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Immunology of Stem Cells and Cancer Stem Cells

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Cellular & Molecular Immunology 2007年第3期4卷 161-171页

作者： Xiao-feng yang Department of Pharmacology Temple University School of Medicine Philadelphia PA 19140 USA

The capacity of pluri-potent stem cells to repair the tissues in which stem cells reside holds great promise in development of novel cell replacement therapeutics for treating chronic and degenerative diseases. However, numerous reports show that stem cell therapy, even in an autologous setting, triggers lymphocyte infiltration and inflammation. Therefore, an important question to be answered is how the host immune system responds to engrafted autologous stem cells or allogeneous stem cells. In this brief review, we summarize the progress in several related areas in this field, including some of our data, in four sections：（1） immunogenicity of stem cells; （2） strategies to inhibit immune rejection to allograft stem cells; （3） immune responses to cancer stem cells; and （4） mesenchymal stem cells in immune regulation. Improvement of our understanding on these and other aspects of immune system-stem cell interplay would greatly facilitate the development of stem cell-based therapeutics for regenerative purposes. Cellular ＆ Molecular Immunology.

关键词： immunogenicity stem cell therapy cancer stem cells stimulation-responsive splicing model

Fabrication of silica-based ceramic cores with internal lattice structures by stereolithography

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China Foundry 2022年第5期19卷 369-379页

作者： Ke-hui Hu Hao-yuan Wang Kuan Lu Qian feng dao-ding yang Jian Cao Bo Zhang Zhi-gang Lü Xing Ran State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Ten Dimensions(Guangdong)Technology Co. Ltd.Foshan 528225GuangdongChina Guizhou Anji Aviation Investment Casting Co. Ltd.Anshun 561003GuizhouChina Key Laboratory of Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China

Ceramic cores are widely used in investment casting,and ideal properties of cores are essential for high-quality *** the circumstances requiring thick cores,solid cores are likely to encounter deformation and cracking defects due to the accumulation of ***,with the superiority of ceramic stereolithography in producing complex ceramic parts,hollow cores with lattice structures were designed and *** dimensional accuracy and properties of the green and sintered bodies were *** show the dimensional accuracy of sintered cores is controlled within±0.25 mm benefited from the precise green *** mechanical properties are not obviously *** bending strength reaches 11.94 MPa at room temperature and 12.87 MPa at 1,500℃ with a creep deformation of 0.345 ***,casting verifications prove that the hollow cores meet the requirements of investment *** casting surfaces are obtained,at the same time,the core-removal efficiency is improved by over 3 times.

关键词： silica ceramic cores stereolithography lattice structure investment casting

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驱控一体的旋拧式果实采摘执行器设计与试验

农机化研究 2025年第3期47卷 48-55页

作者：严童杰冯青春郭鑫杨宁江苏大学电气信息工程学院江苏镇江212000 北京市农林科学院智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 农业智能装备技术北京市重点实验室北京100097

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并... 详细信息

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并设计了基于双舵机驱动的紧凑型采摘执行机构,对其吸盘、夹持和旋拧电机的关键参数进行了优化设计。面向多执行并行采摘需要,设计了基于CANopen通讯的采摘操作驱动器,实现了多执行器的总线扩展。通过现场试验对执行器作业性能进行了测试,结果表明:果实大小在60~100 mm之间,采摘成功率可达到90%,吸盘最优停留时间为1.00 s,吸盘最优接近距离为1.0 mm,最优旋拧角度为360°。

关键词：采摘机器人驱控一体旋拧采摘 CANopen

Fast degree-distribution optimization for BATS codes

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Science China(Information Sciences) 2017年第10期60卷 124-138页

作者： Huakai ZHAO Shenghao yang Guinian feng Beijing Satellite Navigation Center The Chinese University of Hong Kong Beijing Institute of Tracking and Communication Technology

Batched sparse(BATS) codes have been proposed for communication through networks with packet loss. BATS codes include a matrix generalization of fountain codes as the outer code and random linear network coding at the intermediate network nodes as the inner code. BATS codes, however, do not possess a universal degree distribution that achieves an optimal rate for any distribution of the transfer matrix ranks. Therefore,it is important to have a fast degree-distribution optimization approach for finite-length BATS codes. In this paper, we propose the concept of batch release probability(BRP), and demonstrate some characteristics of BRPs from the degree distributions achieving nearly optimal performance. Based on these BRP characteristics,we propose a novel degree-distribution optimization approach that achieves the similar decoding performance with a much shorter optimization time, compared with the previous approach. Moreover, the universality of BRPs observed in this paper can further simplify the degree-distribution optimization of BATS codes.

关键词： network coding batched sparse(BATS) code finite-length analysis degree distribution batch release probability optimization

Formation mechanism of titanium and niobium carbides in hardfacing alloy

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Rare Metals 2017年第8期36卷 640-644页

作者： Ke yang Kèyang Ye-feng Bao Yong-feng Jiang College of Mechanical and Electrical Engineering Hohai UniversityChangzhou 213022China

The most effective carbide-forming elements titanium and niobium were added into hardfacing *** and composition of carbides in the hardfacing alloy were investigated by means of optical microscope（OM）,scanning electron microscope（SEM）,X-ray diffraction（XRD）and energy-dispersive spectrometer（EDS）.Hardness and impact toughness of the hardfacing alloy were *** thermodynamics and formation mechanism of carbides were also *** is found that the carbides consist of TiC and NbC which are able to form directly from welding pool during the welding *** formation mechanism of carbides involves nucleation of TiC followed by epitaxial precipitation of NbC on the surface of *** formation of titanium and niobium carbides can obviously refine the microstructure and deplete the carbon in the *** micros tructure transforms to well-distributed carbides and a tough martensite matrix,contributing to a good combination of high hardness and high toughness in the hardfacing alloy.

关键词： Titanium Niobium Hardfacing alloy Carbides Microstructure

The battle of crops against drought:Genetic dissection and improvement

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Journal of Integrative Plant Biology 2023年第2期65卷 496-525页

作者： Zhirui yang feng Qin State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China

With ongoing global climate change,water scarcity-induced drought stress remains a major threat to agricultural *** undergo a series of physiological and morphological changes to cope with drought stress,including stomatal closure to reduce transpiration and changes in root architecture to optimize water *** phenotypic and multi-omics studies have recently identified a number of drought-related genetic resources in different crop *** functional dissection of these genes using molecular techniques has enriched our understanding of drought responses in crops and has provided genetic targets for enhancing resistance to ***,we review recent advances in the cloning and functional analysis of drought resistance genes and the development of technologies to mitigate the threat of drought to crop production.

关键词： crops drought resistance gene cloning genetic improvement

On Fridman Invariants and Generalized Squeezing Functions

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Chinese Annals of Mathematics,Series B 2022年第2期43卷 161-174页

作者： feng RONG Shichao yang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China Corresponding author.School of Mathematics and Statistics Huizhou UniversityHuizhou 516007GuangdongChina

In this paper,the authors introduce the notion of generalized squeezing function and study the basic properties of generalized squeezing functions and Fridman *** also study the comparison of these two invariants,in t... 详细信息

关键词： Fridman invariant Squeezing function Quotient invariant

Experimental study of enhancing coalbed methane recovery by carbon dioxide injection driving methane

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Journal of Coal Science & Engineering(China) 2010年第4期16卷 356-361页

作者： LUO dao-cheng LIU Jun-feng School of Chemistry and Technology Hunan University of Science and Technology Xiangtan 411201 China

In order to enhance coalbed methane recovery, taking a self-developed largecalesimulation system for the platform, a modeling experiment of driving CH_4 by CO_2 gasinjection was *** results of experiment indicates that there is a significant lag effectof adsorption and desorption on gas, the gas pressure is changed more rapidly in theprocess of carbon dioxide adsorption of coal than methane adsorption of coal; After theinjection of carbon dioxide, compare with methane single *** an early stage,speed and amount of methane single desorption are greater than the speed and amountof displacement desorption, the speed and amount of displacement desorption *** the process of replacement, CH_4 concentration constantly declined, while CO_2concentration constantly *** the process of CO_2 gas injection, the temperature of coalhave been significantly increased, it is more beneficial to make CH_4 gas molecules becomefree from the adsorbed state when temperature is *** the pressurestep-down at the same rate, using the method of CO_2 driving CH_4, compared with themethod of conventional pressure step-down, the desorption rate of CH_4 in coal can beraised about 2.13 times, at the same time, a lot of greenhouse gas CO_2 will also be buriedin the ground, there is a very significant environmental benefit.

关键词： carbon dioxide injection replacement experiment coalbed methane desorption methane recovery

Surface-enhanced Raman Scattering of Self-assembled Superstructures

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Chemical Research in Chinese Universities 2021年第5期37卷 989-1007页

作者： feng Enduo TIAN yang School of Chemistry and Molecular Engineering East China Normal UniversityShanghai200241P.R.China

Surface-enhanced Raman scattering(SERS)is a molecular specific spectroscopic technique that amplifies the Raman signal of absorbed molecules for up to 1010 *** the past decades,SERS substrates experienced rapid growth,resulting in excellent development for SERS *** the surface plasmonic resonance coupling between individual materials can form a“hotspot”region to maximize the Raman signal.

关键词： SERS Surface Raman