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Development of a subchannel code for blockage accidents of LMFRs based on the 3D fuel rod model

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Nuclear Science and Techniques 2022年第3期33卷 30-44页

作者： Xiao luo lian-Kai Cao Wen-pei Feng Hong-li Chen School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China

To predict the thermal-hydraulic(T/H)parameters of the reactor core for liquid-metal-cooled fast reactors(LMFRs),especially under flow blockage accidents,we developed a subchannel code called *** code uses a time-dependent,four-equation,singlephase flow model together with a 3D heat conduction model for the fuel rods,which is solved by numerical methods based on the finite difference method with a staggered *** to the local effect of the blockage on the flow field,low axial flow,increased forced crossflow,and backflow *** more accurately simulate this problem,we implemented a robust and novel solution *** verified the code with a low-flow(~0.01 m/s)and large-scale blockage *** the preliminary validation,we compared our results with the experimental data of the NACIE-UP BFPS blockage test and the KIT19ROD blockage *** results revealed that KMC-FB has sufficient solution accuracy and can be used in future flow blockage analyses for LMFRs.

关键词： Subchannel method Code development Blockage accident liquid-metal-cooled fast reactor

The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons

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Neural Regeneration Research 2025年第1期20卷 209-223页

作者： Shi-Yan Sun lingyun Nie Jing Zhang Xue Fang Hongmei luo Chuanhai Fu Zhiyi Wei Ai-Hui Tang Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Brain Function and DiseaseMinistry of Education Key Laboratory for Membrane-less Organelles and Cellular DynamicsDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina CAS Center for Excellence in Molecular Cell Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Neurobiology School of Life SciencesSouthern University of Science and TechnologyShenzhenGuangdong ProvinceChina Brain Research Center Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina

Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and ***-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains *** this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative ***,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic *** of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and *** down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive *** together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.

关键词： actin cytoskeleton dendrite KANK1 KIF21A microtubule spine morphology spine synaptic plasticity talin1

Resolving the developmental mechanisms of cardiac microthrombosis of SARS-CoV-2 based on single-cell transcriptome analysis

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Science China life Sciences 2025年第1期68卷 103-115页

作者： Xizi luo Nan Zhang Yuntao liu Beibei Du Xuan Wang Tianxu Zhao Bingqiang liu Shishun Zhao Jiazhang Qiu Guoqing Wang State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Basic MedicineJilin University State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Veterinary MedicineJilin University College of Mathematics Jilin University Bioinformatic Lab School of MathematicsShandong University Department of Cardiology China-Japan Union HospitalJilin University

The coronavirus disease 2019（COVID-19） outbreak caused by the severe acute respiratory syndrome coronavirus-2（SARS-CoV-2） developed into a global health emergency. Systemic microthrombus caused by SARS-CoV-2 infection is a common complication in patients with COVID-19. Cardiac microthrombosis as a complication of SARS-CoV-2 infection is the primary cause of cardiac injury and death in patietns with severe COVID-19. In this study, we performed single-cell sequencing analysis of the right ventricular free wall tissue from healthy donors,patients who died during the hypercoagulable period of characteristic coagulation abnormality（CAC）, and patients who died during the fibrinolytic period of CAC. We collected 61,187 cells enriched in 24 immune cell subsets and 13 cardiac-resident cell subsets. We found that in the course of SARS-CoV-2 infected heart microthrombus, MYO1EhighRASGEF1Bhighmonocyte-derived macrophages promoted hyperactivation of the immune system and initiated the extrinsic coagulation pathway by activating chemokines CCL3, CCL5. This series of events is the main cause of cardiac microthrombi following SARS-CoV-2 infection. In a SARS-CoV-2 infected heart microthrombus, excessive immune activation is accompanied by an increase in cellular iron content, which in turn promotes oxidative stress and intensifies intercellular competition. This induces cells to alter their metabolic environment, resulting in increased sugar uptake via the glycosaminoglycan synthesis pathway. In addition, high levels of reactive oxygen species generated by elevated iron levels promote increased endogenous malondialdehyde synthesis in a subpopulation of cardiac endothelial cells. This exacerbates endothelial cell dysfunction and exacerbates the coagulopathy process.

关键词： SARS-CoV-2 cardiac microthrombosis immune hyperactivation cell competition

极端洪水导致的外源营养和水位升高对黑藻(Hydrillaverticillata)、附着藻类和水质的影响

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湖泊科学 2025年第1期37卷 184-193,I0018,I0019页

作者：罗东黄文强丁明明黎磊南昌大学鄱阳湖环境与资源利用教育部重点实验室南昌大学生命科学学院南昌330031 江西鄱阳湖湿地保护与恢复国家长期科研基地江西鄱阳湖湿地生态系统国家定位观测研究站南昌330031 鄱阳湖流域生态水文监测研究江西省重点实验室南昌330002

极端洪水显著地影响水生植物的生存环境,带来的连锁效应可能是导致沉水植物大规模衰退的原因之一。极端洪水导致的外源营养、水位升高是影响沉水植物生长和繁殖的重要因素,因此以湖泊代表性沉水植物黑藻(Hydrilla verticillata)为对象,... 详细信息

极端洪水显著地影响水生植物的生存环境,带来的连锁效应可能是导致沉水植物大规模衰退的原因之一。极端洪水导致的外源营养、水位升高是影响沉水植物生长和繁殖的重要因素,因此以湖泊代表性沉水植物黑藻(Hydrilla verticillata)为对象,通过模拟研究探讨极端洪水事件导致的水位波动(水位在短时间内升高)及营养脉冲(营养物质在短时间内增加)对沉水植物、附着藻类和水体理化性质的影响。设置4种水位及营养盐负荷情景:对照(水位保持在75 cm)、水位由75 cm逐步上升到150 cm+氮磷输入、水位由75 cm急剧上升到150 cm+氮磷输入以及水位保持75 cm+氮磷输入,其中后3项处理氮、磷输入量相同,90 d内同步监测了浮游植物、附着藻类以及水体氮、磷浓度的变化。结果表明,对照组中,黑藻雌株相较于雄株个体更大,而极端降水(水位急剧上升)处理下,雄株的相对生长速率(RGR)、根生物量和繁殖器官数均大于雌株,表现出明显的性别二态性。雌性个体对水位波动(水位急剧上升和逐步上升)和营养脉冲的响应比雄性个体响应更为敏感。水位急剧上升和逐步上升均抑制了黑藻根生物量积累、RGR和主枝数,但株高、地上生物量和繁殖生物量保持稳定,水位急剧上升同时抑制了附着藻类的生长。营养脉冲提高了上覆水氮浓度,促进浮游植物和周丛藻类生长,对黑藻地上部分、根和繁殖生物量均有显著抑制作用。实验设置的水位范围内,水位升高对黑藻的地上部分生长及繁殖的影响不明显,而氮、磷输入增加及水位波动的联合作用抑制了其地上部分生物量及繁殖输出,因此营养脉冲增强了水位升高对黑藻的影响效应。由此可以认为,极端洪水事件引起的水位波动叠加营养脉冲的复合效应可能会对沉水植物产生明显的抑制作用,随着未来降水强度和频率增加,水生态系统将受到较大的冲击。

关键词：浅水湖泊沉水植物水位波动富营养化气候变化有性繁殖

Adaptive Finite Element Modeling of Marine Controlled-Source Electromagnetic Fields in Two-Dimensional General Anisotropic Media

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Journal of Ocean University of China 2013年第1期12卷 1-5页

作者： li Yuguo luo Ming pei Jianxin Key Lab of Submarine Geosciences and Prospecting Techniques of Ministry of Education Ocean University of China

In this paper, we extend the scope of numerical simulations of marine controlled-source electromagnetic (CSEM) fields in a particular case of anisotropy (dipping anisotropy) to the general case of anisotropy by using an adaptive finite element approach. In comparison to a dipping anisotropy case, the first order spatial derivatives of the strike-parallel components arise in the partial differential equations for generally anisotropic media, which cause a non-symmetric linear system of equations for finite element modeling. The adaptive finite element method is employed to obtain numerical solutions on a sequence of refined unstructured triangular meshes, which allows for arbitrary model geometries including bathymetry and dipping layers. Numerical results of a 2D anisotropic model show both anisotropy strike and dipping angles have great influence on the marine CSEM responses.

关键词： adaptive finite elements marine CSEM general anisotropy

A binocular vision-based UAVs autonomous aerial refueling platform

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Science China(Information Sciences) 2016年第5期59卷 232-238页

作者： Haibin DUAN Han li Qinan luo Cong ZHANG Cong li pei li Yimin DENG Bio-inspired Autonomous Flight Systems (BAFS) Research Group School of Automation Science and Electrical Engineering Beihang University (BUAA)

Unmanned aerial vehicles(UAVs) are highly focused and widely used in various domains, and the capability of autonomous aerial refueling(AAR) becomes increasingly important. Most of the research in this area concerns the verification of the algorithms while the experiments are conducted on the ground. In this work, in order to verify the vision system designed for boom approach AAR, an integrated platform is built and tested. The platform consists of a tanker UAV, a receiver UAV and a ground station. The pictures of the marker on the receiver UAV are captured by the binocular vision system on the tanker UAV and then used for flight control and boom control. Performance and feasibility of the platform are demonstrated by the real out-door flight tests, and the experimental results verified the feasibility and effectiveness of our developed binocular vision-based UAVs AAR.

关键词： unmanned aerial vehicles(UAVs) autonomous aerial refueling(AAR) boom approach binocular vision visual measurement

Enhanced mechanical property by introducing bimodal grains structures in Cu-Ta alloys fabricated by mechanical alloying

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Journal of Materials Science & Technology 2024年第5期172卷 104-112页

作者： Ningyu li Yongqin Chang Mingyang li Yuxiang Chen Xinrui luo Shichao pei Fan Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China

Dispersion-strengthened copper alloys can achieve ultra-high strength,but usually at the expense of *** this study,a strategy for overcoming strength-ductility tradeoffof Cu alloys is realized through the introduction of bimodal grains ***-Ta alloys with only 0.5 at.%Ta content were successfully prepared by mechanical alloying combined with spark plasm *** samples prepared by one-step and two-step ball milling methods are named as Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ),*** microstructural characterizations revealed that ultra-fine equiaxed grains with uniformly dispersed Ta precipitates were obtained in the Cu-Ta *** strength of 377 MPa for yield strength together with elongation of∼8%was obtained in Cu-Ta(Ⅰ).Bimodal grains structures composed of fine-grain zones and coarse-grain zones were successfully introduced into Cu-Ta(Ⅱ)by a two-step ball milling approach,and both yield strength(463 MPa)and elongation(∼15%)were significantly synergistic *** hardness values of both Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)were almost kept nearly constant with the increase of annealing time,and the softening temperatures of Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)are 1018 and 1013℃,reaching 93.9%and 93.5%T m of pure Cu(1083℃),*** reveals that the Cu-0.5 at.%Ta alloys exhibit excellent thermal stability and exceptional softening *** nanoclusters with semi-coherent structures play an essential role in enhancing the strength and microstructural stability of *** structures are beneficial to the activation of back stress strengthening and the initiation and propagation of microcracks,thus obtaining the extraordinary combination of strength and *** study provides a new way to fabricate dispersion-strengthened Cu alloys with high strength,high elongation,excellent thermal stability and softening resistance,which have potential application value in the field of the future fusion reactor.

关键词： Cu-Ta alloy Mechanical alloying Ta precipitates Bimodal structures Mechanical property

Extracting embedded messages using adaptive steganography based on optimal syndrome-trellis decoding paths

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Digital Communications and Networks 2022年第4期8卷 455-465页

作者： Jialin li Xiangyang luo Yi Zhang pei Zhang Chunfang Yang Fenlin liu State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou450000China

Privacy protection is the key to maintaining the Internet of Things(IoT)communication *** is an important way to achieve covert communication that protects user data *** technology is the key to checking steganography security,and its ultimate goal is to extract embedded *** methods cannot extract under known cover *** this end,this paper proposes a method of extracting embedded messages under known cover ***,the syndrome-trellis encoding process is ***,a decoding path in the syndrome trellis is obtained by using the stego sequence and a certain parity-check matrix,while the embedding process is simulated using the cover sequence and parity-check *** the decoding path obtained by the stego sequence and the correct parity-check matrix is optimal and has the least distortion,comparing the path consistency can quickly filter the coding parameters to determine the correct matrices,and embedded messages can be extracted *** proposed method does not need to embed all possible messages for the second time,improving coding parameter recognition *** experimental results show that the proposed method can identify syndrome-trellis coding parameters in stego images embedded by adaptive steganography quickly to realize embedded message extraction.

关键词： Information security Image steganography STC coding Parameter recognition

Unique landslides (loess slide-flows) induced by an extreme rainstorm in 2018 on the Loess Plateau: A new geological hazard and erosion process

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International Journal of Sediment Research 2023年第2期38卷 228-239页

作者： li luo Wen-Zhao Guo pei Tian Yi-li liu Shao-Kun Wang Jia-Wei luo State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/College of Water Resources and Architectural Engineering Northwest Agriculture and Forestry University State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province Central China Normal University

Currently, the vegetation has recovered well in most areas of the Loess Plateau in China, and soil erosion has significantly decreased. However, the heavy rainfall event in July 2018 triggered many instances of a unique type of loess landslides(i.e., slide-flows) on the gully-slopes with vegetation recovery in the Nanxiaohegou Basin on the Loess Plateau. This rainfall event was unusual and was a persistent heavy rainfall. The accumulated rainfall from 24 June to 10 July was 232.2 mm, which comprised 42% of the mean annual rainfall. A loess slide-flow is characterized by combining two movement types of the slide and flow. The loess slide-flows first slide on the gully-slopes and then turn into long run-out earthflows moving downstream, delivering vast amounts of sediment to the river. The average landslide erosion rates were 110.8-134.9 kg/m2. These loess slide-flows generally did not occur individually but in groups,which were characterized by large numbers, high density, small scale, and shallow depth. The changes of vegetation characteristics and soil characteristics both had a significant impact on the scale of the landslides. Grass with high coverage had an adverse effect on the occurrence of shallow landslides. The adverse hydrological effects of the plant may offset the weak root reinforcement. Loess slide-flows have become a new geological hazard and erosion process on the Loess Plateau. Loess slide-flows are a prominent ecological and environmental problem after vegetation restoration, and more attention should be paid to loess slide-flows in the future.

关键词： Loess plateau Landslide Soil erosion Vegetation Rainfall