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Negative exponential behavior of image mutual information for pseudo-thermal light ghost imaging： observation, modeling, and verification

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Science Bulletin 2017年第10期62卷 717-723页

作者： Junhui Li Bin Luo Dongyue Yang longfei yin Guohua Wu Hong Guo astute Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science and Center for Quantum Information Technology Peking University Beijing 100871 China stute Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

When using the image mutual information to assess the quality of reconstructed image in pseudothermal light ghost imaging, a negative exponential behavior with respect to the measurement number is observed. Based on information theory and a few simple and verifiable assumptions, semi-quantitative model of image mutual information under varying measurement numbers is established. It is the Gaussian characteristics of the bucket detector output probability distribution that leads to this negative exponential behavior. Designed experiments verify the model.

关键词： Ghost imaging Image mutual information Information theory Image quality assessment

Cooperation of PprI and DrRRA in response to extreme ionizing radiation in Deinococcus radiodurans

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Chinese Science Bulletin 2012年第1期57卷 98-104页

作者： WANG LiangYan yin longfei XU GuangZhi LI MingFeng ZHANG Hui TIAN Bin HUA YueJin Key Laboratory of Ministry of Agriculture for Nuclear-Agricultural Sciences Institute of Nuclear-Agricultural SciencesZhejiang UniversityHangzhou 310029China Institute of Ecology Taizhou UniversityLinhai 317000China

Deinococcus radiodurans possesses extreme resistance to ionizing radiation,and has been engineered for the remediation of toxic components in radioactive *** have previously shown that PprI(also named IrrE)and DrRRA are essential for the DNA protection and repair pathways that respond to ionizing radiation stress in this ***,we investigated the combined roles of PprI and DrRRA in resistance to gamma radiation(800 Gy).The double mutant,△drRRA△pprI,was more sensitive to gamma rays than either△drRRA or△pprI single mutants,and exhibited an elevated level of intracellular protein carbonylation,an extended delay in genome reconstitution and reduced transcriptional levels of certain DNA protection and repair proteins,such as kat,sod,recA and ***,the induction of DrRRA by ionizing radiation was partially inhibited by the deletion of pprI. Taken together,these results suggest that DrRRA and PprI might have collaborative roles in the response of *** to extreme ionizing radiation.

关键词：电离辐射诱导耐辐射球菌公共政策研究所合作超氧化物歧化酶伽玛射线转录水平

Ring-like nucleoid does not play a key role in radioresistance of Deinococcus radiodurans

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Science China(Life Sciences) 2007年第4期50卷 525-529页

作者： GAO GuanJun, LU HuiMing, yin longfei & HUA YueJin Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou 310029, China 1. Institute of Nuclear-Agricultural Sciences Zhejiang University Hangzhou 310029 China

The conclusion based on transmission electron microscopy, "the tightly packed ring-like nucleoid of the Deinococcus radiodurans R1 is a key to radioresistance", has instigated lots of debates. In this study, according to the previous research of PprI’s crucial role in radioresistance of D. radiodurans, we have attempted to examine and compare the nucleoid morphology differences among wild-type D. ra-diodurans R1 strain, pprI function-deficient mutant (YR1), and pprI function-complementary strains (YR1001, YR1002, and YR1004) before and after exposure to ionizing irradiation. Fluorescence mi-croscopy images indicate: (1) the majority of nucleoid structures in radioresistant strain R1 cells ex-hibit the tightly packed ring-like morphology, while the pprI function-deficient mutant YR1 cells carrying predominate ring-like structure represent high sensitivity to irradiation; (2) as an extreme radioresistant strain similar to wild-type R1, pprI completely function-complementary strain YR1001 almost displays the loose and irregular nucleoid morphologies. On the other hand, another radioresistant pprI partly function-complementary strain YR1002’s nucleiods exhibit about 60% ring-like structure; (3) a PprI C-terminal deletion strain YR1004 consisting of approximately 60% of ring-like nucleoid is very sensi-tive to radiation. Therefore, our present experiments do not support the conclusion that the ring-like nucleoid of D. radiodurans does play a key role in radioresistance.

关键词： Deinococcus radiodurans R1 ring-like nucleoid pprI ionizing irradiation radioresistance

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宁夏盐池惠安堡地区赋铀砂岩基本特征

地质论评 2019年第S1期65卷 189-190页

作者：殷龙飞核工业二〇三研究所陕西咸阳712000

惠安堡地区位于鄂尔多斯盆地西南缘中段,大地构造背景处于鄂尔多斯盆地西缘褶断带中,在其构造相对和缓地带的侏罗统直罗组砂岩中发现了工业铀矿体。1赋矿砂岩岩石学特征1.1赋矿砂岩物质组分特征岩性以长石砂岩为主,少量岩屑长石砂岩。... 详细信息

惠安堡地区位于鄂尔多斯盆地西南缘中段,大地构造背景处于鄂尔多斯盆地西缘褶断带中,在其构造相对和缓地带的侏罗统直罗组砂岩中发现了工业铀矿体。1赋矿砂岩岩石学特征1.1赋矿砂岩物质组分特征岩性以长石砂岩为主,少量岩屑长石砂岩。砂岩碎屑以石英、长石和岩屑为主,其次为黑云母、白云母、绿泥石,少量碳屑、重矿物及自生矿物(黄铁矿和黏土矿物)。

关键词：赋铀砂岩基本特征惠安堡地区

The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

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Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun Shao longfei He Yangyang Liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials

ZIF-8作为疫苗佐剂/递送系统的应用研究

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中国生物工程杂志 2024年第7期44卷 81-88页

作者：呼高伟洪纯丽罗希尹龙飞台州学院生命科学学院、台州市生物质功能材料开发与应用重点实验室台州318000

疫苗被认为是疫病防控的有效手段之一,其主要类型包括传统灭活疫苗、弱毒疫苗以及新型蛋白、核酸和多肽疫苗等。新型疫苗的抗原成分多为生物活性物质,容易受到外界环境的影响,单独使用在体内易被代谢且免疫原性弱,必须搭配佐剂使用。不... 详细信息

疫苗被认为是疫病防控的有效手段之一,其主要类型包括传统灭活疫苗、弱毒疫苗以及新型蛋白、核酸和多肽疫苗等。新型疫苗的抗原成分多为生物活性物质,容易受到外界环境的影响,单独使用在体内易被代谢且免疫原性弱,必须搭配佐剂使用。不同类型的疫苗搭配使用的佐剂普遍存在制备过程复杂、生物安全性低、稳定性差、转染效率低等问题。因此,亟待开发一种更加安全、高效、生物相容性好以及易制备的新型疫苗佐剂/递送载体。ZIF-8(zeolitic imidazolate framework-8)是由锌离子和2-甲基咪唑结合而成的一类金属有机框架材料,具有高稳定性、高比表面积、低毒性以及高生物相容性等特点。近年来,由于ZIF-8独特的结构和优异的热稳定性,研究人员通过仿生矿化的方法使ZIF-8包封蛋白、核酸、细菌和病毒等生物活性成分,可作为疫苗新型佐剂/递送载体。概述ZIF-8作为蛋白疫苗、核酸疫苗、灭活疫苗、病毒疫苗递送载体的相关研究进展,以期为疫苗递送载体的研发提供参考。

关键词：金属有机框架材料 ZIF-8 疫苗递送系统

鄂尔多斯盆地南缘彬县地区铀成矿关键时期的古地貌特征

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地质通报 2017年第4期36卷 527-533页

作者：贺锋张字龙刘红旭李平李亚锋殷龙飞核工业北京地质研究院北京100029 中核集团铀资源勘查与评价技术重点实验室北京100029 核工业二〇三研究所陕西咸阳712000

中侏罗世为直罗组下段沉积期,辫状河道为有利的铀储层砂体,铀矿(化)体主要赋存于辫状河砂体中,受沉积古地貌控制,主要发育在低洼区。晚侏罗世、早白垩世-古新世、始新世-中新世是砂岩型铀成矿期,古地貌控制了地下古水流的流向,控制着氧... 详细信息

中侏罗世为直罗组下段沉积期,辫状河道为有利的铀储层砂体,铀矿(化)体主要赋存于辫状河砂体中,受沉积古地貌控制,主要发育在低洼区。晚侏罗世、早白垩世-古新世、始新世-中新世是砂岩型铀成矿期,古地貌控制了地下古水流的流向,控制着氧化还原带的分布和铀矿的富集:晚侏罗世铀预成矿期,古隆起区受到潜水淋滤,含铀物质向斜坡和低洼区迁移;早白垩世-古新世铀主成矿期,古地貌控制了含氧含铀水的水流方向,氧化还原带主要分布在古地貌斜坡区。

关键词：古地貌特征沉积期成矿期铀成矿

青花菜转录因子基因BoiWRKY8及其与抗病性的关系

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核农学报 2024年第4期38卷 613-621页

作者：蒋明何佳薇方宇洁尹龙飞张慧娟台州学院生命科学学院浙江椒江318000

WRKY转录因子是植物特有的一类调控蛋白,在抵御生物和非生物逆境中起着重要作用。为初步明确该基因在抗病反应中的功能,本研究在分离青花菜BoiWRKY8基因的基础上,利用生物信息学方法进行序列分析,采用实时荧光定量PCR(qRT-PCR)明确其在... 详细信息

WRKY转录因子是植物特有的一类调控蛋白,在抵御生物和非生物逆境中起着重要作用。为初步明确该基因在抗病反应中的功能,本研究在分离青花菜BoiWRKY8基因的基础上,利用生物信息学方法进行序列分析,采用实时荧光定量PCR(qRT-PCR)明确其在核盘菌、灰霉菌侵染下的表达模式,并对过量表达植株进行抗病性鉴定。结果表明,BoiWRKY8的基因组全长为3170 bp,具2个内含子,长度分别为776和1422 bp。编码区全长为972 bp,编码323个氨基酸,WRKY结构域由60个氨基酸组成,包括一个WRKYGQK序列和一个C_(2)H_(2)锌指结构C-X_(4)-C-X_(23)-H-X_(1)-H。系统发育分析结果表明,BoiWRKY8与芸薹属植物的同源序列聚为一组,支持率达100%,与野甘蓝的关系最近。qRT-PCR结果显示,BoiWRKY8受核盘菌和灰霉菌的诱导,在6和12 h时的表达量最大,为对照的3.18/2.68和3.22/2.90倍;BoiWRKY8过量表达植株对核盘菌、灰霉菌的抗性显著增强,JA/ET通路标志基因BoPDF1.2的表达量显著提高。本研究结果为后续开展青花菜抗病机理研究和分子育种奠定了基础。

关键词：青花菜表达分析核盘菌灰霉菌过量表达

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植物GRAS家族蛋白结构和功能的研究进展

分子植物育种 2019年第19期17卷 6323-6331页

作者：殷龙飞张中保于荣吴忠义首都师范大学生命科学学院北京100048 北京市农林科学院生物技术研究中心北京市农业基因资源和生物技术重点实验室北京100097

GRAS家族蛋白是一类植物所特有的转录调控因子,在多种植物中都有报道。该家族基因含特有的保守结构域,拟南芥、水稻GRAS家族进化分析结果表明该家族可分为8个亚家族:SCL、LISCL、SHR、PAT1、DELLA、SCR、LS、HAM。GRAS家族成员众多,在... 详细信息

GRAS家族蛋白是一类植物所特有的转录调控因子,在多种植物中都有报道。该家族基因含特有的保守结构域,拟南芥、水稻GRAS家族进化分析结果表明该家族可分为8个亚家族:SCL、LISCL、SHR、PAT1、DELLA、SCR、LS、HAM。GRAS家族成员众多,在植物的信号转导、根和腋芽的发育、根瘤和菌根的形成、胁迫应答、生物解毒等过程中发挥重要作用。本研究回顾了近几年研究成果,从GRAS蛋白的结构、分布、分类以及在逆境胁迫响应、信号转导、生长发育等方面的生物学功能进行综述,以期对GRAS蛋白家族进一步的研究与利用提供理论基础。

关键词： GRAS 转录因子信号转导生长发育逆境胁迫