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Inelastic Interaction of Double-Valley Dark Solitons for the Hirota Equation

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Chinese Physics Letters 2021年第9期38卷 1-5页

作者： Xiao-Man Zhang Yan-Hong Qin li-ming ling li-Chen Zhao School of Mathematics South China University of TechnologyGuangzhou 510640China School of Physics Northwest UniversityXi’an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127China Peng Huanwu Center for Fundamental Theory Xi’an 710127China

For a scalar integrable model,it is generally believed that the solitons interact with each other elastically,for instance,multi-bright solitons from the nonlinear Schrodinger equation and the Korteweg-de Vries equation,*** obtain double-valley dark solitons from the defocusing Hirota equation by the Darboux ***,we report a remarkable phenomenon for the inelastic interaction of the double-valley dark solitons,in contrast to the solitons interacting with each other elastically for a scalar integrable model in previous ***,we give the explicit conditions for the elastic collision based on the asymptotic analysis *** is shown that the double-valley dark solitons could also admit elastic interaction under the special parameters settings.

关键词： solitons integrable equation

Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3071-3088页

作者： Chun-ming Wu Jin Lei Wu-Kai liu Mei-ling Ren ling-li Ran Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology School of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Biomedical Engineering Taiyuan University of TechnologyTaiyuan030600China

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model *** algorithm is validated in detail on two vessel *** comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance ***,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO ***,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

关键词： Unmanned ships R_YOLO EMA CSPStage YOLOv8s

The Orthogonal Bases of Exponential Functions Based on Moran-Sierpinski Measures

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1804-1824页

作者： Qi Rong DENG Xing Gang HE ming Tian li Yuan ling YE School of Mathematics and Statistics Center for Applied Mathematics of Fujian Province&Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Normal UniversityFuzhou350117P.R.China School of Mathematics and Statistics Key Lab NAA-MOE and Hubei Key Lab-Math.Sci.Central China Normal UniversityWuhan430079P.R.China School of Mathematical Sciences&South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou510631P.R.China

Let An∈M2(ℤ)be integral matrices such that the infinite convolution of Dirac measures with equal weightsμ{A_(n),n≥1}δA_(1)^(-1)D*δA_(1)^(-1)A_(2)^(-2)D*…is a probability measure with compact support,where D={(0,0)^(t),(1,0)^(t),(0,1)^(t)}is the Sierpinski *** prove that there exists a setΛ⊂ℝ2 such that the family{e2πi〈λ,x〉:λ∈Λ} is an orthonormal basis of L^(2)(μ{A_(n),n≥1})if and only if 1/3(1,-1)A_(n)∈Z^(2)for n≥2 under some metric conditions on A_(n).

关键词： Moran-Sierpinski measures orthonormal basis of exponential functions self-affine measures spectral measures

Ginsenoside Rd Induces Differentiation of Myeloid Leukemia Cells via Regulating ERK/GSK-3βSignaling Pathway

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Chinese Journal of Integrative Medicine 2024年第7期30卷 588-599页

作者： JIANG Yu-xia ZHAO Yan-na YU Xiao-ling YIN li-ming Department of Hematology Tongde Hospital of Zhejiang ProvinceHangzhou310012China Institute of Hematology Research the First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou310006China

Objective To investigate the role of ginsenoside Rd(GRd)in acute myeloid leukemia(AML)cell *** AML cells were treated with GRd(25,50,100 and 200µg/mL),retinoic acid(RA,0.1g/L)and PD98059(20 mg/mL)for 72 h,cell survival was detected by methylthiazolyldiphenyl-tetrazolium bromide and colony formation assays,and cell cycle was detected by flow *** morphology and differentiation were observed by Wright-Giemsa staining,peroxidase chemical staining and cellular immunochemistry assay,*** protein expression levels of GATA binding protein 1(GATA-1),purine rich Box-1(PU.1),phosphorylated-extracellular signal-related kinase(p-ERK),ERK,phosphorylated-glycogen synthase kinase-3β(p-GSK3β),GSK3βand signal transducer and activator of transcription 1(STAT1)were detected by Western ***-six mice were randomly divided into 3 groups using a random number table:model control group(non-treated),GRd group[treated with 200 mg/(kg·d)GRd]and homoharringtonine(HTT)group[treated with 1 mg/(kg·d)HTT].A tumor-bearing nude mouse model was established,and tumor weight and volume were *** of subcutaneous tumor tissue were observed after hematoxylin and eosin ***1 and GATA-1 expressions were detected by immunohistochemical *** The cell survival was inhibited by GRd in a dose-dependent manner and GRd caused G0/G1 cell arrest(plicited upregulation of p-ERK,p-GSK-3βand STAT1 expressions in cells,and reversed the effects of PD98059 on inhibiting the expressions of peroxidase,GATA-1 and PU.1(P<0.05).After GRd treatment,tumor weight and volume of mice were decreased,and tumor cells underwent massive apoptosis and necrosis(P<0.05).WT1 level was decreased,and GATA-1 level was significantly increased in subcutaneous tumor ti

关键词： ginsenoside Rd myeloid leukemia survival differentiation extracellular signal-related kinase signaling pathway

Comparative DNA methylation reveals epigenetic adaptation to high altitude in snub-nosed monkeys

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Zoological Research 2024年第5期45卷 1013-1026页

作者： ling Wang Wei-Qiang liu Juan Du Meng li Rui-Feng Wu ming li Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China

DNA methylation plays a crucial role in environmental ***,using whole-genome bisulfite sequencing,we generated comprehensive genome-wide DNA methylation profiles for the high-altitude Yunnan snub-nosed monkey(Rhinopithecus bieti)and the closely related golden snub-nosed monkey(***).Our findings indicated a slight increase in overall DNA methylation levels in golden snub-nosed monkeys compared to Yunnan snub-nosed monkeys,suggesting a higher prevalence of hypermethylated genomic regions in the *** genomic methylation analysis demonstrated that genes associated with differentially methylated regions were involved in membrane fusion,vesicular formation and trafficking,hemoglobin function,cell cycle regulation,and neuronal *** results suggest that the high-altitude-related epigenetic modifications are extensive,involving a complete adaptation process from the inhibition of single Ca^(2+)channel proteins to multiple proteins collaboratively enhancing vesicular function or inhibiting cell differentiation and *** assays demonstrated that overexpression or down-regulation of candidate genes,such as SNX10,TIMELESS,and CACYBP,influenced cell viability under stress ***,this research suggests that comparing DNA methylation across closely related species can identify novel candidate genomic regions and genes associated with local adaptations,thereby deepening our understanding of the mechanisms underlying environmental adaptations.

关键词： Snub-nosed monkeys Whole-genome bisulfite sequencing DNA methylation High-altitude adaptation

Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue Ruan Xiu-Fang li Meng-Ya Guo Mei Chen ming Lv Rui li Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index

Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： Jing-Sheng Ma ming-Zai Wu ling Chen li-Xing Zhang Ying Xiong Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第02期34卷 376-388页

作者： ling Zhang Yinglong li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

Applications of mercury stable isotopes for tracing volcanism in the geologic record

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Science China Earth Sciences 2024年第5期67卷 1436-1458页

作者： Qing GONG ming-Xing ling Wang ZHENG State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China

Mercury(Hg)enrichments in ancient sediments have been used as a proxy of volcanism,especially large igneous province(liP)***,considering the existence of other potential Hg sources besides volcanoes and the diverse factors(e.g.,organic matters,clay minerals,sulfide minerals and Fe oxides)that can affect Hg sequestration,there are considerable uncertainties to simply regard sedimentary Hg anomalies as signatures of volcanic *** stable isotopes,a promising tool for tracing the origins and transformations of Hg,have been increasingly used for determining the causes of Hg spikes and understanding the geochemical behavior of Hg in the geologic *** date,lots of researches have applied Hg concentrations and Hg isotopes to identify liP volcanisms linking with significant geological events such as mass extinctions,ocean anoxic events and other environmental perturbations that mainly occurred in the ***,the results in previous studies clearly show that not all Hg enrichments are derived from volcanic inputs,which emphasize the need for more caution in using Hg as a fingerprint of *** a better understanding of Hg isotopes in the future,there will be important implications for Hg isotopes to reconstruct volcanic activities in the rock records and their impacts on biological evolution.

关键词： Mercury stable isotopes Large igneous province Mass extinction event Ocean anoxic event