A protocol was established for simultaneous measurements of zircon U-Pb ages and trace elements by LA-ICP-MS at spot sizes of 16 32 μm.This was accomplished by introducing N 2 into ICP to increase the sensitivity.The...A protocol was established for simultaneous measurements of zircon U-Pb ages and trace elements by LA-ICP-MS at spot sizes of 16 32 μm.This was accomplished by introducing N 2 into ICP to increase the sensitivity.The obtained U-Pb ages for zircon standards GJ-1,TEMORA and SK10-2 are consistent with the preferred values within about 1% uncertainty (2σ) by simple external calibration against zircon standard 91500.Different data reduction softwares could yield different uncertainties for calculation of U-Pb ages.The commercially available program GLITTER4.4 could apply an improper uncertainty calculation strategy,but it may yield artificial high precisions for single analyses.Our trace element analyses indicate that Si is not an ideal internal standard for zircon when calibrated against the NIST glasses.Calibration against the NIST glasses using Si as an internal standard,a systematic deviation of 10% 30% was found for most trace elements including Zr.However,the trace element compositions of zircon can be accurately measured by calibration against multiple reference materials with natural compositions (e.g.,BCR-2G,BHVO-2G and BIR-1G),or calibration against NIST SRM 610 and using Zr as an internal standard.Analyses of two pieces of GJ-1 demonstrate that it is relatively homogenous for most trace elements (except for Ti).展开更多
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with stand...Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change展开更多
Using the in situ zircon U-Pb dating method of LA-ICPMS, we analyzed the 31 Ma old SHRIMP U-Pb age of the Yongsheng nepheline syenite from southern Jilin Province under different spot sizes. The obtained ages are comp...Using the in situ zircon U-Pb dating method of LA-ICPMS, we analyzed the 31 Ma old SHRIMP U-Pb age of the Yongsheng nepheline syenite from southern Jilin Province under different spot sizes. The obtained ages are comparable with that of SHRIMP in both accuracy and precision. The age is also identical to that of the Yinmawanshan gabbro from the Liaodong Peninsula within error. Both the Yongsheng nepheline syenite and the Yinmawanshan gabbro represent the youngest known exposed intrusions in northeastern and even eastern China. The results indicate the Eocene mantle-derived magmatic underplating, and the rapid crustal uplifting of this region since 30 Ma. The analyses also document extremely high LREE concentrations and relatively flat REE patterns for the zircons from the Yongsheng nepheline syenite, which represent a new type of zircon REE pattern.展开更多
Intelligent manufacturing is a general concept that is under continuous development. It can be categorized into three basic paradigms: digital manufacturing, digital-networked manufacturing, and newgeneration intelli...Intelligent manufacturing is a general concept that is under continuous development. It can be categorized into three basic paradigms: digital manufacturing, digital-networked manufacturing, and newgeneration intelligent manufacturing. New-generation intelligent manufacturing represents an indepth integration of new-generation artificial intelligence (AI) technology and advanced manufacturing technology. It runs through every link in the full life-cycle of design, production, product, and service. The concept also relates to the optimization and integration of corresponding systems; the continuous improvement of enterprises' product quality, performance, and service levels; and reduction in resources consumption. New-generation intelligent manufacturing acts as the core driving force of the new indus- trial revolution and will continue to he the main pathway for the transformation and upgrading of the manufacturing industry in the decades to come. Human-cyher-physical systems (HCPSs) reveal the tech- nological mechanisms of new-generation intelligent manufacturing and can effectively guide related the- oretical research and engineering practice. Given the sequential development, cross interaction, and iterative upgrading characteristics of the three basic paradigms of intelligent manufacturing, a technol- ogy roadmap for "parallel promotion and integrated development" should he developed in order to drive forward the intelligent transformation of the manufacturing industry in China.展开更多
China faces the greatest challenge from stroke in the world.The death rate for cerebrovascular diseases in China was 149.49 per 100000,accounting for 1.57 million deaths in 2018.It ranked third among the leading cause...China faces the greatest challenge from stroke in the world.The death rate for cerebrovascular diseases in China was 149.49 per 100000,accounting for 1.57 million deaths in 2018.It ranked third among the leading causes of death behind malignant tumours and heart disease.The age-standardised prevalence and incidence of stroke in 2013 were 1114.8 per 100000 population and 246.8 per 100000 person-years,respectively.According to the Global Burden of Disease Study 2017,the years of life lost(YLLs)per 100000 population for stroke increased by 14.6%;YLLs due to stroke rose from third highest among all causes in 1990 to the highest in 2017.The absolute numbers and rates per 100000 population for all-age disability-adjusted life years(DALYs)for stroke increased substantially between 1990 and 2017,and stroke was the leading cause of all-age DALYs in 2017.The main contributors to cerebrovascular diseases include behavioural risk factors(smoking and alcohol use)and pre-existing conditions(hypertension,diabetes mellitus,dyslipidaemia and atrial fibrillation(AF)).The most prevalent risk factors among stroke survivors were hypertension(63.0%-84.2%)and smoking(31.7%-47.6%).The least prevalent was AF(2.7%-7.4%).The prevalences for major risk factors for stroke are high and most have increased over time.Based on the latest national epidemiological data,26.6%of adults aged≥15 years(307.6 million adults)smoked tobacco products.For those aged≥18 years,age-adjusted prevalence of hypertension was 25.2%;adjusted prevalence of hypercholesterolaemia was 5.8%;and the standardised prevalence of diabetes was 10.9%.For those aged≥40 years,the standardised prevalence of AF was 2.31%.Data from the Hospital Quality Monitoring System showed that 3010204 inpatients with stroke were admitted to 1853 tertiary care hospitals during 2018.Of those,2466785(81.9%)were ischaemic strokes(ISs);447609(14.9%)were intracerebral haemorrhages(ICHs);and 95810(3.2%)were subarachnoid haemorrhages(SAHs).The average age of patients admitted was 66 years old,and展开更多
The North China Craton (NCC) is a classical example of ancient destroyed cratons.Since the initiation of the North China Craton Destruction Project by the National Natural Science Foundation of China,numerous studies ...The North China Craton (NCC) is a classical example of ancient destroyed cratons.Since the initiation of the North China Craton Destruction Project by the National Natural Science Foundation of China,numerous studies have been conducted on the timing,scale,and mechanism of this destruction through combined interdisciplinary research.Available data suggest that the destruction occurred mainly in the eastern NCC,whereas the western NCC was only locally modified.The sedimentation,magmatic activities and structural deformation after cratonization at ~1.8 Ga indicate that the NCC destruction took place in the Mesozoic with a peak age of ca 125 Ma.A global comparison suggests that most cratons on Earth are not destroyed,although they have commonly experienced lithospheric thinning;destruction is likely to occur only when the craton has been disturbed by oceanic subduction.The destruction of the NCC was coincident with globally active plate tectonics and high mantle temperatures during the Cretaceous.The subducted Pacific slab destabilized mantle convection beneath the eastern NCC,which resulted in cratonic destruction in the eastern NCC.Delamination and/or thermal-mechanical-chemical erosion resulted from the destabilization of mantle convection.展开更多
In January 2013, a long-lasting episode of severe haze occurred in central and eastern China, and it attracted attention from all sectors of society. The process and evolution of haze pollution episodes were observed ...In January 2013, a long-lasting episode of severe haze occurred in central and eastern China, and it attracted attention from all sectors of society. The process and evolution of haze pollution episodes were observed by the "Forming Mechanism and Con- trol Strategies of Haze in China" group using an intensive aerosol and trace gases campaign that simultaneously obtained data at 11 ground-based observing sites in the CARE-China network. The characteristics and formation mechanism of haze pollu- tion episodes were discussed. Five haze pollution episodes were identified in the Beijing-Tianjin-Hebei (Jing-Jin-Ji) area; the two most severe episodes occurred during 9-15 January and 25-31 January. During these two haze pollution episodes, the maximum hourly PMz5 mass concentrations in Beijing were 680 and 530 ~tg m-3, respectively. The process and evolution of haze pollution episodes in other major cities in the Jing-Jin-Ji area, such as Shijiazhuang and Tianjin were almost the same as those observed in Beijing. The external cause of the severe haze episodes was the unusual atmospheric circulation, the depres- sion of strong cold air activities and the very unfavorable dispersion due to geographical and meteorological conditions. How- ever, the internal cause was the quick secondary transformation of primary gaseous pollutants to secondary aerosols, which contributed to the "explosive growth" and "sustained growth" of PM2.5. Particularly, the abnormally high amount of nitric ox- ide (NOx) in the haze episodes, produced by fossil fuel combustion and vehicle emissions, played a direct or indirect role in the quick secondary transformation of coal-burning sulphur dioxide (SO2) to sulphate aerosols. Furthermore, gaseous pollutants were transformed into secondary aerosols through heterogeneous reactions on the surface of fine particles, which can change the particle's size and chemical composition. Consequently, the proportion of secondary inorganic ions, such as sulphate and nitrate, gradually incr展开更多
Liquid chromatography-mass spectrometry (LC-MS)-based metabolomics has been facilitated by the con- struction of MSz spectral tag (MS2T) library from the total scan ESI MS/MS data, and the development of widely ta...Liquid chromatography-mass spectrometry (LC-MS)-based metabolomics has been facilitated by the con- struction of MSz spectral tag (MS2T) library from the total scan ESI MS/MS data, and the development of widely targeted metabolomics method using MS/MS data gathered from authentic standards. In this report, a novel strategy called step- wise multiple ion monitoring-enhanced product ions (stepwise MIM-EPI) was developed to construct the MS2T library, in which stepwise MIM was used as survey scans to trigger the acquisition of EPI. A total number of 698 (almost) non- redundant metabolites with MS2 spectra were obtained, of which 135 metabolites were identified/annotated. Integrating the data gathered from our MS2T library and other available multiple reaction monitoring (MRM) information, a widely targeted metabolomics method was developed to quantify 277 metabolites, including some phytohormones. Evaluation of the dehydration responses and natural variations of these metabolites in rice leaf not only suggested the coordinated regulation of abscisic acid (ABA) with metabolites such as serotonin derivative(s), polyamine conjugates under drought stress, but also revealed some C-glycosylated flavones as the potential markers for the discrimination of indica and japonica rice subspecies. The new MS2T library construction and widely targeted metabolomics strategy could be used as a tool for rice functional genomics.展开更多
As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, envir...As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations.展开更多
The outbreak of the 2019-nCoV infection began in December 2019 in Wuhan,Hubei province,and rapidly spread to many provinces in China as well as other countries.Here we report the epidemiological,clinical,laboratory,an...The outbreak of the 2019-nCoV infection began in December 2019 in Wuhan,Hubei province,and rapidly spread to many provinces in China as well as other countries.Here we report the epidemiological,clinical,laboratory,and radiological characteristics,as well as potential biomarkers for predicting disease severity in 2019-nCoV-infected patients in Shenzhen,China.All 12 cases of the 2019-nCoV-infected patients developed pneumonia and half of them developed acute respiratory distress syndrome (ARDS).The most common laboratory abnormalities were hypoalbuminemia,lymphopenia,decreased percentage of lymphocytes (LYM) and neutrophils (NEU),elevated C-reactive protein (CRP) and lactate dehydrogenase (LDH),and decreased CD8 count.The viral load of 2019-nCoV detected from patient respiratory tracts was positively linked to lung disease severity.ALB,LYM,LYM (%),LDH,NEU (%),and CRP were highly correlated to the acute lung injury.Age,viral load,lung injury score,and blood biochemistry indexes,albumin (ALB),CRP,LDH,LYM (%),LYM,and NEU (%),may be predictors of disease severity.Moreover,the Angiotensin Ⅱlevel in the plasma sample from 2019-nCoV infected patients was markedly elevated and linearly associated to viral load and lung injury.Our results suggest a number of potential diagnosis biomarkers and angiotensin receptor blocker (ARB) drugs for potential repurposing treatment of 2019-nCoV infection.展开更多
There exist differences in the epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selections between gastric cancer patients from the Eastern and ...There exist differences in the epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selections between gastric cancer patients from the Eastern and Western countries.The Chinese Society of Clinical Oncology(CSCO)has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually.Taking into account regional differences,giving full consideration to the accessibility of diagnosis and treatment resources,these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China.The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis,treatment,follow-up,and screening of gastric cancer.Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines,this updated guideline integrates the results ofmajor clinical studies from China and overseas for the past year,focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations.For the comprehensive treatment of non-metastatic gastric cancer,attentions were paid to neoadjuvant treatment.The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated.For the comprehensive treatment of metastatic gastric cancer,recommendations for immunotherapy were included,and immune checkpoint inhibitors fromthird-line to the first-line of treatment for different patient groups with detailed notes are provided.展开更多
Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of...Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21 st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period.展开更多
Granite is one of the most important components of the continental crust on our Earth; it thus has been an enduring studied subject in geology. According to present knowledge, granite shows a great deal of heterogenei...Granite is one of the most important components of the continental crust on our Earth; it thus has been an enduring studied subject in geology. According to present knowledge, granite shows a great deal of heterogeneity in terms of its texture,structure, mineral species and geochemical compositions at different scales from small dike to large batholith. However, the reasons for these variations are not well understood although numerous interpretations have been proposed. The key point of this debate is whether granitic magma can be effectively differentiated through fractional crystallization, and, if so, what kind of crystallization occurred during the magmatic evolution. Although granitic magma has high viscosity because of its elevated SiO2 content, we agree that fractional crystallization is effectively processed during its evolution based on the evidence from field investigation,mineral species and its chemical variations, and geochemical compositions. These data indicate that crystal settling by gravitation is not the only mechanism dominating granitic differentiation. On the contrary, flow segregation or dynamic sorting may be more important. Accordingly, granite can be divided into unfractionated, fractionated(including weakly fractionated and highly fractionated) and cumulated types, according to the differentiation degree. Highly fractionated granitic magmas are generally high in primary temperature or high with various volatiles during the later stage, which make the fractional crystallization much easier than the common granitic melts. In addition, effective magmatic differentiation can be also expected when the magma emplaced along a large scale of extensional structure. Highly fractionated granitic magma is easily contaminated by country rocks due to its relatively prolonged crystallization time. Thus, granites do not always reflect the characteristics of the source areas and the physical and chemical conditions of the primary magma. We proposed that highly fractionated granites are an important sig展开更多
China is one of the countries with the highest incidence of gastric cancer.There are differences in epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and ...China is one of the countries with the highest incidence of gastric cancer.There are differences in epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selection between gastric cancer patients from the Eastern and Western countries.Non-Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer patients.The Chinese Society of Clinical Oncology(CSCO)arranged for a panel of senior experts specializing in all sub-specialties of gastric cancer to compile,discuss,and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence-based medicine in China and abroad.By referring to the opinions of industry experts,taking into account of regional differences,giving full consideration to the accessibility of diagnosis and treatment resources,these experts have conducted experts’consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes.This guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis,comprehensive treatment,and follow-up visits for gastric cancer.展开更多
The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of trans...The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).展开更多
AIM: To identify the property of dendritic cells (DCs) of peripheral blood monocytes (PBMC) in patients with chronic HBV infection. METHODS: Twenty patients with persistent HBV infection were included in this study, 1...AIM: To identify the property of dendritic cells (DCs) of peripheral blood monocytes (PBMC) in patients with chronic HBV infection. METHODS: Twenty patients with persistent HBV infection were included in this study, 10 healthy subjects being used as a control group. The peripheral blood mononuclear cells (PBMC) of T cell-depleted populations were incubated and induced into mature dendritic cells in the RPMI-1640 medium in the presence of cytokines GM-CSF, IL-4, FLt-3,TNF-alpha and 100mL.L(-1 )of fetal calf serum for a total of 10-12 days. The expressions of surface markers on DCs were evaluated using flow cytometric analysis. ELISA method was used to determine the cytokine levels of interleukin-12 (IL-12) and IL-10 in the supernatant produced by DCs. For detection of the stimulatory capacity of DCs to T cell proliferation, mytomycin C-treated DC were incubated with allogenic T cells. RESULTS: A typical morphology of mature DCs from healthy subjects and HBV-infected patients was induced in in vitro incubation, but the proliferation ability and cellular number of DCs from HBV-infected patients significantly decreased compared with healthy individuals. In particular, the expression levels of HLA-DR, CD80 (B7-1) and CD86 (B7-2) on DC surface from patients were also lower than that from healthy individuals (0.46 vs 0.92 for HLA-DR, 0.44 vs 0.88 for CD80 and 0.44 vs 0.84 for CD86,P【0.05). The stimulatory capacity and production of IL-12 of DCs from patients in allogenic mixed lymphocyte reaction (AMLR) significantly decreased, but the production level of nitric oxide (NO) by DCs simultaneously increased compared with healthy subjects (86 +/- 15 vs 170 +/- 22 micromol.L(-1), P 【0.05). CONCLUSION: The patients with chronic HBV infection have the defective function and immature phenotype of dendritic cells, which may be associated with the inability of efficient presentation of HBV antigens to host immune system for the clearance of HBV.展开更多
MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular si...MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.展开更多
基金supported by the National Natural Science Foundation of China (GrantNos. 40821061,90914007,40576030 and 90714010)the State Administration of Foreign Expert Affairs of China (Grant No. B07039)the Special Fund for Basic Scientific Research of Central Colleges,China University of Geosciences
文摘A protocol was established for simultaneous measurements of zircon U-Pb ages and trace elements by LA-ICP-MS at spot sizes of 16 32 μm.This was accomplished by introducing N 2 into ICP to increase the sensitivity.The obtained U-Pb ages for zircon standards GJ-1,TEMORA and SK10-2 are consistent with the preferred values within about 1% uncertainty (2σ) by simple external calibration against zircon standard 91500.Different data reduction softwares could yield different uncertainties for calculation of U-Pb ages.The commercially available program GLITTER4.4 could apply an improper uncertainty calculation strategy,but it may yield artificial high precisions for single analyses.Our trace element analyses indicate that Si is not an ideal internal standard for zircon when calibrated against the NIST glasses.Calibration against the NIST glasses using Si as an internal standard,a systematic deviation of 10% 30% was found for most trace elements including Zr.However,the trace element compositions of zircon can be accurately measured by calibration against multiple reference materials with natural compositions (e.g.,BCR-2G,BHVO-2G and BIR-1G),or calibration against NIST SRM 610 and using Zr as an internal standard.Analyses of two pieces of GJ-1 demonstrate that it is relatively homogenous for most trace elements (except for Ti).
基金National Basic Research Program of China,No.2010CB950900No.2014CB954302+1 种基金National Key Technol-ogy R&D Program,No.2013BAC03B00The Key Research Program of the Chinese Academy of Sciences,No.KSZD-EW-Z-021-02
文摘Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change
基金co-supported by the National Natural Science Foundation of China(Grant Nos.40133020 and 40272045)the Chinese Ministry of Science and Technology of China(Grant No.G1999043202)the Chinese Academy of Sciences and the Key Laboratory of Continental Dynamics,Northwest University,the Ministry of Education of China.
文摘Using the in situ zircon U-Pb dating method of LA-ICPMS, we analyzed the 31 Ma old SHRIMP U-Pb age of the Yongsheng nepheline syenite from southern Jilin Province under different spot sizes. The obtained ages are comparable with that of SHRIMP in both accuracy and precision. The age is also identical to that of the Yinmawanshan gabbro from the Liaodong Peninsula within error. Both the Yongsheng nepheline syenite and the Yinmawanshan gabbro represent the youngest known exposed intrusions in northeastern and even eastern China. The results indicate the Eocene mantle-derived magmatic underplating, and the rapid crustal uplifting of this region since 30 Ma. The analyses also document extremely high LREE concentrations and relatively flat REE patterns for the zircons from the Yongsheng nepheline syenite, which represent a new type of zircon REE pattern.
文摘Intelligent manufacturing is a general concept that is under continuous development. It can be categorized into three basic paradigms: digital manufacturing, digital-networked manufacturing, and newgeneration intelligent manufacturing. New-generation intelligent manufacturing represents an indepth integration of new-generation artificial intelligence (AI) technology and advanced manufacturing technology. It runs through every link in the full life-cycle of design, production, product, and service. The concept also relates to the optimization and integration of corresponding systems; the continuous improvement of enterprises' product quality, performance, and service levels; and reduction in resources consumption. New-generation intelligent manufacturing acts as the core driving force of the new indus- trial revolution and will continue to he the main pathway for the transformation and upgrading of the manufacturing industry in the decades to come. Human-cyher-physical systems (HCPSs) reveal the tech- nological mechanisms of new-generation intelligent manufacturing and can effectively guide related the- oretical research and engineering practice. Given the sequential development, cross interaction, and iterative upgrading characteristics of the three basic paradigms of intelligent manufacturing, a technol- ogy roadmap for "parallel promotion and integrated development" should he developed in order to drive forward the intelligent transformation of the manufacturing industry in China.
基金This study was funded by Ministry of Science and Technology of the People’s Republic of China,National Key R&D Programme of China(2017YFC1310901,2016YFC0901002,2017YFC1307905,and 2015BAI12B00)the Youth Programme(QML20180501)+1 种基金National Natural Science Foundation of China(81801152)Beijing Talents Project(2018000021223ZK03 and 2018A13).
文摘China faces the greatest challenge from stroke in the world.The death rate for cerebrovascular diseases in China was 149.49 per 100000,accounting for 1.57 million deaths in 2018.It ranked third among the leading causes of death behind malignant tumours and heart disease.The age-standardised prevalence and incidence of stroke in 2013 were 1114.8 per 100000 population and 246.8 per 100000 person-years,respectively.According to the Global Burden of Disease Study 2017,the years of life lost(YLLs)per 100000 population for stroke increased by 14.6%;YLLs due to stroke rose from third highest among all causes in 1990 to the highest in 2017.The absolute numbers and rates per 100000 population for all-age disability-adjusted life years(DALYs)for stroke increased substantially between 1990 and 2017,and stroke was the leading cause of all-age DALYs in 2017.The main contributors to cerebrovascular diseases include behavioural risk factors(smoking and alcohol use)and pre-existing conditions(hypertension,diabetes mellitus,dyslipidaemia and atrial fibrillation(AF)).The most prevalent risk factors among stroke survivors were hypertension(63.0%-84.2%)and smoking(31.7%-47.6%).The least prevalent was AF(2.7%-7.4%).The prevalences for major risk factors for stroke are high and most have increased over time.Based on the latest national epidemiological data,26.6%of adults aged≥15 years(307.6 million adults)smoked tobacco products.For those aged≥18 years,age-adjusted prevalence of hypertension was 25.2%;adjusted prevalence of hypercholesterolaemia was 5.8%;and the standardised prevalence of diabetes was 10.9%.For those aged≥40 years,the standardised prevalence of AF was 2.31%.Data from the Hospital Quality Monitoring System showed that 3010204 inpatients with stroke were admitted to 1853 tertiary care hospitals during 2018.Of those,2466785(81.9%)were ischaemic strokes(ISs);447609(14.9%)were intracerebral haemorrhages(ICHs);and 95810(3.2%)were subarachnoid haemorrhages(SAHs).The average age of patients admitted was 66 years old,and
基金supported by the National Natural Science Foundation of China (Grant Nos. 90814000,90814002)
文摘The North China Craton (NCC) is a classical example of ancient destroyed cratons.Since the initiation of the North China Craton Destruction Project by the National Natural Science Foundation of China,numerous studies have been conducted on the timing,scale,and mechanism of this destruction through combined interdisciplinary research.Available data suggest that the destruction occurred mainly in the eastern NCC,whereas the western NCC was only locally modified.The sedimentation,magmatic activities and structural deformation after cratonization at ~1.8 Ga indicate that the NCC destruction took place in the Mesozoic with a peak age of ca 125 Ma.A global comparison suggests that most cratons on Earth are not destroyed,although they have commonly experienced lithospheric thinning;destruction is likely to occur only when the craton has been disturbed by oceanic subduction.The destruction of the NCC was coincident with globally active plate tectonics and high mantle temperatures during the Cretaceous.The subducted Pacific slab destabilized mantle convection beneath the eastern NCC,which resulted in cratonic destruction in the eastern NCC.Delamination and/or thermal-mechanical-chemical erosion resulted from the destabilization of mantle convection.
基金supported by the Chinese Academy of Sciences Strategic Priority Research Program(Grant Nos.XDB05020000 and XDA05100100)the National Natural Science Foundation of China(Grant Nos.41230642 and 41021004)
文摘In January 2013, a long-lasting episode of severe haze occurred in central and eastern China, and it attracted attention from all sectors of society. The process and evolution of haze pollution episodes were observed by the "Forming Mechanism and Con- trol Strategies of Haze in China" group using an intensive aerosol and trace gases campaign that simultaneously obtained data at 11 ground-based observing sites in the CARE-China network. The characteristics and formation mechanism of haze pollu- tion episodes were discussed. Five haze pollution episodes were identified in the Beijing-Tianjin-Hebei (Jing-Jin-Ji) area; the two most severe episodes occurred during 9-15 January and 25-31 January. During these two haze pollution episodes, the maximum hourly PMz5 mass concentrations in Beijing were 680 and 530 ~tg m-3, respectively. The process and evolution of haze pollution episodes in other major cities in the Jing-Jin-Ji area, such as Shijiazhuang and Tianjin were almost the same as those observed in Beijing. The external cause of the severe haze episodes was the unusual atmospheric circulation, the depres- sion of strong cold air activities and the very unfavorable dispersion due to geographical and meteorological conditions. How- ever, the internal cause was the quick secondary transformation of primary gaseous pollutants to secondary aerosols, which contributed to the "explosive growth" and "sustained growth" of PM2.5. Particularly, the abnormally high amount of nitric ox- ide (NOx) in the haze episodes, produced by fossil fuel combustion and vehicle emissions, played a direct or indirect role in the quick secondary transformation of coal-burning sulphur dioxide (SO2) to sulphate aerosols. Furthermore, gaseous pollutants were transformed into secondary aerosols through heterogeneous reactions on the surface of fine particles, which can change the particle's size and chemical composition. Consequently, the proportion of secondary inorganic ions, such as sulphate and nitrate, gradually incr
基金the National High Technology R&D Program of China (863 Program),the Major State Basic Research Development Program of China (973 Program),by the National Natural Science Foundation of China,by the Program for New Century Excellent Talents in University of Ministry of Education in China (NCET-09-0401).A patent for this method has been approved by the State Intellectual Property Office of China
文摘Liquid chromatography-mass spectrometry (LC-MS)-based metabolomics has been facilitated by the con- struction of MSz spectral tag (MS2T) library from the total scan ESI MS/MS data, and the development of widely targeted metabolomics method using MS/MS data gathered from authentic standards. In this report, a novel strategy called step- wise multiple ion monitoring-enhanced product ions (stepwise MIM-EPI) was developed to construct the MS2T library, in which stepwise MIM was used as survey scans to trigger the acquisition of EPI. A total number of 698 (almost) non- redundant metabolites with MS2 spectra were obtained, of which 135 metabolites were identified/annotated. Integrating the data gathered from our MS2T library and other available multiple reaction monitoring (MRM) information, a widely targeted metabolomics method was developed to quantify 277 metabolites, including some phytohormones. Evaluation of the dehydration responses and natural variations of these metabolites in rice leaf not only suggested the coordinated regulation of abscisic acid (ABA) with metabolites such as serotonin derivative(s), polyamine conjugates under drought stress, but also revealed some C-glycosylated flavones as the potential markers for the discrimination of indica and japonica rice subspecies. The new MS2T library construction and widely targeted metabolomics strategy could be used as a tool for rice functional genomics.
基金partially supported by the National Key Research and Development Program of China(2016YFA0600103)Delos Living LLCthe Cyrus Tang Foundation
文摘As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations.
基金This work was supported by the National Science and Technology Major Project(2017ZX10103011 and 2017ZX10204401)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2017-I2M-1-009)+1 种基金Shenzhen Science and Technology Research and Development Project(JCYJ20180504165549581 and JCYJ20170413141236903)China Postdoctoral Science Foundation(2019T120147).
文摘The outbreak of the 2019-nCoV infection began in December 2019 in Wuhan,Hubei province,and rapidly spread to many provinces in China as well as other countries.Here we report the epidemiological,clinical,laboratory,and radiological characteristics,as well as potential biomarkers for predicting disease severity in 2019-nCoV-infected patients in Shenzhen,China.All 12 cases of the 2019-nCoV-infected patients developed pneumonia and half of them developed acute respiratory distress syndrome (ARDS).The most common laboratory abnormalities were hypoalbuminemia,lymphopenia,decreased percentage of lymphocytes (LYM) and neutrophils (NEU),elevated C-reactive protein (CRP) and lactate dehydrogenase (LDH),and decreased CD8 count.The viral load of 2019-nCoV detected from patient respiratory tracts was positively linked to lung disease severity.ALB,LYM,LYM (%),LDH,NEU (%),and CRP were highly correlated to the acute lung injury.Age,viral load,lung injury score,and blood biochemistry indexes,albumin (ALB),CRP,LDH,LYM (%),LYM,and NEU (%),may be predictors of disease severity.Moreover,the Angiotensin Ⅱlevel in the plasma sample from 2019-nCoV infected patients was markedly elevated and linearly associated to viral load and lung injury.Our results suggest a number of potential diagnosis biomarkers and angiotensin receptor blocker (ARB) drugs for potential repurposing treatment of 2019-nCoV infection.
文摘There exist differences in the epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selections between gastric cancer patients from the Eastern and Western countries.The Chinese Society of Clinical Oncology(CSCO)has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually.Taking into account regional differences,giving full consideration to the accessibility of diagnosis and treatment resources,these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China.The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis,treatment,follow-up,and screening of gastric cancer.Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines,this updated guideline integrates the results ofmajor clinical studies from China and overseas for the past year,focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations.For the comprehensive treatment of non-metastatic gastric cancer,attentions were paid to neoadjuvant treatment.The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated.For the comprehensive treatment of metastatic gastric cancer,recommendations for immunotherapy were included,and immune checkpoint inhibitors fromthird-line to the first-line of treatment for different patient groups with detailed notes are provided.
基金National Basic Research Program of China, No.2009CB421105National Key Technology R&D Program, No.2006BAC08B00Knowledge Innovation Program of the CAS, No.KSCX1-YW-09-01
文摘Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21 st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period.
基金supported by the National Natural Science Foundation of China (Grant No. 41130313)by the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant No. XDB03010200)
文摘Granite is one of the most important components of the continental crust on our Earth; it thus has been an enduring studied subject in geology. According to present knowledge, granite shows a great deal of heterogeneity in terms of its texture,structure, mineral species and geochemical compositions at different scales from small dike to large batholith. However, the reasons for these variations are not well understood although numerous interpretations have been proposed. The key point of this debate is whether granitic magma can be effectively differentiated through fractional crystallization, and, if so, what kind of crystallization occurred during the magmatic evolution. Although granitic magma has high viscosity because of its elevated SiO2 content, we agree that fractional crystallization is effectively processed during its evolution based on the evidence from field investigation,mineral species and its chemical variations, and geochemical compositions. These data indicate that crystal settling by gravitation is not the only mechanism dominating granitic differentiation. On the contrary, flow segregation or dynamic sorting may be more important. Accordingly, granite can be divided into unfractionated, fractionated(including weakly fractionated and highly fractionated) and cumulated types, according to the differentiation degree. Highly fractionated granitic magmas are generally high in primary temperature or high with various volatiles during the later stage, which make the fractional crystallization much easier than the common granitic melts. In addition, effective magmatic differentiation can be also expected when the magma emplaced along a large scale of extensional structure. Highly fractionated granitic magma is easily contaminated by country rocks due to its relatively prolonged crystallization time. Thus, granites do not always reflect the characteristics of the source areas and the physical and chemical conditions of the primary magma. We proposed that highly fractionated granites are an important sig
文摘China is one of the countries with the highest incidence of gastric cancer.There are differences in epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selection between gastric cancer patients from the Eastern and Western countries.Non-Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer patients.The Chinese Society of Clinical Oncology(CSCO)arranged for a panel of senior experts specializing in all sub-specialties of gastric cancer to compile,discuss,and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence-based medicine in China and abroad.By referring to the opinions of industry experts,taking into account of regional differences,giving full consideration to the accessibility of diagnosis and treatment resources,these experts have conducted experts’consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes.This guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis,comprehensive treatment,and follow-up visits for gastric cancer.
文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).
基金National Natural Science Foundation of China,No.39970831.
文摘AIM: To identify the property of dendritic cells (DCs) of peripheral blood monocytes (PBMC) in patients with chronic HBV infection. METHODS: Twenty patients with persistent HBV infection were included in this study, 10 healthy subjects being used as a control group. The peripheral blood mononuclear cells (PBMC) of T cell-depleted populations were incubated and induced into mature dendritic cells in the RPMI-1640 medium in the presence of cytokines GM-CSF, IL-4, FLt-3,TNF-alpha and 100mL.L(-1 )of fetal calf serum for a total of 10-12 days. The expressions of surface markers on DCs were evaluated using flow cytometric analysis. ELISA method was used to determine the cytokine levels of interleukin-12 (IL-12) and IL-10 in the supernatant produced by DCs. For detection of the stimulatory capacity of DCs to T cell proliferation, mytomycin C-treated DC were incubated with allogenic T cells. RESULTS: A typical morphology of mature DCs from healthy subjects and HBV-infected patients was induced in in vitro incubation, but the proliferation ability and cellular number of DCs from HBV-infected patients significantly decreased compared with healthy individuals. In particular, the expression levels of HLA-DR, CD80 (B7-1) and CD86 (B7-2) on DC surface from patients were also lower than that from healthy individuals (0.46 vs 0.92 for HLA-DR, 0.44 vs 0.88 for CD80 and 0.44 vs 0.84 for CD86,P【0.05). The stimulatory capacity and production of IL-12 of DCs from patients in allogenic mixed lymphocyte reaction (AMLR) significantly decreased, but the production level of nitric oxide (NO) by DCs simultaneously increased compared with healthy subjects (86 +/- 15 vs 170 +/- 22 micromol.L(-1), P 【0.05). CONCLUSION: The patients with chronic HBV infection have the defective function and immature phenotype of dendritic cells, which may be associated with the inability of efficient presentation of HBV antigens to host immune system for the clearance of HBV.
基金supported by the Major StateBasic Research Project (Grant No. G1999053901).
文摘MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.