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Crystal structures and biochemical studies of human lysophosphatidic acid phosphatase type 6

Protein & Cell 2013年第7期4卷 548-561页

作者： Jun Li Yu Dong Xingru Lü Lu Wang Wei Peng Xuejun C.Zhang Zihe Rao National laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Structure Biology laboratory Tsinghua UniversityBeijing 100084China Tianjin Key laboratory of Protein Science College of Life SciencesNankai UniversityTianjin 300071China

Lysophosphatidic acid(LPA)is an important bioac-tive phospholipid involved in cell signaling through G-protein-coupled receptors *** is also involved in balancing the lipid composition inside the cell,and modulates the function of lipid rafts as an intermediate in phospholipid *** of its involvement in these important processes,LPA degradation needs to be regulated as precisely as its ***-tidic acid phosphatase type 6(ACP6)is an LPA-specifi c acid phosphatase that hydrolyzes LPA to monoacylglyc-erol(MAG)and ***,we report three crystal structures of human ACP6 in complex with malonate,L-(+)-tartrate and tris,*** analyses revealed that ACP6 possesses a highly conserved Rossmann-fold-like body domain as well as a less conserved cap *** vast hydrophobic substrate-binding pocket,which is located between those two domains,is suitable for ac-commodating LPA,and its shape is different from that of other histidine acid phosphatases,a fact that is consistent with the observed difference in substrate *** analysis of the binding of three molecules in the active site reveals the involvement of six conserved and crucial residues in binding of the LPA phosphate group and its *** structure also indicates a water-supplying channel for substrate *** structural data are consistent with the fact that the enzyme is active as a *** combination with additional mutagenesis and enzyme activity studies,our structural data provide important insights into substrate recognition and the mechanism for catalytic activity of ACP6.

关键词： lysophosphatidic acid histidine acid phos-phatase crystal structure

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Sedimentary features and sequence stratigraphy of the successions around the Carboniferous-Permian boundary in the Ordos Basin:links to glacial and volcanic impacts

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Journal of Palaeogeography 2023年第3期12卷 358-383页

作者： Zhong-Shuai Hou Shi-Yue Chen Zhao Liang Hebei Key laboratory of Strategic Critical Mineral Resources Hebei GEO UniversityShijiazhuang 050031China Interdisciplinary Science Research Institute Hebei GEO UniversityShijiazhuang 050031China School of Geosciences China University of PetroleumQingdao 266580China

The sedimentary successions around the Carboniferous-Permian boundary(CPB)in the Ordos Basin were investigated using extensive outcrop,borehole,well logging,thin section,and geochemistry data to study sedimentary and sequence stratigraphic responses to glaciation and volcanism in paleotropical transitional *** the studied interval,five distinct lithofacies have been identified,including bauxite,coal,and carbonaceous shale(No.8+9 coal seams),sandstone(Qiaotou),limestone(Baode),and mudstone,which can be classified into three lithofacies *** most complete lithofacies associ-ation is composed of bauxite,coal,carbonaceous shale,sandstone,limestone/mudstone or their combinations from the bottom to the top,while coal and carbonaceous shale,as well as sandstone,are absent locally,resulting in the formation of the other two types of lithofacies *** occurrence of bauxite in-dicates shelf exposure and weathering,the occurrence of coal and carbonaceous shale indicates swampiness of the shelf,and the occurrence of sandstone reveals river rejuvenation;all of these are thought to be sedimentary responses to the transcontinental glacier expansion in Gondwana around the *** presence of limestone and mudstone indicates carbonate platform and lagoon deposition,respectively,in the context of the earliest Asselian transgression caused by volcanism-induced glacier *** lithofacies associations record the regressive-transgressive cycles that occurred because of glaciation and volcanism near the *** top surface of bauxite can be used as a sequence boundary,while the lowstand systems tract consists of the No.8+9 coal seams and the Qiaotou sandstone,and the transgressive systems tract consists of the overlying Baode limestone and laterally equivalent *** lowstand systems tract,which contains source rock and hydrocarbon reservoirs,and the overlying transgressive systems tract,which serves as cap rock,form an excellent source-reservoi

关键词： Glaciation Volcanism Incised valley Sequence stratigraphy Ordos basin

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Fluidization of binary mixtures of sisal residue and sand:A new model for deriving the final fluidization velocity

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Particuology 2018年第5期16卷 10-22页

作者： David Vasconcelos Gabriele Batalha Luis Gabriel Pereira Carlos Augusto Pires Chemical Reaction Engineering laboratory Federal University of Bahia40.210-910SalvadorBABrazil

The influence of different factors on the fiuidization of a binary mixture of sisal residue and sand was *** particle sizes of the sand and sisal residue were varied from 0.2to 0.8mm and the biomass mass fractions from 2% to 9%.Some segregation was noted,and a significant relationship was found among the final fluidization velocity (Uff),the biomass and sand sizes,and the biomass mass fraction.A novel model was developed for predicting Uff,leading to an average discrepancy of 12.69% between the measured and predicted Uff compared with the best match of 15.32% when using a model from a previous *** new model was applied to data from studies using other biomass and a broad range of particle *** average divergences from measured values when using the new model were 7.9% for corn cob and walnut shell,and 20.5% for sweet sorghum bagasse,tobacco residue, and soy *** were superior to the values derived using other *** results confirm the accuracy of the model developed in this work and show that it represents a viable alternative way to calculate Uff for a binary mixture of sand and biomass.

关键词： Fluidization Binary mixture Sisal residue Final fluidization velocity model

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Effects of riverbed scour on seismic performance of high-rise pile cap foundation

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 533-543页

作者： Han Zhenfeng Ye Aijun Fan Lichu State Key laboratory for Disaster Reduction of Civil Engineering Tongji University Shanghai 200092 China

To explore the seismic performance of a high-rise pile cap foundation with riverbed scour, a finite element model for foundations is introduced in the OpenSees finite element framework. In the model, a fiber element is used to simulate the pile shaft, a nonlinear p-y element is used to simulate the soil-pile interaction, and the p-factor method is used to reflect the group effects. A global and local scour model is proposed, in which two parameters, the scour depth of the same row of piles and the difference in the scour depth of the upstream pile and the downstream pile, are included to study the influence of scour on the foundation. Several elasto-plastic static pushover analyses are performed on this finite element model. The analysis results indicate that the seismic capacity （or supply） of the foundation is in the worst condition when the predicted deepest global scout depth is reached, and the capacity becomes larger when the local scour depth is below the predicted deepest global scout depth. Therefore, to evaluate the seismic capacity of a foundation, only the predicted deepest global scout depth should be considered. The method used in this paper can be also applied to foundations with other soil types.

关键词： riverbed scour high-rise pile cap pile group fiber element seismic capacity pushover p-y element

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CD301b^(+) macrophages mediate angiogenesis of calcium phosphate bioceramics by CaN/NFATc1/VEGF axis

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Bioactive Materials 2022年第9期7卷 446-455页

作者： Jiaolong Wang Qin Zhao Liangliang Fu Shihang Zheng Can Wang Litian Han Zijian Gong Ziming Wang Hua Tang Yufeng Zhang The State Key laboratory Breeding Base of Basic Science of Stomatology(Hubei-MOST)and Key laboratory of Oral Biomedicine Ministry of EducationSchool&Hospital of StomatologyWuhan UniversityWuhan430079HubeiPR China Institute of Infection and Immunity Science and Technology Innovation CenterShandong First Medical University&Shandong Academy of Medical SciencesJinan250000ShandongPR China Medical Research Institute School of MedicineWuhan UniversityWuhan430071HubeiPR China

Calcium phosphate(cap)bioceramics are important for tissue regeneration and immune response,yet how cap bioceramics influence these biological processes remains ***,the role of immune cells in biomaterial-mediated regeneration,especially macrophages,has been well ***301b^(+)macrophages were a new subset of macrophages we have discovered,which were required for bioceramics-mediated bone ***,the impact of CD301b^(+)macrophages on angiogenesis,which is a vital prerequisite to bone formation is yet ***,we found that CD301b^(+)macrophages were closely correlated to angiogenesis of cap ***,depletion of CD301b^(+)macrophages led to the failure of *** showed that store-operated Ca^(2+)entry and calcineurin signals regulated the VEGF expression of CD301b^(+)macrophages via the NFATc1/VEGF *** of calcineurin effectively impaired angiogenesis via decreasing the infiltration of CD301b^(+)*** findings provided a potential immunomodulatory strategy to optimize the integration of angiogenesis and bone tissue engineering scaffold materials.

关键词： Calcium phosphate ceramics Macrophage Angiogenesis CD301b Calcineurin

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Ediacaran integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 7-24页

作者： Chuanming ZHOU Xunlai YUAN Shuhai XIAO Zhe CHEN Hong HUA CAS Key laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Palaeoenvironment Chinese Academy of Sciences State Key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Palaeoenvironment Chinese Academy of Sciences Department of Geosciences Virginia Tech Blacksburg State Key laboratory of Continental Dynamics Department of Geology Northwest University

Ediacaran successions occur widely in various depositional facies in South China and yield a series of fossil Lagerst?tten, providing a complete fossil record for the evolution of marine ecosystems after the terminal Cryogenian global glaciation. Carbonate-dominated Ediacaran successions in shallow water facies in South China record a nearly complete δ^(13)C profile that may reflect variations of marine carbon isotopic composition during the Ediacaran Period. The Ediacaran fossils andδ^(13)C profiles from South China permit stratigraphic correlation and subdivision of the Ediacaran strata. Based on biostratigraphic, chemostratigraphic, and geochronometric data from the Ediacaran successions in South China, we propose that the Ediacaran System in China can be subdivided into two series, with three stages in each series. The lower series is characterized by acanthomorphic acritarchs and the upper series by Ediacara-type macrofossils, and the two series are separated by the declining limb of a pronounced δ^(13)C negative excursion(EN3) in the upper Doushantuo Formation. The basal boundary of Stage1 is the same as the basal boundary of Ediacaran System, which has been defined at the base of the cap carbonate unit. Stage 2 represents the first radiation of Ediacaran microscopic organisms, with δ^(13)C feature representing by positive values(EP1). The base of the Stage 2 is placed at the first appearance level of a spiny acritarch species. Stage 3 is characterized by the occurrence of more diverse acritarchs and δ^(13)C feature EP2, with its basal boundary defined by a δ^(13)C negative excursion(EN2) occurring in the middle Doushantuo Formation. The basal boundary of Stage 4 is the same as the upper series. Stage 5 is marked by the occurrence of macrfossils of Miaohe biota, and its lower boundary can be placed at the level where δ^(13)C values transition from positive to negative in MNE, or the first appearance level of macrofossils of the Miaohe biota. Stage 6 is charact

关键词： Ediacaran Biostratigraphy Chemostratigraphy Stratotype section South China

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Trueness investigation of routine creatinine assays on nine homogeneous systems in Beijing demonstrates an encouraging outcome that meets clinical requirements

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Chinese Medical Journal 2010年第17期123卷 2364-2369页

作者： LIU Yan XU Guo-bin Department of Clinical laboratory Peking University First Hospital Beijing 100034 China

Background Serum creatinine （Scr） measurement plays a key role in glomerular filtration rate estimation （eGFR）,chronic kidney disease （CKD） diagnosis as well as CKD treatment. However, the test results of Scr from different laboratories vary significantly. In order to get comparable results, the European in vitro diagnostic （IVD） directive requires traceability to reference methods and materials. The purpose of this study was to verify the effect of traceability implementation by investigating the trueness of creatinine measurement on nine homogenous systems in Beijing. Methods Commutable frozen human serum reference material, National Institute of Standards ＆ Technology （NIST） Standard Reference Material （SRM） 967, was used to verify the trueness of Scr measurement results from nine homogeneous analytical systems of seven companies which are the most widely used systems in Beijing＇s third-grade hospitals. The methods referred to the Jaffe＇s and Enzymatic methods. Results from nine routine measurement systems were assessed using two criteria： biological variability and Clinical laboratory Improvement Amendments＇ 88 （CLIA＇ 88）.We simulated a series of broken lines representing the limits of SD and bias that would produce a relative increase （or decrease） of 10% and 20% in the measurement error when estimating GFR （MEeGFR） using the isotope dilution mass spectrometry （IDMS）-traceable Modification of Diet in Renal Disease （MDRD） Study equation. Results of the College of American Pathologists （cap） 2008-B LN24 Survey were compared with our investigation results. Results Compared with the total error criteria of biological variability, Ortho （traceable to IDMS） met the minimum acceptable criteria; Roche （Jaffe）, Roche （Enzymatic）, Shino and Daiichi met the desirable criteria at level Ⅰ. At level Ⅱ, Ortho （traceable to gas chromatography/isotope dilution mass spectrometry, GC/IDMS）, Dade Behring and Beckman （traceable to rate Jaffe） met the minimum acceptable criteria; Ro

关键词： creatinine glomerular filtration rate standardization

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Settling and spreading behaviour of particle clusters in quiescent liquids in confined vessels

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Particuology 2023年第12期83卷 91-100页

作者： Sayan Pal Amol A.Kulkarni Chemical Engineering&Process Development Division CSIR-National Chemical LaboratoryPune411008India Academy of Scientific and Innovative Research(AcSIR) Ghaziabad 201002India University College London Torrington PlaceLondonWC1E 7JEUK

Here we report experiments on particle cluster settling at high Reynolds number in quiescent liquid contained in a *** particles were observed to spread at the vessel bottom surface in a near-circular annular shape after settling irrespective of the shape of the vessel cross-section and particle shape,size,and *** of different parameters such as mass,type and aspect ratio of the particles,height,and viscosity of liquid was investigated on spreading *** of the hemispherical bottom cap of the cluster that bounces upon hitting the vessel bottom surface was found to be responsible for the final circular annular shape of the settled *** leakage from the cluster was seen in the form of a *** the liquid having viscosity beyond 100 cP,cluster breakage was observed that resulted in hindered settling and asymmetric shapes of finally settled *** observations are useful to understand the overall area over which settling and spreading of such clusters can be observed.

关键词： Particle cluster Temporal evolution Settling Spreading

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Demonstration of a low‐complexity memory‐polynomial‐aided neural network equalizer for cap visible‐light communication with superluminescent diode

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Opto-Electronic Advances 2020年第8期3卷 1-11页

作者： Fangchen Hu Jorge A.Holguin-Lerma Yuan Mao Peng Zou Chao Shen Tien Khee Ng Boon S.Ooi Nan Chi Key laboratory for Information Science of Electromagnetic Waves(MoE) Fudan UniversityShanghai 200433China Photonics laboratory King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Visible-light communication(VLC)stands as a promising component of the future communication network by providing high-capacity,low-latency,and high-security wireless *** diode(SLD)is proposed as a new light emitter in the VLC system due to its properties of droop-free emission,high optical power density,and low *** this paper,we analyze a VLC system based on SLD,demonstrating effective implementation of carrierless amplitude and phase modulation(cap).We create a low-complexity memory-polynomial-aided neural network(MPANN)to replace the traditional finite impulse response(FIR)post-equalization filters of cap,leading to significant mitigation of the linear and nonlinear distortion of the VLC *** MPANN shows a gain in Q factor of up to 2.7 dB higher than other equalizers,and more than four times lower complexity than a standard deep neural network(DNN),hence,the proposed MPANN opens a pathway for the next generation of robust and efficient neural network equalizers in *** experimentally demonstrate a proof-of-concept 2.95-Gbit/s transmission using MPANN-aided cap with 16-quadrature amplitude modulation(16-QAM)through a 30-cm channel based on the 442-nm blue SLD emitter.

关键词： superluminescent diode visible-light communication neural network

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Highly efficient and stable coupling of kilowatt-level continuous wave laser into hollow-core fibers

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Chinese Optics Letters 2022年第4期20卷 6-10页

作者：崔宇龙黄威周智越李昊王蒙陈子伦王泽锋 College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China State Key laboratory of Pulsed Power Laser Technology Changsha 410073China Hunan Provincial Key laboratory of High Energy Laser Technology Changsha 410073China

Fiber gas lasers based on gas-filled hollow-core fibers(HCFs)perfectly combine the advantages of fiber lasers and gas lasers and have obtained fast development in the past ***,stable and efficient coupling of high-power pump lasers into the HCFs is one of the key problems to be *** this paper,we study the coupling of high-power continuous wave fiber lasers into anti-resonant HCFs through an *** optimizing the splicing parameters,a maximum laser power of 1167 W was injected into the 1-m-long HCFs,and 1021W was obtained at the output end,giving a total transmission efficiency of〜87.5%.A more than 1 h test showed the stability of such a coupling ***,the laser beam quality was well *** work opens new opportunities for stable and highly efficient coupling of high-power lasers into HCFs,which is significant for its applications in many other fields besides high-power fiber gas lasers,such as high-power laser delivering.

关键词： hollow-core fibers end-caps high power coupling methods

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