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Angiosperm-wide analysis of fruit and ovary evolution aided by a new nuclear phylogeny supports association of the same ovary type with both dry and fleshy fruits

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Journal of Integrative Plant Biology 2024年第2期66卷 228-251页

作者： Yezi Xiang Taikui Zhang Yiyong Zhao Hongjin Dong hongyi chen Yi Hu Chien-Hsun Huang Jun Xiang Hong Ma State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity and Ecological EngineeringInstitute of Plant BiologyCenter of Evolutionary BiologySchool of Life SciencesFudan UniversityShanghai 200438China Department of Biology Howard Hughes Medical InstituteDuke UniversityDurhamNC 27708USA Department of Biology the Eberly College of Scienceand the Huck Institutes of the Life Sciencesthe Pennsylvania State UniversityUniversity ParkPA 16802USA Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization College of Biology and Agricultural ResourcesHuanggang Normal UniversityHuanggang 438000China

Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and *** we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain *** this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial *** robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and ***,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple *** of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and *** new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversificat

关键词： angiosperm fruit evolution MADS-box molecular clock nuclear phylogeny ovary and fruit developmental genes

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高海拔地区自然莼菜叶经济性状对水环境的响应

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生态学杂志 2024年第6期43卷 1763-1771页

作者：陈弘毅孙梅刘振亚杨航美西南林业大学云南省高原湿地保护修复与生态服务重点实验室昆明650224 西南林业大学国家高原湿地研究中心昆明650224

探究自然莼菜对水环境的响应策略,可以为科学保护莼菜自然群落提供理论依据。本研究以滇西腾冲北海湿地的自然莼菜群落为对象,根据莼菜的生长态势及北海湿地的水环境状况,选择17个采样点,测定莼菜的叶经济性状以及采样点的水环境因子,... 详细信息

探究自然莼菜对水环境的响应策略,可以为科学保护莼菜自然群落提供理论依据。本研究以滇西腾冲北海湿地的自然莼菜群落为对象,根据莼菜的生长态势及北海湿地的水环境状况,选择17个采样点,测定莼菜的叶经济性状以及采样点的水环境因子,检测莼菜叶经济性状与水环境参数间的关系,探讨高海拔地区自然莼菜对水环境的响应策略。结果表明:与100%盖度相比,盖度为60%~70%的莼菜具有更大的叶片面积以及更低的氮、磷、铁和锌质量分数(P<0.05)。水体溶解氧含量、氮体积分数、磷体积分数、铵态氮体积分数以及水温是影响莼菜叶经济性状的主要水环境因子。光合速率与水体溶解氧含量、铵态氮含量以及硝态氮含量呈显著正相关(P<0.05)。叶片厚度与生化需氧量呈显著正相关;叶片面积与水体溶解氧含量、铵态氮含量及水温呈显著正相关,而与生化需氧量、化学需氧量以及高锰酸钾指数呈显著负相关(P<0.05)。莼菜叶片氮质量分数与水体的氮体积分数及水体的铵态氮体积分数呈显著正相关(P<0.05);叶片磷质量分数与水体氮体积分数呈显著正相关,而与水体溶解氧含量、水温呈显著负相关(P<0.05);叶片氮磷比与水体溶解氧含量及铵态氮含量呈显著正相关,而与化学需氧量及高锰酸钾指数呈显著负相关(P<0.05)。其余的莼菜元素质量分数,包括钾、镁、硅、钙、铁、锌,主要与水体的溶解氧含量、水温及水体的氮、磷等营养条件相关。本研究结果为莼菜自然群落的保护提供了科学依据。

关键词：浮叶植物高原湿地叶经济性状微环境生态响应

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基于用户关系管理的高校图书馆数字学术服务重塑

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大学图书馆学报 2024年第3期42卷 49-55页

作者：张更平陈红艺宁子晨慎金花同济大学图书馆上海200092

在数字学术与“人工智能+”融合发展的背景下,高校图书馆面临满足用户即时性、个性化、精细化需求的挑战。本文采用文献调研方法,梳理了图书馆数字学术服务研究现状,并对42所一流大学建设高校的图书馆进行了网站调研。结果显示,我国高... 详细信息

在数字学术与“人工智能+”融合发展的背景下,高校图书馆面临满足用户即时性、个性化、精细化需求的挑战。本文采用文献调研方法,梳理了图书馆数字学术服务研究现状,并对42所一流大学建设高校的图书馆进行了网站调研。结果显示,我国高校图书馆数字学术服务目前总体上处于实践探索期,服务内容和服务方式等方面仍有待大幅提升。为应对这些问题,本文提出了基于用户关系管理理论的服务重塑流程,通过识别需求和动机、构建用户画像、服务设计与创新、实施与监督、馆员培训与发展五个阶段的紧密互动,洞察用户的偏好与需求,提供彰显用户主体性和能动性的数字学术服务,进而提升用户的学习与研究质量。

关键词：高校图书馆数字学术服务用户关系理论服务重塑

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碳排放视角下武汉市土地生态风险时空格局演变

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水土保持研究 2024年第2期31卷 331-341页

作者：韩雨非刘艳中陈勇汪樱张祚陈弘昳谭玉川武汉科技大学资源与环境工程学院武汉430081 中国地质大学公共管理学院武汉430074 华中师范大学公共管理学院武汉430079

[目的]探究土地利用碳排放对土地生态安全的不利影响,揭示不同因素的演变情况。[方法]引入碳足迹压力指数,并结合植被覆盖度、降水距平百分比指数、土壤侵蚀程度和土地利用混合度一同构建土地生态风险评价模型。使用熵权法确定风险指标... 详细信息

[目的]探究土地利用碳排放对土地生态安全的不利影响,揭示不同因素的演变情况。[方法]引入碳足迹压力指数,并结合植被覆盖度、降水距平百分比指数、土壤侵蚀程度和土地利用混合度一同构建土地生态风险评价模型。使用熵权法确定风险指标权重并计算了综合风险指数。最后,利用空间分析方法,探究了武汉市2010年、2015年、2020年土地生态风险及空间集聚效应的时空演化规律。[结果]武汉市生态风险整体呈降低态势但幅度较小,各行政区风险指数差值大,中心城区植被覆盖度低、土地利用混合度低、碳排放压力高、土地生态安全状况堪忧;土地生态风险指数呈较强的空间集聚状态,冷热点集聚程度先增强后减弱,热点主要集中在中心城区和汉南区内。[结论]土地利用碳排放量的激增造成了土地生态风险的进一步加剧和风险来源的多样化,引入碳足迹压力指数能更全面地评估区域土地生态风险情况,为降低土地生态风险提供依据。

关键词：土地生态风险碳排放空间数据分析武汉市

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基于深度滤波的高精度视差图研究

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北京测绘 2024年第5期38卷 649-654页

作者：孙萍唐硕陈红艺深圳大学物理与光电学院广东深圳518061

针对由于激光雷达扫描特性所造成的点云拖尾及遮挡区域的歧义投影问题,提出了一种基于深度滤波的视差图像滤波算法,对非结构化的点云数据进行处理分析。首先,利用迭代几何编码代价体(IGEV)计算出双目深度估计视差图;然后将点云投影到对... 详细信息

针对由于激光雷达扫描特性所造成的点云拖尾及遮挡区域的歧义投影问题,提出了一种基于深度滤波的视差图像滤波算法,对非结构化的点云数据进行处理分析。首先,利用迭代几何编码代价体(IGEV)计算出双目深度估计视差图;然后将点云投影到对应的彩色图像得到投影视差图,以双目深度估计视差图作为引导图像,在对应的像素位置上对点云投影图进行一致性比较。由于激光雷达在近距离表现不佳,本文还创造性地提出了区分前景和背景的阈值判断方法。与德国卡尔斯鲁厄理工学院和美国芝加哥丰田理工学院(KITTI)计算机视觉算法评测数据集进行了对比实验,其实验结果表明,与KITTI算法相比,该算法在检测精度上提升了0.72%,验证了本文方法的有效性。

关键词：点云滤波立体匹配激光雷达图像处理

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An evaluation model for smart grids in support of smart cities based on the Hierarchy of Needs Theory

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Global Energy Interconnection 2023年第5期6卷 634-644页

作者： Hongyu Lin Wei Wang Yajun Zou hongyi chen School of Management Harbin Institute of TechnologyHarbin 150000P.R.China Global Energy Interconnection Development and Cooperation Organization Beijing 100031P.R.China Mechanical and Industrial Engineering Department University of MinnesotaDuluth MN55812USA

Smart cities depend highly on an intelligent electrical networks to provide a reliable,safe,and clean power supplies.A smart grid achieves such aforementioned power supply by ensuring resilient energy delivery,which presents opportunities to improve the cost-effectiveness of power supply and minimize environmental impacts.A systematic evaluation of the comprehensive benefits brought by smart grid to smart cities can provide necessary theoretical fundamentals for urban planning and construction towards a sustainable energy ***,most of the present methods of assessing smart cities do not fully take into account the benefits expected from the smart *** comprehensively evaluate the development levels of smart cities while revealing the supporting roles of smart grids,this article proposes a model of smart city development needs from the perspective of residents’needs based on Maslow’s Hierarchy of Needs theory,which serves the primary purpose of building a smart *** classifying and reintegrating the needs,an evaluation index system of smart grids supporting smart cities was further constructed.A case analysis concluded that smart grids,as an essential foundation and objective requirement for smart cities,are important in promoting scientific urban management,intelligent infrastructure,refined public services,efficient energy utilization,and industrial development and *** optimization suggestions were given to the city analyzed in the case include strengthening urban management and infrastructure constructions,such as electric vehicle charging facilities and wireless coverage.

关键词： Smart city Smart grid Evaluation index system Hierarchy of needs Benefits of smart grid

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Hollow sphere of heterojunction(NiCu)S/NC as advanced anode for sodium-ion battery

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Journal of Energy Chemistry 2023年第7期82卷 248-258,I0006页

作者： hongyi chen Pengfei Lv Pengfu Tian Shiyue Cao Shengjun Yuan Qiming Liu Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072HubeiChina

Metal sulfide is considered as a potential anode for sodium-ion batteries(SIBs),due to the high theoretical capacity,strong thermodynamic stability and ***,their cycle capacity and rate performance are limited by the excessive expansion rate and low intrinsic ***,heterogeneous hollow sphere NiS-Cu_(9)S_(5)/NC(labeled as(NiCu)S/NC)based on Oswald ripening mechanism was prepared through a simple and feasible *** a structural perspective,the hollow structure provides an expansion buffer and raises the electrochemical active *** terms of electron/ion during the cycles,Na^(+)storage mechanism is optimized by NiS/Cu_(9)S_(5)heterogeneous interface,which increases the storage sites and shortens the migration path of Na^(+).The formation of built-in electric field strengthens the electron/ion *** on the first principle calculations,it is further proved the formation of heterogeneous interfaces and the direction of electron *** the anode for SIBs,the synthesized(NiCu)S/NC delivers high reverse capacity(559.2 mA h g^(-1)at 0.5 A g^(-1)),outstanding rate performance(185.3 mA h g^(-1)at 15 A g^(-1)),long-durable stability(342.6 mA h g^(-1)at 4 A g^(-1)after 1500cycles,150.0 m A h g^(-1)at 10 A g^(-1)after 20,000 cycles with 0.0025%average attenuation rate).The matching cathode electrode Na_(3)V_(2)(PO_(4))_(3)/C is assembled with(NiCu)S/NC for the full-battery that achieves high energy density(253.7 W h kg^(-1))and reverse capacity(288.7 mA h g^(-1)).The present work provides a distinctive strategy for constructing electrodes with excellent capacity and stability for SIBs.

关键词： Hollow structure Heterogeneous interface First principle calculations Sodium-ion batteries

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AC loss mitigation for high temperature superconducting coils in wireless power transfer

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Superconductivity 2023年第2期6卷 6-24页

作者： hongyi chen Hongye Zhang Research Center for Graph Computing Zhejiang LabHangzhouChina Department of Electrical and Electronic Engineering University of ManchesterManchester M139PLUnited Kingdom

With the rapid development of high temperature superconducting(HTS)technology,second generation(2G)HTS materials have become a promising alternative to traditional conductive materials in the power transmission ***,the topic of using HTS materials in wireless power transfer(WPT)systems for electric vehicles(EVs)has attracted widespread attention in the background of net zero *** virtually zero DC resistance and superior current‐carrying capacity,HTS materials can achieve high quality factor and power density in the WPT resonant circuits compared to conventional metals,e.g.,***,the optimal working frequency for the conventional WPT system is relatively high in the order of kilohertz *** coils working at high frequencies could generate high AC losses,reducing the overall power transfer efficiency(PTE)and increasing the cooling *** order to improve the PTE of HTS‐WPT systems,the AC loss mitigation methods for different HTS coil topologies have been investigated in this paper by varying the inter‐turn gap and tape *** HTS coil structures,namely the spiral coil,the solenoid coil and the double pancake(DP)coil,have been studied with a 2D axisymmetric multi‐layer numerical model based on the H‐formulation,and the simulation results have been validated by the published experimental *** general loss characteristics,loss distributions in each turn,as well as magnetic flux densities have been analysed in detail for three types of HTS ***,the impact of these two loss reduction methods on the WPT performance has also been *** have shown that increasing the inter‐turn gap and tape width can effectively reduce the AC power losses and increase the PTE of the HTS‐WPT *** spiral coil demonstrates the highest AC power loss reduction effect and PTE while maintaining a stable level of magnetic *** paper is believed to deepen the understanding of superconducting WPT and provi

关键词： Wireless Power Transfer(WPT) High temperature superconductor Loss reduction Inter‐turn gap Tape width

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火星陨石NWA 13763矿物岩石学特征及其岩浆演化

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桂林理工大学学报 2024年第2期44卷 204-216页

作者：张晋瑜陈宏毅谢兰芳高旭凯芦思洁宋文磊桂林理工大学行星地质演化广西高校重点实验室广西桂林541006 桂林理工大学广西隐伏金属矿产勘查重点实验室广西桂林541006 桂林理工大学地球科学学院广西桂林541006 北京大学造山带与地壳演化教育部重点实验室北京100871 北京大学地球与空间科学学院北京100871 西北大学大陆动力学国家重点实验室西安710069 西北大学地质学系西安710069

NWA 13763陨石为一块新发现的辉长质辉玻无球粒火星陨石,辉长结构和次辉绿结构,主要矿物组成为辉石(45.1%,其中普通辉石36.1%,易变辉石9.0%)和斜长石(42.3%,几乎全部熔长石化),次要矿物组成为富硅相(5.1%)、橄榄石(2.7%)、磷酸盐矿物(2.... 详细信息

NWA 13763陨石为一块新发现的辉长质辉玻无球粒火星陨石,辉长结构和次辉绿结构,主要矿物组成为辉石(45.1%,其中普通辉石36.1%,易变辉石9.0%)和斜长石(42.3%,几乎全部熔长石化),次要矿物组成为富硅相(5.1%)、橄榄石(2.7%)、磷酸盐矿物(2.4%)、钛铁矿(2.2%),含极少量钛磁铁矿和斜锆石。陨石中广泛发育“铁橄榄石+富硅相”二相后成合晶和“钙铁辉石+铁橄榄石+富硅相”三相后成合晶。辉石主晶核部贫铁富镁(Fs_(24.7-55.3)),边部富铁贫镁(Fs_(61.5-86.1));熔长石成分均一(An_(44.4-54.6Ab43.7-53.7));铁橄榄石(Fa_(84.5-97.7))全部以细粒状分布于后成合晶中。由钛铁氧化物固溶体计算得到岩浆结晶的氧逸度(FMQ)f_(O_(2))=-0.045,钛铁矿结晶温度约975℃。利用全岩成分和MELTS程序模拟计算表明,NWA 13763陨石的母岩浆液相线温度范围可能为1190~830℃,矿物结晶顺序由早到晚可能为:培长石→拉长石→橄榄石→单斜辉石→中长石→磷酸盐矿物→钛铁矿→富硅残余相。

关键词：火星陨石 NWA 13763 辉玻无球粒陨石岩石学矿物学岩浆演化

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High-Level Security Dimension Evaluation of Blockchain BaaS System and Key Technology

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China Communications 2024年第6期21卷 176-191页

作者： chen Wanfa Zheng Qing’an chen Shuzhen Fu hongyi chen Liang Fujian Police College Fuzhou 350007China Computer Science and Information Security Management Department Fujian Police CollegeFuzhou 350007China Fujian Province Key Laboratory for Digital Network Crime Supervision and Prevention Fuzhou 350007China Beijing University of Posts and Telecommunications Beijing 100876China Fujian Provincial Prison Administration Fuzhou 350002China

In recent years,blockchain technology integration and application has gradually become an important driving force for new technological innovation and industrial *** blockchain technology and applications are developing rapidly,the emerging security risks and obstacles have gradually become *** can still find security issues in blockchain systems and conduct attacks,causing increasing losses from network attacks every *** response to the current demand for blockchain application security detection and assessment in all industries,and the insufficient coverage of existing detection technologies such as smart contract detectiontechnology,this paper proposes a blockchain core technology security assessment system model,and studies the relevant detection and assessment key technologies and systems.A security assessment scheme based on a smart contract and consensus mechanism detection scheme is *** the underlying blockchain architecture supports the traceability of detection results using super ***,the functionality and performance of the system were tested,and the test results show that the model and solutions proposed in this paper have good feasibility.

关键词： blockchain security consensus mechanis smart contract

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