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加拿大棘球绦虫G7基因型研究进展

中国人兽共患病学报 2024年第6期40卷 548-555页

作者：朱小伟华瑞其邵国庆杨光友四川农业大学动物医学院动物寄生虫病研究中心成都611130

囊型包虫病是一种严重危害人类健康的人兽共患寄生虫病。作为该病的病原之一,加拿大棘球绦虫G7基因型日渐成为囊型包虫病患者患病的重要病因。近年来,其流行区域有着逐渐扩大的趋势,因而从流行病学角度全面认识其对人和家畜的危害有着... 详细信息

囊型包虫病是一种严重危害人类健康的人兽共患寄生虫病。作为该病的病原之一,加拿大棘球绦虫G7基因型日渐成为囊型包虫病患者患病的重要病因。近年来,其流行区域有着逐渐扩大的趋势,因而从流行病学角度全面认识其对人和家畜的危害有着不容忽视的重要意义。本文全面总结了加拿大棘球绦虫G7基因型的流行特征,并对其生物学特性、线粒体基因组与基因组特征、分子遗传标记及防控进行综述,以期为我国的加拿大棘球绦虫G7基因型的分子流行病学调查和防控措施的制定提供参考。

关键词：加拿大棘球绦虫G7基因型流行特征生物学特性分子遗传标记防控

Numerical simulation of solidification and liquation behavior during welding of low-expansion superalloys

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Frontiers of Materials Science 2011年第2期5卷 146-159页

作者： shao-qing guo Xiao-Hong LI Beijing Institute of Aeronautical Materials Beijing 100095 China

Low-expansion superalloys are susceptible to weld solidification cracks and heat,affected zone （HAZ）microflssures. To predict solidification cracking, QBasic procedures were developed and solidification reaction sequence, type, and amount of eutectic product were caiculated As manifested, primary solidification is followed by L→（Y＋ NbC） and L → （Y＋ Laves） eutectic reaction sequentially for G H903 and GH907; hence, the terminal eutectic constitue Y/Laves, While for GH909, intsare made up of Y/NbC and Y/only reaction L → （Y ＋ Laves） occurs and more Y/Laves eutectic forms. Therefore, GH909is more sensitive to solidification cracking. To predict HAZ liquation, cracking Visual FORTRAN procedures were developed, and constitutional liquation of NbC was simulated. As shown, solid dissolution of NbC prior to liquation decreases, and initial liquid film increases with the rate of thermal cycle. Higher rate of thermal cycle promotes the melting of the matrix adjacent to the liquid film and postpones the solidification of the at the eutectic n size and peak rifled indirectly by hot ductility tests.

关键词： solidification cracking HAZ microfissuring constitutional liquation lowexpansion superalloy numerical simulation

Influence of hot isostatic pressing on microstructure,properties and deformability of selective laser melting TC4 alloy

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China Foundry 2021年第4期18卷 389-396页

作者： Tai-qi Yan Bing-qing Chen Xia Ji shao-qing guo 3D Printing Research and Engineering Technology Center Beijing Institute of Aeronautical MaterialsBeijing 100095China Falcon Fast Manufacturing Technology Co. Ltd.Wuxi 214145JiangsuChina

The influence of different hot isostatic pressing regimes on microstructure,phase constitution,microhardness,tensile properties and deformability of TC4 alloy fabricated by selective laser melting(SLM)technology was *** results show that the microstructure of SLM TC4 alloy is composed of acicular martensiteα’phase,and the sample exhibits high microhardness and strength,but low *** hot isostatic pressing,acicular martensiteα’phase transforms intoα+βphase,and with the increase of hot isostatic pressing temperature and duration,αphase with coarse lath is gradually refined,and the proportion ofαphase is gradually *** of the change of phase constitution in SLM TC4 alloy after hot isostatic pressing,the grain refinement strengthening is weakened,the density of dislocation is reduced,so that both microhardness and tensile strength are decreased by around 20%,the elongation is increased by more than about 70%,even over 100%,compared with as-deposited TC4 *** the hot isostatic pressing regime is 940°C/3 h/150 MPa,the tensile strength and the elongation achieve optimal match,which are about890 MPa and around 14.0%in both *** fracture mechanism of alloy after 940 oC/3 h/150 MPa HIP is dultile *** isostatic pressing causes concave deformation of SLM TC4 alloy thin-walled frames,and the deformation degree increases with the increase of temperature.

关键词： selective laser melting TC4 alloy hot isostatic pressing microstructure mechanical properties deformability

Microstructure Characteristics and Mechanical Properties of Nb-17Si-23Ti Ternary Alloys Fabricated by In Situ Reaction Laser Melting Deposition

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Acta Metallurgica Sinica(English Letters) 2018年第4期31卷 362-370页

作者： Wei Liu Hua-Ping Xiong Neng Li shao-qing guo Ren-Yao Qin 3D Printing Research and Engineering Technology Center Beijing Institute of Aeronautical MaterialsBeijing 100095China

Fabrication of ternary Nb-17Si-23Ti alloys was attempted by in situ reaction laser melting deposition（LMD）with dual powder feeding method from Nb-28 at.% Ti powder mixture and pure Si *** microstructures of the as-deposited alloys were examined with scanning electronic microscope,and the phase constituents were analyzed by X-ray energy-dispersive spectrometer and X-ray ***,the effect of laser power on microstructure charac-teristics,microhardness and indentation fracture toughness was also *** in situ reaction LMD process resulted in remarkable refinement of the *** as-deposited samples mainly consisted of Nbss,metastable（NbTi）3Si and Ti-rich *** the increase in the laser power from 1000 to 2000 W,the Nbss morphology changed from discontinuous dendritic to near equiaxed,but the Ti-rich Nbss phase tended to ***,with the increase in the laser power,the microhardness of as-deposited samples increased from 822 to 951 HV,while the indentation fracture toughness was improved from 12.3 to 14.1 MPa mt/*** corresponding mechanism is also discussed.

关键词： Nb-Si-Ti alloys Laser melting deposition Microstructure Mechanical properties In situreaction

Microstructure and properties of AlSi7Mg alloy fabricated by selective laser melting

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China Foundry 2021年第4期18卷 416-423页

作者： Shuai Huang shao-qing guo Biao Zhou guo-hui Zhang Xue-jun Zhang 3D Printing Research and Engineering Technology Center Beijing Institute of Aeronautical MaterialsBeijing 100095China

The AlSi7Mg alloy was fabricated by selective laser melting(SLM),and its microstructure and properties at different building directions after heat treatment were *** show that the microstructure of SLM AlSi7Mg samples containes three zones:fine grain zone,coarse grain zone,and heat affected *** fine-grain regions locate inside the molten pool,and the grains are *** coarse-grain regions locate in the overlap of molten *** T6 treatment,the microstructure at the molten pool boundary is still the network eutectic Si,but the network structure becomes discrete,and is composed of intermittent,chain-like eutectic Si *** yield strength at three directions(xy,45°,z direction)of the AlSi7Mg alloy samples fabricated by SLM is improved after T6 heat *** fracture mechanism of the samples is a mixed ductile and brittle fracture before heat treatment and ductile fracture after heat treatment.

关键词： selective laser melting AlSi7Mg alloy microstructure mechanical property

Liposomalα-cyperone targeting bone resorption surfaces suppresses osteoclast differentiation and osteoporosis progression via the PI3K/Akt axis

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Nano Research 2024年第4期17卷 2949-2959页

作者： Lin Yang Xueying An Wang Gong Wenshu Wu Bin Liu Xiaoyan shao Yansi Xian Rui Peng Baosheng guo qing Jiang Division of Sports Medicine and Adult Reconstructive Surgery Department of Orthopedic SurgeryNanjing Drum Tower Hospital Clinical College of Nanjing Medical University321 Zhongshan RoadNanjing 210008China Branch of National Clinical Research Center for Orthopedics Sports Medicine and RehabilitationNanjing 210008China State Key Laboratory of Pharmaceutical Biotechnology Medical SchoolNanjing University&Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Osteoporosis is a metabolic dysregulation of bone that occurs mainly in postmenopausal women,and the hyperfunction of osteoclasts is the primary contributor to postmenopausal ***,the development of effective therapeutic drugs and precise delivery systems remains a challenge in the field of anti-absorption ***,we reported theα-cyperone(α-CYP)for anti-osteoporosis and developed a liposome-based nano-drug delivery system ofα-CYP,that specifically targets the bone resorption ***,we found that theα-CYP,one of the major sesquiterpenes of Cyperus rotundus L.,attenuated the progression of osteoporosis in ovariectomized(OVX)mice and down-regulated the expression of phosphorylated proteins of phosphoinositide 3-kinase(PI3K)and protein kinase B(Akt),causing down-regulation of osteoclast-related genes/proteins and curbing osteoclast ***,α-CYP reversed the activation of osteoclastic differentiation and enhanced osteoporosis-related proteins expression caused by PI3K/Akt agonist(YS-49).More importantly,we adopted the osteoclastic resorption surface targeting peptide Asp8 and constructed the liposome(lipαC@Asp8)to deliverα-CYP to osteoclasts and confirmed its anti-osteoporosis effect and enhanced osteoclast inhibition by blocking PI3K/Akt *** conclusion,this study demonstrated thatα-CYP inhibits osteoclast differentiation and osteoporosis development by silencing PI3K/Akt pathway,and the liposome targeting delivery systems loaded withα-CYP might provide a novel and effective strategy to treat osteoporosis.

关键词： osteoporosis α-cyperone osteoclast phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) liposome

Research on light dark matter particle from evaporating primordial black hole in CDEX-10 experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 168-169页

作者： qing-guo Huang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

Dark matter is an essential component of the universe,accounting for approximately 85%of all ***,what the nature of dark matter actually is remains a huge *** far,all evidence for the existence of dark matter has come from gravitational *** gravitational interactions are universal,it is challenging to reveal the nature of dark matter through gravitational *** unravel the mystery of dark matter,it is essential to directly detect dark matter.

关键词： approximate particle gravitational

Escape probability for isotropic emitters near Kerr black hole with astrometric

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Communications in Theoretical Physics 2024年第5期76卷 128-133页

作者： Yu-Xuan Han qing-Hua Zhu qing-guo Huang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCASHangzhou 310024China

The paper investigates the escape probability for isotropic emitters near a Kerr black *** propose a new approach to obtain the escape probability in a general manner,going beyond previous case-by-case *** approach is based on studies of the black hole shadow with astrometric observable and can be applied to emitters with an arbitrary 4-velocities and locations,even to the emitters outside of the equatorial *** also consider representative examples illustrating how escape probabilities vary with distance,velocity,and inclination ***,this new approach provides an effective method for studying escape probabilities near Kerr black holes.

关键词： Kerr black hole photon escape probability isotropic emitters

Distribution of oxide inclusions in H13 castings under super-gravity field with multi-stage rotation speeds

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Journal of Iron and Steel Research International 2024年第1期31卷 121-133页

作者： shao-ying Li Xiao-jun Xi Xing-ming Zhao Han-jie guo Jing guo School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Beijing Beiye Functional Materials Corporation Beijing100192China Shandong Tianwu Forming Technology Co. Ltd.Liaocheng252024ShandongChina

The 42 kg industrial H13 castings were prepared by different super-gravity fields with multi-rotation speeds,and the distribution of oxide inclusions in the castings was *** addition,the inward movement Reynolds number and inward movement time of oxide inclusions as well as the solidification time of molten steel at different positions in the castings were calculated to clarify the removal mechanism of oxide inclusions in super-gravity *** results show that the large size(i.e.,greater than 10μm)oxide inclusions are mainly concentrated in the inner and outer parts of the super-gravity castings with constant rotation speed(500 r min^(-1))and five-stage rotation speeds(500,600,750,850,and 950 r min^(-1)),respectively,while there are no large oxide inclusions in the super-gravity castings with three-stage rotation speeds(500,600,and 750 r min^(-1)).Although an increase in the particle size of inclusion and the rotation speed in super-gravity field is conducive to the increase in the inward movement Reynolds number of oxide inclusions and reduction in the inward movement time of oxide inclusions,it will reduce the local solidification time of molten *** the range of the rotation speed studied,the super-gravity field with three-stage rotation speeds has the best effect on the removal of inclusions in H13 molten steel.

关键词： Distribution Oxide inclusion H13 casting Super-gravity field Rotation speed