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30篇 您的检索式:作者名="Yongsheng Meng"
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1In-situ U-Pb dating of uraninite by fs-LA-ICP-MS显示文摘In this study,the Pb/U fractionation between zircon and uraninite during femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry(fs-LA-ICP-MS)analysis was studied in detail.The results show significant Pb/U fractionation between zircon and uraninite during fs-LA-ICP-MS analysis that when calibrated against the zircon standard M257,the obtained U-Pb age of the Chinese national uraninite standard GBW04420 is 17%older than the recommended value.Thus,the accurate in-situ U-Pb dating of uraninite by LA-ICP-MS requires matrix-matched external standards for calibration.Uraninite in thin sections of two U-mineralized leucogranite from the Gaudeanmus in Namibia was analyzed by a fs-LA-ICP-MS equipped with a Signal Smooth Device(SSD),using laser spot and frequency of 10μm and 1 Hz,respectively.When calibrated using GBW04420 as the external standard,two samples give weighted mean 206Pb/238U ages of 504±3 Ma(2σ,n=21)and503±3 Ma(2σ,n=22),and only one of two samples yields a concordia U-Pb age of 507±1 Ma(2σ,n=21).These results are consistent with ID-TIMS U-Pb ages of 509±1 and 508±12 Ma and are also indistinguishable from zircon U-Pb upper intercept ages of 506±33 Ma(2σ,n=29)and 501±51 Ma(2σ,n=29).The present study shows that in-situ U-Pb dating of uraninite can deliver more reliable formation ages of the deposit than dating coeval high-U zircon because the latter commonly suffer significant Pb loss after formation.Our results confirm that GBW04420 is an ideal matrix matching standard for in-situ U-Pb dating of uraninite.ZONG KeQing CHEN JinYong HU ZhaoChu LIU YongSheng LI Ming FAN HongHai MENG YanNing 2015Science China Earth Sciences2015,58,10:22
2Deep carbon cycles constrained by a large-scale mantle Mg isotope anomaly in eastern China显示文摘Although deep carbon recycling plays an important role in the atmospheric CO_2 budget and climate changes through geological time,the precise mechanisms remain poorly understood.Since recycled sedimentary carbonate through plate subduction is the main light-δ^(26)Mg reservoir within deep-Earth,Mg isotope variation in mantle-derived melts provides a novel perspective when investigating deep carbon cycling.Here,we show that the Late Cretaceous and Cenozoic continental basalts from 13 regions covering the whole of eastern China have low δ^(26)Mg isotopic compositions,while the Early Cretaceous basalts from the same area and the island arc basalts from circum-Paciic subduction zones have mantle-like or heavy Mg isotopic characteristics.hus,a large-scale mantle low δ^(26)Mg anomaly in eastern China has been delineated,suggesting the contribution of sedimentary carbonates recycled into the upper mantle,but limited into the lower mantle.his large-scale spatial and temporal variation of Mg isotopes in the mantle places severe constraints on deep carbon recycling via oceanic subduction.Shu-Guang Li Wei Yang Shah Ke Xunan Meng Hengci Tian Lijuan Xu Yongsheng He Jian Huang Xuan-Ce Wang Qunke Xia Weidong Sun Xiaoyong Yang Zhong-Yuan Ren Haiquan Wei Yongsheng Liu Fancong Meng Jun Yan 2017National Science Review2017,4,1:23
3Dendritic cell-based vaccination with lentiviral vectors encoding ubiquitinated hepatitis B core antigen enhances hepatitis B virus-specific immune responses in vivo显示文摘肝炎 B 病毒(HBV ) 的活动特定的细胞毒素的 T 淋巴细胞(CTL ) 戏在 HBV 的清理的一个占优势的角色。树枝状的房间(DC ) 是关键介绍抗原的房间并且在有免疫力的回答的开始起一个重要作用。我们以前验证了有效地编码 ubiquitinated 肝炎 B 核心抗原(LV-Ub-HBcAg ) 的那 lentiviral 向量导致成熟的 transduced DC,和成熟 DC 高效地导致了 T 房间极化到 Th1 并且产生了 HBcAg 特定的 CTL 前 vivo。在这研究,在 BALB/c 老鼠的 LV-Ub-HBcAg 的 HBV 特定的有免疫力的回答(H-2K d ) 被评估。LV-Ub-HBcAg 的直接注射增加了 cytokines IL-2 和 IFN- 的生产,这被显示出,得到了强壮的抗体回答,并且显著地产生了 IFN-+ 有在 BALB/c 老鼠的 HBV 特定的 CTL 回答的 CD8 + T 房间。另外, LV-Ub-HBcAg 的直接注射导致了有势力 anti-HBV 免疫者回答,类似于得到由的那些在 vitro-transduced DC。在结论,基于 DC 的治疗学的疫苗的 LV-Ub-HBcAg 得到了特定的抗体免疫者回答并且在 vivo 导致了柔韧的特定的 CTL 活动。Shenglan Dai Meng Zhuo Linlin Song Xiaohua Chen Yongsheng Yu Zhenghao Tang Guoqing Zang 2015Acta Biochimica et Biophysica Sinica2015,47,11:9
4Discovery of marine fossils in the upper part of the Permian Linxi Formation in Lopingian, Xingmeng area, China显示文摘Two important geological issues have a long history of debate in the Xingmeng area.The first concerns the final closure of the North China plate,Siberia plate and several intermediate massifs in the area,and the other concerns the folding and lifting of the Xingmeng Trough.Disagreements arise because of issues involving the tectonicpalaeogeographical environment of the Upper Permian deposits of the Linxi Formation.The Linxi Formation(Upper Permian)is generally considered to be either an exclusively continental deposit or separated into marineterrigenous facies deposited during the Lower to Middle Linxi Period and continental deposits in the Upper Linxi Period.However,in this study,large numbers of bryozoan and sponge spicule fossils were discovered for this first time in the thick limestone layers and lenses of the upper part of the Linxi Formation found in the Guandi section of Linxi county in eastern Inner Mongolia.At the same time,abundant bryozoan fossils were also found in sedimentary tuff slices that were collected from the upper part of the Taohuayingzi Formation from the Taohuayingzi section in Ar Horqin Banner,and abundant small connecting body crinoid stem fossils were found in the dark shale of the Yangjiagou Formation from the Yangjiagou section of Jiutai county,Jilin Province.These marine fossils provide the first evidence that the Xingmeng area was still a marine or mainly marine environment at the end of the late Permian.This not only provides conclusive evidence for the recognition of the above two major geological issues but also promotes changes in the approach towards research,exploration and development of oil and gas,shale gas(oil),and other mineral resources that are preserved in the late Permian layers of the Northeast-Xingmeng area.Yongsheng Zhang Shugang Tian Zishun Li Yuexuan Gong Enyuan Xing Zhuozhuo Wang Daxing Zhai Cao Jie Su Kui Wang Meng 2014Chinese Science Bulletin2014,59,1:6
5From Basin Black Shales to Platform Carbonate Rocks:A Study on Sequence Stratigraphy for the Lower Cambrian of the Upper-Yangtze Region in South China显示文摘在 Upper-Yangtze 区域,特别在贵州省和它的邻近的区域,更低寒武纪很好被开发并且由从盆外形的黑页岩的继任是显著的焦化站台外形的岩石。从 Sinian 发生在拐弯到的站台的淹死的事件寒武纪导致了一套黑页岩,即 Niutitang 形成,它完成底部部分更低寒武纪。与沉积环境变浅,一套碳酸盐摇,即 Qingxudong 形成,在最高的部分被形成更低寒武纪。因此,更低在学习区域寒武纪使能进一步的一个秒顺序序列起来细分进五个第三顺序的序列,并且形成违反回归的定期周期的继任。为在秒顺序顺序的第三顺序的序列有一个定期垂直的叠模式。从底部到顶,继任“ CS (压缩的节)+HST (高看台的系统道) ”第三顺序的序列被变成继任“ TST (transgressive 系统道)+CS+HST' 。相应地,淹死类型顺序边界被变成暴露类型那条。因此,秒顺序和第三顺序的序列有类似的沉积外形的体系结构。有这些时间的变化的伴随物,更低与包含五个第三顺序的序列的 1000 m 的厚度寒武纪被变成不能与加深沉积环境向东南识别第三顺序的序列的压缩继任。根据第三顺序的序列的基本特征,即整齐 o 在空间和沉积环境的变化的同步性的沉积外形的继任及时,在在不同 paleogeographical 背景的主要的记载的节的第三顺序的序列的详细部门成为基础建立能在 stratigraphic 记录表明改变外形的表面的二种类型和 diachronism 的二种类型的 sequence-stratigraphic 框架。这个 sequence-stratigraphic 框架从盆外形的黑页岩形成的压缩继任的库显示出碳酸盐平台的成长进程。从 Sinian 在拐弯源于快速的违反到寒武纪生态的空间变得开,它形成了为“寒武纪的生物爆炸”设定的 paleogeographical 的先前的条件。最终,在 depositional 事件之间的基因关系和生物差异的事件是很复杂的并且在那里仍然是以后需要推进研究的大量问题。MEI Mingxiang MA Yongsheng ZHANG Hai MENG Xiaoqing CHEN Yonghong 2007Acta Geologica Sinica(English Edition)2007,81,5:6
6A general strategy for bimetallic Pt-based nano-branched structures as highly active and stable oxygen reduction and methanol oxidation bifunctional catalysts显示文摘The morphology and size of Pt-based bimetallic alloys are known to determine their electrocatalytic performance in reactions relevant to fuel cells.Here,we report a general approach for preparing Pt-M(M=Fe,Co and Ni)bimetallic nano-branched structure(NBs)by a simple high temperature solution-phase synthesis.As-prepared Pt-M NBs show a polycrystalline structure and are rich in steps and kinks on the surface,which promote them favorable bifunctional catalytic properties in acidic electrolytes,specifically in terms of the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR).Specially,Pt-Co NBs/C catalyst shows 6.1 and 5.3 times higher in specific activity(SA)and mass activity(MA)for ORR than state-of-the-art commercial Pt/C catalysts,respectively.Moreover,it exhibits a loss of 4.0%in SA and 14.4%in MA after 10,000 cycles of accelerated durability tests(ADTs)compared with the initial activities.In addition,we also confirmed the superior MOR activity of Pt-Co NBs/C catalyst in acidic electrolytes.For Pt-M NBs with other alloying metals,the ORR and MOR activities are both higher than commercial catalysts and are in the sequence of Pt-Co/C>Pt-Fe/C>Pt-Ni/C>commercial Pt/C(or PtRu/C).The improved activities and durability can benefit from the morphological and compositional effects.This synthesis approach may be applied to develop bifunctional catalysts with enhanced ORR and MOR properties for future fuel cells designs.Wenjuan Lei Menggang Li Lin He Xun Meng Zijie Mu Yongsheng Yu Frances MRoss Weiwei Yang 2020Nano Research2020,13,3:5
7LeCDJ1,a chloroplast DnaJ protein,facilitates heat tolerance in transgenic tomatoes显示文摘The roles of a tomato(Lycopersicon esculentum) chloroplast-targeted DnaJ protein(LeCDJ1) were investigated using wild-type(WT) and sense transgenic tomatoes. The LeCDJ1 expression was upregulated by 38 °C, 42 °C, 45 °C, NaCl, PEG, methyl viologen(MV) and hydrogen peroxide(H2 O2), but not by 30 °C and 35 °C. Meanwhile, LeCDJ1 was involved in the response of plants to abscisic acid(ABA). Under heat stress, the sense plants showed better growth, higher chlorophyll content, lower malondialdehyde(MDA) accumulation and relative electrical conductivity(REC), and also less PSII photoinhibition than WT. Interestingly, the sense plants treated with streptomycin(SM), an inhibitor of organellar translation, still showed higher maximum photochemistry efficiency of PSII(Fv/Fm) and D1 protein levels than the SM-untreated WT, suggesting that the protective effect of LeCDJ1 on PSII was, at least partially, independent of D1protein synthesis. Furthermore, the relatively lower superoxide radical(O2·-) and H2 O2 levels in the sense plants were considered to be due to the higher ascorbate peroxidase(APX) and superoxide dismutase(SOD) activity, which seemed unlikely dependent on their transcription level. These results indicated that LeCDJ1 overexpression facilitated heat tolerance in transgenic tomatoes.Fanying Kong Yongsheng Deng Guodong Wang Jieru Wang Xiaoqing Liang Qingwei Meng 2014Journal of Integrative Plant Biology2014,56,1:5
8Recent progress in organic solar cells(PartⅡdevice engineering)显示文摘1 Introduction Organic solar cells(OSCs)belong to a multidisciplinary field composed of chemistry,materials science,physics,engineering,etc.For a better reviewing of this field,we briefly divide the research field of OSCs into two parts:material science and device engineering.In our previous review,the material science part of OSCs,including conjugated polymer donors and acceptors,small molecular donors and acceptors.Yahui Liu Bowen Liu Chang-Qi Ma Fei Huang Guitao Feng Hongzheng Chen Jianhui Hou Lingpeng Yan Qingya Wei Qun Luo Qinye Bao Wei Ma Wei Liu Weiwei Li Xiangjian Wan Xiaotian Hu Yanchun Han Yaowen Li Yinhua Zhou Yingping Zou Yiwang Chen Yuqiang Liu Lei Meng Yongfang Li Yongsheng Chen Zheng Tang Zhicheng Hu Zhi-Guo Zhang Zhishan Bo 2022Science China Chemistry2022,65,8:3
9Proteomics provides individualized options of precision medicine for patients with gastric cancer显示文摘While precision medicine driven by genome sequencing has revolutionized cancer care,such as lung cancer,its impact on gastric cancer(GC)has been minimal.GC patients are routinely treated with chemotherapy,but only a fraction of them receive the clinical benefit.There is an urgent need to develop biomarkers or algorithms to select chemo-sensitive patients or apply targeted therapy.Here,we carried out retrospective analyses of 1,020 formalin-fixed,paraffin-embedded GC surgical resection samples from 5 hospitals and developed a mass spectrometry-based workflow for proteomic subtyping of GC.We identified two proteomic subtypes:the chemo-sensitive group(CSG)and the chemo-insensitive group(CIG)in the discovery set.The 5-year overall survival of CSG was significantly improved in patients who had received adjuvant chemotherapy after surgery compared with those who received surgery only(64.2%vs.49.6%;Cox P-value=0.002),whereas no such improvement was observed in CIG(50.0%vs.58.6%;Cox P-value=0.495).We validated these results in an independent validation set.Further,differential proteome analysis uncovered 9 FDA-approved drugs that may be applicable for targeted therapy of GC.A prospective study is warranted to test these findings for future GC patient care.Wenwen Huang Dongdong Zhan Yazhuo Li Nairen Zheng Xin Wei Bin Bai Kecheng Zhang Mingwei Liu Xuefei Zhao Xiaotian Ni Xia Xia Jinwen Shi Cheng Zhang Zhihao Lu Jiafu Ji Juan Wang Shiqi Wang Gang Ji Jipeng Li Yongzhan Nie Wenquan Liang Xiaosong Wu Jianxin Cui Yongsheng Meng Feilin Cao Tieliu Shi Weimin Zhu Yi Wang Lin Chen Qingchuan Zhao Hongwei Wang Lin Shen Jun Qin 2021Science China(Life Sciences)2021,64,8:3
10Recent progress in perovskite solar cells:material science显示文摘Perovskite solar cells represent a promising third-generation photovoltaic technology with low fabrication cost and high power conversion efficiency.In light of the rapid development of perovskite materials and devices,a systematic survey on the latest advancements covering a broad range of related work is urgently needed.This review summarizes the recent major advances in the research of perovskite solar cells from a material science perspective.The discussed topics include the devices based on different type of perovskites(organic-inorganic hybrid,all-inorganic,and lead-free perovskite and perovskite quantum dots),the properties of perovskite defects,different type of charge transport materials(organic,polymeric,and inorganic hole transport materials and inorganic and organic electron transport materials),counter electrodes,and interfacial materials used to improve the efficiency and stability of devices.Most discussions focus on the key progresses reported within the recent five years.Meanwhile,the major issues limiting the production of perovskite solar cells and the prospects for the future development of related materials are discussed.Jiang-Yang Shao Dongmei Li Jiangjian Shi Chuang Ma Yousheng Wang Xiaomin Liu Xianyuan Jiang Mengmeng Hao Luozheng Zhang Chang Liu Yiting Jiang Zhenhan Wang Yu-Wu Zhong Shengzhong(Frank)Liu Yaohua Mai Yongsheng Liu Yixin Zhao Zhijun Ning Lianzhou Wang Baomin Xu Lei Meng Zuqiang Bian Ziyi Ge Xiaowei Zhan Jingbi You Yongfang Li Qingbo Meng 2023Science China Chemistry2023,66,1:3
11Landscape and Fruit Developmental Regulation of Alternative Splicing in Tomato by Genome-Wide Analysis显示文摘In eukaryotes, alternative splicing(AS) is one of the posttranscriptional regulatory mechanisms that play important roles by generating transcriptome diversity. To obtain a global view of AS and its dynamics during tomato fruit development, we analyzed the AS events using a large amount of transcriptome datasets. Same with other plant species, about half of the expressed multiexonic genes were alternatively spliced in tomato. Besides that, our further analyzation of RNA-seq datasets of ovule and pericarp at early fruit developmental stages reveals that the dynamic alteration of AS events occurred in specific tissues and AS was regulated spatially and temporally during early fruit development in tomato. By investigating the sequence variations at splice sites causing differential AS events between tomato cultivar ‘Moneymaker' and wild species Solanum pimpinellifolium PI365967, we uncover that AS may play the regulatory roles during domestication of tomato. Taken together, our results provided the global AS pattern in tomato and highlighted the importance of AS during tomato fruit development and domestication.WANG Ketao JIAO Zhicheng XU Meng WANG Yongsheng LI Ren CUI Xia GU Lianfeng ZHANG Shuaibin 2016Horticultural Plant Journal2016,2,6:2
12The first extra-large helium-rich gas field identified in a tight sandstone of the Dongsheng Gas Field,Ordos Basin,China显示文摘Helium gas is a scarce but important strategic resource,which is usually associated with natural gas.Presently,only one extra-large helium-rich gas field has been found in China:the Hetianhe Gas Field in the Tarim Basin.This paper reports a new example,the Dongsheng Gas Field(DGF)in the Ordos Basin.In this study,92 natural gas samples from the DGF were analyzed for helium content and isotope composition using isotope mass spectrometry.The natural gas samples were found to have an average helium content of 0.133%,with 65(70.7%)of the samples having a helium content of 0.1%or more.Based on the proven natural gas reserves of the DGF,the proven geological helium reserves were calculated to be 1.96×10^(8)m^(3),suggesting that it represents the first extra-large helium-rich natural gas reservoir to be hosted in tight sandstone in China.The ^(3)He/^(4)He ratios of 5 natural gas samples from the DGF are within the range of 3.03×10^(−8)–3.44×10^(−8).Therefore,the helium in the gas field is thought to be of typical crustal origin and to have formed in the granitic basement that is rich in uranium and thorium.The accumulation of helium-rich natural gas was controlled by regional tectonic activities.Activity along the fault connecting the reservoir with the basement caused release of the helium gas,which entered the overlying strata along the fault and accumulated with conventional hydrocarbon gas.Based on the structural background and the distribution of helium source rocks in the Ordos Basin,the main helium source rocks with high exploration potential are located in deep strata within the north and middle parts of the basin.Weilong PENG Quanyou LIU Ying ZHANG Huichong JIA Dongya ZHU Qingqiang MENG Xiaoqi WU Shang DENG Yongsheng MA 2022Science China Earth Sciences2022,65,5:2
13Tandem organic solar cells with efficiency over 19% via the careful subcell design and optimization显示文摘The series-connected tandem device strategy is an effective approach to promote the efficiency of organic solar cells(OSCs) with broadened absorption range and alleviated thermalization and transmission loss.In this article,two nonfullerene acceptors,FB rThCl and BTP-4Se,with complementary absorptions covering the range from 300 to 1,000 nm were designed and synthesized for the front and rear cell,respectively.The front cell based on D18:FBr-ThCl exhibited a Voc of 1.053 V with high external quantum efficiency(EQE) response values ranging from 300 to 740 nm.The rear cell with a ternary active layer PM6:BTP-4 Se:F-2F was optimized and afforded the Voc of 0.840 V and Jsc of 26.88 mA cm^(-2).Subsequently,the tandem device was constructed with a fully solution-processed interconnected layer of ZnO/PEDOT:PS S/PMA,and demonstrated a power conversion efficiency(PCE) of 19.55% with a Voc of 1.880 V,a Jsc of 13.25 mA cm^(-2) and an FF of 78.47%.Lingxian Meng Huazhe Liang Guangkun Song Mingpeng Li Yuzhong Huang Changzun Jiang Kai Zhang Fei Huang Zhaoyang Yao Chenxi Li Xiangjian Wan Yongsheng Chen 2023Science China Chemistry2023,66,3:1
14Effect of end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture in pancreatic surgery显示文摘The aim of this paper is to summarize the methods of pancreaticojejunostomy in the pancreatic operation and to study the safety and feasibility of a new operative method called end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture to prevent fistula of pancreaticojejunostomy.Eight-three patients with pancreaticoduodenectomy in the 3rd Hospital,Jilin University from 2001 January to 2006 April were reviewed.The incidences of pancreatic fistula with different types of pancreaticojejunostomy were compared.The overall incidence rate of pancreatic fistula was 26.5%(22/83).No pancreatic fistula occurred in end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture.The incidence rate of the fistula following end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture was significantly lower than that of traditional end-to-end pancreaticojejunostomy[40%,(10/25),P<0.01]and end-to-side pancreaticojejunostomy[27.3%,(12/44),P<0.05],but no significant difference(P>0.05)between traditional end-to-end pancreaticojejunostomy and end-to-side pancreaticojejunostomy was discovered.End-to-end invagination pancreaticojejunostomy with circle discontinuous U suture has a definite effect on avoiding pancreatic fistula following pancreaticojejunostomy and is worth being recommended.But the cases were limited,so this method would still need to be observed and confirmed further in the future.ZHANG Xuewen XUAN Wei JIANG Tao JI Degang YANG Yongsheng ZHANG Dan XIE Yingjun MENG Zihui ZHAO Jisheng 2007Frontiers of Medicine2007,1,1:1
15Resveratrol displays converse dose-related effects on 5-fluorouracil-evoked colon cancer cell apoptosis: The roles of caspase-6 and p53显示文摘Jason Yongsheng Chan Meng Seng Phoo Marie-Veronique Clement Shazib Pervaiz Shao Chin Lee 2008Cancer Biology & Therapy2008,,:1
16Optical Storage Studies on the Trapping States of BaFCl:Eu^2+显示文摘Meng Xianguo Wang Yongsheng Sun Li 2003Journal of Physics:Condensed Matter2003,15,:1
17Coaxing Polysaccharide Granules into Supramolecular Biocolloidal Additives for Papermaking显示文摘In light of developments in polysaccharide-based sustainable processes involving supramolecular interactions,we herein present our findings pertaining to coaxing polysaccharide granules into functional supramolecular biocolloids.Translucent biocolloidal dispersions containing various forms of starch are facilely designable,essentially built upon complexation between disassembled native cornstarch granules and amphiphilic ligands.Oily moieties of guest molecules are dynamically attractable into cavities of helical structures,with cationic groups pointing toward the bulk phase.This noncovalent attraction can generate core-shell biocolloidal particles.The significantly higher gelatinizability of freeze-dried biocolloids in contrast to native cornstarch granules is attributable to complex formation,and a homogenous dispersion is readily formable at room temperature.Our results also show biocolloids'ligand-related antibacterial activity.The use of biocolloids as wet-end additives for biofiber assemblies(cellulosic paper)can enhance mechanical strength,fines retention,and filler bondability.Supramolecular biocolloids with positively charged,translucent,easily gelatinizable,antibacterial,and polysaccharide-bondable functionalities would find tailorable use in the paper industry.Yongsheng Wang Wenyuan Zhu Xueren Qian Meiyun Zhang Shunxi Song Chuyan Jing Zhengren Meng Shiyu Xu Xianhui An Xiujie Huang Jing Shen 2020Paper And Biomaterials2020,5,2:1
18Sedimentary Facies Architectures of Third-Order Sequences from Early to Middle Triassic in Nanpanjiang Basin显示文摘There are complex and regular changes on sedimentary facies from the Early to the Middle Triassic in the Nanpanjiang basin. After the obvious drowned event of carbonate platforms in the transitional period between Permian and Triassic, carbonate platforms have evolved into the ramp type from the rimmed shelf type. The differentiation of sedimentary facies becomes clearer in space, which are marked by the changes from an attached platform to a turbidity basin and several isolated platforms in the basin. The striking characteristics are the development of oolitic banks on isolated platforms in Nanning and Jingxi and the reef and bank limestones in the margin of the attached platform in the Early Triassic. Despite the difference of the time span and the architecture of facies succession of third order sedimentary sequences, the process of the third order relative sea level changes reflected by the sedimentary facies succession of the third order sequences is generally synchronous. Therefore, six third order sequences could be discerned in the strata from the Early to the Middle Triassic in the Nanpanjiang basin. Using two types of facies changing surfaces and two types of diachronisms in stratigraphic records as the key elements, the sedimentary facies architectures of the third order sequences that represent sequence stratigraphic frameworks from the Early to the Middle Triassic in the Nanpanjiang basin could be constructed.Mei Mingxiang Ma Yongsheng Deng Jun Gao Jinhan Chen Huijun Meng Qingfen Li Donghai Faculty of Earth Sciences and Resources, China University of Geosciences, Beijing 100083 2003Journal of China University of Geosciences2003,14,2:1
19Effect of intrathymic injection of allogene antigen on immune response to sciatic nerve transplantation in allogenic mice显示文摘BACKGROUND: The latest researches demonstrate that intrathymic injection of MHC antigen which reaches a certain dosage (2 mg, i.e., 4 × 108 cell extraction) can induce immunologic tolerance under non-antilymphocyte serum condition. OBJECTIVE: To investigate the effect of intrathymic injection of allogene antigen on survival and function of sciatic nerve in allogenic mice. DESIGN: Randomized controlled animal study. SETTING: The 4th Affiliated Hosptial of Harbin Medical University. MATERIALS: A total of 32 male donor C57BL/6(H-2b) mice of 4-8 weeks old and weighing 18-22 g and 44 female receptor Balb/c(H-2d) mice of 4-8 weeks old and weighing 18-22 g were selected from Heilongjing Veterinary Institution. The animal experiment had got confirmed consent from local ethic committee. METHODS: The experiment was carried out in the Laboratory (Provincial Key Laboratory) of the Fourth Hospital, Harbin Medical University from June 2006 to May 2007. C57BL/6(H-2b) mice were anesthetized to extract MHC (H-2b) antigen from splenic cells and sciatic nerves. Allogenous nerve transplantation group: Mice were given intrathymic injection of 100 μL saline; two weeks later, frozen sciatic nerves of donor mice were transplanted. Immunosuppressive agent group: Mice were given intrathymic injection of 100 μL saline; two weeks later, fresh sciatic nerves of donor mice were transplanted. At three days before transplantation, 10 mg/kg per day cyclosporin A was intraperitoneally injected once a day till mice were sacrificed. MHC (H-2b) antigen injection group: Mice were given intrathymic injection of MHC (H-2b) antigen from C57BL/6(H-2b) donor mice; two weeks later, fresh sciatic nerves of donor mice were transplanted. Autogenous nerve transplantation group: Mice were given intrathymic injection of 100 μL saline; two weeks later, fresh sciatic nerves were transplanted. MAIN OUTCOME MEASURES: ① Three weeks later, transplanted part of exposured sciatic nerve was used to measure the motor nerve conduction velocity. ② Transplanted nerve was stained with histochemical staining and observed light microscope and electron microscope. ③ Mice received mixed lymphocyte culture and delayed-typed hypersensitiveness to observe absorbency and measure depth of soles. RESULTS: All 76 mice were involved in the final analysis. ① Motor nerve conduction velocity: The nerve recovery in MHC (H-2b) antigen injection group was higher than that in allogenous nerve transplantation group, equal to immunosuppressive agent group and lower than autogenous nerve transplantation group. There were significant differences among them (P < 0.05). ② Histological changes of transplanted nerve: Light and electron microscopes demonstrated that there were a lot of regenerative nerve fibers in autogenous nerve transplantation group, immunosuppressive agent group and MHC (H-2b) antigen injection group, and all nerve fibers passed grafts. ③ Immunological examination: There was no significant difference in mixed lymphocyte culture among allogenous nerve transplantation group, autogenous nerve transplantation group and MHC (H-2b) antigen injection group (P < 0.05). Depth of soles in other groups was deeper than that in the MHC (H-2b) antigen injection group, and there was significant difference (P < 0.05); that was to say, delayed-typed hypersensitiveness was remarkable. CONCLUSION: The intrathymic injection of allogene MHC antigen may induce specific immune tolerance to allogenous sciatic nerve transplantation and promote nerve survival and functional recovery.Yongsheng Ma Guangxiang Hong Qinggang Meng Chenliang Zhou Guibin Qian 2007Neural Regeneration Research2007,2,9:1
20P2 asymmetry of Au's M-band flux and its smoothing effect due to high-Z ablator dopants显示文摘X-ray drive asymmetry is one of the main seeds of low-mode implosion asymmetry that blocks further improvement of the nuclear per-formance of“high-foot”experiments on the National Ignition Facility[Miller et al.,Nucl.Fusion 44,S228(2004)].More particularly,the P2 asymmetry of Au's M-band flux can also severely influence the implosion performance of ignition capsules[Li et al.,Phys.Plasmas 23,072705(2016)].Here we study the smoothing effect of mid-and/or high-Z dopants in ablator on Au's M-band flux asymmetries,by modeling and comparing the implosion processes of a Ge-doped ignition capsule and a Si-doped one driven by X-ray sources with P2 M-band flux asymmetry.As the results,(1)mid-or high-Z dopants absorb hard X-rays(M-band flux)and re-emit isotropically,which helps to smooth the asymmetric M-band flux arriving at the ablation front,therefore reducing the P2 asymmetries of the imploding shell and hot spot;(2)the smoothing effect of Ge-dopant is more remarkable than Si-dopant because its opacity in Au's M-band is higher than the latter's;and(3)placing the doped layer at a larger radius in ablator is more efficient.Applying this effect may not be a main measure to reduce the low-mode implosion asymmetry,but might be of significance in some critical situations such as inertial confinement fusion(ICF)experiments very near the performance cliffs of asymmetric X-ray drives.Yongsheng Li Chuanlei Zhai Guoli Ren Jianfa Gu Wenyi Huo Xujun Meng Wenhua Ye Ke Lan Weiyan Zhang 2017Matter and Radiation at Extremes2017,2,2:1
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