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Asian Herpetological Research 2018年第4期9卷 240-249页

作者： Qiucheng LIU Tongliang WANG Xiaofei ZHAI jichao WANG Ministry of Education Key Laboratory for Tropical Island Ecology College of Life Sciences Hainan Normal University

Anuran calls are usually species-specific and therefore valued as a tool for species identification. Call characteristics are a potential honest signal in sexual selection because they often reflect male body size. Polypedates megacephalus and P. mutus are two sympatric and morphologically similar tree frogs, but it remains unknown whether their calls are associated with body size. In this study, we compared call characteristics of these two species and investigated any potential relationships with body size. We found that P. megacephalus, males produced six call types which consisting of three distinct notes, while P. mutus males produced five types consisting of two types of notes. Dominant frequency, note duration, pulse duration, and call duration exhibited significant interspecific differences. In P. megacephalus, one note exhibited a dominant frequency that was negatively correlated with body mass, snout-vent length, head length, and head width. In P. mutus, the duration of one note type was positively correlated with body mass and head width. These differences in call characteristics may play an important role in interspecific recognition. Additionally, because interspecific acoustic variation reflects body size, calls may be relevant for sexual selection. Taken together, our results confirmed that calls are a valid tool for distinguishing between the two tree-frog species in the field.

关键词： body size call characteristics Polypedates sexual selection

Functionality analysis of an urban water supply network after strong earthquakes

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Earthquake Engineering and Engineering Vibration 2021年第2期20卷 291-302页

作者： Li jichao Shang Qingxue Hou Guanjie Li Quanwang Wang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Department of Civil Engineering Tsinghua UniversityBeijing 100084China

An urban water supply network(WSN)is a crucial lifeline system that helps to maintain the normal functioning of modern ***,the hydraulic analysis of a significantly damaged WSN that suffers from pipe breaks or leaks remains *** this paper,a probability-based framework is proposed to assess the functionality of WSNs in the aftermath of powerful *** serviceability of the WSN is quantified by using a comprehensive index that considers nodal water flow and nodal *** index includes a coefficient that reflects the relative importance of these two *** demand reduction(DR)method,which reduces the water flow of nodes while preventing the negative pressure of nodes,is *** difference between the negative pressure elimination(NPE)method and the DR method is discussed by using the example of a WSN in a medium-sized city in *** functionality values of the WSN are 0.76 and 0.99 when nodal pressure and nodal demands are used respectively as the index of system serviceability at an intensity level that would pertain to an earthquake considered to occur at a maximum *** the intensity of ground motion is as high as 0.4 g,the DR method requires fewer samples than the NPE method to obtain accurate *** NPE method eliminates most of the pipes,which may be unrealistic.

关键词： water supply network system serviceability hydraulic analysis negative pressure elimination benchmark city

AAV mediated carboxyl terminus of Hsp70 interacting protein overexpression mitigates the cognitive and pathological phenotypes of APP/PS1 mice

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Neural Regeneration Research 2025年第1期20卷 253-264页

作者： Zhengwei hu Jing Yang Shuo Zhang Mengjie Li Chunyan Zuo Chengyuan Mao Zhongxian Zhang Mibo Tang Changhe Shi Yuming Xu Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina Academy of Medical Sciences of Zhengzhou University ZhengzhouHenan ProvinceChina NHC Key Laboratory of Prevention and treatment of Cerebrovascular Diseases The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina Henan Key Laboratory of Cerebrovascular Diseases The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina Institute of Neuroscience Zhengzhou UniversityZhengzhouHenan ProvinceChina Sino-British Research Centre for Molecular Oncology National Centre for International Research in Cell and Gene TherapySchool of Basic Medical SciencesAcademy of Medical SciencesZhengzhou UniversityZhengzhouHenan ProvinceChina Department of Gerontology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina

The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control *** this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s *** used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse *** overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated *** also alleviated the concentration of microglia and astrocytes around *** APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin *** of HSP70 and HSP40,which have functional relevance to CHIP,were also *** nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of *** research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 ***,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.

关键词： adeno-associated virus Alzheimer’s disease APP/PS1 mice carboxyl terminus of Hsp70 interacting protein gene therapy

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区域医疗系统抗震韧性综述

哈尔滨工业大学学报 2025年第1期57卷 1-12页

作者：裴顺顺翟长海胡杰结构工程灾变与控制教育部重点实验室(哈尔滨工业大学) 哈尔滨150090 土木工程智能防灾减灾工业和信息化部重点实验室(哈尔滨工业大学) 哈尔滨150090

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通... 详细信息

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通系统的安全性、应急响应能力、多系统的整合与协作,有效评估区域医疗系统的抗震韧性水平,并提出科学的改进建议,对建设韧性城乡具有重要的理论意义。本文通过梳理国内外文献,阐明了区域医疗系统韧性的概念和内涵,总结了地震后短期应急和长期修复两个阶段韧性评估的重点,归纳了现有区域医疗系统韧性的评估框架,从医院集群系统、面向医疗的交通系统、应急医疗服务系统和医疗-交通耦合系统4个方面阐述了现有评估方法。区域医疗系统韧性的研究旨在提高其面对灾害时的抵抗性、短期适应性和长期恢复性,这些研究对于满足紧急和日常的医疗需求以及指导灾后恢复具有重要意义。目前区域医疗系统抗震韧性的研究取得了一些进展,但仍然存在一些挑战,本文最后展望了未来的研究方向。

关键词：区域医疗系统单体医院交通系统抗震韧性功能评估恢复时间

Influence of oscillation strain on the dynamic mechanical relaxation of a La-based metallic glass

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Science China(Technological Sciences) 2023年第11期66卷 3309-3316页

作者： LIANG ShuYi ZHANG LangTing WANG YunJiang PINEDA E QIAO jichao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Department of Physics Institute of Energy TechnologiesUniversitat Politècnica de Catalunya–BarcelonaTechBarcelona 08019Spain Innovation Center NPU-ChongqingChongqing 401135China

Dynamic mechanical relaxation processes,particularly secondary relaxation processes,are closely related to the mechanical and physical properties of metallic *** the effect of oscillation strain amplitude on the secondary relaxation of a typical Labased metallic glass was studied using the dynamic mechanical analysis *** apparent activation energy of theβrelaxation is shown to increase with the oscillation strain *** it changes from 0.02%to 0.16%,the activation energy increases from 0.73 to 0.96 ***,the intensity of theβrelaxation shifts toward high ***,the apparentβrelaxation is found to be sensitive to the physical aging below the glass transition *** findings suggest a correlation between the inelastic deformation and the relaxation behavior of amorphous metals.

关键词： metallic glass dynamic mechanical analysis internal friction βrelaxation oscillation amplitude

The Self-induced Unsteadiness of Tip Leakage Flow in an Axial Low-Speed Compressor with Single Circumferential Casing Groove

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Journal of Thermal Science 2013年第6期22卷 565-572页

作者： DU Juan LI jichao WANG Kai LIN Feng NIE Chaoqun Institute of Engineering Thermophysics Chinese Academy of Sciences Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences

Numerical investigation on the self-induced unsteadiness of tip leakage flow(TLF) for an axial low-speed compressor with smooth wall and six single grooved casings are presented. A ten-passage numerical scheme is used to solve the unsteady Reynolds averaged Navier-Stokes(URANS) equations. It is found that the single grooves at various axial locations could have a large impact on the self-induced unsteadiness and the stall margin improvement(SMI) of compressor. The trend of SMI with groove center location demonstrates that the groove located near the mid of blade tip chord generates the best SMI. The worst groove is located about 20% Cax after the blade leading edge. The root-mean-squre of static pressure(RMSP) contours at 99.5% span and fast Fourier transform for the static pressure traces recorded in the tip clearance region for each casing are analyzed. The results demonstrate that the single groove location not only affects the oscillating strength but also the frequency of the unsteady tip leakage flow. At the near-stall point of smooth casing, the self-induced unsteadiness of TLF is enhanced most by the best grooved casing for SMI. While, the self-induced unsteadiness disappears when the worst groove for SMI is added. The characteristic frequency of TLF is about 0.55 blade passing frequency(BPF) with smooth casing. The frequency components become complicated as the single groove moves from the leading edge to the trailing edge of the blade.

关键词： Tip leakage flow unsteadiness circumferential groove stall margin improvement

Dual stability enhancement mechanisms of axial-slot casing treatment in a high-speed mixed-flow compressor with various tip clearances

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Chinese Journal of Aeronautics 2021年第4期34卷 19-31页

作者： Qianfeng ZHANG Juan DU jichao LI Ming ZHAO Hongwu ZHANG Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300072China

The influence of Axial-Slot Casing Treatment(ASCT)on the performance and stability enhancement mechanisms of ASCT were experimentally and numerically investigated in a highspeed mixed-flow compressor under three different tip *** simulations showed the compressor stalled through end-wall stall route,*** spike stall inception originating from rotor tip region,which was validated by dynamical *** the ASCT was applied,greater than 20%of Stall Margin Improvement(SMI)could be achieved for the compressor under each tip clearance *** streamwise velocity contours and flow structures in the tip region and axial slots were deeply analyzed to explore how the so called‘‘suction and injection effects"generated by the ASCT manipulate tip clearance flow and enhance the stability of compressor under different tip *** was found that the dominant stability enhancement mechanisms of ASCT varies with tip clearance size for the mixed-flow compressor.(A)For the small tip clearance,the dominant mechanism of stability enhancement is the blockage reduction generated in the blade passage by the suction effect of ASCT.(B)For the large tip clearance,the injection effect of the ASCT is the dominant mechanism of stability enhancement with ASCT,which plays the leading role in delaying the spillage of incoming/tip leakage flow interface at the rotor Leading Edge(LE)plane.

关键词： Aerodynamic stability Casing treatment Compressor Numerical simulation Stability enhancement

Genetically encoded X-ray cellular imaging for nanoscale protein localization

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National Science Review 2020年第7期7卷 1218-1227页

作者： huating Kong jichao Zhang Jiang Li Jian Wang Hyun-Joon Shin Renzhong Tai Qinglong Yan Kai Xia Jun hu Lihua Wang Ying Zhu Chunhai Fan Bioimaging Center Shanghai Synchrotron Radiation FacilityZhangjiang Laboratory Shanghai Advanced Research Institute Chinese Academy of Sciences Division of Physical Biology CAS Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied Physics Chinese Academy of Sciences Canadian Light Source Inc. University of Saskatchewan Pohang Accelerator Laboratory POSTECH School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and Shanghai Key Laboratory for Nucleic Acids Chemistry and NanomedicineInstitute of Molecular Medicine Renji Hospital School of Medicine Shanghai Jiao Tong University

Spatial resolution defines the physical limit of microscopes for probing biomolecular localization and interactions in cells. Whereas synchrotron-based X-ray microscopy(XRM) represents a unique approach for imaging a whole cell with nanoscale resolution due to its intrinsic nanoscale resolution and great penetration ability, existing approaches to label biomolecules rely on the use of exogenous tags that are multi-step and error-prone. Here, we repurpose engineered peroxidases as genetically encoded X-ray-sensitive tags(GXET) for site-specific labeling of protein-of-interest in mammalian cells. We find that 3,3-diaminobenzidine(DAB) polymers that are in-situ catalytically formed by fusion-expressed peroxidases are visible under XRM. Using this new tag, we imaged the protein location associated with the alteration of a DNA-methylation pathway with an ultra-high resolution of 30 nanometers. Importantly, the excellent energy resolution of XRM enables multicolor imaging using different peroxidase tags. The development of GXET enlightens the way to nanoscopic imaging for biological studies.

关键词： synchrotron-based X-ray microscopy cellular imaging nanoscale protein localization genetically encoded X-ray tags 3,3-diaminobenzidine polymers

Entropy Generation Analysis in a Mixed-Flow Compressor with Casing Treatment

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Journal of Thermal Science 2019年第5期28卷 915-928页

作者： ZHANG Qianfeng DU Juan LI Zhihui LI jichao ZHANG Hongwu Advanced Gas Turbine Laboratory Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Casing treatments(CT) can effectively extend compressors flow ranges with the expense of efficiency penalty. Compressor efficiency is closely linked to loss. Only revealing the mechanisms of loss generation can design a CT with high aerodynamic performance. In the paper, a highly-loaded mixed-flow compressor with tip clearance of 0.4 mm was numerically studied at a rotational speed of 30,000 r/min to reveal the effects of axial slot casing treatment(ASCT) on the loss mechanisms in the compressor. The results showed that both isentropic efficiency and stall margin were improved significantly by the ASCT. The local entropy generation method was used to analyze the loss mechanisms and to quantify the loss distributions in the blade passage. Based on the axial distributions of entropy generation rate, for both the cases with and without ASCT, the peak entropy generation rate increased in the rotor domain and decreased in the stator domain during throttling the compressor. The peak entropy generation in rotor was mainly caused by the tip leakage flow and flow separations near the rotor leading edge for the mixed-flow compressor no matter which casing was applied. The radial distributions of entropy generation rate showed that the reduction of loss in the rotor domain from 0.4 span to the rotor casing was the major reason for the efficiency improved by ASCT. The addition of ASCT exerted two opposite effects on the losses generated in the compressor. On the one hand, the intensity of tip leakage flow was weakened by the suction effect of slots, which alleviated the mixing effect between the tip leakage flow and main flow, and thus reduced the flow losses;On the other hand, the extra losses upstream the rotor leading edge were produced due to the shear effect and to the heat transfer. The aforementioned shear effect was caused by the different velocity magnitudes and directions, and the heat transfer was caused by temperature gradient between the injected flow and the incom

关键词： numerical simulation mixed-flow compressor loss mechanism casing treatment

Crack spacing of unsaturated soils in the critical state

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Chinese Science Bulletin 2009年第12期54卷 2008-2012页

作者： SUN jichao WANG GuangQian SUN QiCheng State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

The cracking mechanism of unsaturated soils due to evaporation is poorly understood, and the magnitude of crack spacing is usually hard to estimate. In this work, cracks were postulated to occur succedently rather than simultaneously, that is, secondary cracks appear after primary cracks as evaporation continues. Formulae of the secondary crack spacing and secondary trend crack spacing were then derived after stress analysis. The calculated spacing values were consistent with the published experimental data. Meanwhile, the effect of the Poisson ratio on the crack spacing was analyzed, which showed that the magnitude of crack spacing was proportional to the Poisson ratio in the range of [0.30, 0.35].

关键词：裂缝间距非饱和土临界状态开裂机理应力分析实验数据蒸发量泊松比