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Occupational Radiation Exposure and Changes in Thyroid Hormones in a Cohort of Chinese Medical Radiation Workers

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Biomedical and Environmental Sciences 2021年第4期34卷 282-289页

作者： GUO qi Shan ruan Ping HUANG Wei Xu HUANG Dai Zheng qiu Jia Chu School of Public Health Guangdong Pharmaceutical UniversityGuangzhou 510310GuangdongChina Guangdong Province Engineering&Technology Research Center for Medical 3D Printer and Personalized Medicine Guangzhou 510006GuangdongChina Department of Biomedical Engineering Guangdong Pharmaceutical UniversityGuangzhou 510006GuangdongChina Guangdong Prevention and Treatment Center for Occupational Disease Guangzhou 510300GuangdongChina Department of Biomedical Engineering Guangxi Medical UniversityNanning 530021GuangxiChina

Objective This study aimed to evaluate the association between occupational radiation exposure and changes in thyroid hormone levels among medical radiation *** This retrospective cohort study included 2,946 radiation workers from 20 Guangzhou *** on general characteristics,participant radiation dosimetry,and thyroid function test results[thyroid-stimulating hormone(TSH),triiodothyronine(T3),and thyroid hormone(T4)]were extracted from dosimetry and medical *** generalized estimating equation was used to evaluate the trend of changes in thyroid hormone levels over time and was adjusted for age,gender,and *** The average annual effective dose was very low and showed a general downward *** the follow-up period,changes in T3 and T4 levels among radiation workers were-0.015[95% confidence interval(CI)-0.018 to-0.012]nmol/L per year and-2.294(95%CI-2.426 to-2.162)nmol/L per year,*** hormone levels were significantly different between males and females.T3 levels in the group of upper quartile of dose were significantly higher than in the lower quartile group(P=0.006).No significant decreased trend in thyroid hormone levels was observed with increasing average effective *** Thyroid hormone secretion might be affected even in low-dose radiation exposure environments.

关键词： Occupational radiation Thyroid function Cohort

Enhancement of the thermostability of β-1,3-1,4-glucanase by directed evolution

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1948-1955页

作者： ZHANG Xiu-yan ruan Hui mu Lin HE Guo-qing TANG Xing-jun CHEN qi-he Department of Food Science and Nutrition Zhejiang University Hangzhou 310029 China

In order to improve the thermostability of β- 1,3-1,4-glucanase, evolutionary molecular engineering was used to evolve the β-1,3-1,4-glucanase from Bacillus subtilis ZJF-1A5. The process involves random mutation by error-prone PCR and DNA shuffling followed by screening on the filter-based assay. Two mutants, EGsl and EGs2, were found to have four and five amino acid substitutions, respectively. These substitutions resulted in an increase in melting temperature from Tm=62.5℃ for the wild-type enzyme to Tm=65.5℃ for the mutant EGsl and 67.5℃ for the mutant EGs2. However, the two mutated enzymes had opposite approaches to produce reducing sugar from lichenin with either much higher （28%） for the former or much lower （21.6%） for the latter in comparison with their parental enzymes. The results demonstrate that directed evolution is an effective approach to improve the thermostability of a mesophilic enzyme.

关键词： Directed evolution Error-prone PCR DNA shuffling β- 1 3-1 4-glucanase Thermostability

A ROS-Sensitive Diselenide-Crosslinked Polymeric Nanogel for NIR Controlled Release

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Chinese Journal of Polymer Science 2023年第3期41卷 386-393,I0007页

作者： Ji-Chao Hu qi-Hua Zhang qiu-qin mu Yi-Yuan Tang Zhen Wu Guo-Jie Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Keiraku Display Technology Co. LTD.Suzhou 215614China

Here we report a novel polymeric nanogel with stable loading cargo and near-infrared(NIR) controlled release *** nanogels are crosslinked by quaternization reactions of biocompatible poly(β-amino esters) and diselenide-bonded crosslinker(DSe DCl) in *** hydrophobic cavities of the nanogels have the property of stably encapsulating the hydrophobic guest molecules,resulted from the crosslinked network *** to the redox responsiveness of the diselenide bonds on the DSe DCl crosslinker,the nanogels can respond to oxidant H_(2)O_(2) causing the disintegration of the crosslinked network structure,thus the encapsulated guest cargo molecules will be *** is noted that,upon loading the photosensitizer IR780,the nanogels can generate reactive oxygen species(ROS) under NIR irradiation to release the *** advantages of encapsulated cargo stability enhanced by chemical cross-linking and remote stimulation response performance via NIR offer great potential of nanogels for applications of cargo controlled release.

关键词： Nanogels NIR responsiveness Diselenide-crosslinked Controlled release

Hepatitis C Virus NS2 Protein Suppresses RNA Interference in Cells

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Virologica Sinica 2020年第4期35卷 436-444页

作者： Hui Zhou qi qian Ting Shu Jiuyue Xu Jing Kong Jingfang mu Yang qiu Xi Zhou State Key Laboratory of Virology College of Life SciencesWuhan UniversityWuhan 430072China State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China Center for Translational Medicine Wuhan Jinyintan HospitalWuhan 430040China University of Chinese Academy of Sciences Beijing 100049China

RNAi interference(RNAi)is an evolutionarily conserved post-transcriptional gene silencing mechanism and has been well recognized as an important antiviral immunity in *** viruses have been shown to encode viral suppressors of RNAi(VSRs)to antagonize antiviral *** C virus(HCV)is a medically important human pathogen that causes acute and chronic *** this study,we screened all the nonstructural proteins of HCV and found that HCV NS2 could suppress RNAi induced either by small hairpin RNAs(shRNAs)or small interfering RNAs(siRNAs)in mammalian ***,we demonstrated that NS2 could suppress RNAi via its direct interaction with doublestranded RNAs(dsRNAs)and siRNAs,and further identified that the cysteine 184 of NS2 is required for the RNAi suppression activity through a serial of point mutation ***,our findings uncovered that HCV NS2 can act as a VSR in vitro,thereby providing novel insights into the life cycle and virus-host interactions of HCV.

关键词： Hepatitis C virus(HCV) NS2 Antiviral RNAi Viral suppressor of RNAi(VSR)

Fine mapping and genetic analysis of resistance genes,Rsc18,against soybean mosaic virus

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Journal of Integrative Agriculture 2022年第3期21卷 644-653页

作者： LIU Sang-lin CHENG Yan-bo MA qi-bin LI mu JIANG Ze XIA qiu-ju NIAN Hai The State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources South China Agricultural UniversityGuangzhou 510642P.R.China The Key Laboratory of Plant Molecular Breeding of Guangdong Province College of AgricultureSouth China Agricultural UniversityGuangzhou 510642P.R.China Maize Research Institute Jilin Academy of Agricultural SciencesGongzhuling 130033P.R.China Beijing Genomics Institute(BGI)-Shenzhen Shenzhen 518086P.R.China

Soybean mosaic virus(SMV) affects seed quality and production of soybean(Glycine max(L.) Merr.) ***18 is one of the dominant SMV strains in South China,and accession Zhonghuang 24 displayed resistance to *** F_(1),F_(2) and 168 F_(11) recombinant inbred lines(RILs) population derived from a hybridization between Zhonghuang 24(resistant,R) and Huaxia 3(susceptible,S) were used in this *** to the segregation ratios of the F_(2) generation(3 R:1 S) and the recombinant inbred lines(RILs) population(1 R:1 S),one dominant locus may regulate the resistance to SC18 in Zhonghuang *** using composite interval mapping(CIM),Rsc18 was mapped to a 415.357-kb region on chromosome *** candidate genes,including one NBS-LRR type gene and two serine/threonine protein type genes,were identified according to the genetic annotations,which may be related to the resistance to *** q RT-PCR demonstrated that these genes were up-regulated in the R genotype compared to the *** conclusion,the findings of this research enhanced the understanding about the R genes at the Rsc18 ***,our results will provide insights for designing molecular markers to improve marker-assisted selection and developing new varieties with resistance to SC18.

关键词： soybean mosaic virus(SMV) fine mapping recombinant inbred lines(RILs) resistance gene

Construction of CoNi_(2)S_(4) nanocubes interlinked by few-layer Ti_(3)C_(2)T_(x) MXene with high performance for asymmetric supercapacitors

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Rare Metals 2022年第12期41卷 4116-4126页

作者： Ji-qiu qi Meng-Yuan Huang Chen-Ya ruan Dong-Dong Zhu Lei Zhu Fu-Xiang Wei Yan-Wei Sui qing-Kun Meng Jiangsu Province Engineering Laboratory of High Efficient Energy Storage Technology and Equipments School of Materials Science and PhysicsChina University of Mining and TechnologyXuzhou 221116China Key Laboratory of Air-Driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000China

Both MXene and zeolitic imidazolate framework(ZIF)derivatives are tend to agglomerate during the compound process,which adversely affects their electrochemical *** alleviate this phenomenon,fewlayer MXene was stripped by mechanical method,and electrostatic self-assembly with ZIF-67 in the presence of cationic ***,CoNi_(2)S_(4)/MXene composite was synthesized by the facile hydrothermal ***_(2)S_(4)well retained the cube frame structure of the ZIF-67 with the sagging outer frame and rough *** the composite,CoNi_(2)S_(4)nanocubes were interlinked by MXene nanosheets,which can effectively improve the structural stability and make full use of the active ***_(2)S_(4)/MXene composite electrode exhibits an outperforming specific capacitance(751 C·g^(-1)at 1 A·g^(-1)),far higher than that of pure CoNi2S4(600 C·g^(-1)at 1 A·g^(-1)).An asymmetric supercapacitor(CoNi_(2)S_(4)/MXene//reduced graphene oxide(RGO))assembling delivers high energy density of 33.8 Wh·kg^(-1)and excellent cycling *** study indicates the potential of MXene/ZIF derivatives in the application of supercapacitor.

关键词： Cubic frame structure Few-layer MXene ZIF-67 Asymmetric supercapacitor

“数字铁路”——21世纪我国铁路现代化建设的战略目标

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铁道学报 2000年第3期22卷 96-101页

作者：阮秋琦北方交通大学信息科学研究所北京100044

“数字铁路”是“数字地球”概念的一个子集 ,也是“数字地球”这一庞大系统工程的一个缩影。信息技术是现代化铁路的“龙头”技术 ,是铁路挖潜增效的关键。在现有铁路设施下 ,向信息技术要效率、要运能、要安全、要服务质量是一项高投... 详细信息

“数字铁路”是“数字地球”概念的一个子集 ,也是“数字地球”这一庞大系统工程的一个缩影。信息技术是现代化铁路的“龙头”技术 ,是铁路挖潜增效的关键。在现有铁路设施下 ,向信息技术要效率、要运能、要安全、要服务质量是一项高投入产出比的重要举措。因此 ,以信息技术为基础的“数字铁路”是 2 1世纪铁路现代化建设可持续发展的战略目标。本文提出数字铁路的基本概念 ,论述了其关键技术、研究的内容、现有基础及实现的可能性。说明“数字铁路”是中国铁路突破经济因素制约的必由之路。

关键词：数字地球数字铁路信息科学信息技术

基于ROI分割和相干映射的裸手字母手势识别

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通信学报 2007年第5期28卷 94-101页

作者：周航阮秋琦北京交通大学信息科学研究所北京100044

提出了实时条件下裸手单目的手部定位和跟踪算法。结合改进的差分法提出了实用的手部约束条件,从每帧图像中提取手部图像,确定感兴趣区域(ROI,region of interesting),得到较为满意的手部分割结果,再对手部图像特征进行深入分析和提取,... 详细信息

提出了实时条件下裸手单目的手部定位和跟踪算法。结合改进的差分法提出了实用的手部约束条件,从每帧图像中提取手部图像,确定感兴趣区域(ROI,region of interesting),得到较为满意的手部分割结果,再对手部图像特征进行深入分析和提取,利用改进的相干映射算法(VCM,vector coherence mapping)进行跟踪,针对手的运动增加了约束,保证了顽健性。在这个基础上,提出了时间相关的运动预测模型,满足了实时性的要求,保证前后分析结果的一致性。实验结果证明,在不同光照和复杂背景下系统有最高达99%的识别率,与已有的系统相比,性能显著提高。

关键词：手势识别相干映射感兴趣区域人机交互

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单目模糊点脊的窗口手势跟踪

铁道学报 2006年第5期28卷 46-51页

作者：周航阮秋琦北京交通大学信息科学研究所北京100044

相对于需要第三方辅助设备的系统,基于视觉的手势跟踪更方便自然。单目的手势识别跟踪可以分为手部的定位和手指的跟踪。它涉及到对颜色空间的选取,以及由点到面再回到点的分析方法。首先,从含有手的场景中检测出手,并且得到手所在的大... 详细信息

相对于需要第三方辅助设备的系统,基于视觉的手势跟踪更方便自然。单目的手势识别跟踪可以分为手部的定位和手指的跟踪。它涉及到对颜色空间的选取,以及由点到面再回到点的分析方法。首先,从含有手的场景中检测出手,并且得到手所在的大致区域,提取出手掌的中心位置作为追踪的前提。然后,应用模糊点脊模型来描述手,对于基本的伸展状态进行了分类,为语义识别打下基础。为了控制不确定环境条件的影响,提出了一种直方图匹配算法以及使用搜索窗搜索定位方法。整个试验分成手指定位和手部区域跟踪,得到的最终数据是手指的伸展方向和角度。在有限的限定条件下,系统的初始化算法能得到更多的手部特征,相对于基于神经的方法减少了训练强度,但又保持了其准确智能的特点,能够满足实时的要求。实验的目的在于尽量减少人工干预,结果证明:这种方法的可靠性和效率都有一定提高,具有研究价值。

关键词：手势识别模糊点脊窗口搜索