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Dynamic emulation based modeling and detection of polymorphic shellcode at the network level

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Science in China(Series F) 2008年第11期51卷 1883-1897页

作者： WANG LanJia DUAN HaiXin li xing Department of Electronic Engineering Tsinghua University Beijing 100084 China Network Research Center Tsinghua University Beijing 100084 China

It is a promising way to detect polymorphic shellcode using emulation method. However, previous emulation-based approaches are limited in their performance and resilience against evasions. A new enhanced emulation-based detection approach is proposed, including an automaton-based model of the dynamic behavior of polymorphic shellcode and a detection algorithm, the detection criterion of which is derived from that model and ensures high detection accuracy. The algorithm also contains several optimization techniques, highly improving the running performance and the resilience against detection evasion shellcode. We have implemented a prototype system for our approach. The advantages of our algorithm are validated by the experiments with real network data, polymorphic shellcode samples generated by available polymorphic engines and hand-crafted detection evasion shellcode.

关键词： polymorphic shellcode intrusion detection CPU emulation

亚麻LuWRI1a在旱盐胁迫响应中的功能分析

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作物学报 2024年第7期50卷 1750-1761页

作者：李闻娟王利民齐燕妮赵玮谢亚萍党照赵丽蓉李雯徐晨梦王琰张建平甘肃省农业科学院作物研究所甘肃兰州730070

AP2/ERF转录因子家族参与植物对生物和非生物胁迫响应的调控。前期我们从亚麻中克隆了一个WRINKLED1的同源基因LuWRI1a,蛋白序列分析发现,LuWRI1a包含2个AP2的DNA结合域,属于AP2/ERF转录因子家族。对LuWRI1a的顺式作用元件进行分析发现,... 详细信息

AP2/ERF转录因子家族参与植物对生物和非生物胁迫响应的调控。前期我们从亚麻中克隆了一个WRINKLED1的同源基因LuWRI1a,蛋白序列分析发现,LuWRI1a包含2个AP2的DNA结合域,属于AP2/ERF转录因子家族。对LuWRI1a的顺式作用元件进行分析发现,pLuWRI1a包含响应光、干旱、低温和激素等多个非生物胁迫应激元件。本研究以亚麻栽培品种陇亚10号和LuWRI1a过表达转基因纯合株系为试验材料,用200 mmol L^(-1)NaCl营养液和25%PEG营养液模拟盐胁迫和干旱胁迫处理。结果表明,在盐胁迫和干旱胁迫处理后,转基因植株的相对株高、主根长度、侧根数目及叶片数均升高;3种抗氧化酶的活性均显著高于对照,而MDA含量低于对照;非生物胁迫响应基因LuAREB、LuDREB、LuLEA和LuNCED的表达水平均上调。通过探究LuWRI1a在逆境胁迫下的生物学功能发现,LuWRI1a通过抵抗盐胁迫和干旱胁迫对亚麻生长的抑制,增强活性氧清除能力、减轻膜脂的氧化损伤,激活逆境胁迫响应基因的表达等途径,增强了亚麻的耐逆性。综上所述,LuWRI1a可能是一个多功能基因,它不仅参与脂肪酸合成代谢途径,还有可能参与植物非生物胁迫信号途径。本研究为亚麻耐逆品种改良提供了新的基因资源。

关键词：亚麻 LuWRI1a 盐胁迫干旱胁迫功能分析

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Methylation of phytohormones by the SABATH methyltransferases

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Chinese Science Bulletin 2010年第21期55卷 2211-2218页

作者： QU liJia li Shuang xing ShuFan National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China The National Plant Gene Research Center (Beijing) Beijing 100101 China

In plants,one of the most common modifications of secondary metabolites is methylation catalyzed by various methyltransferases. Recently,a new class of methyltransferases,the SABATH family of methyltransferases,was found to modify phytohormones and other small *** SABATH methyltransferases share little sequence similarity with other well characterized *** has 24 members of the SABATH methyltransferase genes,and a subset of them has been shown to catalyze the formation of methyl esters with phytohormones and other small *** and genetic analyses show that methylation of phytohormones plays important roles in regulating various biological processes in plants,including stress responses,leaf development,and seed maturation/*** this review,we focus on phytohormone methylation by the SABATH family methyltransferases and the implication of these modifications in plant development.

关键词：甲基化甲基转移酶激素植物生长发育次生代谢产物生理过程遗传分析应激反应

Inferential Statistics and Machine Learning Models for Short-TermWind Power Forecasting

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Energy Engineering 2022年第1期119卷 237-252页

作者： ming Zhang Hongbo li xing Deng School of Computer Science Jiangsu University of Science and TechnologyZhenjiang212003China

The inherent randomness,intermittence and volatility of wind power generation compromise the quality of the wind power system,resulting in uncertainty in the system’s optimal *** a result,it’s critical to improve power quality and assure real-time power grid scheduling and grid-connected wind farm *** statistics are utilized in this research to infer general features based on the selected information,confirming that there are differences between two forecasting categories:Forecast Category 1(0-11 h ahead)and Forecast Category 2(12-23 h ahead).In z-tests,the null hypothesis provides the corresponding quantitative *** verify the final performance of the prediction findings,five benchmark methodologies are used:Persistence model,LMNN(Multilayer Perceptron with LMlearningmethods),NARX(Nonlinear autoregressive exogenous neural networkmodel),LMRNN(RNNs with LM training methods)and LSTM(Long short-term memory neural network).Experiments using a real dataset show that the LSTM network has the highest forecasting accuracy when compared to other benchmark approaches including persistence model,LMNN,NARX network,and LMRNN,and the 23-steps forecasting accuracy has improved by 19.61%.

关键词： Wind power forecasting correlation analysis inferential statistics neural network-related approaches

Large delay tunable slow-light based on high-gain stimulated-Brillouin-scattering amplification in optical fibers

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Chinese Science Bulletin 2009年第21期54卷 3947-3952页

作者： xing liang ZHAN li XIA Yuxing Department of Physics State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao TongUniversity Shanghai 200240 China

Tunable stimulated-Brillouin-scattering (SBS)-based slow-light in optical fibers has potential applications in optical buffering in the future all-optical router commutation systems. However, due to the low SBS threshold and relatively high realistic signal power, the gain in the usual SBS systems is limited at^30 dB. This paper presents a high-gain SBS scheme to realize large delay slow-light, which benefits from avoiding the depletion of the pump power in a short fiber as SBS media. The experiment demonstrates that, up to 50 dB non-saturated gain has been observed in the single-stage 591.8 m fiber SBS amplification. The slow-light delay can be obtained 52 ns, and the fractional delay can exceed 1.

关键词：布里渊散射增益放大延迟光纤可调整流系统全光路由器信号功率

Effects of halobenzoquinone and haloacetic acid water disinfection byproducts on human neural stem cells

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Journal of Environmental Sciences 2017年第8期29卷 239-249页

作者： Katherine Z.Fu Jinhua li Sai Vemula Birget Moe xing-Fang li Division of Analytical&Environmental Toxicology Department of Laboratory Medicine&PathologyFaculty of Medicine&DentistryUniversity of Alberta Alberta Centre for Toxicology Department of Physiology&PharmacologyFaculty of MedicineUniversity of Calgary

Human neural stem cells（h NSCs） are a useful tool to assess the developmental effects of various environmental contaminants; however, the application of h NSCs to evaluate water disinfection byproducts（DBPs） is scarce. Comprehensive toxicological results are essential to the prioritization of DBPs for further testing and regulation. Therefore, this study examines the effects of DBPs on the proliferation and differentiation of h NSCs. Prior to DBP treatment, characteristic protein markers of h NSCs from passages 3 to 6 were carefully examined and it was determined that h NSCs passaged 3 or 4 times maintained stem cell characteristics and can be used for DBP analysis. Two regulated DBPs, monobromoacetic acid（BAA） and monochloroacetic acid（CAA）, and two emerging DBPs, 2,6-dibromo-1,4-benzoquinone（2,6-DBBQ） and 2,6-dichloro-1,4-benzoquinone（2,6-DCBQ）, were chosen for h NSC treatment. Both 2,6-DBBQ and 2,6-DCBQ induced cell cycle arrest at S-phase at concentrations up to 1 μmol/L. Comparatively, BAA and CAA at 0.5 μmol/L affected neural differentiation. These results suggest DBP-dependent effects on h NSC proliferation and differentiation. The DBP-induced cell cycle arrest and inhibition of normal h NSC differentiation demonstrate the need to assess the developmental neurotoxicity of DBPs.

关键词： Disinfection byproducts Human neural stem cells Differentiation Halobenzoquinones Haloacetic acids Cell cycle arrest

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计及磨损的电连接器插拔力分析

固体力学学报 2024年第1期45卷 52-60页

作者：李友华沈飞王志慧刘奕光邢前柯燎亮天津大学机械工程学院天津300350 中国航天标准化与产品保证研究院北京100071

电连接器在工程中使用量大,接触失效情况严重,一旦发生失效则有可能影响设备的正常使用甚至毁坏设备.针对电连接器接触失效占比率较高,且磨损对插拔力的影响规律未知等问题,本文以国产某型号电连接器为研究对象,建立电连接器的等效有限... 详细信息

电连接器在工程中使用量大,接触失效情况严重,一旦发生失效则有可能影响设备的正常使用甚至毁坏设备.针对电连接器接触失效占比率较高,且磨损对插拔力的影响规律未知等问题,本文以国产某型号电连接器为研究对象,建立电连接器的等效有限元模型,使用自适应网格技术和耗散能磨损模型进行磨损模拟,获得不同插拔次数下接触表面的磨损形貌,讨论不同插拔次数下磨损程度对电连接器插拔力的影响.结果表明,随着插拔次数的增加,电连接器表面的磨损会逐渐严重,插拔力的波动现象也会更加明显,且磨损对电连接器的拔出力影响较插入力更明显.

关键词：电连接器磨损分析插拔力有限元模型自适应网格

以局灶节段硬化性肾小球肾炎为病理特点的Donnai-Barrow综合征1例并文献复习

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罕少疾病杂志 2024年第4期31卷 1-3,6页

作者：马岩刘静罗丹杨星星韦性娇梁丽俊宁夏医科大学临床医学院宁夏银川750004 宁夏医科大学总医院儿科宁夏银川750000

目的探讨儿童Donnai-Barrow综合征(Donnai Barrow syndrome,DBS)患者的临床特点及病理类型。方法回顾性分析2022年4月就诊于宁夏医科大学总医院儿科的1例Donnai-Barrow综合征患儿的临床资料,并分别以“Donnai Barrow”、“FOAR”为检索... 详细信息

目的探讨儿童Donnai-Barrow综合征(Donnai Barrow syndrome,DBS)患者的临床特点及病理类型。方法回顾性分析2022年4月就诊于宁夏医科大学总医院儿科的1例Donnai-Barrow综合征患儿的临床资料,并分别以“Donnai Barrow”、“FOAR”为检索词检索中国知网、万方数据库、PubMed数据库自建库至2022年5月的相关文献。结合本病例及其他已报道的受累者,总结DBS的临床特点、诊疗经过及可能预后。结果患儿,女,13岁11月,因“发现蛋白尿13年余”就诊于宁夏医科大学总医院儿科,完善基因检测后确诊为DBS,结合肾活检病理结果诊断为“慢性肾小球肾炎局灶节段硬化性肾小球肾炎(NOS型)”。总结目前已报道的74例DBS患者中有36.49%的受累者存在蛋白尿,其中3例完善肾脏穿刺后病理结果提示肾小球硬化。结论绝大多数DBS患者主要肾脏异常表现为蛋白尿,尽早完善肾穿刺活检对于明确DBS肾脏损害性质,提早预防肾衰竭、避免相关并发症具有指导意义。

关键词： Donnai-Barrow综合征局灶节段硬化性肾小球肾炎儿童

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稀有白甲鱼人工繁殖与胚胎发育

中国水产科学 2024年第6期31卷 662-673页

作者：韩淋梅刘明求李传武向兴李建成肖亚梅邹利田璐谢仲桂梁志强湖南省水产科学研究所湖南师范大学生命科学学院省部共建淡水鱼类发育生物学国家重点实验室怀化市洪江区畜牧水产事务中心怀化天鲮自然保护有限公司

为实现稀有白甲鱼（Onychostoma rara）的人工繁殖,丰富稀有白甲鱼胚胎发育的生物学资料，2016—2019年从怀化市沅江水系捕捞野生稀有白甲鱼12批次,放入网箱中进行驯化养殖,获得性腺发育成熟的稀有白甲鱼亲本,2019年人工繁殖获得成功,... 详细信息

为实现稀有白甲鱼（Onychostoma rara）的人工繁殖,丰富稀有白甲鱼胚胎发育的生物学资料，2016—2019年从怀化市沅江水系捕捞野生稀有白甲鱼12批次,放入网箱中进行驯化养殖,获得性腺发育成熟的稀有白甲鱼亲本,2019年人工繁殖获得成功,繁育苗种8500尾;2023年,子一代苗种性腺发育成熟,获得全人工繁殖成功,繁殖苗种20.2万尾。雌鱼适宜催产药物组合和剂量为:LHRH-A212μg/kg+HCG 700 IU/kg+PG 1.5 mg/kg,分两次注射,雄鱼剂量减半。采用干法受精,显微镜下观察并记录受精卵的时序及发育特征。稀有白甲鱼受精卵颜色为黄色,沉性卵,具有微黏性,受精30min后黏性消失,卵径为（2.21±0.06）mm,吸水膨胀后卵径为（2.88±0.07）mm。水温为19.5～25.5℃时,稀有白甲鱼胚胎孵化时长约为45.5 h,孵化累积积温为1024.39 h·℃。初孵鱼苗呈淡黄色，全身无其他色素,孵化后第2天,眼球黑色素沉着,心脏及腹部红色血管清晰可见。当孵化温度降低,胚胎出膜的时间延长,出膜前期眼球色素明显,心脏及腹部可见红色血液流动,表现出更完善的发育状态。本研究首次实现了稀有白甲鱼的人工繁殖,并对其胚胎发育的时序及发育特征进行了较为系统的观察,为稀有白甲鱼野生种群恢复及规模化产业开发提供了苗种,也为我国土著鱼类繁育提供了重要参考资料。

关键词：稀有白甲鱼人工繁殖胚胎发育