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An Efficient Local Radial Basis Function Method for Image Segmentation Based on the Chan-Vese Model

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 1119-1134页

作者： Shupeng Qiu Chujin Lin wei zhao School of Mathematics and Statistics Guangdong University of TechnologyGuangzhou510520China

In this paper,we consider the Chan–Vese(C-V)model for image segmentation and obtain its numerical solution accurately and *** this purpose,we present a local radial basis function method based on a Gaussian kernel(GA-LRBF)for spatial *** to the standard radial basis functionmethod,this approach consumes less CPU time and maintains good stability because it uses only a small subset of points in the whole computational ***,since the Gaussian function has the property of dimensional separation,the GA-LRBF method is suitable for dealing with isotropic ***,a numerical scheme that couples GA-LRBF with the fourth-order Runge–Kutta method is applied to the C-V model,and a comparison of some numerical results demonstrates that this scheme achieves much more reliable image segmentation.

关键词： Image segmentation Chan–Vese model local radial basis functionmethod Gaussian kernel Runge–Kuttamethod

Prognosis prediction and immune microenvironment features of breast cancer indicated by a cuproptosis-associated long non-coding RNA signature

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Genes & Diseases 2024年第5期11卷 66-69页

作者： Siyi Liu Juanchan Huang wei zhao Department of Radiation Oncology Guangxi Medical University Cancer HospitalNanningGuangxi 530000China Guangxi Medical University NanningGuangxi 530000China Department of Oncology Affiliated Wuming Hospital of Guangxi Medical UniversityNanningGuangxi 530000China

Cuproptosis is a newly discovered type of programmed cell death that involves the depletion of intracellular copper and is not influenced by other inhibitors of programmed cell *** modality was first identified and named by Tsvetkov et al in the previous year.1 To further explore the relationship between cuproptosis,the tumor microenvironment,immunotherapy,and prognosis for breast cancer(BC),the expression patterns of 19 cuproptosis-related long non-coding RNAs(lncRNAs)were determined using data from the Cancer Genome Atlas(TCGA).

关键词： breast cancer microenvironment

The Impact of Sulfur Fertilizer Concentration on the Nutrient Concentration of Parts of the Soybean Plant

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PHYTON-INTERNATIONAL JOURNAL OF EXPERIMENTAL BOTANY 2024年第8期93卷 1851-1873页

作者： wei, Xinhe zhao, wei Sun, Yanbin Dong, Shoukun Northeast Agr Univ Coll Agr Agr Coll Harbin 150030 Peoples R China

Soybean is a crucial crop utilized for both food and oil production, with balanced crop nutrition being a key determinant of soybean yield throughout its growth cycle. Sulfur, an essential nutrient for crop growth, substantially impacts soybean yield. In this study, two soybean cultivars, Laidou 2 and Hefeng 55, were used to study the changes in nitrogen, phosphorus, potassium, and sulfur contents in soybean plants at different growth stages. Additionally, the effects of dry matter accumulation under fi ve different sulfur levels were examined. The results showed that the sulfur levels had varying effects on the nitrogen, phosphorus, potassium, and sulfur contents and accumulation in different parts of the soybean plants. There were marked differences in the accumulation and distribution of dry matter in different parts of the soybean plant. Soybean dry matter weight shows the best overall performance under the S80 treatment. With increasing sulfur nutrition, the nitrogen, phosphorus, potassium, and sulfur contents in various plant parts exhibited an unimodal trend, reaching maximum values when the sulfur content was 80 mg/L. This study elucidates the dynamic changes in nutrient elements in soybeans under different sulfur levels and is important in guiding the rational application of sulfur fertilizers in agricultural production.

关键词： Interaction sulfur elemental content TRIFOLIUM-REPENS AVAILABILITY ACQUISITION METABOLISM SOIL

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： Yao Pan Xiaofeng Sun wei zhao Xin Li Yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power

Molecular dynamics simulation study of nitrogen vacancy color centers prepared by carbon ion implantation into diamond

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NANOTECHNOLOGY AND PRECISION ENGINEERING 2024年第3期7卷 71-78页

作者： zhao, wei Xu, Zongwei Wang, Pengfei Chen, Hanyi Tianjin Univ State Key Lab Precis Measuring Technol & Instrumen Tianjin 300072 Peoples R China Univ Sci & Technol China Dept Modern Phys Hefei 230026 Peoples R China

Nitrogen vacancy (NV) color centers in diamond have useful applications in quantum sensing and fluorescent marking. They can be generated experimentally by ion implantation, femtosecond lasers, and chemical vapor deposition. However, there is a lack of studies of the yield of NV color centers at the atomic scale. In the molecular dynamics simulations described in this paper, NV color centers are prepared by ion implantation in diamond with pre-doped nitrogen and subsequent annealing. The differences between the yields of NV color centers produced by implantation of carbon (C) and nitrogen (N) ions, respectively, are investigated. It is found that C-ion implantation gives a greater yield of NV color centers and superior location accuracy. The effects of different pre-doping concentrations (400-1500 ppm) and implantation energies (1.0-3.0 keV) on the NV color center yield are analyzed, and it is shown that a pre-doping concentration of 1000 ppm with 2 keV C-ion implantation can produce a 13% yield of NV color centers after 1600 K annealing for 7.4 ns. Finally, a brief comparison of the NV color center identification methods is presented, and it is found that the error rate of an analysis utilizing the identify diamond structure + coordination analysis method is reduced by about 7% compared with conventional identification methods.

关键词： NV color center Ion implantation Molecular dynamics (MD) simulation Yield enhancement NV CENTERS

High‑Entropy Layered Oxide Cathode Enabling High‑Rate for Solid‑State Sodium‑Ion Batteries

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Nano-Micro Letters 2024年第1期16卷 160-171页

作者： Tianxun Cai Mingzhi Cai Jinxiao Mu Siwei zhao Hui Bi wei zhao Wujie Dong Fuqiang Huang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Zhongke Institute of Strategic Emerging Materials Yixing 214213JiangsuPeople’s Republic of China

Na-ion O3-type layered oxides are prospective cathodes for Na-ion batteries due to high energy density and ***,such cathodes usually suffer from phase transitions,sluggish kinetics and air instability,making it difficult to achieve high performance solid-state sodium-ion ***,the high-entropy design and Li doping strategy alleviate lattice stress and enhance ionic conductivity,achieving high-rate performance,air stability and electrochemically thermal stability for Na_(0.95)Li_(0.06)Ni_(0.25)Cu_(0.05)Fe_(0.15)Mn_(0.49)O_(2).This cathode delivers a high reversible capacity(141 mAh g^(−1)at 0.2C),excellent rate capability(111 mAh g^(−1)at 8C,85 mAh g^(−1)even at 20C),and long-term stability(over 85%capacity retention after 1000 cycles),which is attributed to a rapid and reversible O3–P3 phase transition in regions of low voltage and suppresses phase ***,the compound remains unchanged over seven days and keeps thermal stability until 279℃.Remarkably,the polymer solid-state sodium battery assembled by this cathode provides a capacity of 92 mAh g^(−1)at 5C and keeps retention of 96%after 400 *** strategy inspires more rational designs and could be applied to a series of O3 cathodes to improve the performance of solid-state Na-ion batteries.

关键词： High-entropy High-rate performance Li-TM interaction Air stability O3 layered oxide cathode

Diet and monensin influence the temporal dynamics of the rumen microbiome in stocker and finishing cattle

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Journal of Animal Science and Biotechnology 2024年第2期15卷 733-748页

作者： Jianmin Chai Caleb P.weiss Paul A.Beck wei zhao Ying Li Jiangchao zhao Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding College of Life Science and EngineeringFoshan UniversityFoshanChina Division of Agriculture Department of Animal ScienceUniversity of ArkansasFayettevilleARUSA Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA Institute of Feed Research of Chinese Academy of Agricultural Sciences Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural AffairsBeijing 100193China

Background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen *** the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were *** calves were then transported to a feedlot and received similar finishing diets with or without *** microbial samples were collected on d 0,28,85 during the stocker stage(S0,S28 and S85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(F0,F14,F28,F56,Pre-Ba,and Final).The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was *** Higher alpha diversity,including the number of observed bacterial features and the Shannon index,was observed in the stocker phase compared to the finishing *** bacterial amplicon sequence variants(ASVs)differentiating different sampling time points were *** treatments during the stocker stage temporally impact the dynamics of rumen *** example,shared bacteria,including Bacteroidales(ASV19)and Streptococcus infantarius(ASV94),were significantly higher in hay rumen on S28,S85,and F0,while Bacteroidaceae(ASV11)and Limivicinus(ASV15)were more abundant in *** affected rumen microbial composition at a specific *** to feedlot significantly influenced microbiome structure and diversity in hay-fed *** taxa associated with body weight were classified,and core microbiotas interacted with each other during the *** In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding *** at the stocker phase may t

关键词： Beef cattle Diet Feedlot phase Monensin Next-generation sequencing Rumen microbiota Stocker

Effect of Incoming Vortex on Secondary Flows in Turbine Cascades with Planar and Non-Axisymmetric Endwall

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Journal of Thermal Science 2024年第1期33卷 138-157页

作者： CAO Zhiyuan WANG Chuxuan SONG Zhigao GAO Xi zhao wei LIU Bo School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China National Key Laboratory of Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi'an 710072China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100080China

Non-Axisymmetric Endwall Profiling(NAEP) is commonly utilized in turbines to eliminate secondary ***,most of the NAEP methods consider a single-blade row environment without incorporating the effect of the stage *** paper aims to investigate the influence mechanism of the incoming vortex on the endwall secondary flow structures of NAEP in a highly loaded turbine *** model the incoming vortex in a stage environment,this study considers a half-delta wing as the vortex generator at the upstream of the turbine *** NAEP is then carried out for a highly loaded turbine cascade with an in-house numerical optimization design platform subject to no incoming *** simulation is also carried out under the influence of the incoming vortex for the turbine cascades with both planar and non-axisymmetric *** paper furthers investigated the pitchwise effect of the incoming vortex on the near endwall secondary *** results indicate that the NAEP effectively improves the endwall secondary flow of the turbine cascade,where the total pressure loss coefficient and the secondary kinetic energy(SKE) are reduced by 7.3%,and 45.7%,*** is further seen that with the incoming vortex,the NAEP achieves a considerable control effect on the endwall secondary flow of the turbine *** incoming vortex,the NAEP can still achieve considerable control effect on the endwall secondary flow of the turbine cascade;the averaged reductions of loss coefficient and SKE are 7.8% and 14.2%,*** some pitchwise locations,incoming vortex can suppress the convection of cross-passage flow toward the suction corner greatly and reduce the loss coefficient of the baseline *** incoming vortex at 4/7 pitch impinged right at the blade leading edge,leading to the generation of low-momentum fluid,which increased the size and the strength of the horseshoe *** all the pitchwise locations,NAEP can suppress the seco

关键词： non-axisymmetric endwall secondary flow incoming vortex passage vortex stage environment

Infrared microspectroscopy beamline BL06B at SSRF

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Nuclear Science and Techniques 2024年第1期35卷 10-17页

作者： Te Ji Hua-Chun Zhu wei-wei Peng Jie Wang Hong-wei zhao Ai-Guo Li Min Chen Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By 2021, it became accessible to users. The synchrotron radiation infrared(SRIR) source included edge radiation(ER) and bending magnet radiation(BMR). The extracted angles in the horizontal and vertical directions were 40 and 20 mrad, respectively. The photon flux, spectral resolution, and focused spot size were measured at the BL06B endstation, and the experimental results were consistent with theoretical calculations. SRIR light has a small divergence angle, high brightness, and a wide wavelength range. As a source of IR microscopy, it can easily focus on a diffraction-limited spatial resolution with a high signal-to-noise ratio(SNR). The BL06B endstation can be applied in a wide range of research fields, including materials, chemistry, biology, geophysics, and pharmacology.

关键词： Synchrotron radiation Infrared beamline Infrared microspectroscopy