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Revisiting gamma-ray burst afterglows with time-dependent parameters

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Research in Astronomy and Astrophysics 2018年第2期18卷 53-72页

作者： Chao Yang Yuan-Chuan Zou wei Chen Bin Liao wei-hua lei Yu Liu School of Physics Huazhong University of Science and Technology

The relativistic external shock model of gamma-ray burst （GRB） afterglows has been estab- lished with five free parameters, i.e., the total kinetic energy E, the equipartition parameters for electrons ee and for the magnetic field eB, the number density of the environment n and the index of the power- law distribution of shocked electrons p. A lot of modified models have been constructed to consider the variety of GRB afterglows, such as： the wind medium environment by letting n change with radius, the energy injection model by letting kinetic energy change with time and so on. In this paper, by as- suming all four parameters （except p） change with time, we obtain a set of formulas for the dynamics and radiation, which can be used as a reference for modeling GRB afterglows. Some interesting results are obtained. For example, in some spectral segments, the radiated flux density does not depend on the number density or the profile of the environment. As an application, through modeling the afterglow of GRB 060607A, we find that it can be interpreted in the framework of the time dependent parameter model within a reasonable range.

关键词：（stars：） gamma.ray burst： general -- methods： analytical

A two-component jet model based on the Blandford-Znajek and Blandford-Payne processes

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Research in Astronomy and Astrophysics 2012年第7期12卷 817-828页

作者： wei Xie wei-hua lei Yuan-Chuan Zou Ding-Xiong Wang Qingwen Wu Jiu-Zhou Wang School of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics and Astronomy University of Nevada Las Vegas 4505 MarylandParkway Box 454002 Las Vegas NV89154-4002 USA

We propose a two-component jet model consistent with the observations of several gamma ray bursts （GRBs） and active galactic nuclei （AGNs）. The jet consists of inner and outer components, which are supposed to be driven by the Blandford- Znajek （BZ） and Blandford-Payne （BP） processes, respectively. The baryons in the BP jet are accelerated centrifugally via the magnetic field anchored in the accretion disk. The BZ jet is assumed to be entrained in a fraction of accreting matter leaving the inner edge of the accretion disk, and the baryons are accelerated in the conversion from electromagnetic energy to kinetic energy. By fitting the Lorentz factors of some GRBs （GRB 030329, GRB 051221A and GRB 080413B） and AGNs （Cen A, Mkn 501 and Mkn 421） with this model, we constrain the physical parameters related to the accretion and outflow of these two kinds of objects. We conclude that the spine/sheath structure of the jet from these sources can be interpreted naturally by the BZ and BP processes.

关键词： gamma rays： bursts -- galaxies： jets -- accretion accretion disks --magnetic fields -- jets and outflows

1374例椅旁CAD/CAM全瓷修复体的类型及颜色调查

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上海口腔医学 2024年第2期33卷 200-204页

作者：金夏悦余润平花葳蕾黄慧上海交通大学医学院附属第九人民医院口腔修复科上海交通大学口腔医学院国家口腔医学中心国家口腔疾病临床医学研究中心上海市口腔医学重点实验室上海市口腔医学研究所上海200011

目的:分析椅旁CAD/CAM全瓷修复体的类型及使用的全瓷材料的颜色区间,为指导临床椅旁全瓷修复的应用及材料的颜色选择提供参考。方法:收集整理2021年1月—2021年12月上海交通大学医学院附属第九人民医院口腔修复科使用椅旁CAD/CAM切削IPS... 详细信息

目的:分析椅旁CAD/CAM全瓷修复体的类型及使用的全瓷材料的颜色区间,为指导临床椅旁全瓷修复的应用及材料的颜色选择提供参考。方法:收集整理2021年1月—2021年12月上海交通大学医学院附属第九人民医院口腔修复科使用椅旁CAD/CAM切削IPS e.max CAD材料的修复体相关数据。对修复体的数量、类型和全瓷材料的颜色分布进行调查,分析修复体的类型和材料的颜色分布频率。结果:共纳入1374枚修复体,其中,冠修复体最多,624例,占总修复体的45.41%;贴面516例,占37.55%;嵌体219例,占15.94%;固定桥均为粘接桥,数量最少,仅15例,占1.09%。修复材料的选择方面,低透(LT)瓷块的使用频率显著高于其他透明度的瓷块;A色系为使用频率最高的颜色。贴面最常选用的瓷块为LTA2和LTA1;嵌体使用最多的为LTA3;冠使用最多的为LTA2和LTA3;固定桥使用的瓷块均为LT色系,A3色占多数。结论:使用IPS e.max CAD材料制作的椅旁CAD/CAM全瓷修复体已广泛用于临床,修复体类型包括贴面、嵌体、冠和粘接固定桥。临床最常用的IPS e.max CAD瓷块为LTA2、LTA3、LTA1,这对基层医院的临床修复决策及瓷块储备具有一定的指导意义。

关键词：椅旁CAD/CAM IPS e.max CAD 二硅酸锂玻璃陶瓷透明度

Extending the correlation of L_R-L_X to gamma-ray bursts

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Research in Astronomy and Astrophysics 2015年第5期15卷 617-622页

作者： Jing L Jing-Wen Xing Yuan-Chuan Zou wei-hua lei Qing-Wen Wu Ding-Xiong Wang GXU-NAOC Center for Astrophysics and Space Sciences Department of PhysicsGuangxi University Guangxi Key Laboratory for Relativistic Astrophysics School of Physics Huazhong University of Science and Technology

The well-known correlation between radio luminosity （LR） and X-ray luminosity （Lx）, LR/LX 10^-5, holds for a variety of objects, such as active galactic nuclei, Galactic black holes, solar flares and cool stars. Here we extend the relation to gamma-ray bursts （GRBs） and find that the GRBs also obey a similar LR - LX relation, with a slightly different slope of LR ∝ LX^1.1. This relation implies that the explosions that occur on different scales may have a common underlying origin.

关键词： gamma-ray bursts general -- quasars general -- stars black holes

Revisiting the island of hexadecapoledeformation nuclei in the A≈150 mass region:focusing on the model application to nuclear shapes and masses

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Communications in Theoretical Physics 2024年第2期76卷 74-88页

作者： Xiao-Yang wei hua-lei Wang Zhen-Zhen Zhang Min-Liang Liu School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Based on the potential-energy-surface calculation,the impact of different deformation degrees of freedom on a single-particle structure and binding energies in nuclei around^(152)Nd,located on one of the hexadecapole-deformation islands,is analyzed in a multi-dimensional deformation space.Various energy maps,curves and tables are presented to indicate nuclear properties.The calculated equilibrium deformations and binding energies with different potential parameters are compared with experimental data and other theories.It is found that the inclusion of the hexadecapole deformations,especially the axial one,can improve the theoretical description of both nuclear shapes and masses.In addition,our calculated potential-energy curve shows that a critical deformation-point,β_(2)≈0.4,exists—the triaxial(hexadecapole)deformation effect can be neglectable but the hexadecapole(triaxial)one plays an important role before(after)such a critical point.

关键词： hexadecapole deformation binding energy potential-energy-surface calculation nuclear property

Nano polystyrene microplastics could accumulate in Nile tilapia(Oreochromis niloticus):Negatively impacts on the intestinal and liver health through water exposure

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Journal of Environmental Sciences 2024年第3期137卷 604-614页

作者： Di Wu Xing Lu Li-Xue Dong Juan Tian Jin Deng lei wei hua Wen Shan Zhong Ming Jiang School of Basic Medical Sciences Wuhan UniversityWuhan 430071China Key Laboratory of Freshwater Biodiversity Conservation Ministry of Agriculture and Rural AffairsYangtze River Fisheries Research InstituteChinese Academy of Fishery SciencesWuhan 430223China Hubei Province Key Laboratory of Allergy and Immunology Wuhan 430071China

Microplastics(MPs)have become a significant concern for their potential toxicity.However,the correlation between the size of plastic particles and their toxicity remains inconclusive.Here,we investigate the toxic effects of different sizes(80 nm,800 nm,8μm and 80μm)polystyrene MPs(PS-MPs)on the model organism Nile tilapia(Oreochromis niloticus).The results of bioluminescent imaging indicate that the 80 nm PS-MPs are more likely to invade the body.H&E staining shows severe damage on the intestinal villi and distinct hepatic steatosis in the 80 nm group.Ed U labeling shows that the proliferation activity of intestinal and liver cells reduces significantly in the 80 nm group.The gut microbiome analysis shows a severe imbalance of gut microbiota homeostasis in the 80 nm group.The analysis of liver transcriptomics and metabolomics shows that the liver lipid metabolism is disordered in the 80 nm group.In conclusion,this study confirms that the 80 nm PS-MPs are more likely to induce intestinal and liver toxicity.All the above lay the foundation for further study on the pathological damage of MPs to other organisms.

关键词： Microplastics(MPs) Intestinal toxicity Liver toxicity Gut microbiome Lipid metabolism

Predictive model using four ferroptosis-related genes accurately predicts gastric cancer prognosis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2018-2037页

作者： Li Wang wei-hua Gong Department of Emergency The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Department of Surgery The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310052Zhejiang ProvinceChina

BACKGROUND Gastric cancer(GC)is a common malignancy of the digestive system.According to global 2018 cancer data,GC has the fifth-highest incidence and the thirdhighest fatality rate among malignant tumors.More than 60%of GC are linked to infection with Helicobacter pylori(H.pylori),a gram-negative,active,microaerophilic,and helical bacterium.This parasite induces GC by producing toxic factors,such as cytotoxin-related gene A,vacuolar cytotoxin A,and outer membrane proteins.Ferroptosis,or iron-dependent programmed cell death,has been linked to GC,although there has been little research on the link between H.pylori infection-related GC and ferroptosis.AIM To identify coregulated differentially expressed genes among ferroptosis-related genes(FRGs)in GC patients and develop a ferroptosis-related prognostic model with discrimination ability.METHODS Gene expression profiles of GC patients and those with H.pylori-associated GC were obtained from The Cancer Genome Atlas and Gene Expression Omnibus(GEO)databases.The FRGs were acquired from the FerrDb database.A ferroptosis-related gene prognostic index(FRGPI)was created using least absolute shrinkage and selection operator–Cox regression.The predictive ability of the FRGPI was validated in the GEO cohort.Finally,we verified the expression of the hub genes and the activity of the ferroptosis inducer FIN56 in GC cell lines and tissues.RESULTS Four hub genes were identified(NOX4,MTCH1,GABARAPL2,and SLC2A3)and shown to accurately predict GC and H.pylori-associated GC.The FRGPI based on the hub genes could independently predict GC patient survival;GC patients in the high-risk group had considerably worse overall survival than did those in the low-risk group.The FRGPI was a significant predictor of GC prognosis and was strongly correlated with disease progression.Moreover,the gene expression levels of common immune checkpoint proteins dramatically increased in the highrisk subgroup of the FRGPI cohort.The hub genes were also confirmed to be highly overexpressed in GC cell line

关键词： Ferroptosis Gastric cancer Helicobacter pylori infection Immune checkpoint protein Prognostic model Ferroptosis-related gene prognostic index

Cyclohexanol optimizes Pt/ionomer interface in fuel cell cathodes

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Science China Chemistry 2024年第2期67卷 417-419页

作者： lei Tong Hai-wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

This highlight is based on a recent article published in Nature Catalysis, in which wei's group [1] from Chongqing University proposes a novel approach to enhance the performance of proton exchange membrane fuel cells(PEMFCs)by adjusting the interface between Pt and ionomer in the cathode catalyst layer. Their strategy involves adding cyclohexanol to the cathode catalyst ink to impede the adsorption of sulfonate groups from the ionomer onto Pt nanoparticles, which results in the release of Pt activity sites and a significant improvement in the mass transport efficiency.

关键词： interface catalyst adding

Advances of biomarkers in nasopharyngeal carcinoma’s early detection

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Science Bulletin 2024年第2期69卷 141-145页

作者： Xiao-Hui Zheng Allan Hildesheim wei-hua Jia State Key Laboratory of Oncology in South China Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060China Costa Rican Agency for Biomedical Investigation INCIENSA FoundationSan Jose 10108Costa Rica

Nasopharyngeal carcinoma(NPC),a highly invasive and metastatic cancer,is widely prevalent in South China,Southeast Asia,and North Africa.NPC patients with stages I and II are often asymptomatic.Therefore,NPC patients are usually diagnosed with advanced-stage(stages III and IV)at their first visit.Detection of NPC at early stage is the key to improve the survival of patients.Epstein-Barr virus(EBV)plays an essential role in NPC occurrence in endemic areas.EBV-based biomarkers,including EBV antibody in serum and EBV DNA in plasma,have been specifically proposed for NPC early detection.Herein,we summarize recent advances in biomarkers for the early detection of NPC.

关键词： patients nasopharyngeal Nasopharyngeal