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Anthrax lethal toxin and tumor necrosis factor-a synergize on intestinal epithelia to induce mouse death

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Protein & Cell 2024年第2期15卷 135-148页

作者： Xinhe Gao Teng Teng yifei liu Tingting Ai Rui Zhao Yilong Fu Peipei Zhang Jiahuai Han Yingying Zhang State Key Laboratory of Cellular Stress Biology School of Life SciencesFaculty of Medicine and Life SciencesXiamen UniversityXiamen 361102China Research Unit of Cellular Stress of CAMS Xiang'an Hospital of Xiamen UniversityCancer Research Center of Xiamen UniversitySchool of MedicineFaculty of Medicine and Life SciencesXiamen UniversityXiamen 361102China Laboratory Animal Center Faculty of Medicine and Life SciencesXiamen UniversityXiamen 361102China

Bacillus anthracis lethal toxin(LT)is a determinant of lethal anthrax.Its function in myeloid cells is required for bacterial dissemination,and LT itself can directly trigger dysfunction of the cardiovascular system.The interplay between LT and the host responses is important in the pathogenesis,but our knowledge on this interplay remains limited.Tumor necrosis factor-a(TNF-a)is a pleiotropic pro-inflammatory cytokine induced by bacterial infections.Since LT accumulates and cytokines,predominantly TNF,amass during B.anthracis infection,co-treatment of TNF+LT in mice was used to mimic in vivo conditions for LT to function in inflamed hosts.Bone marrow transplantation and genetically engineered mice showed unexpectedly that the death of intestinal epithelial cells(IECs)rather than that of hematopoietic cells led to LT+TNF-induced lethality.Inhibition of p38a mitogen-activated protein kinase(MAPK)signaling by LT in IECs promoted TNF-induced apoptosis and necroptosis of IECs,leading to intestinal damage and mouse death.Consistently,p38a inhibition by LT enhanced TNF-mediated cell death in human colon epithelial HT-29 cells.As intestinal damage is one of the leading causes of lethality in anthrax patients,the IEC damage caused by LT+TNF would most likely be a mechanism underneath this clinical manifestation and could be a target for interventions.

关键词： lethal toxin TNF p38a intestinal epithelial cell cell death

Gyro-Landau-fluid simulations of impurity effects on ion temperature gradient driven turbulence transport

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Plasma Science and Technology 2024年第1期26卷 8-15页

作者：刘逸飞李继全 Southwestern Institute of Physics Chengdu 610041People’s Republic of China

The effects of impurities on ion temperature gradient(ITG)driven turbulence transport in tokamak core plasmas are investigated numerically via global simulations of microturbulence with carbon impurities and adiabatic electrons.The simulations use an extended fluid code(ExFC)based on a four-field gyro-Landau-fluid(GLF)model.The multispecies form of the normalized GLF equations is presented,which guarantees the self-consistent evolution of both bulk ions and impurities.With parametric profiles of the cyclone base case,well-benchmarked ExFC is employed to perform simulations focusing on different impurity density profiles.For a fixed temperature profile,it is found that the turbulent heat diffusivity of bulk ions in a quasi-steady state is usually lower than that without impurities,which is contrary to the linear and quasilinear predictions.The evolutions of the temperature gradient and heat diffusivity exhibit a fast relaxation process,indicating that the destabilization of the outwardly peaked impurity profile is a transient state response.Furthermore,the impurity effects from different profiles can obviously influence the nonlinear critical temperature gradient,which is likely to be dominated by linear effects.These results suggest that the improvement in plasma confinement could be attributed to the impurities,most likely through adjusting both heat diffusivity and the critical temperature gradient.

关键词： gyro-Landau-fluid simulation impurity effects ion temperature gradient mode turbulence transport

Exciting lattice oxygen of nickel–iron bi-metal alkoxide for efficient electrochemical oxygen evolution reaction

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Journal of Energy Chemistry 2024年第1期88卷 194-201,I0005页

作者： Saihang Zhang Senchuan Huang Fengzhan Sun Yinghui Li Li Ren Hao Xu Zhao Li yifei liu Wei Li Lina Chong Jianxin Zou National Engineering Research Center of Light Alloy Net Forming&State Key Laboratory of Metal Matrix Composites Center of Hydrogen ScienceSchool of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Laboratory of Advanced MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEM and State Key Laboratory of Molecular Engineering of PolymersCollege of Chemistry and MaterialsFudan UniversityShanghai 200433China

High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage systems.The electro-oxidation of water to oxygen plays a crucial role in such energy conversion technologies.Herein,we report a robust method for the synthesis of a bimetallic alkoxide for efficient oxygen evolution reaction(OER)for alkaline electrolysis,which yields current density of 10 mA cm^(-2)at an overpotential of 215 mV in 0.1 M KOH electrolyte.The catalyst demonstrates an excellent durability for more than 540 h operation with negligible degradation in activity.Raman spectra revealed that the catalyst underwent structure reconstruction during OER,evolving into oxyhydroxide,which was the active site proceeding OER in alkaline electrolyte.In-situ synchrotron X-ray absorption experiment combined with density functional theory calculation suggests a lattice oxygen involved electrocatalytic reaction mechanism for the in-situ generated nickel–iron bimetal-oxyhydroxide catalyst.This mechanism together with the synergy between nickel and iron are responsible for the enhanced catalytic activity and durability.These findings provide promising strategies for the rational design of nonnoble metal OER catalysts.

关键词： Oxygen evolution reaction Nickel-iron bi-metal alkoxide Lattice oxygen-mediated reaction mechanism Alkaline electrolysis Electrocatalysts

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植物次生代谢产物生物合成基因簇研究进展

植物学报 2024年第1期59卷 134-143页

作者：朱璐袁冲刘义飞湖北中医药大学武汉430074

植物产生的次生代谢产物为人类提供了丰富的药物、香料和工业原料。随着分子生物学和基因组学研究的快速发展,目前已解析了多种植物的次生代谢产物生物合成基因簇(BGCs)。这为我们快速获取目标产物的生物合成通路和发掘新颖的天然产物... 详细信息

植物产生的次生代谢产物为人类提供了丰富的药物、香料和工业原料。随着分子生物学和基因组学研究的快速发展,目前已解析了多种植物的次生代谢产物生物合成基因簇(BGCs)。这为我们快速获取目标产物的生物合成通路和发掘新颖的天然产物开辟了新路径。该文重点围绕植物次生代谢产物生物合成基因簇的定义和特点、基本结构模型与演化以及调控机制等进行综述,以期为相关研究提供理论依据和借鉴。

关键词：次生代谢产物生物合成基因簇基因簇调控基因簇特征

中国省域旅游业碳排放效率及驱动因子时空非平稳性研究

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中国生态旅游 2024年第1期14卷 113-130页

作者：甘畅刘依飞王凯武汉轻工大学管理学院武汉430048 湖南师范大学旅游学院长沙410081

加快绿色低碳转型已成为中国旅游业高质量发展的重要锚点。基于2004—2019年中国省际面板数据,综合运用基于非期望产出的超松弛值测算(Super-SBM)模型、时间核密度分析、空间自相关模型和空间马尔科夫链勾勒旅游业碳排放效率的时空演化... 详细信息

加快绿色低碳转型已成为中国旅游业高质量发展的重要锚点。基于2004—2019年中国省际面板数据,综合运用基于非期望产出的超松弛值测算(Super-SBM)模型、时间核密度分析、空间自相关模型和空间马尔科夫链勾勒旅游业碳排放效率的时空演化格局,进一步采用时空地理加权回归模型探析旅游业碳排放效率驱动因子的时空非平稳性。结果表明:(1)研究期内,中国省域旅游业碳排放效率呈现波动上升的演化态势,但总体仍处于中等水平;其核密度分布形态大致经历了“双峰-三峰-双峰”的演化过程。(2)中国省域旅游业碳排放效率的空间关联特征显著,L-L空间关联类型的省份主要位于中西部地区;在马尔科夫概率转移矩阵中,旅游业碳排放效率类型较稳定,短期内难以实现跨越式转移,各地区旅游业碳排放效率类型转移的概率具有明显的空间依赖性,且存在“俱乐部收敛”现象。(3)不同驱动因子对旅游业碳排放效率的作用方向和强度均存在显著的时空非平稳性,城镇化水平和环境规制强度的促进作用逐渐增强,华东地区的旅游业碳排放效率主要由环境规制强度、旅游业技术水平驱动,而华北地区则主要由产业结构、环境规制强度、旅游业技术水平等因素驱动。

关键词：旅游业碳排放效率时空非平稳性同伴效应俱乐部收敛时空地理加权回归绿色低碳转型

基于北斗卫星通信技术的远洋船舶通信自动化控制系统

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电子设计工程 2024年第5期32卷 150-155页

作者：刘逸飞交通运输部上海打捞局上海200090

远洋船舶通信自动化控制过程中,易受到数据中频信号干扰的影响,导致控制效率较低。为此,提出基于北斗卫星通信技术的远洋船舶通信自动化控制系统。基于基本功能需求,选择手持终端机与时钟控制器型号,采用北斗卫星通信技术对基带信号进... 详细信息

远洋船舶通信自动化控制过程中,易受到数据中频信号干扰的影响,导致控制效率较低。为此,提出基于北斗卫星通信技术的远洋船舶通信自动化控制系统。基于基本功能需求,选择手持终端机与时钟控制器型号,采用北斗卫星通信技术对基带信号进行降阶处理,以抑制数据中频信号扰动,并引入调制信号对通信数据进行捕捉,结合无线通信程序的设计,完成远洋船舶通信自动化控制。系统测试结果表明,在发送时钟频率范围为25~150 MHz时,所提系统的通信时延均在0.4 ms以下,能够有效提高通信控制效率。

关键词：北斗卫星通信技术远洋船舶通信自动化控制调制信号

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舰船通信网络不完整节点数据模糊采集算法

电子设计工程 2024年第1期32卷 170-174页

作者：刘逸飞交通运输部上海打捞局上海200090

基于改进数据采集结果冗余的目的,研究舰船通信网络不完整节点数据模糊采集算法。根据所定义的节点传输数据的概率,并结合聚类阈值,对不完整节点数据进行模糊聚类,选定聚类簇中心。采用平滑参数对舰船通信网络数据中的冗余数据进行处理... 详细信息

基于改进数据采集结果冗余的目的,研究舰船通信网络不完整节点数据模糊采集算法。根据所定义的节点传输数据的概率,并结合聚类阈值,对不完整节点数据进行模糊聚类,选定聚类簇中心。采用平滑参数对舰船通信网络数据中的冗余数据进行处理,并提取不完整节点的数据特征向量。构建目标函数,通过求解最优路径来实现数据采集,同时考虑比特序列开销值,输出最优解。测试结果表明,采用提出的方法对不完整节点数据进行模糊采集时,数据集的平均冗余度为22,具备较为理想的数据采集效果。

关键词：通信网络不完整节点模糊采集数据冗余度

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外源亚精胺对枣树抗高温胁迫的调节机制

北方园艺 2024年第4期 14-20页

作者：刘羿飞陈奇凌吴翠云塔里木大学园艺与林学学院南疆特色果树高效优质栽培与深加工技术国家地方联合工程实验室新疆阿拉尔843300 新疆农垦科学院林园研究所新疆石河子832061

以‘早熟优’枣树为试材,设置常温喷蒸馏水(HckW)、高温喷蒸馏水(HW)、常温喷1 mmol·L^(-1)亚精胺(HckS)、高温喷1 mmol·L^(-1)亚精胺(HS)4个处理,研究了亚精胺对枣树抗高温胁迫的调节机制,以期为枣树优质栽培提供参考依据。结果表明... 详细信息

以‘早熟优’枣树为试材,设置常温喷蒸馏水(HckW)、高温喷蒸馏水(HW)、常温喷1 mmol·L^(-1)亚精胺(HckS)、高温喷1 mmol·L^(-1)亚精胺(HS)4个处理,研究了亚精胺对枣树抗高温胁迫的调节机制,以期为枣树优质栽培提供参考依据。结果表明:高温胁迫下的枣树生长指标增长速度显著低于常温对照和喷施亚精胺处理的枣树;高温处理的枣树光合色素含量显著降低,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和丙二醛(MDA)、可溶性蛋白质、可溶性糖、脯氨酸(Pro)含量均显著升高;高温下喷施亚精胺(Spd)的枣树叶片内源脱落酸(ABA)含量先升后降;内源腐胺(Put)、精胺(Spm)、Spd含量上升明显,在处理7 d后基本达到最高值后开始下降。喷施亚精胺之后缓解了枣树对高温胁迫的响应。

关键词：高温胁迫枣亚精胺内源激素渗透调节物质

Semi-supervised Counting of Grape Berries in the Field Based on Density Mutual Exclusion

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Plant Phenomics 2023年第4期5卷 825-835页

作者： Yanan Li Yuling Tang yifei liu Dingrun Zheng School of Computer Science and Engineering School of Artificial IntelligenceWuhan Institute of TechnologyWuhan 430205China Hubei Key Laboratory of Intelligent Robot Wuhan Institute of TechnologyWuhan 430073China

Automated counting of grape berries has become one of the most important tasks in grape yield prediction.However,dense distribution of berries and the severe occlusion between berries bring great challenges to counting algorithm based on deep learning.The collection of data required for model training is also a tedious and expensive work.To address these issues and cost-effectively count grape berries,a semi-supervised counting of grape berries in the field based on density mutual exclusion(CDMENet)is proposed.The algorithm uses VGG16 as the backbone to extract image features.Auxiliary tasks based on density mutual exclusion are introduced.The tasks exploit the spatial distribution pattern of grape berries in density levels to make full use of unlabeled data.In addition,a density difference loss is designed.The feature representation is enhanced by amplifying the difference of features between different density levels.The experimental results on the field grape berry dataset show that CDMENet achieves less counting errors.Compared with the state of the arts,coefficient of determination(R^(2))is improved by 6.10%,and mean absolute error and root mean square error are reduced by 49.36%and 54.08%,respectively.The code is available at.

关键词： Grape mutual backbone