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Response of vegetation variation to climate change and human activities in the Shiyang River Basin of China during 2001-2022

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Journal of Arid Land 2024年第8期16卷 1044-1061页

作者： SUN chao BAI Xuelian WANG Xinping zhao Wenzhi WEI Lemin Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Gansu Provincial Academy of Water Sciences Lanzhou 730000China

Understanding the response of vegetation variation to climate change and human activities is critical for addressing future conflicts between humans and the environment,and maintaining ecosystem ***,we aimed to identify the determining factors of vegetation variation and explore the sensitivity of vegetation to temperature(SVT)and the sensitivity of vegetation to precipitation(SVP)in the Shiyang River Basin(SYRB)of China during *** climate data from climatic research unit(CRU),vegetation index data from Moderate Resolution Imaging Spectroradiometer(MODIS),and land use data from Landsat images were used to analyze the spatial-temporal changes in vegetation indices,climate,and land use in the SYRB and its sub-basins(i.e.,upstream,midstream,and downstream basins)during *** regression analysis and correlation analysis were used to explore the SVT and SVP,revealing the driving factors of vegetation *** increasing trends(P<0.05)were detected for the enhanced vegetation index(EVI)and normalized difference vegetation index(NDVI)in the SYRB during 2001-2022,with most regions(84%)experiencing significant variation in vegetation,and land use change was determined as the dominant factor of vegetation ***-significant decreasing trends were detected in the SVT and SVP of the SYRB during *** were spatial differences in vegetation variation,SVT,and *** NDVI and EVI exhibited increasing trends in the upstream,midstream,and downstream basins,the change slope in the downstream basin was lower than those in the upstream and midstream basins,the SVT in the upstream basin was higher than those in the midstream and downstream basins,and the SVP in the downstream basin was lower than those in the upstream and midstream *** and precipitation changes controlled vegetation variation in the upstream and midstream basins while human activities(land use change)dominated vegetation variation in the d

关键词： vegetation variation climate change land use change normalized difference vegetation index(NDVI) enhanced vegetation index(EVI) Shiyang River Basin

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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： zhao-yang Yin Qi-chi Le Yan-chao Jiang Da-zhi zhao Qi-yu Liao Qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

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Beamspace maximum likelihood algorithm based on sum and difference beams for elevation estimation

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Journal of Systems Engineering and Electronics 2024年第3期35卷 589-598页

作者： CHEN sheng zhao Yongbo HU Yili PANG Xiaojiao National Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China

Beamspace super-resolution methods for elevation estimation in multipath environment has attracted significant attention, especially the beamspace maximum likelihood(BML)algorithm. However, the difference beam is rarely used in superresolution methods, especially in low elevation estimation. The target airspace information in the difference beam is different from the target airspace information in the sum beam. And the use of difference beams does not significantly increase the complexity of the system and algorithms. Thus, this paper applies the difference beam to the beamformer to improve the elevation estimation performance of BML algorithm. And the direction and number of beams can be adjusted according to the actual needs. The theoretical target elevation angle root means square error(RMSE) and the computational complexity of the proposed algorithms are analyzed. Finally, computer simulations and real data processing results demonstrate the effectiveness of the proposed algorithms.

关键词： elevation estimation beamspace multipath environment maximum likelihood

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Topology optimization of chiral metamaterials with application to underwater sound insulation

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1119-1138页

作者： chao WANG Honggang zhao Yang WANG Jie ZHONG Dianlong YU Jihong WEN Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha410073China

Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy *** work extends the applications of chiral metamaterials to underwater sound *** chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization *** acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss(STL),while proper stiffness guarantees its robust acoustic performance under a hydrostatic *** proof-of-concept demonstrations,two specimens are fabricated and tested in a water-filled impedance *** results show that,on average,over 95%incident sound energy can be isolated by the specimens in a broad frequency range from 1 k Hz to 5 k Hz,while the sound insulation performance keeps stable under a certain hydrostatic *** work may provide new insights for chiral metamaterials into the underwater applications with sound insulation.

关键词： chiral metamaterial topology optimization underwater sound insulation low acoustic impedance sound transmission loss(STL)

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2D DOA Estimation of Coherent Signals with a Separated Linear Acoustic Vector-Sensor Array

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China Communications 2024年第2期21卷 155-165页

作者： sheng Liu Jing zhao Decheng Wu Yiwang Huang Kaiwu Luo School of Data Science Tongren UniversityTongren 554300China School of Automation Chongqing University of Posts and TelecommunicationsChongqing 400065China

In this paper, a two-dimensional(2D) DOA estimation algorithm of coherent signals with a separated linear acoustic vector-sensor(AVS) array consisting of two sparse AVS arrays is proposed. Firstly,the partitioned spatial smoothing(PSS) technique is used to construct a block covariance matrix, so as to decorrelate the coherency of signals. Then a signal subspace can be obtained by singular value decomposition(SVD) of the covariance matrix. Using the signal subspace, two extended signal subspaces are constructed to compensate aperture loss caused by *** elevation angles can be estimated by estimation of signal parameter via rotational invariance techniques(ESPRIT) algorithm. At last, the estimated elevation angles can be used to estimate automatically paired azimuth angles. Compared with some other ESPRIT algorithms, the proposed algorithm shows higher estimation accuracy, which can be proved through the simulation results.

关键词： acoustic vector-sensor coherent signals extended signal subspace sparse array

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Clinical practice guideline for acupuncture and moxibustion: Female urinary incontinence

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Journal of Integrative Medicine 2024年第3期22卷 258-269页

作者： chao Yang Shan-ze Wang sheng Chen Shuo Du Guan-qun Wang Wei Guo Xiao-long Xie Bi-hui Peng Shi-hao Du Ji-ping zhao Department of Acupuncture and Moxibustion Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China Department of Acupuncture and Moxibustion Guangdong provincial hospital of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Shanghai Ninth People’s Hospital Shanghai Jiao Tong University School of MedicineShanghai 200011China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100700China

Urinary incontinence (UI) is a common problem *** has a major impact on physical and social activities and interpersonal *** is common in women,but is under-reported and *** affects the quality of life of female patients *** and moxibustion have been proposed as potentially effective interventions for female ***,for the benefit of acupuncture practitioners around the world,the World Federation of Acupuncture-moxibustion Societies initiated a project to develop a clinical practice guideline (CPG) for the use of acupuncture and moxibustion to treat female *** CPG was developed according to the Grading of Recommendations Assessment,Development,and Evaluation (GRADE) methodology,referring to the principles of the World Health Organization Handbook for Guideline *** the development of the CPG,the guideline development group (GDG) played an important *** clinical questions,recommendations and therapeutic protocols were all formulated by GDG using the modified Delphi *** CPG contains ten recommendations about the use of acupuncture and moxibustion interventions for ten clinical questions,which include nine conditional recommendations for the intervention and one conditional recommendation for either the intervention or the *** CPG also provides one protocol for conventional filiform needle therapy,two therapy protocols for deep needling stimulation on lumbosacral acupoints,and four moxibustion therapy protocols,based on the protocols presented in randomized controlled trials reviewed by the GDG.

关键词： Acupuncture Clinical practice guideline Female urinary incontinence Moxibustion GRADE

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Clinical practice guideline for acupuncture and moxibustion:Allergic rhinitis

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Journal of Integrative Medicine 2024年第3期22卷 245-257页

作者： Shi-hao Du sheng Chen Shan-ze Wang Guan-qun Wang Shuo Du Wei Guo Xiao-long Xie Bi-hui Peng chao Yang Ji-ping zhao Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100700China Department of Acupuncture and Moxibustion Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China Department of Acupuncture and Moxibustion Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Department of Traditional Chinese Medicine Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China

Acupuncture is one of the most effective complementary therapies for allergic rhinitis(AR)and has been recommended by several clinical practice guidelines(CPGs)for ***,these CPGs mentioned acupuncture without making recommendations for clinical implementation and therapeutic protocols,therefore limiting the applicability of acupuncture therapies for ***,for the benefit of acupuncture practitioners around the world,the World Federation of Acupuncture-moxibustion Societies have initiated a project to develop the CPG for the use of acupuncture and moxibustion to treat *** CPG was developed according to the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)methodology,referring to the principles of the World Health Organization Handbook for Guideline *** the development of the CPG,the guideline development group(GDG)played an important *** clinical questions,recommendations and therapeutic protocols were all formulated by the GDG using the modified Delphi *** CPG contains recommendations for 15 clinical questions about the use of acupuncture and moxibustion *** include one strong recommendation for the intervention based on high-quality evidence,three conditional recommendations for either the intervention or standard care,and 11 conditional recommendations for the intervention based on very low quality of *** CPG also provides one filiform needle acupuncture protocol and five moxibustion protocols extracted based on the protocols presented in randomized controlled trials reviewed by the GDG.

关键词： Clinical practice guideline Allergic rhinitis Acupuncture Moxibustion GRADE

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Synergistic effect and heterointerface engineering of cobalt/carbon nanotubes enhancing electromagnetic wave absorbing properties of silicon carbide fibers

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Nano Research 2024年第9期17卷 8479-8486页

作者： Zixiang zhao Zheyipei Ma Zizhao Ding Yanqiong Liu Mingwei Zhang chao Jiang Institute of Powder Metallurgy Research Central South UniversityChangsha 410083China

To improve the synergistic effect between dielectric and magnetic loss is a practical and effective way in optimizing electromagnetic wave absorbing *** composites of metal particles and carbon ligands derived from metal organic frameworks have gained wide *** this study,Co particles and multiwalled carbon nanotubes(CNT)were successfully synthesized covering the surface of silicon carbide(SiC)fibers,and the morphology,interfaces and electromagnetic wave absorption performance were *** sample SiC@Co/CNT,the minimum reflection loss value can reach-70.22 dB at 11.21 GHz with the thickness of 2.12 *** effective absorbing bandwidth can reach up to 6.03 GHz with the thickness of 1.71 mm,which covers the entire Ku *** brings more interfaces between Co particles and CNTs as well as SiC fibers and Co/C *** interfacial polarization has been hugely enhanced,and the microwave absorbing properties have been *** article reports on the impedance matching of magnetic and non-magnetic components and the heterointerface engineering,which can be effective strategy and inspiration to illustrate the relationship between components,structures and functions of electromagnetic wave absorbing materials.

关键词： metal organic frameworks Co nanocrystals carbon nanotubes Schottky heterointerfaces synergistic effect

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Re-delocalization of localized d-electrons in VO_(2)(R)-VS_(4)hetero-structure enables high performance of rechargeable Mg-ion batteries

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Journal of Magnesium and Alloys 2024年第5期12卷 1830-1840页

作者： Lijiao Zhou chao Shen Xueyang Hou zhao Fang Ting Jin Keyu Xie School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons ***,the reversible Mg^(2+)diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg^(2+)ions and anionic ***,we design and propose a hetero-structural VO_(2)(R)-VS_(4)cathode,in which the re-delocalized d-electrons can effectively shield the polarity of Mg^(2+)***,the electrons should spontaneously transfer from VS_(4)to VO_(2)(R)through the interfaces of hetero-structure due to the lower work function value of VS_(4).Furthermore,the internal electrons transfer lead to the electronic injection into VO_(2)(R)from VS_(4)and the partially broken V-V dimers,indicating the presence of lone pair electrons and charge *** from the shield effect of re-delocalized electrons,and the weakened attraction between cations and O/S anions enables more S^(2-)-S_(2)^(2-)redox groups to participate the electrochemical reactions and compensate the double charge of Mg^(2+)***,VO_(2)(R)-VS_(4)hetero-structure exhibits a high specific capacity of 554 mA h g^(-1)at 50 mA g^(-1).It is believed that the charge re-delocalization of cathode extremely boost the Mg^(2+)ions migration for the high-capacity of MIBs.

关键词： Mg-ion batteries Cathode Charge delocalization Electronic structure Heterostructure

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Microwave excited hyperthermy and catalysis of heterostructured Au/Cu–BTA for effective bacteria killing by accelerating charge separation

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Rare Metals 2024年第10期43卷 5186-5201页

作者： Wen-Jing Zhang Li-Guo Jin Shui-Lin Wu chao-Feng Wang Yu-Feng Zheng zhao-Yang Li Zhen-Duo Cui Hui Jiang sheng-Li Zhu Xiang-Mei Liu School of Materials Science and Engineering the Key Laboratory of Advanced Ceramics and Machining Technology by the Ministry of Education of ChinaTianjin University Biomedical Materials Engineering Research Center Hubei Key Laboratory of Polymer MaterialsMinistry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsSchool of Materials Science&EngineeringHubei University School of Materials Science and Engineering Peking University School of Health Science and Biomedical Engineering Hebei University of Technology

Deep tissue infections caused by pathogenic bacteria seriously threat the lives of *** this study a smart heterostructured Au/Cu-BTA （BTA=1,2,4,5-benzenetetramine） with microwave （MW） response is synthesized via NaBH4reduction of HAuCl4on the ***/Cu-BTA exhibits excellent hyperthermy and dynamics under MW *** MW thermal mechanism of Au/Cu-BTA is attributed to the excellen dielectric loss and polarization of the heterogeneous ***,the surface energy levels of the Cu-BTA interface alleviate the difficulty of electron hopping through multistage ***,MW can excite Cu-BTA to produce free ***,Au nanoparticles rapidly increase electron transfer and inhibit electron-hole ***,the yields of reactive oxygen species can be enhanced for MW dynamic therapy Consequently,under 10 min of MW irradiation,Au/Cu-BTA killed 99.998%±0.001% of Gram-positive Staphylococcus aureus,99.966%±0.014% of methicillin-resistant Staphylococcus aureus,and 96.871%±0.831% of Gram-negative Pseudomonas *** effective MW bacteria-killing strategy designed in this study shows significant potential for application in the MW-responsive treatment of deep tissue infections without antibiotics.

关键词： Anti-infection Antibacterial Microwave therapy

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