The development of immunotherapies for lymphoma has undergone a revolutionary evolution over the past decades. Since the advent of rituximab as the first successful immunotherapy for B-cell non-Hodgkin lymphoma over t...The development of immunotherapies for lymphoma has undergone a revolutionary evolution over the past decades. Since the advent of rituximab as the first successful immunotherapy for B-cell non-Hodgkin lymphoma over two decades ago, a plethora of new immunotherapeutic approaches to treat lymphoma has ensued. Four of the most exciting classes of immunotherapies include:chimeric antigen receptor T-cells, bispecific antibodies, immune checkpoint inhibitors, and vaccines. However, with addition of these novel therapies the appropriate timing of treatment, optimal patient population, duration of therapy, toxicity, and cost must be considered. In this review, we describe the most-promising immunotherapeutic approaches for the treatment of lymphoma in clinical development, specifically focusing on clinical trials performed to date and strategies for improvement.展开更多
Copper possesses very strong chacophile properties,but under the conditions found in meteorites,its behavior is like that of siderophile elements.The Suizhou meteorite is a highly shocked L6 chondrite.Troilite and tae...Copper possesses very strong chacophile properties,but under the conditions found in meteorites,its behavior is like that of siderophile elements.The Suizhou meteorite is a highly shocked L6 chondrite.Troilite and taenite are considered the main primary carrier of copper in this meteorite,and the post-shock thermal episode is considered the main reason that elemental Cu migrates from its original host phase and forms metallic grains.The Suizhou meteorite contains a few very thin shock melt veins.The occurrence and behavior of metallic copper in this meteorite were studied by optical microscopic examination,electron microprobe analyses,and high-resolution X-ray elemental intensity mapping.Our results show that metallic copper is abundant in the Suizhou chondritic rock.Metallic copper grains adjacent to small troilite grains inside FeNi metal are the most common occurrence,and those at the FeNi metal–troilite interface are the second most common case.The metallic copper grains occurring at the interface of FeNi metal/troililte and silicate are rather rare.Metallic copper grains are not observed within the Suizhou shock veins,Instead,Cu in elemental form is transferred through shock metamorphism into FeNi metal+troilite intergrowths.Four diff erent occurrence types of Cu in the FeNi metal+troilite intergrowths have been identifi ed:the concentrations of Cu in the FeNi+FeS intergrowths for four occurrence types are rather close,we estimate it might be lower than 1 wt%.展开更多
A leukocyte segmentation method based on S component and B component images is proposed.Threshold segmentation operation is applied to get two binary images in S component and B component images.The samples used in th...A leukocyte segmentation method based on S component and B component images is proposed.Threshold segmentation operation is applied to get two binary images in S component and B component images.The samples used in this study are peripheral blood smears.It is easy tofind from the two binary images that gray values are the same at every corresponding pixels in theleukocyte cytoplasm region,but opposite in the other regions.The feature shows that "IMAGEAND"operation can be employed on the two binary images to segment the cytoplasm region ofleukocyte.By doing"IMAGE XOR"operation between cytoplasn region and nucleus region,theleukocyte segment ation can be retrieved effectively.The segmentation accuracy is evaluated by comparing the segmentation result of the proposed method with the manual segmentation by ahematologist.Experiment results show that the proposed method is of a higher segmentationaccuracy and it also performs well when leukocytes overlap_with erythrocytes.The averagesegmentation accuracy of the proposed method reaches 97.7%for segmenting five types ofleukocyte.Good segmentation results provide an important foundation for leukocytes aut omaticrecognition.展开更多
Magnetite from hydrothermal deposits may show compositional zoning with various mineral inclusions in response to the evolution of hydrothermal fluids.Magnetite from the Fenghuangshan Cu-Fe-Au skarn deposit(eastern Ch...Magnetite from hydrothermal deposits may show compositional zoning with various mineral inclusions in response to the evolution of hydrothermal fluids.Magnetite from the Fenghuangshan Cu-Fe-Au skarn deposit(eastern China)is a common mineral formed in the earlier stage of skarnization.Magnetite grains have dark gray and light gray zones and contain diverse mineral inclusions.Dark gray zones have higher Si,Ca,Al,and Mg contents than light gray zones.The magnetite matrix from dark gray zones shows superstructure along the[0-11]zone axis in fast Fourier transform patterns,different from magnetite in light gray zones with normal structure.Three types of mineral inclusions are identified within magnetite:nano-,micron-and submicron-nanometer inclusions.Nanoinclusions hosted in dark gray zones are actinolite,diopside,and trace element-rich magnetite,and these are likely formed by growth entrapment during magnetite crystallization at the skarn stage.The chainwidth order-disorder intergrowths of diopside nanoinclusion likely indicate fluctuating fluid compositions in a lattice scale.Submicron to nanometer inclusions at the boundary between dark gray and light gray zones are quartz,titanite,and Ti-rich magnetite,which were formed via a dissolution and reprecipitation process at the quartz-sulfide stage.Micron-inclusions randomly distributed in both dark and light gray zones include calcite,ankerite,quartz,and chlorite,and these were formed via penetration of fluids at the carbonate stage.Zoned magnetite was formed by fluid replacement,overgrowth,and fluid infilling.Our study highlights the importance of mineral inclusion assemblages,and textural and chemical zonation of magnetite in constraining fluid evolution.展开更多
Based on empirical likelihood method and QR decomposition technique, an orthogonality empirical likelihood based estimation method for the fixed effects in linear mixed effects models is proposed. Under some regularit...Based on empirical likelihood method and QR decomposition technique, an orthogonality empirical likelihood based estimation method for the fixed effects in linear mixed effects models is proposed. Under some regularity conditions, the proposed empirical log-likelihood ratio is proved to be asymptotically chi-squared, and then the confidence intervals for the fixed effects are constructed. The proposed estimation procedure is not affected by the random effects,and then the resulting estimator is more effective. Some simulations and a real data application are conducted for further illustrating the performances of the proposed method.展开更多
Line-commutated-converter-based high-voltage direct current(LCC-HVDC)represents an important approach for transmitting large-scale integrated renewable power over long distances.However,coordination of various discret...Line-commutated-converter-based high-voltage direct current(LCC-HVDC)represents an important approach for transmitting large-scale integrated renewable power over long distances.However,coordination of various discrete and continuous adjustment devices,as well as the complex automatic voltage control problem bring great challenges for voltage control and var dispatch in converter stations(CSs).Besides,traditional approaches may suffer from frequent filter switching issues or conservativeness.To address these issues,this paper proposes a hierarchical robust voltage dispatching schedule consisting of a day-ahead schedulable period plan and an intraday model predictive control(MPC)-based rolling scheduling,which fully considers coordination of multifarious adjustment equipment with different response-time constants and control characteristics in CSs in multiple time dimensions.This method can implement adaptive adjustment of CS discrete/continuous regulating devices with sufficient dynamic var reserves under CS mutable operational conditions caused by renewable energy fluctuation.The day-ahead schedulable period plan ensures global allocation of discrete equipment action resources.MPC-based intraday rolling dispatch is used to overcome conservativeness of the traditional method and achieve automatic reactive power compensation,as well as voltage control of converter station.In a case study,a modified IEEE 9-bus system with wind farms is used to verify the proposed method.展开更多
Cadmium(Cd)has received widespread attention owing to its persistent toxicity and non-degradability.Cd in the human body is mainly absorbed from the external environment and is usually assessed using urinary Cd.Hunan ...Cadmium(Cd)has received widespread attention owing to its persistent toxicity and non-degradability.Cd in the human body is mainly absorbed from the external environment and is usually assessed using urinary Cd.Hunan Province is the heartland of the Chinese non-ferrous mining area,where several serious Cd pollution events have occurred,including high levels of Cd in the urine of residents.However,the environmental factors influencing high urinary Cd levels(UCLs)in nearby residents remain unclear.Therefore,211 nearby residents’UCLs and the corresponding sociological characteristics from nine groundwater samples in this area were analyzed using statistical analysis models.Groundwater Cd concentration ranged from 0.02 to 1.15μg/L,aligning with class III of the national standard;the range of UCL of nearby residents was 0.37–36.60μg/L,exceeding the national guideline of 0–2.5μg/L.Groundwater Cd levels were positively correlated with the UCL(P<0.001,correlation coefficient 95%CI=9.68,R^(2)=0.06).In addition,sociological characteristics,such as smoking status and education level,also affect UCL.All results indicate that local governments should strengthen the prevention and abatement of groundwater Cd pollution.This study is the first to systematically evaluate the relationship between groundwater Cd and UCL using internal and external environmental exposure data.These findings provide essential bases for relevant departments to reduce Cd exposure in regions where the heavy metal industry is globally prevalent.展开更多
Numerous sedimentary phosphorites in Southwest China were formed around the Precambrian–Cambrian transition(PC–C),including the upper Ediacaran Doushantuo Formation and lower Cambrian Gezhongwu Formation.The Gezhong...Numerous sedimentary phosphorites in Southwest China were formed around the Precambrian–Cambrian transition(PC–C),including the upper Ediacaran Doushantuo Formation and lower Cambrian Gezhongwu Formation.The Gezhongwu phosphorites in Zhijin exhibit marked rare earth element(REE)enrichment(>1000 ppm),and may represent new REE resources.Although the main characteristics of the Gezhongwu phosphorites have been well constrained,the REE enrichment mechanisms remain unclear.We undertook a comparative study of three typical sedimentary phosphorites with variable REE contents formed at the PC–C transition in central Guizhou Province,Southwest China.These include sections A and B of the Doushantuo phosphorites(560±8 Ma)from the Weng’an area(i.e.,WA-A and WA-B),and the Gezhongwu phosphorites(527±24 Ma)from the Zhijin area(ZJ).The phosphorites were investigated with state-of-the-art macroscale to nanoscale analytical techniques.In contrast to the extraordinary REE enrichment in the ZJ phosphorites(average RREE=1157 ppm),the phosphorites in WA-A(average RREE=234 ppm)and WA-B(average RREE=114 ppm)are REE-poor.Elemental mapping by laser ablation–inductively coupled plasma–mass spectrometry,along with transmission electron microscopy analyses,showed the REEs in the studied phosphorites are hosted in nanoscale francolites.The 87Sr/86Sr and Y/Ho ratios of the francolite grains indicate that greater terrigenous input may have led to more REE enrichment in the WA-A than WA-B phosphorites,but this cannot explain the extraordinary REE enrichment in the ZJ phosphorites.The F/P_(2)O_(5)values of the francolite grains in the ZJ phosphorites(~0.097)are higher than those in the WA-A(~0.084)and WA-B(~0.084)phosphorites,and the grain size of the francolite in the ZJ phosphorites(~89.9 nm)is larger than those in the WA-A(~56.6 nm)and WA-B(~57.4 nm)phosphorites,indicative of more intense reworking of the ZJ than WA phosphorites during early diagenesis.A plot of Nd concentration versus Ce/Ce^(*)reveals that lower sedimentation rates characterized the ZJ phosphorites.Therefore,intense sedimentary reworking during early diagenesis resulted in more REEs being sequestered by the marine phosphates from seawater and pore waters at a lower sedimentation rate,which resulted in the extraordinary REE enrichment in the ZJ phosphorites.Our findings highlight the multiple factors that controlled formation of sedimentary phosphorites around the PC–C transition(especially the intense reworking and redox conditions of the overlying seawater),and provide further insights into REE enrichment in sedimentary phosphorites worldwide.展开更多
The Southern Yellow Sea Cold Water Mass(YSCWM) is closely related to the modern circulation system of the east China shelf seas, which has significantly influenced regional marine environmental changes. The study of t...The Southern Yellow Sea Cold Water Mass(YSCWM) is closely related to the modern circulation system of the east China shelf seas, which has significantly influenced regional marine environmental changes. The study of the Holocene evolution of the YSCWM will greatly improve our understanding of the mechanisms of regional environmental change. Benthic foraminifera are sensitive to bottom water environmental changes and can serve as useful indicators in bottom water environmental reconstruction. In this study, benthic foraminifera were analyzed in core N02 from the northwestern margin of the southern Yellow Sea Mud to decipher the phase evolution of the YSCWM during the last 7 kyr. Benthic foraminifera census counts and Q-mode factor analysis indicate that the Holocene sedimentary environment can be divided into three stages: From6.9–5.0 ka, the fauna was dominated by Ammonia ketienziensis, indicating that the YSCWM was at its strongest during the last 7 kyr, while the Yellow Sea Coastal Current(YSCC) had a weak influence on the bottom water of the study area. From 5.0–2.9 ka,the relative abundance of Hanzawaia nipponica remarkably increased while the abundance of A. ketienziensis decreased significantly, reflecting that the strength of the YSCWM was relatively weak and the range of the YSCWM might have contracted. The influence of the YSCC on the bottom water might have slightly increased, although its influence was still weak during this time. A notable increase in low-temperature and low-salinity species, such as Protelphidium tuberculatum and Buccella spp. has occurred since 2.9 ka, indicating that the YSCC has had a strong influence on bottom water during this period,while the strength of the YSCWM has been at its weakest during the last 7 kyr. Generally, the influence of the YSCWM and the YSCC on the bottom water properties of the study area show an obvious seesaw pattern, with one's influence increasing while the other's influence decreases and vice versa. The fluctuations in the strength of YSCWM during the Holocene may be caused by the different effect allocations of regional climatic factors(i.e. El Ni?o Southern Oscillation, East Asian Winter Monsoon,summer insolation in the northern hemisphere, etc.) acting on the circulation system during different periods.展开更多
Impact events have played a crucial role in the formation and evolution of the Moon,as evidenced by the numerous of impact craters on its surface,indicating a long history spanning over 4 billion years characterized b...Impact events have played a crucial role in the formation and evolution of the Moon,as evidenced by the numerous of impact craters on its surface,indicating a long history spanning over 4 billion years characterized by numerous such occurrences.As the moon evolved,it is likely that the early impact craters formed by the bombardment event have subsequently been overlaid by later impacts.However,limited samples and research methods have hindered the discovery of evidence of impacts on the lunar surface.Therefore,this article gives an overview of the study of shock metamorphism in lunar minerals,some new progress in the past 2 decades is reviewed,and the implications of these new discoveries for the composition of the Moon’s crust,history of impact,and the Moon’s evolution are discussed.In addition,some of the issues and limitations that have arisen in the study of lunar shock metamorphism are also summarized.Given the difficulties in the studying of lunar high-pressure minerals and shock metamorphic microstructure using traditional optical microscope,we suggest that the latest nanomineralogical research methods,such as focused ion beam,electron backscatter diffraction,atom probe tomography,Raman spectroscopy,and 3-dimensional electron diffraction,are rational and essential to address the challenges associated with the research on lunar shock metamorphism.展开更多
基金supported by NIH grants(Grant No.R01CA136934,and R01 CA193167)
文摘The development of immunotherapies for lymphoma has undergone a revolutionary evolution over the past decades. Since the advent of rituximab as the first successful immunotherapy for B-cell non-Hodgkin lymphoma over two decades ago, a plethora of new immunotherapeutic approaches to treat lymphoma has ensued. Four of the most exciting classes of immunotherapies include:chimeric antigen receptor T-cells, bispecific antibodies, immune checkpoint inhibitors, and vaccines. However, with addition of these novel therapies the appropriate timing of treatment, optimal patient population, duration of therapy, toxicity, and cost must be considered. In this review, we describe the most-promising immunotherapeutic approaches for the treatment of lymphoma in clinical development, specifically focusing on clinical trials performed to date and strategies for improvement.
基金supported by Science and Technology Planning Project of Guangdong Province,2023B1212060048.
文摘Copper possesses very strong chacophile properties,but under the conditions found in meteorites,its behavior is like that of siderophile elements.The Suizhou meteorite is a highly shocked L6 chondrite.Troilite and taenite are considered the main primary carrier of copper in this meteorite,and the post-shock thermal episode is considered the main reason that elemental Cu migrates from its original host phase and forms metallic grains.The Suizhou meteorite contains a few very thin shock melt veins.The occurrence and behavior of metallic copper in this meteorite were studied by optical microscopic examination,electron microprobe analyses,and high-resolution X-ray elemental intensity mapping.Our results show that metallic copper is abundant in the Suizhou chondritic rock.Metallic copper grains adjacent to small troilite grains inside FeNi metal are the most common occurrence,and those at the FeNi metal–troilite interface are the second most common case.The metallic copper grains occurring at the interface of FeNi metal/troililte and silicate are rather rare.Metallic copper grains are not observed within the Suizhou shock veins,Instead,Cu in elemental form is transferred through shock metamorphism into FeNi metal+troilite intergrowths.Four diff erent occurrence types of Cu in the FeNi metal+troilite intergrowths have been identifi ed:the concentrations of Cu in the FeNi+FeS intergrowths for four occurrence types are rather close,we estimate it might be lower than 1 wt%.
文摘A leukocyte segmentation method based on S component and B component images is proposed.Threshold segmentation operation is applied to get two binary images in S component and B component images.The samples used in this study are peripheral blood smears.It is easy tofind from the two binary images that gray values are the same at every corresponding pixels in theleukocyte cytoplasm region,but opposite in the other regions.The feature shows that "IMAGEAND"operation can be employed on the two binary images to segment the cytoplasm region ofleukocyte.By doing"IMAGE XOR"operation between cytoplasn region and nucleus region,theleukocyte segment ation can be retrieved effectively.The segmentation accuracy is evaluated by comparing the segmentation result of the proposed method with the manual segmentation by ahematologist.Experiment results show that the proposed method is of a higher segmentationaccuracy and it also performs well when leukocytes overlap_with erythrocytes.The averagesegmentation accuracy of the proposed method reaches 97.7%for segmenting five types ofleukocyte.Good segmentation results provide an important foundation for leukocytes aut omaticrecognition.
基金financially supported by the CAS Hundred Talents Program to Xiao-Wen Huangthe National Natural Science Foundation of China(No.42173070)the Special Fund of the State Key Laboratory of Ore Deposit Geochemistry(No.202101)。
文摘Magnetite from hydrothermal deposits may show compositional zoning with various mineral inclusions in response to the evolution of hydrothermal fluids.Magnetite from the Fenghuangshan Cu-Fe-Au skarn deposit(eastern China)is a common mineral formed in the earlier stage of skarnization.Magnetite grains have dark gray and light gray zones and contain diverse mineral inclusions.Dark gray zones have higher Si,Ca,Al,and Mg contents than light gray zones.The magnetite matrix from dark gray zones shows superstructure along the[0-11]zone axis in fast Fourier transform patterns,different from magnetite in light gray zones with normal structure.Three types of mineral inclusions are identified within magnetite:nano-,micron-and submicron-nanometer inclusions.Nanoinclusions hosted in dark gray zones are actinolite,diopside,and trace element-rich magnetite,and these are likely formed by growth entrapment during magnetite crystallization at the skarn stage.The chainwidth order-disorder intergrowths of diopside nanoinclusion likely indicate fluctuating fluid compositions in a lattice scale.Submicron to nanometer inclusions at the boundary between dark gray and light gray zones are quartz,titanite,and Ti-rich magnetite,which were formed via a dissolution and reprecipitation process at the quartz-sulfide stage.Micron-inclusions randomly distributed in both dark and light gray zones include calcite,ankerite,quartz,and chlorite,and these were formed via penetration of fluids at the carbonate stage.Zoned magnetite was formed by fluid replacement,overgrowth,and fluid infilling.Our study highlights the importance of mineral inclusion assemblages,and textural and chemical zonation of magnetite in constraining fluid evolution.
基金Supported by the National Social Science Foundation of China(Grant No.18BTJ035).
文摘Based on empirical likelihood method and QR decomposition technique, an orthogonality empirical likelihood based estimation method for the fixed effects in linear mixed effects models is proposed. Under some regularity conditions, the proposed empirical log-likelihood ratio is proved to be asymptotically chi-squared, and then the confidence intervals for the fixed effects are constructed. The proposed estimation procedure is not affected by the random effects,and then the resulting estimator is more effective. Some simulations and a real data application are conducted for further illustrating the performances of the proposed method.
基金supported by the Youth Program of National Natural Science Foundation of China(No.52007017)the National Science Fund for Outstanding Young Scholar of China(No.51725701).
文摘Line-commutated-converter-based high-voltage direct current(LCC-HVDC)represents an important approach for transmitting large-scale integrated renewable power over long distances.However,coordination of various discrete and continuous adjustment devices,as well as the complex automatic voltage control problem bring great challenges for voltage control and var dispatch in converter stations(CSs).Besides,traditional approaches may suffer from frequent filter switching issues or conservativeness.To address these issues,this paper proposes a hierarchical robust voltage dispatching schedule consisting of a day-ahead schedulable period plan and an intraday model predictive control(MPC)-based rolling scheduling,which fully considers coordination of multifarious adjustment equipment with different response-time constants and control characteristics in CSs in multiple time dimensions.This method can implement adaptive adjustment of CS discrete/continuous regulating devices with sufficient dynamic var reserves under CS mutable operational conditions caused by renewable energy fluctuation.The day-ahead schedulable period plan ensures global allocation of discrete equipment action resources.MPC-based intraday rolling dispatch is used to overcome conservativeness of the traditional method and achieve automatic reactive power compensation,as well as voltage control of converter station.In a case study,a modified IEEE 9-bus system with wind farms is used to verify the proposed method.
基金supported by the National Natural Science Foundation of China(Nos.81800393,82170437,and 41877297)the Outstanding Young Investigator of Hunan province(No.2020JJ2056)+3 种基金the Hunan Youth Talent Project(No.2019RS2014)the Key Research and Development Project of Hunan(No.2020WK2010)the National Key Research and Development Program(No.2018YFC1311300)the Investigation and Evaluation of Groundwater Pollution in Key Areas of Central and South China by China Geological Survey(No.12120114029601).
文摘Cadmium(Cd)has received widespread attention owing to its persistent toxicity and non-degradability.Cd in the human body is mainly absorbed from the external environment and is usually assessed using urinary Cd.Hunan Province is the heartland of the Chinese non-ferrous mining area,where several serious Cd pollution events have occurred,including high levels of Cd in the urine of residents.However,the environmental factors influencing high urinary Cd levels(UCLs)in nearby residents remain unclear.Therefore,211 nearby residents’UCLs and the corresponding sociological characteristics from nine groundwater samples in this area were analyzed using statistical analysis models.Groundwater Cd concentration ranged from 0.02 to 1.15μg/L,aligning with class III of the national standard;the range of UCL of nearby residents was 0.37–36.60μg/L,exceeding the national guideline of 0–2.5μg/L.Groundwater Cd levels were positively correlated with the UCL(P<0.001,correlation coefficient 95%CI=9.68,R^(2)=0.06).In addition,sociological characteristics,such as smoking status and education level,also affect UCL.All results indicate that local governments should strengthen the prevention and abatement of groundwater Cd pollution.This study is the first to systematically evaluate the relationship between groundwater Cd and UCL using internal and external environmental exposure data.These findings provide essential bases for relevant departments to reduce Cd exposure in regions where the heavy metal industry is globally prevalent.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.41825003,41921003)Key Research Program of the Institute of Geology&Geophysics,CAS(Grant No.IGGCAS-201901)+2 种基金Guangdong Special Support Program(Grant No.2019TX05L169)Science and Technology Planning Project of Guangdong Province,China(Grant No.2023B1212060048)Youth Innovation Promotion Association CAS(Grant No.2021353).
文摘Numerous sedimentary phosphorites in Southwest China were formed around the Precambrian–Cambrian transition(PC–C),including the upper Ediacaran Doushantuo Formation and lower Cambrian Gezhongwu Formation.The Gezhongwu phosphorites in Zhijin exhibit marked rare earth element(REE)enrichment(>1000 ppm),and may represent new REE resources.Although the main characteristics of the Gezhongwu phosphorites have been well constrained,the REE enrichment mechanisms remain unclear.We undertook a comparative study of three typical sedimentary phosphorites with variable REE contents formed at the PC–C transition in central Guizhou Province,Southwest China.These include sections A and B of the Doushantuo phosphorites(560±8 Ma)from the Weng’an area(i.e.,WA-A and WA-B),and the Gezhongwu phosphorites(527±24 Ma)from the Zhijin area(ZJ).The phosphorites were investigated with state-of-the-art macroscale to nanoscale analytical techniques.In contrast to the extraordinary REE enrichment in the ZJ phosphorites(average RREE=1157 ppm),the phosphorites in WA-A(average RREE=234 ppm)and WA-B(average RREE=114 ppm)are REE-poor.Elemental mapping by laser ablation–inductively coupled plasma–mass spectrometry,along with transmission electron microscopy analyses,showed the REEs in the studied phosphorites are hosted in nanoscale francolites.The 87Sr/86Sr and Y/Ho ratios of the francolite grains indicate that greater terrigenous input may have led to more REE enrichment in the WA-A than WA-B phosphorites,but this cannot explain the extraordinary REE enrichment in the ZJ phosphorites.The F/P_(2)O_(5)values of the francolite grains in the ZJ phosphorites(~0.097)are higher than those in the WA-A(~0.084)and WA-B(~0.084)phosphorites,and the grain size of the francolite in the ZJ phosphorites(~89.9 nm)is larger than those in the WA-A(~56.6 nm)and WA-B(~57.4 nm)phosphorites,indicative of more intense reworking of the ZJ than WA phosphorites during early diagenesis.A plot of Nd concentration versus Ce/Ce^(*)reveals that lower sedimentation rates characterized the ZJ phosphorites.Therefore,intense sedimentary reworking during early diagenesis resulted in more REEs being sequestered by the marine phosphates from seawater and pore waters at a lower sedimentation rate,which resulted in the extraordinary REE enrichment in the ZJ phosphorites.Our findings highlight the multiple factors that controlled formation of sedimentary phosphorites around the PC–C transition(especially the intense reworking and redox conditions of the overlying seawater),and provide further insights into REE enrichment in sedimentary phosphorites worldwide.
基金supported by the National Basic Research Program of China (Grant No. 2010CB428901)the National Natural Science Foundation of China (Grant Nos. 41476040 & 91228207)the Strategic Special Project of Chinese Academy of Sciences (Grant No. XDA11030104)
文摘The Southern Yellow Sea Cold Water Mass(YSCWM) is closely related to the modern circulation system of the east China shelf seas, which has significantly influenced regional marine environmental changes. The study of the Holocene evolution of the YSCWM will greatly improve our understanding of the mechanisms of regional environmental change. Benthic foraminifera are sensitive to bottom water environmental changes and can serve as useful indicators in bottom water environmental reconstruction. In this study, benthic foraminifera were analyzed in core N02 from the northwestern margin of the southern Yellow Sea Mud to decipher the phase evolution of the YSCWM during the last 7 kyr. Benthic foraminifera census counts and Q-mode factor analysis indicate that the Holocene sedimentary environment can be divided into three stages: From6.9–5.0 ka, the fauna was dominated by Ammonia ketienziensis, indicating that the YSCWM was at its strongest during the last 7 kyr, while the Yellow Sea Coastal Current(YSCC) had a weak influence on the bottom water of the study area. From 5.0–2.9 ka,the relative abundance of Hanzawaia nipponica remarkably increased while the abundance of A. ketienziensis decreased significantly, reflecting that the strength of the YSCWM was relatively weak and the range of the YSCWM might have contracted. The influence of the YSCC on the bottom water might have slightly increased, although its influence was still weak during this time. A notable increase in low-temperature and low-salinity species, such as Protelphidium tuberculatum and Buccella spp. has occurred since 2.9 ka, indicating that the YSCC has had a strong influence on bottom water during this period,while the strength of the YSCWM has been at its weakest during the last 7 kyr. Generally, the influence of the YSCWM and the YSCC on the bottom water properties of the study area show an obvious seesaw pattern, with one's influence increasing while the other's influence decreases and vice versa. The fluctuations in the strength of YSCWM during the Holocene may be caused by the different effect allocations of regional climatic factors(i.e. El Ni?o Southern Oscillation, East Asian Winter Monsoon,summer insolation in the northern hemisphere, etc.) acting on the circulation system during different periods.
基金supported by the Special Lunar Project of Chinese Academy of Sciences(ZDBS-SSW-JSC007-11)Director’s Fund of Guangzhou Institute of Geochemistry,CAS(2022SZJJZD-03)+2 种基金National Natural Science Foundation of China(42241127)National Natural Science Foundation of China-Academic Divisions of Chinese Academy of Sciences Frontier Interdisciplinary Research Strategic Research Joint Funding Project(L2224032 and XK2022DXC004)the Youth Innovation Promotion Association CAS(2021353).
文摘Impact events have played a crucial role in the formation and evolution of the Moon,as evidenced by the numerous of impact craters on its surface,indicating a long history spanning over 4 billion years characterized by numerous such occurrences.As the moon evolved,it is likely that the early impact craters formed by the bombardment event have subsequently been overlaid by later impacts.However,limited samples and research methods have hindered the discovery of evidence of impacts on the lunar surface.Therefore,this article gives an overview of the study of shock metamorphism in lunar minerals,some new progress in the past 2 decades is reviewed,and the implications of these new discoveries for the composition of the Moon’s crust,history of impact,and the Moon’s evolution are discussed.In addition,some of the issues and limitations that have arisen in the study of lunar shock metamorphism are also summarized.Given the difficulties in the studying of lunar high-pressure minerals and shock metamorphic microstructure using traditional optical microscope,we suggest that the latest nanomineralogical research methods,such as focused ion beam,electron backscatter diffraction,atom probe tomography,Raman spectroscopy,and 3-dimensional electron diffraction,are rational and essential to address the challenges associated with the research on lunar shock metamorphism.
