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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG Bing-zhen wang shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily dependent.Under some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite interval.If we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

On the strong convergence properties for weighted sums of negatively orthant dependent random variables

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Applied Mathematics(A Journal of Chinese Universities) 2018年第1期33卷 35-47页

作者： DENG Xin TANG Xu-fei wang shi-jie wang Xue-jun School of Mathematical Sciences Anhui University

In the paper, the strong convergence properties for two different weighted sums of negatively orthant dependent(NOD) random variables are investigated. Let {X, n ≥ 1}be a sequence of NOD random variables. The results obtained in the paper generalize the corresponding ones for i.i.d. random variables and identically distributed NA random variables to the case of NOD random variables, which are stochastically dominated by a random variable X. As a byproduct, the Marcinkiewicz-Zygmund type strong law of large numbers for NOD random variables is also obtained.

关键词： strong convergence negatively orthant dependent random variables stochastic domination

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非道路柴油机缸筒芯的快速改型工艺

铸造 2024年第5期73卷 706-709页

作者：许海铎薛文璞王世杰第一拖拉机股份有限公司制造工程中心河南洛阳471000 中国一拖集团有限公司河南洛阳471000

在柴油机缸体新产品的开发过程中,往往使用模具造型(芯)、无模数字化精密成形技术切削成形、喷墨3D打印成形等方法先制造砂型,再将金属液浇注入砂型中形成铸件,但是上述制备砂型的方法有的造型周期长、有的砂型制造成本高。因此,本文研... 详细信息

在柴油机缸体新产品的开发过程中,往往使用模具造型(芯)、无模数字化精密成形技术切削成形、喷墨3D打印成形等方法先制造砂型,再将金属液浇注入砂型中形成铸件,但是上述制备砂型的方法有的造型周期长、有的砂型制造成本高。因此,本文研究了一种快速改型方法,将原有砂型改造成为可以再次用于缸体新产品生产的新砂型,使缸体新产品开发过程中砂型制造成本降低39.2%,具有较好的推广应用价值。

关键词：缸体快速改型结构特征

Features of soil redistribution and major element migration in a karst hillslope of Southwest China

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Journal of Mountain Science 2018年第9期15卷 1892-1908页

作者： SONG Chang-shun JI Hong-bing Howard Omar BECKFORD CHU Hua-shuo ZHANG Kun wang shi-jie State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Graduate University of the Chinese Academy of Sciences Beijing 100049China

In this study, we investigated the spatial characteristics of the rate of soil distribution and the mechanism of major element migration in a typical karst hillslope in Guangxi Province, Southwestern China. Soil redistribution was examined using (137~)Cs technique under different hillslope components. With the combination of geochemical methods, the migration characteristics of major elements in soils of three hillslope components in both the horizontal and vertical directions were determined. Thirty-seven soil samples were collected and analyzed for 137 Cs and the major elements were determined. By using the profile distribution model the mean soil redistribution rates were found to be-17.01, 0.40 and-23.30t ha-1 yr-1 in the summit(BYSD), shoulder(BYSY) and toeslope(BYSJ) components of the studied hillslope, respectively. In comparison to BYSD, the sesquioxides of Fe_2O_3 and TiO_2 tend to be enriched, whereas the alkalis(CaO, MgO, Na_2O and K_2O) tend to be depleted, both in the shoulder and toeslope components. Due to human and animal activities, the contents of CaO, MgO, K_2O and Na_2O have somewhat increased within the topsoil. The results indicated that (137~)Cs activities are significantly correlated with clay particles and organic matter, and are affected by the pedogenic process and vegatation. Overall, it maybe necessary to use techniques such as (137~)Cs to investigate soil erosion with the combination of geochemical methods.

关键词：土壤样品石灰岩地区空间特征再分配元素地形中国西南

杨树UGT198基因的生物信息学分析、基因克隆及功能初探

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西南农业学报 2024年第1期37卷 14-22页

作者：杨改霞王春雨龙连香王世杰顾丽姣河北农业大学林学院/河北省林木种质资源与森林保护重点实验室河北保定071001

【目的】研究UGT198基因是否参与调控烟草抗虫性,为未来探索其参与调控杨树抗虫性奠定基础。【方法】前期通过分析公共转录组数据发现PtrUGT198基因在杨树响应虫害的转录组中高调表达,对其进行生物信息学及进化分析。以107杨为材料,克隆... 详细信息

【目的】研究UGT198基因是否参与调控烟草抗虫性,为未来探索其参与调控杨树抗虫性奠定基础。【方法】前期通过分析公共转录组数据发现PtrUGT198基因在杨树响应虫害的转录组中高调表达,对其进行生物信息学及进化分析。以107杨为材料,克隆UGT198基因,构建过量表达载体,利用农杆菌介导法转化烟草获得过量表达转基因株系。通过棉铃虫饲虫试验初步验证UGT198基因是否参与调控抗虫性,分析UGT198基因在调控抗虫性中发挥的功能。【结果】PtrUGT198基因完整的ORF区为1440 bp,编码479个氨基酸,理论分子量为53.14 kDa,等电点为5.92,编码不稳定疏水性蛋白。PtrUGT198蛋白的二级结构α⁃螺旋占41.75%,β⁃折叠占14.61%,β⁃转角占7.10%,无规卷曲占6.53%。PtrUGT198蛋白不存在跨膜区,预测其不属于膜蛋白,为非分泌性蛋白,该蛋白的磷酸化修饰以丝氨酸为主。同源序列对比结果显示PtrUGT198蛋白的C末端存在高度保守的植物次生产物糖基转移酶(Plant secondary product glycosyltransferase,PSPG)基序。系统进化树分析发现,PtrUGT198蛋白与同属植物毛白杨、银白杨和胡杨亲缘关系最近,其次和模式植物烟草有较近的亲缘关系。成功克隆杨树UGT198基因,构建pNC⁃UGT198基因过量表达载体,并转化烟草获得过量表达转基因株系,进行饲虫实验,得到高表达量烟草相对抗虫。【结论】首次成功克隆了UGT198基因,并初步解析其调控抗虫性的功能,为深入了解UGT198基因调控杨树抗虫机理提供参考价值。

关键词：杨树 UGT198 生物信息学基因克隆过表达转基因株系

棕鞭金藻异养-光照耦合高密度培养生产岩藻黄素条件优化

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水生生物学报 2024年第6期48卷 1029-1039页

作者：郭羽芬王诗洁陈宝峰王思门君乔志仙罗洪镇金虎淮阴工学院生命科学与食品工程学院淮安223003 中国科学院水生生物研究所水生生物分子与细胞生物学研究中心武汉430072 中国科学院水生生物研究所分析测试中心武汉430072

为探究棕鞭金藻生产岩藻黄素的综合性能,以期建立高效合成岩藻黄素的发酵工艺,研究首先对金藻发酵培养基中的碳氮比、维生素添加量进行优化。结果表明,当碳氮比为24、维生素添加量为3.75 mg/L维生素B_(1)和1.25 mg/L维生素B_(12)时,有... 详细信息

为探究棕鞭金藻生产岩藻黄素的综合性能,以期建立高效合成岩藻黄素的发酵工艺,研究首先对金藻发酵培养基中的碳氮比、维生素添加量进行优化。结果表明,当碳氮比为24、维生素添加量为3.75 mg/L维生素B_(1)和1.25 mg/L维生素B_(12)时,有利于金藻细胞内的岩藻黄素高效合成。此外,通过调控金藻光/暗培养模式,对其在不同条件下的细胞生长、最大光合效率和岩藻黄素积累情况进行比较研究,结果显示从种子培养到上罐发酵全过程进行光诱导后,胞内岩藻黄素含量显著提升。通过系统优化,金藻发酵后的胞内岩藻黄素含量和产量分别达到1.79 mg/g和33.6 mg/L,比优化前的发酵水平提高33.6%和31.2%。研究利用发酵优化技术强化了棕鞭金藻的岩藻黄素积累,为后续进一步进行大规模过程放大奠定了前期基础,也为其他微藻生产岩藻黄素提供了借鉴和参考。

关键词：岩藻黄素马勒姆杯棕鞭金藻异养-光照耦合培养微藻发酵

Analysis on the Chemical Characteristics of Shallow Groundwater and Causes of Formation in the Area around Poyang Lake

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Meteorological and Environmental Research 2011年第9期2卷 77-80页

作者： YANG Tao wang shi-jie State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China Graduate University of Chinese Academy of Sciences Beijing 100049China

[Objective] The study aimed at analysing the chemical characteristics of shallow groundwater and causes of formation around Poyang Lake area. [Method] The quality of shallow groundwater under seven counties or cities around Poyang Lake was investigated in 2010, and compared different regions from salinity, hardness, conductivity, hydrochemistry types and so forth, so as to reveal the status quo, change characteristics and reasons of shallow groundwater. [Result] Except for pH, other water quality indicators of shallow groundwater around Poyang Lake were better, attaining Class I water quality standards. Among these regions, the salinity, hardness, conductivity, Na+, K+, Ca2+, Mg2+, Cl- and HCO-3 concentration of shallow groundwater in Nanchang city were up to the maximum values, while pH and SO2-4 concentration were the highest in Duchang County; Mg2+ concentration and pH were the lowest in Poyang County, and hardness, K+, Ca2+, SO2-4 and Cl- concentration in Yongxiu County reached the minimum values, while Na+ concentration, salinity and conductivity were the lowest in Jinxian County. In addition, the better quality of groundwater around Poyang Lake was closely related to the low level of economic development in Jiangxi Province. Meanwhile, many water quality indices in Nanchang City reached the maximum values, and even tended to Class Ⅱ water quality standards, which resulted from the high level of economic development and decisive role of human activities. [Conclusion] The research could provide references for the establishment of management strategies for regional shallow groundwater.

关键词： Poyang Lake Shallow groundwater Chemical characteristics China

PROGRESS OF SMCE CHEMISTRY RESEARCH IN CHINA DURING 1995─1997

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空间科学学报 1998年第S1期18卷 21-26页

作者： wang shi-jie OUYANG Zi-yuan (State Key Laboratorp of Environmental Geochemistry,Institute of Geochemistry, The Chinese Academy of Sciences, Guiyang 550002)

Over the past years Chinese space chemists have done much work on space chemistry and related disciplines, especially on the solar nebular evolution,meteorjtes, comparative planetology and the origin and evolution of the Earth.In this paper, the authors outline the main achievements and briefly describe some new views and hypotheses.

关键词： Progress Space chemistry

唾液酸化IgG在肺腺癌中高表达并促进肺腺癌增殖和迁移

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中日友好医院学报 2024年第3期38卷 148-153,F0003页

作者：葛舒童王诗杰朱广迎北京大学中日友好临床医学院放射肿瘤科北京100029 中国医学科学院北京协和医学院北京100730 中日友好医院国家呼吸医学中心放射肿瘤科北京100029

目的:探究唾液酸化IgG(SIA-IgG)在肺腺癌(LUAD)中的表达和功能,以及抗SIA-IgG抗体(RP215抗体)对小鼠体内Lewis肺腺癌生长和肿瘤微环境的影响。方法:应用癌症基因组图谱(TCGA)数据库对IgG重链γ恒定区(IGHG)基因进行泛癌分析;用Kaplan-Me... 详细信息

目的:探究唾液酸化IgG(SIA-IgG)在肺腺癌(LUAD)中的表达和功能,以及抗SIA-IgG抗体(RP215抗体)对小鼠体内Lewis肺腺癌生长和肿瘤微环境的影响。方法:应用癌症基因组图谱(TCGA)数据库对IgG重链γ恒定区(IGHG)基因进行泛癌分析;用Kaplan-MeierPlotter数据库分析IGHG基因表达与肺腺癌患者预后的关系。克隆形成实验和迁移实验分别评估沉默SIA-IgG后肺腺癌细胞的增殖和迁移能力的变化。采用LLC细胞在雌性C57BL/6小鼠(6周龄)体内成瘤并给予RP215抗体治疗,观察小鼠体内肿瘤的生长状况,流式分析观察RP215治疗对肿瘤微环境的影响。结果:泛癌分析,IgG在肺腺癌中表达上调(P<0.01)且与患者的不良预后呈正相关。小鼠实验,沉默SIA-IgG的表达后,肺腺癌细胞的增殖和迁移能力受到明显抑制(均P<0.01)。RP215抗体治疗可明显抑制小鼠体内Lewis肺腺癌的生长(P<0.05),且小鼠肿瘤微环境中的巨噬细胞和中性粒细胞比例降低(P<0.05)。结论:SIA-IgG或可作为肺腺癌的潜在治疗靶点。

关键词：肺腺癌唾液酸化免疫球蛋白G 增殖迁移

Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification

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Defence Technology（防务技术） 2024年第1期31卷 375-386页

作者： jie Zhao Zhongjiao shi Yuchen wang Wei wang Beijing Institute of Technology Beijing 100081China

This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system uncertainties.First,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference frames.Next,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F dynamics.Then,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression matrix.As long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be achieved.Finally,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations.

关键词： Rotor-missile Adaptive control Parameter identification Quaternion control