检索结果-南通市图书馆

International Journal of Ophthalmology(English edition) 2014年第6期7卷 947-951页

作者： Na Li Xin-Guo Deng Shi-Hua Zhang Mei-Feng He dong-qing zhao State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen University Department of ophthalmology Huizhou First Hospital

AIM: To discuss the effects of different concentrations of tetramethylpyrazine(TMP), an active constituent of Chinese herb, on damaged Shandong human corneal epithelial cell(SDHCEC) induced by hydrogen peroxide.METHODS: We detected the combined effects of TMP with concentrations ranging from 4 mg/m L to 0.03 mg/m L and 800 μM hydrogen peroxide on SDHCEC. The methyl thiazolyl tetrazolium(MTT) assay was processed at 3, 6and 12 h separately while the detection of cell apoptosis at 6h only by flow cytometry.RESULTS: The viability of SDHCEC with 0.5 mg/m L,0.25 mg/m L, 0.125 mg/m L and 0.06 mg/m L TMP joint with800 μM hydrogen peroxide at 3h and 6h was significantly higher than that with 800 μM hydrogen peroxide only, P <0.05. However, except 0.25 mg/m L, TMP with other concentrations joint with 800 μM hydrogen peroxide at12 h could not significantly inhibit decreased SDHCEC viability induced by 800 μM hydrogen peroxide. At 12 h,TMP of 0.5 mg/m L, 0.25 mg/m L, 0.125 mg/m L and 0.06 mg/m L could significantly inhibit SDHCEC early apoptosis induced by 800 μM hydrogen peroxide, most remarkable at 0.25 mg/m L TMP, P <0.05.CONCLUSION: Our results suggested that hydrogen peroxide can induce apoptosis related damage to SDHCEC. TMP can protect SDHCEC from the damage,and the protective effects may be associated with its anti-apoptosis mechanism.

关键词： human corneal epithelial cell cell viability apoptosis hydrogen peroxide

Characteristics of AZ31 Mg alloy joint using automatic TIG welding

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2017年第1期24卷 102-108页

作者： Hong-tao Liu Ji-xue Zhou dong-qing zhao Yun-teng Liu Jian-hua Wu Yuan-sheng Yang Bai-chang Ma Hai-hua Zhuang Shandong Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteShandong Academy of SciencesJinan 250014China Shandong Engineering Research Center for Lightweight Automobiles Magnesium Alloys Advanced Materials InstituteShandong Academy of SciencesJinan 250014China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The automatic tungsten-inert gas welding（ATIGW） of AZ31 Mg alloys was performed using a six-axis robot. The evolution of the microstructure and texture of the AZ31 auto-welded joints was studied by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. The ATIGW process resulted in coarse recrystallized grains in the heat affected zone（HAZ） and epitaxial growth of columnar grains in the fusion zone（FZ）. Substantial changes of texture between the base material（BM） and the FZ were detected. The {0002} basal plane in the BM was largely parallel to the sheet rolling plane, whereas the c-axis of the crystal lattice in the FZ inclined approximately 25° with respect to the welding direction. The maximum pole density increased from 9.45 in the BM to 12.9 in the FZ. The microhardness distribution, tensile properties, and fracture features of the AZ31 auto-welded joints were also investigated.

关键词： magnesium alloys TIG welding microstructure texture microhardness

Leptotrichia hongkongensis sp.nov.,a novel Leptotrichia species with the oral cavity as its natural reservoir

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第6期11卷 391-401页

作者： Patrick C. Y. WOO Samson S. Y. WONG Jade L. L. TENG Kit-Wah LEUNG Antonio H. Y. NGAN dong-qing zhao Herman TSE Susanna K. P. LAU Kwok-Yung YUEN State Key Laboratory of Emerging Infectious Diseases The University of Hong Kong Hong Kong China Research Centre of Infection and Immunology The University of Hong Kong Hong Kong China Department of Microbiology The University of Hong Kong Hong Kong China Carol Yu Centre for Infection The University of Hong Kong Hong Kong China

A straight, non-sporulating, Gram-variable bacillus (HKU24T) was recovered from the blood culture of a patient with metastatic breast carcinoma. After repeated subculturing in BACTEC Plus Anaerobic/F blood culture broth, HKU24T grew on brucella agar as non-hemolytic, pinpoint colonies after 96 h of incubation at 37 °C in an anaerobic environment and aerobic environment with 5% CO2. Growth was enhanced with a streak of Staphylococcus aureus. HKU24T was non-motile and catalase-negative, but positive for alkaline phosphatase, β-glucosidase, and α-glucosidase. It hydrolyzed phenylphosphonate and reduced resazurin. 16S rRNA, groEL, gyrB, recA, and rpoB sequencing showed that HKU24T occupies a distinct phylogenetic position among the Leptotrichia species, being most closely related to Leptotrichia trevisanii. Using HKU24T groEL, gyrB, recA, and rpoB gene-specific primers, fragments of these genes were amplified from one of 20 oral specimens. Based on phenotypic and genotypic characteristics, we propose a new species, Leptotrichia hongkongensis sp. nov., to describe this bacterium.

关键词：关键词 Leptotrichia hongkongensis 细菌血文化厌氧的细菌新奇种类

Solid-state atomic hydrogen as a broad-spectrum RONS scavenger for accelerated diabetic wound healing

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第2期11卷 196-206页

作者： Man Luo Qin Wang Gang zhao Wei Jiang Cici Zeng qingao Zhang Ruyu Yang Wang dong Yunxi zhao Guozhen Zhang Jun Jiang Yucai Wang qing Zhu Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials Science University of Science and Technology of China Department of Radiology The First Affiliated Hospital of University of Science and Technology of China Division of Life Sciences and Medicine University of Science and Technology of China Shenzhen Senior High School Institute of Intelligent Innovation Henan Academy of Sciences

Hydrogen therapy shows great promise as a versatile treatment method for diseases associated with the overexpression of reactive oxygen and nitrogen species（RONS）. However, developing an advanced hydrogen therapy platform that integrates controllable hydrogen release, efficient RONS elimination, and biodegradability remains a giant technical challenge. In this study, we demonstrate for the first time that the tungsten bronze phase H0.53WO3（HWO） is an exceptionally ideal hydrogen carrier, with salient features including temperature-dependent highly-reductive atomic hydrogen release and broad-spectrum RONS scavenging capability distinct from that of molecular hydrogen. Moreover, its unique p H-responsive biodegradability ensures post-therapeutic clearance at pathological sites. Treatment with HWO of diabetic wounds in an animal model indicates that the solid-state atomic H promotes vascular formation by activating M2-type macrophage polarization and anti-inflammatory cytokine production, resulting in acceleration of chronic wound healing. Our findings significantly expand the basic categories of hydrogen therapeutic materials and pave the way for investigating more physical forms of hydrogen species as efficient RONS scavengers for clinical disease treatment.

关键词： atomic hydrogen RONS scavenger inflammatory regulation diabetic wound healing hydrogen therapy

H_∞ Output Feedback Control for Stochastic Systems with Mode-dependent Time-varying Delays and Markovian Jump Parameters

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2010年第4期7卷 447-454页

作者： Xu-dong zhao qing-Shuang Zeng Space Control and Inertial Technology Center Harbin Institute of Technology Harbin 150001 PRC

This paper deals with the H∞ control problems of Markovian jump systems with mode-dependent time delays. First, considering the mode-dependent time delays, a different delay-dependent H∞ performance condition for Markovian jump systems is proposed by constructing an improved Lyapunov-Krasovskii function. Based on this new H∞ disturbance attenuation criterion, a full-order dynamic output feedback controller that ensures the exponential mean-square stability and a prescribed H∞ performance level for the resulting closed-loop system is designed. Illustrative numerical examples are provided to demonstrate the effectiveness of the proposed approach.

关键词： H∞ performance Markovian jump systems time-varying delay output feedback control linear matrix inequality （LMI）

Delay-dependent Stability Analysis for Markovian Jump Systems with Interval Time-varying-delays

在线全文

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2010年第2期7卷 224-229页

作者： Xu-dong zhao qing-Shuang Zeng Space Control and Inertial Technology Center Harbin Institute of Technology Harbin 150001 PRC

This paper proposes improved stochastic stability conditions for Markovian jump systems with interval time-varying delays. In terms of linear matrix inequalities （LMIs）, less conservative delay-range-dependent stability conditions for Markovian jump systems are proposed by constructing a different Lyapunov-Krasovskii function. The resulting criteria have advantages over some previous ones in that they involve fewer matrix variables but have less conservatism. Numerical examples are provided to demonstrate the efficiency and reduced conservatism of the results in this paper.

关键词： Stochastic stability Markovian jump systems linear matrix inequality （LMI）.

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： Si-Na Wei zhao-qing Feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field

Exceptional points enhance sensing in silicon micromechanical resonators

在线全文

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2024年第1期10卷 17-25页

作者： Man-Na Zhang Lei dong Li-Feng Wang qing-An Huang Key Laboratory of MEMS of the Ministry of Education Southeast UniversityNanjing 210096China

Exceptional points(EPs)have recently emerged as a new method for engineering the response of open physical systems,that is,systems that interact with the environment.The systems at the EPs exhibit a strong response to a small perturbation.Here,we show a method by which the sensitivity of silicon resonant sensors can be enhanced when operated at EPs.In our experiments,we use a pair of mechanically coupled silicon micromechanical resonators constituting a parity-time(PT)-symmetric dimer.Small perturbations introduced on the mechanically coupled spring cause the frequency to split from the EPs into the PT-symmetric regime without broadening the two spectrum linewidths,and this frequency splitting scales with the square root of the perturbation strength.The overall signal-tonoise ratio is still greatly enhanced,although the measured noise spectral density of the EP sensing scheme has a slight increase comparable to the traditional counterpart.Our results pave the way for resonant sensors with ultrahigh sensitivity.

关键词： resonant symmetric points

Current understanding of ELF4 deficiency:a novel inborn error of immunity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Pediatrics 2024年第5期20卷 444-450页

作者： Hong-Qiang Du Xiao-dong zhao Department of Rheumatology&Immunology National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of Child Rare Diseases in Infection and ImmunityChildren’s Hospital of Chongqing Medical UniversityZhongshan Er Road 136Yuzhong DistrictChongqingChina

Background ELF4 deficiency has been recently recognized as a novel disorder within the spectrum of inborn errors of immunity(IEIs),specifically categorized as a“disease of immune dysregulation.”Cases of this condition,reported by our team and others,are very limited worldwide.As such,our current knowledge of this new disease remains preliminary.This review aims to provide a brief overview of the clinical manifestations,pathogenesis,and treatment strategies for this novel IEI.Data sources A comprehensive review was conducted after an extensive literature search in the PubMed/Medline database and websites concerning transcriptional factor ELF4 and reports concerning patients with ELF4 deficiency.Our search strategy was“ELF4 OR ETS-related transcription factor Elf-4 OR EL4-like factor 4 OR myeloid Elf-1-like factor”as of the time of manuscript submission.Results The current signature manifestations of ELF4 deficiency disorder are recurrent and prolonged oral ulcer,abdominal pain,and diarrhea in pediatric males.In some cases,immunodeficiency and autoimmunity can also be prominent.Targeted Sanger sequencing or whole exome sequencing can be used to detect variation in ELF4 gene.Western blotting for ELF4 expression of the patient’s cells can confirm the pathogenic effect of the variant.To fully confirm the pathogenicity of the variant,further functional test is strongly advised.Glucocorticoid and biologics are the mainstream management of ELF4 deficiency disorder.Conclusions Pediatric males presenting with recurring ulcerations in digestive tract epithelium with or without recurrent fever should be suspected of DEX.When atypical presentations are prominent,variations in ELF4 gene should be carefully evaluated functionally due to the complex nature of ELF4 function.Experience of treating DEX includes use of glucocorticoid and biologics and more precise treatment needs more patients to identify and further mechanistic study.

关键词： ELF4 transcription factor Immune dysregulation Inborn errors of immunity Mechanism Recurrent infections

Improvement of impact properties of Al-Si-Mg alloy via solution treatment and joint modification with Sr and La

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第7期43卷 3301-3313页

作者： Xiong-Ling Zheng Shao-Xiang Li Jia-Le Ma qing-Yan Xu Hai-dong zhao Zhi-Qiang Han Key Laboratory for Advanced Materials Processing Technology Ministry of EducationSchool of Materials Science and EngineeringTsinghua University National Engineering Research Center of Near-Net Shape Forming for Metallic Materials South China University of Technology

An effort to obtain superior impact properties for Al-7Si-0.35 Mg alloy is presented,where modification with 0.02 wt% Sr and 0.1 wt% La as well as solution treatment was jointly employed.The samples were solution treated at 535℃ for 15 min to 12 h.The microstructure,fracture mechanism,and their correlation with the impact properties of the alloy were studied in detail mainly through optical microscopy（OM）,scanning electron microscopy（SEM） and oscillography impact test.The results show that the addition of Sr and La refined the eutectic Si particles significantly from～ 2.05 μm（modified with Sr alone） to～ 0.75 μm in as-cast microstructure,leading to a very homogeneous distribution of spheroidized Si particles in the alloy solution treated at 535℃ for 8 h.The alloy exhibits excellent impact toughness up to 75 J·cm-2,which is much higher than the maximum impact toughness of the alloys modified by Sr alone(～ 46 J·cm-2).The major reason for this remarkable increase in the impact property is the dramatic increase in crack initiation energy.The dispersoid-free zones（DFZs）near the eutectic regions mainly consist of the ductile Al-matrix,which exhibits excellent ductility.The ductile Al-matrix of the DFZs hinders the crack propagation,resulting in a significant increase in crack propagation energy.

关键词： Aluminum alloys Modification Solution treatment Microstructure Impact properties Fracture mechanism