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LOW DOSE IONIZING RADIATION DOES NOT CAUSE RATIO CHANGES OF REGULATORY T SUBSETS IN MOUSE SPLEEN

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吉林大学学报(医学版) 1992年第3期 209-213页

作者： liu shuzheng, qi jin , zhang yingchun(MPH Radiobiology Research Unit, PRC, Changchun)

C57BL/6 mice were whole-body irradiated with 75 mGy X-rays with or without SRBC immunization. The splenic lymphocytes were analyzed by flow cytometry with fluorescent monoclonal antibodies 4 and 7 days after irradiation. No significant changes were found in the ratio of helper to suppressor T lymphocytes after irradiation, no matter it was calculated from the percentage or the absolute number of the subsets. However, 4 days after irradiation plus immunization, the ratio was higher than that in the group with irradiation alone and that in the group with immunization alone probably due to the significant increase in number of the helper T cells in the spleen. The present study demonstrated that ionizing radiation per se in a dose within 0. 1 Gy would not significantly change the ratio of regulatory T subsets.

关键词： Low dose radiation T subsets Immunoenhancement

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裂隙中煤粉运移及解堵可视化物理模拟实验

煤炭学报 2024年第3期49卷 1488-1500页

作者：魏迎春张琦刘子亮李彪谢天成任金伟王安民曹代勇中国矿业大学(北京)地球科学与测绘工程学院北京100083 中国矿业大学(北京)煤炭精细勘探与智能开发全国重点实验室北京100083

煤粉在煤储层裂隙中沉积会降低裂隙导流能力,制约煤层气井高效稳产开发。设计了裂隙中煤粉运移及解堵可视化物理模拟实验方案,通过裂隙中煤粉运移可视化物理模拟实验,分析了裂隙不同位置煤粉颗粒沉积面积的变化和沉积形态特征,揭示了煤... 详细信息

煤粉在煤储层裂隙中沉积会降低裂隙导流能力,制约煤层气井高效稳产开发。设计了裂隙中煤粉运移及解堵可视化物理模拟实验方案,通过裂隙中煤粉运移可视化物理模拟实验,分析了裂隙不同位置煤粉颗粒沉积面积的变化和沉积形态特征,揭示了煤粉运移、沉积的动态规律;通过裂隙中煤粉解堵可视化物理模拟实验,分析了解堵时间和流速对裂隙中沉积煤粉解堵面积的影响,揭示了煤粉启动、解堵的动态规律。实验结果表明:煤粉颗粒在裂隙不同方向和位置聚集状态不同,裂隙喉道由入口向垂直主运移方向的两端及主运移方向煤粉颗粒沉积面积逐渐减少,支路通道沿主运移方向煤粉颗粒沉积面积逐渐增加。裂隙喉道、支路通道和主路通道处煤粉沉积的形态分别呈鹰嘴状、层状和流线型,其原因是裂隙不同位置对含煤粉流体的阻力不同,导致煤粉在不同位置的沉积形态不同。在相同流速下,随解堵时间增长,煤粉解堵效果越好,但前期解堵面积大,后期解堵面积小,裂隙喉道处煤粉解堵效果明显优于支路通道,其原因是松散、易于解堵的煤粉颗粒会被首先解堵,随时间进行,剩余未被解堵的煤粉颗粒需要更大的启动流速。流速越大,裂隙喉道处和支路通道处的煤粉解堵面积越大,其原因是提升流速能增强煤粉颗粒的流动性。

关键词：煤层气煤粉运移煤粉解堵可视化物理模拟实验

THYMOCYTE RENEWAL AND DIFFERENTIATION IN MICE FOLLOWING LOW DOSE IONIZING RADIATION

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吉林大学学报(医学版) 1992年第5期 405-408页

作者： liu shuzheng,zhang yingchun, qi jin(MPH Radiobiology Research Unit,PRC) 长春 MPH Radiobiology Research Unit

Whole-body irradiation (WBI) with 75 mGy X-rays to Kunming mice caused an increase in percentage of thymocytes driven into S phase of the cell cycle at the expense of the GoGl cells 3 to 7 days after irradiation. At the same time the percentage of CD4-CD8- cells in the thymus (immature thymocytes and prothymocytes) was found to be significantly higher than that in the sham-irradiated control. There was neither a preferential decrease in the CD8+cells nor a rise of the ratio of CD4+ to CD8+ cells. The implications of these observations were discussed.

关键词： Thymocytes Cell cycle T subsets Low dose radiation

Does olw dose radiation increase thymocyte death

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吉林大学学报(医学版) 1994年第3期 213-216页

作者： liu shuzheng,Li Xiuyi,zhang yingchun,Lu Zhe And qi jin (MPH Radiobiologyresearch Unit)

ＤｏｅｓｌｏｗＤｏｓｅＲａｄｉａｔｉｏｎＩｎｃｒｅａｓｅＴｈｙｍｏｃｙｔｅＤｅａｔｈＬｉｕＳｈｕｚｈｅｎｇ，ＬｉＸｉｕｙｉ，ＺｈａｎｇＹｉｎｇｃｈｕｎ，ＬｕＺｈｅＡｎｄＱｉＪｉｎ（ＭＰＨＲａｄｉｏｂｉｏｌｏｇｙｒｅｓ... 详细信息

ＤｏｅｓｌｏｗＤｏｓｅＲａｄｉａｔｉｏｎＩｎｃｒｅａｓｅＴｈｙｍｏｃｙｔｅＤｅａｔｈＬｉｕＳｈｕｚｈｅｎｇ，ＬｉＸｉｕｙｉ，ＺｈａｎｇＹｉｎｇｃｈｕｎ，ＬｕＺｈｅＡｎｄＱｉＪｉｎ（ＭＰＨＲａｄｉｏｂｉｏｌｏｇｙｒｅｓｅａｒｃｈＵｎｉｔ）Ｄｏｅｓｌｏｗ...

关键词： low dose radiation, thymocyte/RE, cell survival/RE, cell division/RE cell suicide cell proliferation ,dose-response relationship,radiation

Radiationeffectsonthymocyteapoptosis

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吉林大学学报(医学版) 1995年第6期 551-558页

作者： liu shuzheng,zhang yingchun,Mu Ying,liu Jianxiang(MPN Radiobiology Research Unit,PRC)

ＲａｄｉａｔｉｏｎｅｆｆｅｃｔｓｏｎｔｈｙｍｏｃｙｔｅａｐｏｐｔｏｓｉｓＬｉｕＳｈｕｚｈｅｎｇ，ＺｈａｎｇＹｉｎｇｃｈｕｎ，ＭｕＹｉｎｇ，ＬｉｕＪｉａｎｘｉａｎｇ（ＭＰＮＲａｄｉｏｂｉｏｌｏｇｙＲｅｓｅａｒｃｈＵｎｉ... 详细信息

ＲａｄｉａｔｉｏｎｅｆｆｅｃｔｓｏｎｔｈｙｍｏｃｙｔｅａｐｏｐｔｏｓｉｓＬｉｕＳｈｕｚｈｅｎｇ，ＺｈａｎｇＹｉｎｇｃｈｕｎ，ＭｕＹｉｎｇ，ＬｉｕＪｉａｎｘｉａｎｇ（ＭＰＮＲａｄｉｏｂｉｏｌｏｇｙＲｅｓｅａｒｃｈＵｎｉｔ，ＰＲＣ）Ｒａｄｉａｔｉｏｎｅｆ...

关键词： radiation thymocyte apoptosis J-shaped curve

Dogs lacking Apolipoprotein E show advanced atherosclerosis leading to apparent clinical complications

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Science China(Life Sciences) 2022年第7期65卷 1342-1356页

作者： Hui Zhao Jianping Zhao Di Wu Zhaolin Sun Yang Hua Min Zheng Yumei liu qi Yang Xiahe Huang Yuan Li Yueshan Piao yingchun Wang Sin Man Lam Huijuan Xu Guanghou Shui Yongjun Wang Haifeng Yao Liangxue Lai Zhuo Du Jidong Mi Enqi liu Xunming Ji Yong Q.zhang Key Laboratory of Molecular Developmental Biology and CAS Center for Excellence in Brain Science and Intelligence TechnologyInstitute ofGenetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Guangzhou Institutes of Biomedicine and Health Chinese Academy of SciencesGuangzhou 510530China Beijing Sinogene Biotechnology Co.Ltd Beijing 102200China Xuanwu Hospital Capital Medical UniversityBeijing 100053China TianTan Hospital Capital Medical UniversityBeijing 100070China Beijing Petsguard Animal Hospital Beijing 100192China Laboratory Animal Center Xi’an Jiaotong University Health Science CenterXi’an 710049China

Atherosclerotic cardiovascular disease resulting from dysregulated lipid metabolism is the leading cause of morbidity and mortality *** E(ApoE)plays a critical role in cholesterol *** in lipid-metabolizing proteins including ApoE in multiple model organisms such as mice and rats exhibiting elevated levels of cholesterol have been widely used for dissecting the pathology of atherosclerosis,but few of these animal models exhibit advanced atherosclerotic plaques leading to ischemia-induced clinical symptoms,limiting their use for translational *** we report hypercholesterolemia and severe atherosclerosis characterized by stenosis and occlusion of arteries,together with clinical manifestations of stroke and gangrene,in ApoE knockout dogs generated by CRISPR/Cas9 and cloned by somatic cell nuclear transfer ***,the hypercholesterolemia and atherosclerotic complications in F0 mutants are recapitulated in their *** the ApoE-associated atherosclerosis and clinical manifestations in mutant dogs are more similar to that in human patients compared with those in other animal models,these mutant dogs will be invaluable in developing and evaluating new therapies,including endovascular procedures,against atherosclerosis and related disorders.

关键词： ApoE atherosclerosis hypercholesterolemia gangrene stroke

SARS-CoV-2与受体ACE2独特的相互作用与结合/解离过程

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中国科学：化学 2022年第5期52卷 721-730页

作者：刘深鑫张博刘迎春王琦浙江大学化学系杭州310027

2019年12月由新型肺炎冠状病毒(SARS-Co V-2)感染导致的肺炎(COVID-19)疫情大规模爆发,并于2020年3月被世界卫生组织宣布为全球大流行.其显著的传染性和致死率对全人类的生命安全构成了巨大的威胁,迫切需要从分子层面上了解并掌握病毒... 详细信息

2019年12月由新型肺炎冠状病毒(SARS-Co V-2)感染导致的肺炎(COVID-19)疫情大规模爆发,并于2020年3月被世界卫生组织宣布为全球大流行.其显著的传染性和致死率对全人类的生命安全构成了巨大的威胁,迫切需要从分子层面上了解并掌握病毒的感染/传播行为.新冠病毒和2003年爆发的严重急性呼吸系统综合征冠状病毒(SARS-Co V)同属于蝙蝠SARS样冠状病毒(SARSr-Co V)物种,其表面刺突糖蛋白具有高度的同源性,它们侵入人体细胞的关键步骤同为表面刺突蛋白的受体结合域(RBD)部分和人血管紧张素转化酶2(ACE2)的结合,许多实验工作报道了SARS-Co V-2拥有比SARS-Co V更强的结合能力.为了进一步诠释实验结果,本工作对这两种病毒的野生型RBD(RBDWT)和ACE2的结合进行了分子动力学模拟、拉伸分子动力学模拟和伞状取样,结果表明,β-loop区的不同行为导致关键结合残基和相互作用的不同,并进一步导致结合/解离机制的不同,SARS-Co V-2-RBD和ACE2的结合亲和力是SARS-Co V-RBD的约30倍.

关键词： SARS-CoV-2 SARS-CoV 拉伸分子动力学伞状取样关键结合残基结合自由能

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水化学性质对支撑裂缝中煤粉运移的影响

煤炭学报 2023年第9期48卷 3483-3493页

作者：刘子亮魏迎春张琦张双源王安民曹代勇中国矿业大学(北京)地球科学与测绘工程学院北京100083 中国矿业大学(北京)煤炭资源与安全开采国家重点实验室北京100083 中联煤层气国家工程研究中心有限责任公司北京100095 中石油煤层气有限责任公司北京100028

煤粉问题制约我国煤层气的高效开发。选用韩城矿区山西组3号煤层煤岩样品,开展不同水化学性质对支撑裂缝中煤粉运移影响的物理模拟试验,分析裂缝导流系统渗透率及煤粉产出质量浓度变化,探究不同水化学性质对支撑裂缝中煤粉运移的影响。... 详细信息

煤粉问题制约我国煤层气的高效开发。选用韩城矿区山西组3号煤层煤岩样品,开展不同水化学性质对支撑裂缝中煤粉运移影响的物理模拟试验,分析裂缝导流系统渗透率及煤粉产出质量浓度变化,探究不同水化学性质对支撑裂缝中煤粉运移的影响。试验结果表明:Na_(2)SO_(4)溶液驱替条件下,煤粉产出质量浓度随矿化度的增加而降低,高矿化度条件下,煤粉聚集沉降性强,堵塞裂缝通道。NaHCO_(3)溶液驱替条件下,煤粉产出质量浓度随矿化度的增加而增大,伴随矿化度的增加,水解产生OH-增加煤粉颗粒表面负电荷,增强煤粉间排斥力,缓解煤粉聚集效果,产出部分煤粉颗粒。6000 mg/L Na_(2)SO_(4)和NaHCO_(3)溶液驱替条件下流体具有更多的展布空间,渗透率最高。MgCl_(2)溶液驱替条件下,煤粉产出质量浓度随矿化度的增加而增大,高矿化度增强煤粉间相互作用,试验样内部相对平衡被打破,煤粉产出量增大,试验样内部煤粉堵塞程度大致相同,渗透率数值变化不大。在相同矿化度(10000 mg/L)条件下,不同水化学类型溶液驱替条件下煤粉产出质量浓度为:NaHCO_(3)>Na_(2)SO_(4)>MgCl_(2),试验样平均渗透率为:MgCl_(2)>NaHCO_(3)>Na_(2)SO_(4),煤粉聚集的程度,在一定程度上影响煤粉产出,Na_(2)SO_(4)和NaHCO_(3)团聚作用低于MgCl_(2),部分煤粉运移,试验样末端堵塞程度高于MgCl_(2)溶液,NaHCO_(3)水解产生OH-,煤粉处于碱性环境中,改善试验样堵塞情况,提高渗透率。根据模拟试验中渗透率波动的上升状态、下降状态和轻微波动状态3个趋势,结合实测渗透率,统计渗透率变化趋势时间段,分析煤粉产出质量浓度与煤样渗透率之间的关系,回归模型的R^(2)=0.834,说明煤粉运移影响渗透率的波动。

关键词：煤粉运移水化学类型支撑裂缝煤层气水矿化度

High-contrast imaging based on wavefront shaping to improve low signal-to-noise ratio photoacoustic signals using superpixel method

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Chinese Physics B 2020年第3期29卷 251-258页

作者：吕新晶徐新羽冯祺张彬丁迎春柳强 College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084China

Photoacoustic(PA) imaging has drawn tremendous research interest for various applications in biomedicine and experienced exponential growth over the past decade. Since the scattering effect of biological tissue on ultrasound is two-to three-orders magnitude weaker than that of light, photoacoustic imaging can effectively improve the imaging ***, as the depth of imaging further increases, the incident light is seriously affected by scattering that the generated photoacoustic signal is very weak and the signal-to-noise ratio(SNR) is quite low. Low SNR signals can reduce imaging quality and even cause imaging failure. In this paper, we proposed a new wavefront shaping and imaging method of low SNR photoacoustic signal using digital micromirror device(DMD) based superpixel method. We combined the superpixel method with DMD to modulate the phase and amplitude of the incident light, and the genetic algorithm(GA) was used as the wavefront shaping algorithm. The enhancement of the photoacoustic signal reached 10.46. Then we performed scanning imaging by moving the absorber with the translation stage. A clear image with contrast of 8.57 was obtained while imaging with original photoacoustic signals could not be achieved. The proposed method opens new perspectives for imaging with weak photoacoustic signals.

关键词： photoacoustic imaging wavefront shaping superpixel method high contrast imaging