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Low Surface Brightness Galaxies Selected by Different Model Fitting

Research in Astronomy and Astrophysics 2024年第1期24卷 223-236页

作者： Bing-qing Zhang Hong Wu Wei du Pin-Song Zhao min He Feng-Jie Lei Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(disk+bulge):single exponential,single sersic,exponential+deVaucular(exp+deV),and exponential+sérsic(exp+ser).Under the criteria of the B band disk central surface brightness μ_(0,disk)(B)≥22.5 mag arcsec^(-2) and the axis ratio b/a> 0.3,we selected four none-edge-on LSBG samples from each of the models which contain 1105,1038,207,and 75 galaxies,respectively.There are 756 galaxies in common between LSBGs selected by exponential and sersic models,corresponding to 68.42% of LSBGs selected by the exponential model and 72.83% of LSBGs selected by the sersic model,the rest of the discrepancy is due to the difference in obtaining μ_(0) between the exponential and sersic models.Based on the fitting,in the range of 0.5≤n≤1.5,the relation of μ_(0) from two models can be written as μ_(0,sérsic)-μ_(0,exp)=-1.34(n-1).The LSBGs selected by disk+bulge models(LSBG_(2)comps) are more massive than LSBGs selected by single-component models(LSBG_1comp),and also show a larger disk component.Though the bulges in the majority of our LSBG_(2)comps are not prominent,more than 60% of our LSBG_(2)comps will not be selected if we adopt a single-component model only.We also identified 31 giant low surface brightness galaxies(gLSBGs) from LSBG_(2)comps.They are located at the same region in the color-magnitude diagram as other gLSBGs.After we compared different criteria of gLSBGs selection,we find that for gas-rich LSBGs,M_(*)> 10^(10)M_⊙ is the best to distinguish between gLSBGs and normal LSBGs with bulge.

关键词： catalogs galaxies:spiral galaxies:bulges methods:data analysis methods:statistical

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Spatial construction of ultrasmall Pt-decorated 3D spinel oxidemodified N-doped graphene nanoarchitectures as high-efficiency methanol oxidation electrocatalysts

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Rare Metals 2024年第1期43卷 186-197页

作者： Qi Zhang min-min Yan Wen-Fa du Chen-Yu Yin Jian Zhang Lu Yang Yun-qing Kang Hai-Yan He Hua-Jie Huang College of Mechanics and Materials Hohai UniversityNanjing 210098China New Energy Technology Engineering Lab of Jiangsu Province College of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023China International Center for Materials Nanoarchitectonics(WPIMANA) National Institute for Materials ScienceTsukuba 305-0044IbarakiJapan

Direct methanol fuel cell technology recently becomes the focus of both academic and engineering circles,which stimulates the exploitation and utilization of advanced electrode catalysts with high activity and long lifespan.Herein,we demonstrate a robust bottom-up approach to the spatial construction of three-dimensional(3D) spinel manganese-cobalt oxide-modified N-doped graphene nanoarchitectures decorated with ultrasmall Pt nanoparticles(Pt/MnCo_(2)O_(4)-NG) via a controllable selfassembly process.The incorporation of MnCo_(2)O_(4)nanocrystals provides abundant hydroxyl sources to promote the oxidative removal of CO-like byproducts on Pt sites,while the existence of 3D porous N-doped graphene networks facilitates the transportation of both ions and electrons in the hybrid system,thus giving rise to remarkable synergetic coupling effects during the methanol oxidation process.Consequently,the optimized Pt/MnCo_(2)O_(4)-NG nano architecture expres ses exceptional electrocatalytic properties with a large electrochemically active surface area of 99.5 m^(2)·g^(-1),a high mass activity of1508.3 mA·mg^(-1),strong toxicity resistance and reliable long-term durability,which have obvious competitive advantages over those of conventional Pt/carbon black,Pt/carbon nano tube,Pt/graphene,and Pt/N-doped graphene catalysts with the same Pt usage.

关键词： Platinum MnCo_(2)O_(4) 3D graphene Electrocatalysts Methanol oxidation

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Low Surface Brightness Galaxies from BASS+MzLS with Machine Learning

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Research in Astronomy and Astrophysics 2024年第5期24卷 185-197页

作者： Peng-Liang du Wei du Bing-qing Zhang Zhen-Ping Yi min Heand Hong Wu Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China

From ∼5000 deg2 of the combination of the Beijing–Arizona Sky Survey and Mayall z-band Legacy Survey which is also the northern sky region of the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Surveys, we selected a sample of 31,825 candidates of low surface brightness galaxies (LSBGs) with the mean effective surface brightness 24.2 0.60) LSBGs. The blue LSBGs appear spiral, disk or irregular while the red LSBGs are spheroidal or elliptical and spatially clustered. This trend shows that the color has a strong correlation with galaxy morphology for LSBGs. In the spatial distribution, the blue LSBGs are more uniformly distributed while the red ones are highly clustered, indicating that red LSBGs preferentially populate a denser environment than the blue LSBGs. Besides, both populations have a consistent distribution of ellipticity (median epsilon ∼ 0.3), half-light radius (median reff ∼ 4″) and Sérsic index (median n=1), implying the dominance of the full sample by the round and disk galaxies. This sample has definitely extended the studies of LSBGs to a regime of lower surface brightness, fainter magnitude and broader other properties than the previously Sloan Digital Sky Survey-based samples.

关键词： catalogs-galaxies fundamental parameters-galaxies statistics-techniques photometric

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FAM53B promotes pancreatic ductal adenocarcinoma metastasis by regulating macrophage M2 polarization

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1479-1499页

作者： Xuan-Zeng Pei min Cai Da-Wei Jiang Song-Hai Chen qing-qing Wang Hui-min Lu Yi-Fan Lu Department of Hepatological Surgery The First Hospital of JiaxingJiaxing 314000Zhejiang ProvinceChina Department of General Surgery West China Hospital of Sichuan UniversityChengdu 610044Sichuan ProvinceChina

BACKGROUND Our study investigated the role of FAM53B in regulating macrophage M2 polarization and its potential mechanisms in promoting pancreatic ductal adenocarcinoma(PDAC)metastasis.AIM To further investigate the role of FAM53B in regulating macrophage M2 polarization and its potential mechanism in promoting PDAC metastasis.Our goal is to determine how FAM53B affects macrophage M2 polarization and to define its underlying mechanism in PDAC metastasis.METHODS Cell culture and various experiments,including protein analysis,immunohisto-chemistry,and animal model experiments,were conducted.We compared FAM53B expression between PDAC tissues and healthy tissues and assessed the correlation of FAM53B expression with clinical features.Our study analyzed the role of FAM53B in macrophage M2 polarization in vitro by examining the expression of relevant markers.Finally,we used a murine model to study the role of FAM53B in PDAC metastasis and analyzed the potential underlying mechanisms.RESULTS Our research showed that there was a significant increase in FAM53B levels in PDAC tissues,which was linked to adverse tumor features.Experimental findings indicated that FAM53B can enhance macrophage M2 polarization,leading to increased anti-inflammatory factor release.The results from the mouse model further supported the role of FAM53B in PDAC metastasis,as blocking FAM53B prevented tumor cell invasion and metastasis.CONCLUSION FAM53B promotes PDAC metastasis by regulating macrophage M2 polarization.This discovery could lead to the development of new strategies for treating PDAC.For example,interfering with the FAM53B signaling pathway may prevent cancer spread.Our research findings also provide important information for expanding our understanding of PDAC pathogenesis.

关键词： FAM53B Pancreatic ductal adenocarcinoma Tumor metastasis Macrophage polarization

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Paeoniflorin,the Main Monomer Component of Paeonia lactiflora,Exhibits Anti-inflammatory Properties in Osteoarthritis Synovial Inflammation

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Chinese Journal of Integrative Medicine 2024年第5期30卷 433-442页

作者： CHEN Pu ZHOU Jun RUAN An-min MA Yu-feng WANG qing-fu Department of Orthopaedic Surgery Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China Department of Orthopaedic Surgery Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120China Department of Orthopaedic Surgery Beijing Longfu HospitalBeijing 100010China

Objective:To explore the mechanism of paeoniflorin(PF)on osteoarthritis(OA)synovial inflammation from network pharmacology to experimental pharmacology.Methods:Targets of OA were constructed by detecting the database of network database platforms(Therapeutic Target database,Drug Bank and Gene Cards),and the targets of PF were constructed by Pub Chem and Herbal Ingredients'Targets database.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis of these co-targeted genes were conducted via Database for Annotation,Visualization,and Integrated Discovery(DAVID)database,and protein-protein interaction(PPI)networks were conducted via the search tool for the retrieval of interacting genes(STRING)database.Cell counting kit-8(CCK-8)assay was performed to assess the potential toxicity of PF on human OA fibroblast-like synoviocytes(FLS),quantitative real-time polymerase chain reaction(q PCR),enzyme-linked immunosorbent assay(ELISA)and Western blot were used to verify the potential mechanism of PF in synovial inflammation.Results:Twenty-six co-targeted genes were identified.GO enrichment results showed that these co-targeted genes were most likely localized in the cytoplasm,and the biological processes mainly involved'cellular response to hypoxia''lipopolysaccharide(LPS)-mediated signaling pathway'and'positive regulation of gene expression'.KEGG pathway analysis indicated that these co-targeted genes may function through pathways associated with'hypoxia-inducible factor-1(HIF-1)signaling pathway'and'tumornecrosis factor(TNF)signaling pathway'.The PPI network showed that the top 3 hub genes were TP53,TNF,and CASP3.Molecular docking results showed that PF was well docking with TNF.CCK-8 showed no potential toxicity of 10,20 and 50μmol/L PF on human OA FLS.And PF significantly decreased the expression levels of interleukin-1β,interleukin-6,TNF-αmatrix metalloproteinase 13(MMP13),and a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5)and TNF-αin LPS-induced OA FLS.Conclusion:PF exhibited

关键词： paeoniflorin osteoarthritis synovial inflammation tumor necrosis factor-α network pharmacology Paeonia lactiflora

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Electroencephalogram findings in 10 patients with post-stroke epilepsy:A retrospective study

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World Journal of Clinical Cases 2024年第2期12卷 249-255页

作者： Li-min Wen Ran Li Yan-Ling Wang qing-Xia Kong min Xia Clinical Medicine College Jining Medical UniversityJining 272067Shandong ProvinceChina School of Basic Medical Sciences Shandong UniversityJinan 250012Shandong ProvinceChina Department of Neurology The Affiliated Hospital of Jining Medical UniversityJining 272007Shandong ProvinceChina

BACKGROUND Post-stroke epilepsy is a common and easily overlooked complication of acute cerebrovascular disease.Long-term seizures can seriously affect the prognosis and quality of life of patients.Electroencephalogram(EEG)is the simplest way to diagnose epilepsy,and plays an important role in predicting seizures and guiding medication.AIM To explore the EEG characteristics of patients with post-stroke epilepsy and improve the detection rate of inter-seizure epileptiform discharges.METHODS From January 2017 to June 2020,10 patients with post-stroke epilepsy in our hospital were included.The clinical,imaging,and EEG characteristics were collected.The stroke location,seizure type,and ictal and interictal EEG manifestations of the patients with post-stroke epilepsy were then retrospectively analyzed.RESULTS In all 10 patients,epileptiform waves occurred in the side opposite to the stroke lesion during the interictal stage;these manifested as sharp wave,sharp-wave complex,or spike discharges in the anterior head lead of the side opposite to the lesion.CONCLUSION In EEG,epileptiform waves can occur in the side opposite to the stroke lesion in patients with post-stroke epilepsy.

关键词： Post-stroke epilepsy Electroencephalogram Seizure Stroke Slow wave

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Variable projection algorithms with sparse constraint for separable nonlinear models

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Control Theory and Technology 2024年第1期22卷 135-146页

作者： Hui-Lang Xu Guang-Yong Chen Si-qing Cheng min Gan Jing Chen College of Computer and Data Science Fuzhou UniversityFuzhou350116FujianChina Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Intelligent Metro of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Engineering Research Center of Big Data Intelligence Ministry of EducationFuzhou UniversityFuzhou350116FujianChina School of Science Jiangnan UniversityWuxi214122JiangsuChina

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.

关键词： Variable projection(VP) Non-smooth constraint Separable nonlinear models

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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang qing-Lin Cheng Wei Sun Yi Zhao Zhi-min Li Key Lab of ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

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Helmholtz decomposition with a scalar Poisson equation in elastic anisotropic media

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Petroleum Science 2024年第3期21卷 1597-1610页

作者： Xin-Yu Fang Gang Yao qing-qing Zheng Ping-min Zhang Di Wu Feng-Lin Niu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Unconventional Petroleum Research Institute China University of Petroleum (Beijing) Department of Mathematics College of Science China University of Petroleum (Beijing) College of Geophysics China University of Petroleum (Beijing) Department of Earth Environmental and Planetary Sciences Rice University

P-and S-wave separation plays an important role in elastic reverse-time migration. It can reduce the artifacts caused by crosstalk between different modes and improve image quality. In addition, P-and Swave separation can also be used to better understand and distinguish wave types in complex media. At present, the methods for separating wave modes in anisotropic media mainly include spatial nonstationary filtering, low-rank approximation, and vector Poisson equation. Most of these methods require multiple Fourier transforms or the calculation of large matrices, which require high computational costs for problems with large scale. In this paper, an efficient method is proposed to separate the wave mode for anisotropic media by using a scalar anisotropic Poisson operator in the spatial domain.For 2D problems, the computational complexity required by this method is 1/2 of the methods based on solving a vector Poisson equation. Therefore, compared with existing methods based on pseudoHelmholtz decomposition operators, this method can significantly reduce the computational cost. Numerical examples also show that the P and S waves decomposed by this method not only have the correct amplitude and phase relative to the input wavefield but also can reduce the computational complexity significantly.

关键词： Anisotropic media Scalar anisotropic Poisson equation Improved elastic wavefield decomposition

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Effects of acid-rock reaction on physical properties during CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)injection in shale reservoirs

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Petroleum Science 2024年第1期21卷 272-285页

作者： Yi-Fan Wang Jing Wang Hui-qing Liu Xiao-Cong Lv Ze-min Ji National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China Research Institute of Exploration and Development PetroChinaBeijing100083China

"Carbon peaking and carbon neutrality"is an essential national strategy,and the geological storage and utilization of CO_(2)is a hot issue today.However,due to the scarcity of pure CO_(2)gas sources in China and the high cost of CO_(2)capture,CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)is gradually emerging into the public's gaze.CO_(2)has good adsorption properties on shale surfaces,but acidic gases can react with shale,so the mechanism of the CO_(2)-rich IWG-water-shale reaction and the change in reservoir properties will determine the stability of geological storage.Therefore,based on the mineral composition of the Longmaxi Formation shale,this study constructs a thermodynamic equilibrium model of water-rock reactions and simulates the regularity of reactions between CO_(2)-rich IWG and shale minerals.The results indicate that CO_(2)consumed 12%after reaction,and impurity gases in the CO_(2)-rich IWG can be dissolved entirely,thus demonstrating the feasibility of treating IWG through water-rock reactions.Since IWG inhibits the dissolution of CO_(2),the optimal composition of CO_(2)-rich IWG is 95%CO_(2)and 5%IWG when CO_(2)geological storage is the main goal.In contrast,when the main goal is the geological storage of total CO_(2)-rich IWG or impurity gas,the optimal CO_(2)-rich IWG composition is 50%CO_(2)and 50%IWG.In the CO_(2)-rich IWG-water-shale reaction,temperature has less influence on the water-rock reaction,while pressure is the most important parameter.SO2 has the greatest impact on water-rock reaction in gas.For minerals,clay minerals such as illite and montmorillonite had a significant effect on water-rock reaction.The overall reaction is dominated by precipitation and the volume of the rock skeleton has increased by 0.74 cm3,resulting in a decrease in shale porosity,which enhances the stability of CO_(2)geological storage to some extent.during the reaction between CO_(2)-rich IWG-water-shale at simulated temperatures and pressures,precipitation is the main reaction,and shale porosity decrease

关键词： CO_(2)-rich industrial waste gas Geological storage Acid-rock reaction Shale Geochemical modelling

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