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Metallogenesis and ore-forming time of the Changtuxili Mn-Ag-Pb-Zn deposit in Inner Mongolia:Evidence from C-O-S isotopes and U-Pb geochronology

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Geoscience Frontiers 2020年第4期11卷 1369-1380页

作者： Kuo Zhang Ruo-Shi Jin feng-yue sun Bi-Le Li Peng He yue-Long Zhang Shuo Guo Tian-Fu Zhang College of Earth Sciences Jilin UniversityChangchun130061China Tianjin Center China Geological SurveyTianjin300170China North China Center for Geoscience Innovation Tianjin300170China Qiqihar Branch Heilongjiang Institute of Geological Survey and ResearchQiqihar150036China

This paper reports new geochronological(U-Pb) and isotope(C,O,and S) data to investigate the timing of mineralization and mode of ore genesis for the recently discovered Changtuxili Mn-Ag-Pb-Zn deposit,located on the western slopes of the southern Great Hinggan Range in NE *** mineralization is hosted by intermediate-acidic lavas and pyroclastic rocks of the Baiyingaolao *** stages of mineralization are identified:quartz-pyrite(Stage I),galena-sphalerite-tetrahedrite-rhodochrosite(Stage II),and quartz-pyrite(Stage Ⅲ).δ13C and δ18O values for carbonate from the ore vary from-8.51‰ to-4.96‰ and 3.97‰ to 15.90‰,respectively,which are indicative of a low-temperature alteration environment.δ34SV-CDT values of sulfides range from-1.77‰ to 4.16‰ and show a trend of equilibrium fractionation(δ34SPy>δ34SSp>δ34SGn).These features indicate that pyrite,sphalerite,and galena precipitated during the period of *** alteration mineral assemblage and isotope data indicate that the weakly acidic to weakly alkaline ore-forming fluid was derived largely from meteoric water and the ore-forming elements C and S originated from *** the mineralization,a geochemical barrier was formed by changes in the pH of the ore-forming fluid,leading to the precipitation of *** the basis of the mineralization characteristics,new isotope data,and comparison with adjacent deposits,we propose that the Changtuxili Mn-Ag-Pb-Zn deposit is an intermediate-to lowsulfidation epithermal deposit whose formation was controlled by fractures and variability in the pH of the oreforming *** surrounding volcanic rocks yield zircon U-Pb ages of 160-146 Ma(Late Jurassic),indicating that the mineralization is younger than 146 Ma.

关键词： Inner Mongolia Changtuxili Mn-Ag-Pb-Zn deposit C-O-S isotope geochemistry Zircon U-Pb age Intermediate-to low-sulfidation epithermal deposit

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Age and petrogenesis of late Mesozoic intrusions in the Huoluotai porphyry Cu-(Mo)deposit,northeast China:Implications for regional tectonic evolution

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Geoscience Frontiers 2022年第2期13卷 311-332页

作者： Yong-gang sun Bi-le Li Zhong-hai Zhao feng-yue sun Qing-feng Ding Xu-sheng Chen Jie-biao Li Ye Qian Yu-jin Li College of Earth Sciences Jilin UniversityChangchun 130061China College of Mining Liaoning Technical UniversityFuxin 123000China Qiqihaer Institute of Geological Exploration Heilongjiang 161006China School of Environment Harbin Institute of TechnologyHarbin 150090China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and ResourcesChangchun 130061China

Multi-stage igneous rocks developed in the recently discovered Huoluotai Cu-(Mo)deposit provide new insights into the controversial late Mesozoic geodynamic evolution of the northern segment of the Great Xing’an Range(NSGXR).Zircon U-Pb dating suggests that the monzogranite,ore-bearing granodiorite porphyry,diorite porphyry,and granite porphyry in the deposit were emplaced at 179.5±1.6,148.9±0.9,146.1±1.3,and 142.2±1.5 Ma,*** Re-Os dating of molybdenite yielded an isochron age of 146.9±2.3 Ma(MSWD=0.27).The Jurassic adakitic monzogranite and granodiorite porphyry are characterized by high SiO_(2)and Na_(2)O contents,low K_(2)O/Na_(2)O ratios,low Mg O,Cr,and Ni contents,low zirconεHf(t)values relative to depleted mantle,and relatively high Th *** were produced by partial melting of a subducted oceanic slab,with involvement of marine sediments in the magma source and limited interaction with mantle peridotites during magma *** Late Jurassic diorite porphyry is characterized by moderate SiO_(2) contents,high Mg O,Cr,and Ni contents,and positive dominatedεHf(t)values,indicating it was produced by partial melting of a subduction-modified lithospheric mantle wedge and underwent limited crustal contamination during magma *** early Early Cretaceous adakitic granite porphyry shows high SiO_(2) and K_(2)O contents and K_(2)O/Na_(2)O ratios,low Mg O,Cr,and Ni contents,enriched Sr-Nd isotopic compositions,and slightly positive zirconεHf(t)values,suggesting it was produced by partial melting of thickened mafic lower *** NSGXR experienced a tectonic history that involved flat-slab subduction(200-160 Ma),and tearing and collapse(150-145 Ma)of the Mongol-Okhotsk oceanic *** period of magmatic quiescence from ca.160 to 150 Ma was a response to flat-slab subduction of the Mongol-Okhotsk oceanic *** thickening in the NSGXR(145-133 Ma)was due to the collision between the Amuria Block and the Siberian Craton.

关键词： Geochemistry Zircon U-Pb dating Huoluotai Cu-(Mo)deposit Flat-slab subduction Mongol-Okhotsk Ocean

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Dissociation of gas hydrates by hydrocarbon migration and accumulation-derived slope failures:An example from the South China Sea

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Geoscience Frontiers 2022年第2期13卷 295-310页

作者： Zhi-feng Wan Wei Zhang Chong Ma Jin-Qiang Liang Ang Li Da-Jiang Meng Wei Huang Cheng-Zhi Yang Jin-feng Zhang yue-feng sun School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Gas Hydrate Engineering Technology Center Guangzhou Marine Geological SurveyChina Geological SurveyMinistry of Natural ResourcesGuangzhou 510075China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Mathematics and Physics China University of Geosciences(Wuhan)Wuhan 430074China Qingdao Institute of Marine Geology Qingdao 266071China Department of Geology&Geophysics Texas A&M UniversityCollege Station 77843-3115United States

The mechanism of slope failure associated with overpressure that is caused by hydrocarbon migration and accumulation remains ***-resolution seismic data and gas hydrate drilling data collected from the Shenhu gas hydrate field(site SH5)offer a valuable opportunity to study the relations between submarine slope failure and hydrocarbon accumulation and flow that is associated with a~2 kmdiameter gas chimney developed beneath site SH5 where none gas hydrates had been recovered by drilling and sampling despite the presence of distinct bottom simulating reflectors(BSRs)and favorable gas hydrate *** mechanism of submarine slope failure resulted from buoyancy extrusion and seepage-derived deformation which were caused by overpressure from a~1100 m-high gas column in a gas chimney was studied via numerical ***~9.55 MPa overpressure caused by hydrocarbons that migrated through the gas chimney and then accumulated beneath subsurface gas hydratebearing impermeable *** may have resulted in a submarine slope failure,which disequilibrated the gas hydrate-bearing zone and completely decomposed the gas hydrate once precipitated at site *** the gas hydrate decomposition,the largely impermeable sediments overlying the gas chimney may have undergone a major upward deformation due to the buoyancy extrusion of the overpressure in the gas chimney,and slope failure was initiated from plastic strain of the sediments and reduced internal *** failure subsequently resulted in partial gas hydrate decomposition and sediment permeability *** pressurized gas in the gas chimney may have diffused into the overlying sediments controlled by seepage-derived deformation,causing an effective stress reduction at the base of the sediments and significant plastic *** may have formed a new cycle of submarine slope failure and finally the total gas hydrate *** modeling results of buoyancy extrusion and seepage-deri

关键词： Natural gas hydrate Submarine slope failure Gas chimney Buoyancy extrusion Seepage-derived deformation Shenhu area Northern South China Sea

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Risk factors associated with postoperative hospital stay after pancreaticoduodenectomy： a retrospective study

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Chinese Medical Journal 2013年第19期126卷 3685-3689页

作者： XIE Yi-bin WANG Cheng-feng ZHAO Dong-bing SHAN Yi BAI Xiao-feng sun yue-min CHEN Ying-tai ZHAO Ping TIAN Yan-tao Department of Abdominal Surgical Oncology Cancer HospitalChinese Academy of Medical Sciences Peking Union MedicalCollege Beijing 100021 China

Background Postoperative hospital stay after pancreaticoduodenectomy （PD） is relatively longer than after other gastrointestinal *** aim of the current study was to investigate the risk factors associated with prolonged hospital stay after *** Patients who had PD at the Cancer Hospital of Chinese Academy of Medical Sciences between December 2008 and November 2012 were selected for this retrospective *** and pathological data were collected and *** primary outcome was postoperative length of *** discharge or recovery was defined as a postoperative hospital stay of no more than 10 days; otherwise it was defined as delayed discharge or recovery （including hospital death）.Results Atotal of 152 patients were enrolled in the present *** hospital stay was （19.7±7.7） days （range 7-57）.Of the 152 patients,67 were discharged within the normal time and 85 had delayed *** complications occurred in 62.5% （95/152）,and the mortality rate was 3.29% （5/152）.Multiple regression analysis showed that delayed discharge was significantly associated with postoperative complications （adjusted odds ratio （OR） 10.40,95% confidence interval （CI） 3.58-30.22）,age （adjusted OR 4.09,95% CI 1.16-14.39）,body mass index （BMI）（adjusted OR 4.40,95% CI 1.19-16.23）,surgical procedure （adjusted OR 26.14,95% CI 4.94-153.19）,blood transfusion （adjusted OR 7.68,95% Cl 2.09-28.27）,and fluid input （adjusted OR 3.47,95% CI 1.24-11.57）.Conclusions Postoperative complications increase the time to postoperative hospital *** length of hospital stay after PD is also associated with age,BMI,blood transfusion,surgical procedure,and fluid *** studies with more patients are needed in future.

关键词： length of stay pancreaticoduodenectomy postoperative period risk factors

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CORRELATION OF DOLOMITE OCCURRENCE WITH SEDIMENTATION RATE CHANGE

CORRELATION OF DOLOMITE OCCURRENCE WITH SEDIMENTATION RATE C...

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理论与应用地球物理研讨会

作者： yue-feng sun Lamont-Doherty Earth Observatory Columbia University, Palisades, NY 10964, USA

＜正＞ During the expedition on board the R/V JOIDES Resolution, Ocean Drilling Program （ODP） Leg 186, it is discovered that there exists several thin layers of dolomitic rocks imbedded in otherwise uniform diatomaceous silty sediments and claystone. The thickness of the dolomite layers ranges from 0.5 m to 2 m as estimated from the in-situ log data. In this paper we demonstrate that these thin dolomite layers can have profound influence to alter seismic appearance, even on conventional low-frequency seismic data. Using advanced amplitude-preserving high resolution enhancement techniques, a high-resolution dolomite imaging profile is obtained crossing one of the drill site. We provide the first geophysical evidence of large-scale dolomite occurrence in the dynamic forearc basin developed in the deep-sea terrace on the landside of the Japan *** occurrence of thin dolomitic layers embedded in diatomaceous sediments is on the basin scale rather than an isolated phenomenon. The genesis of dolomite in the natural environment has been one of the outstanding problems in geology over the last two centuries. However, we find that these thin dolomite layers mostly occur at depths where abrupt sedimentation rate change occurs. Two dolomite layers also coincide with the Miocene/Pliocene and Pliocene/Pleistocene age boundaries. It seems to suggest that the correlation between the dolomite layer occurrence and abrupt sedimentation rate change be intrinsically related to and a signature of dramatic changes in depositional environments. Considering the fact that the sedimentation rate at the ODP Leg 186 sites may be as fast as 250 m/m.y., high-resolution seismic stratigraphic model could help obtain a regional biostratigraphic or age model. The methodology can well be applied to other similar environments.

关键词： seismic resolution modeling synthetic seismogram thin-bed dolomite formation sedimentation rate age model

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EWING ＆ WORZEL PROFESSOR JOHN T. KUO: THE ONE STANDING HIGH AND ALONE

EWING ＆ WORZEL PROFESSOR JOHN T. KUO: THE ONE STANDING HIGH...

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理论与应用地球物理研讨会

作者： yue-feng sun Lamont-Doherty Earth Observatory Columbia University, Palisades, NY 10964, USA

＜正＞ Before coming to the United States for graduate learning in 1987, I had to two choices:either to go to University of California at Berkeley to study gravitation and unified theory *** E. Marsden’s guidance;or to go to Columbia Univesity to continue my education ingeophysics under ***’s guidance. These were all made possible by the help of Mr. Zhang Yi,the former President of the Karamay Oil Company, Mr. Li Licheng, the former Chief Geophysicistof the Karamay Oil Company, and Mr. Zheng Hu and Mr. Jin Hua of the former Ministry ofPetroleum of China. After many months of consideration, I finally made my decision and becameone of the last two students who were admitted to Columbia University for graduate studies ***’s guidance.

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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： feng Zhang Chenyang Zhang Linlin Wu Wei sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

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Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu yue Li Jun sun Shuyuan Du Xinpeng Di Yuguang Yang Bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

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Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

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Neural Regeneration Research 2025年第8期20卷 2199-2217页

作者： Zi Ye Runqing Liu Hangxing Wang Aizhen Zuo Cen Jin Nan Wang Huiqi sun Luqian feng Hua Yang The Clinical Medical College Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Infectious Diseases Department of Internal MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina School of Medical Imaging Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Gastroenterology First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion *** studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion ***,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional *** this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and *** therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box *** review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins *** review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk *** Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug ***,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

关键词： apoptosis autophagy blood-brain barrier dietary supplements drug hormones inflammation neuroprotection oxidative stress prognosis pyroptosis reperfusion injury risk factors RNA therapeutics

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Negative efficacy of antidepressants in pharmacotherapy of child and adolescent depression

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World Journal of Psychiatry 2025年第1期15卷 32-36页

作者： Min Xu Hai-Ying Jin feng-Li sun Wei-Dong Jin Department of Psychiatry Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Psychiatry Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Department of Psychiatry Zhejiang Provincial Mental Health CenterHangzhou 311122Zhejiang ProvinceChina

Antidepressants are the main drugs used to treat depression,but they have not been shown to be effective in the treatment of child and adolescent ***,many adolescent depression treatment guidelines still recommend the use of antidepressants,especially specific serotonin re-uptake *** studies have suggested that antidepressants have little therapeutic effect but many side effects,such as switching to mania,suicide,and non-suicidal self injury(NSSI),in the treatment of child and adolescent *** the process of developing guidelines,drug recommendations should not only focus on impro-ving symptoms,but they should also consider potential side *** review discusses the serious side effects of antidepressants,including switching to mania,suicide,and NSSI.

关键词： Child depression Adolescent depression Antidepressant Switch Suicide Non-suicidal self injury

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