Rivers and groundwater are the main water sources for cities.The mutual transformation between river water and groundwater makes it difficult to accurately evaluate and rationally utilize water resources.Scientificall...Rivers and groundwater are the main water sources for cities.The mutual transformation between river water and groundwater makes it difficult to accurately evaluate and rationally utilize water resources.Scientifically quantifying the interaction of surface water and groundwater remains challenging.Taking Chan River Basin as an example,this study aimed to determine the interconversion processes of groundwater and surface water by hydrogeochemical genesis mechanism analysis,isotope tracing,and end-member mixing analysis(EMMA).28 surface water samples and 23 groundwater samples were collected and analyzed during December 2023 and January 2024.Results showed thewater bodies in the study area were dominated by the HCO_(3)-Ca,HCO_(3)-Ca·Mg·Na,and HCO_(3)·SO_(4)-Ca·Na types,with hydrogeochemical processes controlled by the weathering and dissolution of both carbonate and silicate rock minerals.The river water in the upper reaches of the study area is mainly recharged by groundwater,with the average recharge ratio of 54.10%.Similarly,river water is still recharged by groundwater in the middle reaches,the average recharge ratio changes to 28.61%.In the downstream area,where Xi’an City located,due to the heavy exploitation of groundwater,the river water recharges to groundwater with an average recharge ratio of 85.23%,although in the immediate middle reaches,groundwater still replenishes surface waterwith a recharge rate of 75.00%.The results laid the bases for the reasonable utilization of water resources in the Chan River Basin and also served as a reference in other regions of the world.展开更多
Three different types of gold and silver deposits in Zhejiang Province(Huangshan gold deposit, Zhilingtou gold-silver deposit and Haoshi silver deposit) showmarked differences in lead and strontium isotopic compositio...Three different types of gold and silver deposits in Zhejiang Province(Huangshan gold deposit, Zhilingtou gold-silver deposit and Haoshi silver deposit) showmarked differences in lead and strontium isotopic composition, suggesting three differentsources and geneses of these deposits. The Huangshan gold deposit features low initial Srisotope ratios and low μ values or low content of radiogenic Pb and its ore-forming materialscame primarily from the upper mantle; the Zhilingtou gold-silver deposit shows high initial Srisotope ratios and high μ values or high content of radiogenic Pb and the ore-forming materialswere derived mainly from the upper crust; and the Haoshi silver deposit has its Pb and Srisotope ratios between the above two cases with the ore-forming materials stemming from boththe mantle and the crust. The characteristic Pb isotopic composition may serve as an indicatorfor prospecting for different types of ore deposits.展开更多
Using Na15NO3 and 15NH4Cl as tracer, we studied the transfer of 15N along the food chain composed oforganisms such as Platymonas subcordiformis, Artemia salina, Penaeus penicillatus and Liza carinatus . The abundancea...Using Na15NO3 and 15NH4Cl as tracer, we studied the transfer of 15N along the food chain composed oforganisms such as Platymonas subcordiformis, Artemia salina, Penaeus penicillatus and Liza carinatus . The abundanceand atomic percentage of 15N in each organism, as well as the transfer of 15N among different biological phases weremeasured. Results show that, in the nutrient transfer from low level to high level along the md chain in the mediaof 15NH4Cl, the transfer rate of Artemia salina→Liza carinatus exceeded 3% and was higher than that in Na15NO3; the accumulation of 15N in the bodies of Liza carinatus with 15NH4Cl as media was also higher than that withNa 15NO3 as media.展开更多
Anaerobic ammonium oxidation coupled to iron(III)reduction(Feammox)process has recently been recognized as an important pathway for removing ammonium in various natural habitats.However,our understanding for Feammox i...Anaerobic ammonium oxidation coupled to iron(III)reduction(Feammox)process has recently been recognized as an important pathway for removing ammonium in various natural habitats.However,our understanding for Feammox in river–estuary continuum is limited.In this study,stable isotope tracers and high-throughput amplicon sequencing were employed to determine Feammox rates and identify associated microbial communities in sediments along the Yangtze river–estuary continuum.Feammox rates averaged 0.0058±0.0069 mg N/(kg·d)and accounted for approximately 22.3%of the ammonium removed from the sediments.Sediment Fe(III),ammonium(NH_(4)^(+)),total organic carbon(TOC),and pH were identified as important factors influencing Feammox rates.Additionally,Spirochaeta,Caldilineaceae_uncultured,and Ignavibacterium were found potentially associated with Feammox,which had not been documented as Feammox-associated microbial taxa previously.This study demonstrates that Feammox plays a vital role in ammonium removal within the Yangtze river–estuary continuum,providing greater insight into nitrogen removal and cycling in aquatic ecosystems.展开更多
The Saxi tungsten deposit,located in the Laojunshan ore district of southeastern Yunnan Province,is a significant W-polymetallic deposit.The origins of tungstenbearing pegmatite dikes and quartz vein mineralization in...The Saxi tungsten deposit,located in the Laojunshan ore district of southeastern Yunnan Province,is a significant W-polymetallic deposit.The origins of tungstenbearing pegmatite dikes and quartz vein mineralization in the Saxi deposit remain poorly understood.This study employs in situ U-Pb dating of apatite from the altered granite,along with trace element and S-Pb isotopic analysis of arsenopyrite,to investigate the timing,source of ore-forming fluids and the mechanisms of tungsten enrichment.The apatite in the altered granite yields a U-Pb age of 147.0±4.0 Ma,indicating magmatic activity during the Early Cretaceous.Three generations of arsenopyrite(Apy)are identified:Apy-1 in the altered granite,Apy-2 in the pegmatite dikes and Apy-3 in the quartz veins.The S/Fe ratios for Apy-1,Apy-2 and Apy-3 range from 0.98 to 1.09,0.89 to 0.92 and 0.86 to 1.02,respectively(average 0.97),suggesting a magmatic-hydrothermal origin.Sulfur isotope values(δ^(34)S=4.29‰-8.11‰)indicate that it was likely sourced from deep magmatic-hydrothermal fluids.Lead isotopic compositions of arsenopyrite suggest that the granitic parental magma is derived from the upper crust.These findings point to a magmatic-hydrothermal origin for the vein-type tungsten mineralization,linked to a concealed magmatichydrothermal system in the Early Cretaceous.展开更多
Plant roots dynamics responses to elevated atmospheric CO2 concentration, increased temperature and changed precipitation can be a key link between plant growth and long-term changes in soil organic matter and ecosyst...Plant roots dynamics responses to elevated atmospheric CO2 concentration, increased temperature and changed precipitation can be a key link between plant growth and long-term changes in soil organic matter and ecosystem carbon balance. This paper reviews some experiments and hypotheses developed in this area, which mainly include plant fine roots growth, root turnover, root respiration and other root dynamics responses to elevated CO2 and global climate change. Some recent new methods of studying root systems were also discussed and summarized. It holds herein that the assemblage of information about root turnover patterns, root respiration and other dynamic responses to elevated atmospheric CO2 and global climatic change can help to better understand and explore some new research areas. In this paper, some research challenges in the plant root responses to the elevated CO2 and other environmental factors during global climate change were also demonstrated.展开更多
There is an urgent need to elucidate the pathogenesis of myocardial ischemia(MI)and potential drug treatments.Here,the anti-MI mechanism and material basis of Ginkgo biloba L.extract(GBE)were studied from the perspect...There is an urgent need to elucidate the pathogenesis of myocardial ischemia(MI)and potential drug treatments.Here,the anti-MI mechanism and material basis of Ginkgo biloba L.extract(GBE)were studied from the perspective of energy metabolism flux regulation.Metabolic flux analysis(MFA)was performed to investigate energy metabolism flux disorder and the regulatory nodes of GBE components in isoproterenol(ISO)-induced ischemia-like cardiomyocytes.It showed that[U-13 C]glucose derived m+2 isotopologues from the upstream tricarboxylic acid(TCA)cycle metabolites were markedly accumulated in ISO-injured cardiomyocytes,but the opposite was seen for the downstream metabolites,while their total cellular concentrations were increased.This indicates a blockage of carbon flow from glycolysis and enhanced anaplerosis from other carbon sources.A Seahorse test was used to screen for GBE components with regulatory effects on mitochondrial aerobic respiratory dysfunction.It showed that bilobalide protected against impaired mitochondrial aerobic respiration.MFA also showed that bilobalide significantly modulated the TCA cycle flux,reduced abnormal metabolite accumulation,and balanced the demand of different carbon sources.Western blotting and PCR analysis showed that bilobalide decreased the enhanced expression of key metabolic enzymes in injured cells.Bilobalide’s efficacy was verified by in vivo experiments in rats.This is the first report to show that bilobalide,the active ingredient of GBE,protects against MI by rescuing impaired TCA cycle flux.This provides a new mechanism and potential drug treatment for MI.It also shows the potential of MFA/Seahorse combination as a powerful strategy for pharmacological research on herbal medicine.展开更多
Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identi...Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.展开更多
In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground a...In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground and diverse, or even irregular, operations in sampling and testing procedures, CRI determination is usually faced with many difficulties and uncertainties. In addition, more difficulties occur in an investigation of a large-scale region because of time constraints and measurement cost limitations. In this study, traditional CRI acquiring methods were summarized first, and then a new complex scheme was established, involving seven core steps and coupling the model estimate and sample measurement. The above CRI determination methodology was implemented in the central-eastern Inner Mongolia Plateau. The case study results showed that the CRI in the dark chestnut soil sub-region, located in the east and south of Xing＇an City, exhibited 2447 Bq·m–2; the CRI in the aeolian sandy soil sub-region, positioned in the south central Tongliao City and central Chifeng City, showed 2430 Bq·m–2; the CRI in the sandy chernozem soil sub-region, situated in the northwestern Chifeng City, presented 2384 Bq·m–2; and the CRI in the chestnut soil sub-region, in the southern Xilin Gol City, was 2368 Bq·m–2. The newly proposed CRI determination scheme was proved effective, and the determined CRI plots and CRI values were convincing. The methodology offered a framework for 137 Cs tracing studies in large-scale regions or long-distance transects.展开更多
With low concentration of stable lead isotope as the tracer, using inductively coupled plasma mass spectrometry （ICP-MS）, the lead absorption of tea plants as well as the distribution and migration pattern of lead i...With low concentration of stable lead isotope as the tracer, using inductively coupled plasma mass spectrometry （ICP-MS）, the lead absorption of tea plants as well as the distribution and migration pattern of lead in plants under different pH environments and spraying introduction of lead sources were studied through pot trial. The results showed that tea plants were very sensitive to atmospheric lead source pollution; atmospheric lead source pollution had a tendency of moving up to the top （bud） ; low pH conditions enhanced lead absorption of plants and promoted upward migration of lead in plants. The experimental method is closer to the actual situation that plants are exposed to low concentration pollution, and could distinguish experimentally introduced lead source from environmentally introduced lead source.展开更多
Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite wer...Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite were close to the δ13CPDB value of original magma; δ30Si values of the samples at the ore-forming stage were close to the δ30Si value range of magma, δ30Si values of partial samples were far away from it; Cu isotopic compositions of massive chalcopyrite formed at the early ore-forming stage are higher than that of veinal chalcopyrite formed at the later ore-forming stage. The results show that ore-forming materials were mainly derived from the porphyry body, and part of them were from wall rock materials.展开更多
Deconvolution of potential drug targets of the central nervous system(CNS)is particularly challenging because of the complicated structure and function of the brain.Here,a spatiotemporally resolved metabolomics and is...Deconvolution of potential drug targets of the central nervous system(CNS)is particularly challenging because of the complicated structure and function of the brain.Here,a spatiotemporally resolved metabolomics and isotope tracing strategy was proposed and demonstrated to be powerful for deconvoluting and localizing potential targets of CNS drugs by using ambient mass spectrometry imaging.This strategy can map various substances including exogenous drugs,isotopically labeled metabolites,and various types of endogenous metabolites in the brain tissue sections to illustrate their microregional distribution pattern in the brain and locate drug action-related metabolic nodes and pathways.The strategy revealed that the sedative-hypnotic drug candidate YZG-331 was prominently distributed in the pineal gland and entered the thalamus and hypothalamus in relatively small amounts,and can increase glutamate decarboxylase activity to elevateγ-aminobutyric acid(GABA)levels in the hypothalamus,agonize organic cation transporter 3 to release extracellular histamine into peripheral circulation.These findings emphasize the promising capability of spatiotemporally resolved metabolomics and isotope tracing to help elucidate the multiple targets and the mechanisms of action of CNS drugs.展开更多
Diet interventions such as calorie restriction or time-restricted feeding offer potential for weight management,but long-term success is often hindered by poor adherence due to the rewarding effects of sugars.In this ...Diet interventions such as calorie restriction or time-restricted feeding offer potential for weight management,but long-term success is often hindered by poor adherence due to the rewarding effects of sugars.In this study,we demonstrate that sulfur amino acid restriction(SAAR)diets promote rapid fat loss without impairing appetite and physiological locomotion,outperforming diets with restricted branched-chain amino acids.Weekly cycling of SAAR diets preserves metabolic benefits,such as reduced fat mass and improved glucose sensitivity.Metabolic analysis and in vivo isotope tracing revealed a shift toward carbohydrate oxidation in white and brown adipose tissue(WAT and BAT),and liver during the SAAR diet refeeding state,leading to decreased de novo lipogenesis.Enhanced lipolysis and fatty acid oxidation were observed in the heart,brain,BAT,lungs,etc.The reintroduction of methionine or cystine negated these metabolic benefits.Further 13C and 2H tracing experiments indicated that cystine,rather than its derivatives like taurine or H2S,directly regulates adiposity.In a high-fat diet model,SAAR diet led to sustained fat mass reduction,regardless of the timing of intervention.Additionally,cystine levels correlated positively with body mass index(BMI)and total triglycerides in diabetic patients.Our findings highlight SAAR diet as a promising strategy for long-term weight control by modulating systemic glucose and lipid metabolism homeostasis.展开更多
In mid-September 2013, PM2.5 samples were collected at six sites in Nanchang, Jiangxi Province, China, to quantify nine water-soluble ions （Ca2＋, Mg2＋, K＋, Na＋, NH4＋, SO42-, Cl-, F , NO3 ）, 29 trace elements （...In mid-September 2013, PM2.5 samples were collected at six sites in Nanchang, Jiangxi Province, China, to quantify nine water-soluble ions （Ca2＋, Mg2＋, K＋, Na＋, NH4＋, SO42-, Cl-, F , NO3 ）, 29 trace elements （Ba, Zn, Pb, Ni, Mo, Cr, Cu, Sr, Sb, Rb, Cd, Bi, Zr, V, Ga, Li, Y, Nb, W, Cs, Tl, Sc, Co, U, Hf, In, Re, Be, and Ta）, and to characterize Pb isotopic ratios （^207pb/^206pb, ^208pb/^206pb, and ^207pb/^204pb） for identifying the main source（s） of Pb. The results showed that the average daily PM2.5 concentration （53.16 ± 24.17） Dg/m3 was within the secondary level of the Chinese ambient air quality standard. The combined concentrations of SO42-, NH4＋, and NO3- to total measured water-soluble ion concentrations in PM2.5 ranged from 79.40% to 95.18%, indicating that anthropogenic sources were significant. Coal combustion and vehicle emissions were both contributors to PM2.5 based on the NO3-/SO4^2- ratios. Wushu School experienced the lowest concentrations of PM2.s and most trace elements among the six sampling sites. Enrichment factor results showed that TI, Cr, In, Cu, Zn, Pb, Bi, Ni, Sb, and Cd in PM2.5 were affected by anthropogenic activities. Cluster analysis suggested that Cd, Sb, Pb, Re, Zn, Bi, Cs, Tl, Ga, and In were possibly related to coal combustion and vehicle exhaust, while Ni, Nb, Cr, and Mo may have originated from metal smelting. Pb isotopic tracing showed that coal dust, cement dust, road dust and construction dust were the major Pb sources in PM2.5 in Nanchang. Combined, these sources contributed an average of 72.51% of the Pb measured, while vehicle exhaust accounted for 27.49% of Pb based on results from a binary Pb isotope mixed model,展开更多
Solar driven carbon dioxide(CO_(2))recycling into hydrocarbon fuels using semiconductor photocatalysts offers an ideal energy conversion pathway to solve both the energy crisis and environmental degradation problems.H...Solar driven carbon dioxide(CO_(2))recycling into hydrocarbon fuels using semiconductor photocatalysts offers an ideal energy conversion pathway to solve both the energy crisis and environmental degradation problems.However,the ubiquitous presence of carbonaceous contaminants in photocatalytic CO_(2) reduction system and the inferior yields of hydrocarbon fuels raise serious concerns about the reliability of the reported experimental results.Here in this perspective,we focus on the accurate assessment of the CO_(2) reduction products,systemically discuss the possible sources of errors in the product quantification,elaborate the common mistakes spread in the analysis of reaction products obtained in 13CO_(2) labelling experiments,and further propose reliable protocols for reporting the results of these isotopic tracing experiments.Moreover,the challenges and cautions in the precise measurement of O_(2) evolution rate are also depicted,and the amplification of the concentration of O_(2) in photoreactors well above the limit of detection is still demonstrated to be the most effective solution to this troublesome issue.We hope the viewpoints raised in this paper will help to assessment the reliability of the reported data in future,and also benefit the beginners that intend to dive in the photocatalytic CO_(2) reduction area.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42341102 and 42102288)the Forestry Science and Technology Innovation Project of Shaanxi Province(No.SXLK2023–02–1)+1 种基金the Fundamental Research Funds for the Central Universities,China(No.300102263401)the Fundamental Research Funds for the Central Universities,China(No.300102294905).
文摘Rivers and groundwater are the main water sources for cities.The mutual transformation between river water and groundwater makes it difficult to accurately evaluate and rationally utilize water resources.Scientifically quantifying the interaction of surface water and groundwater remains challenging.Taking Chan River Basin as an example,this study aimed to determine the interconversion processes of groundwater and surface water by hydrogeochemical genesis mechanism analysis,isotope tracing,and end-member mixing analysis(EMMA).28 surface water samples and 23 groundwater samples were collected and analyzed during December 2023 and January 2024.Results showed thewater bodies in the study area were dominated by the HCO_(3)-Ca,HCO_(3)-Ca·Mg·Na,and HCO_(3)·SO_(4)-Ca·Na types,with hydrogeochemical processes controlled by the weathering and dissolution of both carbonate and silicate rock minerals.The river water in the upper reaches of the study area is mainly recharged by groundwater,with the average recharge ratio of 54.10%.Similarly,river water is still recharged by groundwater in the middle reaches,the average recharge ratio changes to 28.61%.In the downstream area,where Xi’an City located,due to the heavy exploitation of groundwater,the river water recharges to groundwater with an average recharge ratio of 85.23%,although in the immediate middle reaches,groundwater still replenishes surface waterwith a recharge rate of 75.00%.The results laid the bases for the reasonable utilization of water resources in the Chan River Basin and also served as a reference in other regions of the world.
文摘Three different types of gold and silver deposits in Zhejiang Province(Huangshan gold deposit, Zhilingtou gold-silver deposit and Haoshi silver deposit) showmarked differences in lead and strontium isotopic composition, suggesting three differentsources and geneses of these deposits. The Huangshan gold deposit features low initial Srisotope ratios and low μ values or low content of radiogenic Pb and its ore-forming materialscame primarily from the upper mantle; the Zhilingtou gold-silver deposit shows high initial Srisotope ratios and high μ values or high content of radiogenic Pb and the ore-forming materialswere derived mainly from the upper crust; and the Haoshi silver deposit has its Pb and Srisotope ratios between the above two cases with the ore-forming materials stemming from boththe mantle and the crust. The characteristic Pb isotopic composition may serve as an indicatorfor prospecting for different types of ore deposits.
文摘Using Na15NO3 and 15NH4Cl as tracer, we studied the transfer of 15N along the food chain composed oforganisms such as Platymonas subcordiformis, Artemia salina, Penaeus penicillatus and Liza carinatus . The abundanceand atomic percentage of 15N in each organism, as well as the transfer of 15N among different biological phases weremeasured. Results show that, in the nutrient transfer from low level to high level along the md chain in the mediaof 15NH4Cl, the transfer rate of Artemia salina→Liza carinatus exceeded 3% and was higher than that in Na15NO3; the accumulation of 15N in the bodies of Liza carinatus with 15NH4Cl as media was also higher than that withNa 15NO3 as media.
基金supported by the National Natural Science Foundation of China(Nos.U2040201,32201334,92251304,and 42271126),the Project of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou,No.GML20220017),the Outstanding Postdoctoral Project in Jiangsu Province(No.2022ZB455),the Chinese Postdoctoral Science Foundation(No.2022M721661)and the Project of State Key Laboratory of Lake Science and Environment(No.2022SKL019).
文摘Anaerobic ammonium oxidation coupled to iron(III)reduction(Feammox)process has recently been recognized as an important pathway for removing ammonium in various natural habitats.However,our understanding for Feammox in river–estuary continuum is limited.In this study,stable isotope tracers and high-throughput amplicon sequencing were employed to determine Feammox rates and identify associated microbial communities in sediments along the Yangtze river–estuary continuum.Feammox rates averaged 0.0058±0.0069 mg N/(kg·d)and accounted for approximately 22.3%of the ammonium removed from the sediments.Sediment Fe(III),ammonium(NH_(4)^(+)),total organic carbon(TOC),and pH were identified as important factors influencing Feammox rates.Additionally,Spirochaeta,Caldilineaceae_uncultured,and Ignavibacterium were found potentially associated with Feammox,which had not been documented as Feammox-associated microbial taxa previously.This study demonstrates that Feammox plays a vital role in ammonium removal within the Yangtze river–estuary continuum,providing greater insight into nitrogen removal and cycling in aquatic ecosystems.
基金Yunnan Major Scientific and Technological Project(grant no.202202AG050006)National Natural Science Foundation project(grant No.42272078)Yunnan Fundamental Research Project(grant No.202401CF070094).
文摘The Saxi tungsten deposit,located in the Laojunshan ore district of southeastern Yunnan Province,is a significant W-polymetallic deposit.The origins of tungstenbearing pegmatite dikes and quartz vein mineralization in the Saxi deposit remain poorly understood.This study employs in situ U-Pb dating of apatite from the altered granite,along with trace element and S-Pb isotopic analysis of arsenopyrite,to investigate the timing,source of ore-forming fluids and the mechanisms of tungsten enrichment.The apatite in the altered granite yields a U-Pb age of 147.0±4.0 Ma,indicating magmatic activity during the Early Cretaceous.Three generations of arsenopyrite(Apy)are identified:Apy-1 in the altered granite,Apy-2 in the pegmatite dikes and Apy-3 in the quartz veins.The S/Fe ratios for Apy-1,Apy-2 and Apy-3 range from 0.98 to 1.09,0.89 to 0.92 and 0.86 to 1.02,respectively(average 0.97),suggesting a magmatic-hydrothermal origin.Sulfur isotope values(δ^(34)S=4.29‰-8.11‰)indicate that it was likely sourced from deep magmatic-hydrothermal fluids.Lead isotopic compositions of arsenopyrite suggest that the granitic parental magma is derived from the upper crust.These findings point to a magmatic-hydrothermal origin for the vein-type tungsten mineralization,linked to a concealed magmatichydrothermal system in the Early Cretaceous.
基金This research was supported by the National Natural Science Foundation of China （90502007, 30270230） the Program for New Century Excellent Talents in University, China （NCET-04-0955）the United Scholar＇s Item of Talent Training Program in West China of CAS and the Program for 0utstanding Talents in Northwest A ＆ F University.
文摘Plant roots dynamics responses to elevated atmospheric CO2 concentration, increased temperature and changed precipitation can be a key link between plant growth and long-term changes in soil organic matter and ecosystem carbon balance. This paper reviews some experiments and hypotheses developed in this area, which mainly include plant fine roots growth, root turnover, root respiration and other root dynamics responses to elevated CO2 and global climate change. Some recent new methods of studying root systems were also discussed and summarized. It holds herein that the assemblage of information about root turnover patterns, root respiration and other dynamic responses to elevated atmospheric CO2 and global climatic change can help to better understand and explore some new research areas. In this paper, some research challenges in the plant root responses to the elevated CO2 and other environmental factors during global climate change were also demonstrated.
基金supported by grants from the National Natural Science Foundation of China(Grant No.:81803496)the CAMS Innovation Fund for Medical Sciences(Grant No.:2016-I2M-3-016)the Applications and Core Technology University Research(ACT-UR,Grant No.:4084)。
文摘There is an urgent need to elucidate the pathogenesis of myocardial ischemia(MI)and potential drug treatments.Here,the anti-MI mechanism and material basis of Ginkgo biloba L.extract(GBE)were studied from the perspective of energy metabolism flux regulation.Metabolic flux analysis(MFA)was performed to investigate energy metabolism flux disorder and the regulatory nodes of GBE components in isoproterenol(ISO)-induced ischemia-like cardiomyocytes.It showed that[U-13 C]glucose derived m+2 isotopologues from the upstream tricarboxylic acid(TCA)cycle metabolites were markedly accumulated in ISO-injured cardiomyocytes,but the opposite was seen for the downstream metabolites,while their total cellular concentrations were increased.This indicates a blockage of carbon flow from glycolysis and enhanced anaplerosis from other carbon sources.A Seahorse test was used to screen for GBE components with regulatory effects on mitochondrial aerobic respiratory dysfunction.It showed that bilobalide protected against impaired mitochondrial aerobic respiration.MFA also showed that bilobalide significantly modulated the TCA cycle flux,reduced abnormal metabolite accumulation,and balanced the demand of different carbon sources.Western blotting and PCR analysis showed that bilobalide decreased the enhanced expression of key metabolic enzymes in injured cells.Bilobalide’s efficacy was verified by in vivo experiments in rats.This is the first report to show that bilobalide,the active ingredient of GBE,protects against MI by rescuing impaired TCA cycle flux.This provides a new mechanism and potential drug treatment for MI.It also shows the potential of MFA/Seahorse combination as a powerful strategy for pharmacological research on herbal medicine.
基金funded by the National Natural Science Foundation of China(41907175)the Open Fund of Key Laboratory(WSRCR-2023-01)the project of the China Geological Survey(DD20230459).
文摘Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.
基金National Key Basic Research Program of China（973 Program）,No.2010CB950904 National Natural Science Foundation of China,No.40971223 Knowledge Innovation Project of CAS,No.KZCX2-EW-306
文摘In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground and diverse, or even irregular, operations in sampling and testing procedures, CRI determination is usually faced with many difficulties and uncertainties. In addition, more difficulties occur in an investigation of a large-scale region because of time constraints and measurement cost limitations. In this study, traditional CRI acquiring methods were summarized first, and then a new complex scheme was established, involving seven core steps and coupling the model estimate and sample measurement. The above CRI determination methodology was implemented in the central-eastern Inner Mongolia Plateau. The case study results showed that the CRI in the dark chestnut soil sub-region, located in the east and south of Xing＇an City, exhibited 2447 Bq·m–2; the CRI in the aeolian sandy soil sub-region, positioned in the south central Tongliao City and central Chifeng City, showed 2430 Bq·m–2; the CRI in the sandy chernozem soil sub-region, situated in the northwestern Chifeng City, presented 2384 Bq·m–2; and the CRI in the chestnut soil sub-region, in the southern Xilin Gol City, was 2368 Bq·m–2. The newly proposed CRI determination scheme was proved effective, and the determined CRI plots and CRI values were convincing. The methodology offered a framework for 137 Cs tracing studies in large-scale regions or long-distance transects.
基金Supported by Open Fund of State Key Laboratory of Loess and Quaternary Geology(SKLLQG1607)Innovative Entrepreneurial Project of College Students(201712709011)
文摘With low concentration of stable lead isotope as the tracer, using inductively coupled plasma mass spectrometry （ICP-MS）, the lead absorption of tea plants as well as the distribution and migration pattern of lead in plants under different pH environments and spraying introduction of lead sources were studied through pot trial. The results showed that tea plants were very sensitive to atmospheric lead source pollution; atmospheric lead source pollution had a tendency of moving up to the top （bud） ; low pH conditions enhanced lead absorption of plants and promoted upward migration of lead in plants. The experimental method is closer to the actual situation that plants are exposed to low concentration pollution, and could distinguish experimentally introduced lead source from environmentally introduced lead source.
文摘Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite were close to the δ13CPDB value of original magma; δ30Si values of the samples at the ore-forming stage were close to the δ30Si value range of magma, δ30Si values of partial samples were far away from it; Cu isotopic compositions of massive chalcopyrite formed at the early ore-forming stage are higher than that of veinal chalcopyrite formed at the later ore-forming stage. The results show that ore-forming materials were mainly derived from the porphyry body, and part of them were from wall rock materials.
基金supported by the National Natural Science Foundation of China(No.21927808 and No.81974500)Chinese Academy of Medical Science(CAMS)Innovation Fund for Medical Sciences(CIFMS,No.2022-I2M-2-002 and 2021-1I2M-028,China)。
文摘Deconvolution of potential drug targets of the central nervous system(CNS)is particularly challenging because of the complicated structure and function of the brain.Here,a spatiotemporally resolved metabolomics and isotope tracing strategy was proposed and demonstrated to be powerful for deconvoluting and localizing potential targets of CNS drugs by using ambient mass spectrometry imaging.This strategy can map various substances including exogenous drugs,isotopically labeled metabolites,and various types of endogenous metabolites in the brain tissue sections to illustrate their microregional distribution pattern in the brain and locate drug action-related metabolic nodes and pathways.The strategy revealed that the sedative-hypnotic drug candidate YZG-331 was prominently distributed in the pineal gland and entered the thalamus and hypothalamus in relatively small amounts,and can increase glutamate decarboxylase activity to elevateγ-aminobutyric acid(GABA)levels in the hypothalamus,agonize organic cation transporter 3 to release extracellular histamine into peripheral circulation.These findings emphasize the promising capability of spatiotemporally resolved metabolomics and isotope tracing to help elucidate the multiple targets and the mechanisms of action of CNS drugs.
基金supported by grants from the National Science Foundation of China(32271354 to L.Y.)the National Key R&D Program of China(2022YFA1305200 to L.Y.)+3 种基金the Non-profit Central Research Institute Fund of the Chinese Academy of Medical Sciences(2021-RC350-008 to L.W.)the Talent Plan of Shanghai Branch-Chinese Academy of Sciences(CASSHB-QNPD-2023-011 to L.Y.)the State Key Laboratory Special Fund(2060204 to L.W.)the Beijing Natural Science Foundation(Z240014 to L.W.)。
文摘Diet interventions such as calorie restriction or time-restricted feeding offer potential for weight management,but long-term success is often hindered by poor adherence due to the rewarding effects of sugars.In this study,we demonstrate that sulfur amino acid restriction(SAAR)diets promote rapid fat loss without impairing appetite and physiological locomotion,outperforming diets with restricted branched-chain amino acids.Weekly cycling of SAAR diets preserves metabolic benefits,such as reduced fat mass and improved glucose sensitivity.Metabolic analysis and in vivo isotope tracing revealed a shift toward carbohydrate oxidation in white and brown adipose tissue(WAT and BAT),and liver during the SAAR diet refeeding state,leading to decreased de novo lipogenesis.Enhanced lipolysis and fatty acid oxidation were observed in the heart,brain,BAT,lungs,etc.The reintroduction of methionine or cystine negated these metabolic benefits.Further 13C and 2H tracing experiments indicated that cystine,rather than its derivatives like taurine or H2S,directly regulates adiposity.In a high-fat diet model,SAAR diet led to sustained fat mass reduction,regardless of the timing of intervention.Additionally,cystine levels correlated positively with body mass index(BMI)and total triglycerides in diabetic patients.Our findings highlight SAAR diet as a promising strategy for long-term weight control by modulating systemic glucose and lipid metabolism homeostasis.
基金This work was supported by the National Natural Science Foun- dation of China （21377042, 21477042） and the Natural Science Foundation of Fujian Province （2016 J01065）. The authors express their heartfelt thanks to the colleagues who participated in the sampiing work. Mr. James Ing, a native English speaker from the UK is gratefully acknowledged for reviewing this paper prior to resub- mission. We thank the anonymous reviewers for their constructive comments.
文摘In mid-September 2013, PM2.5 samples were collected at six sites in Nanchang, Jiangxi Province, China, to quantify nine water-soluble ions （Ca2＋, Mg2＋, K＋, Na＋, NH4＋, SO42-, Cl-, F , NO3 ）, 29 trace elements （Ba, Zn, Pb, Ni, Mo, Cr, Cu, Sr, Sb, Rb, Cd, Bi, Zr, V, Ga, Li, Y, Nb, W, Cs, Tl, Sc, Co, U, Hf, In, Re, Be, and Ta）, and to characterize Pb isotopic ratios （^207pb/^206pb, ^208pb/^206pb, and ^207pb/^204pb） for identifying the main source（s） of Pb. The results showed that the average daily PM2.5 concentration （53.16 ± 24.17） Dg/m3 was within the secondary level of the Chinese ambient air quality standard. The combined concentrations of SO42-, NH4＋, and NO3- to total measured water-soluble ion concentrations in PM2.5 ranged from 79.40% to 95.18%, indicating that anthropogenic sources were significant. Coal combustion and vehicle emissions were both contributors to PM2.5 based on the NO3-/SO4^2- ratios. Wushu School experienced the lowest concentrations of PM2.s and most trace elements among the six sampling sites. Enrichment factor results showed that TI, Cr, In, Cu, Zn, Pb, Bi, Ni, Sb, and Cd in PM2.5 were affected by anthropogenic activities. Cluster analysis suggested that Cd, Sb, Pb, Re, Zn, Bi, Cs, Tl, Ga, and In were possibly related to coal combustion and vehicle exhaust, while Ni, Nb, Cr, and Mo may have originated from metal smelting. Pb isotopic tracing showed that coal dust, cement dust, road dust and construction dust were the major Pb sources in PM2.5 in Nanchang. Combined, these sources contributed an average of 72.51% of the Pb measured, while vehicle exhaust accounted for 27.49% of Pb based on results from a binary Pb isotope mixed model,
基金the Basic Science Center Project for Ordered Energy Conversion of the National Natural Science Foundation of China(No.51888103).
文摘Solar driven carbon dioxide(CO_(2))recycling into hydrocarbon fuels using semiconductor photocatalysts offers an ideal energy conversion pathway to solve both the energy crisis and environmental degradation problems.However,the ubiquitous presence of carbonaceous contaminants in photocatalytic CO_(2) reduction system and the inferior yields of hydrocarbon fuels raise serious concerns about the reliability of the reported experimental results.Here in this perspective,we focus on the accurate assessment of the CO_(2) reduction products,systemically discuss the possible sources of errors in the product quantification,elaborate the common mistakes spread in the analysis of reaction products obtained in 13CO_(2) labelling experiments,and further propose reliable protocols for reporting the results of these isotopic tracing experiments.Moreover,the challenges and cautions in the precise measurement of O_(2) evolution rate are also depicted,and the amplification of the concentration of O_(2) in photoreactors well above the limit of detection is still demonstrated to be the most effective solution to this troublesome issue.We hope the viewpoints raised in this paper will help to assessment the reliability of the reported data in future,and also benefit the beginners that intend to dive in the photocatalytic CO_(2) reduction area.
