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1Simultaneous in-situ determination of U-Pb age and trace elements in zircon by LA-ICP-MS in 20 μm spot size显示文摘Simultaneous in-situ determination of U-Pb ages and 20 trace elements of three international zircon standards(91500,GJ1 and TEMORA 1) and one laboratory zircon standard(SK10-2) separated from Cenozoic fine-grained gabbro was carried out on quadrupole ICP-MS equipped with 193 nm excimer laser in 20 μm spot size. The weighted mean 206Pb/238U ages of 91500,GJ1 and TEMORA 1 are 1064.4±4.8 Ma(2σ ),603.2±2.4 Ma(2σ ) and 418.2±2.4 Ma(2σ ),respectively. The relative standard de-viations(RSDs) of 206Pb/238U ages(2σ ) are less than 2.2% for single measurements and 0.6% for weighted means. The obtained weighted mean 206Pb/238U ages of three standard zircons agree with the recommended values within 2σ error. The weighted mean 206Pb/238U age of SK10-2 is 31.42±0.25 Ma(2σ ) and the RSDs of 206Pb/238U ages(2σ ) are between 2.4% and 5.7% for single measurements and less than 0.8% for weighted mean. The obtained weighted mean 206Pb/238U age is in good agreement with the age obtained by Yuan(2004). Trace element concentrations of NIST612 and NIST614 obtained under the same LA-ICP-MS operating conditions agree with the recommended values within analytical error. The results indicate that it is possible to measure U-Pb age and trace elements simultaneously by LA-ICP-MS in a small spot size of 20 μm.LIU XiaoMing GAO Shan DIWU ChunRong YUAN HongLin HU ZhaoChu 2007Chinese Science Bulletin2007,52,9:107
2Nano-Graphene Oxide for Cellular Imaging and Drug Delivery显示文摘Two-dimensional graphene offers interesting electronic,thermal,and mechanical properties that are currently being explored for advanced electronics,membranes,and composites.Here we synthesize and explore the biological applications of nano-graphene oxide(NGO),i.e.,single-layer graphene oxide sheets down to a few nanometers in lateral width.We develop functionalization chemistry in order to impart solubility and compatibility of NGO in biological environments.We obtain size separated pegylated NGO sheets that are soluble in buffers and serum without agglomeration.The NGO sheets are found to be photoluminescent in the visible and infrared regions.The intrinsic photoluminescence(PL)of NGO is used for live cell imaging in the near-infrared(NIR)with little background.We found that simple physisorption viaπ-stacking can be used for loading doxorubicin,a widely used cancer drug onto NGO functionalized with antibody for selective killing of cancer cells in vitro.Owing to its small size,intrinsic optical properties,large specifi c surface area,low cost,and useful non-covalent interactions with aromatic drug molecules,NGO is a promising new material for biological and medical applications.Xiaoming Sun Zhuang Liu Kevin Welsher Joshua Tucker Robinson Andrew Goodwin Sasa Zaric Hongjie Dai 2008Nano Research2008,1,3:118
3Determination of U-Pb age and rare earth element concentrations of zircons from Cenozoic intrusions in northeastern China by laser ablation ICP-MS显示文摘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.YUAN Honglin WU Fuyuan GAO Shan LIU Xiaoming XU Ping SUN Deyou 2003Chinese Science Bulletin2003,48,22:252
4Hf isotopes of the 3.8 Ga zircons in eastern Hebei Province, China: Implications for early crustal evolution of the North China Craton显示文摘Zircon U-Pb dating indicates that the fuchsite quartzite in eastern Hebei Province was derived from weathering and erosion of the 3.6-3.8 Ga granitic rocks. In-situ zircon Hf analyses show that the Lu-Hf isotopic system remained closed during later thermal disturbances. Zircons with concordant ages have Hf isotopic model ages of about 3.8 Ga, suggesting a recycling of this ancient crust. The ~3.8 Ga zircons have similar Hf isotopic compositions to those of chondrite, indicating that their source rocks (granitic rocks) were derived from partial melting of the juvenile crust which originated from a mantle without significant crust-mantle differentiation. Therefore, it is proposed that there was no large-scale crustal growth before ~3.8 Ga in eastern Hebei Province. Considering zircon Hf isotopic data from other areas, it is concluded that the most ancient crust in the North China Craton probably formed at about 4.0 Ga, and the possibility to find crust older than 4.0 Ga is very limited.WU Fuyuan YANG Jinhui LIU Xiaoming LI Tiesheng XIE Liewen YANG Yueheng 2005Chinese Science Bulletin2005,50,21:51
5Mesozoic Bimodal Volcanic Suite in Zhalantun of the Da Hinggan Range and Its Geological Significance: Zircon U-Pb Age and Hf Isotopic Constraints显示文摘Mesozoic bimodal volcanic rocks of basaltic andesite and rhyolite are widely distributed in the Da Hinggan Range, but their petrogenetic relationships and geodynamic implications are rarely constrained. Detailed studies on doleritic and porphyry dikes in the Zhalantun area indicate that they display features of magma mixing, suggesting their coeval formation. In situ zircon U-Pb dating shows that the porphyry was emplaced in the Early Cretaceous with a 206Pb/238U age of 130±1 Ma. Zircons from the dolerite also yield an Early Cretaceous emplacement age of 124±2 Ma although some inherited zircons have been identified. These age results indicate that the Early Cretaceous was an important period of magmatism in the Da Hinggan Range. Zircons from porphyry are characterized by positive value of εHf(t) as high as 10.3±0.5 with Hf depleted mantle model age of 349–568 Ma, whereas magmatic zircons from the dolerite have εHf(t) value of 11.0±1.4 with Hf depleted mantel model age of 342–657 Ma, consistent with those from the porphyry. Considering other data on the geological evolution of this area, it is concluded that the mafic magma originated from the partial melting of Paleozoic enriched lithospheric mantle, whereas the felsic magma came from recycling of juvenile crust formed during the Paleozoic. Both of the protoliths are closely related to the subduction of the Paleo-Asian Ocean during the Paleozoic, indicating that the Paleozoic is an important period of large-scale crustal growth in the area.ZHANG Jiheng GE Wenchun WU Fuyuan LIU Xiaoming 2006Acta Geologica Sinica(English Edition)2006,80,1:52
6Zircon U-Pb geochronology of basement metamorphic rocks in the Songliao Basin显示文摘Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphic rocks in the Songliao Basin mainly consist of metagabbro (L45-1), amphibolite (SN117), metarhyolitical tuff (G190), sericite (Ser) schist (N103), chlorite (Chl) schist (T5-1), biotite (Bi)-actinolite (Act)-quartz (Q) schist (Y205), and metagranite (L44-1). The cathodoluminesence (CL) images of the zircons from metagabbro (L45-1) and metagranite (L44-1) indicate that they have cores of magmatic origin and rims of metamorphic overgrowths. Their U-Pb isotopic ages are 1808±21 Ma and 1873±13 Ma, respectively. The zircons with oscillatory zoning from amphibolite (SN117) and Chl schist (T5-1), being similar to those of mafic igneous rocks, yield ages of 274 ± 3.4 Ma and 264 ± 3.2 Ma, re-spectively. The zircons from metarhyolitical tuff (G190) and Ser schist (N103) display typical magmatic growth zoning and yield ages of 424 ± 4.5 Ma and 287 ± 5.1Ma, respectively. Most of zircons from Bi-Act-Q schist (Y205) are round in shape and different in absorption degree in the CL images, implying their sedimentary detritals. U-Pb dating yield concordant ages of 427 ± 3.1Ma, 455 ± 12 Ma, 696 ± 13 Ma, 1384±62 Ma, 1649±36 Ma, 1778±18 Ma, 2450±9 Ma, 2579±10 Ma, 2793±4 Ma and 2953±14 Ma. The above-mentioned results indicate that the Precambrian crystalline basement (1808―1873 Ma) exists in the southern Songliao Basin and could be related to tectonic thrust, and that the Early Paleozoic (424―490 Ma) and Late Paleozoic magmatisms (264―292 Ma) also occur in the basin basement, which are consistent with the ages of the detrital zircons from Bi-Act-Q schist in the basement.PEI FuPing XU WenLiang YANG DeBin ZHAO QuanGuo LIU XiaoMing HU ZhaoChu 2007Chinese Science Bulletin2007,52,7:57
7U–Pb ages and Hf isotopes for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southwestern margin of the North China Craton显示文摘In situ U-Pb dating and Lu-Hf isotopic analysis were carried out for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southern margin of the North China Craton (NCC). The re- sults provide further constraints on the crustal formation and evolution history of NCC. Four 207Pb/206Pb age populations were obtained from 99 analyses, with clusters at ~3.40 Ga, 2.77―2.80 Ga, ~2.50 Ga and 2.34 Ga, respectively. The 3.40 Ga old zircons have similar Hf isotopic compositions to those from Ar- chean rocks in the Jidong and Anshan areas of NCC. However, crustal remnants older than 3.6 Ga have been identified in the southern margin of NCC, the South China Craton, the northwestern part of the Qinling Orogen and its adjacent area. Thus, it is not easy to trace the source rock from which the 3.40 Ga detrital zircons were derived. It can be inferred that the crustal remnants older than 3.40 Ga might have been widely distributed in the North China Craton. The 2.77―2.80 Ga zircons make up a relatively small proportion and have the highest εHf (t) values (up to 6.1±1.6), consistent with the Hf isotopic composition of the depleted mantle at 2.83 Ga. Their single-stage Hf model age of 2.83 Ga is close to their crystallized age, suggesting that their source rocks were extracted from the contemporaneous depleted mantle. The ~2.50 Ga zircon grains constitute about 85% of the total grain population and their Hf isotopic compositions indicate major growth of juvenile crust at ~2.50 Ga but minor reworking of ancient crust. The youngest zircon dated in this study gave an U-Pb age of 2337±23 Ma, which can be considered the maximum depositional age of the formation of the Songshan Group.DIWU ChunRong SUN Yong YUAN HongLin WANG HongLiang ZHONG XingPing LIU XiaoMing 2008Chinese Science Bulletin2008,53,18:54
8Research advances in magnesium and magnesium alloys worldwide in 2020显示文摘Research on magnesium alloys continues to attract great attention,with more than 3000 papers on magnesium and magnesium alloys published and indexed in SCI in 2020 alone.The results of bibliometric analyses show that microstructure control and mechanical properties of Mg alloys are continuously the main research focus,and the corrosion and protection of Mg alloys are still widely concerned.The emerging research hot spots are mainly on functional magnesium materials,such as Mg ion batteries,hydrogen storage Mg materials,and bio-magnesium alloys.Great contributions to the research and development of magnesium alloys in 2020 have been made by Chongqing University,Chinese Academy of Sciences,Central South University,Shanghai Jiaotong University,Northeastern University,Helmholtz Zentrum Geesthacht,etc.The directions for future research are suggested,including:1)the synergistic control of microstructures to achieve high-performance magnesium alloys with concurrent high strength and superior plasticity along with high corrosion resistance and low cost;2)further development of functional magnesium materials such as Mg batteries,hydrogen storage Mg materials,structural-functional materials and bio-magnesium materials;3)studies on the effective corrosion protection and control of degradation rate of magnesium alloys;4)further improvement of advanced processing technology on Mg alloys.Yan Yang Xiaoming Xiong Jing Chen Xiaodong Peng Daolun Chen Fusheng Pan 2021Journal of Magnesium and Alloys2021,9,3:52
9Timing of the Wudangshan, Yaolinghe volcanic sequences and mafic sills in South Qinling: U-Pb zircon geochronology and tectonic implication显示文摘The Wudangshan, Yaolinghe volcanic-sedimentary sequences and doleritic-gabbroic sills comprise the largest exposed Precambrian basement in South Qinling. Zircons separated from 5 volcanic-pyroclas- tic samples of the Wudangshan Group, 2 volcanic samples of the Yaolinghe Group and one sample for the mafic sills were used for U-Pb dating by laser ablation-inductively coupled plasma mass spec- trometry (LA-ICPMS). The results reveal that the Wudangshan volcanic sequence was formed at (755±3) Ma (a weighted mean from the 5 samples, MSWD=0.47), whereas the Yaolinghe volcanic suite and the mafic sill were crystallized at (685±5) (2 samples, MSWD=0.36) and (679±3) Ma (MSWD=1.6), respectively, which are equal to each other within analysis errors. These ages are markedly younger than those previously documented for the rocks. The newly obtained ages for the Wudangshan and Yaolinghe Groups are identical to those of the bottom Liantuo and slightly older than those of the Nantuo Forma- tions, respectively, lower strata of the Nanhua (middle to late Neoproterozoic) stratotype section in eastern Three Gorges, Yangtze craton. A range of inherited magmatic zircons was recognized with ages of 830 to 780 Ma, which are typical of Neoprotzrozoic magmatisms recorded along the margins and interior of the Yangtze craton. Thus, there is Neoproterozoic basement comprising 830―780 Ma igne- ous suites in South Qinling; the inherited zircons were detrital sediments derived from the northern margin of the Yangtze craton. Accordingly, it is suggested that the South Qinling is a segment of the Yangtze craton before the Qinling Orogeny.LING WenLi REN BangFang DUAN RuiChun LIU XiaoMing MAO XinWu PENG LianHong LIU ZaoXue CHENG JianPing YANG HongMei 2008Chinese Science Bulletin2008,53,14:44
10Influence of tectonic stress on coalification:Stress degradation mechanism and stress polycondensation mechanism显示文摘The function of pressure for coalification is a long-term controversial issue, and the main cause is that the strata pressure and the tectonic stress were confused, which are two different actions of 'pres-sure' . The former benefits the physical coalification but retards the chemical coalification, whereas the latter may not only affect the physical structure of coal but also promote its chemical composition changes. In accordance with the organic molecule evolution of coal, there are two kinds of basic mechanisms of the influence of the tectonic stress on the chemical coalification: the tectonic stress degradation and the tectonic stress polycondensation. The stress degradation mechanism is a process of that, when the tectonic stress acted on the large molecule of coal in the form of mechanical force or kinetic energy, some chemical bonds of low decomposed energy, such as aliphatic side-chain and oxygenic functional groups, were broken up and then were degraded into free radicals of less mo-lecular weight, and finally escaped from coal in the form of liquid organic matter (hydrocarbon). The stress polycondensation is considered that, under the control of the anisotropic tectonic stress, the condensed aromatic nucleus trend to be parallel arranged and to be enhanced through rotating or displacing of aromatic rings, the basic structural unit of coal (BSU) increases by directional develop-ment and preferential stack. X-ray diffraction (XRD), Fourier transformation infrared microspectroscopy (FTIR), and rock pyrolysis analysis (Rock-eval) were employed to study the deformed coal series and the non-deformed coal series. The results showed that, compared with the non-deformed coal, the de-formed coal exhibits particular characteristics: weaker aliphatic absorbance peak and stronger aro-matic absorbance peak, lower pyrolysed hydrocarbon yield, and more increscent BSU. The concepts of stress degradation mechanism and stress polycondensation mechanism presented here would not deny the dominant function of the temperature in coalification, but emphasize the 'catalysis' of the tectonic stress in coalification.CAO DaiYong LI XiaoMing ZHANG ShouRen 2007Science China Earth Sciences2007,50,1:36
11Thinopyrum ponticum and Th. intermedium: the promising source of resistance to fungal and viral diseases of wheat显示文摘Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat (Ttricum aestivum). Because of their readily crossing with wheat, many genes for disease resistance have been introduced from the wheatgrasses into wheat. Genes for resistance to leaf rust, stem rust, powdery mildew, Barley yellow dwarf virus, Wheat streak mosaic virus, and its vector, the wheat curl mite, have been transferred into wheat by producing chromosome translocations. These genes offer an opportunity to improve resistance of wheat to the diseases; some of them have been extensively used in protecting wheat from damage of the diseases. Moreover, new resistance to diseases is continuously detected in the progenies of wheat-Thinopyrum derivatives. The present article summaries characteri-zation and application of the genes for fungal and viral diseaseresistance derived from Th. ponticum and Th. intermedium.Hongjie Li Xiaoming Wang 2009Journal of Genetics and Genomics2009,36,9:35
12A unified theory for elastic wave propagation through porous media containing cracks-An extension of Biot's poroelastic wave theory显示文摘Rocks in earth’s crust usually contain both pores and cracks. This phenomenon significantly affects the propagation of elastic waves in earth. This study describes a unified elastic wave theory for porous rock media containing cracks. The new theory extends the classic Biot’s poroelastic wave theory to include the effects of cracks. The effect of cracks on rock’s elastic prop erty is introduced using a crack-dependent dry bulk modulus. Another important frequency-dependent effect is the 'squirt flow' phenomenon in the cracked porous rock. The analytical results of the new theory demonstrate not only reduction of elas tic moduli due to cracks but also significant elastic wave attenuation and dispersion due to squirt flow. The theory shows that the effects of cracks are controlled by two most important parameters of a cracked solid: crack density and aspect ratio. An appealing feature of the new theory is its maintenance of the main characteristics of Biot’s theory, predicting the characteristics of Biot’s slow wave and the effects of permeability on elastic wave propagation. As an application example, the theory cor rectly simulates the change of elastic wave velocity with gas saturation in a field data set. Compared to Biot theory, the new theory has a broader application scope in the measurement of rock properties of earth’s shallow crust using seismic/acoustic waves.TANG XiaoMing 2011Science China Earth Sciences2011,54,9:37
13U-Pb zircon dating constraints on formation time of Qilian high-grade metamorphic rock and its tectonic implications显示文摘In order to constrain the formation time of high-grade metamorphic rocks in the Qilian Mountains, U-Pb zircon dating was carried out by using LA-ICPMS technique for a paragneiss of the Hualong Group in the Qilian Mountains basement series and a weakly foliated granite that intruds into the Hualong Group. Zircons from the paragneiss consist dominantly of detrital magma zircons with round or sub-round shape. They have 207Pb/206Pb ages mostly ranging from 880 to 900 Ma, with a weighted mean age of 891 ±9 Ma, which is interpreted as the magma crystallization age of its igneous provenance and can be taken as a lower age limit for the Hualong Group. Magma crystallization age for the weak-foliated granite is 875±8 Ma, which can be taken as an upper age limit for the Hualong Group. Accordingly, the formation time of the Hualong Group is constrained at sometime between 875 and 891 Ma. A few zir- cons from both paragneiss and weak-foliated granite display old inherited ages of 1000 to 1700 Ma and young metamorphic ages of Early Paleozoic. The zircon age distribution pattern confirms that the Qilian Mountains and the northern margin of Qaidam Basin had a united basement, with geotectonic affinity to the Yangtze Block. The results also reveal that sediments of the Hualong Group formed by rapid accumulation due to rapid crustal uplift-erosion. This process may result from intensive Neoproterozoic orogenesis due to assembly of the suppercontinent Rodinia.XU WangChun ZHANG HongFei LIU XiaoMing 2007Chinese Science Bulletin2007,52,4:32
14LA-ICP-MS zircon U-Pb dating from granitoids in southern basement of Songliao basin:Constraints on ages of the basin basement显示文摘Seven LA-ICP-MS zircon U-Pb datings from granitoids in the southern basement of the Songliao basin were done in order to constrain the ages of the basin basement. The cathodoluminescence (CL) images of the zircons from seven granitoids indicate that they are euhedral-subhedral ones with striped ab-sorption and obvious oscillatory zoning rims. The dating results show that a weighted mean 206Pb/238U age is 236±3 Ma for quartz diorite (sample No.T6-1) located in the western slope of the basin,that weighted mean 206Pb/238U ages are 319±1 Ma (2126 m) and 361±2 Ma (1994 m) for diorite (sample No.YC1-1) and granite (sample No.YC1-2) located in northern part of southeastern uplift of the basin,respectively,and that weighted mean 206Pb/238U ages are 161±5 Ma,165±2 Ma,165±1 Ma and 161±4 Ma for samples Q2-1,SN121,SN122,and SN72 granitoids located in southern part of southeastern uplift of the basin,respectively. The statistical results of ages suggest that the middle Jurassic granitoids con-stitute the main part of basement granitoids,and that the Hercynian and Indo-Sino magmatisms also occur in the basin basement. It is implied that the Songliao basin should be a rift one formed in the intracontinent or active continental margin settings in the late Mesozoic after the Middle Jurassic orogeny took place.GAO FuHong XU WenLiang YANG DeBin PEI FuPing LIU XiaoMing HU ZhaoChu 2007Science China Earth Sciences2007,50,7:31
15父母和同伴因素对青少年饮酒行为的影响显示文摘环境是影响青少年饮酒行为的重要因素之一。本研究以南京市初一、初二、高一、高二共995个中学生为被试,考察父母和同伴因素对青少年饮酒行为的影响以及相对影响力。要求青少年自我报告他们自己、父母和同伴的饮酒行为和态度以及父母监控、父母教养方式情况。结果表明:(1)青少年的饮酒行为较为普遍,70%左右的青少年曾饮过啤酒或葡萄酒,25%左右的青少年曾饮过白酒。约10%的青少年经常饮啤酒和葡萄酒,2%的青少年经常饮白酒;(2)父/母饮酒行为和态度、父母监控、父母教养方式、同伴饮酒人数和态度与青少年的饮酒行为显著相关;(3)Amos结果表明,父母饮酒行为和态度对青少年饮酒行为有直接的预测作用,父母饮酒行为和态度还通过同伴饮酒人数和态度间接地预测青少年的饮酒行为。同时,父母饮酒行为和态度对青少年饮酒行为的影响力大于同伴饮酒行为和态度的影响力。林丹华 Xiaoming Li 方晓义 冒荣 2008心理发展与教育2008,24,3:29
16Basic Topology and Key Devices of the Five-Terminal DC Grid显示文摘Due to their high controllability and flexibility,DC power grids have broad application prospects in the fields of networking of renewable energy and the power supply for oceanic archipelagos and future cities.This paper describes the system topology,control strategy,DC breaker configuration,and research,development and testing of converter valves and DC breaker equipment of the Zhoushan multi-terminal DC transmission system.Zhejiang Zhoushan has unique geographical and developmental features to demonstrate the irreplaceable technical advantages of a DC power grid for providing reliable power supply.The experience gained from the Zhoushan DC power grid project can offer valuable insights into the development and utilization of this technology worldwide.Guangfu Tang Zhiyuan He Hui Pang Xiaoming Huang Xiao-Ping Zhang 2015CSEE Journal of Power and Energy Systems2015,1,2:30
17Effect of inorganic carbon on anaerobic ammonium oxidation enriched in sequencing batch reactor显示文摘The present lab-scale research reveals the enrichment of anaerobic ammonium oxidation microorganism from methanogenic anaerobic granular sludge and the effect of inorganic carbon(sodium bicarbonate)on anaerobic ammonium oxidation.The enrichment of anammox bacteria was carried out in a 7.0-L sequencing batch reactor(SBR)and the effect of bicarbonate on anammox was conducted in a 3.0-L SBR.Research results,especially the biomass,showed first signs of anammox activity after 54 d cultivation with synthetic w...LIAO, Dexiang LI, Xiaoming YANG, Qi ZENG, Guangming GUO, Liang YUE, Xiu 2008Journal of Environmental Sciences2008,20,8:28
18Manganese is critical for antitumor immune responses via cGAS-STING and improves the efficacy of clinical immunotherapy显示文摘CD8^+T cell-mediated cancer clearance is often suppressed by the interaction between inhibitory molecules like PD-1 and PD-L1,an interaction acts like brakes to prevent T cell overreaction under normal conditions but is exploited by tumor cells to escape the immune surveillance.Immune checkpoint inhibitors have revolutionized cancer therapeutics by removing such brakes.Unfortunately,only a minority of cancer patients respond to immunotherapies presumably due to inadequate immunity.Antitumor immunity depends on the activation of the cGAS-STING pathway,as STING-deficient mice fail to stimulate tumor-infiltrating dendritic cells(DCs)to activate CD8^+T cells.STING agonists also enhance natural killer(NK)cells to mediate the clearance of CD8^+T cell-resistant tumors.Therefore STING agonists have been intensively sought after.We previously discovered that manganese(Mn)is indispensable for the host defense against cytosolic dsDNA by activating cGAS-STING.Here we report that Mn is also essential in innate immune sensing of tumors and enhances adaptive immune responses against tumors.Mn-insufficient mice had significantly enhanced tumor growth and metastasis,with greatly reduced tumor-infiltrating CD8^+T cells.Mechanically,Mn^2+promoted DC and macrophage maturation and tumor-specific antigen presentation,augmented CD8^+T cell differentiation,activation and NK cell activation,and increased memory CD8^+T cells.Combining Mn^2+with immune checkpoint inhibition synergistically boosted antitumor efficacies and reduced the anti-PD-1 antibody dosage required in mice.Importantly,a completed phase 1 clinical trial with the combined regimen of Mn^2+and anti-PD-1 antibody showed promising efficacy,exhibiting type I IFN induction,manageable safety and revived responses to immunotherapy in most patients with advanced metastatic solid tumors.We propose that this combination strategy warrants further clinical translation.Mengze Lv Meixia Chen Rui Zhang Wen Zhang Chenguang Wang Yan Zhang Xiaoming Wei Yukun Guan Jiejie Liu Kaichao Feng Miao Jing Xurui Wang Yun-Cai Liu Qian Mei Weidong Han Zhengfan Jiang 2020Cell Research2020,30,11:27
19Discrimination of the rare medicinal plant Dendrobium officinale based on naringenin, bibenzyl, and polysaccharides显示文摘The aim of this study was to establish a method for discriminating Dendrobium officinale from four of its close relatives Dendrobium chrysanthum, Dendrobium crystallinum, Dendrobium aphyllum and Dendrobium devonianum based on chemical composition analysis. We analyzed 62 samples of 24 Dendrobium species. High performance liquid chromatography analysis confirmed that the four low molecular weight compounds 4′,5,7-trihydroxyflavanone (naringenin), 3,4-dihydroxy-4′,5-dime- thoxybibenzyl (DDB-2), 3′,4-dihydroxy-3,5′-dimethoxybibenzyl (gigantol), and 4,4′-dihydroxy-3,3′,5-trimethoxybibenzyl (moscatilin), were common in the genus. The phenol-sulfuric acid method was used to quantify polysaccharides, and the monosaccharide composition of the polysaccharides was determined by gas chromatography. Stepwise discriminant analysis was used to differentiate among the five closely related species based on the chemical composition analysis. This proved to be a simple and accurate approach for discriminating among these species. The results also showed that the polysaccharide content, the amounts of the four low molecular weight compounds, and the mannose to glucose ratio, were important factors for species discriminant. Therefore, we propose that a chemical analysis based on quantification of naringenin, bibenzyl, and polysaccharides is effective for identifying D. officinale.CHEN XiaoMe WANG FangFei WANG YunQiang LI XueLan WANG AiRong WANG ChunLan GUO ShunXing 2012Science China(Life Sciences)2012,55,12:25
20Petrogenesis of Mesozoic High-Mg Diorites in Western Shandong: Evidence from Chronology and Petro-geochemistry显示文摘The high-Mg diorites, widely occurring in western Shandong, have important implications in the study of the relationship between the Mesozoic magmatism and the nature of the lithosphere and its thinning period in the eastern North China craton (NCC). The Tietonggou and Jinling intrusions are typically representatives. LA-ICP-MS zircon U-Pb dating, major and trace element and Sr-Nd isotopic compositions of the Mesozoic intrusive rocks from western Shandong, eastern China, were analyzed. The weighted mean 206Pb/ 238U ages from LA-ICP-MS zircon U-Pb dating results for early norite-diorite, late pyroxene-diorite from the Tietonggou intrusion and biotite-diorite from the Jinling intrusion are (131.4±4.9) Ma(n=15), (134.5±2.3) Ma(n=13), and (132.8±4.2) Ma(n=12), respectively, implying that they were formed in the Early Cretaceous. The weighted mean 207Pb/ 206Pb ages for round zircons from late pyroxene-diorite in the Tietonggou intrusion is (2 513±54) Ma(n=8), suggesting that the basement of the North China craton should exist in the research area. The high-Mg diorites are characterized by enrichment in MgO, Na2O, and light rare earth elements (LREE), and they are poor in heavy rare earth elements (HREE) and high field strength elements (HFSE), being similar to adakite. The existence of the mantle peridotite xenoliths with a high-Mg feature for these intrusive rocks implies that their primary magma should be derived from the upper mantle. However, Sr-Nd isotopic compositions (I sr: 0.704 75-0.707 15; ε Nd(130 Ma) values: -3.95 to -13.30), depletion in HFSE, and the occurrence of Archean inherited zircons suggest that crustal materials could be involved in the derivation of the primary magma. The compositional difference between the diorites from the Tietonggou and Jinling intrusions could be attributed to those of magma sources and degrees of partial melting. The Early Cretaceous high-Mg diorites are considered to have been formed by the mixed melting of the delaminated lithosphere (lithospheric mantle + crust) and asthenosphere, based on their geochemistry, the mantle-derived xenoliths, and the Early Mesozoic lithospheric evolutionary history of the eastern North China craton.Yang Chenghai Xu Wenliang Yang Debin Liu Changchun Liu Xiaoming Hu Zhaochu 2005Journal of China University of Geosciences2005,16,4:24
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