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昆虫病原线虫人工培养技术研究与应用进展

昆虫学报 2024年第6期67卷 872-884页

作者：田成丽张金花朱峰韩日畴李茂海吉林省农业科学院(中国农业科技东北创新中心)植物保护研究所农业部东北作物有害生物综合治理重点实验室公主岭136100 广东省科学院动物研究所广东省动物保护与资源利用重点实验室广东省野生动物保护与利用公共实验室广州510260

昆虫病原线虫是昆虫的专化性寄生天敌,可自主搜寻寄主、杀虫速度快、对环境友好安全,是一类重要的害虫生物防治因子,在害虫可持续治理中具有应用潜力。目前,昆虫病原线虫作为商品化的新型生物杀虫制剂在全球生产销售。然而,昆虫病原线... 详细信息

昆虫病原线虫是昆虫的专化性寄生天敌,可自主搜寻寄主、杀虫速度快、对环境友好安全,是一类重要的害虫生物防治因子,在害虫可持续治理中具有应用潜力。目前,昆虫病原线虫作为商品化的新型生物杀虫制剂在全球生产销售。然而,昆虫病原线虫的商品化需要高效的人工培养技术。由于昆虫病原线虫的专化性较强,一种成熟的商业化昆虫病原线虫人工培养技术需要根据线虫种类优化。除了优化现有技术,还需研发新的人工培养技术。本文综述了国内外昆虫病原线虫人工培养技术研究和应用的历史和现状,详细介绍了活体培养技术和离体培养技术,讨论了影响昆虫病原线虫产量的主要因素,强调了优化人工培养技术并降低培养成本的必要性。未来,随着人工培养技术的不断优化,在丰富了昆虫病原线虫商品化种类的同时,还可降低农业生产的经济损失,改良土壤环境,具有重要的经济和社会价值。

关键词：昆虫病原线虫活体培养固体培养液体培养固液双相培养应用技术

Approximate Gaussian conjugacy： parametric recursive filtering under nonlinearity, multimodality, uncertainty, and constraint, and beyond

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Frontiers of Information Technology & Electronic Engineering 2017年第12期18卷 1913-1939页

作者： tian-cheng LIn Jin-ya SU Wci LIU Juan M. CORCHADO School of Sciences University of Salamanca Salamanca 37007 Spain Department of Aeronautical and Automotive Engineering Loughborough University Loughborough LE11 3TU UK De~artment of Electronic and Electrical En.oineering University of She3ff~eld She3ff~eld $1 ~ET UK

Since the landmark work of R. E. Kalman in the 1960s, considerable efforts have been devoted to time series state space models for a large variety of dynamic estimation problems. In particular, parametric filters that seek analytical estimates based on a closed-form Markov-Bayes recursion, e.g., recursion from a Gaussian or Gaussian mixture （GM） prior to a Gaussian/GM posterior （termed ＇Gaussian conjugacy＇ in this paper）, form the backbone for a general time series filter design. Due to challenges arising from nonlinearity, multimodality （including target maneuver）, intractable uncertainties （such as unknown inputs and/or non-Gaussian noises） and constraints （including circular quantities）, etc., new theories, algorithms, and technologies have been developed continuously to maintain such a conjugacy, or to approximate it as close as possible. They had contributed in large part to the prospective developments of time series parametric filters in the last six decades. In this paper, we review the state of the art in distinctive categories and highlight some insights that may otherwise be easily overlooked. In particular, specific attention is paid to nonlinear systems with an informative observation, multimodal systems including Gaussian mixture posterior and maneuvers, and intractable unknown inputs and constraints, to fill some gaps in existing reviews and surveys. In addition, we provide some new thoughts on alternatives to the first-order Markov transition model and on filter evaluation with regard to computing complexity.

关键词： Kalman filter Gaussian filter Time series estimation Bayesian filtering Nonlinear filtering Constrained filtering Gaussian mixture Maneuver Unknown inputs

385 m高大跨越输电塔塔身和横担的体型系数和角度风系数

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空间结构 2024年第1期30卷 55-61页

作者：朱姣李布辉季天程沈国辉沈文韬国网江苏省电力有限公司建设分公司江苏南京210024 中国能源建设集团江苏省电力设计院有限公司江苏南京211102 浙江大学建筑工程学院浙江杭州310058

针对某385 m高大跨越输电塔塔身和横担进行测力风洞试验,获得塔身和横担的气动力系数,给出塔身、上横担和下横担的体型系数和角度风分配系数,并与各国规范的规定值进行对比.研究表明,有井筒塔身的阻力系数小于不带井筒塔身的阻力系数,... 详细信息

针对某385 m高大跨越输电塔塔身和横担进行测力风洞试验,获得塔身和横担的气动力系数,给出塔身、上横担和下横担的体型系数和角度风分配系数,并与各国规范的规定值进行对比.研究表明,有井筒塔身的阻力系数小于不带井筒塔身的阻力系数,其原因为井筒受到塔身的显著遮挡;无井筒塔身的体型系数和GB、DL/T、AS/NZS规范接近,小于ASCE规范值;塔身顺线路方向的角度风分配系数在10°~15°风向出现最大值,各国规范中均没有体现;横担的体型系数比GB、DL/T和AS/NZS规范略大;横担顺线路方向的角度风分配系数和BSEN规范结果非常接近.

关键词：大跨越输电塔风洞试验体型系数角度风分配系数测力天平

机插种植均匀度对水稻产量构建及品质形成的影响

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作物学报 2024年第10期50卷 2625-2636页

作者：唐承翰陈惠哲叶天承张玉屏向镜张义凯王志刚王亚梁中国水稻研究所/水稻生物育种全国重点实验室浙江杭州311400

水稻种植均匀度对产量和品质有显著的影响,本试验旨在明确均匀度的提高协同产量和品质提升的机理。试验选用籼粳杂交稻甬优1540,常规粳稻浙禾香2号,杂交籼稻华浙优210为供试品种,设置4种不同种植均匀度处理:T_(1)(条播机插,种植均匀度65... 详细信息

水稻种植均匀度对产量和品质有显著的影响,本试验旨在明确均匀度的提高协同产量和品质提升的机理。试验选用籼粳杂交稻甬优1540,常规粳稻浙禾香2号,杂交籼稻华浙优210为供试品种,设置4种不同种植均匀度处理:T_(1)(条播机插,种植均匀度65%~75%)、T_(2)(撒播机插,种植均匀度45%~55%)、T_(3)(人工模拟机插,种植均匀度100%)、T_(4)(人工模拟机插,种植均匀度50%),比较不同种植均匀度群体的分蘖动态变化、叶面积光合效能、干物质积累与转运、产量形成及稻米品质的变化。结果表明:(1)种植均匀度提高通过促进分蘖增加了群体有效分蘖数,3个品种平均分蘖高峰苗数表现为T_(3)>T_(1)>T_(2)>T_(4),不同品种在处理间变化趋势一致。(2)种植均匀度的提高增加了群体叶面积指数,同时显著提高了抽穗期上三叶高效叶面积指数。而且,增加均匀度显著提高了干物质积累并促进了植株干物质转运,成熟期干物质积累量表现为T_(3)>T_(1)>T_(2)>T_(4),品种间趋势一致,但是T_(2)跟T_(4)差异不明显。均匀度提高对灌浆期茎鞘物质运转有一定促进作用,品种间存在差异,T_(1)、T_(2)和T_(4)间差异不明显。(3)不同均匀度处理下每穗粒数无显著性差异,但高均匀度下一次枝梗和二次枝梗的着粒分布更均匀。(4)高均匀度群体主要通过有效穗数提高产量,品种间趋势一致,T_(3)比T_(1)、T_(2)、T_(4)平均产量分别高8.16%、15.41%、15.61%。(5)提高种植均匀度提高了稻米糙米率、精米率、整精米率和蛋白质含量,降低了稻米垩白米率和垩白度。以上结果表明,提高种植均匀度能够促进群体分蘖,增加群体叶面积指数和干物质积累,提高有效穗数,从而提升了稻谷产量和出米率,并一定程度上改善了稻米品质。试验结果明确生产上采用精准条播育秧机插能够通过提高种植均匀度协同提升稻谷产量和稻米品质。

关键词：水稻种植均匀度播种方式产量稻米品质

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Evaluating and Constraining Hardware Assertions with Absent Scenarios

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Journal of Computer Science & Technology 2020年第5期35卷 1198-1216页

作者： Hui-Na Chao Hua-Wei Li Xiaoyu Song tian-cheng Wang Xiao-Wei Li State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China Peng cheng Laboratory Shenzhen 518052China Department of Electrical and Computing Engineering Portland State UniversityPortlandOR 97207U.S.A.

Mining from simulation data of the golden model in hardware design verification is an effective solution to assertion *** the simulation data is inherently incomplete,it is necessary to evaluate the truth values of the mined *** paper presents an approach to evaluating and constraining hardware assertions with absent scenarios.A Belief-fail Rate metric is proposed to predict the truth/falseness of generated *** considering both the occurrences of free variable assignments and the conflicts of absent scenarios,we use the metric to sort true assertions in higher ranking and false assertions in lower *** Belief-failRate guided assertion constraining method leverages the quality of generated *** experimental results show that the Belief-failRate framework performs better than the existing *** addition,the assertion evaluating and constraining procedure can find more assertions that cover new design functionality in comparison with the previous methods.

关键词： hardware formal verification assertion generation data mining assertion evaluation assertion coverage

高频超声与低频超声联合检查诊断小儿肠套叠的价值

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中国医疗器械信息 2024年第8期30卷 125-127页

作者：刘洁郑天成韦朝清厦门长庚医院超声科福建厦门361000

目的:分析高频超声与低频超声联合检查诊断小儿肠套叠的价值。方法:选取2021年1月~2023年4月本院收治的83例疑似小儿肠套叠患儿,所有患儿均接受高频超声、低频超声检查,参考X线空气灌肠检查结果,分析不同检查方式准确率。结果:83例疑似... 详细信息

目的:分析高频超声与低频超声联合检查诊断小儿肠套叠的价值。方法:选取2021年1月~2023年4月本院收治的83例疑似小儿肠套叠患儿,所有患儿均接受高频超声、低频超声检查,参考X线空气灌肠检查结果,分析不同检查方式准确率。结果:83例疑似小儿肠套叠患儿经低频超声检查53例为真阳性,19例为真阴性,经高频、低频超声联合检查,60例为真阳性,22例为真阴性;低频超声单独检查和高频超声与低频超声联合检查误诊率、特异度对比无明显差异(P>0.05),高频超声与低频超声联合检查准确度、灵敏度明显比低频超声单独检查高(P<0.05),漏诊率比低频超声单独检查低(P<0.05)。结论:小儿肠套叠应用高频超声与低频超声联合检查,可以更准确地对患儿病情进行诊断,避免漏诊、误诊。

关键词：高频超声低频超声小儿肠套叠准确率诊断效能

Binary self-assembly of highly symmetric DNA nanocages via sticky-end engineering

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Chinese Chemical Letters 2017年第4期28卷 851-856页

作者： Xiao-Rong Wu Chen-Wei Wu Fei Ding cheng tian Wen Jiang cheng-De Mao Chuan Zhang School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix Composites Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing Shanghai Jiao Tong University Shanghai 200240 China Departments of Chemistry Purdue University West Lafayette IN 47906 USA

Discrete and symmetric three-dimensional（3D） DNA nanocages have been revoked as excellent candidates for various applications,such as guest component encapsulation and organization（*** molecules,proteins,inorganic nanoparticles,etc.） to construct new materials and *** date,a large variety of DNA nanocages has been synthesized through assembling small individual DNA motifs into predesigned structures in a bottom-up *** of them rely on the assembly using multiple copies of single type of motifs and a few sophisticated nanostructures have been engineered by co-assembling multi-types of DNA tiles ***,the availability of complex DNA nanocages is still ***,we demonstrate that highly symmetric DNA nanocages consisted of binary DNA pointstar motifs can be easily assembled by deliberately engineering the sticky-end interaction between the component building *** such,DNA nanocages with new geometries,including elongated tetrahedron（E-TET）,rhombic dodecahedron（R-DOD）,and rhombic triacontahedron（R-TRI） are successfully ***,their design principle,assembly process,and structural features are revealed by polyacryalmide gel electrophoresis（PAGE）,atomic force microscope（AFM） imaging,and cryogenic transmission electron microscope imaging（cryo-TEM） associated with single particle reconstruction.

关键词： DNA nanotechnology Self-assembly Nanocage Point-star motif Sticky-end

Resampling methods for particle filtering: identical distribution, a new method, and comparable study

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Frontiers of Information Technology & Electronic Engineering 2015年第11期16卷 969-984页

作者： tian-cheng LI Gabriel VILLARRUBIA Shu-dong SUN Juan M.CORCHADO Javier BAJO BISITE Group Faculty of Science University of Salamanca School of Mechanical Engineering Northwestern Polytechnical University Osaka Institute of Technology Department of Artificial Intelligence Technical University of Madrid

Resampling is a critical procedure that is of both theoretical and practical significance for efficient implementation of the particle filter. To gain an insight of the resampling process and the filter, this paper contributes in three further respects as a sequel to the tutorial （Li et al., 2015）. First, identical distribution （ID） is established as a general principle for the resampling design, which requires the distribution of particles before and after resampling to be statistically identical. Three consistent met- rics including the （symmetrical） Kullback-Leibler divergence, Kolmogorov-Smimov statistic, and the sampling variance are introduced for assessment of the ID attribute of resampling, and a corresponding, qualitative ID analysis of representative resampling methods is given. Second, a novel resampling scheme that obtains the optimal ID attribute in the sense of minimum sampling variance is proposed. Third, more than a dozen typical resampling methods are compared via simulations in terms of sample size variation, sampling variance, computing speed, and estimation accuracy. These form a more comprehensive under- standing of the algorithm, providing solid guidelines for either selection of existing resampling methods or new implementations

关键词： Particle filter Resampling Kullback-Leibler divergence Kolmogorov-Smimov statistic

THREE-DIMENSIONAL NUMERICAL SIMULATION OF THERMAL-HYDRAULIC PERFORMANCE OF A CIRCULAR TUBE WITH EDGEFOLD-TWISTED-TAPE INSERTS

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Journal of Hydrodynamics 2010年第5期22卷 662-670页

作者： CUI Yong-zhang tian Mao-cheng School of Energy and Power Engineering Shandong University Jinan 250061 China School of Thermal Engineering Shandong Jianzhu University Jinan 250101 China

Three-dimensional numerical simulations and experiments were carried out to study the heat transfer characteristics and the pressure drop of air flow in a circular tube with Edgefold-Twisted Tape （ETT） inserts and with classic Spiral-Twisted-Tape （STT） inserts of the same twist ratio. The RNG turbulence model for mildly swirling flows, the enhanced wall treatment for low Reynolds numbers, and the SIMPLE pressure-velocity method were adopted to simulate the flow and heat transfer characteristics. Within the range of Reynolds number from 2 500 to 9 500 and the twist ratio y from 5.4 to 11.4, the Nusselt number of the tube with ETT inserts is found to be 3.9% - 9.2% higher than that with STT inserts, and the friction factor of the tube with ETT inserts is 8.7% - 74% higher than that of STT inserts. The heat enhancement is due to higher tangential velocity and asymmetrical velocity profile with the increase and decrease of the periodic velocity within an edgefold length. It is found that main factors affecting the heat transfer of ETT inserts are the twist angle and the gap width between the tube and inserts. A larger twist angle leads to a higher tangential velocity, and larger Nusselt number and friction factor. The thermal-hydraulic performance slowly decreases as the twist angle increases. The gap width between tube and inserts has a significant influence on the heat transfer, while little influence on pressure drops. The thermal-hydraulic performance increases in average by 124% and 140% when the gap width reduces from 1.5 mm to 1.0 mm and 0.5 mm. The larger the gap width, the higher velocity through the gap will be, which would reduce the main flow velocity and tangential velocity. So a small gap is desirable. Comparing experimental and numerical results at variable air flow and tube wall temperature, the numerical results are found to be in a reasonable agreement with the experiment results, with difference of the Nusselt number in a range of 1.6% - 3.6%, and tha

关键词： heat transfer enhancement Edgefold-Twisted-Tape (ETT) Spiral-Twisted-Tape (STT) thermal-hydraulic performance