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Chinese Journal of Astronomy and Astrophysics 2002年第3期2卷 207-215页

作者： Lin-Peng Cheng , jian-Yan wei and yong-Heng ZhaoNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We examined the correlation between the ROSAT Hardness Ratio 1 and Count Rates eight Narrow-line Seyfert 1 Galaxies (NLSls) and 14 Broad-line Seyfertl Galaxies (BLSls). We found that six of the NLSls show a positive HR1-CTs correlation, and seven of the BLSls, a negative correlation. The other two NLSls and seven BLSls do not show any clear HR1-CTs correlation. Thus, the spectral behavior is statistically different for the NLSls and BLSls. The different behaviors can possibly be interpreted in terms of a stable 'soft excess' that is strong in NLSls and weak in BLSls, plus a power law component, common to both, which softens with increasing flux.

关键词： galaxies: Seyfert - galaxies: active - X-ray: galaxies

Water-induced MAPbBr_(3)@PbBr(OH) with enhanced luminescence and stability

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Light(Science & Applications) 2020年第1期9卷 1598-1608页

作者： Kai-Kai Liu Qian Liu Dong-Wen Yang Ya-Chuan Liang Lai-Zhi Sui jian-yong wei Guo-wei Xue Wen-Bo Zhao Xue-Ying Wu Lin Dong Chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian 116023China

Poor stability has long been one of the key issues that hinder the practical applications of lead-based halide *** this paper,the photoluminescence(PL)quantum yield(QY)of bromide-based perovskites can be increased from 2.5% to 71.54% by introducing water,and the PL QY of a sample in aqueous solution decreases minimally over 1 *** enhanced stability and PL QY can be attributed to the water-induced methylamino lead bromide perovskite(MAPbBr_(3))@PbBr(OH).We note that this strategy is universal to MAPbBr_(3),formamidine lead bromide perovskite(FAPbBr_(3)),inorganic lead bromide perovskite(CsPbBr_(3)),***-emitting devices(LEDs)are fabricated by using the as-prepared perovskite as phosphors on a 365 nm UV *** luminance intensity of the LED is 9549 cd/m^(2) when the driven current is 200 mA,and blemishes on the surface of glass are clearly observed under the illumination of the *** work provides a new strategy for highly stable and efficient perovskites.

关键词： perovskite stability luminescence

Genetic alterations and expression of inhibitor of growth 1 in human sporadic colorectal cancer

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World Journal of Gastroenterology 2005年第39期11卷 6120-6124页

作者： Li-Sheng Chen jian-Bao wei yong-Chun Zhou Sen Zhang Jun-Lin Liang Yun-Fei Cao Zong-jiang Tang Xiao-Long Zhang Feng Gao Department of Coloproctological Surgery the First Affiliated Hospital Guangxi Medical University Nanning 530021 Guangxi Province China

AIM： To explore the effect and significance of inhibitor of growth 1 （ING1） gene in carcinogenesis and progression of human sporadic colorectal cancer. METHODS： mRNA expression, mutation, and loss of heterozygosity （LOH） of ING1 gene in 35 specimens of sporadic colorectal cancer tissues and the matched normal mucous membrane tissues were detected by semi-quantitative reverse transcriptase-polymerase chain reaction （RT-PCR）, PCR-single strain conformation polymorphism （PCR-SSCP） and PCR-simple sequence length polymorphism （PCR-SSLP） using microsatellite markers, respectively. RESULTS： The average ratios of light intensities of p33^ING1b and p47^ING1a mRNA expression in the cancerous tissues were significantly lower than those in normal tissues. The difference between the two mRNA splices was not significant in the matched tissues. In addition, the ratios of light intensities of p33^ING1b and p47^ING1a mRNA expression in the cancerous tissues of Dukes＇ stages C and D were significantly lower than those in cancerous tissues of Dukes＇ stages A and B. However, no mutation of ING1 gene was detected in all 35 cases; only 4 cases of LOH （11.4%） were found. CONCLUSION： p33^ING1b and p47^ING1a mRNA expressions are closely related with the carcinogenesis and progression of human sporadic colorectal cancer. No mutation of ING1 gene is found, and there are only few LOH in sporadic colorectal cancers. These might not be the main reasons for the down regulation of ING1 expression. Its low expression may happen in transcription or post-transcription.

关键词： Colorectal cancer Inhibitor of growth 1(ING1) Expression Mutation Loss of heterozygosity

Solar cycles during the seventeenth century revealed by equatorial aurora records

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Earth and Planetary Physics 2025年第1期9卷 182-187页

作者： yong wei LiMei Yan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system *** the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity *** study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to ***,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that *** research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses.

关键词： solar cycle Maunder Minimum solar activity red equatorial aurora West Pacific geomagnetic anomaly

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： wei-Lei Zhou Siwei Wang yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

关键词：

Role of extracellular signal-regulated kinase in regulating expression of interleukin 13 in lymphocytes from an asthmatic rat model

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Chinese Medical Journal 2010年第13期123卷 1715-1719页

作者： LI Yuan-yuan LIU Xian-sheng LIU Chang XU yong-jian XIONG wei-ning Department of Respiratory Medicine Tongji Hospital Tongii Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Background The extracellular signal-regulated kinase （ERK） is widely expressed in mammal cells and involved in airway proliferation and remodeling in asthma. In this study, we intend to explore the role of ERK in the expression of the Th2 cytokine, interleukin 13 （IL-13） in lymphocytes in asthma. Methods Forty Sprague-Dawley rats were randomly divided into two groups： normal control and asthmatic groups. Peripheral blood lymphocytes were isolated and purified from the blood of each rat and divided into five groups： control, asthmatic lymphocytes, asthmatic cells stimulated with ERK activator epidermal growth factor （EGF）, or with ERK inhibitor PD98059, or with EGF and PD98059 together. The expression of phosphorylated-ERK （p-ERK） was observed by immunocytochemical staining, the expression of ERK mRNA was determined by reverse transcriptase-PCR, IL-13 protein in supernatants was measured by ELISA. Results （1） The ERK mRNA level and the percentage of cells with p-ERK in lymphocytes from asthmatic rats were significantly higher than those in normal controls, and were significantly increased by EGF administration. This effect of EGF was significantly inhibited by PD98059 pretreatment. （2） IL-13 protein in supernatants of asthmatic lymphocytes was higher than that produced by normal control lymphocytes, and was significantly increased by EGF treatment. This EGF effect was partly blocked by PD98059 pretreatment. （3） There was a significant positive correlation between the percentage of cells with p-ERK in peripheral blood lymphocytes and IL-13 protein in supernatants of lymphocytes from asthmatic rats. Conclusions In asthma the ERK expression and activation levels were increased, as was the protein level of IL-13. The ERK signaling pathway may be involved in the increased expression of the Th2 cytokine IL-13 in asthma.

关键词： asthma interleukin 13 lymphocytes extraceUular signal-regulated MAP kinases

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping CHENG jian wei Chao YUAN Bin YU Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

Formative mechanism of intracanal fracture fragments in thoracolumbar burst fractures： a finite element study

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Chinese Medical Journal 2013年第15期126卷 2852-2858页

作者： ZENG Zhi-li ZHU Rui LI Shan-zhu YU Yan WANG jian-jie JIA yong-wei CHEN Bo CHENG Li-ming Tongji Univ Sch Med Tongji Hosp Dept Spine Surg Shanghai 200065 Peoples R China Tongji Univ Sch Life Sci & Technol Shanghai 200092 Peoples R China

Background Thoracolumbar burst fracture is a common clinical injury, and the fracture mechanism is still controversial. The aim of this research was to study the formation of intracanal fracture fragments in thoracolumbar burst fractures and to provide information for the prevention of thoracolumbar bursts fractures and reduction of damage to the nervous system. Methods A nonlinear three-dimensional finite element model of T11-L3 segments was established, and the injury processes of thoracolumbar bursts were simulated. The intact finite element model and the finite element model after the superior articular were impacted by 100 J of energy in different directions. The distribution and variation of stress in the superior posterior region of the L1 vertebral body were analyzed. Abaqus 6.9 explicit dynamic solver was used as finite element software in calculations. Results A three-dimensional nonlinear finite element model of the thoracolumbar spine was created. In the intact model, stress was concentrated in the superior posterior region of the L1 vertebral body. The stress peak was a maximum for the extension impact load and a minimum for the flexion impact load. The stress peak and contact force in the facet joint had close correlation with time. The stress peak disappeared after excision of the superior articular process. Conclusions The three-dimensional nonlinear finite element model was suitable for dynamic analysis. The contact force in the facet joint, which can be transferred to the superior posterior vertebral body, may explain the spinal canal fragment in thoracolumbar burst fractures.

关键词： thoracolumbar vertebra burst fracture finite element model injury

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei Huijie Zhang jian Yang Jia Ran Jiqiang Ning Haiyan Wang yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of Chemistry Zhejiang Normal University Jinhua Advanced Research Institute Department of Optical Science and Engineering Fudan University College of Chemistry and Materials Engineering Zhejiang A&F University

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF) has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA), but there still remain problems such as limited yield, short cycle life,and ambiguous reaction mechanism. Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF, a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking. We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA, particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts, including heterointerface construction, defect engineering,single-atom engineering, and in situ reconstruction. Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated, and challenges and future directions of electrochemical oxidation of HMF are also prospected. This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Structural design

Security of a Novel Antitapeworm Drug:Arecoline Hydrobromide

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Animal Husbandry and Feed Science 2010年第2期2卷 26-28,31页

作者： ZHOU Xu-zheng ZHANG Ji-yu LI Jin-shan LI jian-yong wei Xiao-juan NIU jian-rong LI Bing Key Laboratory of New Animal Medicine Project Lanzhou Institute of Animal Husbandry and Veterinary Medicine Chinese Academy of Agricul-tural Sciences Lanzhou 730050 China

[Objective] To make an objective evaluation about security of a new veterinary drug-arecoline hydrobromide according to the research results and papers in recent years and supply science basis for clinical usage. [ Method] The security of arecoline hydrobromide was evaluated based on acute toxicity tests; the ranges of safe medication, tolerability and toxicity as well as ＂Three-induced＇ effects （carcinogensis, mutagene- sis and teratogenesis） and reproductive toxicity were summarized according to the combinations of experimental results, papers and clinical effects. E Result] The results of acute toxicity tests in mice and rats showed that LD^0 （50% lethal dosages） of arecoline hydrobromide in mice was 691.83 mg/（***） and 95% incredible range of its LDso was 642.92 -744.47 mg/（ kg. BW）, and LDso of arecoline hydrobromide in rats was 2 054 mg/（***） and 95% incredible range of its LDso was 1 908 -2 210 mg/（***）. Its LDso value was hundreds times higher than the recommen- ded clinical dosage [ 1 -5 mg/（kg-BW） ], therefore it is safe to apply in clinic. The research results of ranges of safe medication, tolerability and toxicity showed that arecoline hydrobromide could entirely dispel the dog Diphyllobothrium, Spirometra mansoni, Dipylidium mesocestoides, Linea- tus and Cysticercus at dosages of 2 -3 mg/（ ***）, and the same effects to Railletina tapeworm of chickens and Drepanidotaenia lanceolata of duck and goose at dosages of I -2 mg/（***）. The arecoline hydrobromide had muscarinic effects as side-effects and could cause vomiting, di- arrhea and other clinical symptoms to discharge the paralyzed worm from livestock body rapidly and completely. The arecoline hydrobromide had ＂Three-induced＂ effects and reproductive toxicity when it was used as antitapeworm drug with long-term, sustained and a large number of drug us- age, rather than used in clinical application with shorter time and lower dosage of administration. [ Conclusion] The arecoline hydrobromide is

关键词： Arecoline hydrobromide Acute toxicity "Three-induced" effects Reproductive toxicity