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1Effects of resource additions on species richness and ANPP in an alpine meadow community显示文摘Aims Theories based on resource additions indicate that plant species richness is mainly determined by the number of limiting resources.However,the individual effects of various limiting resources on species richness and aboveground net primary productivity(ANPP)are less well understood.Here,we analyzed potential linkages between additions of limiting resources,species loss and ANPP increase and further explored the underlying mechanisms.Methods Resources(N,P,K and water)were added in a completely randomized block design to alpine meadow plots in the Qinghai-Tibetan Plateau.Plant aboveground biomass,species composition,mean plant height and light availability were measured in each plot.Regression and analysis of variance were used to analyze the responses of these measures to the different resource-addition treatments.Important Findings Species richness decreased with increasing number of added limiting resources,suggesting that plant diversity was apparently determined by the number of limiting resources.Nitrogen was the most important limiting resource affecting species richness,whereas Pand K alone had negligible effects.The largest reduction in species richness occurred when all three elements were added in combination.Water played a different role compared with the other limiting resources.Species richness increased when water was added to the treatments with N and P or with N,P and K.The decreases in species richness after resource additions were paralleled by increases in ANPP and decreases in light penetration into the plant canopy,suggesting that increased light competitionwas responsible for the negative effects of resource additions on plant species richness.Zhengwei Ren Qi Li Chengjin Chu Luqiang Zhao Jieqi Zhang Dexiecuo Ai Yingbo Yang Gang Wang 2010Journal of Plant Ecology2010,3,1:40
2Simulation of the Earth' s gravitational field recovery from GRACE using the energy balance approach显示文摘Based on the measurement principles of GRACE satellites, the observation equations are set up using the energy balance approach. The Earth's gravitational field complete up to degree and order 120 is recovered applying the preconditioning conjugate gradient iterative approach by numerical simulation. Assuming an accuracy of 1?m/s in range-rate measurements of the K-band microwave ranging system, the matching relationships of accuracies of K-band microwave ranging system, SuperSTAR Accelerometer, position vector and velocity vector measurements are investigated.ZHENGWei LUXiaolet HSUHoutse SHAOChenggang LUOJun WANGNengchao 2005Progress in Natural Science:Materials International2005,15,7:28
3Wnt/β-catenin signalling:function,biological mechanisms,and therapeutic opportunities显示文摘The Wnt/β-catenin pathway comprises a family of proteins that play critical roles in embryonic development and adult tissue homeostasis.The deregulation of Wnt/β-catenin signalling often leads to various serious diseases,including cancer and non-cancer diseases.Although many articles have reviewed Wnt/β-catenin from various aspects,a systematic review encompassing the origin,composition,function,and clinical trials of the Wnt/β-catenin signalling pathway in tumour and diseases is lacking.In this article,we comprehensively review the Wnt/β-catenin pathway from the above five aspects in combination with the latest research.Finally,we propose challenges and opportunities for the development of small-molecular compounds targeting the Wnt signalling pathway in disease treatment.Jiaqi Liu Qing Xiao Jiani Xiao Chenxi Niu Yuanyuan Li Xiaojun Zhang Zhengwei Zhou Guang Shu Gang Yin 2022Signal Transduction and Targeted Therapy2022,7,2:28
4Biomechanical effects of bone cement volume on the endplates of augmented vertebral body: a three-dimensional finite element analysis显示文摘Yan Liang Chang Zhen Xu Zhengwei Liu Tuanjiang He Baorong Hao Dingjun 2014Chinese Medical Journal2014,,1:23
5Review of the characteristics and graded utilisation of coal gasification slag显示文摘The characteristics of the energy structure of rich coal,less oil and less gas,coupling with a high external dependence on oil and natural gas and the emphasis on the efficient and clean utilisation of coal,have brought opportunities for coal chemical industry.However,with the large-scale popularisation of coal gasification technology,the production and resulting storage of coal gasification slag continue to increase,which not only result in serious environmental pollution and a waste of terrestrial resources,but also seriously affect the sustainable development of coal chemical enterprises.Hence,the treatment of coal gasification slag is extremely important.In this paper,the production,composition,morphology,particle size structure and water holding characteristics of coal gasification slag are introduced,and the methods of carbon ash separation of gasification slag,both domestically and abroad,are summarised.In addition,the paper also summarises the research progress on gasification slag in building materials,ecological restoration,residual carbon utilisation and other high-value utilisation,and ultimately puts forward the idea of the comprehensive utilisation of gasification slag.For large-scale consumption to solve the environmental problems of enterprises and achieve high-value utilisation to increase the economic benefits of enterprises,it is urgent to zealously design a reasonable and comprehensive utilisation technologies with simple operational processes,strong adaptability and economic benefits.Xiaodong Liu Zhengwei Jin Yunhuan Jing Panpan Fan Zhili Qi Weiren Bao Jiancheng Wang Xiaohui Yan Peng Lv Lianping Dong 2021Chinese Journal of Chemical Engineering2021,34,7:21
6Identification and fine mapping of quantitative trait loci for seed vigor in germination and seedling establishment in rice显示文摘Seed vigor is an index of seed quality that is used to describe the rapid and uniform germination and the establishment of strong seedlings in any environmental conditions.Strong seed vigor in low-temperature germination conditions is particularly important in direct-sowing rice production systems. However, seed vigor has not been selected as an important breeding trait in traditional breeding programs due to its quantitative inherence. In this study, we identified and mapped eight quantitative trait loci(QTLs) for seed vigor by using a recombinant inbred population from a cross between rice(Oryza sativa L. ssp. indica) cultivars ZS97 and MH63.Conditional QTL analysis identified qSV-1, qSV-5b, qSV-6a, qSV-6b, and qSV-11 influenced seedling establishment and that qSV-5a, qSV-5c, and qSV-8 influenced only germination. Of these,qSV-1, qSV-5b, qSV-6a, qSV-6b, and qSV-8 were low-temperature-specific QTLs. Two major-effective QTLs, qSV-1, and qSV-5c were narrowed down to 1.13-Mbp and 400-kbp genomic regions, respectively. The results provide tightly linked DNA markers for the marker-assistant pyramiding of multiple positive alleles for increased seed vigor in both normal and low-temperature germination environments.Lixia Xie Zhengwei Tan Yuan Zhou Rongbao Xu Laibao Feng Yongzhong Xing Xiaoquan Qi 2014Journal of Integrative Plant Biology2014,56,8:17
7Comparison of the toxicity of silver nanoparticles and silver ions on the growth of terrestrial plant model Arabidopsis thaliana显示文摘Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials, but the mechanism of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and Ag+ on Arabidopsis thaliana at the physiological, ultrastructural and molecular levels. AgNPs did not affect seed germination; however, they showed stronger inhibitory effect on root elongation than Ag+ . The results of transmission electron microscopy and metal content analysis showed that AgNPs could be accumulated in leaves. These absorbed AgNPs disrupted the thylakoid membrane structure and decreased chlorophyll content, which can inhibit plant growth. By comparison, a small amount of Ag+ was absorbed by seedlings, and it did not pronouncedly affect chloroplast structure and other metal ion absorption as AgNPs did. Compared with Ag+ , AgNPs could alter the transcription of antioxidant and aquaporin genes, indicating that AgNPs changed the balance between the oxidant and antioxidant systems, and also affected the homeostasis of water and other small molecules within the plant body. All the data from physiological, ultrastructural and molecular levels suggest that AgNPs were more toxic than Ag+ .Haifeng Qian Xiaofeng Peng Xiao Han Jie Ren Liwei Sun Zhengwei Fu 2013Journal of Environmental Sciences2013,25,9:14
8Effect of Protein Kinase C on Proliferation and Apoptosis of T Lymphocytes in Idiopathic Thrombocytopenic Purpura Children显示文摘It is well-documented that T lymphocyte proliferation and apoptosis are abnormal in idiopathic thrombocytopenic purpura (ITP) children. However, the underlying regulation mechanisms especially in terms of signal transduction remain unknown. In this paper, we reported the changes of protein kinase C (PKC) activity in peripheral blood T lymphocytes and the effect of PKC on T lymphocyte proliferation and apoptosis. We demonstrated that in ITP children, the activator (PMA) and inhibitor (H-7) of PKC affected on T lymphocyte proliferation and apoptosis dramatically, but they altered little in healthy children. PKC activity was significantly enhanced in ITP children together with an increased expression of FasL on CD3+ T, CD4+ T and CD8+T cells, resulting in a positive correlation between PKC activity and the expression of FasL on T cells. While the PKC activity and the platelet count were negatively correlated. Taken together, our findings suggest that the PKC activation may enhance T lymphocytes activity, suppress T cell apoptosis and be involve in thrombocytes damage as a mechanism related to immune pathogenesis of ITP.Changlin Wu~(1,2) Fang Liu~1 Xuemin Zhou~1 Zhengwei Cheng~1 Xiaomeng Yang~1 Hong Xiao~1 Qun Chen~1 Kangrong Cai~1 ~1Department of Microbiology and Immunology,Guangdong Medical College,Zhanjiang,Guangdong,524023,China ~2Corresponding to:Dr.Changlin Wu,Department of Microbiology and Immunology,Guangdong Medical College,2 Wen-Ming East Road,Zhanjiang,Guangdong,524023,China. 2005Cellular & Molecular Immunology2005,2,3:12
9Insight-HXMT observations of the first binary neutron star merger GW170817显示文摘Finding the electromagnetic(EM) counterpart of binary compact star merger, especially the binary neutron star(BNS) merger,is critically important for gravitational wave(GW) astronomy, cosmology and fundamental physics. On Aug. 17, 2017,Advanced LIGO and Fermi/GBM independently triggered the first BNS merger, GW170817, and its high energy EM counterpart,GRB 170817 A, respectively, resulting in a global observation campaign covering gamma-ray, X-ray, UV, optical, IR, radio as well as neutrinos. The High Energy X-ray telescope(HE) onboard Insight-HXMT(Hard X-ray Modulation Telescope) is the unique high-energy gamma-ray telescope that monitored the entire GW localization area and especially the optical counterpart(SSS17 a/AT2017 gfo) with very large collection area(~1000 cm^2) and microsecond time resolution in 0.2-5 MeV. In addition,Insight-HXMT quickly implemented a Target of Opportunity(ToO) observation to scan the GW localization area for potential X-ray emission from the GW source. Although Insight-HXMT did not detect any significant high energy(0.2-5 MeV) radiation from GW170817, its observation helped to confirm the unexpected weak and soft nature of GRB 170817 A. Meanwhile,Insight-HXMT/HE provides one of the most stringent constraints(~10^(-7) to 10^(-6) erg/cm^2/s) for both GRB170817 A and any other possible precursor or extended emissions in 0.2-5 MeV, which help us to better understand the properties of EM radiation from this BNS merger. Therefore the observation of Insight-HXMT constitutes an important chapter in the full context of multi-wavelength and multi-messenger observation of this historical GW event.TiPei Li ShaoLin Xiong ShuangNan Zhang FangJun Lu LiMing Song XueLei Cao Zhi Chang Gang Chen Li Chen TianXiang Chen Yong Chen YiBao Chen YuPeng Chen Wei Cui WeiWei Cui JingKang Deng YongWei Dong YuanYuan Du MinXue Fu GuanHua Gao He Gao Min Gao MingYu Ge YuDong Gu Ju Guan ChengCheng Guo DaWei Han Wei Hu Yue Huang Jia Huo ShuMei Jia LuHua Jiang WeiChun Jiang Jing Jin YongJie Jin Bing Li ChengKui Li Gang Li MaoShun Li Wei Li Xian Li XiaoBo Li XuFang Li YanGuo Li ZiJian Li ZhengWei Li XiaoHua Liang JinYuan Liao CongZhan Liu GuoQing Liu HongWei Liu ShaoZhen Liu XiaoJing Liu Yuan Liu YiNong Liu Bo Lu XueFeng Lu Tao Luo Xiang Ma Bin Meng Yi Nang JianYin Nie Ge OU JinLu Qu Na Sai Liang Sun Yin Tan Lian Tao WenHui Tao YouLi Tuo GuoFeng Wang HuanYu Wang Juan Wang WenShuai Wang YuSa Wang XiangYang Wen BoBing WU Mei Wu GuangCheng Xiao He Xu YuPeng Xu LinLi Yan JiaWei Yang Sheng Yang YanJi Yang AiMei Zhang ChunLei Zhang ChengMo Zhang Fan Zhang HongMei Zhang Juan Zhang Qiang Zhang Shu Zhang Tong Zhang Wei Zhang WanChang Zhang WenZhao Zhang Yi Zhang Yue Zhang YiFei Zhang YongJie Zhang Zhao Zhang ZiLiang Zhang HaiSheng Zhao JianLing Zhao XiaoFan Zhao ShiJie Zheng Yue Zhu YuXuan Zhu ChangLin Zou 2018Science China(Physics,Mechanics & Astronomy)2018,61,3:12
10Recent Progress in Dual-Polarization Radar Research and Applications in China显示文摘Dual-polarization(dual-pol)radar can measure additional parameters that provide more microphysical information of precipitation systems than those provided by conventional Doppler radar.The dual-pol parameters have been successfully utilized to investigate precipitation microphysics and improve radar quantitative precipitation estimation(QPE).The recent progress in dual-pol radar research and applications in China is summarized in four aspects.Firstly,the characteristics of several representative dual-pol radars are reviewed.Various approaches have been developed for radar data quality control,including calibration,attenuation correction,calculation of specific differential phase shift,and identification and removal of non-meteorological echoes.Using dual-pol radar measurements,the microphysical characteristics derived from raindrop size distribution retrieval,hydrometeor classification,and QPE is better understood in China.The limited number of studies in China that have sought to use dual-pol radar data to validate the microphysical parameterization and initialization of numerical models and assimilate dual-pol data into numerical models are summarized.The challenges of applying dual-pol data in numerical models and emerging technologies that may make significant impacts on the field of radar meteorology are discussed.Kun ZHAO Hao HUANG Mingjun WANG Wen-Chau LEE Gang CHEN Long WEN Jing WEN Guifu ZHANG Ming XUE Zhengwei YANG Liping LIU Chong WU Zhiqun HU Sheng CHEN 2019Advances in Atmospheric Sciences2019,36,9:12
11The enhanced X-ray Timing and Polarimetry mission—eXTP显示文摘In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources.The paper provides a detailed description of:(1) the technological and technical aspects, and the expected performance of the instruments of the scientific payload;(2) the elements and functions of the mission, from the spacecraft to the ground segment.ShuangNan Zhang Andrea Santangelo Marco Feroci YuPeng Xu FangJun Lu Yong Chen Hua Feng Shu Zhang Sφren Brandt Margarita Hernanz Luca Baldini Enrico Bozzo Riccardo Campana Alessandra De Rosa YongWei Dong Yuri Evangelista Vladimir Karas Norbert Meidinger Aline Meuris Kirpal Nandra Teng Pan Giovanni Pareschi Piotr Orleanski QiuShi Huang Stephane Schanne Giorgia Sironi Daniele Spiga Jiri Svoboda Gianpiero Tagliaferri Christoph Tenzer Andrea Vacchi Silvia Zane Dave Walton ZhanShan Wang Berend Winter Xin Wu Jean J.M.in't Zand Mahdi Ahangarianabhari Giovanni Ambrosi Filippo Ambrosino Marco Barbera Stefano Basso Jörg Bayer Ronaldo Bellazzini Pierluigi Bellutti Bruna Bertucci Giuseppe Bertuccio Giacomo Borghi XueLei Cao Franck Cadoux Francesco Ceraudo TianXiang Chen Yu Peng Chen Jerome Chevenez Marta Civitani Wei Cui WeiWei Cui Thomas Dauser Ettore Del Monte Sergio Di Cosimo Sebastian Diebold Victor Doroshenko Michal Dovciak YuanYuan Du Lorenzo Ducci QingMei Fan Yannick Favre Fabio Fuschino JoséLuis Ga'lvez Min Gao MingYu Ge Olivier Gevin Marco Grassi QuanYing Gu YuDong Gu DaWei Han Bin Hong Wei Hu Long Ji ShuMei Jia WeiChun Jiang Thomas Kennedy Ingo Kreykenbohm Irfan Kuvvetli Claudio Labanti Luca Latronico Gang Li MaoShun Li Xian Li Wei Li ZhengWei Li Olivier Limousin HongWei Liu XiaoJing Liu Bo Lu Tao Luo Daniele Macera Piero Malcovati Adrian Martindale Malgorzata Michalska Bin Meng Massimo Minuti Alfredo Morbidini Fabio Muleri Stephane Paltani Emanuele Perinati Antonino Picciotto Claudio Piemonte JinLu Qu Alexandre Rachevski Irina Rashevskaya Jerome Rodriguez Thomas Schanz ZhengXiang Shen LiZhi Sheng JiangBo Song LiMing Song Carmelo Sgro Liang Sun Ying Tan Phil Uttley Bo Wang DianLong Wang GuoFeng Wang Juan Wang LangPing Wang YuSa Wang Anna L.Watts XiangYang Wen Jörn Wilms ShaoLin Xiong JiaWei Yang Sheng Yang YanJi Yang Nian Yu WenDa Zhang Gianluigi Zampa Nicola Zampa Andrzej A.Zdziarski AiMei Zhang ChengMo Zhang Fan Zhang Long Zhang Tong Zhang Yi Zhang XiaoLi Zhang ZiLiang Zhang BaoSheng Zhao ShiJie Zheng Yu Peng Zhou Nicola Zorzi J.Frans Zwart 2019Science China(Physics,Mechanics & Astronomy)2019,62,2:11
12New yellow Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor for warm-white light-emitting diodes through single-emitting-center conversion显示文摘Phosphor-converted white light-emitting diodes for indoor illumination need to be warm-white(i.e.,correlated color temperature,4000 K)with good color rendition(i.e.,color rendering index.80).However,no single-phosphor,single-emitting-center-converted white light-emitting diodes can simultaneously satisfy the color temperature and rendition requirements due to the lack of sufficient red spectral component in the phosphors’emission spectrum.Here,we report a new yellow Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor that has a new orthorhombic lattice structure and exhibits a broad yellow photoluminescence band with sufficient red spectral component.Warm-white emissions with correlated color temperature,4000 K and color rendering index.80 were readily achieved when combining the Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor with a blue light-emitting diode(440–470 nm).This study demonstrates that warm-white light-emitting diodes with high color rendition(i.e.,color rendering index.80)can be achieved based on single-phosphor,single-emitting-center conversion.Xufan Li John D Budai Feng Liu Jane Y Howe Jiahua Zhang Xiao-Jun Wang Zhanjun Gu Chengjun Sun Richard S Meltzer Zhengwei Pan 2013Light(Science & Applications)2013,2,1:11
13Role of endogenous hormones,glumes,endosperm and temperature on germination of Leymus chinensis(Poaceae)seeds during development显示文摘Aims Leymus chinensis is an original dominant plant in the Songnen grassland,and it has great value for restoration of severely degraded land.However,seeds are dormant,and low germination percentage is a problem for restoring L.chinensis grassland.The mechanism of seed dormancy is not been well understood.The primary aims of the present study were to investigate the dormancy mechanism of L.chinensis seeds(caryopses)with reference to the role of embryo-covering layers,endogenous hormones and temperature.Methods Changes in concentration of the endogenous hormones GA3,indoleacetic acid(IAA),zeatin riboside(ZR)and abscisic acid(ABA)in L.chinensis seeds fromanthesis to maturity weremeasured by the enzymelinked immunosorbent assay method.Germination at different stages of maturity were tested at 16/28C,5/28C and 5/35C for intact seeds with glumes(control),intact seeds with glumes removed(nakedwhole seeds)and intact seeds with glumes and one-half of the endosperm removed(naked-half seeds).Important Findings Of the four endogenous hormones monitored,only the concentration of ZR differed significantly between the beginning and the end of seed development(increased);the GA3/ABA ratio also did not differ.Rank of germination percentage of control at the three temperature regimens was 5/28C>16/28C>5/35C.Germination percentage of the naked-half seeds reached 100%under the three temperature regimens.We concluded that dormancy of L.chinensis seeds is not mainly controlled by endogenous hormones.Germination temperature,mechanical resistance of glumes and inhibition of endosperm are the main factors controlling dormancy and germination of L.chinensis seeds.Hongyuan Ma Zhengwei Liang Haitao Wu Lihua Huang Zhichun Wang 2010Journal of Plant Ecology2010,3,4:11
14Refill friction stir spot welding of 5083-O aluminum alloy显示文摘In this work,refill friction stir spot welding(RFSSW) was used to weld 2 mm-thick 5083-O alloy.The Box–Behnken experimental design was used to investigate the effect of welding parameters on the joint lap shear property.Results showed that a surface indentation of 0.3 mm effectively eliminated the welding defects.Microhardness of the stir zone(SZ) was higher than that of the base material(BM) and the hardness decreased with increasing the heat input during welding.The optimum failure load of 7.72 k N was obtained when using rotating speed of 2300 rpm,plunge depth of 2.4 mm and refilling time of 3.5 s.Three fracture modes were obtained during the lap shear test and all were affected by the hook defect.Zhiwu Xu Zhengwei Li Shude Ji Liguo Zhang 2018Journal of Materials Science & Technology2018,34,5:10
15The High Energy X-ray telescope (HE) onboard the Insight-HXMT astronomy satellite显示文摘The Insight-Hard X-ray Modulation Telescope(Insight-HXMT) is a broadband X-ray and γ-ray(1-3000 ke V) astronomy satellite. One of its three main telescopes is the High Energy X-ray telescope(HE). The main detector plane of HE comprises 18 Na I(Tl)/Cs I(Na) phoswich detectors, where Na I(Tl) is used as the primary detector to measure ~ 20-250 ke V photons incident from the field of view(FOV) defined by collimators, and Cs I(Na) is used as the active shielding detector to Na I(Tl) by pulse shape discrimination. Additionally, Cs I(Na) is used as an omnidirectional γ-ray monitor. The HE collimators have a diverse FOV,i.e. 1.1°×5.7°(15 units), 5.7°×5.7°(2 units), and blocked(1 unit). Therefore, the combined FOV of HE is approximately5.7°×5.7°. Each HE detector has a diameter of 190 mm resulting in a total geometrical area of approximately 5100 cm2, and the energy resolution is ~15% at 60 ke V. For each recorded X-ray event by HE, the timing accuracy is less than 10 μs and the deadtime is less than 10 μs. HE is used for observing spectra and temporal variability of X-ray sources in the 20-250 ke V band either by pointing observations for known sources or scanning observations to unveil new sources. Additionally, HE is used for monitoring the γ-ray burst in 0.2-3 Me V band. This paper not only presents the design and performance of HE instruments but also reports results of the on-ground calibration experiments.CongZhan Liu YiFei Zhang XuFang Li XueFeng Lu Zhi Chang ZhengWei Li AiMei Zhang YongJie Jin HuiMing Yu Zhao Zhang MinXue Fu YiBao Chen JianFeng Ji YuPeng Xu JingKang Deng RenCheng Shang GuoQing Liu FangJun Lu ShuangNan Zhang YongWei Dong TiPei Li Mei Wu YanGuo Li HuanYu Wang BoBing Wu YongJie Zhang Zhi Zhang ShaoLin Xiong Yuan Liu Shu Zhang HongWei Liu YiJung Yang Fan Zhang 2020Science China(Physics,Mechanics & Astronomy)2020,63,4:9
16Bioinspired mineralized collagen scaffolds for bone tissue engineering显示文摘Successful regeneration of large segmental bone defects remains a major challenge in clinical orthopedics,thus it is of important significance to fabricate a suitable alternative material to stimulate bone regeneration.Due to their excellent biocompatibility,sufficient mechanical strength,and similar structure and composition of natural bone,the mineralized collagen scaffolds(MCSs)have been increasingly used as bone substitutes via tissue engineering approaches.Herein,we thoroughly summarize the state of the art of MCSs as tissue-engineered scaffolds for acceleration of bone repair,including their fabrication methods,critical factors for osteogenesis regulation,current opportunities and challenges in the future.First,the current fabrication methods for MCSs,mainly including direct mineral composite,in-situ mineralization and 3D printing techniques,have been proposed to improve their biomimetic physical structures in this review.Meanwhile,three aspects of physical(mechanics and morphology),biological(cells and growth factors)and chemical(composition and cross-linking)cues are described as the critical factors for regulating the osteogenic feature of MCSs.Finally,the opportunities and challenges associated with MCSs as bone tissue-engineered scaffolds are also discussed to point out the future directions for building the next generation of MCSs that should be endowed with satisfactorily mimetic structures and appropriately biological characters for bone regeneration.Zhengwei Li Tianming Du Changshun Ruan Xufeng Niu 2021Bioactive Materials2021,6,5:9
17Geochemical characteristics of the Xuanwei Formation in West Guizhou:Significance of sedimentary environment and mineralization显示文摘The Upper Permian Xuanwei Formation widely occurs in western Guizhou,unconformably overlying the Emeishan basalts,and mainly consists of black shales.It is~170 m thick at Cuyudong Village,Weining County,West Guizhou,China,where the samples of black shale and sandy shale were collected and analyzed.The shales mainly contain SiO2,18.9%?44.1%,Al2O3,14.8%?52.8%,Fe2O3,1.0%?41.2%,LOI,3.2%?21.1%,TiO2,1.0%-6.7%,and MgO,0.2%?2.5%.The contents of all other major elements are lower than 1.0%.It is shown that the black shales have higher contents of Fe2O3 and LOI than normal shales.The siderites occurred in the black shales with higher contents of Fe2O3,which may be attributed to hydrothermal activities on seafloor.All analyzed shale samples have extremely high Ga,47.8×10-6-109.9×10-6(70.5×10-6 on average),higher than the industrial mining standard of Ga Resource Industry Standard.The total contents of rare-earth elements(REE) of 9 black shale samples vary from 213×10-6 to 1460×10-6,suggesting that these black shales are enriched in REE.The shale-normalized REE patterns display both positive and negative Ce anomalies(Ce/Ce* from 0.5 to 1.7),revealing that the Xuanwei shales were precipitated under oxic and anoxic conditions.The Rb-Sr chronological diagram of 6 shale samples in the Xuanwei Formation shows an age of 255±12 Ma.Strontium isotopic ratios(87Sr/86Sr)t0 range from 0.70635 to 0.70711,suggesting that these Xuanwei black shales might be derived from chemical weathering of the Emeishan basalts.ZHANG Zhengwei YANG Xiaoyong LI Shuang ZHANG Zhongshan 2010Chinese Journal Of Geochemistry2010,29,4:9
18Effect of Reverse-threaded Pin on Mechanical Properties of Friction Stir Lap Welded Alclad 2024 Aluminum Alloy显示文摘In friction stir welding(FSW), tool geometry plays an important role in joint quality. In order to improve mechanical properties of friction stir lap welding(FSLW) joint, a tool with a reverse-threaded pin was designed in the present study. Using 2024-T4 aluminum alloy as the research object, tools with the fullthreaded pin and reverse-threaded pin were used in FSLW. Results showed that, when using the same parameter combination, FSLW joint using the reverse-threaded pin owned bigger effective sheet thickness(EST), bigger lap width and better lap shear failure strength. Compared with the full-threaded pin,fracture mode of the FSLW joint changed from shear fracture mode to tensile fracture mode when the reverse-threaded pin was used. Fracture morphologies presented ductile fracture.Yumei Yue Zhengwei Li Shude Ji Yongxian Huang Zhenlu Zhou 2016Journal of Materials Science & Technology2016,32,7:9
19Cybersecurity Named Entity Recognition Using Bidirectional Long Short-Term Memory with Conditional Random Fields显示文摘Network texts have become important carriers of cybersecurity information on the Internet.These texts include the latest security events such as vulnerability exploitations,attack discoveries,advanced persistent threats,and so on.Extracting cybersecurity entities from these unstructured texts is a critical and fundamental task in many cybersecurity applications.However,most Named Entity Recognition(NER)models are suitable only for general fields,and there has been little research focusing on cybersecurity entity extraction in the security domain.To this end,in this paper,we propose a novel cybersecurity entity identification model based on Bidirectional Long Short-Term Memory with Conditional Random Fields(Bi-LSTM with CRF)to extract security-related concepts and entities from unstructured text.This model,which we have named XBi LSTM-CRF,consists of a word-embedding layer,a bidirectional LSTM layer,and a CRF layer,and concatenates X input with bidirectional LSTM output.Via extensive experiments on an open-source dataset containing an office security bulletin,security blogs,and the Common Vulnerabilities and Exposures list,we demonstrate that XBi LSTM-CRF achieves better cybersecurity entity extraction than state-of-the-art models.Pingchuan Ma Bo Jiang Zhigang Lu Ning Li Zhengwei Jiang 2021Tsinghua Science and Technology2021,26,3:9
20Effect of treatment course of comprehensive intervention with Traditional Chinese Medicine on mortality of acquired immunodeficiency syndrome patients treated with combined antiretroviral therapy显示文摘OBJECTIVE:To investigate the effect of a treatment course of comprehensive intervention with Traditional Chinese Medicine(TCM) on the mortality of patients with acquired immunodeficiency syndrome(AIDS) treated with combined antiretroviral therapy(c ART).METHODS:AIDS patients who had taken c ART in a national TCM human immunodeficiency virus treatment trial program(NTCMTP) before 2009 were enrolled in this study and followed for 36 months from November 2009.Patients enrolled in the NTCMTP in 2004 were taken as the first group,those enrolled in 2006 as the second group,and those enrolled in 2009 as the third group.Cumulative survival rates were calculated by the life table method.Survival curves for subgroups were compared by the log-rank test.Hazard ratios were calculated with a Cox proportional hazards model.RESULTS:A total of 1443 AIDS patients were followed for 3 years(4198 person-years).During this period,91(6.3%) patients died and 13(0.9%) were lost to follow-up.The total mortality rate was 2.17/100 person-years.The mortality rate of patients enrolled in the NTCMTP in 2004 was 1.49/100 person-years,which was lower than that of patients enrolled in 2006(2.23/100 person-years) and 2009(3.48/100 person-years).After adjusting for other factors,a shorter time of treatment with TCM,male sex,older age,lower CD4 + T-cell counts,and long-term treatment with c ART were risk factors of mortality.CONCLUSION:Long-term treatment with TCM decreased the mortality risk of AIDS patients.Factors such as being male,older age,CD4+ T-cell counts,and time of treatment with TCM and c ART were correlated with mortality.Guo Huijun Wang Jian Li Zhengwei Jiang Ziqiang Xu Qianlei Xu Liran 2016Journal of Traditional Chinese Medicine2016,36,4:9
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