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A fluid flow model in the lacunar-canalicular system under the pressure gradient and electrical field driven loads 被引量:1
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作者 Xiaogang WU Xiyu WANG +8 位作者 Chaoxin LI Zhaowei WANG yuqin sun Yang YAN Yixian QIN Pengcui LI Yanqin WANG Xiaochun WEI Weiyi CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第6期899-916,共18页
The lacunar-canalicular system(LCS)is acknowledged to directly participate in bone tissue remodeling.The fluid flow in the LCS is synergic driven by the pressure gradient and electric field loads due to the electro-me... The lacunar-canalicular system(LCS)is acknowledged to directly participate in bone tissue remodeling.The fluid flow in the LCS is synergic driven by the pressure gradient and electric field loads due to the electro-mechanical properties of bone.In this paper,an idealized annulus Maxwell fluid flow model in bone canaliculus is established,and the analytical solutions of the fluid velocity,the fluid shear stress,and the fluid flow rate are obtained.The results of the fluid flow under pressure gradient driven(PGD),electric field driven(EFD),and pressure-electricity synergic driven(P-ESD)patterns are compared and discussed.The effects of the diameter of canaliculi and osteocyte processes are evaluated.The results show that the P-ESD pattern can combine the regulatory advantages of single PGD and EFD patterns,and the osteocyte process surface can feel a relatively uniform shear stress distribution.As the bone canalicular inner radius increases,the produced shear stress under the PGD or P-ESD pattern increases slightly but changes little under the EFD pattern.The increase in the viscosity makes the flow slow down but does not affect the fluid shear stress(FSS)on the canalicular inner wall and osteocyte process surface.The increase in the high-valent ions does not affect the flow velocity and the flow rate,but the FSS on the canalicular inner wall and osteocyte process surface increases linearly.In this study,the results show that the shear stress sensed by the osteocyte process under the P-ESD pattern can be regulated by changing the pressure gradient and the intensity of electric field,as well as the parameters of the annulus fluid and the canaliculus size,which is helpful for the osteocyte mechanical responses.The established model provides a basis for the study of the mechanisms of electro-mechanical signals stimulating bone tissue(cells)growth. 展开更多
关键词 bone canaliculi osteocyte process pressure gradient ELECTRICITY fluid shear stress(FSS)
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DALP Analysis on Genetic Diversity of <i>Panax notoginseng</i> 被引量:1
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作者 Xiuming Cui Hui Xiao +4 位作者 Jingjing Yang Tina Dong Karl Wah-Keung Tsim yuqin sun Yan Zhu 《Chinese Medicine》 2014年第2期123-129,共7页
Panax notoginseng (Burk) F.H. Chen is one of the most famous Chinese traditional medicinal plants, which belongs to Panax genus under Araliaceae family. At the present, Panax notoginseng cultivated is a mix colony. Us... Panax notoginseng (Burk) F.H. Chen is one of the most famous Chinese traditional medicinal plants, which belongs to Panax genus under Araliaceae family. At the present, Panax notoginseng cultivated is a mix colony. Using DALP makers, this article studied on genetic diversity of cultivated populations of Panax notoginseng in Wenshan County of Yunnan province and Napo country of Guangxi province. And the results showed that there were 260 polymorphic loci detected from the total of 292 in 13 populations, and there was great part of genetic diversity found between populations and the genetic differentiations were lower within populations. So there is broad prospect in good species breeding. And it can provide basic information for resource protection and sustainable use of Panax notoginseng. 展开更多
关键词 PANAX notoginseng GENETIC Diversity DALP
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Sphingosine-1-phosphate,a novel TREM2 ligand,promotes microglial phagocytosis to protect against ischemic brain injury 被引量:8
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作者 Tengfei Xue Juan Ji +7 位作者 yuqin sun Xinxin Huang Zhenyu Cai Jin Yang Wei Guo Ruobing Guo Hong Cheng Xiulan sun 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第4期1885-1898,共14页
The mechanism of sphingosine-1-phosphate(S1P)-mediated phagocytosis remains unknown.Here,we found that S1P or FTY720(an analog of S1P)promoted microglial phagocytosis in stroke independent of S1PRs.First,we used compu... The mechanism of sphingosine-1-phosphate(S1P)-mediated phagocytosis remains unknown.Here,we found that S1P or FTY720(an analog of S1P)promoted microglial phagocytosis in stroke independent of S1PRs.First,we used computer simulation of molecular docking to predict that S1P might be a ligand for triggering receptor expressed on myeloid cells 2(TREM2).Next,microscale thermophoresis(MST),surface plasmon resonance(SPR)and liquid chromatography–tandem mass spectrometry(LC–MS/MS)were performed to reveal that S1P was a novel TREM2 ligand.Then,we confirmed the pro-phagocytosis of S1P targeting in Trem2-Dap12 transfected CHO cells and TREM2 knockdown microglia.Point mutation analysis showed that D104 was the critical binding residue.Trem2^(−/−)mice were used to demonstrate the role of S1P-induced phagocytosis targeting on TREM2 in protecting against ischemic brain injury.Finally,further studies revealed that apolipoprotein E(APOE)loaded with S1P was released by microglia and bound to apoptotic neurons via LDL receptor related protein 1B(LRP1B)and thereby induced microglia to phagocytose apoptotic neurons.Overall,the present work reveals for the first time that S1P acts as a novel endogenous ligand of TREM2 to effectively promote microglial phagocytosis.Our findings provide a new lead compound for developing immunomodulator targeting on TREM2. 展开更多
关键词 S1P TREM2 MICROGLIA PHAGOCYTOSIS Stroke APOE LRP1B Apoptotic neurons
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SEM-CL Study of Quartz Containing Fluid Inclusions in Wangjiazhuang Porphyry Copper (-Molybdenum) Deposit, Western Shandong, China 被引量:5
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作者 Lei Shu Kun Shen +4 位作者 Renchao Yang Yingxin Song yuqin sun Wei Shan Yuxin Xiong 《Journal of Earth Science》 SCIE CAS CSCD 2020年第2期330-341,共12页
The Wangjiazhuang porphyry copper(-molybdenum)deposit is located at Zouping volcanic basin in Shandong Province,East China and hosted in the Wangjiazhuang intrusive complex emplaced along a late volcanic conduit.There... The Wangjiazhuang porphyry copper(-molybdenum)deposit is located at Zouping volcanic basin in Shandong Province,East China and hosted in the Wangjiazhuang intrusive complex emplaced along a late volcanic conduit.There are two types of ores in this deposit:early disseminated and stockwork ores in the ore-bearing intrusion,and late massive sulfide-quartz veins above brecciated quartz monzonite.The ore minerals are mainly pyrite,chalcopyrite,and subordinately magnetite,tennantite,molybdenite with minor bornite,enargite,galena and sphalerite,etc.,and gangue minerals including K-feldspar,biotite,quartz,muscovite-sericite,chlorite and calcite.Combined with fluid inclusion study,the scanning electron microscope-cathodoluminescence(SEM-CL)study of quartz in the deposit and wall rocks shows significant differences between the two types of quartz in the ores.In addition,four types of primary-pseudosecondary fluid inclusions in the quartz have been recognized.They are one-or two-phase aqueous inclusions with vapor/liquid ratios less than 30%to 40%(type Ⅰ);gas-rich inclusions with vapor/liquid ratios more than 50%(type Ⅱ),some of which contain some small opaque minerals,probably chalcopyrite;multiphase fluid inclusions with daughter minerals of halite±anhydrite±opaque(chalcopyrite)±sylvite±hematite±unknown crystal(type Ⅲ);and mica-bearing fluid inclusions(type Ⅳ).Quartz containing abundant muscovite-bearing and halite-bearing fluid inclusions in the mineralized quartz monzonite with potassic-silicic alteration,have better oscillatory growth zoning with CL-colors from bright in the core to darker in the rim,indicating variations of element concentrations in the fluid media from which quartz grew during the later period of magmatic-hydrothermal process.In contrast,the quartz in the sulfide-quartz veins contains mainly fluid inclusions of low-to-medium salinities and does not show oscillatory zoning,indicating that there was less fluctuation in composition and element concentrations of the hydrothermal fluids.However,the quartz containing halite-bearing fluid inclusions and being associated with copper-molybdenum mineralization in the sulfide-quartz veins shows zoning in its rims,indicating variations in composition and element concentrations of the hydrothermal fluids. 展开更多
关键词 Wangjiazhuang copper(-molybdenum)deposit QUARTZ SEM-CL fluid inclusions
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Multi-scale mechanotransduction of the poroelastic signals from osteon to osteocyte in bone tissue 被引量:3
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作者 Xiaogang Wu Chaoxin Li +6 位作者 Kuijun Chen yuqin sun Weilun Yu Meizhen Zhang Yanqin Wang Yixian Qin Weiyi Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2020年第4期964-980,共17页
In order to quantify the poroelastic mechanical signals conduction and evaluate the biomechanical effectiveness of functional units(osteocyte processes,canaliculi and lacuna)in lacunar-canalicular system(LCS),a multis... In order to quantify the poroelastic mechanical signals conduction and evaluate the biomechanical effectiveness of functional units(osteocyte processes,canaliculi and lacuna)in lacunar-canalicular system(LCS),a multiscale poroelastic finite element model was established by using the Comsol Multiphysics software.The poroelastic mechanical signals(pore pressure,fluid velocity,von-Mises stress,strain)were analyzed inside the osteon-osteocyte system.The effects of osteocyte(OCY)’s shape(ellipse and circle),long axis directions(horizontal and vertical)and mechanical properties(Elastic modulus and permeability)on its poroelastic responses were examined.It is found that the OCY processes is the best mechanosensor compared with the OCY body,lacunae and canaliculi.The mechanotransduction ability of the elliptic shaped OCY is stronger than that of circular shaped.The pore pressure and flow velocity around OCYs increase as the elastic modulus and permeability of OCY increase.The established model can be used for studying the mechanism of bone mechanotransduction at the multiscale level. 展开更多
关键词 OSTEOCYTE Lacunar-canalicular system MECHANOTRANSDUCTION Finite element analysis Poroelasticity
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高砷地下水系统中非岩石圈源的沉积物砷异常 被引量:1
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作者 韩龙 孙雨芹 +5 位作者 李曾一 段艳华 韩双宝 张海龙 赵美训 郑焰 《Science Bulletin》 SCIE EI CAS CSCD 2023年第15期1616-1620,M0003,共6页
世界卫生组织认定无机砷为危害全球公众健康的十大化学物质之一.学术界普遍认为地下水中无机砷源自地层,非人为污染所致,从基岩或经风化搬运形成的松散沉积物含水层中释放进入地下水,但鲜见岩石圈砷异常的报道.本研究对银川平原高砷地... 世界卫生组织认定无机砷为危害全球公众健康的十大化学物质之一.学术界普遍认为地下水中无机砷源自地层,非人为污染所致,从基岩或经风化搬运形成的松散沉积物含水层中释放进入地下水,但鲜见岩石圈砷异常的报道.本研究对银川平原高砷地下水系统中沉积物的物源和砷源开展了定量溯源,构建了基于粒度、无机化学参数(Fe/Al和Si/Al比)及有机碳-13和碳-14的无机物源、有机物源及砷源端元模型,发现沉积物中存在贺兰山和黄河等岩石圈源之外的“过量砷”;结合环青藏高原多个高砷地下水区文献数据分析,发现可通过As/Fe摩尔比大于0.0003识别沉积物砷异常.鉴于砷在地表-地下水交互界面的氧化次生富集,提出该异常源自水圈,可循环进入地下水“再生”.这可解释全球高砷地下水冲洪积平原上游地区无显著岩石圈砷异常之谜. 展开更多
关键词 高砷地下水 松散沉积物 岩石圈 次生富集 化学物质 银川平原 冲洪积平原 交互界面
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The effects of the source composition on the origin of orthopyroxenebearing adakitic granitoid in West Qinling,Central China 被引量:1
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作者 Yuanhui Xie Xiaowei Li +3 位作者 Xuanxue Mo Guochen Dong yuqin sun Wei Shan 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第3期180-200,共21页
Orthopyroxene-bearing granodiorite(sometimes referred to as‘charnockite’)with an adakitic affinity is a rare type of granitoid.It is generally accepted that the stabilization of orthopyroxene in igneous charnockites... Orthopyroxene-bearing granodiorite(sometimes referred to as‘charnockite’)with an adakitic affinity is a rare type of granitoid.It is generally accepted that the stabilization of orthopyroxene in igneous charnockites essentially requires low aH_(2)O and/or high temperatures in a closed system.However,orthopyroxene can be an antecryst in a trans-crustal magmatic system.In this regard,orthopyroxenebearing granitoids are somewhat analogous to pseudo-charnockites,where the orthopyroxene stems from a mafic reservoir.On the other hand,the source compositions of continental adakites can vary,which is often ignored in the interpretation of their contribution to the adakitic geochemical signature.In this study,we have investigated a rare orthopyroxene-bearing felsic pluton from the Zhuyuan area of West Qinling,Central China.The Zhuyuan pluton was emplaced in the Middle–Late Triassic(222–217 Ma)and is mainly composed of metaluminous to weakly peraluminous granodiorites belonging to the high-K calc-alkaline series.Moreover,they are characterized by high Mg#values(49.7–60.9)and Sr contents(471–697 ppm),low Y(12.2–15.4 ppm)and Yb(1.03–1.24 ppm)contents,high Sr/Y(33.2–46.2)and(La/Yb)_(N)(15.3–21.4)ratios,and weakly negative Eu anomalies(Eu/Eu^(*)=0.78–0.89).The Zhuyuan adakitic granodiorites exhibit fairly limited Sr–Nd–Pb isotopic ratios and variable zircon initial Hf isotopes,indicating a major contribution from the Neoproterozoic basement of the Qinling Orogenic Belt.There is no evidence of any formation through high-pressure magmatic processes,and we propose that the adakitic signature of the Zhuyuan pluton could have been inherited from its source rocks(i.e.,from the Neoproterozoic basement).The orthopyroxenes in the Zhuyuan granodiorites display poikilitic textures with high MgO,NiO and Cr_(2)O_(3) contents,indicating that they have an antecrystic origin.Studies of regional tectonic evolution have shown that the Zhuyuan granodiorites formed during the tearing stage of the A’nimaque–Mianlue oceanic subduction slab.Therefore,this study emphasizes the effect of source inheritance on the formation of pseudo-charnockite with an adakitic signature. 展开更多
关键词 Qinling Orogenic Belt Adakitic rock Orthopyroxene-bearing granodiorite Pseudo-charnockite
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Biomechanical evaluation of two fusion techniques based on finite element analysis:Percutaneous endoscopic and minimally invasive transforaminal lumbar interbody fusion 被引量:1
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作者 Yang Yan Jiarui Li +7 位作者 Jianhao Yu Yan Wang Hao Dong yuqin sun Xiaogang Wu Liming He Weiyi Chen Haoyu Feng 《Medicine in Novel Technology and Devices》 2022年第4期17-25,共9页
As a novel minimally invasive technique,percutaneous endoscopic transforaminal lumbar interbody fusion(PETLIF)has been widely used in the treatment of lumbar degenerative diseases.The purpose of this study was to anal... As a novel minimally invasive technique,percutaneous endoscopic transforaminal lumbar interbody fusion(PETLIF)has been widely used in the treatment of lumbar degenerative diseases.The purpose of this study was to analyze these two operation types’biomechanical performances of PE-TLIF and traditional minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF)using the finite element(FE)method.The intact FE models of L4-L5 were established and validated based on the CT images.On this basis,the FE models of MIS-TLIF and PETLIF were established and analyzed.It is demonstrated that for lumbar interbody fusion with the oblique asymmetrically implanted cage under bilateral pedicle screws and rods fixation,such as MIS-TLIF and PE-TLIF,different degrees of articular process resection have no significant effect on the cage subsidence,and the surgical segment can achieve similar stability.In addition,the maximum stress of the L4 inferior endplate of MIS-TLIF and PE-TLIF is greater than that of the L5 superior endplate,which indicates that MIS-TLIF and PE-TLIF can cause cage subsidence in the L4 inferior endplate. 展开更多
关键词 Percutaneous endoscopic transforaminal lumbar interbody fusion Minimally invasive surgery Degenerative lumbar diseases Finite element analysis BIOMECHANICS
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