检索结果-南通市图书馆

Quantitative characterization of filamentous fungal promoters on a single-cell resolution to discover cryptic natural products

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2023年第4期66卷 848-860页

作者： Peng-Lin Wei Jie Fan Jingwen Yu Zihui Ma Xian Guo Nancy PKeller erwei Li Chunbo Lou Wen-Bing yin State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China Department of Medical Microbiology and Immunology University of Wisconsin-MadisonMadisonWI 53706USA CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods.Here we established a method for quantitative assessment of filamentous fungal promoters based on flow cytometry detection of the superfolder green fluorescent protein at single-cell resolution.Using this quantitative method,we acquired a library of 93 native promoter elements from Aspergillus nidulans in a high-throughput format.The strengths of identified promoters covered a 37-fold range by flow cytometry.P_(zipA) and P_(sltA)were identified as the strongest promoters,which were 2.9-and 1.5-fold higher than that of the commonly used constitutive promoter P_(gpdA).Thus,we applied P_(zipA)and P_(sltA)to activate the silent nonribosomal peptide synthetase gene Afpes1 from Aspergillus fumigatus in its native host and the heterologous host A.nidulans.The metabolic products of Afpes1 were identified as new cyclic tetrapeptide derivatives,namely,fumiganins A and B.Our method provides an innovative strategy for natural product discovery in fungi.

关键词： fungal promoter quantitative characterization single-cell resolution cryptic natural product activation of silent gene cluster

在线全文

学校读者我要写书评

暂无评论

基于药性理论的中药抗辐射预测模型的构建

中草药 2024年第8期55卷 2684-2693页

作者：杨淇郝二伟侯小涛邓家刚杜正彩范丽丽夏中尚广西中医药大学药学院广西南宁530000 广西中医药大学广西中药药效研究重点实验室广西南宁530000 广西中医药大学广西农作物废弃物功能成分研究协同创新中心广西南宁530000 广西中医药大学广西中医湿病方药理论与转化重点实验室广西南宁530000 广西中医药大学广西中医药科学实验中心广西南宁530000

目的以中药药性作为特征描述符构建机器学习抗辐射作用预测模型,并解释抗辐射中药药性的重要药性特征以指导临床和日常辐射防治。方法通过药智网、中国知网、PubMed等数据库获取报道具有抗辐射作用的中药研究文献,通过SymMap数据库获得... 详细信息

目的以中药药性作为特征描述符构建机器学习抗辐射作用预测模型,并解释抗辐射中药药性的重要药性特征以指导临床和日常辐射防治。方法通过药智网、中国知网、PubMed等数据库获取报道具有抗辐射作用的中药研究文献,通过SymMap数据库获得《中国药典》等权威著作记载的中药性味归经等药性作为特征描述符构建数据库,并将数据处理为适合机器学习的格式。使用随机森林、支持向量机、梯度提升、逻辑回归、全连接神经网络5种机器学习模型对数据集进行五折交叉训练并进行性能评估,再使用10个未参与训练的报道具抗辐射作用的中药和10个报道无抗辐射作用的中药作为外部验证集测试模型,最后利用SHapley加性解释(SHapley additive ex planations,SHAP)解释器对决定抗辐射作用有无的重要药性特征进行可视化。结果收集到涉及单味药研究、保健食品注册和复方研究共136味报道具抗辐射作用的中药,总频次为447次,其中中药使用频次及频率排名前3的为灵芝、红景天、枸杞子,频次≥10的中药共10味。在5个机器学习的性能评估中,随机森林性能最佳,其准确率、平衡F分数(F1)和曲线下面积(area under urve,AUC)分别为0.8044、0.7732和0.8798。在外部中药抗辐射的验证中,随机森林模型能较好地预测已报道具有抗辐射作用的中药。性能最佳的随机森林SHAP解释器认为“补虚、清热”功效,“心、肝、脾、肺”归经,“酸、甘、苦”味,“寒”药性特征对抗辐射作用贡献最大。结论首次将中药药性作为特征描述应用到机器学习当中并取得了较好的预测模型性能,并指导了放射病的中医药防治,即当以扶正祛邪,滋阴降火,主治心、肝、脾、肺为治疗原则。此外,机器学习模型较好的预测结果反映了中医药理论对疾病的防治具有良好的可解释性与可重现性。

关键词：机器学习中药药性四气五味抗辐射灵芝红景天枸杞子

在线全文

学校读者我要写书评

暂无评论

面向情感计算的视频诱发范式的回顾与思考

智能安全

智能安全 2024年第1期3卷 49-61页

作者：王筱敏赵少楷许敏鹏谢良闫野印二威天津大学医学工程与转化医学研究院天津300072 军事科学院国防科技创新研究院北京100071

情感计算的一个重要目的是建立一个能够对人类情绪进行实时、准确判别的智能系统,以提高人机交互的和谐性,具有广泛的应用前景。在实验室条件下诱发情感需要借助情绪诱发范式(Experimental Paradigm for Inducing Emotions,EPIE)。近年... 详细信息

情感计算的一个重要目的是建立一个能够对人类情绪进行实时、准确判别的智能系统,以提高人机交互的和谐性,具有广泛的应用前景。在实验室条件下诱发情感需要借助情绪诱发范式(Experimental Paradigm for Inducing Emotions,EPIE)。近年来,基于视频的情绪诱发范式获得了大量的关注。然而,少有文献系统性地总结面向情感计算的视频诱发范式中的实验流程和统计方法,以及对实验标准和规范开展梳理和介绍。根据近年来已报道的情感计算的研究成果,回顾了它们所采用的情绪诱发范式,包含情绪模型选择、刺激素材筛选、被试筛选和培训、评价问卷的设计与统计方法、实验流程设计。此外,在总结和评价现有范式的基础之上,对面向情感计算的视频诱发范式的被试选择、素材顺序、自评问卷等提出了新的思路和建议。

关键词：情感计算情绪诱发范式视频诱发情绪

Recent advances in wireless epicortical and intracortical neuronal recording systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2022年第4期65卷 5-22页

作者： Bowen JI Zekai LIANG Xichen YUAN Honglai XU Minghao WANG erwei yin Zhejun GUO Longchun WANG Yuhao ZHOU Huicheng FENG Honglong CHANG Jingquan LIU Unmanned System Research Institute Northwestern Polytechnical University Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical University Collaborative Innovation Center of Northwestern Polytechnical University NEURACLE TECH (China) Co. Ltd. College of Electronics and Information Hangzhou Dianzi University Defense Innovation Institute Academy of Military Sciences (AMS) Tianjin Artificial Intelligence Innovation Center (TAIIC) National Key Laboratory of Science and Technology on Micro/Nano Fabrication Department of Micro/Nano ElectronicsShanghai Jiao Tong University

An implantable brain-computer interface(BCI) has proven to be effective in the field of sensory and motor function restoration and in the treatment of neurological disorders. Using a BCI recording system,we can transform current methods of human interaction with machines and the environment, especially to help those with cognitive and mobility disabilities regain mobility and reintegrate into society. However,most reported work has focused on a simple aspect of the whole system, such as electrodes, circuits, or data transmission, and only a very small percentage of systems are wireless. A miniature, lightweight, wireless,implantable microsystem is key to realizing long-term, real-time, and stable monitoring on freely moving animals or humans in their natural conditions. Here, we summarize typical wireless recording systems, from recording electrodes, processing chips and controllers, wireless data transmission, and power supply to the system-level package for either epicortical electrocorticogram(ECo G) or intracortical local field potentials(LFPs)/spike acquisition, developed in recent years. Finally, we conclude with our vision of challenges in next-generation wireless neuronal recording systems for chronic and safe applications.

关键词： wireless implant neuronal recording system recording electrodes processing chips wireless data transmission power supply system-level package

Human 8-cell embryos enable efficient induction of disease-preventive mutations without off-target effect by cytosine base editor

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Protein & Cell 2023年第6期14卷 416-432页

作者： yinghui Wei Meiling Zhang Jing Hu yingsi Zhou Mingxing Xue Jianhang yin Yuanhua Liu Hu Feng Ling Zhou Zhifang Li Dongshuang Wang Zhiguo Zhang yin Zhou Hongbin Liu Ning Yao erwei Zuo Jiazhi Hu Yanzhi Du Wen Li Chunlong Xu Hui Yang Center for Reproductive Medicine International Peace Maternity and Child Health HospitalInnovative Research Team of High-level Local Universities in ShanghaiSchool of MedicineShanghai Jiao Tong UniversityShanghai 2000301.Center for Reproductive MedicineInternational Peace Maternity and Child Health HospitalInnovative Research Team of High-level Local Universities in ShanghaiSchool of MedicineShanghai Jiao Tong UniversityShanghai 200030China Institute of Neuroscience State Key Laboratory of NeuroscienceKey Laboratory of Primate NeurobiologyCAS Center for Excellence in Brain Science and Intelligence TechnologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China Lingang Laboratory Shanghai Research Center for Brain Science and Brain-Inspired Intelligence TechnologyShanghai 200031China Center for Reproductive Medicine Ren Ji HospitalSchool of MedicineShanghai Key Laboratory for Assisted Reproduction and Reproductive GeneticsShanghai Jiao Tong UniversityShanghai 200127China The MOE Key Laboratory of Cell Proliferation and Differentiation School of Life SciencesGenome Editing Research CenterPeking UniversityBeijing 100871China Center for Reproductive Medicine Shandong UniversityJinan 250012China Center for Reproductive Medicine Anhui Provincial Maternal and Child Health HospitalHefei 230001China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518000China Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefei 230022China

Approximately 140 million people worldwide are homozygous carriers of APOE4(ε4),a strong genetic risk factor for late onset familial and sporadic Alzheimer’s disease(AD),91%of whom will develop AD at earlier age than heterozygous carriers and noncarriers.Susceptibility to AD could be reduced by targeted editing of APOE4,but a technical basis for controlling the off-target effects of base editors is necessary to develop low-risk personalized gene therapies.Here,we first screened eight cytosine base editor variants at four injection stages(from 1-to 8-cell stage),and found that FNLS-YE1 variant in 8-cell embryos achieved the comparable base conversion rate(up to 100%)with the lowest bystander effects.In particular,80%of AD-susceptibleε4 allele copies were converted to the AD-neutralε3 allele in humanε4-carrying embryos.Stringent control measures combined with targeted deep sequencing,whole genome sequencing,and RNA sequencing showed no DNA or RNA off-target events in FNLS-YE1-treated human embryos or their derived stem cells.Furthermore,base editing with FNLS-YE1 showed no effects on embryo development to the blastocyst stage.Finally,we also demonstrated FNLS-YE1 could introduce known protective variants in human embryos to potentially reduce human susceptivity to systemic lupus erythematosus and familial hypercholesterolemia.Our study therefore suggests that base editing with FNLS-YE1 can efficiently and safely introduce known preventive variants in 8-cell human embryos,a potential approach for reducing human susceptibility to AD or other genetic diseases.

关键词： human embryo APOE4 disease-preventive mutations base editor

Growth habit of polar crystals

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第18期45卷 1662-1666页

作者： Wenjun Li erwei Shi Zhizhan Chen Zhiwen yin Acad Sinica Shanghai Inst Ceram Shanghai 201800 Peoples R China

Using coordination polyhedron rule, growth habit of polar crystals such as ZnO, ZnS and SiO2 is investigated. It shows that the growth rates in the positive and negative polar axis directions are different. The theoretical growth habit of ZnO crystal is hexagonal prism and the growth rates of its various faces are: V{0001} >V{0111} > V{0110} > V{0111} > V{0001}. The growth habit of ZnScrystal is tetrahedron and its growth rates of different crystal faces are: V(111}>V{001}>V(001}=V{100} = V{010}>V{111}. The growth rate relationship between positive and negative polar axis directionsof SiO2 crystal is V{1120} > V{1120}. These results are in agreement with the growth habits observedunder hydrothermal conditions. The different growth rates between positive and negative polar axis directions cannot be explained by PBC theory.

关键词： ZnO crystal ZnS crystal SiO2 crystal growth habit.

在线全文

学校读者我要写书评

暂无评论

基于多任务辅助推理的近眼视线估计方法

北京航空航天大学学报 2022年第6期48卷 1030-1037页

作者：王小东谢良闫慧炯闫野印二威李卫国北京航空航天大学软件学院北京100083 天津(滨海)人工智能创新中心天津300450 军事科学院国防科技创新研究院北京100071

眼动交互是头戴式虚拟现实(VR)/增强现实(AR)设备的关键操控方式,如何进行高精度、高鲁棒性的非标定视线估计是当前VR/AR眼动交互的核心问题之一,高效、鲁棒的非标定视线估计需要大量的眼图训练数据和高效的算法结构做支撑。在现有基于... 详细信息

眼动交互是头戴式虚拟现实(VR)/增强现实(AR)设备的关键操控方式,如何进行高精度、高鲁棒性的非标定视线估计是当前VR/AR眼动交互的核心问题之一,高效、鲁棒的非标定视线估计需要大量的眼图训练数据和高效的算法结构做支撑。在现有基于深度学习的近眼视线估计方法的基础上,通过添加多任务辅助推理模块,增加网络结构的多阶段输出,进行多任务联合训练,在不增加视线估计测试耗时的前提下,有效提升视线估计精度。在模型训练时,从视线估计网络结构的多个中间阶段引出多个眼部特征的辅助推理并行网络头,包括眼动图像的语义分割、虹膜边界框及眼部轮廓信息,为原始视线估计网络提供多阶段中继监控,在不增加训练数据的基础上,有效提升视线估计网络的测试精度。在国际公开数据集Acomo-14与OpenEDS2020上的验证实验表明,与无辅助推理的网络相比,所提方法精度分别得到了21.74%与18.91%的效果提升,平均角度误差分别减少到1.38°与2.01°。

关键词：视线估计增强现实(AR) 人机交互多任务学习辅助推理

在线全文

学校读者我要写书评

暂无评论

我国乡村旅游社区演化历程和发展趋势研究

安顺学院学报 2023年第6期25卷 22-26页

作者：尹科严尔玮安顺学院政法学院安顺学院外国语学院贵州安顺561000

乡村旅游社区具有人口聚集、产业发展和社会稳定的基础性地位和作用,一直都是世界乡村可持续发展的重要议题。20世纪50年代至今,我国乡村旅游社区历经复杂发展历程。科学总结该发展历程,可以促进我国乡村旅游及其社区发展和转型。我国... 详细信息

乡村旅游社区具有人口聚集、产业发展和社会稳定的基础性地位和作用,一直都是世界乡村可持续发展的重要议题。20世纪50年代至今,我国乡村旅游社区历经复杂发展历程。科学总结该发展历程,可以促进我国乡村旅游及其社区发展和转型。我国城市社区长期引领农村社区发展,农村社区发展又衍生出乡村旅游社区,三者之间既有承接又有演化。结合我国城市社区建设和农村社区发展实际,借鉴Butler旅游地生命周期理论,将我国乡村旅游社区演化过程划分为萌芽、确立、初步发展、全面发展和新时代深化改革五个阶段,并对五个阶段中发生的代表性事件进行阐述,进而分析其未来发展社区主体人本化、产业融合化、战略协同化和基础设施建设绿色生态化等趋势,对丰富和完善我国乡村旅游社区可持续发展理论具有重要价值。

关键词：旅游目的地乡村旅游社区演化历程

增强现实场景下基于稳态视觉诱发电位的机械臂控制系统

在线全文

学校读者我要写书评

暂无评论

电子与信息学报 2022年第2期44卷 496-506页

作者：陈玲玲陈鹏飞谢良许敏鹏徐登科闫慧炯罗治国闫野印二威河北工业大学人工智能与数据科学学院天津300130 智能康复装置与检测技术教育部工程研究中心天津300130 军事科学院国防科技创新研究院北京100071 天津(滨海)人工智能创新中心天津300450 天津大学天津300072 中国铁道科学研究院通信信号研究所北京100081

目前脑控机械臂在医疗康复等多个领域展现出了宽广的应用前景,但也存在灵活性较差、使用者易疲劳等不足之处。针对上述不足,该文设计一套增强现实(AR)环境下基于稳态视觉诱发电位(SSVEP)的机械臂异步控制系统。利用滤波器组典型相关分... 详细信息

目前脑控机械臂在医疗康复等多个领域展现出了宽广的应用前景,但也存在灵活性较差、使用者易疲劳等不足之处。针对上述不足,该文设计一套增强现实(AR)环境下基于稳态视觉诱发电位(SSVEP)的机械臂异步控制系统。利用滤波器组典型相关分析方法(FBCCA)实现对12个目标的识别;提出基于投票策略和差值预测的动态窗口,实现刺激时长的自适应调节;利用伪密钥实现机械臂异步控制,完成拼图任务。试验结果表明,动态窗口可以根据受试者状态自动调整刺激时长,离线平均准确度为(93.11±5.85)%,平均信息传输速率(ITR)为(59.69±8.11)bit·min^(–1)。在线单次命令平均选择时间为2.18 s,有效地减轻受试者的视觉疲劳。每位受试者均能迅速完成拼图任务,证明了该人机交互方法的可行性。

关键词：脑机接口机械臂增强现实动态窗口异步控制