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Adaptive temporal patterns of echolocation and flight behaviors used to fly through varied-sized windows by 2 species of high duty cycle bats

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Current Zoology 2023年第1期69卷 32-40页

作者： jianan Ding Yu Zhang Fujie Han Tingting jiang jiang Feng Aiqing Lin Ying Liu Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchun 130117China College of Life Science Jilin Agricultural UniversityChangchun 130024China Key Laboratory of Vegetation Ecology School of EnvironmentInstitute of Grassland ScienceNortheast Normal UniversityMinistry of EducationChangchun 130024China

As actively sensing animals guided by acoustic information, echolocating bats must adapt their vocal–motor behavior to various environmentsand behavioral tasks. Here, we investigated how the temporal patterns of echolocation and flight behavior were adjusted in 2 species of batswith a high duty cycle (HDC) call structure, Rhinolophus ferrumequinum and Hipposideros armiger, when they flew along a straight corridorand then passed through windows of 3 different sizes. We also tested whether divergence existed in the adaptations of the 2 species. Both *** and R. ferrumequinum increased their call rates by shortening the pulse duration and inter-pulse interval for more rapid spatial samplingof the environment when flying through smaller windows. Bats produced more sonar sound groups (SSGs) while maintaining a stable proportion of calls that made up SSGs during approaches to smaller windows. The 2 species showed divergent adjustment in flight behavior across3 different window sizes. Hipposideros armiger reduced its flight speed to pass through smaller windows while R. ferrumequinum increasedits flight speed. Our results suggest that these 2 species of HDC bats adopt similar acoustic timing patterns for different tasks although theyperformed different flight behaviors.

关键词： echolocating bats environmental clutter flight trajectory sensory adaptation sonar temporal pattern

航空电反推驱动用永磁同步电机振动及强度分析

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电机与控制应用 2020年第9期47卷 44-50页

作者：孙桂林蒋佳楠袁瑞林王培路宋受俊刘卫国西北工业大学自动化学院陕西西安710072 诺丁汉大学工程学院英国诺丁汉NG72RD 陕西航空电气有限责任公司陕西西安710000

电机的模态是分析振动的基础,由固有频率、振型和阻尼比决定。当电机工作时的激振频率与某一阶的固有频率相同或者相近时,会产生共振,导致电机剧烈振动,影响其正常运转。在对应用于航空电反推系统的双通道永磁同步电机PMSM进行三维建模... 详细信息

电机的模态是分析振动的基础,由固有频率、振型和阻尼比决定。当电机工作时的激振频率与某一阶的固有频率相同或者相近时,会产生共振,导致电机剧烈振动,影响其正常运转。在对应用于航空电反推系统的双通道永磁同步电机PMSM进行三维建模之后,将三维模型送入ANSYS Workbench,在ANSYS工作平台上进行电机模态、响应谱分析与冲击响应的仿真。给出了该电机的前6阶次的固有频率和振型,以及在外加响应谱下的电机等效应力与在瞬态冲击下的电机机械结构上的应力分布。

关键词：永磁同步电机模态分析响应谱分析电机振动冲击响应

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制药工程本科毕业设计的教学改革与实践

实验室科学 2023年第6期26卷 231-235页

作者：冯佳朱宏吉赵广荣郭翔海蒋建兰天津大学化工学院天津300072

随着新工科建设的推进,工程教育面临不断地改革和提升,以适应新经济背景下人才发展的需求。毕业设计是培养学生工程实践能力、创新就业能力的重要实践环节,通过产业、设计院、高校三方联盟,在天津大学制药工程专业中探索毕业设计培养的... 详细信息

随着新工科建设的推进,工程教育面临不断地改革和提升,以适应新经济背景下人才发展的需求。毕业设计是培养学生工程实践能力、创新就业能力的重要实践环节,通过产业、设计院、高校三方联盟,在天津大学制药工程专业中探索毕业设计培养的新要求、新模式和评价新办法,建立了新的毕业设计教学模式,培养学生解决“跨界”的“复杂工程问题”,成为复合型制药工程创新人才。

关键词：毕业设计制药工程教学改革

猪链球菌2型通过诱导人脑微血管内皮细胞RPSA蛋白发生相分离促进菌体对细胞的黏附

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中国兽医学报 2024年第5期44卷 966-973页

作者：孙毅刘嘉楠姜合祥李扬李娜李丰阳雷连成吉林大学动物医学学院人兽共患病研究教育部重点实验室吉林长春130062 吉林大学护理学院吉林长春130021

猪链球菌2型(Streptococcus suis serotype 2,SS2)是诱发细菌性脑膜炎的一种人畜共患病原菌,宿主脑微血管内皮细胞(BMEC)是构成血脑屏障(blood-brain barrier, BBB)的主要细胞,也是病原攻击的重要靶细胞。近年发现宿主细胞核糖体蛋白SA(... 详细信息

猪链球菌2型(Streptococcus suis serotype 2,SS2)是诱发细菌性脑膜炎的一种人畜共患病原菌,宿主脑微血管内皮细胞(BMEC)是构成血脑屏障(blood-brain barrier, BBB)的主要细胞,也是病原攻击的重要靶细胞。近年发现宿主细胞核糖体蛋白SA(ribosomal protein SA,RPSA)参与SS2诱发的脑膜炎发病过程,但相关机制仍知之甚少。本研究通过对人脑微血管内皮细胞(human cortical microvessels endothelial cells/D3,HCMEC/D3)RPSA蛋白进行序列分析、相分离能力测定,初步研究了RPSA在SS2感染过程中的作用和机制。结果显示,HCMEC/D3 RPSA具有典型的内部无序区(IDRs)结构域;SS2感染能够诱导RPSA发生相分离,相分离显著增强了细菌对细胞的黏附能力;SS2毒力因子ENO既能够促进RPSA发生相分离,也介导了细菌与细胞的黏附。另外,SS2感染后胞内Ca^(2+)水平升高是促进相分离的关键因素。综上,本研究证实SS2通过提升胞内Ca^(2+)水平,促进RPSA发生相分离,从而增强SS2(ENO)与RPSA的相互作用,导致黏附并进一步引起细胞损伤造成宿主感染。本研究为SS2诱发脑膜炎的认知提供了新思路。

关键词：猪链球菌2型核糖体蛋白SA 相分离烯醇化酶 Ca2+

A comprehensive review of natural products with anti-hypoxic activity

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Chinese Journal of Natural Medicines 2023年第7期21卷 499-515页

作者： LIU Juncai GE Zhen jiang Xiao ZHANG Jingjing SUN jianan MAO Xiangzhao College of Food Science and Engineering Ocean University of ChinaQingdao 266003China Medical College Qingdao Binhai UniversityQingdao 266555China Laboratory for Marine Drugs and Bioproducts Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

Natural products exhibit substantial impacts in the field of anti-hypoxic *** can cause altitude sickness and other negative effect on the ***,coma,exhaustion,vomiting and,in severe cases,death are some of the clinical ***,hypoxia is no longer just a concern in plateau regions;it is also one of the issues that can not be ignored by urban *** review covered polysaccharides,alkaloids,saponins,flavonoids,peptides and traditional Chinese compound prescriptions as natural products to protect against *** active ingredients,effectiveness and mechanisms were *** related anti-hypoxic mechanisms involve increasing the hemoglobin(HB)content,glycogen content and adenosine triphosphate(ATP)content,removing excessive reactive oxygen species(ROS),reducing lipid peroxidation,regulating the levels of related enzymes in cells,protecting the structural and functional integrity of the mitochondria and regulating the expression of apoptosis-related *** comprehensive summaries are beneficial to anti-hypoxic research and provide useful information for the development of anti-hypoxic products.

关键词： Natural products Anti-hypoxia Mechanism Activity

Uniform Distribution Spread-spectrum Modulation Strategy for MMC to Reduce Conducted EMI and Switching Loss

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Chinese Journal of Electrical Engineering 2022年第4期8卷 39-51页

作者： Hui Liu jianan Chen Dong jiang Hong Li Xuejun Pei Wei Sun State Key Laboratory of Advanced Electromagnets Engineering and Technology Huazhong University of Science and TechnologyWuhan 430074China College of Electrical Engineering and Control Science Nanjing University of TechnologyNanjing 211816China School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

Modular multilevel converters(MMCs)have been widely used owing to their superior ***,the rapid switching of power electronics devices causes serious electromagnetic interference(EMI).There are a large number of obvious EMI peaks in the frequency spectrum of the carrier phase-shifted constant-switching-frequency pulse-width modulation(CSFPWM).Spreading the EMI across a wider frequency range can help to reduce the EMI *** this study,we designed a uniform distribution(UD)spread-spectrum modulation technology using the principle of uniform switching frequency distribution and minimum switching loss for *** feasibility is verified by theoretical derivation and ***,the effectiveness of UDPWM in reducing the EMI is verified in experiments with a prototype MMC testbed in the *** with traditional CSFPWM,UDPWM can reduce conducted EMI by 10-20 ***,compared with random PWM(RPWM),UDPWM can improve efficiency and reduce total harmonic distortion(THD)of output voltage and current in MMC.

关键词： MMC conducted EMI carrier phase shift uniform distribution

航空电反推用永磁同步电机余度设计与仿真分析

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微电机 2021年第8期54卷 12-18页

作者：蒋佳楠袁瑞林赵群弼段晓丽宋受俊刘卫国西北工业大学自动化学院西安710072 陕西航空电气有限责任公司西安710000

本文以航空发动机电动反推力装置为应用背景,对永磁同步电机进行了余度设计,采用双绕组电机来代替两个独立的电机,既保证了高可靠性,又大幅度减轻了体积和重量。该电机的特点是只有一套转子,定子铁心上嵌绕着两套独立绕组,形成并联余度... 详细信息

本文以航空发动机电动反推力装置为应用背景,对永磁同步电机进行了余度设计,采用双绕组电机来代替两个独立的电机,既保证了高可靠性,又大幅度减轻了体积和重量。该电机的特点是只有一套转子,定子铁心上嵌绕着两套独立绕组,形成并联余度设计。控制器部分也采用余度思想,设计为双通道结构,热备份工作模式。基于航空发动机电动反推力装置的实际工况,考虑电机的四象限运行状态,并设计了相应的制动电路。结合控制策略,利用Matlab/Simulink对整个系统热备份工作模式进行了仿真,整体上验证了余度设计的可行性。

关键词：永磁同步电机可靠性多余度设计双绕组电机双通道结构

Common Mode EMI Reduction through PWM Methods for Three-Phase Motor Controller

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CES Transactions on Electrical Machines and Systems 2019年第2期3卷 133-142页

作者： Dong jiang jianan Chen Zewei Shen State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhanCO 430074 China

Pulse-width sequences are identified as the determining factor for common-mode(CM)voltage,which together with CM path generate CM *** paper introduces a series of pulse-width modulation(PWM)methods,which are focusing on reducing CM noise of three-phase inverters as motor ***,theoretic analysis and PWM reduction methods of CM voltage for general three-phase two-level inverters are *** results indicate that the realization of CM noise reduction should take switching frequency and loop impedance into consideration together to avoid CM resonant *** regular three-phase two-level inverter is incapable of eliminating CM voltage because of the limitation of ***,optimal PWM methods applied to for advanced topologies can be utilized to eliminate the CM voltage *** typical typologies presented in this paper are three-level inverters and paralleled ***-level inverters can achieve zero-CM output voltage by selecting zero-CM voltage vectors at the expense of power ***,for paralleled inverters,zero-CM PWM method is able to achieve zero CM voltage output,as well as the improved output current harmonics and voltage balancing.

关键词： Common-mode voltage conducted EMI PWM methods paralleled inverters.

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一种模块化组装肽链空间结构的装置

生命的化学 2020年第11期40卷 2109-2112页

作者：彭亚会孙增廷江嘉楠黄显赫李冀宏哈尔滨医科大学生物化学与分子生物学教研室哈尔滨150086

参照蛋白质结构理论参数,设计了一种肽平面教具,可以模块化组装肽链空间结构,为教师及学生提供直观、可操作性强而且可以展示肽平面旋转角度的模型。

关键词：肽平面肽键氨基酸残基肽链空间结构