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Black holes as the source of dark energy:A stringent test with high-redshift JWST AGNs

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 181-188页

作者： Lei Lei Lei Zu Guan-Wen yuan Zhao-Qiang Shen Yi-Ying wang yuan-zhu wang Zhen-Bo Su Wen-Ke Ren Shao-Peng Tang Hao Zhou Chi Zhang Zhi-Ping Jin Lei Feng Yi-Zhong Fan Da-Ming Wei Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black holes(BHs)with an index of k≈3;hence,BHs serve as the astrophysical source of dark ***,the data sample is limited for the redshifts of≤*** recent years,the James Webb Space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z~***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black holes with k=3 at a confidence level of~2σ,which challenges the hypothesis that BHs serve as the origin of dark *** work on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark energy supermassive black hole active galactic nuclei James Webb Space Telescope

Improving coarse frame synchronization by UE-UE interference for OFDMA-TDD systems

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 30-34页

作者： zhu yuan wang Chun-ye YANG Da-cheng Wireless Theory and Technology Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies the coarse flame synchronization of orthogonal frequency division multiplexing access-time division duplex （OFDMA-TDD） systems and proposes a new method to improve coarse frame synchronization performance. The new method utilizes the user equipment to user equipment （UE-UE） interference, which is usually considered as a specific challenge for time division duplex （TDD） and also as implicit frame boundary information to enhance coarse frame synchronization performance. Numerical results show the synchronization performance is imoroved bv the new method.

关键词： orthogonal frequency division multiplexing access time division duplex synchronization training symbol

Biotribological behavior of ultra high molecular weight polyethylene composites containing bovine bone hydroxyapatite

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Journal of China University of Mining and Technology 2008年第4期18卷 606-612页

作者： LIU Jin-long zhu yuan-yuan wang Qing-liang GE Shi-rong School of Materials and Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Wear particles of ultrahigh molecular weight polyethylene （UHMWPE） are the main cause of long-term failure of total joint replacements. Therefore, increasing its wear resistance or bioactivity will be very useful in order to obtain high quality artificial joints. In our study, UHMWPE composites filled with the bovine bone hydroxyapatite （BHA） were prepared by the method of compression moulding. A ball-on-disc wear test was carried out with a Universal Micro-Tribometer to investigate the friction and wear behavior of a Si3N4 ceramic ball, cross-sliding against the UHMWPE/BHA composites with human plasma lubrication. At the same time, the profiles of the worn grooves on the UHMWPE/BHA surface were scanned. The experimental results indicate that the addition of BHA to UHMWPE had a significant effect on the biotribological behavior of UHMWPE cross-sliding against the Si3N4 ceramic ball. The addition of BHA powder enhanced the hardness and modulus of elasticity of these composites and decreased the friction coefficients and wear rates under conditions of human plasma lubrication. When the added amount of BHA powders was up to 20%-30%, UHMWPE/BHA composites demonstrated the designed performance of the mechanical properties and biotribological behavior.

关键词： UHMWPE hydroxyapatite biotribology composite material

Growth process,defects,and dopants of bulkβ-Ga_(2)O_(3)semiconductor single crystals

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China Foundry 2024年第5期21卷 491-506页

作者： Yan-shen wang Ming-zhi zhu yuan Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Beijing 100084China

β-gallium oxide(β-Ga2O3),as the typical representative of the fourth generation of semiconductors,has attracted increasing attention owing to its ultra-wide bandgap,superior optical properties,and excellent tolerance to high temperature and *** to the single crystals of other semiconductors,high-quality and large-sizeβ-Ga_(2)O_(3)single crystals can be grown with low-cost melting methods,making them highly *** this review,the growth process,defects,and dopants ofβ-Ga_(2)O_(3)are primarily ***,the growth process(e.g.,decomposition,crucible corrosion,spiral growth,and development)ofβ-Ga_(2)O_(3)single crystals are summarized and compared in ***,the defects ofβ-Ga_(2)O_(3)single crystals and the influence of defects on Schottky barrier diode(SBD)devices are emphatically ***,the influences of impurities and intrinsic defects on the electronic and optical properties ofβ-Ga_(2)O_(3)are also briefly *** this comprehensive analysis,the article offers a concise summary of the current state,challenges and prospects ofβ-Ga_(2)O_(3)single crystals.

关键词： β-Ga_(2)O_(3) single-crystal growth defects dopants semiconductor

On the Difference Between the Skew-rank of an Oriented Graph and the Rank of Its Underlying Graph

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 129-136页

作者： Jia-min zhu Bo-jun yuan Yi wang School of Mathematical Sciences Anhui UniversityHefei230601China School of Science Zhejiang University of Science and TechnologyHangzhou310023China

Let G be a simple graph and G~σ be the oriented graph with G as its underlying graph and orientation σ.The rank of the adjacency matrix of G is called the rank of G and is denoted by r(G).The rank of the skew-adjacency matrix of G~σ is called the skew-rank of G~σ and is denoted by sr(G~σ).Let V(G)be the vertex set and E(G) be the edge set of *** cyclomatic number of G,denoted by c(G),is equal to |E(G)|-|V(G)|+ω(G),where ω(G) is the number of the components of *** is proved for any oriented graph G~σ that-2c(G)≤sr(G~σ)-r(G)≤2c(G).In this paper,we prove that there is no oriented graph G~σwith sr(G~σ)-r(G)=2c(G)-1,and in addition,there are infinitely many oriented graphs G~σ with connected underlying graphs such that c(G)=k and sr(G~σ)-r(G)=2c(G)-l for every integers k,l satisfying 0 ≤l≤4k and l≠1.

关键词： cyclomatic number rank skew-rank

Long-term changes in radial growth of seven tree species in the mixed broadleaf-Korean pine forest in Northeast China:Are deciduous trees favored by climate change?

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Journal of Forestry Research 2024年第5期35卷 63-77页

作者： Xiufang Gong Danyang yuan Liangjun zhu Zongshan Li Xiaochun wang National Engineering Laboratory for Applied Technology of Forestry and Ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004People’s Republic of China Center for Ecological Research and Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085People’s Republic of China

The role of the temperate mixed broadleaf-Korean pine forest(BKF)in global biogeochemical cycles will depend on how the tree species community responds to climate;however,species-specific responses and vulner-abilities of common trees in BKF to extreme climates are poorly *** we used dendrochronological meth-ods to assess radial growth of seven main tree species(Pinus koraiensis,Picea jezoensis,Abies nephrolepis,Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Ulmus davidiana)in an old-growth BKF in response to climate changes in the Xiaoxing’an Mountains and to improve predictions of changes in the tree species *** in most months and winter precipita-tion significantly negatively affected growth of *** and ***,but positively impacted growth of *** and the broadleaf species,especially ***-rica and *** and relative humidity in June significantly positively impacted the growth of most tree *** positive effect of the temperature during the previous non-growing season(PNG)on growth of *** and *** strengthened significantly with rapid warming around 1981,while the impact of PNG temperature on the growth of *** and *** changed from significantly negative to weakly negative or positive at this *** negative response of radial growth of *** and *** to precipitation during the growing season gradually weakened,and the negative response to PNG precipitation was *** the studied species,*** was the most resistant to drought,and *** recovered the best after extreme *** davidiana,*** and *** were more resistant to extreme cold than the other *** warming generally exacerbated the opposite growth patterns of conifer(decline)and broadleaf(increase)*** broadleaf tree species in the old-growth BKF probably will gradually become dominan

关键词： Tree rings Extreme climate Resistance and recovery Broad-leaved and Korean pine mixed forest

MMCo:using multimodal deep learning to detect malicious traffic with noisy labels

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Frontiers of Computer Science 2024年第1期18卷 239-241页

作者： Qingjun yuan Gaopeng GOU Yuefei zhu Yongjuan wang Strategic Support Force Information Engineering University Zhengzhou 450001China Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China

1 Introduction The success of a deep learning-based network intrusion detection systems(NIDS)relies on large-scale,labeled,realistic traffic[1,2].However,automated labeling of realistic traffic,such as by sandbox and rule-based approaches,is prone to errors[3],which in turn affects deep learning-based *** effective schemes for learning with noisy labels(LNL)have been proposed,among which the use of parallel networks for sample selection during training has been shown to be *** is argued that parallel networks can discriminate samples from different perspectives,thus adding additional information to the training *** centerpiece is maintaining disagreement of networks.

关键词： network networks modal

Effects of acupuncture on hypothalamic–pituitary–adrenal axis:Current status and future perspectives

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Journal of Integrative Medicine 2024年第4期22卷 445-458页

作者： Jia-yuan Zheng Jing zhu Yu wang Zhan-zhuang Tian Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceInstitute of Acupuncture ResearchAcademy of Integrative MedicineShanghai Key Laboratory for Acupuncture Mechanism and Acupoint FunctionShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Human Anatomy School of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

The hypothalamic–pituitary–adrenal(HPA) axis is a critical component of the neuroendocrine system,playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus,hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA *** review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture.

关键词： Acupuncture Electroacupuncture Hypothalamic-pituitary-adrenal axis Mechanism Neurotransmitter microRNA

Granular Ionogel Particle Inks for 3D Printed Tough and Stretchable Ionotronics

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Research 2024年第1期2023卷 429-442页

作者： yuan Yao Yue Hui Zhenhua wang Hehao Chen Heng zhu Nanjia Zhou Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024Zhejiang ProvinceChina Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024Zhejiang ProvinceChina School of Chemical Engineering and Advanced Materials the University of AdelaideAdelaide 5005South AustraliaAustralia State Key Laboratory of Fluid Power&Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceCenter for X-MechanicsDepartment of Engineering MechanicsZhejiang UniversityHangzhou 310027China

Ionogels have garnered great attention as promising soft conducting materials for the fabrication of flexible energy storage devices,soft actuators,and ***,the leakage of the ionic liquids,weak mechanical strength,and poor manufacturability have greatly limited their reliability and ***,we propose a new ionogel synthesis strategy by utilizing granular zwitterionic microparticles to stabilize ionic *** ionic liquids swell the microparticles and physically crosslink microparticles via either electronic interaction or hydrogen *** introducing a photocurable acrylic monomer enables the fabrication of double-network(DN)ionogels with high stretchability(>600%)and ultrahigh toughness(fracture energy>10 kJ/m^(2)).The synthesized ionogels exhibit a wide working temperature of−60 to 90℃.By tuning the crosslinking density of microparticles and physical crosslinking strength of ionogels,we synthesize DN ionogel inks and print them into three-dimensional(3D)*** ionogelbased ionotronics are 3D printed as demonstrations,including strain gauges,humidity sensors,and ionic skins made of capacitive touch sensor *** covalently linking ionogels with silicone elastomers,we integrate the ionogel sensors onto pneumatic soft actuators and demonstrate their capacities in sensing large *** our last demonstration,multimaterial direct ink writing is harnessed to fabricate highly stretchable and durable alternating-current electroluminescent devices with arbitrary *** printable granular ionogel ink represents a versatile platform for the future manufacturing of ionotronics.

关键词： crosslinking utilizing gauge