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A CRISPR/Cas9-based single-stranded DNA recombineering system for genome editing of Rhodococcus opacus PD630

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Synthetic and Systems Biotechnology 2021年第3期6卷 200-208页

作者： youxiang liang Yuwen Wei Song Jiao Huimin Yu Department of Chemical Engineering Tsinghua UniversityBeijing100084China Key Laboratory of Industrial Biocatalysis(Tsinghua University) The Ministry of EducationBeijing100084China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing100084China

Genome engineering of Rhodococcus opacus PD630,an important microorganism used for the bioconversion of lignin,is currently dependent on inefficient homologous *** a CRISPR interference procedure for gene repression has previously been developed for *** PD630,a CRISPR/Cas9 system for gene knockout has yet to be reported for the *** this study,we found that the cytotoxicity of Cas9 and the deficiency in pathways for repairing DNA double-strand breaks(DSBs)were the major causes of the failure of conventional CRISPR/Cas9 technologies in ***,even when augmented with the recombinases Che9c60 and *** successfully developed an efficient single-stranded DNA(ssDNA)recombineering system coupled with CRISPR/Cas9 counter-selection,which facilitated rapid and scarless editing of the *** genome.A two-plasmid system,comprising Cas9 driven by a weak Rhodococcus promoter Pniami,designed to prevent cytotoxicity,and a single-guide RNA(sgRNA)under the control of a strong constitutive promoter,was proven to be appropriate with respect to cleavage function.A novel recombinase,RrRecT derived from a Rhodococcus ruber prophage,was identified for the first time,which facilitated recombination of short ssDNA donors(40-80 nt)targeted to the lagging strand and enabled us to obtain a recombination efficiency up to 103-fold higher than that of endogenous ***,by incorporating RrRecT and Cas9 into a single plasmid and then co-transforming cells with sgRNA plasmids and short ssDNA donors,we efficiently achieved gene disruption and base mutation in ***,with editing efficiencies ranging from 22%to 100%.Simultaneous disruption of double genes was also confirmed,although at a lower *** effective genome editing tool will accelerate the engineering of *** metabolism.

关键词： Rhodococcus opacus CRISPR/Cas9 ssDNA recombineering Novel recombinase Genome editing

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang Dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

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排水管道视频检测生产平台设计与实现

城市勘测 2020年第6期 51-55页

作者：梁有祥福州市勘测院福建福州350108

在福州市排水管道视频检测生产过程中,存在评估作业效率低、检测报告人工编辑工作量大、信息化程度低等问题,难以满足检测单位出具检测报告和排水管道视频建库的时间需求。本文在深入调研福州市排水管网CCTV检测流程基础上,以检测视频... 详细信息

在福州市排水管道视频检测生产过程中,存在评估作业效率低、检测报告人工编辑工作量大、信息化程度低等问题,难以满足检测单位出具检测报告和排水管道视频建库的时间需求。本文在深入调研福州市排水管网CCTV检测流程基础上,以检测视频和山维软件生产的现有排水管线数据为支撑,提出了一款排水管道视频检测生产的平台设计和实现方案,详细介绍了平台的开发技术路线、数据库、主要功能和关键技术的实现思路。

关键词： CCTV 排水管道视频检测生产平台内业评估 EPS

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依靠技术创新实现船舶建造整体水平提升

船舶设计通讯 2007年第S1期 61-64页

作者：梁有祥天津新港船厂

前言我国首艘全电力推进火车渡轮"中铁渤海1号"于2006年11月投入试运营。该船作为国家重点工程"烟大"铁路轮渡项目的首制船,是我国目前技术难度最高、舒适度最佳、船舶价值最高的集火车、汽车、旅客运输为一体的客滚船。天津新港船厂(... 详细信息

前言我国首艘全电力推进火车渡轮"中铁渤海1号"于2006年11月投入试运营。该船作为国家重点工程"烟大"铁路轮渡项目的首制船,是我国目前技术难度最高、舒适度最佳、船舶价值最高的集火车、汽车、旅客运输为一体的客滚船。天津新港船厂(以下简称"船厂")首次建造如此高技术含量的船舶,遇到了前所未有的困难,但是船厂干部。

关键词：船舶建造技术创新水平提升渤海海峡电力推进系统船厂安装环发电机核心竞争力建造质量

Global existence and large-time behavior for primitive equations with the free boundary

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Science China Mathematics 2024年第10期67卷 2303-2330页

作者： Hai-liang Li Chuangchuang liang School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Academy for Multidisciplinary Studies Capital Normal UniversityBeijing 100048China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In the present paper, the primitive equations, which can be used to simulate the large-scale motion of the ocean and atmosphere, are considered in the three-dimensional domain bounded below by a fixed solid boundary and above by a free-moving boundary. The global existence and uniqueness of strong solutions are established, and the long-time convergence to the equilibrium state is shown to be either at an exponential rate for the horizontal periodic domain or at an algebraic rate for the horizontal whole space.

关键词： primitive equations the free boundary value problem global well-posedness large-time behavior

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Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： Bing FANG Fengchun LEI liang liang School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina School of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

Towards net zero carbon buildings:Accounting the building embodied carbon and life cycle-based policy design for Greater Bay Area,China

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Geoscience Frontiers 2024年第3期15卷 284-297页

作者： Hanwei liang Xin Bian liang Dong Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Research Center of Urban Sustainable Development/School of Geographical Sciences Nanjing University of Information Science&Technology(NUIST)Nanjing 210044China Department of Architecture and Civil Engineering Chalmers University of TechnologySE-41296 GothenburgSweden Shenzhen Research Institute(SRI) City University of Hong KongShenzhenChina Department of Public and International Affairs(PIA) City University of Hong Kong999077Hong Kong Special Administrative Region School of Energy and Environment(SEE) City University of Hong Kong999077Hong Kong Special Administrative RegionChina Centre for Public Affairs and Law City University of Hong Kong999077Hong Kong Special Administrative RegionChina

Carbon mitigation of buildings is critical to promote a net-zero *** international society has vigorously promoted‘‘Net Zero Carbon Buildings”across the globe,and accounting for building carbon emissions is critical to support this *** carbon,which represents carbon emissions from the entire lifecycle of the buildings,is fundamental for realizing the idea of zero ***,only limited studies have been conducted so far that take into account the city *** paper aimed to act as a first try to account for the embodied carbon emissions in buildings in 2020 for the Guangdong-Hong Kong Macao Greater Bay Area in China(GBA).We integrated remote sensing techniques such as night-time light data(NLT)and building material flows analysis to calculate and spatialize the newly generated building material stocks(MS).Based on the MS data,we further applied life cycle assessment(LCA)to assess the embodied carbon in the *** results highlighted that over 163 million tons of embodied carbon in buildings of GBA are expected to be generated,from 497 million tons of newly generated building MS in *** embodied carbon in each life cycle stage is valuable for further lifecyclebased policy designs for:(i)supporting the updating of the green building certification system with consideration of the embodied carbon;(ii)promoting the green building material application and certification;and(iii)reducing the embodied carbon intensity from compact urban planning policy,such as the urban agglomeration policies in *** goal of this paper was to shed a light on reducing carbon emissions from the perspective of the entire lifecycle and promote the development of net zero carbon buildings in China and Asia-Pacific.

关键词： Net zero carbon building Embodied carbon Life cycle assessment Life cycle-based policies Greater Bay area

Reliability Assessment of a New General Matching Composed Network

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China Communications 2024年第2期21卷 245-257页

作者： Zhengyuan liang Junbin liang Guoxuan Zhong Guangxi Key Laboratory of Multimedia Communications and Network Technology School of ComputerElectronics and InformationGuangxi UniversityNanning 530004China Jiangxi Engineering Laboratory of IoT Technologies for Crop Growth Ji’an 343000China

The reliability of a network is an important indicator for maintaining communication and ensuring its stable operation. Therefore, the assessment of reliability in underlying interconnection networks has become an increasingly important research issue. However, at present, the reliability assessment of many interconnected networks is not yet accurate,which inevitably weakens their fault tolerance and diagnostic capabilities. To improve network reliability,researchers have proposed various methods and strategies for precise assessment. This paper introduces a novel family of interconnection networks called general matching composed networks(gMCNs), which is based on the common characteristics of network topology structure. After analyzing the topological properties of gMCNs, we establish a relationship between super connectivity and conditional diagnosability of gMCNs. Furthermore, we assess the reliability of g MCNs, and determine the conditional diagnosability of many interconnection networks.

关键词： conditional diagnosability interconnection networks network reliability super connectivity

Non-interactive SM2 threshold signature scheme with identifiable abort

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Frontiers of Computer Science 2024年第1期18卷 171-185页

作者： Huiqiang liang Jianhua CHEN School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

A threshold signature is a special digital signature in which the N-signer share the private key x and can construct a valid signature for any subset of the included t-signer,but less than t-signer cannot obtain any *** the breakthrough achievements of threshold ECDSA signature and threshold Schnorr signature,the existing threshold SM2 signature is still limited to two parties or based on the honest majority setting,there is no more effective solution for the multiparty *** make the SM2 signature have more flexible application scenarios,promote the application of the SM2 signature scheme in the blockchain system and secure cryptocurrency *** paper designs a non-interactive threshold SM2signature schemebasedon partially homomorphic encryption and zero-knowledge *** the last round requires the message input,so make our scheme non-interactive,and the pre-signing process takes 2 rounds of communication to complete after the key *** allow arbitrary threshold t

关键词： SM2 signature secure multi-party computation threshold signature UC-secure dishonest majority