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Jamming Assisted Covert Wireless Communication in Multi-Channel Systems

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China Communications 2024年第9期21卷 211-224页

作者： Che Bohan sha.Nan Yang Weiwei Lu Xingbo Gao Chang Army Engineering University of PLA Nanjing 210007China Beijing University of Posts and Telecommunications Beijing 100876China

This paper investigates the jammerassisted multi-channel covert wireless communication(CWC)by exploiting the randomness of sub-channel selection to confuse the *** particular,we propose two sub-channel selection transmission schemes,named random sub-channel selection(RSS)scheme and maximum sub-channel selection(MSS)scheme,to enhance communication *** each proposed scheme,we first derive closed-form expressions of the transmission outage probability(TOP),the average effective rate,and the minimum average detection error probability(DEP).Then,the average effective covert rate(ECR)is maximized by jointly optimizing the transmit power at the transmitter and the number of *** results show that there is an optimal value of the number of sub-channels that maximizes the average *** also find that to achieve the maximum average ECR,a larger number of subchannels are needed facing a stricter covertness constraint.

关键词： covert wireless communication jamming multi-channel system

Gen Z Turns Frequent Zoo Goers

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China Today 2024年第11期73卷 60-63页

作者： sha.BEIYING China Today

Innovative methods in a Nanjing zoo exemplify how China is bringing vitality to *** allowing visitors to watch capybaras,the most loved online animal celebrity now in China,take a bath and telling the background stories of each animal,various zoos in China are using innovative ways to create a new paradise for young urbanites to escape from the hustle and bustle of everyday life,as viewing cute animals can calm their minds and relax their *** China,strolling through a zoo has become a trendy way for the young generation to enjoy their leisure time.

关键词： bringing everyday young

Acceptor-planarized typeⅠphotosensitizer for lipid droplet-targeted two-photon photodynamic therapy by ferroptosis

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Science China Chemistry 2024年第7期67卷 2392-2402页

作者： Jie sha.Weimin Liu Jiasheng Wu Yanping Wang Xuewei Li Haohui Ren Zhi Pang Wenjun Zhang Chun-Sing Lee Pengfei Wang Key Laboratory of Photochemical Conversion and Optoelectronic Materials CityU-CAS Joint Laboratory of Functional Materials and DevicesTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China Center of Super-Diamond and Advanced Films&Department of Materials Science and Engineering City University of Hong KongHong KongChina

Two-photon photodynamic therapy(TP-PDT)has garnered significant attention because of its excellent depth of tissue penetration and high spatiotemporal ***,the limited targeting ability and oxygen dependency of photosensitizers(PSs)significantly hinder the effectiveness of photodynamic therapy in hypoxic tumor ***,we designed and synthesized two lipid droplet(LD)-targeted two-photon PSs(TBPCP and TBCP)by reducing benzene rings to achieve“acceptor planarization”.Notably,acceptor planarization not only enhanced the intramolecular charge transfer but also transferred the photochemical reaction from typeⅡ(TBPCP)to typeⅠ(TBCP).Under the irradiation of 940 nm femtosecond pulsed laser,TBPCP and TBCP showed bright two-photon-excited fluorescence and excellent LD targeting in living *** TBPCP(typeⅡPS),the outstanding TP-PDT efficacy of TBCP(typeⅠPS)under hypoxic conditions could be obtained in both cellular experiments and multicellular tumor spheroids(MCTS)***,both TBPCP and TBCP could induce the lipid peroxidation in the typeⅠor typeⅡPDT due to the location of LD,depleting GSH and inactivating GPX4 to induce nonprogrammed ferroptosis in cells.

关键词： two-photon photodynamic therapy lipid droplet targeting acceptor planarization hypoxia tumor ferroptosis

Percutaneous ultrasound-guided coaxial core needle biopsy for the diagnosis of multiple splenic lesions: A case report

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 616-621页

作者： sha.Hong Pu Wu-Yong-Ga Bao Zhen-Peng Jiang Rui Yang Qiang Lu Department of Medical Ultrasound West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic ***,a definitive diagnosis primarily relies on his-tological *** ultrasound(US)-guided coaxial core needle biopsy(CNB)not only procures sufficient tissue to help clarify the diagnosis,but reduces the incidence of puncture-related *** SUMMARY A 41-year-old female,with a history of pulmonary tuberculosis,was admitted to our hospital with multiple indeterminate splenic ***-scale ultrasono-graphy demonstrated splenomegaly with numerous well-defined hypoechoic *** contrast-enhanced computed tomography(CT)showed an en-larged spleen with multiple irregular-sha.ed,peripherally enhancing,hypodense *** emission CT revealed numerous abnormal hyperglycemia *** imaging findings strongly indicated the possibility of infectious disease as the primary concern,with neoplastic lesions requiring *** obtain the precise pathological diagnosis,the US-guided coaxial CNB of the spleen was ca-rried *** patient did not express any discomfort during the *** Percutaneous US-guided coaxial CNB is an excellent and safe option for obtaining precise splenic tissue samples,as it significantly enhances sample yield for exact pathological analysis with minimum trauma to the spleen parenchyma and sur-rounding tissue.

关键词： Spleen Splenic disease Ultrasound Biopsy Ultrasound-guided coaxial core needle biopsy Case report

Phenotype-Directed DNA Nanomachine for in Situ Analysis of Stem Cell-like Subpopulation in Breast Cancer

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CCS Chemistry 2024年第4期6卷 1034-1046页

作者： Ya Cao Huiru Mao Lingjun sha.Qi Liu Bing Han Jing Zhao Genxi Li Center for Molecular Recognition and Biosensing Shanghai Engineering Research Center of Organ RepairSchool of Life SciencesShanghai UniversityShanghai 200444 State Key Laboratory of Analytical Chemistry for Life Science School of Life SciencesNanjing UniversityNanjing 210023

The cancer stem cell hypothesis provides a basis for prediction of the recurrence and risk of metastasis in breast ***,the unique expression pattern of stemness markers and the presence of nonstem-like cancer cells with varied phenotypes have brought great challenges to the characterization of breast cancer stem *** address these challenges,a phenotype-directed DNA nanomachine has been designed for high-accuracy labeling and in situ analysis of the stem cell-like subpopulation in breast *** key for the design is to use cell surfaceanchored inputs to activate the nanomachine,which undergoes different branch migration pathways such that the signal strand can only be brought onto the cancer cells having the stem cell-like *** sensitive determination and single-step isolation of the stem cell-like subpopulation were achieved by incorporating functional groups into the signal strand such that the nanomachine was successfully applied in a tumor-bearing mouse ***,the approach provides for a substantial improvement in capability for the analysis of the breast cancer stem cell-like subpopulation,and it is expected that the new approach will advance the use of DNA nanomachines in cancer-related studies.

关键词： breast cancer DNA nanomachine stem cell-like subpopulation electrochemical determination single-step isolation phenotypic analysis

Creep property and microstructural evolution of DD11 alloy under high temperature and low stress

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Rare Metals 2024年第2期43卷 810-816页

作者： Yan-Fei Liu Jiang-Bo sha.Yun-Song Zhao Chen-Guang Liu Yuan-Yuan Guo Jian Zhang Yu-Shi Luo School of Materials Science and Engineering Beihang UniversityBeijing100191China Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing100095China

In this paper,the interrupted and ruptured creep tests were carried out in a novel second generation single crystal superalloy named DD11 at 1100℃/130 *** alloy exhibited typical creep curve including primary,steady,and tertiary three creep *** microstructural evolution at different stages of the creep were analyzed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results show that theγ′phases transform into rafted structure at the early stage of the steady creep and keep stable during the steady creep *** the creep goes on,the rafted structure further coarsens and the topological inversion *** addition,at the primary creep,the dislocations mainly move in theγmatrix and pile up in theγ/γ′interface since the matrix channels widen *** formation of the regular interfacial dislocation networks occurs at the early stage of the steady *** the low stress,the dominated deformation mechanism during steady creep stage is the climbing of the〈010〉type edge ***,the effect of the deformation mechanism on creep property was discussed in detail.

关键词： DD11 alloy Creep property Interrupted creep test Rafted structure Deformation mechanism

The beauty of multi-active sites

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cMat 2024年第1期1卷 20-21页

作者： Yu-Qing Wang sha.sha.Guo Zheng Liu School of Materials Science and Engineering Nanyang Technological UniversitySingaporeSingapore Department of Chemistry and Chemical Biology Cornell UniversityIthacaNew YorkUSA CINTRA CNRS/NTU/THALES UMI 3288Research Techno PlazaSingaporeSingapore Institute for Functional Intelligent Materials National University of SingaporeSingaporeSingapore

The Sabatier principle—which states that the best catalyst should be at the peak of the volcano plot,with neither too strong nor too weak intermediate binding strength—plays the golden rule in designing highly active *** instance,Pt with a“just right”hydrogen adsorption free energy(ΔG_(H^(*))=~0 eV)is the most efficient catalyst for hydrogen evolution reaction(HER).^(1)Nevertheless,the pressing demand for renewable energy has sparked a quest beyond the top of the volcano plot,driving the innovation towards more effective,economical.

关键词： catalyst instance adsorption

Mechanical behavior of sliding zone soil under compression considering periodic saturation-drying: example from a giant reservoir landslide

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Journal of Earth Science 2024年

作者： sha.Lu Huiming Tang Liangqing Wang Xuexue Su Bing Lü Badong National Observation and Research Station of Geohazards， China University of Geosciences Faculty of Engineering， China University of Geosciences Wuhan， China

The reservoir landslide undergoes periodic saturation-drying cycles affected by reservoir fluctuation in hydropower project area， leading to the irreversible impact on the landslide materials. Sliding zone is the shearing part in formation of landslide and controls the further development of landslide. The mechanical behavior of sliding zone soil under compression is a crucial factor in the stability analysis in landslide. In this paper， the sliding zone soil from a giant landslide in the biggest hydropower project area， Three Gorges area， is taken as the research case. The particle-size distribution of the sliding zone soil from this landslide is studied and fractal dimension is adopted as representation. Periodic saturation-drying is introduced as the affecting factor on sliding zone soil properties. The triaxial compression test is conducted to reveal the mechanical behavior of the soil， including stress-strain behavior， elastic modulus， failure stress and strength parameters. These behavior of sliding zone soils with different fractal dimensions are studied under the effects of periodic saturation-drying cycles. The normalized stress-strain curves are displayed for further calculation. The data considering saturation-drying cycles are obtained and compared with the experimental results.

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Detection and analysis of landslide geomorphology based on UAV vertical photogrammetry

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Journal of Mountain Science 2024年第4期21卷 1190-1214页

作者： BI Rui GAN Shu YUAN Xiping LI Kun LI Raobo LUO Weidong CHEN Cheng GAO sha.HU Lin ZHU Zhifu School of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China Plication Engineering Research Center of Spatial Information Surveying and Mapping Technology in Plateau and Mountainous Areas Set by Universities in Yunnan Province Kunming 650093China West Yunnan University of Applied Sciences Key Laboratory of Mountain Real Scene Point Cloud Data Processing and Application for Universities in Yunnan ProvinceDali 671006China

High-resolution landslide images are required for detailed geomorphological analysis in complex topographic environment with steep and vertical landslide *** study proposed a vertical route planning method for unmanned aerial vehicles(UAVs),which could achieve rapid image collection based on strictly calculated route *** effectiveness of this method was verified using a DJI Mavic 2 Pro,obtaining high-resolution landslide images within the Dongchuan debris flow gully,in the Xiaojiang River Basin,Dongchuan District,Yunnan,China.A three-dimensional(3D)model was constructed by the structure-from-motion and multi-view stereo(SfM-MVS).Micro-geomorphic features were analyzed through visual interpretation,geographic information system(GIS),spatial analysis,and mathematical statistics *** results demonstrated that the proposed method could obtain comprehensive vertical information on landslides while improving measurement *** 3D model was constructed using the vertically oriented flight route to achieve centimeter-level accuracy(horizontal accuracy better than 6 cm,elevation accuracy better than 3 cm,and relative accuracy better than 3.5 cm).The UAV technology could further help understand the micro internal spatial and structural characteristics of landslides,facilitating intuitive acquisition of surface *** slope of landslide clusters ranged from 36°to 72°,with the majority of the slope facing east and *** elevation levels were relatively consistent while middle to lower elevation levels gradually decreased from left to right with significant variations in lower elevation *** the rainy season,surface runoff was abundant,and steep topography exacerbated changes in surface *** route method is suitable for unmanned aerial vehicle(UAV)landslide surveys in complex mountainous *** geomorphological analysis methods used will provide references for identifying and describing topographic

关键词： UAV Landslide Vertical route SfM-MVS Topographic features