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台风影响、股票回报和公司反应:中国视角

中国科学技术大学学报 2024年第2期54卷 18-34,I0005页

作者：邵丽香郑智中国科学技术大学管理学院统计与金融系安徽合肥230026

研究了台风灾害对中国A股上市公司股票收益的影响和公司管理层面对此类极端气候灾害的反应。基于2003~2018年中国A股上市公司的样本,我们发现台风袭击对中国股市带来了显著的负面影响.首先,采用事件研究法直接检验台风袭击造成的异常收... 详细信息

研究了台风灾害对中国A股上市公司股票收益的影响和公司管理层面对此类极端气候灾害的反应。基于2003~2018年中国A股上市公司的样本,我们发现台风袭击对中国股市带来了显著的负面影响.首先,采用事件研究法直接检验台风袭击造成的异常收益。同时,根据规模和价值因子将股票分成不同的投资组合,考察台风影响对于不同因子的敏感度.最后,采用多期双差分模型研究了企业管理层面对极端灾害时的反应。研究发现,相较于距离灾区较远的企业,邻近灾区的企业更倾向于在灾后采取一定的预防措施,包括降低流动债务占总债务的比率和增加长期借款融资占比。此外,随着袭击次数的增加,公司的过度反应会逐渐消失,而这种过度反应的合理性需要进一步研究。

关键词：台风资产定价中国股票市场公司反应

不同灌溉水盐度下土壤真菌群落对生物炭施用的响应

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环境科学 2024年第1期45卷 520-529页

作者：郑志玉郭晓雯闵伟石河子大学农学院石河子832003

咸水灌溉可缓解干旱区淡水资源短缺的问题,但是长期咸水灌溉会破坏土壤真菌群落结构.为缓解盐分带来的危害,采用生物炭作为土壤改良剂,以改善土壤真菌群落结构.为探究施用生物炭对盐渍化土壤真菌群落结构多样性的影响,设置两个灌溉水盐... 详细信息

咸水灌溉可缓解干旱区淡水资源短缺的问题,但是长期咸水灌溉会破坏土壤真菌群落结构.为缓解盐分带来的危害,采用生物炭作为土壤改良剂,以改善土壤真菌群落结构.为探究施用生物炭对盐渍化土壤真菌群落结构多样性的影响,设置两个灌溉水盐度:0.35 dS·m^(-1)(淡水)和8.04 dS·m^(-1)(咸水),在每个灌溉水盐度下,设置2个生物炭施用水平:0 t·hm^(-2)(不施)和3.7 t·hm^(-2)(施用).高通量测序结果表明,与淡水灌溉相比,咸水灌溉增加了真菌群落物种多样性,降低了真菌群落物种丰富度;在咸水灌溉条件下施加生物炭降低了土壤真菌群落物种多样性和物种丰富度.各处理土壤的优势菌门为:子囊菌门、被孢菌门、担子菌门、壶菌门、球囊菌门和罗兹菌门,优势菌属为:赤霉菌属、Sarocladium、毛壳菌属、镰刀菌属和葡萄穗霉属.与淡水灌溉相比,咸水灌溉显著增加担子菌门和壶菌门的相对丰度,显著降低子囊菌门和罗兹菌门的相对丰度.咸水灌溉的条件下施用生物炭显著增加子囊菌门和Sarocladium的相对丰度,显著降低担子菌门、毛壳菌属和镰刀菌属的相对丰度.LEfSe差异分析表明,在不施生物炭的条件下,咸水灌溉降低真菌群落潜在生物标志物数量,而咸水灌溉的条件下施用生物炭增加真菌群落潜在生物标志物数量.以上结果表明,施用生物炭能够改善盐渍化土壤环境和真菌群落结构,为干旱区合理咸水灌溉和培肥土壤提供理论依据.

关键词：灌溉水盐度生物炭真菌 LEfSe分析高通量测序

Acollaborative target tracking algorithm formultiple UAVs with inferior tracking capabilities

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Frontiers of Information Technology & Electronic Engineering 2021年第10期22卷 1334-1350页

作者： zhi zheng Shuncheng CAI College of Computer and Cyber Security Fujian Normal UniversityFuzhou 350117China

Target tracking is one of the hottest topics in the field of drone research.In this paper,we study the multiple unmanned aerial vehicles(multi-UAV)collaborative target tracking problem.We propose a novel tracking method based on intention estimation and effective cooperation for UAVs with inferior tracking capabilities to track the targets that may have agile,uncertain,and intelligent motion.For three classic target motion modes,we first design a novel trajectory feature extraction method with the least dimension and maximum coverage constraints,and propose an intention estimation mechanism based on the environment and target trajectory features.We propose a novel Voronoi diagram,called MDA-Voronoi,which divides the area with obstacles according to the minimum reachable distance and the minimum steering angle of each UAV.In each MDA-Voronoi region,the maximum reachable region of each UAV is defined,the upper and lower bounds of the trajectory coverage probability are analyzed,and the tracking strategies of the UAVs are designed to effectively reduce the tracking gaps to improve the target sensing time.Then,we use the Nash Q-learning method to design the UAVs’collaborative tracking strategy,considering factors such as collision avoidance,maneuvering constraints,tracking cost,sensing performance,and path overlap.By designing the reward mechanism,the optimal action strategies are obtained as the control input of the UAVs.Finally,simulation analyses are provided to validate our method,and the results demonstrate that the algorithm can improve the collaborative target tracking performance for multiple UAVs with inferior tracking capabilities.

关键词： Collaborative target tracking Intent estimation MDA-Voronoi diagram Multi-UAV Inferior

二轮到期后进城落户农民群体的承包地:延包逻辑与方案选择

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经济体制改革 2024年第1期 80-87页

作者：姚志郑志浩长江大学经济与管理学院湖北荆州434023 西北农林科技大学经济管理学院陕西杨凌712100

随着农村土地二轮承包到期、延包时点的临近,进城落户群体的承包地延包处置问题亟需解决。理论分析与访谈调查显示:到期延包处置包含固有的现实依据、效率逻辑与产权归属逻辑;在未来延包时点,主要可以配给直接顺延、有偿退出、无偿退回... 详细信息

随着农村土地二轮承包到期、延包时点的临近,进城落户群体的承包地延包处置问题亟需解决。理论分析与访谈调查显示:到期延包处置包含固有的现实依据、效率逻辑与产权归属逻辑;在未来延包时点,主要可以配给直接顺延、有偿退出、无偿退回、有偿使用四种方案;到期后全部直接顺延进城落户群体的承包地可能引发无地人群的不满,而有偿退出存在着标准难统一等问题;直接无偿收回进城落户群体的承包地可能会成为大部分村庄的主要选择,原因是受到户籍变动、公平心理与收入差异的影响;有偿使用方案得到了超过半数的访谈农户支持。事实上,进城落户群体的农村承包地权利处置问题实质上是“农村土地承包经营权人主体资格”问题,是对承包权的下属权利如成员权、继承权、退出权等土地产权理论边界的拓展与深化,也是对中国农地产权改革理论内容的细化与丰富。

关键词：二轮土地承包到期后进城落户群体承包地延包方案

乡村人才振兴与乡村经济高质量发展——基于高校毕业生返乡就业分析

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经济问题 2024年第2期 91-97页

作者：郑直孔令海长春师范大学数学学院吉林长春130032 南京林业大学马克思主义学院江苏南京210037

乡村振兴战略的实施促进乡村经济逐渐走向高质量发展的道路。在这个过程中,高校毕业生的返乡就业成为推动乡村经济发展的重要力量,为乡村的经济发展注入了新的活力。乡村人才振兴和乡村经济高质量发展是相互促进、相辅相成的,为乡村经... 详细信息

乡村振兴战略的实施促进乡村经济逐渐走向高质量发展的道路。在这个过程中,高校毕业生的返乡就业成为推动乡村经济发展的重要力量,为乡村的经济发展注入了新的活力。乡村人才振兴和乡村经济高质量发展是相互促进、相辅相成的,为乡村经济的持续发展提供了强有力的支撑。只有实现两者的协同发展,才能更好地推动乡村振兴战略的实施,实现农村经济社会的全面发展。只有通过培养和引进大量优秀人才,才能推动乡村产业升级、科技创新和文化繁荣,从而实现乡村振兴战略的目标。此外,乡村人才的培养和引进还能为乡村振兴全面发展提供坚实保障。高校毕业生可以通过自己的行动和影响力,改变村民们对乡村振兴的认识和态度,激发他们的积极性和创造力。

关键词：乡村人才振兴乡村经济高质量发展高校毕业生

One-pot synthesis of FeNxC as efficient catalyst for high-performance zinc-air battery

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Journal of Energy Chemistry 2022年第3期31卷 100-106,I0004页

作者： Yang Li Kuanda Xu Qi Zhang zhi zheng Shunning Li Qinghe Zhao Can Li Cheng Dong Zongwei Mei Feng Pan Shixue Dou School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055GuangdongChina Institute for Superconducting and Electronic Materials University of WollongongWollongongNSW 2522Australia College of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018ZhejiangChina

Rechargeable zinc-air batteries(ZAB)with a high theoretical energy density of 1086 Wh kg^(-1),have received tremendous research attention.However,the practical application of ZABs is still limited by high polarization and poor energy efficiency(low power density)due to the sluggish 4 electrons(e^(-))/oxygen(O_(2))kinetics over the air electrode.Here,a noble-metal-free Fe Nx C electrocatalyst is developed via a onepot approach,which provides a high density of the oxygen reduction reaction(ORR)active site and facilitates the ORR kinetics.Accordingly,the as-assembled Zn-air battery displayed a low charge–discharge voltage gap of 0.71 V at 10 m A cm^(-2),a remarkable peak power density as high as 181.2 m W cm^(-2),as well as the long-term durability for hundreds of hours,among the top level of those reported previously.Our work provides a major boost for the practical application of Zn-air battery in the future.

关键词： FeNxC Oxygen reduction reaction Zinc-air battery

One‑Step Gas-Solid‑Phase Diffusion‑Induced Elemental Reaction for Bandgap‑Tunable Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI Thin Film Solar Cells

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Nano-Micro Letters 2023年第4期15卷 261-271页

作者： Erchuang Fan Manying Liu Kangni Yang Siyu Jiang Bingxin Li Dandan Zhao Yanru Guo Yange Zhang Peng Zhang Chuantian Zuo Liming Ding zhi zheng Key Laboratory of Micro‑Nano Materials for Energy Storage and Conversion of Henan Province College of Chemical and Materials EngineeringInstitute of Surface Micro and Nano MaterialsXuchang UniversityXuchang 461000People’s Republic of China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001People’s Republic of China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190People’s Republic of China

Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step gas-solid-phase diffusioninduced reaction to fabricate a series of bandgap-tunable Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI bilayer films due to the atomic diffusion effect for the first time.By designing and regulating the sputtered Cu/Ag/Bi metal film thickness,the bandgap of Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI could be reduced from 2.06 to 1.78 eV.Solar cells with the structure of FTO/TiO_(2)/Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI/carbon were constructed,yielding a champion power conversion efficiency of 2.76%,which is the highest reported for this class of materials owing to the bandgap reduction and the peculiar bilayer structure.The current work provides a practical path for developing the next generation of efficient,stable,and environmentally friendly photovoltaic materials.

关键词： Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI Elemental reaction Bandgap tuning Solar cells Gas-solid phase

FRP-混凝土组合式护栏防护重型车辆撞击的能力

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重庆大学学报 2024年第4期47卷 51-63页

作者：郑植杨波袁佩耿波重庆大学土木工程学院重庆400045 招商局重庆交通科研设计院有限公司桥梁工程结构动力学国家重点实验室重庆400067

为提高低等级混凝土护栏防护重型车辆的能力,设计了3种不同构造形式的复合材料护板,分别设置在混凝土护栏表面形成组合式护栏。建立车-护栏精细化有限元模型,通过与实车碰撞试验结果对比,验证了有限元模型的可靠性。考虑撞击力、碰撞角... 详细信息

为提高低等级混凝土护栏防护重型车辆的能力,设计了3种不同构造形式的复合材料护板,分别设置在混凝土护栏表面形成组合式护栏。建立车-护栏精细化有限元模型,通过与实车碰撞试验结果对比,验证了有限元模型的可靠性。考虑撞击力、碰撞角度、车辆轨迹、货厢尾部抬高、车辆动态外倾值、车辆外倾角6个评价指标,对比分析了3种方案护栏的防车撞性能。结果表明,在整体式货车撞击下,3种方案护栏均能顺利引导车辆转向,不带阻坎的方案一的各主要指标均优于其他方案,防护能力最优;在拖挂式货车撞击下,方案一的护栏导向与阻挡性能依然良好,驶出角仅为0.75°;改造后的组合式护栏防护能量达到650 kJ,防护能力是改造前的4倍。

关键词：组合式护栏碰撞仿真防车撞能力复合材料

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KLF16 promotes pancreatic adenocarcinoma cell proliferation and migration by positively regulating SMAD6

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World Journal of Gastrointestinal Oncology 2022年第11期14卷 2157-2169页

作者： Wei Mi zhi zheng Jiong-Di Lu Shu-Quan Duan Jie Zhang Hai-Qiao Zhang Yi-Xuan Ding Jie Yin Feng Cao Jun Zhang Fei Li Department of General Surgery Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of General Surgery Xuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Digestive Minimally Invasive Surgery The Second Affiliated Hospital of Baotou Medical CollegeBaotou 014030Inner Mongolia Autonomous RegionChina Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

BACKGROUND Pancreatic adenocarcinoma(PAAD)is a cancerous tumor with an extremely poor 5-year survival rate.The exploration of biomarkers for the diagnosis and treatment of PAAD is crucial in clinical practice.Krüppel-like factors(KLFs)are involved in a variety of biological functions in cells.According to multiple studies,KLF16 behave as an oncogene in prostate,breast and gastric cancers.However,no research has been done on the significance of KLF16 in PAAD.AIM To explore the molecular mechanisms of KLF16 in PAAD.METHODS KLF16 was identified in the tumor specimens and normal tissues by GEPIA database and verified by quantitative real-time PCR(qRT-PCR).Knockdown or exogenous expression of KLF16,combined with in vitro and in vivo assays,was performed to show the functional significance of KLF16.The molecular mechanism of KLF16 was demonstrated by qRT-PCR,western blotting,immunoprecipitation assay and flow cytometry.RESULTS We showed that KLF16 was highly expressed in PAAD patients based on the GEPIA database.KLF16 silencing suppressed while KLF16 overexpression promoted the malignant function of PAAD cells.Based on RNA sequencing,we discovered that KLF16 potentiated the expression of SMAD6 in PAAD cells.SMAD6 transcript abundance was increased and positively correlated with KLF16 expression in PAAD samples.In addition,inhibiting SMAD6 was able to mitigate the effects of KLF16 overexpression on PAAD cell processes,suggesting the importance of SMAD6 in the development of KLF16-triggered PAAD.CONCLUSION KLF16/SMAD6 axis might be explored as a therapeutic target for PAAD therapy.

关键词： KLF16 Pancreatic adenocarcinoma SMAD6 Tumorigenesis Therapeutic target