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1Carboniferous Post-collisional Rift Volcanism of the Tianshan Mountains, Northwestern China显示文摘The Tianshan Carboniferous post-collisional rift volcanic rocks occur in northwestern China as a large igneous province. Based on petrogeochemical data, the Tianshan Carboniferous post-collisional rift basic lavas can be classified into two major magma types: (1) the low-Ti/Y type situated in the eastern-central Tianshan area, which exhibits low Ti/Y (<500), Ce/Yb (<15) and SiO2 (43-55%), and relatively high Fe2O3T (6.4-11.5%); (2) the high-Ti/Y type situated in the western Tianshan area, which has high Ti/Y (>500), Ce/Yb (>11) and SiO2 (49-55%), and relatively low Fe2O3T (5.8-7.8%). Elemental data suggest that chemical variations of the low-Ti/Y and high-Ti/Y lavas cannot be explained by fractional crystallization from a common parental magma. The Tianshan Carboniferous basic lavas originated most likely from an OIB-like asthenospheric mantle source (87Sr/86Sr(t) ≈ 0.703-0.705, εNd(t) ≈ +4 to +7). The crustal contamination and continental lithospheric mantle have also contributed significantly to the formation of the basic lavas of the Tianshan Carboniferous post-collisional rift. The silicic lavas were probably generated by partial melting of the crust. The data of this study show that spatial petrogeochemical variations exist in the Carboniferous post-collisional rift volcanics province in the Tianshan region. Occurrence of the thickest volcanics dominated by tholeiitic lavas may imply that the center of the mantle-melting anomaly (mantle plume) was in the eastern Tianshan area at that time. The basic volcanic magmas in the eastern Tianshan area were generated by a relatively high degree of partial melting of the mantle source around the spinel-garnet transition zone, whereas the alkaline basaltic lavas are of the dominant magma type in the western Tianshan area, which were generated by a low degree of partial melting of the mantle source within the stable garnet region, thus the basic lavas of the western Tianshan area might have resulted from relatively thick lithosphere and low geothermal gradient.XIA Linqi, XU Xueyi, XIA Zuchun, LI Xiangmin, MA Zhongping and WANG Lishe Xi’an Institute of Geology and Mineral Resources, China Geological Survey, Xi’an, Shaanxi 710054 E-mail: geologyx@pub.xaonline.com. Liu Shuchun and Liu Xinzhu 2003Acta Geologica Sinica(English Edition)2003,77,3:49
2Reassessment of petrogenesis of Carboniferous—Early Permian rift-related volcanic rocks in the Chinese Tianshan and its neighboring areas显示文摘The Carboniferous Early Permian rill-related volcanic successions.covering large areas in the Chinese Tianshan and its adjacent areas.make up a newly recognized important Phanerozoic large igneous province in the world.which can be further divided into two sub-provinces:Tianshan and Tarim. The regional unconformity of Lower Carboniferous upon basement or pre-Carboniferous rocks.the ages (360—351 Ma) of the youngest ophiolite and the peak of subduction metamorphism of high pressure-low temperature metamorphic belt and the occurrence of Ni-Cu-bearing mafic-ultramatic intrusion with age of—352 Ma and A-type granite with age of~358 Ma reveal that the final closure of the Paleo Asian Ocean might lake place in the Early Mississippian.Our summation shows that at least four criteria.being normally used to identify ancient asthenosphere upwelling(or mantle plumes),are met for this large igneous province:(1) surface uplift prior to magmatism:(2) being associated with continental ifting and breakup events:(3) chemical characteristics of asthenosphere(or plume) derived basalts;(4) close links to large-scale minerali/alion and the uncontaminaled basalts,being analogous to those of many 'ore-bearing' large igneous provinces.display Sr-Nd isotopic variations between plume and EMI geochemical signatures.These suggest that a Carboniferous asthenosphere upwelling and an Early Permian plume played the central role in the generation of the Tianshan—Tarim(central Asia) large igneous province.Linqi Xia Xueyi Xu Xiangmin Li Zhongping Ma Zuchun Xia 2012Geoscience Frontiers2012,3,4:30
3~4.1 Ga xenocrystal zircon from Ordovician volcanic rocks in western part of North Qinling Orogenic Belt显示文摘High-precision U-Pb dating by in situ LA-ICP-MS yields an age of 4079±5 Ma for a xenocrystal zircon from Ordovician volcanics of the Caotangou Group in western part of the North Qinling Orogenic Belt. As a result, the North Qinling Orogenic Belt becomes one of a few localities in the world that contain Hadean age records (4276±6 Ma and 4404±8 Ma detrital zircons from Jack Hill of the Yilgarn craton, 4016 Ma Acasta gneisses of the Wopmay Orogeny and Burang quartzite with detrital zircon of 4103 Ma in Tibet). It is also the first report of the Hadean age in Phanerozoic volcanics. The finding of the 4.1 Ga xenocrystal zircon provides not only the geochronological record of the oldest crustal materials in China, but also the condition for further search for rocks forming in the region during the early time of the Earth’s evolution. Thirty-six zircon U-Pb dates from the Ordovician volcanic rocks are subgrouped into seven generations that represent different tectono-magmatic events in the North Qinling Orogenic Belt. Among them, two periods of 0.9-1.5 Ga and 0.4-0.5 Ga are consistent with Mesoproterozoic and Early Paleozoic orogenies, respectively.WANG HongLiang CHEN Liang SUN Yong LIU XiaoMing xu XueYi CHEN JuanLu ZHANG Hong DIWU ChunRong 2007Chinese Science Bulletin2007,52,21:23
4Current status of diagnosis and treatment of bladder cancer in China-Analyses of Chinese Bladder Cancer Consortium database显示文摘Objective:To investigate current status of diagnosis and treatment of bladder cancer in China.Methods:A database was generated by Chinese Bladder Cancer Consortium(CBCC).From January 2007 to December 2012,14,260 cases from 44 CBCC centers were included.Data of diagnosis,treatment and pathology were collected.Results:The average age was 63.5 year-old and most patients were male(84.3%).The most common histologic types were urothelial carcinoma(91.4%),adenocarcinoma(1.8%),and squamous carcinoma(1.9%).According to 1973 and 2004 WHO grading system,42.0%,41.0%,and 17.0% of patients were grade 1,2,and 3,and 16.0%,48.7%,and 35.3% of patients were papillary urothelial neoplasms of low malignant potential,low,and high grade,respectively.Non-muscle invasive bladder cancer(NMIBC)and muscle invasive bladder cancer(MIBC)were 25.2% and 74.1%,respectively(0.8% not clear).Carcinoma in situ was only 2.4%.Most patients were diagnosed by white-light cystoscopy with biopsy(74.3%).Fluorescence and narrow band imaging cystoscopy had additional detection rate of 1.0% and 4.0%,respectively.Diagnostic transurethral resection(TUR)provided detection rate of 16.9%.Most NMIBCs were treated with TUR(89.2%).After initial TUR,2.6%accepted second TUR,and 45.7%,69.9%,and 58.7% accepted immediate,induced,and maintenance chemotherapy instillation,respectively.Most MIBCs were treated with radical cystectomy(RC,59.7%).Laparoscopic RCs were 35.1%,while open RC 63.4%.Extended and standard pelvic lymph node dissection were 7% and 66%,respectively.Three most common urinary diversions were orthotopic neobladder(44%),ileal conduit(31%),and ureterocutaneostomy(23%).Only 2.3% of patients accepted neo-adjuvant chemotherapy and only 18%of T3 and T4 patients accepted adjuvant chemotherapy.Conclusion:Disease characteristics are similar to international reports,while differences of diagnosis and treatment exist.This study can provide evidences for revisions of the guideline on bladder cancer in China.Kaiwen Li Tianxin Lin Wei Xue Xin Mu Enci Xu Xu Yang Fubao Chen Guangyong Li Lulin Ma Guoliang Wang Chaozhao Liang Haoqiang Shi Ming Li Mao Tang Xueyi Xue Yisong Lv Yaoliang Deng Chengyang Li Zhiwen Chen Xiaozhou Zhou Fengshuo Jin Xudong Liu Jinxin Wei Lei Shi Xin Gou Weiyang He Liqun Zhou Lin Cai Baiye Jin Guanghou Fu Xiangbo Kong Hongyan Sun Ye Tian Lang Feng Tiejun Pan Yiyi Wu Dongwen Wang Hailong Hao Benkang Shi Yaofeng Zhu Qiang Wei Ping Han Changli Wu Dawei Tian Zhangqun Ye Zheng Liu Zhiping Wang Junqiang Tian Lin Qi Minfeng Chen Wei Li Jinchun Qi Gongxian Wang Longlong Fu Zhaolin Sun Guangheng Luo Zhoujun Shen Zhaowei Zhu Jinchun Xing Zhun Wu Dong Wei Xin Chen Yanqun Na Hongfeng Guo Chunxi Wang Zhihua Lu Chuize Kong Yang Liu Jin Yang Jianyun Hu Xin Gao Jielin Li Changjun Yin Pu Li Shan Chen Zhen Du Jiongming Li Yongji Yan Xu Zhang Shuang Huang Fangjian Zhou Zhiling Zhang Yinghao Sun Shuxiong Zeng Song Cen Jiaquan Zhou Hanzhong Li Jin Wen Jian Huang 2015Asian Journal of Urology2015,2,2:21
5Mid—Late Neoproterozoic rift-related volcanic rocks in China:Geological records of rifting and break-up of Rodinia显示文摘Early Cambrian and Mid-Late Neoproterozoic volcanic rocks in China are widespread on several Precambrian continental blocks,which had aggregated to form part of the Rodinia supercontinent by ca.900 Ma.On the basis of petrogeochemical data,the basic lavas can be classified into two major magma types:HT(Ti/Y>500) and LT(Ti/Y<500) that can be further divided into HT1 (Nb/La>0.85) and HT2(Nb/La≤0.85),and LT1(Nb/La>0.85) and LT2(Nb/La≤0.85) subtypes, respectively.The geochemical variation of the HT2 and LT2 lavas can be accounted for by lithospheric contamination of asthenosphere-(or plume-) derived magmas,whereas the parental magmas of the HT1 and LT1 lavas did not undergo,during their ascent,pronounced lithospheric contamination.These volcanics exhibit at least three characteristics:(1) most have a compositional bimodality;(2) they were formed in an intracontinental rift setting;and(3) they are genetically linked with mantle plumes or a mantle surperplume.This rift-related volcanism at end of the MidNeoproterozoic and Early Cambrian coincided temporally with the separation between AustraliaEast Antarctica,South China and Laurentia and between Australia and Tarim,respectively. The Mid—Late Neoproterozoic volcanism in China is the geologic record of the rifting and break-up of the supercontinent Rodinia.Linqi Xia Zuchun Xia Xueyi Xu Xiangmin Li Zhongping Ma 2012Geoscience Frontiers2012,3,4:18
6Advances in design theories of high-speed railway ballastless tracks显示文摘The design theories of the ballastless track in the world are reviewed in comparison with the innovative research achievements of high-speed railway ballastless track in China.The calculation methods and parameters concerning train load,thermal effect,and foundation deformation of high-speed railway ballastless track,together with the structural design methods are summarized.Finally,some suggestions on the future work are provided.Xueyi LIU Pingrui ZHAO Feng DAI 2011Journal of Modern Transportation2011,19,3:16
7Relationships between Basic and Silicic Magmatism in Continental Rift Settings:A Petrogeochemical Study of Carboniferous Post-collisional Rift Silicic Volcanics in Tianshan,NW China显示文摘Petrogeochemical data are reported for silicic volcanic rocks from the Tianshan Carboniferous rift, with the aim of discussing the petrogenesis of silicic magmas. Incompatible element vs. incompatible element diagrams display smooth positive trends for the Tianshan Carboniferous rift-related volcanic rocks; the isotope ratios of the silicic lavas [87Sr/86Sr(t)=0.69988–0.70532; εNd(t)=4.76–8.00; 206Pb/204Pb(t)=17.435–18.017; 207Pb/204Pb(t)=15.438–15.509; 208Pb/204Pb(t) = 37.075–37.723] encompass those of the basic lavas. These data suggest a genetic link between rhyolites and basalts, but are not definitive in establishing whether silicic rocks are related to basalts through fractional crystallization or partial melting. Geochemical modeling of incompatible vs. compatible elements excludes the possibility that silicic melts are generated by the melting of basaltic rocks, and indicates a derivation by fractional crystallization plus moderate assimilation of wall rocks (AFC) starting from intermediate rocks to silicic rocks. Continuous AFC from basalt to rhyolite, with small rates of crustal assimilation, best explains the geochemical data. The presence or absence of bimodal volcanism (the “Daly Gap”) might be related to cooling rates of magma chambers. In central and eastern Tianshan, the crust was thinner and the cooling rates of the magma chamber within the crust were greater. These conditions resulted in a rapid fall in temperature within the magma reservoir and caused a narrow temperature interval over which intermediate melts formed, effectively reducing the volume of the intermediate melts.XIA Linqi XIA Zuchun XU Xueyi LI Xiangmin MA Zhongping WANG Lishe 2005Acta Geologica Sinica(English Edition)2005,79,5:14
8Experimental study of temperature gradient in track slab under outdoor conditions in Chengdu area显示文摘Temperature is one of the important loads for designing slab track. The characteristic of slab track temperature varies greatly with different regional climates. In this work, a bi-block slab track model was built under outdoor conditions in Chengdu area; the statistical characteristic of temperature gradient in track slab and the relationship between temperature gradient and surface air temperature were tested and analyzed. The results show that the track slab temperature gradient will vary periodically according to the surface air temperature, and show a clear nonlinearity along the height direction. The temperature gradient distribution is extremely uneven: the temperature gradient in the top part of the track slab is larger than that in the bottom part; the most frequently occurring temperature gradient of the track slab is around-3.5 °C/m and more than75 % locates in the level-10 to 10 °C/m; concrete with a relatively good heat exchange condition with the surrounding air has a narrower band distribution. In addition, the frequency distribution histogram should exclude the time zone from 00:00 to 06:00 because there is almost no traffic in this period. The amplitude of track slab temperature variation is obviously lower than that of the air temperature variation, and the former is approximately linear with the latter.Pingrui Zhao Xueyi Liu Guan Liu 2014Journal of Modern Transportation2014,22,3:12
9SARS-Coronavirus-2 Nsp13 Possesses NTPase and RNA Helicase Activities That Can Be Inhibited by Bismuth Salts显示文摘The ongoing outbreak of Coronavirus Disease 2019(COVID-19)has become a global public health emergency.SARScoronavirus-2(SARS-CoV-2),the causative pathogen of COVID-19,is a positive-sense single-stranded RNA virus belonging to the family Coronaviridae.For RNA viruses,virus-encoded RNA helicases have long been recognized to play pivotal roles during viral life cycles by facilitating the correct folding and replication of viral RNAs.Here,our studies show that SARS-CoV-2-encoded nonstructural protein 13(nsp13)possesses the nucleoside triphosphate hydrolase(NTPase)and RNA helicase activities that can hydrolyze all types of NTPs and unwind RNA helices dependently of the presence of NTP,and further characterize the biochemical characteristics of these two enzymatic activities associated with SARS-CoV-2 nsp13.Moreover,we found that some bismuth salts could effectively inhibit both the NTPase and RNA helicase activities of SARS-CoV-2 nsp13 in a dose-dependent manner.Thus,our findings demonstrate the NTPase and helicase activities of SARS-CoV-2 nsp13,which may play an important role in SARS-CoV-2 replication and serve as a target for antivirals.Ting Shu Muhan Huang Di Wu Yujie Ren Xueyi Zhang Yang Han Jingfang Mu Ruibing Wang Yang Qiu Ding-Yu Zhang Xi Zhou 2020Virologica Sinica2020,35,3:11
10Discovery of ~4.0 Ga detrital zircons in the Aermantai ophiolitic mélange,East Junggar,northwest China显示文摘The East Junggar is an important part of the Central Asian Orogenic Belt(CAOB).Using in situ zircon dating and Hf isotopic analysis by LA-ICP-MS and MC-ICP-MS,respectively,a detrital zircon of 4040 Ma age was found in sedimentary sequences from the Aermantai ophiolitic mélange,East Junggar.This is the oldest age record in the East Junggar terrane,and also marks the first zircon locality in the CAOB with an age older than 4.0 Ga,which is attributed to the Hadean crust.The 4040 Ma detrital zircon has anεHf(t)value of–5.2 and a two-stage Hf modal age of 4474 Ma,suggesting the presence of very old(Hadean)crustal material in the source area.Beside peak ages of 446 Ma,we found four age groups of 3.6–3.1 Ga,2.53–2.37 Ga,1.14–0.89 Ga and 0.47–0.42 Ga from 141 effective measuring points.The age of 426±4 Ma for the five youngest detrital zircons defines the lower limit of the deposition time of sedimentary sequencess in the Aermantai ophiolitic mélange.The 0.47–0.42 Ga zircons exhibit176Hf/177Hf ratios of 0.282156 to 0.282850,corresponding to variableεHf(t)values from–9.3 to 12.0 and Hf model ages from2011 to 646 Ma.These characteristics are similar to those of the early Paleozoic igneous and gneissic zircons from the Altai,but significantly different from those of the East Junggar.Based on the material structures of felspathic greywacke,the morphology,internal texture and age distributions of dated detrital zircons,in combination with a study of the regional geological data,it is suggested that the sedimentary sequences in the Aermantai ophiolitic mélange was deposited in the Late Silurian,with the main provenance from the Altai Orogen in the north.This indicates that the early Paleozoic ocean represented by the Aermantai ophiolitic mélange was readily closed during the Late Silurian,and the northern edge of the East Junggar terrane was accreted to the Altai Orogen.The joint of them then served as a marginal orogen in the southern edge of the Siberia Paleocontinent.HUANG Gang NIU GuangZhi ZHANG ZhanWu WANG XinLu XU XueYi GUO Jun YU Feng 2013Chinese Science Bulletin2013,58,30:9
11Establishing a human pancreatic stem cell line and transplanting induced pancreatic islets to reverse experimental diabetes in rats显示文摘The major obstacle in using pancreatic islet transplantation to cure type I and some type II diabetes is the shortage of the donors. One of ways to overcome such obstacle is to isolate and clone pancreatic stem cells as 'seed cells' and induce their differentiation into functional islets as an abundant trans-plantation source. In this study, a monoclonal human pancreatic stem cell (mhPSC) line was obtained from abortive fetal pancreatic tissues. Pancreatic tissues were taken from abortive fetus by sterile procedures, and digested into single cells and cell clusters with 0.1% type IV collagenase. Cultured in modified glucose-low DMEM with 10% fetal bovine serum (FBS), these single cells and cell clusters adhered to culture dishes, and then primary epidermal-like pancreatic stem cells started to clone. After digesting with 0.25% trypsin and 0.04% EDTA, fibroblasts and other cells were gradually eliminated and epithelioid pancreatic stem cells were gradually purified during generations. Using clone-ring selection, the mhPSCs were obtained. After addition of 10 ng/mL epidermal growth factor (EGF) in cell culture medium, the mhPSCs quickly grew and formed a gravelstone-like monolayer. Continuously proliferated, a mhPSC line, which was derived from a male abortive fetus of 4 months old, has been passed through 50 generations. More than 1×109 mhPSCs were cryo-preserved in liquid nitrogen. Karyotype analysis showed that the chromosome set of the mhPSC line was normal diploid. Immunocytochemistry results demonstrated that the mhPSC line was positive for the pdx1, glucagon, nestin and CK19, and negative for the insulin, CD34, CD44 and CD45 protein expression. RT-PCR revealed further that the mhPSCs expressed transcription factors of the pdx1, glucagon, nestin and CK19. Also, in vitro induced with β-mercaptoethanol, the mhPSCs differentiated into nerve cells that expressed the NF protein. Induced with nicotinamide, the mhPSCs differentiated into functional islet-like clusters, as identified by di-thizone staining, which expressed the transcription factor of the insulin and secreted the insulin and C-peptide. Furthermore, the transplantation of mhPSCs-induced pancreatic islets into the subcapsular region of the kidney in streptozotocin-induced diabetic rats could reduce blood glucose levels and prolong the life time.XIAO Mei AN LiLong YANG XueYi GE Xin QIAO Hai ZHAO Ting MA XiaoFei FAN JingZhuang ZHU MengYang DOU ZhongYing 2008Science China(Life Sciences)2008,51,9:9
122D Layered Double Hydroxide Nanosheets and Their Derivatives Toward E cient Oxygen Evolution Reaction显示文摘Layered double hydroxides(LDHs)have attracted tremendous research interest in widely spreading applications.Most notably,transition-metal-bearing LDHs are expected to serve as highly active electrocatalysts for oxygen evolution reaction(OER)due to their layered structure combined with versatile com-positions.Furthermore,reducing the thickness of platelet LDH crystals to nanometer or even molecular scale via cleavage or delamination provides an important clue to enhance the activity.In this review,recent progresses on rational design of LDH nanosheets are reviewed,including direct synthesis via traditional coprecipitation,homogeneous precipitation,and newly developed topochemical oxidation as well as chemical exfoliation of parent LDH crystals.In addition,diverse strategies are introduced to modulate their electrochemical activity by tuning the composition of host metal cations and intercalated counter-anions,and incorporating dopants,cavi-ties,and single atoms.In particular,hybridizing LDHs with conductive components or in situ growing them on conductive substrates to produce freestanding electrodes can further enhance their intrinsic catalytic activity.A brief discussion on future research directions and prospects is also summarized.Xueyi Lu Hairong Xue Hao Gong Mingjun Bai Daiming Tang Renzhi Ma Takayoshi Sasaki 2020Nano-Micro Letters2020,12,7:8
13Insights into the mechanism of CXCL12-mediated signaling in trophoblast functions and placental angiogenesis显示文摘chemokine CXCL12 和它的受体 CXCR4 是重要的表明为人的胚囊培植和怀孕的前进要求的部件。成长证据显示 CXCL12/CXCR4 轴能调整 trophoblast 功能和改变的子宫的螺线动脉,它在胎座式和胎儿的结果起一个基本作用。孤儿受体 CXCR7 也被相信部分调整 CXCL12/CXCR4 轴的功能。另外, CXCL12/CXCR4/CXCR7 轴能提高在象子宫的自然漂亮房间那样的 trophoblasts 和蜕膜的房间和涉及 trophoblast 区别和侵略和胎盘的 angiogenesis 的规定的蜕膜的 stromal 房间之间的串音。另外,最近的研究证明那 CXCL12 表情与 preeclampsia 在胎盘和怀孕女人的中间三个月的羊膜的液体被提高,暗示 CXCL12 的 dysregulation 起在 preeclampsia 的致病的一个作用。在 trophoblast 功能和胎盘的 angiogenesis 的调停 CXCL12 的发信号的规章的机制的进一步的理解可以帮助为联系怀孕的疾病设计新奇治疗学的途径。Liang Wang Xueyi Li Yilin Zhao Chao Fang Yingli Lian Wenli Gou Tao Han Xiaoming Zhu 2015Acta Biochimica et Biophysica Sinica2015,47,9:8
14The geochemical characteristics,geochronology and tectonic significance of the Carboniferous volcanic rocks of the Santanghu area in northeastern Xinjiang,China显示文摘The Santanghu area is located on the northeastern margin of the Junggar Basin,northern Xinjiang,Northwest China.The Carboniferous volcanic rocks in this area are widely distributed in Kaokesaiergaishan,Santanghu,Daheishan and Naomaohu districts,which are located to the north of the Kalameili Fault.These rocks,sourced from a cognate magma,consist of basic,intermediate,and acidic lavas,and pyroclastic rock.The basic volcanic rocks are enriched with large-ion lithophile elements(LILE),but are relatively depleted in high field strength elements(HFSE),and have an obvious negative Nb-Ta-Ti anomaly.They were most probably derived from a depleted mantle source,and during their ascent,these magmas were not contaminated by the crustal material as they underwent magma crystallization differentiation.Based on the Carboniferous volcanic assemblage and geochemical data,it is apparent that the early Carboniferous volcanism occurred in a subduction-related tectonic setting.New LA-ICP-MS zircon U-Pb analyses constrain the age of the andesite within the volcanic rocks as the early Carboniferous(328.9-331.3 Ma).Combined with the regional geological record,comprehensive analysis of the isotope geochronological data indicates that the subduction of the Junggar Ocean predates the early Carboniferous,and that the Santanghu island arc magmatism was induced by the subduction of the Junggar Ocean in the Carboniferous.LI Wei LIU YiQun DONG YunPeng ZHOU XiaoHu LIU XiaoMing LI Hong FAN TingTing ZHOU DingWu XU XueYi CHEN JunLu 2013Science China Earth Sciences2013,56,8:8
15Are small RNAs a big help to plants?显示文摘The discovery of RNA interference(RNAi) has augmented our knowledge of gene regulation and presents a fascinating technology that has a great potential for application in genetic analysis,disease therapy,plant protection,and many other areas.In this review,we will focus on the biological functions of RNAi and its application in agriculture with a brief introduction to the history of its discovery and molecular mechanism.MAO YingBo,XUE XueYi & CHEN XiaoYa National Key Laboratory of Plant Molecular Genetics,Institute of Plant Physiology and Ecology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200032,China 2009Science China(Life Sciences)2009,52,3:7
16Three-dimensional bioprinted glioblastoma microenvironments model cellular dependencies and immune interactions显示文摘Brain tumors are dynamic complex ecosystems with multiple cell types.To model the brain tumor microenvironment in a reproducible and scalable system,we developed a rapid three-dimensional(3D)bioprinting method to construct clinically relevant biomimetic tissue models.In recurrent glioblastoma,macrophages/microglia prominently contribute to the tumor mass.To parse the function of macrophages in 3D,we compared the growth of glioblastoma stem cells(GSCs)alone or with astrocytes and neural precursor cells in a hyaluronic acid-rich hydrogel,with or without macrophage.Bioprinted constructs integrating macrophage recapitulate patient-derived transcriptional profiles predictive of patient survival,maintenance of stemness,invasion,and drug resistance.Whole-genome CRISPR screening with bioprinted complex systems identified unique molecular dependencies in GSCs,relative to sphere culture.Multicellular bioprinted models serve as a scalable and physiologic platform to interrogate drug sensitivity,cellular crosstalk,invasion,context-specific functional dependencies,as well as immunologic interactions in a species-matched neural environment.Min Tang Qi Xie Ryan C.Gimple Zheng Zhong Trevor Tam Jing Tian Reilly L.Kidwell Qiulian Wu Briana C.Prager Zhixin Qiu Aaron Yu Zhe Zhu Pinar Mesci Hui Jing Jacob Schimelman Pengrui Wang Derrick Lee Michael H.Lorenzini Deobrat Dixit Linjie Zhao Shruti B.hargava Tyler E.Miller Xueyi Wan Jing Tang Bingjie Sun Benjamin F.Cravatt Alysson R.Muotri Shaochen Chen Jeremy N.Rich 2020Cell Research2020,30,10:6
17Geology and geochemistry of the Bingdaban ophiolitic mélange in the boundary fault zone on the northern Central Tianshan Belt,and its tectonic implications显示文摘The properties and tectonic significance of the fault bound zone on the northern margin of the Central Tianshan belt are key issues to understand the tectonic framework and evolutionary history of the Tianshan Orogenic Belt. Based on the geological and geochemical studies in the Tianshan orogenic belt, it is suggested that the ophiolitic slices found in the Bingdaban area represent the remaining oceanic crust of the Early Paleozoic ocean between the Hazakstan and Zhungaer blocks. Mainly com-posed of basalts, gabbros and diabases, the ophiolites were overthrust onto the boundary fault be-tween the Northern Tianshan and Central Tianshan belts. The major element geochemistry is charac-terized by high TiO2 (1.50%-2.25%) and MgO (6.64%-9.35%), low K2O (0.06%-0.41%) and P2O5 (0.1%-0.2%), and Na2O>K2O as well. Low ΣREE and depletion in LREE indicate that the original magma was derived from a depleted mantle source. Compared with a primitive mantle, the geochemistry of the basalts from the Bingdaban area is featureded by depletion in Th, U, Nb, La, Ce and Pr, and unfrac-tionated in HFS elements. The ratios of Zr/Nb, Nb/La, Hf/Ta, Th/Yb and Hf/Th are similar to those of the typical N-MORB. It can be interpreted that the basalts in the Bingdaban area were derived from a de-pleted mantle source, and formed in a matured mid-oceanic ridge setting during the matured evolu-tionary stage of the Northern Tianshan ocean. In comparison with the basalts, the diabases from the Bingdaban area show higher contents of Al2O3, ∑REE and HFS elements as well as unfractionated incompatible elements except Cs, Rb and Ba, and about 10 times the values of the primitive mantle. Thus, the diabases are thought to be derived from a primitive mantle and similar to the typical E-MORB. The diabases also have slight Nb depletion accompanying no apparent Th enrichment compared with N-MORB. From studies of the regional geology and all above evidence, it can be suggested that the diabases from the Bingdaban area were formed in the mid-oceanic ridge of the Northern Tianshan ocean during the initial spreading stage.DONG YunPeng ZHANG GuoWei ZHOU DingWu LUO JinHai ZHANG ChengLi XIA LinQi XU XueYi LI XiangMin 2007Science China Earth Sciences2007,50,1:5
18Fluids and Melts in the Upper Mantle显示文摘This paper presents a direct study of the fluids and melts in the upper mantle by examining the fluid inclusions, melt inclusions and glasses trapped in the mantle lherzolite xenoliths entrained by Cenozoic alkali basalts (basanite, olivine-nephelinite and alkali-olivine basalt) from eastern China. The study indicates that the volatile components, which are dissolved in high-pressure solid mineral phases of mantle peridotite at depths, may be exsolved under decompressive conditions of mantle plume upwelling to produce the initial free fluid phases in the upper mantle. The free fluid phases migrating in the upper mantle may result in lowering of the mantle solidus (and liquidus), thereby initiating partial melting of the upper mantle, and in the meantime, producing metasomatic effects on the latter.XIA Linqi XIA Zuchun XU Xueyi 1999Acta Geologica Sinica(English Edition)1999,73,3:4
19Intramolecular aromatic-ring stacking interaction of ternary Zn(UTP)L^(2-) complexes显示文摘THE mechanism of the action of the classic platinum antitumor drugs can be interpreted accord-ing to their bidentate, bifunctional interaction with the DNA of the tumor cell, resulting in in-hibition of the DNA replication. Recently, it was found that a new class of compounds withthe general formula cis-[Pt(NH3)2(N-het)Cl]Cl(N-het is a heteroaromatic N-base like pyri-dine) show effective antitumor activities. However, two possible mechanisms of actionLE Xueyi, WU Fuhai, SONG Fenyun and Jl Liangnian1.Department of Chemistry, Zhongshan University, Guangzhou 510275, China State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China 2. Department of Hygienics, Guangdong Pharmaceutical School, Guangzhou 510224, China 1997Chinese Science Bulletin1997,42,14:4
20Synthesis of layered double hydroxides/graphene oxide nanocomposite as a novel high-temperature CO_2 adsorbent显示文摘In this contribution, a novel high-temperature CO2 adsorbent consisting of Mg-Al layered double hydroxide(LDH) and graphene oxide(GO)nanosheets was prepared and evaluated. The nanocomposite-type adsorbent was synthesized based on the electrostatically driven self-assembly between positively charged Mg-Al LDH single sheet and negatively charged GO monolayer. The characteristics of this novel adsorbent were investigated using XRD, FE-SEM, HRTEM, FT-IR, BET and TGA. The results showed that both the CO2 adsorption capacity and the multicycle stability of LDH were increased with the addition of GO owing to the enhanced particle dispersion and stabilization. In particular, the absolute CO2 capture capacity of LDH was increased by more than twice by adding 6.54 wt% GO as support. GO appeared to be especially effective for supporting LDH sheets. Moreover, the CO2 capture capacity of the adsorbent could be further increased by doping with 15 wt%K2CO3. This work demonstrated a new approach for the preparation of LDH-based hybrid-type adsorbents for CO2 capture.Junya Wang Xueyi Mei Liang Huang Qianwen Zheng Yaqian Qiao Ketao Zang Shengcheng Mao Ruoyan Yang Zhang Zhang Yanshan Gao Zhanhu Guo Zhanggen Huang Qiang Wang 2015Journal of Energy Chemistry2015,24,2:4
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