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Hierarchical detection and tracking for moving targets in underwater wireless sensor networks 被引量:1
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作者 Yudong Li Hongcheng Zhuang +2 位作者 Long Xu Shengquan Li Haibo Lu 《Digital Communications and Networks》 2025年第2期556-562,共7页
It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sens... It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sensor Networks(UWSNs).To this end,this paper investigates the relationship between the Degree of Target Change(DoTC)and the detection period,as well as the impact of individual nodes.A Hierarchical Detection and Tracking Approach(HDTA)is proposed.Firstly,the network detection period is determined according to DoTC,which reflects the variation of target motion.Secondly,during the network detection period,each detection node calculates its own node detection period based on the detection mutual information.Taking DoTC as pheromone,an ant colony algorithm is proposed to adaptively adjust the network detection period.The simulation results show that the proposed HDTA with the optimizations of network level and node level significantly improves the detection accuracy by 25%and the network energy consumption by 10%simultaneously,compared to the traditional adaptive period detection schemes. 展开更多
关键词 Underwater wireless sensor networks The degree of target change Mutual information PHEROMONE Adaptive period
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Dynamic Multi-Target Jamming Channel Allocation and Power Decision-Making in Wireless Communication Networks:A Multi-Agent Deep Reinforcement Learning Approach
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作者 Peng Xiang Xu Hua +4 位作者 Qi Zisen Wang Dan Zhang Yue Rao Ning Gu Wanyi 《China Communications》 2025年第5期71-91,共21页
This paper studies the problem of jamming decision-making for dynamic multiple communication links in wireless communication networks(WCNs).We propose a novel jamming channel allocation and power decision-making(JCAPD... This paper studies the problem of jamming decision-making for dynamic multiple communication links in wireless communication networks(WCNs).We propose a novel jamming channel allocation and power decision-making(JCAPD)approach based on multi-agent deep reinforcement learning(MADRL).In high-dynamic and multi-target aviation communication environments,the rapid changes in channels make it difficult for sensors to accurately capture instantaneous channel state information.This poses a challenge to make centralized jamming decisions with single-agent deep reinforcement learning(DRL)approaches.In response,we design a distributed multi-agent decision architecture(DMADA).We formulate multi-jammer resource allocation as a multiagent Markov decision process(MDP)and propose a fingerprint-based double deep Q-Network(FBDDQN)algorithm for solving it.Each jammer functions as an agent that interacts with the environment in this framework.Through the design of a reasonable reward and training mechanism,our approach enables jammers to achieve distributed cooperation,significantly improving the jamming success rate while considering jamming power cost,and reducing the transmission rate of links.Our experimental results show the FBDDQN algorithm is superior to the baseline methods. 展开更多
关键词 jamming resource allocation JCAPD MADRL wireless communication countermeasure wireless communication networks
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A Base Station Deployment Algorithm for Wireless Positioning Considering Dynamic Obstacles
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作者 Aiguo Li Yunfei Jia 《Computers, Materials & Continua》 2025年第3期4573-4591,共19页
In the context of security systems,adequate signal coverage is paramount for the communication between security personnel and the accurate positioning of personnel.Most studies focus on optimizing base station deploym... In the context of security systems,adequate signal coverage is paramount for the communication between security personnel and the accurate positioning of personnel.Most studies focus on optimizing base station deployment under the assumption of static obstacles,aiming to maximize the perception coverage of wireless RF(Radio Frequency)signals and reduce positioning blind spots.However,in practical security systems,obstacles are subject to change,necessitating the consideration of base station deployment in dynamic environments.Nevertheless,research in this area still needs to be conducted.This paper proposes a Dynamic Indoor Environment Beacon Deployment Algorithm(DIE-BDA)to address this problem.This algorithm considers the dynamic alterations in obstacle locations within the designated area.It determines the requisite number of base stations,the requisite time,and the area’s practical and overall signal coverage rates.The experimental results demonstrate that the algorithm can calculate the deployment strategy in 0.12 s following a change in obstacle positions.Experimental results show that the algorithm in this paper requires 0.12 s to compute the deployment strategy after the positions of obstacles change.With 13 base stations,it achieves an effective coverage rate of 93.5%and an overall coverage rate of 97.75%.The algorithm can rapidly compute a revised deployment strategy in response to changes in obstacle positions within security systems,thereby ensuring the efficacy of signal coverage. 展开更多
关键词 wireless positioning base station deployment dynamic obstacles dynamic obstacle wireless positioning
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Wireless Sensor Network Modeling and Analysis for Attack Detection
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作者 Tamara Zhukabayeva Vasily Desnitsky Assel Abdildayeva 《Computer Modeling in Engineering & Sciences》 2025年第8期2591-2625,共35页
Wireless Sensor Networks(WSN)have gained significant attention over recent years due to their extensive applications in various domains such as environmentalmonitoring,healthcare systems,industrial automation,and smar... Wireless Sensor Networks(WSN)have gained significant attention over recent years due to their extensive applications in various domains such as environmentalmonitoring,healthcare systems,industrial automation,and smart cities.However,such networks are inherently vulnerable to different types of attacks because they operate in open environments with limited resources and constrained communication capabilities.Thepaper addresses challenges related to modeling and analysis of wireless sensor networks and their susceptibility to attacks.Its objective is to create versatile modeling tools capable of detecting attacks against network devices and identifying anomalies caused either by legitimate user errors or malicious activities.A proposed integrated approach for data collection,preprocessing,and analysis in WSN outlines a series of steps applicable throughout both the design phase and operation stage.This ensures effective detection of attacks and anomalies within WSNs.An introduced attackmodel specifies potential types of unauthorized network layer attacks targeting network nodes,transmitted data,and services offered by the WSN.Furthermore,a graph-based analytical framework was designed to detect attacks by evaluating real-time events from network nodes and determining if an attack is underway.Additionally,a simulation model based on sequences of imperative rules defining behaviors of both regular and compromised nodes is presented.Overall,this technique was experimentally verified using a segment of a WSN embedded in a smart city infrastructure,simulating a wormhole attack.Results demonstrate the viability and practical significance of the technique for enhancing future information security measures.Validation tests confirmed high levels of accuracy and efficiency when applied specifically to detecting wormhole attacks targeting routing protocols in WSNs.Precision and recall rates averaged above the benchmark value of 0.95,thus validating the broad applicability of the proposed models across varied scenarios. 展开更多
关键词 wireless sensor network MODELING SECURITY ATTacK DETECTION MONITORING
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Review for wireless communication technology based on digital encoding metasurfaces
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作者 Haojie Zhan Manna Gu +10 位作者 Ying Tian Huizhen Feng Mingmin Zhu Haomiao Zhou Yongxing Jin Ying Tang Chenxia Li Bo Fang Zhi Hong Xufeng Jing Le Wang 《Opto-Electronic Advances》 2025年第7期51-106,共56页
Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present prom... Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present promising applications in wireless communications.This paper reviews the latest advancements in metasurface research within the communication sector,explores metasurface-based wireless relay technologies,and summarizes various wireless communication methods employing different types of metasurfaces across diverse modulation schemes.This paper provides a detailed discussion on the design of wireless communication systems based on coding metasurfaces to simplify transmitter architecture,as well as the development of intelligent coding metasurfaces in the communication field.It also elaborates on the application of vector vortex light fields in metasurface communication.Finally,it offers a forward-looking perspective on wireless communication systems that incorporate coded metasurfaces.This review aims to furnish researchers with a thorough understanding of the current state and future directions of coded metasurface applications in communications. 展开更多
关键词 coding metasurface RIS wireless communications signal modulation TRANSMITTER vortex light
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Demand side management with wireless channel impact in IoT-enabled smart grid system
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作者 Md.Farhad Hossain Kumudu S.Munasinghe +4 位作者 Nishant Jagannath Khandakar Tanvir Ahmed Md.Nabid Hasan Ibrahim Elgendi Abbas Jamalipour 《Digital Communications and Networks》 2025年第2期493-504,共12页
Demand Side Management(DSM)is a vital issue in smart grids,given the time-varying user demand for electricity and power generation cost over a day.On the other hand,wireless communications with ubiquitous connectivity... Demand Side Management(DSM)is a vital issue in smart grids,given the time-varying user demand for electricity and power generation cost over a day.On the other hand,wireless communications with ubiquitous connectivity and low latency have emerged as a suitable option for smart grid.The design of any DSM system using a wireless network must consider the wireless link impairments,which is missing in existing literature.In this paper,we propose a DSM system using a Real-Time Pricing(RTP)mechanism and a wireless Neighborhood Area Network(NAN)with data transfer uncertainty.A Zigbee-based Internet of Things(IoT)model is considered for the communication infrastructure of the NAN.A sample NAN employing XBee and Raspberry Pi modules is also implemented in real-world settings to evaluate its reliability in transferring smart grid data over a wireless link.The proposed DSM system determines the optimal price corresponding to the optimum system welfare based on the two-way wireless communications among users,decision-makers,and energy providers.A novel cost function is adopted to reduce the impact of changes in user numbers on electricity prices.Simulation results indicate that the proposed system benefits users and energy providers.Furthermore,experimental results demonstrate that the success rate of data transfer significantly varies over the implemented wireless NAN,which can substantially impact the performance of the proposed DSM system.Further simulations are then carried out to quantify and analyze the impact of wireless communications on the electricity price,user welfare,and provider welfare. 展开更多
关键词 Smart grid Real time pricing Demand side management wireless communications ZIGBEE
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Reducing the impact of dynamic wireless charging of electric vehicles on the grid through renewable power integration
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作者 K.Qiu H.Ribberink E.Entchev 《DeCarbon》 2025年第1期39-46,共8页
Electrification of roadways using dynamic wireless charging(DWC)technology can provide an effective solution to range anxiety,high battery costs and long charging times of electric vehicles(EVs).With DWC systems insta... Electrification of roadways using dynamic wireless charging(DWC)technology can provide an effective solution to range anxiety,high battery costs and long charging times of electric vehicles(EVs).With DWC systems installed on roadways,they constitute a charging infrastructure or electrified roads(eRoads)that have many advantages.For instance,the large battery size of heavy-duty EVs can significantly be downsized due to charging-whiledriving.However,a high power demand of the DWC system,especially during traffic rush periods,could lead to voltage instability in the grid and undesirable power demand curves.In this paper,a model for the power demand is developed to predict the DWC system's power demand at various levels of EV penetration rate.The DWC power demand profile in the chosen 550 km section of a major highway in Canada is simulated.Solar photovoltaic(PV)panels are integrated with the DWC,and the integrated system is optimized to mitigate the peak power demand on the electrical grid.With solar panels of 55,000 kW rated capacity installed along roadsides in the study region,the peak power demand on the electrical grid is reduced from 167.5 to 136.1 MW or by 18.7%at an EV penetration rate of 30%under monthly average daily solar radiation in July.It is evidenced that solar PV power has effectively smoothed the peak power demand on the grid.Moreover,the locally generated renewable power could help ease off expensive grid upgrades and expansions for the eRoad.Also,the economic feasibility of the solar PV integrated DWC system is assessed using cost analysis metrics. 展开更多
关键词 Power demand Electric vehicles Dynamic wireless charging Renewable energy Solar PV Long-haul trucks
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Computation and wireless resource management in 6G space-integrated-ground access networks
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作者 Ning Hui Qian Sun +2 位作者 Lin Tian Yuanyuan Wang Yiqing Zhou 《Digital Communications and Networks》 2025年第3期768-777,共10页
In 6th Generation Mobile Networks(6G),the Space-Integrated-Ground(SIG)Radio Access Network(RAN)promises seamless coverage and exceptionally high Quality of Service(QoS)for diverse services.However,achieving this neces... In 6th Generation Mobile Networks(6G),the Space-Integrated-Ground(SIG)Radio Access Network(RAN)promises seamless coverage and exceptionally high Quality of Service(QoS)for diverse services.However,achieving this necessitates effective management of computation and wireless resources tailored to the requirements of various services.The heterogeneity of computation resources and interference among shared wireless resources pose significant coordination and management challenges.To solve these problems,this work provides an overview of multi-dimensional resource management in 6G SIG RAN,including computation and wireless resource.Firstly it provides with a review of current investigations on computation and wireless resource management and an analysis of existing deficiencies and challenges.Then focusing on the provided challenges,the work proposes an MEC-based computation resource management scheme and a mixed numerology-based wireless resource management scheme.Furthermore,it outlines promising future technologies,including joint model-driven and data-driven resource management technology,and blockchain-based resource management technology within the 6G SIG network.The work also highlights remaining challenges,such as reducing communication costs associated with unstable ground-to-satellite links and overcoming barriers posed by spectrum isolation.Overall,this comprehensive approach aims to pave the way for efficient and effective resource management in future 6G networks. 展开更多
关键词 Space-integrated-ground Radio access network MEC-based computation resource management Mixed numerology-based wireless resource management
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基于线性化的单级式双有源桥AC-DC变换器最小电流应力控制策略 被引量:1
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作者 王要强 钟正阳 +2 位作者 李想 聂福全 梁军 《电工技术学报》 北大核心 2025年第10期3224-3235,共12页
针对单级式双有源桥AC-DC变换器调制非线性和电流应力较大的问题,该文提出一种基于线性化的变换器最小电流应力控制策略。首先,分析扩展移相(EPS)调制策略的开关特性,对于输入电流与移相比呈非线性的特点,提出一种线性化变频移相控制策... 针对单级式双有源桥AC-DC变换器调制非线性和电流应力较大的问题,该文提出一种基于线性化的变换器最小电流应力控制策略。首先,分析扩展移相(EPS)调制策略的开关特性,对于输入电流与移相比呈非线性的特点,提出一种线性化变频移相控制策略。其次,通过微分极值法实现变换器电流应力的最小化,该控制策略不仅可以降低变换器的控制复杂度,还可以在有效降低变换器电流应力的同时保证开关管具有较宽零电压开通(ZVS)范围,并且移相比和开关频率以解析形式获得,计算简单、易于实现。最后,通过仿真和实验对该文所提控制策略进行验证,证明了该控制策略的可行性。 展开更多
关键词 ac-DC变换器 扩展移相 线性化 最小电流应力 零电压软开关
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单级DAB-DC/AC变换器的效率敏感因子研究
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作者 陈强 杨师骁 +2 位作者 王世龙 王涵宇 马铭遥 《中国电机工程学报》 北大核心 2025年第17期6920-6929,I0026,共11页
单级式双有源桥(dual active bridge,DAB)DC/AC变换器控制自由度多,变压器匝比、漏感、开关频率等参数相互耦合,导致变换器效率优化面临多重制约。该文分析变压器匝比、漏感与软开关范围、漏感电流有效值、漏感电流峰值之间的约束关系,... 单级式双有源桥(dual active bridge,DAB)DC/AC变换器控制自由度多,变压器匝比、漏感、开关频率等参数相互耦合,导致变换器效率优化面临多重制约。该文分析变压器匝比、漏感与软开关范围、漏感电流有效值、漏感电流峰值之间的约束关系,提出直接表征DAB-DC/AC变换器效率的物理量:效率敏感因子。通过研究效率敏感因子对系统损耗的影响机理,实现变换器效率最优的硬件参数设计,为多参数耦合的单级式DAB-DC/AC变换器效率优化提供理论指导。最后通过一台450 W样机验证所提理论的正确性。 展开更多
关键词 双有源桥DC/ac变换器 效率敏感因子 变压器参数 损耗模型 效率优化
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食源性ACE抑制肽的制备方法及作用机制研究进展 被引量:2
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作者 王静 王立霞 +3 位作者 任彩霞 邓雅之 方丹 冯莉萍 《中国食物与营养》 2025年第4期21-28,共8页
目的:综述血管紧张素转化酶(ACE)抑制肽调节高血压的作用机制、食源性ACE抑制肽的制备方法、分离纯化、活性评价、构效关系及分子模拟作用机制,以期为ACE抑制肽的深入研究和进一步开发提供参考。方法:文章采用文献法。结果:从食品原料... 目的:综述血管紧张素转化酶(ACE)抑制肽调节高血压的作用机制、食源性ACE抑制肽的制备方法、分离纯化、活性评价、构效关系及分子模拟作用机制,以期为ACE抑制肽的深入研究和进一步开发提供参考。方法:文章采用文献法。结果:从食品原料中提取制备ACE抑制肽的方法主要包括酶解法、发酵法、模拟消化法、合成法等四大类。目前,ACE抑制肽的分离纯化技术已较为成熟。ACE抑制肽的活性研究主要从体外和体内两个方面进行。ACE抑制肽构效关系的研究主要集中在表面疏水性、分子量大小、分子构象等多个方面。结构-活性关系已被用作分析ACE抑制肽的分子作用机制。结论:食源性ACE抑制肽在体内降血压活性及降血压机制方面的研究还不够系统深入,它的构效关系还需深入研究。ACE抑制肽分离纯化过程需要进一步改进,同时还需加强食源性ACE抑制肽安全性研究、生产过程中的质量管理,保障消费者的安全与健康。 展开更多
关键词 acE抑制肽 制备方法 活性评价 构效关系 分子机制
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呕吐毒素对人心肌细胞AC16增殖和凋亡的影响
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作者 张百刚 李阳 +1 位作者 焦禄 付炳刚 《现代食品科技》 北大核心 2025年第4期109-116,共8页
该研究旨在探讨呕吐毒素对人心肌细胞AC16增殖和凋亡的影响。不同浓度的呕吐毒素处理人心肌细胞AC16后,采用CCK-8法检测细胞增殖抑制率,荧光显微镜观察细胞形态学变化,通过乳酸脱氢酶释放检测细胞毒性,Annexin V-FITC流式细胞法检测凋... 该研究旨在探讨呕吐毒素对人心肌细胞AC16增殖和凋亡的影响。不同浓度的呕吐毒素处理人心肌细胞AC16后,采用CCK-8法检测细胞增殖抑制率,荧光显微镜观察细胞形态学变化,通过乳酸脱氢酶释放检测细胞毒性,Annexin V-FITC流式细胞法检测凋亡率的变化,JC-1荧光探针法检测线粒体膜电位的变化。Western blotting测定Bax和Bcl-2凋亡相关蛋白的表达水平。结果表明,呕吐毒素显著抑制AC16细胞增殖并诱导凋亡,呈现明显的剂量效应关系。2、4、8μmol/L的呕吐毒素处理24 h后,细胞凋亡率分别为14.89%、43.20%和51.40%。线粒体膜电位表达水平的变化暗示吐毒素可能通过线粒体途径引起AC16细胞凋亡。Western blotting结果表明,呕吐毒素上调了Bax蛋白表达,下调了Bcl-2蛋白表达。综上所述,呕吐毒素对AC16细胞有毒性效应,具有明显的抑制增殖效果,并促使细胞发生凋亡,线粒体膜电位的变化显示呕吐毒素可能是通过线粒体途径诱导了人心肌细胞AC16的凋亡。该研究为进一步研究呕吐毒素对心肌和细胞的损伤机制提供了理论支持。 展开更多
关键词 呕吐毒素 ac16细胞 凋亡 增殖
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基于CCTA定量分析ACS与SCAD冠状动脉斑块成分及负荷特征
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作者 史志伟 《中国CT和MRI杂志》 2025年第6期80-82,共3页
目的基于冠状动脉CT血管成像(CCTA)定量分析急性冠脉综合征(ACS)与稳定性冠心病(SCAD)冠状动脉斑块成分及负荷特征。方法回顾性收集2020年12月至2023年12月期间我院收治的冠心病患者118例,根据其具体病理改变将其分为ACS组(n=56)与SCAD... 目的基于冠状动脉CT血管成像(CCTA)定量分析急性冠脉综合征(ACS)与稳定性冠心病(SCAD)冠状动脉斑块成分及负荷特征。方法回顾性收集2020年12月至2023年12月期间我院收治的冠心病患者118例,根据其具体病理改变将其分为ACS组(n=56)与SCAD组(n=62)。收集两组患者性别、年龄、BMI等一般资料以及CCTA等检查资料,比较两组冠状动脉斑块成分及负荷。结果两组患者斑块总体积(TPV)、钙化成分体积(CPV)、钙化成分负荷(CPB)、纤维成分体积(FPV)、纤维成分负荷(FPB)、脂质成分体积(LPV)差异无统计学意义(P>0.05);ACS组总斑块负荷(TPB)、脂质成分负荷(LPB)高于SCAD组(P<0.05);ACS组CT易损特征中点状钙化、正向重构以及低密度斑块的比例均较SCAD组高,且CT高危斑块比例也相对更高(P<0.05)。结论基于CCTA定量分析ACS与SCAD冠状动脉斑块成分及负荷特征发现,ACS患者不稳定斑块及高危斑块发生风险更高。 展开更多
关键词 CCTA acS SCAD 冠状动脉 板块成分 板块负荷
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过表达ace-miR-14-y对中华蜜蜂工蜂幼虫靶基因表达及个体和肠道重量的影响
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作者 徐国钧 刘小玉 +7 位作者 刘治滩 任亚萍 康婧 宓诗雨 胡艳雯 刘彩珍 陈大福 郭睿 《应用昆虫学报》 北大核心 2025年第1期114-122,共9页
【目的】探究过表达ace-miR-14-y对中华蜜蜂Apis cerana cerana工蜂幼虫靶基因表达及个体和肠道重量的影响,进而揭示ace-miR-14-y的潜在调控作用。【方法】使用茎环RT-PCR和Sanger测序验证ace-miR-14-y的表达和序列。采用相关软件预测... 【目的】探究过表达ace-miR-14-y对中华蜜蜂Apis cerana cerana工蜂幼虫靶基因表达及个体和肠道重量的影响,进而揭示ace-miR-14-y的潜在调控作用。【方法】使用茎环RT-PCR和Sanger测序验证ace-miR-14-y的表达和序列。采用相关软件预测和分析ace-miR-14-y的靶基因。通过饲喂模拟物(Mimic)进行幼虫肠道中ace-miR-14-y的过表达。利用RT-qPCR检测ace-miR-14-y的过表达效果及过表达ace-miR-14-y后靶基因的相对表达量。使用电子天平对幼虫个体和肠道进行称重。【结果】ace-miR-14-y在工蜂幼虫肠道中存在和表达;ace-miR-14-y共靶向265个基因,涉及33个GO条目与180条KEGG通路;mimic-miR-14组ace-miR-14-y的表达量显著高于mimic-NC组(P<0.05);过表达ace-miR-14-y后,靶基因Wg和AP-1的表达量均显著下调(P<0.05),幼虫个体和肠道的重量均极显著上升(P<0.01)。【结论】过表达ace-miR-14-y显著影响中华蜜蜂工蜂幼虫肠道中靶基因Wg和AP-1的表达及幼虫个体和肠道的重量,ace-miR-14-y通过调节Wg和AP-1表达发挥潜在的调控作用。 展开更多
关键词 中华蜜蜂 幼虫 ace-miR-14-y 过表达 靶基因
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淡豆豉抑制ACE作用及其活性成分初步研究
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作者 李刚 马书伟 +5 位作者 王立元 谢卫华 胡叔慧 肖威 汪玉军 谢小梅 《时珍国医国药》 北大核心 2025年第14期2630-2635,共6页
目的研究淡豆豉对血管紧张素转化酶(ACE)的抑制作用及其活性成分。方法按实验室前期建立的工艺获取淡豆豉炮制过程中不同时间点的样本;采用高效液相色谱法(HPLC)和超高效液相色谱-串联质谱法(UPLC-MS/MS)法测定各样本中大豆苷元、染料... 目的研究淡豆豉对血管紧张素转化酶(ACE)的抑制作用及其活性成分。方法按实验室前期建立的工艺获取淡豆豉炮制过程中不同时间点的样本;采用高效液相色谱法(HPLC)和超高效液相色谱-串联质谱法(UPLC-MS/MS)法测定各样本中大豆苷元、染料木素和γ-氨基丁酸(GABA)含量;采用Cushman测定法加以改进,以马脲酰-组氨酰-亮氨酸(HHL)为底物,紫外分光光度计测定吸光度,计算各样本的ACE抑制率;SPSS统计软件对淡豆豉炮制中各时间点样本的大豆苷元、染料木素、GABA含量与ACE抑制率进行相关性分析。结果大豆苷元、染料木素在再闷12d时达最高分别为(0.951±0.296)mg/g、(0.920±0.170)mg/g,GABA在再闷15d时达最高为(7.03±1.29)mg/g。不同时间点样本的醇提物对ACE抑制率低且无明显变化(r<0,P>0.05),“再闷”后样品的水提物对ACE抑制作用明显,最高达90.62%,且GABA含量与ACE抑制率呈正相关(r>0.99,P<0.05)。结论淡豆豉具有较强的体外ACE抑制作用,GABA可能是其主要活性成分。 展开更多
关键词 淡豆豉 大豆苷元 染料木素 Γ-氨基丁酸 血管紧张素转化酶
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一种新型交流侧调频输出的AC-DC双向变换器研究
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作者 刘晓东 张君扬 +2 位作者 李宁 刘宿城 孙海涛 《电源学报》 北大核心 2025年第4期111-119,共9页
针对传统多级式AC-DC双向变换器功率密度较低、应用场景单一的问题,提出1种新型交流可调频输出AC-DC双向变换器。采用矩阵式变频电路代替全桥电路,结合整流与逆变2种工作模式控制方法,实现变换器无需直流环节的单级式交-交变频功能,使... 针对传统多级式AC-DC双向变换器功率密度较低、应用场景单一的问题,提出1种新型交流可调频输出AC-DC双向变换器。采用矩阵式变频电路代替全桥电路,结合整流与逆变2种工作模式控制方法,实现变换器无需直流环节的单级式交-交变频功能,使得变换器在满足车网互动V2G(vehicle-to-grid)能源交互策略的基础上新增新能源电动车的能量灵活外放功能。控制层面,当变换器工作在逆变模式时,采用比例谐振控制以获得较低的总谐波失真及频率可调特性,进而覆盖更多交流侧用电器需求;当变换器工作在整流模式时,基于连续导通模式CCM(continuous conduction mode)的平均电流控制可保证交流侧高功率因数值与直流侧稳压输出。最后,搭建MATLAB/Simulink仿真模型与硬件实验平台进行验证,结果证明了所提拓扑的正确性及有效性。 展开更多
关键词 ac-DC双向变换器 比例谐振控制 车网互动 频率可调
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3.0T核磁共振成像及血清黏蛋白5AC、异常糖链糖蛋白单独及联合检测对胰腺癌的诊断价值
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作者 杨惠娅 沈丽萍 陈建新 《癌症进展》 2025年第2期167-170,共4页
目的探讨3.0T核磁共振成像(NMRI)及血清黏蛋白5AC(MUC5AC)、异常糖链糖蛋白(TAP)单独及联合检测对胰腺癌的诊断价值。方法选取87例疑似胰腺癌患者,接受NMRI检查及血清MUC5AC、TAP水平检测。以病理检查结果为金标准,评估3.0T NMRI及血清M... 目的探讨3.0T核磁共振成像(NMRI)及血清黏蛋白5AC(MUC5AC)、异常糖链糖蛋白(TAP)单独及联合检测对胰腺癌的诊断价值。方法选取87例疑似胰腺癌患者,接受NMRI检查及血清MUC5AC、TAP水平检测。以病理检查结果为金标准,评估3.0T NMRI及血清MUC5AC、TAP单独及联合检测对胰腺癌的诊断价值。结果病理检查结果显示,87例疑似胰腺癌患者中,胰腺癌37例,胰腺炎50例。NMRI及血清MUC5AC、TAP联合检测诊断胰腺癌的灵敏度为94.59%,特异度为90.00%,准确度为91.95%,阳性预测值为87.50%,阴性预测值为95.74%,均高于各指标单独检测。结论3.0T NMRI及血清MUC5AC、TAP联合检测诊断胰腺癌的价值较高,或可提高临床胰腺癌的早期检出率。 展开更多
关键词 胰腺癌 核磁共振成像 黏蛋白5ac 异常糖链糖蛋白 诊断
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单级式双有源桥型AC-DC变换器电压增益分析及优化调制策略
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作者 王要强 闫武庆 +2 位作者 聂福全 刘文君 梁军 《电力自动化设备》 北大核心 2025年第9期103-109,118,共8页
为了解决单级式双有源桥型AC-DC变换器在宽电压范围内软开关范围受限和漏感电流峰值较大的问题,提出一种计及电压增益的扩展移相变频调制策略。分析了副边侧扩展移相调制在宽电压范围内存在的漏感电流峰值较大的问题,继而提出一种计及... 为了解决单级式双有源桥型AC-DC变换器在宽电压范围内软开关范围受限和漏感电流峰值较大的问题,提出一种计及电压增益的扩展移相变频调制策略。分析了副边侧扩展移相调制在宽电压范围内存在的漏感电流峰值较大的问题,继而提出一种计及电压增益的双模式调制;在此基础上,分析升压与降压模式的软开关条件,通过约束特定开关管开通时刻的漏感电流值,推导得出移相比和开关频率的数学表达式。该调制策略可以实现全范围软开关,并且能在一定程度上减小漏感电流峰值。通过仿真和实验证明了所提调制策略的可行性。 展开更多
关键词 单级式ac-DC变换器 双有源桥变换器 宽电压增益 扩展移相 软开关
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隔离型AC/DC矩阵变换器控制策略的研究
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作者 王晓雷 康珂琦 +1 位作者 郭飞亚 常世喆 《自动化应用》 2025年第18期192-197,共6页
隔离型AC/DC矩阵变换器(IAMC)凭借功率双向传输、电气隔离、高控制自由度及功率密度等优势,在储能系统中展现出重要的应用价值。系统分析了该变换器的电路拓扑结构、工作原理及调控策略,创新性地提出了一种改进的控制策略,通过构建外移... 隔离型AC/DC矩阵变换器(IAMC)凭借功率双向传输、电气隔离、高控制自由度及功率密度等优势,在储能系统中展现出重要的应用价值。系统分析了该变换器的电路拓扑结构、工作原理及调控策略,创新性地提出了一种改进的控制策略,通过构建外移相角预测模型,显著提升动态响应性能,同时采用多目标优化分组机制来有效降低MPC计算复杂度。通过基于MATLAB/Simulink的仿真平台构建对比实验,结果表明,模型预测控制策略在动态响应速度、抗扰动能力等核心指标上,较传统网侧电流闭环PI控制表现出显著优势。 展开更多
关键词 隔离型ac/DC矩阵式变换器 动态响应 模型预测控制 外移相角
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Ultraconformable Integrated Wireless Charging Micro-Supercapacitor Skin 被引量:2
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作者 Chang Gao Qing You +5 位作者 Jiancheng Huang Jingye Sun Xuan Yao Mingqiang Zhu Yang Zhao Tao Deng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期46-58,共13页
Conformable and wire-less charging energy storage devices play important roles in enabling the fast development of wearable,non-contact soft electronics.However,current wire-less charging power sources are still restr... Conformable and wire-less charging energy storage devices play important roles in enabling the fast development of wearable,non-contact soft electronics.However,current wire-less charging power sources are still restricted by limited flexural angles and fragile connection of components,resulting in the failure expression of performance and constraining their fur-ther applications in health monitoring wearables and moveable artificial limbs.Herein,we present an ultracompatible skin-like integrated wireless charging micro-supercapacitor,which building blocks(including electrolyte,electrode and substrate)are all evaporated by liquid precursor.Owing to the infiltration and permeation of the liquid,each part of the integrated device attached firmly with each other,forming a compact and all-in-one configuration.In addition,benefitting from the controllable volume of electrode solution precursor,the electrode thickness is easily regulated varying from 11.7 to 112.5μm.This prepared thin IWC-MSC skin can fit well with curving human body,and could be wireless charged to store electricity into high capacitive micro-supercapacitors(11.39 F cm-3)of the integrated device.We believe this work will shed light on the construction of skin-attachable electronics and irregular sensing microrobots. 展开更多
关键词 Micro-supercapacitor Electronic skin Supercapacitor skin wireless charging energy storage device
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