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Ethical concerns in aging research: perspectives of global frontline researchers

Science China Life Sciences 2024年第10期67卷 2149-2156页

作者： Yaojin Peng Lulu Ding zhenyu xiao Moshi Song Jianwei Lv Guang-Hui Liu Key Laboratory of Organ Regeneration and Reconstruction State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of Sciences University of Chinese Academy of Sciences Beijing Institute for Stem Cell and Regenerative Medicine Institute for Stem Cell and Regeneration Chinese Academy of Sciences Aging Biomarker Consortium (ABC) School of Life Science Beijing Institute of Technology School of Life Sciences Xiamen University Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical University Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical University

This study investigated the ethical landscape of aging research amid the increasing global focus on extending the human lifespan and health span. Our global survey of 180 researchers across 38 jurisdictions revealed divergent perceptions of aging, a consensus regarding the feasibility of delaying aging, and multiple perspectives regarding lifespan extension. The present findings underscore a paradigm shift toward inclusive and ethically sound research, emphasizing the need for an approach that strikes a balance between basic and clinical research. In addition, this study highlighted key ethical concerns in aging research, including the effects of misleading advertising, potential inequality in access to aging interventions, and risks pertaining to the extrapolation of research findings from lower-model organisms to humans. The insights presented in this paper call for an integrated approach for overcoming the complex ethical and societal challenges in aging research to ensure responsible and equitable advancements in this burgeoning field.

关键词： aging ethical landscape ethics surveys and questionnaires

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Service Function Chain Migration in LEO Satellite Networks

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China Communications 2024年第3期21卷 247-259页

作者： Geng Yuhui Wang Niwei Chen Xi Xu xiaofan Zhou Changsheng Yang Junyi xiao zhenyu Cao Xianbin School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Key Laboratory of Advanced Technology of Near Space Information System Ministry of Industry and Information Technology of ChinaBeijing 100191China Shanghai Key Laboratory of Satellite Network Shanghai 201204China Shanghai Satellite Network Research Institute Co. Ltd.Shanghai 201204China

With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)satellite *** due to the scarcity of bandwidth resources and dynamic topology of LEO satellites,the static SFC placement schemes may cause performance degradation,resource waste and even service *** this paper,we consider migration and establish an online migration model,especially considering the dynamic *** the scarcity of bandwidth resources,the model aims to maximize the total number of accepted SFCs while incurring as little bandwidth cost of SFC transmission and migration as *** to its NP-hardness,we propose a heuristic minimized dynamic SFC migration(MDSM)algorithm that only triggers the migration procedure when new SFCs are *** results demonstrate that MDSM achieves a performance close to the upper bound with lower complexity.

关键词： network function virtualization(NFV) resource allocation satellite networks service function chain(SFC) SFC migration SFC placement soft-ware defined network(SDN)

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Space/Air Covert Communications:Potentials,Scenarios,and Key Technologies

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China Communications 2024年第3期21卷 1-18页

作者： Mao Haobin Liu Yanming Zhu Lipeng Mao Tianqi xiao zhenyu Zhang Rui Han Zhu Xia Xianggen School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore School of Science and Engineering Shenzhen Research Institute of Big Datathe Chinese University of Hong KongShenzhenGuangdong 518172China Department of Electrical and Computer Engineering University of HoustonHoustonTX 77004USA Department of Computer Science and Engineering Kyung Hee UniversitySeoulSouth Korea446-701 Department of Electrical and Computer Engineering University of DelawareNewarkDE 19716USA

Space/air communications have been envisioned as an essential part of the next-generation mobile communication networks for providing highquality global connectivity. However, the inherent broadcasting nature of wireless propagation environment and the broad coverage pose severe threats to the protection of private data. Emerging covert communications provides a promising solution to achieve robust communication security. Aiming at facilitating the practical implementation of covert communications in space/air networks, we present a tutorial overview of its potentials, scenarios, and key technologies. Specifically, first, the commonly used covertness constraint model, covert performance metrics, and potential application scenarios are briefly introduced. Then, several efficient methods that introduce uncertainty into the covert system are thoroughly summarized, followed by several critical enabling technologies, including joint resource allocation and deployment/trajectory design, multi-antenna and beamforming techniques, reconfigurable intelligent surface(RIS), and artificial intelligence algorithms. Finally, we highlight some open issues for future investigation.

关键词： artificial intelligence(AI) sixth generation(6G) space-air-ground integrated networks(SAGINs) space/air covert communications

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Hierarchical Fe_(x)Bi_(2−x)S_(3) solid solutions for boosted supercapacitor performance

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Nano Research 2024年第5期17卷 3997-4005页

作者： Fengming Zhou xiaodong Wang Ruijie Jing xiaoyu Li Qi Zhang Zhenjiang Li Yunmei Du zhenyu xiao Lei Wang International Cooperation United Laboratory of Eco-chemical Engineering and Green Manufacturing College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Technology Innovation Center of Battery Safety and Energy Storage Technology QingdaoInternational Science and Technology Cooperation Base of QingdaoCollege of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042China

For the pursuit of high energy supercapacitors,the development of high performance pseudocapacitance or battery-type negative electrode material is urgently needed to make up for the capacity shortage of commercial electric double layer capacitor(EDLC)type ***,a porous and defect-rich Fe_(x)Bi_(2-x)S_(3) solid solution structure is firstly constructed by employing Fe-doped Bi_(2)O_(2)CO_(3) porous nanosheets as a precursor,which presents dramatically increased energy storage performance than Bi_(2)S_(3) and FeS_(2) *** the optimized Fe_(x)Bi_(2-x)S_(3) solid solution(FeBiS-60%),the Fe solute is free and random dispersed in Bi_(2)S_(3) framework,which can effectively modulate the electronic structure of Bi element and introduce rich-defect due to the existence of Fe(II).Meanwhile,the FeBiS-60%,constructed by pore nanosheets that are assembled by self-supported basic nanorod units,presents rich mesoporous channels for fast mass transfer and abundant active sites for promoting capacity ***,a high capacitance of 832.8 F·g^(-1) at a current density of 1 A·g^(-1) is achieved by the FeBiS-60%***,a fabricated Ni3S_(2)@Co_(3)S_(4)(NCS)//FeBiS-60%hybrid supercapacitor device delivers an outstanding energy density of 85.33 Wh·kg^(-1) at the power density of 0.799 kW·kg^(-1),and ultra-long lifespan of remaining 86.7%initial capacitance after 8700 cycles.

关键词： supercapacitor solid solutions defect structure hierarchical structure Bi_(2)S_(3)

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Recent advances in design of hydrogen evolution reaction electrocatalysts at high current density:A review

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Chinese Journal of Catalysis 2024年第8期63卷 33-60页

作者： Zhipeng Li xiaobin Liu Qingping Yu Xinyue Qu Jun Wan zhenyu xiao Jingqi Chi Lei Wang Key Laboratory of Eco-chemical Engineering International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufac-turingCollege of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongChina College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina

The electrolysis of water powered by renewable energy sources offers a promising method of"green hydrogen"production,which is considered to be at the heart of future carbon-neutral energy *** the past decades,researchers have reported a number of hydrogen evolution reaction(HER)electrocatalysts with activity comparable to that of commercial Pt/C,but most of them are tested within a small current density range,typically no more than 500 mA cm^(-2).To realize the industrial application of hydrogen production from water electrolysis,it is essential to develop high-efficiency HER electrocatalysts at high current density(HCD≥500 mA cm^(-2)).Nevertheless,it remains challenging and significant to rational design HCD electrocatalysts for *** this paper,the design strategy of HCD electrocatalysts is discussed,and some HCD electrocatalysts for HER are reviewed in seven categories(alloy,metal oxide,metal hydroxide,metal sulfide/selenide,metal nitride,metal phosphide and other derived electrocatalysts).At the end of this article,we also pro-pose some viewpoints and prospects for the future development and research directions of HCD electrocatalysts for HER.

关键词： Electrocatalyst High current density Hydrogen evolution reaction Water electrolysis

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价值链视角下中国制造业出口隐含的职业收入结构变化研究

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国际贸易问题 2024年第8期 36-54页

作者：祝坤福王家荣肖振宇中国人民大学经济学院中国人民大学商学院

本文在全球价值链生产分解框架下利用经济合作与发展组织(OECD)的国际投入产出数据库,测算了2000—2018年中国制造业出口中隐含的不同职业收入,不仅从收入结构视角剖析了中国制造业发展的生产化和服务化演变历程,而且对出口所隐含职业... 详细信息

本文在全球价值链生产分解框架下利用经济合作与发展组织(OECD)的国际投入产出数据库,测算了2000—2018年中国制造业出口中隐含的不同职业收入,不仅从收入结构视角剖析了中国制造业发展的生产化和服务化演变历程,而且对出口所隐含职业收入结构变化的驱动因素进行了深入探究。研究结果表明:从全球一般规律来看,一国人均收入越高,其制造业出口中所隐含的生产性职业收入占比越低,服务性职业收入占比越高;从不同价值链活动来看,价值链分工越为复杂的生产活动,其服务性职业收入占比越高,生产性职业收入占比越低;从各类价值链活动内部来看,研发强度越高的制造业,服务性职业收入占比越高;结构分解分析(SDA)结果显示,在生产化阶段,制造业出口中生产性职业收入占比的上升主要是由行业内变化所致,而行业间劳动收入结构变化在其间发挥了抑制作用;在服务化阶段,行业内职业收入占比变化和行业间劳动收入结构变化共同推动了制造业出口服务性职业收入比重的上升。根据研究结论,本文对中国从“制造大国”迈向“制造强国”的可行路径提出了相关建议。

关键词：制造业服务化职业收入全球价值链功能化分工

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12000年以来天文季节长度变化序列的重建及其特征分析

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地球物理学进展 2024年第2期39卷 447-459页

作者：肖振宇梁中王建邬愉婷孙威南京师范大学地理科学学院南京210023 江苏第二师范学院城市与资源环境学院南京211200 上海工程技术大学数理与统计学院上海201620

已有研究发现季节长度变化与气候冷暖变化密切相关,但是到目前为止还没有一个长度超过1万年的准确度很高的季节长度变化序列.该文利用星历数据DE441重建了12000年以来季节长度的时间变化序列,并利用ICEEMDAN与连续小波变换两种方法提取... 详细信息

已有研究发现季节长度变化与气候冷暖变化密切相关,但是到目前为止还没有一个长度超过1万年的准确度很高的季节长度变化序列.该文利用星历数据DE441重建了12000年以来季节长度的时间变化序列,并利用ICEEMDAN与连续小波变换两种方法提取了夏季与冬季长度不同尺度的周期性信号,揭示了它们在过去12000年以来不同时间段内的变化特征.研究发现:北半球夏季时长变化存在2.5年、4年、5.5年、11.8年、15.8年、29年、84年、101年、223年、约500年和约850年的周期,北半球冬季时长变化具有2.5年、4年、5.5年、11.8年、15.8年、29年、74年、167年、约500年和约1000年的周期.其中11.8年的短尺度周期变化贯穿于整个过去12000年;2.5年、4年、5.5年与15.8年左右的周期则是在全新世某个时间段内变化较为显著.该研究结果为进一步深入理解和探讨气候变化的原因和机制提供了新的数据和依据.

关键词：季节长度序列重建周期分析气候变化

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Network Element Placement for Space-Air-Ground Integrated Network:A Tutorial

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Chinese Journal of Electronics 2022年第6期31卷 1013-1024页

作者： GENG Yuhui CAO Xianbin CUI Huanxi xiao zhenyu School of Electronic and Information Engineering Beihang University

With the demand for Internet connectivity in remote areas, the space-air-ground integrated network(SAGIN) was proposed to achieve ubiquitous coverage and enhance service capabilities of extant terrestrial networks. The paradigm of virtual network element placement(NEP) is applied into SAGIN. It can save energy and operating costs by placing specific network elements(NEs) as software instances. In addition, it helps to provide services in end-to-end networks with its ability to allocate and manage resources flexibly. However, NEP faces some challenges in SAGIN. The network topologies can be dynamic, and links such as the satellite-to-ground and air-to-ground ones are prone to fail. These will make NEP management more complicated. Moreover, the static NEP schemes are hard to accommodate the time-varying traffic. In this context, this work explains the NEP problem in SAGIN from three aspects, i.e., the SAGIN radio access network(RAN), the SAGIN core network(CN), and the SAGIN barrier network(BN). First, the physical and networking architectures of SAGIN are introduced. Then the status of the network element placement and corresponding challenges are described from these two aspects. Finally, this paper discusses future research directions and key technical challenges.

关键词： Network element placement Space-airground integrated network (SAGIN) Software defined network (SDN) Network function virtualization (NFV) Network architectures Resource allocation

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UAV Communications with Millimeter-Wave Beamforming:Potentials,Scenarios,and Challenges

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China Communications 2020年第9期17卷 147-166页

作者： zhenyu xiao Lipeng Zhu Xiang-Gen Xia School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Department of Electrical and Computer Engineering University of DelawareNewarkDE 19716USA

Unmanned aerial vehicle(UAV)has been widely used in many fields and is arousing global *** the resolution of the equipped sensors in the UAV becomes higher and the tasks become more complicated,much higher data rate and longer communication range are required in the foreseeable *** the millimeter-wave(mm Wave)band can provide more abundant frequency resources than the microwave band,much higher achievable rate can be guaranteed to support UAV services such as video surveillance,hotspot coverage,and emergency communications,*** flexible mm Wave beamforming can be used to overcome the high path loss caused by the long propagation *** this paper,we study three typical application scenarios for mm Wave-UAV communications,namely communication terminal,access point,and backbone *** present several key enabling techniques for UAV communications,including beam tracking,multi-beam forming,joint Tx/Rx beam alignment,and full-duplex relay *** show the coupling relation between mm Wave beamforming and UAV positioning for mm Wave-UAV ***,we summarize the challenges and research directions of mm Wave-UAV communications in detail.

关键词： unmanned aerial vehicle(UAV) millimeter-wave(mmWave)communications beamforming beam tracking deployment

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面向6G的星地融合网络频谱共享技术

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中兴通讯技术 2024年第4期30卷 50-56页

作者：瞿重希毛浩斌许憧张远钧肖振宇北京航空航天大学中国北京100191

卫星网络被公认为是下一代移动通信系统的重要组成部分,其与现有的地面蜂窝网络实现优势互补形成星地融合网络,可以为全球范围内的海量用户提供无处不在的宽带接入服务。而两网如何高效共享有限的频谱资源、缓解同频共存干扰成为当前的... 详细信息

卫星网络被公认为是下一代移动通信系统的重要组成部分,其与现有的地面蜂窝网络实现优势互补形成星地融合网络,可以为全球范围内的海量用户提供无处不在的宽带接入服务。而两网如何高效共享有限的频谱资源、缓解同频共存干扰成为当前的技术难点与热点问题之一。分析了星地融合网络频谱共享时存在的典型干扰类型,并对星地频谱共享场景中系统间干扰进行了仿真。介绍了星地频谱共享需要进一步研究的关键技术,并总结了星地融合网络频谱共享面临的挑战。

关键词： 6G 星地融合网络频谱共享同频干扰

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