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Heterogeneous distribution of Cardinium in whitefly populations is associated with host nuclear genetic background

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Insect Science 2023年第6期30卷 1701-1712页

作者： hongran li Ying liu Xiaoying Wei Huipeng Pan Youjun Zhang Xuguo Zhou Dong Chu Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management College of Plant Health and MedicineQingdao Agricultural UniversityQingdaoShangdong ProvinceChina Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureKey Laboratory of Gene Editing Technologies(Hainan)Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong ProvinceChina Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province South China Agricultural UniversityGuangzhouChina Department of Plant Protection Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina Department of Entomology University of KentuckyLexingtonKentuckyUSA

Inherited bacterial symbionts are very common in arthropods, but infection frequency can vary widely among populations. Experiments and interpopulation comparisons suggest that host genetic background might be important in explaining this variation. Our extensive field investigation showed that the infection pattern of the facultative symbiont Cardinium was heterogeneous across geographical populations of the invasive whitefly Bemisia tabaci Mediterranean (MED) in China, with genetic nuclear differences evident in 2 of the populations: 1 with a low infection rate (SD line) and 1 with a high infection rate (HaN line). However, whether the heterogeneous frequency of Cardinium is associated with the host genetic background remains poorly understood. Here, we compared the fitness of the Cardinium-infected and uninfected sublines with similar nuclear genetic backgrounds from SD and HaN lines, respectively, and further determine whether host extranuclear or nuclear genotype influenced the Cardinium–host phenotype by performing 2 new introgression series of 6 generations between SD and HaN lines (i.e., Cardinium-infected females of SD were backcrossed with uninfected males of HaN, and vice versa). The results showed that Cardinium provides marginal fitness benefits in the SD line, whereas Cardinium provides strong fitness benefits in the HaN line. Further, both Cardinium and the Cardinium–host nuclear interaction influence the fecundity and pre-adult survival rate of B. tabaci, whereas the extranuclear genotype does not. In conclusion, our results provide evidence that Cardinium-mediated fitness effects were closely associated with the host genetic background, which provides a fundamental basis for understanding the mechanism underlying the heterogeneous distribution of Cardinium in B. tabaci MED populations across China.

关键词： Bemisia tabaci Cardinium heterogeneity infection frequency nuclear genotype

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碳素钢铸坯表面横裂纹原因分析与控制

河南冶金 2024年第1期32卷 37-39页

作者：邓宗厅王向松李洪燃卞鸿涛段大祎李孟华安阳钢铁股份有限公司河南安阳455004

某炼轧厂碳素钢因生产工艺控制及过程参数使用不当,造成轧后表面翘皮、舌头状及指甲状结疤缺陷突出。通过去除铸坯表面氧化铁皮、边部酸蚀等方式检查轧后缺陷批次表面质量,发现铸坯表面横裂纹、角部横裂纹是造成该缺陷的主要原因。通过... 详细信息

某炼轧厂碳素钢因生产工艺控制及过程参数使用不当,造成轧后表面翘皮、舌头状及指甲状结疤缺陷突出。通过去除铸坯表面氧化铁皮、边部酸蚀等方式检查轧后缺陷批次表面质量,发现铸坯表面横裂纹、角部横裂纹是造成该缺陷的主要原因。通过对该系列钢种工艺C含量、生产过程结晶器振动参数及扇形段二次冷却水强度进行优化,达到减少铸坯表面横裂纹及角部裂纹的目的,从而降低铸坯轧后结疤率。

关键词：表面横裂纹轧后缺陷冷却水强度

Thymic epithelial cell development and differentiation: cellular and molecular regulation

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Protein & Cell 2013年第5期4卷 342-355页

作者： lina Sun Haiying Luo hongran li Yong Zhao State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of ZoologyChinese Academy of SciencesBeijing 100101China

Thymic epithelial cells (TECs) are one of the most important components in thymic microenvironment supporting thymocyte development and maturation. TECs, composed of cortical and medullary TECs, are derived from a common bipotent progenitor, mediating thymocyte positive and negative selections. Multiple levels of signals including intracellular signaling networks and cell-cell interaction are required for TEC development and differentiation. Transcription factors Foxn1 and autoimmune regulator (Aire) are powerful regulators promoting TEC development and differentiation. Crosstalks with thymocytes and other stromal cells for extrinsic signals like RANKL, CD40L, lymphotoxin, fibroblast growth factor (FGF) and Wnt are also definitely required to establish a functional thymic microenvironment. In this review, we will summarize our current understanding about TEC development and differentiation, and its underlying multiple signal pathways.

关键词： thymus thymic epithelial cells Aire Foxn1 TNFR NF-κB FGFs

海鲈鱼酸性磷酸酶分离纯化及其抑制剂虚拟筛选

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食品科学技术学报 2023年第5期41卷 144-152页

作者：李园园魏天雨丁悦艳李红燃师丹华李颖畅李学鹏渤海大学食品科学与工程学院/生鲜农产品贮藏加工及安全控制技术国家地方联合工程研究中心辽宁锦州121013

为延缓海水鱼类肌苷酸降解,保留鱼类本身的鲜味成分,以新鲜的海鲈鱼为研究对象,经NaAc-HAc缓冲液(pH值为5.0)提取,饱和硫酸铵分级沉淀、阴离子交换柱和葡聚糖凝胶柱分离纯化后,研究海鲈鱼肝中酸性磷酸酶(acid phosphatase,ACP)的酶学特... 详细信息

为延缓海水鱼类肌苷酸降解,保留鱼类本身的鲜味成分,以新鲜的海鲈鱼为研究对象,经NaAc-HAc缓冲液(pH值为5.0)提取,饱和硫酸铵分级沉淀、阴离子交换柱和葡聚糖凝胶柱分离纯化后,研究海鲈鱼肝中酸性磷酸酶(acid phosphatase,ACP)的酶学特性,采用虚拟筛选和分子对接技术筛选潜在的天然ACP抑制剂。结果表明:分离纯化出ACPⅠ和ACPⅡ2种同工酶;ACPⅠ的比活力为6.57 U/mg,纯化了36.50倍,回收率为9.96%;ACPⅡ的比活力为4.62 U/mg,纯化了25.69倍,回收率为6.07%。对回收率和纯化倍数相对较高的ACPⅠ进一步研究,发现其K_(m)为3.174 mmol/L,v_(max)为0.982μmol/(L·min)。ACPⅠ最适温度为30℃,最适pH值为5.0。ACPⅠ的二级结构中α-螺旋含量为14.10%,β-折叠含量为35.90%,β-转角含量为18.20%,无规则卷曲含量为32.60%。虚拟筛选出5个多酚类化合物可作为ACP抑制剂,与ACP相互作用方式主要是氢键和疏水作用。在一定浓度范围内(0~1 mmol/L),5个多酚类化合物均能有效抑制ACP活性,浓度越大抑制效果越好。研究旨在为贮藏过程中水产品的风味和品质控制提供理论依据。

关键词：海鲈鱼酸性磷酸酶分离纯化圆二色谱虚拟筛选多酚化合物

虚假数据注入攻击下线性系统的非模型预测控制

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江苏海洋大学学报（自然科学版） 2022年第2期31卷 72-77页

作者：张泽禹李宏然江苏海洋大学计算机工程学院江苏连云港222005

水下机器人在海洋勘探中起着至关重要的作用,其以高机动性和线性控制系统的简易性被诸多勘探作业选为载体。虚假数据注入(false data injection, FDI)攻击是一种基于数据层的攻击方式,它通过将攻击数据注入到目标系统原始输出数据中,从... 详细信息

水下机器人在海洋勘探中起着至关重要的作用,其以高机动性和线性控制系统的简易性被诸多勘探作业选为载体。虚假数据注入(false data injection, FDI)攻击是一种基于数据层的攻击方式,它通过将攻击数据注入到目标系统原始输出数据中,从而使设备无法正常运行。由于FDI攻击只注入到系统数据中,因此它还具有很强的隐蔽性,这就意味着设备被发现非正常运行时系统即已被入侵。提出了一种基于水下机器人的多项式回归非模型预测控制方法,该方法可以削弱FDI攻击的攻击强度。FDI攻击者的目标是通过篡改系统数据来破坏控制系统乃至设备的完整,而不是为了窃取关键信息,因此,为了应对攻击,仅需考虑加强系统的检测能力或削弱攻击强度即可。通过多项式回归的方法对所有数据集进行关联式处理,将数据集中的原始数据与攻击数据相结合,从而保证系统即使受到FDI攻击也能稳定运行。最后,通过仿真验证了所提出方法的有效性。

关键词：线性预测控制系统非模型预测控制虚假数据注入攻击控制系统安全多项式回归

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基于动态事件的水面无人船故障检测

控制工程 2023年第12期30卷 2192-2198页

作者：白盼鑫张恒王哲李宏然张键江苏海洋大学计算机工程学院江苏连云港222000 江苏海洋大学电子工程学院江苏连云港222000 江苏海洋大学海洋技术与测绘学院江苏连云港222000

在基于网络控制的水面无人船(unmanned surface vehicles,USV)系统中,针对系统执行器故障和使用通信网络出现的网络延迟、数据丢失,以及海洋环境扰动,研究基于动态事件触发的水面无人船系统的故障检测问题。首先,量化影响因素,构建了一... 详细信息

在基于网络控制的水面无人船(unmanned surface vehicles,USV)系统中,针对系统执行器故障和使用通信网络出现的网络延迟、数据丢失,以及海洋环境扰动,研究基于动态事件触发的水面无人船系统的故障检测问题。首先,量化影响因素,构建了一个考虑网络延迟、丢失、海洋扰动和执行器故障同时存在的水面无人船系统的动力学模型。并在此基础上构建了一个基于动态事件触发的无人船系统故障检测框架,给出了动态事件触发的条件。然后,利用李雅普诺夫稳定性理论给出了残差系统渐近稳定的判据和系统故障检测框架的参数设计方法。最后,通过仿真实验验证了所提出的故障检测方法的有效性。

关键词：故障检测水面无人船事件触发机制系统故障

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坚守信仰守望文学——重读陆地

南方文坛 2010年第2期 98-100页

作者：李鸿然海南大学人文传播学院中国少数民族文学学会

陆地是中国当代文学大家。他20世纪30年代末步入文坛，至今走过了长达七十年的创作历程。其人生经历和创作生涯，是一部可读性很强的传奇。考察其文学创作的贡献，不妨使用三个相互关联的文学坐标：在民族文学坐标上，陆地是当代壮族文... 详细信息

陆地是中国当代文学大家。他20世纪30年代末步入文坛，至今走过了长达七十年的创作历程。其人生经历和创作生涯，是一部可读性很强的传奇。考察其文学创作的贡献，不妨使用三个相互关联的文学坐标：在民族文学坐标上，陆地是当代壮族文学之父。他在《新文学史料》1989年第4期上发表的长篇文章《七十回首话当年》，开篇便说：“我是用汉语写作的壮族人。”骨血里的族属意识流淌在笔端，作品必然与千万壮族同胞同心相应，壮族同胞因有陆地而自豪，壮族作家把陆地视为文学旗帜，决不是偶然的；在区域文学坐标上，

关键词：中国当代文学陆地《新文学史料》壮族文学信仰重读守望 30年代

Semi-automated detection of rangeland runoff and erosion control berms using high-resolution topography data

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International Soil and Water Conservation Research 2024年第1期12卷 217-226页

作者： li li Changjiang River Scientific Research Institute of Changjiang Water Resources Commission Wuhan430010China Research Center on Mountain Torrent&Geologic Disaster Prevention Ministry of Water ResourcesWuhan430010China University of Arizona School of Natural Resources and the EnvironmentTucsonAZ85719USA

An inventory of topographic modifications is essential to addressing their impacts on hydrological and morphological processes in human-altered ***,such inventories are generally *** study presents two workflows for semi-automatic detection of linear earthen runoff and erosion control berms in rangelands using high-resolution topographic *** workflows consist of initial object identification by applying either morphological grayscale reconstruction(MGR)or the Geomorphon(GEO)method,followed by identification refinements through filters based on objects’horizontal and vertical *** sites were selected within the Altar Valley,Arizona,in the southwestern United *** site was used for developing workflows and optimizing filter thresholds,and the other two sites were used to validate *** results showed that:1)The MGR-based workflow methodology could produce final precision and detection rates of up to 92%and 75%,respectively,and take less than 5 s for a 10.1 km^(2) site;2)The workflow based on the MGR method yielded greater identification accuracy than did the GEO workflow;3)Object length,orientation,and eccentricity were important characteristics for identifying earthen berms,and are sensitive to general channel flow direction and berm shape;4)Manual interrogation of topographic data and imagery can significantly improve identification precision *** proposed workflows will be useful for developing inventories of runoff and erosion control structures in support of sustainable rangeland management.

关键词： Earthen berm Rangeland Grayscale morphological reconstruction Geomorphon liDAR

Theoretical Analysis of Cooperative Driving at Idealized Unsignalized Intersections

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Tsinghua Science and Technology 2024年第1期29卷 257-270页

作者： Shen li Jiawei Zhang Zhenwu Chen li li Department of Civil Engineering Tsinghua UniversityBeijing 100084China Department of Automation Tsinghua UniversityBeijing 100084China Shenzhen Urban Transport Planning Center Co. Ltd.Shenzhen 518000China

Cooperative driving is widely viewed as a promising method to better utilize limited road resources and alleviate traffic *** recent years,several cooperative driving approaches for idealized traffic scenarios(i.e.,uniform vehicle arrivals,lengths,and speeds)have been ***,theoretical analyses and comparisons of these approaches are *** this study,we propose a unified group-by-group zipper-style movement model to describe different approaches synthetically and evaluate their *** derive the maximum throughput for cooperative driving plans of idealized unsignalized intersections and discuss how to minimize the delay of *** obtained conclusions shed light on future cooperative driving studies.

关键词： cooperative driving connected and automated vehicles unsignalized intersection