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Comparing the Genotype and Drug Susceptibilities between Mycobacterium avium and Mycobacterium intracellulare in China

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Biomedical and Environmental Sciences 2017年第7期30卷 517-525页

作者： ZHENG hui Wen PANG Yu HE Guang Xue song Yuan Yuan zhao Yan Lin National institute for communicable disease control and prevention Chinese center for disease control and prevention Beijing 102206 China National Tuberculosis Reference Laboratory Chinese Center for Disease Control and Prevention Beijing 102206 China Science and Technology Department Chinese Center for Disease Control and Prevention Beijing 102206 China

Objective Mycobacterium avium （M. avium） and Mycobacterium intracellulare （M. intracellulare） are the major causative agents of nontuberculous mycobacteria （NTM）-related pulmonary infections. However, little is known about the differences in drug susceptibility profiles between these two species. Methods A total of 393 NTM isolates were collected from Shanghai Pulmonary Disease Hospital. Sequencing of partial genes was performed to identify the strains at species level. The minimum inhibitory concentration （MIC） was used to evaluate the drug susceptibility against 20 antimicrobial agents. Variable number of tandem repeat （VNTR） typing was conducted to genotype these two species. Results A total of 173 （44.0%） M. avium complex （MAC） isolates were identified, including 41 （10.4%） M. avium isolates and 132 （33.6%） M. intracellulare isolates. Clarithromycin and amikacin were the two most effective agents against MAC isolates. The Hunter-Gaston Discriminatory Index （HGDI） values for VNTR typing of M. avium and M. intracellulare isolates were 0.993 and 0.995, respectively. Levofloxacin resistance was more common among the unclustered strains than among the clustered strains of M. intracellulare. Conclusion M. intrecellulare was the most common NTM species in China. Clarithromycin and amikacin had high antimicrobial activities against MAC. VNTR typing of MAC isolates revealed a high discriminatory power. Levofloxacin resistance was associated with unclustered strains of M. intracellulare.

关键词： Nontuberculous mycobacterium, Phenotype Genotype Susceptibility Resistance

Impact of Financial Technology on Regional Green Finance

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Computer Systems Science & Engineering 2021年第12期39卷 391-401页

作者： Zheng Liu Juanjuan song hui Wu Xiaomin Gu Yuanjun zhao Xiaoguang Yue Lihua Shi School of Management Shanghai University of Engineering ScienceShanghai201620China School of Financial Technology Shanghai Lixin University of Accounting and FinanceShanghai201209China School of Business Administration Shanghai Lixin University of Accounting and FinanceShanghai201209China School of Sciences European University CyprusNicosia22006Cyprus

Finance is the core of modern economy,and a strong country cannot do without the support of financial *** the rapid development of economy and society,the traditional financial services can not support the increasingly large and complex economic *** a brand-new format,financial technology can help the financial industry to restructure and *** the same time,as an international consensus,green development is the only way for China to achieve sustainable ***,it is of great practical significance to study the impact of finance on the regional development of green *** on the essence of green finance development,fuzzy principal component analysis is used to build the green finance evaluation index system in this *** the data of three provinces and cities in the Yangtze River Delta from 2015 to 2019 as an example,QAP analysis is used to study the impact of financial tech-nology on the regional development of green *** shows that expla-natory variables are highly significant,that is,financial technology has a significant role in promoting green ***,based on the research conclu-sions,this paper puts forward suggestions on how green technology can better promote the development of green finance from three aspects of top-level design,technical research and supervision.

关键词： Regional green finance financial technology fuzzy principal component analysis QAP analysis

Control of Equiaxed Crystal Ratio of High Carbon Steel Billets by Circular Seam Cooling Nozzle

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Journal of Iron and Steel Research International 2011年第2期18卷 24-30页

作者： LI Pei-song LU Jun-hui QIU Sheng-tao WANG Zhong-ying zhao Pei Northeastern University Shenyang 110004 Liaoning China State Key Laboratory of Advanced Steel Processing and Products Central Iron and Steel Research Institute Beijing 100081 China

A circular seam cooling nozzle and its online control system have been developed to reduce the center segregation in high carbon steel billets by decreasing the superheat of the molten steel and improving the equiaxed crystal ratio based on the numerical results. An industrial experiment has been carried out on a 150 mm× 150 mm caster to investigate the effect of the circular seam cooling nozzle on the superheat removal of the molten steel. The results show that the circular seam cooling nozzle can be used to control the casting temperature in a closed loop control system. The online control system can be effectively adapted to the variation of operating parameters. The casting lasts about 4 h and about 400 t steel is successfully produced in a continuous operation. The removal of about 14 ℃ superheat and the improvement of approximate 10% equiaxed crystal ratio can be achieved by the newly developed circular seam cooling nozzle.

关键词： circular seam cooling nozzle high equiaxed crystal ratio billet low superheat

Observed Long-and Short-lived North Atlantic Oscillation Events:Role of the Stratosphere

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Advances in Atmospheric Sciences 2020年第12期37卷 1338-1358页

作者： Jie song Jingjing zhao State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Utilizing three different sets of reanalysis data,this study examines the long-and short-lived observed positive North Atlantic Oscillation(NAO)events(referred to as NAO+_LE and NAO+_SE)and long-and short-lived observed negative NAO events(referred to as NAO−_LE and NAO−_SE).Composite results indicate that the NAO-like circulation anomalies associated with the long-lived NAO events can reach the stratosphere,while they are primarily confined to the troposphere in the short-lived NAO ***,the coupling/connection of stratospheric and tropospheric circulation anomalies is much better(worse)in the long-lived(short-lived)NAO events.A series of modified stratospheric initial-value experiments conducted with a simplified model indicate that a better(worse)connection between stratospheric and tropospheric circulation anomalies in the initial-value fields tend to gradually induce the NAO-like tropospheric circulation anomalies in the troposphere on the subsequent days,and thus naturally elongate(reduce)the lifetimes of the original NAO events by altering the tropospheric synoptic eddy vorticity flux over the North Atlantic region.

关键词： North Atlantic Oscillation lifetimes stratosphere eddy forcing

Syntheses, Crystal Structures, and Biological Activities of Two Enantiomeric 2-Trifluoromethylthieno[2,3-d]pyrimidin-4-amine Derivatives

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1224-1230页

作者： GAO hui FU Ju zhao Ming-Juan song Xin-Jian YANG Ping ZHENG Yin Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities School of Chemical and Environmental Engineering Hubei University for Nationalities

Two enantiomeric 2-trifluoromethyl-6,7-dihydro-5H-cyclopenta[4,5]thieno[2,3-d] pyrimidin-4-amine derivatives were synthesized by nucleophilic substitution of two chiral amines with 4-chloro-2-trifiuoromethyl-6,7-dihydro-5H-cyclopenta[4~5]thieno[2-3-d]pyrimidine, which started from 2-amino-5,6-dihydro-4H-cyclopenta[b]thiophene-3-carbonitrile, trifluoroacetic acid （TFA） and phosphoryl trichloride via one-pot procedure. Their structures were determined by single-crystal X-ray diffraction. Enantiomer （R）-3,（R）-N-（1-phenylethyl）-2-trifluoromethyl-6,7- dihydro-5H-cyclopenta[4,5]thieno[2,3-d]pyrimidin-4-amine crystallizes in the tetragonal system, space group P43 with a = 8.6847（6）, b = 8.6847（6）, c = 22.419（2） A, V= 1690.9（3） A3, Z = 4, Dc = 1.428 g/cm^3, p = 0.228 mm-1, F（000） = 752, the final R = 0.0463 and wR = 0.1257 for 3442 observed reflections with 1〉 20（/）. Enantiomer （S）-3,（S）-N-（1-phenylethyl）-2-trifluoromethyl-6,7-dihydro- 5H-cycloperita[4,5]thieno[2,3-d]pyrimidin-4-amine crystallizes in the tetragonal system, space group P41 with a = 8.688, b = 8.688, c = 22.421 A, V = 1692.4 A3, Z = 4, Dc = 1.426 g/cm^3, μ= 0.227 mm^-1, F（000） = 752, the final R = 0.0682 and wR = 0.1806 for 3182 observed reflections with ≥20（I）. The preliminary bioassay indicated that the R-enantiomer exhibits higher antitumor activity against MCF-7 than gefitinib.

关键词： thieno[2,3-d]pyrimidine, enantiomeric pair, trifluoromethyl, antitumor activity

Cr Stable Isotope Fractionation in Arbuscular Mycorrhizal Dandelion and Cr Uptake by Extraradical Mycelium

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Pedosphere 2015年第2期25卷 186-191页

作者： REN Bai-hui WU song-Lin CHEN Bao-Dong WU zhao-Xiang ZHANG Xin State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

As common soil fungi that form symbioses with most terrestrial plants,arbuscular mycorrhizal(AM) fungi play an important role in plant adaptation to chromium(Cr) ***,little information is available on the underlying mechanisms of AM symbiosis on plant Cr *** this study,dandelion(Taraxacum platypecidum Diels.) was grown with and without inoculation of the AM fungus Rhizophagus irregularis and Cr uptake by extraradical mycelium(ERM) was investigated by a compartmented cultivation system using a Cr stable isotope *** results indicated that AM symbiosis increased plant dry weights and P concentrations but decreased shoot Cr *** the Cr stable isotope tracer technology,the work provided possible evidences of Cr uptake and transport by ERM,and confirmed the enhancement of root Cr stabilization by AM *** study also indicated an enrichment of lighter Cr isotopes in shoots during Cr translocation from roots to shoots in mycorrhizal plants.

关键词： arbuscular mycorrhizal fungi Cr contamination Cr translocation hyphae mycorrhizal plant

An application of matching pursuit time-frequency decomposition method using multi-wavelet dictionaries

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Petroleum Science 2012年第3期9卷 310-316页

作者： zhao Tianzi song Wei Library of China University of Petroleum Beijing 102249China CNPC Key Laboratory of Geophysical Exploration China University of PetroleumBeijing 102249China

In the time-frequency analysis of seismic signals, the matching pursuit algorithm is an effective tool for non-stationary signals, and has high time-frequency resolution and a transient structure with local self-adaption. We expand the time-frequency dictionary library with Ricker, Morlet, and mixed phase seismic wavelets, to make the method more suitable for seismic signal time-frequency decomposition. In this paper, we demonstrated the algorithm theory using synthetic seismic data, and tested the method using synthetic data with 25% noise. We compared the matching pursuit results of the time-frequency dictionaries. The results indicated that the dictionary which matched the signal characteristics better would obtain better results, and can reflect the information of seismic data effectively.

关键词： Matching pursuit seismic attenuation wavelet transform Wigner Ville distribution time- frequency dictionary

Investigation of the effect of filling level on the wear and vibration of a SAG mill by DEM

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Particuology 2022年第4期20卷 24-34页

作者： Changhua Xie Yuan zhao Tao song Yongzhi zhao Institute of Process Equipment Zhejiang UniversityHangzhou 310027China State Key Laboratory of Process Automation in Mining & Metallurgy.Beijing 100160 China Beijing Key Laboratory of Process Automation in Mining & Metallurgy Beijing 100160China

Semi-autogenous grinding(SAG)mill is widely used in the grinding process of coal and ores because of its strong applicability,large capacity and low consumption of grinding ***,the research of SAG mill is still of great important practical *** those parameters of the SAG mill,the flling level is very important for it is not only directly related to the processing capacity of the mill,but also affects the operation cost and stability of *** this paper,combined with shear impact energy model(SIEM)and discrete element method(DEM),the particle collision energy spectrum was applied to analyze the influence of ore flling level and media flling level on the power draw of the mill,the impact energy on ore,and the wear of liner and media in a slice of an industrial SAG *** was found that increasing the ore flling level would increase energy consumption and reduce the energy efficiency and the wear of liner and grinding ***,the vibration of mill was explored from the collision energy on *** results showed that the low frequency but high energy ollision between grinding media and liner was the main reason for liner wear and mill vibration.

关键词： Flling level SAG mill Collision energy DEM Wear Vibration

Stochastic Stability of Discrete Time Positive Markov Jump Nonlinear Systems

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Journal of Systems Science & Complexity 2023年第5期36卷 1949-1960页

作者： zhao Ping zhao Yan song Xinmin NIU Ben School of Information Science and Engineering Shandong Normal UniversityJinan 250358China School of Mathematical Sciences University of JinanJinan 250022China

This paper investigates the stochastic stability of discrete time positive Markov jump nonlinear systems(PMJNS).Some definitions on stochastic stability for discrete time PMJNS are introduced ***,using the multiply max-separable Lyapunov function method,some stochastic stability criterions of discrete time PMJNS are provided,and some corresponding criterions are also provided for discrete time positive Markov jump linear systems(PMJLS).Different from previous conclusions that require subsystems to be stable or marginally stable,the obtained results allow some subsystems to be *** on the proposed criterions,the stochastic stability behavior of discrete time positive Markov jump systems can be obtained just from the algebraic properties of the system function and the probability characteristics of the Markov *** illustrate the main results,two simulation examples are provided at the end.

关键词： Markov jump system nonlinear system positive system stochastic stability