Suicide risk Cumulative effect
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Damage prediction of rear plate in Whipple shields based on machine learning method 被引量:1
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作者 Chenyang Wu Xiangbiao Liao +1 位作者 Lvtan Chen Xiaowei Chen 《Defence Technology(防务技术)》 2025年第8期52-68,共17页
A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,wh... A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,which reduces the risk of penetrating the bulkhead.In the realm of hypervelocity impact,strain rate(>10^(5)s^(-1))effects are negligible,and fluid dynamics is employed to describe the impact process.Efficient numerical tools for precisely predicting the damage degree can greatly accelerate the design and optimization of advanced protective structures.Current hypervelocity impact research primarily focuses on the interaction between projectile and front plate and the movement of debris cloud.However,the damage mechanism of debris cloud impacts on rear plates-the critical threat component-remains underexplored owing to complex multi-physics processes and prohibitive computational costs.Existing approaches,ranging from semi-empirical equations to a machine learningbased ballistic limit prediction method,are constrained to binary penetration classification.Alternatively,the uneven data from experiments and simulations caused these methods to be ineffective when the projectile has irregular shapes and complicate flight attitude.Therefore,it is urgent to develop a new damage prediction method for predicting the rear plate damage,which can help to gain a deeper understanding of the damage mechanism.In this study,a machine learning(ML)method is developed to predict the damage distribution in the rear plate.Based on the unit velocity space,the discretized information of debris cloud and rear plate damage from rare simulation cases is used as input data for training the ML models,while the generalization ability for damage distribution prediction is tested by other simulation cases with different attack angles.The results demonstrate that the training and prediction accuracies using the Random Forest(RF)algorithm significantly surpass those using Artificial Neural Networks(ANNs)and Support Vector Machine(SVM).The RF-based model effectively identifies damage features in sparsely distributed debris cloud and cumulative effect.This study establishes an expandable new dataset that accommodates additional parameters to improve the prediction accuracy.Results demonstrate the model's ability to overcome data imbalance limitations through debris cloud features,enabling rapid and accurate rear plate damage prediction across wider scenarios with minimal data requirements. 展开更多
关键词 Damage prediction of rear plate Cumulative effect of debris cloud Whipple shield Machine learning Random forest
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Corrections to scaling in the 2D φ^(4) model:Monte Carlo results and some related problems
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作者 J.Kaupuzs R.V.N.Melnik 《Communications in Theoretical Physics》 2025年第6期210-222,共13页
Monte Carlo(MC) simulations have been performed to refine the estimation of the correction-toscaling exponent ω in the 2D φ^(4)model,which belongs to one of the most fundamental universality classes.If corrections h... Monte Carlo(MC) simulations have been performed to refine the estimation of the correction-toscaling exponent ω in the 2D φ^(4)model,which belongs to one of the most fundamental universality classes.If corrections have the form ∝ L^(-ω),then we find ω=1.546(30) andω=1.509(14) as the best estimates.These are obtained from the finite-size scaling of the susceptibility data in the range of linear lattice sizes L ∈[128,2048] at the critical value of the Binder cumulant and from the scaling of the corresponding pseudocritical couplings within L∈[64,2048].These values agree with several other MC estimates at the assumption of the power-law corrections and are comparable with the known results of the ε-expansion.In addition,we have tested the consistency with the scaling corrections of the form ∝ L^(-4/3),∝L^(-4/3)In L and ∝L^(-4/3)/ln L,which might be expected from some considerations of the renormalization group and Coulomb gas model.The latter option is consistent with our MC data.Our MC results served as a basis for a critical reconsideration of some earlier theoretical conjectures and scaling assumptions.In particular,we have corrected and refined our previous analysis by grouping Feynman diagrams.The renewed analysis gives ω≈4-d-2η as some approximation for spatial dimensions d <4,or ω≈1.5 in two dimensions. 展开更多
关键词 Monte Carlo simulations universality classes linear lattice sizes Binder cumulant corrections scaling scaling corresponding ps MODEL binder cumulant
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Methods of cumulative quantum mechanics for describing the interaction of electromagnetic fields with matter in Vysikaylo large standing nanoscale excitons:Hydrogen-like atoms,molecules,surfaces,and twinkling crystals
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作者 Philipp I.Vysikaylo 《Nanotechnology and Precision Engineering》 2025年第4期127-142,共16页
Using cumulative quantum mechanics(CQM)and the method of generalized mathematical transfer(MGMT),we analytically study quantum nanometer cumulative-dissipative structures(CDS)and the forces arising within them,which f... Using cumulative quantum mechanics(CQM)and the method of generalized mathematical transfer(MGMT),we analytically study quantum nanometer cumulative-dissipative structures(CDS)and the forces arising within them,which focus nanostructures into regular,fractalized systems—cumulative-dissipative standing hydrogen-like excitons(atoms,molecules,lines,surfaces)and flickering crystals we discovered for the first time.(1)We demonstrate the formation of Vysikaylo standing excitons on permittivity[ε(r)]inhomogeneities in diamond in the nanoscale regions of foreign atoms.(2)For the first time,we solve the problem of measuringε(r)profiles in inhomogeneous nanoscale structures using Raman spectra(RS)[with an accuracy of up to 99.9%forε(r)and a step of up to 0.3 nm depending on the distance from the impurity atom(boron)].(3)Using our theory of Vysikaylo standing excitons,we explain the experimental observation of the degeneracy of electron spectra in standing excitons with respect to the principal quantum number n and n−1/2.By comparing the theory and experimental observations of RS in diamonds doped with boron,we solve the problem(that we formulated previously)between the de Broglie hypothesis and the classical new quantum mechanics of Dirac(which limits the-functions,or prohibits symmetric de Broglie half-waves in spherically and cylindrically symmetric quantum resonators)in favor of the de Broglie hypothesis.Based on the works of Wannier and Mott,we refine the definition of the permittivity of nanocrystals as a coefficient in electric potentials[U(r)→ε(r)U(r)]rather than electric fields[D(r)=ε(r)E(r)].We construct the most complete theory of the chemical doping of crystals(using the example of group IV crystals doped with group III and V atoms).For the first time,we raise the question of the quantum cleaning of crystals or the accumulation of dopant atoms. 展开更多
关键词 Physical and chemical doping of nanostructured materials Vysikaylo cumulative-dissipative structures Flickering hyperatoms MOLECULES and crystal lattices Cumulative quantum mechanics Cumulation of de Broglie waves Unlimited cumulation of de Broglie waveψ_(n−1/2)-functions Points lines planes of cumulation-libration
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Characterization of combined blast-and fragments-induced synergetic damage in polyurea coated liquid-filled container
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作者 Chen Tao Chong Ji +3 位作者 Xin Wang Juan Gu Yuting Wang Changxiao Zhao 《Defence Technology(防务技术)》 2025年第1期201-224,共24页
Liquid-filled containers(LFC)are widely used to store and transport petroleum,chemical reagents,and other resources.As an important target of military strikes and terrorist bombings,LFC are vulnerable to blast waves a... Liquid-filled containers(LFC)are widely used to store and transport petroleum,chemical reagents,and other resources.As an important target of military strikes and terrorist bombings,LFC are vulnerable to blast waves and fragments.To explore the protective effect of polyurea elastomer on LFC,the damage characteristics of polyurea coated liquid-filled container(PLFC)under the combined loading of blast shock wave and fragments were studied experimentally.The microstructure of the polyurea layer was observed by scanning electron microscopy,and the fracture and self-healing phenomena were analyzed.The simulation approach was used to explain the combined blast-and fragments-induced on the PLFC in detail.Finally,the effects of shock wave and fragment alone and in combination on the damage of PLFC were comprehensively compared.Results showed that the polyurea reduces the perforation rate of the fragment to the LFC,and the self-healing phenomenon could also reduce the liquid loss rate inside the container.The polyurea reduces the degree of depression in the center of the LFC,resulting in a decrease in the distance between adjacent fragments penetrating the LFC,and an increase in the probability of transfixion and fracture between holes.Under the close-in blast,the detonation shock wave reached the LFC before the fragment.Polyurea does not all have an enhanced effect on the protection of LFC.The presence of internal water enhances the anti-blast performance of the container,and the hydrodynamic ram(HRAM)formed by the fragment impacting the water aggravated the plastic deformation of the container.The combined action has an enhancement effect on the deformation of the LFC.The depth of the container depression was 27%higher than that of the blast shock wave alone;thus,it cannot be simply summarized as linear superposition. 展开更多
关键词 POLYUREA Prefabricated fragment Liquid-filled container Hydrodynamic ram Cumulative effect
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Natural surgical risks and age distribution in Chinese patients with Peutz-Jeghers syndrome:Real-world research based on a web survey
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作者 Nian-Jun Xiao Su Liu +7 位作者 Zhe-Yi Han Tong-Zhen Zhang Zhi-Meng Jiang Tao Sun Jing Zhang Lei Wang Shou-Bin Ning Wen Li 《World Journal of Gastrointestinal Surgery》 2025年第5期239-248,共10页
BACKGROUND Complications arising from the polyps in Peutz-Jeghers syndrome(PJS)have historically been addressed through surgical treatment.Enteroscopic poly-pectomy is hypothesized to reduce the risk of surgery in PJS... BACKGROUND Complications arising from the polyps in Peutz-Jeghers syndrome(PJS)have historically been addressed through surgical treatment.Enteroscopic poly-pectomy is hypothesized to reduce the risk of surgery in PJS.However,the optimal timing for polyp screening and preventive intervention using entero-scopic polypectomy remains uncertain.This is primarily due to the extremely low incidence of the condition and the paucity of data regarding the natural risk of requiring surgery and its age distribution in PJS patients.In order to develop recommendations on the appropriate timing of polyp screening and preventive intervention in PJS,a comprehensive understanding of the natural surgical risks AIM To investigate the natural surgical risks associated with polyps in PJS and to clarify their age distribution.METHODS A web-based open survey was launched to collect information from Chinese individuals suspected of having PJS.The questionnaire was distributed to the PJS instant messaging groups using a quick response code method.The data were analyzed using descriptive statistical methods,and the cumulative incidence of surgery was calculated using the Kaplan-Meier method.RESULTS Of the 442 patients enrolled,301(68.10%)had undergone 506 surgical procedures prior to enteroscopy or the survey deadline.Among the 506 surgical procedures,388(76.68%)were performed on patients aged between 6 and 25 years.The cumulative incidence rates of the first surgical procedure at 5,10,15,20,25,and 30 years of age were 5.0%(95%confidence interval[CI]:2.9%-7.0%),20.6%(95%CI:16.6%-24.4%),40.5%(95%CI:35.5%-45.1%),58.0%(95%CI:52.7%-62.7%),72.6%(95%CI:67.3%-77.0%),and 82.4%(95%CI:77.0%-86.5%),respectively.The primary indications for the first surgical procedures were intussusception(81.40%),obstruction(13.95%),and gas-trointestinal bleeding(4.65%).The cumulative incidence rates of requiring a second surgical procedure within 1,3,5,10 and 15 years following the first surgical procedure were 3.7%(95%CI:1.5%-5.8%),12.5%(95%CI:8.6%-16.2%),20.3%(95%CI:15.6%-24.8%),37.0%(95%CI:33.1%-45.3%),54.2%(95%CI:46.8%-60.5%),respectively.Patients who underwent their first surgical procedure at the age of nine years or younger presented an elevated risk of requiring a second surgical procedure(P<0.01).CONCLUSION Chinese patients with PJS have a high natural risk of undergoing surgery.Without preventive intervention,these procedures may become necessary at an early age and may be repeated.Early screening and regular surveillance,with preventive intervention if necessary,should commence at six years of age. 展开更多
关键词 Peutz-Jeghers syndrome Web surveys INTUSSUSCEPTION Balloon-assisted enteroscopy Cumulative risk Mucocutaneous pigmentation Hamartomatous polyps
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