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A General Authentication and Key Agreement Framework for Industrial Control System

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Chinese Journal of Electronics 2024年第4期33卷 1046-1062页

作者： Shan gao Junjie CHEN Bingsheng ZHANG Kui REN Xiaohua ye Yongsheng SHEN School of Cyber Science and Technology Zhejiang University Hangzhou Global Scientific and Technological Innovation Center Zhejiang University Zhejiang Provincial Key Laboratory of Blockchain and Cyberspace Governance Hangzhou City Brain Co. Ltd

In modern industrial control systems(ICSs), when user retrieving the data stored in field device like smart sensor, there exists two main problems: one is lack of the verification for identification of user and field device;the other is that user and field device need exchange a key to encrypt sensitive data transmitted over the *** propose a comprehensive authentication and key agreement framework that enables all connected devices in an ICS to mutually authenticate each other and establish a peer-to-peer session key. The framework combines two types of protocols for authentication and session key agreement: The first one is an asymmetric cryptographic key agreement protocol based on transport layer security handshake protocol used for Internet access, while the second one is a newly designed lightweight symmetric cryptographic key agreement protocol specifically for field devices. This proposed lightweight protocol imposes very light computational load and merely employs simple operations like one-way hash function and exclusive-or(XOR) operation. In comparison to other lightweight protocols, our protocol requires the field device to perform fewer computational operations during the authentication phase. The simulation results obtained using Open SSL demonstrates that each authentication and key agreement process in the lightweight protocol requires only 0.005 ms. Our lightweight key agreement protocol satisfies several essential security features, including session key secrecy, identity anonymity, untraceability, integrity, forward secrecy, and mutual authentication. It is capable of resisting impersonation, man-in-the-middle, and replay attacks. We have employed the Gong-NeedhamYahalom(GNY) logic and automated validation of Internet security protocols and application tool to verify the security of our symmetric cryptographic key agreement protocol.

关键词： Performance evaluation Protocols Costs Industrial control Internet security Authentication Time measurement

潜入喷管背部容腔对点火初期压强振荡影响的数值研究

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固体火箭技术 2011年第4期34卷 448-452页

作者：郜冶胡伟哈尔滨工程大学航天工程系哈尔滨150001

为深入了解点火初期药柱表面的压强振荡情况,采用计算流体力学软件FLUENT对固体火箭发动机喷管堵盖打开前的点火增压过程进行了轴对称数值计算,探讨了潜入喷管背部容腔对压强振荡的影响。计算结果表明,发动机头部和背部容腔内压强振荡... 详细信息

为深入了解点火初期药柱表面的压强振荡情况,采用计算流体力学软件FLUENT对固体火箭发动机喷管堵盖打开前的点火增压过程进行了轴对称数值计算,探讨了潜入喷管背部容腔对压强振荡的影响。计算结果表明,发动机头部和背部容腔内压强振荡最为剧烈,压强峰值和升压梯度峰值随容腔体积的增加而递减。结论可为药柱裂纹的扩展研究及固体火箭发动机的潜入喷管设计提供参考。

关键词：点火冲击波潜入喷管压强振荡升压梯度

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压水堆子通道欠热沸腾数值验证及交混翼研究

原子能科学技术 2013年第12期47卷 2208-2215页

作者：李小畅郜冶哈尔滨工程大学航天与建筑工程学院黑龙江哈尔滨150001

为改善压水堆交混翼格架在欠热沸腾工况下的热工水力特性,以子通道为研究对象验证了所使用的欠热沸腾数值模型在不同工况下的有效性。基于已验证的数值模型,对含不同偏折角交混翼格架的子通道模型在不同工况下进行了两相流数值模拟,研... 详细信息

为改善压水堆交混翼格架在欠热沸腾工况下的热工水力特性,以子通道为研究对象验证了所使用的欠热沸腾数值模型在不同工况下的有效性。基于已验证的数值模型,对含不同偏折角交混翼格架的子通道模型在不同工况下进行了两相流数值模拟,研究交混翼及其偏折角对子通道中两相流动、传热及气泡分布的影响。结果表明:交混翼在增大压降的同时明显强化了冷却剂的交混、降低了近壁面气泡份额、提高了换热效率,且在一定范围内偏折角越大影响越明显。相对较高的气泡份额将导致更大的压力损失、减弱冷却剂的交混、降低传热效率。当交混翼偏折角达25°时,继续增大其偏折角对降低近壁面气泡份额和提高传热效率的作用不再明显,反而造成压降的快速增大,因此建议其偏折角在25°左右。

关键词：压水堆欠热沸腾计算流体力学交混翼偏折角

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辣木叶乙酸乙酯部位化学成分研究

中国药学杂志 2024年第2期59卷 136-141页

作者：周立鹏雒晓卫王树楷常子豪胡倩刘宇琦高晔陈尹心王保锦黄雅王朝慧崔艺彤刘越张兰珍北京中医药大学中药学院北京102488

目的研究辣木叶乙酸乙酯部位的化学成分,并初步评价其抗氧化活性。方法运用各种色谱技术对辣木叶乙酸乙酯部位的化学成分进行分离和纯化,并依据质谱、核磁共振等波谱数据鉴定化合物的结构;采用2,2-联苯基-1-苦基肼基(DPPH)和2,2′-联... 详细信息

目的研究辣木叶乙酸乙酯部位的化学成分,并初步评价其抗氧化活性。方法运用各种色谱技术对辣木叶乙酸乙酯部位的化学成分进行分离和纯化,并依据质谱、核磁共振等波谱数据鉴定化合物的结构;采用2,2-联苯基-1-苦基肼基(DPPH)和2,2′-联氮-双(3-乙基苯并噻唑啉-6-磺酸)二铵盐(ABTS)法测试各化合物的体外抗氧化活性。结果从辣木叶乙酸乙酯部位中分离得到14个化合物,分别为淫羊藿次苷B1(1)、(3S)-O-β-D-glucopyranosyl-6-[3-oxo-(2S)-butenylideny]-1,1,5-trimethylcyclohexan-(5R)-ol(2)、淫羊藿次苷B2(3)、9-hydroxy-megastigma-4,7-dien-3-one-9-O-β-D-glucopyranoside(4)、鸢尾苷元(5)、鸢尾苷(6)、鸢尾甲苷A(7)、鸢尾甲苷B(8)、5-羟基-2-羟甲基吡啶(9)、草夹竹桃苷(10)、3,4,5-三甲氧基-1-O-β-D-苯酚葡萄糖苷(11)、1-O-(4-羟甲基苯基)α-L-吡喃鼠李糖苷(12)、苄基-O-β-D-葡萄糖苷(13)以及methyl 2-[4-(α-L-rhamnopyranosyl) phenyl] acetate(14)。其中化合物6、7和8具有一定的抗氧化活性,但均弱于阳性对照维生素C的活性。结论化合物2~11为首次从辣木属植物中分离得到。

关键词：辣木叶结构鉴定异黄酮抗氧化

Dynamic shielding of bacterial outer membrane vesicles for safe and efficient chemo-immunotherapy against tumors

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Nano Research 2024年第2期17卷 836-847页

作者： Shuping Li Xin Li Jiaqi Meng Weier Bao Shuang Wang Peng ye Xiao-Dong gao Wei Wei Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of Education School of BiotechnologyJiangnan UniversityWuxi 214122China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Bacterial outer membrane vesicles(OMVs)are potent immunostimulants of regulating the tumor microenvironment(TME)for immunotherapy,and can be used to deliver ***,the severe systemic inflammatory response triggered by OMVs upon intravenous(i.v.)injection has limited their ***,we developed a safe and effective strategy by conjugating doxorubicin-loaded serum albumin(SA-DOX,AD)onto the surface of OMVs using a matrix metalloproteinase(MMP)-cleavable peptide linker(cL).This approach enabled the dynamic shielding of OMVs to reduce the systemic side effects while simultaneously enhancing the anti-tumor effects through ***,the resulting OMV-cL-AD formulation exhibited significantly enhanced accumulation at the tumor site after ***,facilitated by the SA decoration on the OMVs ***,the shield on the OMV-cL-AD was cleaved by the over-expressed MMP in the TME,leading to the release of both OMVs and *** process provided OMV-induced immunotherapy and DOX-induced chemotherapy,resulting in synergistic tumor *** conclusion,our work demonstrated the potential of OMV-cL-AD as an effective immunochemotherapy strategy that can prolong the survival time of mice without inducing side effects.

关键词： outer membrane vesicles doxorubicin tumor microenvironment immunotherapy chemotherapy

Serrated flow behavior of GH536 superalloy under different loading rates at room temperature

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Rare Metals 2024年第5期43卷 2317-2323页

作者： Wen-Xiang gao Dong Ma Li-Li Zhao Fan ye Ling Shao Su-Jun Wu School of Materials Science and Technology Beihang UniversityBeijing100091China

Serrated flow phenomenon has been widely observed among different metals due to the potential influence on their *** tensile tests of nickel-based superalloy GH536 were carried out at loading rates of 0.06,0.60,3.60,and 36.00 mm·min^(-1)at room temperature,*** tensile stress-strain curves demonstrate repetitive and discontinuous yielding behavior,namely serrated *** is observed that the stress-strain curves were dominated by type B serration,and original annealing twin boundaries(TBs)were distorted to various degrees under comparatively different lower tensile *** contrast,the TBs almost disappear,and the type B serrations become smoother and regular under the higher loading *** phenomenon can be attributed to the interactions between TBs and dislocations during tensile *** effects of the mobile and immobile dislocations illustrate the unsteady amplitude of serrations observed in stress-strain *** electron microscope images of tested pieces reveal the interaction of dislocation and TB,with dislocation tangling around the TBs.

关键词： Nickel-based superalloy Serrations Twin boundaries Deformation mechanism

Unraveling the regulatory network of flower coloration in soybean:Insights into roles of GmMYBA3 and GmMYBR1

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The Crop Journal 2024年第2期12卷 443-455页

作者： Ruifang gao Yueqing Li Yanan Wang Xiaotong Shan Siqi Yang ye Zhang Saiyu Ma Chunbao Zhang Jianchun Qin Li Wang Xiang gao College of Plant Science Jilin UniversityChangchun 130062JilinChina Key Laboratory of Molecular Epigenetics of MOE and Institute of Genetics&Cytology Northeast Normal UniversityChangchun 130024JilinChina Soybean Research Institute National Engineering Research Center for SoybeanJilin Academy of Agricultural SciencesChangchun 130033JilinChina

Anthocyanins play crucial roles in pollen protection and pollinator attraction in flowering ***,the mechanisms underlying flower color determination and whether floral anthocyanin regulators participate in other processes remain largely unresolved in soybeans(Glycine max).In this study,we investigated the genetic components and mechanisms governing anthocyanin biosynthesis in soybean *** and genetic studies have characterized two antagonistic regulators,the positive activator GmMYBA3 and the negative repressor GmMYBR1,that modulate the gene expression of anthocyanin biosynthesis in soybean *** findings revealed a regulatory interplay between GmMYBA3 and GmMYBR1 bridged by GmTT8a,highlighting the complexity of anthocyanin regulation in different soybean *** of additional soybean cultivars demonstrated the universality of GmMYBA3 and GmMYBR1 in regulating floral anthocyanin biosynthesis-related genes,with GmF3’5’H identified as a crucial determinant of white flower *** study provides a molecular mechanism underlying soybean flower color determination,paving the way for the molecular modification of soybean flowers to probably enhance their resistance to abiotic stresses and attractiveness to pollinators.

关键词： Anthocyanin Flower color determination MBW complex MYB repressor Pleiotropic regulator

A homolog of glyceraldehyde-3-phosphate dehydrogenase from Riemerella anatipestifer is an extracellular protein and exhibits biological activity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第9期15卷 776-787页

作者： Ji-ye gao Cui-lian ye Li-li ZHU Zhi-ying TIAN Zhi-bang YANG Department of Basic Medicine Chongqing Medical University Chongqing 400016 China

Riemerella anatipestifer is the causative agent of septicemia anserum exsudativa in ducks. Its pathogenesis and virulence factors are still unclear. The glycelytic enzyme, glyceraldehyde-3-phosphate dehydrogenase （GAPDH）, an anchorless and multifunctional protein on the surface of several pathogenic microorganisms, is involved in virulence and adhesion. Whether homologs of GAPDH exist, and display similar characteristics in R. anatipestifer （RaGAPDH） has not been determined. In our research, the RaGAPDH activity from various R. anatipestifer isolates was confirmed. Twenty-two gapdh genes from genornic DNA of R. anatipestifer isolates were cloned and sequenced for phylogenetic analysis. The distribution of RaGAPDH in R. anatipestifer CZ2 strain was confirmed by antisera to recombinant RaGAPDH. The ability of purified RaGAPDH to bind host proteins was analyzed by solid-phase ligandbinding assay. Results revealed that all R. anatipestifer isolates showed different levels of GAPDH activity except four strains, which contained a gapdh-like gene. The gapdh of R. anatipestifer, which is located phylogenetically in the same branch as enterohemorrhagic Escherichia coil （EHEC）, belonged to class I GAPDH, and encoded a 36.7-kDa protein. All RaGAPDH-encoding gene sequences from field isolates of R. anatipestiferdisplayed 100% homology. The RaGAPDH localized on the extracellular membrane of several R. anatipestifer strains. Further, it was released into the culture medium, and exhibited GAPDH enzyme activity. We also confirmed the binding of RaGAPDH to plasminogen and fibrinogen. These results demonstrated that GAPDH was present in R. anatipestifer, although not in all strains, and that RaGAPDH might contribute to the microorganism＇s virulence.

关键词： Riemerella anatipestifer Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) Extracellular protein

Promoter engineering enables precise metabolic regulation towards efficientβ-elemene production in Ogataea polymorpha

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Synthetic and Systems Biotechnology 2024年第2期9卷 234-241页

作者： Min ye Jiaoqi gao Jingjing Li Wei Yu Fan Bai Yongjin J.Zhou Division of Biotechnology Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian116023PR China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023PR China Dalian Key Laboratory of Energy Biotechnology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023PR China University of Chinese Academy of Sciences Beijing100049PR China

Precisely controlling gene expression is beneficial for optimizing biosynthetic pathways for improving the ***,promoters in nonconventional yeasts such as Ogataea polymorpha are always limited,which results in incompatible gene ***,we expanded the promoter library in *** based on transcriptional data,among which 13 constitutive promoters had the strengths ranging from 0–55%of PGAP,the commonly used strong constitutive promoter,and 2 were growth phase-dependent ***,2 hybrid growth phase-dependent promoters were constructed and characterized,which had 2-fold higher ***,promoter engineering was applied to precisely regulate cellular metabolism for efficient production ofβ-*** glyceraldehyde-3-phosphate dehydrogenase gene GAP was downregulated to drive more flux into pentose phosphate pathway(PPP)and then to enhance the supply of acetyl-CoA by using phosphoketolase-phosphotransacetylase(PK-PTA)*** with the phase-dependent expression of synthase module(ERG20∼LsLTC2 fusion),the highest titer of 5.24 g/L with a yield of 0.037 g/(g glucose)was achieved in strain YY150U under fed-batch fermentation in shake *** work characterized and engineered a series of promoters,that can be used to fine-tune genes for constructing efficient yeast cell factories.

关键词： Promoter library Growth phase-dependent promoters Promoter engineering Precise metabolic regulation Ogataea polymorpha