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Establishing cell suitability for high-level production of licorice triterpenoids in yeast

Acta Pharmaceutica Sinica B 2024年第9期14卷 4134-4148页

作者： Wentao Sun Shengtong Wan Chuyan Liu Ruwen Wang Haocheng Zhang Lei Qin Runming Wang bo lv Chun Li Department of Chemical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering Ministry of Industry and Information TechnologyInstitute of Biochemical EngineeringSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China The University of Chicago ChicagoIL 60637USA Key Lab for Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Yeast has been an indispensable host for synthesizing complex plant-derived naturalcompounds, yet the yields remained largely constrained. This limitation mainly arises from overlookingthe importance of cell and pathway suitability during the optimization of enzymes and pathways. Herein,beyond conventional enzyme engineering, we dissected metabolic suitability with a framework forsimultaneously augmenting cofactors and carbon flux to enhance the biosynthesis of heterogenoustriterpenoids. We further developed phospholipid microenvironment engineering strategies, dramaticallyimproving yeast’s suitability for the high performance of endoplasmic reticulum (ER)-localized, ratelimitingplant P450s. Combining metabolic and microenvironment suitability by manipulating only threegenes, NHMGR (NADH-dependent HMG-CoA reductase), SIP4 (a DNA-binding transcription factor)andGPP1 (Glycerol-1-phosphate phosphohydrolase 1), we enabled the high-level production of 4.92 g/L rarelicorice triterpenoids derived from consecutive oxidation of b-amyrin by two P450 enzymes afterfermentation optimization. This production holds substantial commercial value, highlighting the criticalrole of establishing cell suitability in enhancing triterpenoid biosynthesis and offering a versatileframework applicable to various plant natural product biosynthetic pathways.

关键词： Cell suitability Phospholipid microenvironment Cytochrome P450 Triterpenoids Saccharomyces cerevisiae

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Independent control of circularly polarized light with exceptional topological phase coding metasurfaces

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Photonics Research 2024年第6期12卷 534-542页

作者： YICHENG LI SHICHENG WAN SHAOXUAN DENG ZHENGWEI DENG bo lv CHUNYING GUAN JUN YANG ANDREY boGDANOV PAVEL BELOV JINHUI SHI Key Laboratory of Photonic Materials and Devices Physics for Oceanic Applications Ministry of Industry and Information TechnologyCollege of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China Key Laboratory of In-Fiber Integrated Optics of Ministry of Education College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China School of Physics and Engineering ITMO UniversitySt.Petersburg 197101Russia School of Information Engineering Guangdong University of TechnologyGuangzhou 510008China Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Exceptional points,as degenerate points of non-Hermitian parity-time symmetric systems,have many unique physical *** to its flexible control of electromagnetic waves,a metasurface is frequently used in the field of *** this work,we developed a parity-time symmetric metasurface and implemented the 2πtopological phase surrounding an exceptional *** with Pancharatnam-Berry phase,the topological phase around an exceptional point can achieve independent regulation of several circular polarization *** combined the Pancharatnam-Berry phase with the exceptional topological phase and proposed a composite coding metasurface to achieve reflection decoupling of different circular *** work provides a design idea for polarimetric coding metasurfaces in the future.

关键词： properties. exceptional topological

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基于Philips棱镜3CMOS相机的光学设计及其光谱优化

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中国光学（中英文） 2024年第3期17卷 648-660页

作者：陈塑淏吕博刘伟奇中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

针对彩色数字相机高成像质量以及高色准的需求,本文研究了基于Philips棱镜的3CMOS相机的光学系统设计以及相机光谱优化方法。通过对Philips棱镜进行光路建模,优化了棱镜的结构参数。在保证全内反射以及出射窗口大小的条件下,减小了系统... 详细信息

针对彩色数字相机高成像质量以及高色准的需求,本文研究了基于Philips棱镜的3CMOS相机的光学系统设计以及相机光谱优化方法。通过对Philips棱镜进行光路建模,优化了棱镜的结构参数。在保证全内反射以及出射窗口大小的条件下,减小了系统的体积,并由此设计了Philips棱镜3CMOS相机光学系统。其视场角为45°,相对孔径为1/2.8,在110 lp/mm的奈奎斯特采样频率下,系统的MTF全视场全波段均大于0.4。基于色度学基本原理建立了Philips棱镜相机的矢量成像模型,分析了由光线入射角度变化造成的薄膜光谱偏移,提出了宽光束下光谱偏移的修正模型。利用该模型设计并优化了相机中的4组光学薄膜。通过光路仿真实验以及色差分析,基于优化后的相机光学系统的平均色差降低了15.8%,像面颜色不均匀性降低了60%。结果表明:本文设计的光学系统拥有良好的成像质量,优化后的相机光谱实现了良好的颜色性能以及颜色均匀性。

关键词：光学设计 3CMOS相机色度学相机光谱优化

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炭素煅烧烟道内衬选型分析

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轻金属 2024年第8期 35-37页

作者：吕博沈阳铝镁设计研究院有限公司辽宁沈阳110001

随着近年来煅烧烟道内衬多种新型耐火和保温材料的成功研发应用,煅烧烟气余热利用向着更加高效节能、轻型化、施工简便、长寿命、低成本的方向发展。本文对比分析炭素行业各种煅烧烟道内衬材料种类、结构和参数。根据不同的施工条件和... 详细信息

随着近年来煅烧烟道内衬多种新型耐火和保温材料的成功研发应用,煅烧烟气余热利用向着更加高效节能、轻型化、施工简便、长寿命、低成本的方向发展。本文对比分析炭素行业各种煅烧烟道内衬材料种类、结构和参数。根据不同的施工条件和生产需求,列出了烟道内衬材料选择的依据和结论,为工程设计和施工企业的技术人员提供了重要的参考和设计依据。

关键词：炭素煅烧烟道内衬结构及材料参数对比选择依据

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天然产物生物合成与微生物制造的挑战

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中国生物工程杂志 2024年第1期44卷 72-87页

作者：李秋阳孙文涛秦磊吕波李春北京理工大学医药分子科学与制剂工程工信部重点实验室化学与化工学院生物化工研究所北京100081 清华大学化学工程系北京100084 中国医学科学院药物研究所天然药物活性物质与功能国家重点实验室北京100050 清华大学工业生物催化教育部重点实验室北京100084

天然产物是大自然赐予人类的资源宝库,与人类的生活质量和健康息息相关。利用传统方式获取天然产物存在含量低、提取工艺复杂耗时以及资源不可持续等问题,而化学合成步骤繁琐、成本高,这些都严重制约了天然产物的广泛应用。合成生物学... 详细信息

天然产物是大自然赐予人类的资源宝库,与人类的生活质量和健康息息相关。利用传统方式获取天然产物存在含量低、提取工艺复杂耗时以及资源不可持续等问题,而化学合成步骤繁琐、成本高,这些都严重制约了天然产物的广泛应用。合成生物学赋能的微生物细胞工厂通过变革天然产物的传统获取方式,实现高效、绿色及可持续的生物制造。分析天然产物传统获取方式面临的挑战,总结不同类型微生物细胞工厂的特点及天然产物合成案例。基于天然产物代谢通路的复杂性、底盘细胞的稳定性可能导致产物的结构和性质难以预测以及纯度和收率低等问题,从催化元件的局限、途径组装调控及底盘网络重塑的角度分析设计微生物细胞工厂的应对策略,并针对微生物制造产品的发展与应用提出政策建议。

关键词：天然产物生物制造微生物细胞工厂底盘细胞生物安全

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Motion characteristics and density separation of fine coal in an inflatable-inclined liquid-solid fluidized bed

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Particuology 2021年第5期19卷 299-307页

作者： bo lv bobing Dong Xiaowei Deng Chaojun Fang College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Henan Key Laboratory for Green and Efficient Mining&Comprehensive Utilization of Mineral Resources Henan Polytechnic UniversityJiaozuo 454000China Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization Henan Polytechnic UniversityJiaozuo 454000China

To improve the adaptability of fluidized beds for fine coal separation,a new type of liquid-solid fluidized bed was constructed,i.e.,the inflatable-inclined liquid-solid fluidized bed(IILSFB).A combination of simulation analysis and separation experiments was used to analyze the fluidization characteristics and separation performance of the *** results showed that there was upflow and downflow in the fluidized *** upflow was mainly composed of water flow,followed by light and heavy particles;on the other hand,the downflow was caused by the backflow of heavy particles that settled at the inclined *** addition,the light particles that settled at the inclined section could return to the rising water flow under the action of secondary *** the water velocity,separation time,and secondary gas velocity increased,the comprehensive separation efficiency of fine coal in the fluidized bed improved,while the value decreased as the feed quantity *** also indicated the order of importance for these four factors,i.e.,water velocity,separation time,feed quantity,and secondary gas velocity,on ***,the comprehensive separation efficiency of 0.1-1 mm fine coal varied significantly with various factors,while that of∼0.1 mm and 1-3 mm fine coal was always at a low *** the latter case,the classification process of the size fraction was significantly better than the separation process in the fluidized *** optimal working conditions,an IILSFB was used to separate the fine coal(0.1-1 mm).The yield of clean coal was 37.95% with an ash content of 12.11%,and the possible error was 0.085 g/cm^(3),indicating that the IILSFB had good separation performance for 0.1-1 mm fine coal.

关键词： Inflatable-inclined liquid-solid fluidized bed Fine coal separation Fluidization Separation efficiency Secondary gas velocity Size fraction

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Flow-field analysis of a continuous gas-solid separation fluidized bed equipped with a moving scraper

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Particuology 2021年第4期19卷 45-55页

作者： bo lv Xiaowei Deng Chaojun Fang Xiangnan Zhu College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Henan Key Laboratory for Green and Efficient Mining&Comprehensive Utilization of Mineral Resources Henan Polytechnic UniversityJiaozuo 454000China School of Chemical&Environmental Engineering Shandong University of Science&TechnologyQingdao 266590China

Continuous gas-solid separation fluidized beds are one of the most widely used practical operation units for the dry separation of coal in China,particularly in Northwest China,and they can effectively promote the efficient and clean utilization of raw *** a continuous gas-solid separation fluidized bed,the bed flow field is the concrete manifestation of the fluidization ***,the complexity of the flow field increases under the action of a moving *** this study,a combination of computational fluid dynamics(CFD)simulations and experimental measurements was used to study the changes in the flow field of a fluidized *** results showed that when the scraper moved,the local flow field(mainly characterized by the movement of medium particles)near the scraper was affected not only by the common airflow or bubbles,but also by the lateral driving force of the *** the scraper speed was v_(l)<6.0 cm/s,it reduced the frequency of the formation of large bubbles and alleviated the random fluctuation of the nearby particle collision stress signals,which improved the fluidization stability of the ***,the movement of the scraper affected the global flow *** flow field shifted to the right near the scraper,with the direction of the scraper movement,while the flow field exhibited a leftward trend on the surface of the bed,accompanied by some vortices,in the middle and lower parts of the ***,the critical height of the area,directly affected by the scraper,increased from 52 to 54 mm with an increase in its operating speed from v_(l)=2.96 cm/s to v_(l)=4.44 cm/s,*** provides a theoretical basis for further understanding the hydrodynamic characteristics of fluidized beds.

关键词： Simulation analysis Moving scraper Flow-field Particle collision pressure Hydrodynamic characteristics

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Particle mixing behavior of fine coal in density control of gas-solid separation fluidized bed

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Particuology 2020年第3期18卷 76-87页

作者： bo lv Zhenfu Luo Yanhong Fu bo Zhang Xingzong Qin Xiangnan Zhu College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education China University of Mining&TechnologyXuzhou 221116China School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116China School of Chemical&Environmental Engineering Shandong University of Science&TechnologyQingdao 266590China

In a gas-solid separation fluidized bed,mixing of fine coal is necessary to achieve a suitable bed density to enable effective separation of low rank *** the basis of a variety of mixture models,a gas-solid separation fluidized bed was judged,where fine coal particles of 0.6-1.0mm were uniformly mixed with magnetite ***-speed dynamic camera technology was combined with a slump-sampling method to study the mixing process of the fine coal in the fluidized *** results showed that limitations of the fluidized bed structure cause the mixing process to be dominated by lateral diffusion and supplemented by axial *** diffusion was mainly achieved through the ascension of bubbles,whereas lateral diffusion was determined by the bursting action of the gas bubbles at the surface of the bed and the undulating characteristics of the *** effective lateral diffusion coefficient increased exponentially with gas velocity but had no strong relationship with the bed *** the feed point moved toward the center,fine coal began to diffuse to both sides,which shortened the time for the bed density stabilization from 20 to 5 *** bed density of the layer was stabilized at approximately 1.75 g/*** separation efficiency of the gas-solid separation fluidized bed containing binary mixtures was more obvious for 6-50 mm raw coal,with a probable error E of 0.16.

关键词： Gas-solid separation fluidized bed Density control Fine coal Diffusion behavior Separation process

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针对附件的高校课程作业评分系统开发

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福建电脑 2024年第8期40卷 70-74页

作者：向训文吕波马驰惠州学院计算机科学与工程学院广东惠州516000

高校课程教学中的许多作业都是以Word、PDF、视频、压缩包等附件形式提交的。对这些作业的评分、成绩统计需要花费大量的时间。为优化附件类课程作业的评分流程,本文设计了一个评分系统,首先将收集到的作业附件提取到本地,然后使用本地... 详细信息

高校课程教学中的许多作业都是以Word、PDF、视频、压缩包等附件形式提交的。对这些作业的评分、成绩统计需要花费大量的时间。为优化附件类课程作业的评分流程,本文设计了一个评分系统,首先将收集到的作业附件提取到本地,然后使用本地应用程序快速打开和查阅,将Word文件转换成PDF文件,将当前班级所有批次作业导出到一个Excel文件,以方便成绩统计。测试的结果表明,该系统可以显著提高附件类课程作业评分、成绩统计的效率。

关键词：课程作业附件评分成绩统计

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Channel selection against electrode shift enables robust myoelectric control without retraining

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Science China(Technological Sciences) 2021年第8期64卷 1653-1662页

作者： lv bo HE JiaYuan SHENG XinJun DING Han ZHU XiangYang State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China Department of Systems Design Engineering Faculty of EngineeringUniversity of WaterlooWaterlooN2L 3G1Canada

Myoelectric controlled interfaces driven by muscle activities have achieved good performance in ideal conditions and showed many potential medical-related and industrial ***,in practical applications,the performance could be drastically degraded due to the electrode(sensor)shift,which is inevitable in donning and doffing the *** this study,we presented a novel channel selection method against electrode shift for robust pattern-recognition based myoelectric *** proposed method was evaluated on twenty-four subjects,including twenty-two able-bodied subjects and two amputees,and compared with two traditional channel selection methods,i.e.,uniform selection(UNI)and sequential feature selection(SFS).We demonstrated that the offline error rates of the proposed method were significantly lower than those of the other two methods(P<0.05),and its online performance in shift conditions was comparable to that in ideal *** outcomes benefit the practical applications of robust myoelectric controlled interfaces.

关键词： myoelectric control high-density electrodes channel selection electrode shift surface electromyography

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