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Relationship between the high frequency of 23S rRNA point mutations in Treponema pallidum and low serological response rate to azithromycin treatment in China

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International Journal of Dermatology and Venereology 2019年第1期2卷 6-14页

作者： Rui-li Zhang Qian-Qiu Wang Zhi-Ju Zheng Guo-Jun liang li-Jia yang li-gang yang Dong-Nu Pei Shao-Chun lin Department of Dermatology Affiliated Wuxi No.2 People's Hospital of Nanjing Medical UniversityWuxiJiangsu 214002China National Center for STD Control and Prevention China Centers for Diseases Control and PreventionHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China Department of Dermatology Dermatology Hospital of Southern Medical UniversityGuangzhouGuangdong 510091China Department of Dermatology Hainan Provincial Dermatology HospitalHaikouHainan 570100China Department of Dermatology Institute of DermatologySichuan Provincial People's HospitalChengduSichuan 611500China

Objective Although azithromycin is effective against Treponema pallidum (T.pallidum),the causative agent of syphilis,recent reports indicate that the prevalence of azithromycin resistance in China is very high,which may result in the failure of treatment.In this study,we aimed to investigate the association between azithromycin resistance and therapeutic outcomes in early syphilis patients.Methods Between February 2010 and December 2014,patients aged 18-65 years with early syphilis were enrolled.T.pallidum DNA were extracted to test the presence of A2058G and A2059G mutations.Then,eligible patients were randomly assigned to receive oral azithromycin (0.5 g,once daily for 15 days) or intramuscular BPG (2.4 million units,once weekly for 3 weeks).All patients were followed up in 2 weeks and 3,6,9,and 12 months after treatment to collect demographic and clinical characteristics and laboratory results.The differences on serological response,serological failure and serofast rate were compared between the two groups by Chi-square test.Results Among the 187 T.pallidum-infected patients enrolled,172 (92.0%) cases had a mutation associated with azithromycin resistance (A2058G,153 cases;A2059G,19 cases).During the 5-year study period,the percentage of cases enrolled with these mutations steadily increased,from 90.9% in 2010 to 95.3% in 2014.Of the 172 patients presenting with these mutations,only 78 (45.3%;all benzathine penicillin G [BPG]-treated) obtained a serological response to treatment;32.6% and 22.1% of patients presented with serological failure and serofast results,respectively.For azithromycin-treated cases,66.3% and 33.7% had serological failure and serofast results,respectively,in contrast with 1.1% and 11.3% of BPG-treated cases.However,among the A2058G-and A2059G-negative patients,the serological response rates between the two treatment groups were similar.In multivariate analyses,patients with lower rapid plasma reagin (RPR) titers (RPR,≤ 1 ∶ 8;odds ratio [OR],0.23;95% confidence interval [CI],0.09-0.37) or

关键词： Syphilis Azithromycin Mutation Serological response Treponema pallidum

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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu yang li Yu liu Xiao-Xiao ling li-Guang Wu li yang Lan yang Bo yang Yong-gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

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A Correlation-Based Stochastic Model for Massive MIMO Channel

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China Communications 2024年第1期21卷 175-187页

作者： yang liu gang li Chengxiang Wang National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast UniversityNanjing 211189China School of Internet of Things Engineering Jiangnan UniversityWuxi 214122China Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China

In this paper,the channel impulse response matrix(CIRM)can be expressed as a sum of couplings between the steering vectors at the base station(BS)and the eigenbases at the mobile station(MS).Nakagami distribution was used to describe the fading of the coupling between the steering vectors and the eigenbases.Extensive measurements were carried out to evaluate the performance of this proposed model.Furthermore,the physical implications of this model were illustrated and the capacities are analyzed.In addition,the azimuthal power spectrum(APS)of several models was analyzed.Finally,the channel hardening effect was simulated and discussed.Results showed that the proposed model provides a better fit to the measured results than the other CBSM,i.e.,Weichselberger model.Moreover,the proposed model can provide better tradeoff between accuracy and complexity in channel synthesis.This CIRM model can be used for massive MIMO design in the future communication system design.

关键词： CBSM channel capacity channel hardening channel modeling massive MIMO

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Photoacoustic elastography based on laser-excited shear wave

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 56-72页

作者： yang liu Ruoyi Shi gang li Mingjian Sun School of Astronautics Harbin Institute of TechnologyHarbin 150000P.R.China School of Information Science and Engineering Harbin Institute of TechnologyWeihai 264200P.R.China

Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of tissues.In this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound imaging.By using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be realized.The laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear wave.The frequency of shear wave induced by laser is higher and the frequency band is wider.By tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of tissue.The feasibility of the method is verified by experiments.Compared with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the phantoms.In addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is higher.Compared to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity.

关键词： Elastography shear wave photoacoustic Young's modulus

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Maslinic acid supplementation prevents di(2-ethylhexyl)phthalate-induced apoptosis via PRDX6 in peritubular myoid cells of Chinese forest musk deer

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Journal of Environmental Sciences 2024年第9期143卷 47-59页

作者： Heran Cao Zhenpeng li Tianqi Jin Shuyang He Shujuan liu Long li yang Wang Ye Gong gang Wang Fangxia yang Wuzi Dong College of Animal Science and Technology Northwest A&F UniversityShaanxi 712100China College of Forestry Northwest A&F UniversityShaanxi 712100China Biology Research Centre of Qin-Mountains Wildlife Northwest A&F UniversityShaanxi 712100China Shaanxi Qiyuan-Times Agri-Tech Development Co.Ltd. Shaanxi 725000China

Chinese forest musk deer(FMD),an endangered species,have exhibited low reproductive rates even in captivity due to stress conditions.Investigation revealed the presence of di(2-ethylhexyl)phthalate(DEHP),an environmental endocrine disruptor,in the serum and skin of captive FMDs.Feeding FMDs with maslinic acid(MA)has been observed to alleviate the stress response and improve reproductive rates,although the precise molecular mechanisms remain unclear.Therefore,this study aims to investigate the molecular mechanisms underlying the alleviation of DEHP-induced oxidative stress and cell apoptosis in primary peritubular myoid cells(PMCs)through MA intake.Primary PMCs were isolated and exposed to DEHP in vitro.The results demonstrated that DEHP significantly suppressed antioxidant levels and promoted cell apoptosis in primary PMCs.Moreover,interfering with the expression of PRDX6 was found to induce excessive reactive oxygen species(ROS)production and cell apoptosis in primary PMCs.Supplementation with MA significantly upregulated the expression of PRDX6,thereby attenuating DEHP-induced oxidative stress and cell apoptosis in primary PMCs.These findings provide a theoretical foundation for mitigating stress levels and enhancing reproductive capacity of in captive FMDs.

关键词： Maslinic acid Forest musk deer Di(2-ethylhexyl)phthalate Peritubular myoid cells PRDX6

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Automation and Orchestration of Zero Trust Architecture:Potential Solutions and Challenges

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Machine Intelligence Research 2024年第2期21卷 294-317页

作者： yang Cao Shiva Raj Pokhrel Ye Zhu Robin Doss gang li Centre for Cyber Resilience and Trust Deakin UniversityBurwood 3125Australia School of Information Technology Deakin UniversityGeelong 3216Australia

Zero trust architecture(ZTA)is a paradigm shift in how we protect data,stay connected and access resources.ZTA is non-perimeter-based defence,which has been emerging as a promising revolution in the cyber security field.It can be used to continuously maintain security by safeguarding against attacks both from inside and outside of the network system.However,ZTA automation and orchestration,towards seamless deployment on real-world networks,has been limited to be reviewed in the existing literature.In this paper,we first identify the bottlenecks,discuss the background of ZTA and compare it with traditional perimeter-based security architectures.More importantly,we provide an in-depth analysis of state-of-the-art AI techniques that have the potential in the automation and orchestration of ZTA.Overall,in this review paper,we develop a foundational view on the challenges and potential enablers for the automation and orchestration of ZTA.

关键词： Zero trust architecture cyber security artificial intelligence access control authentication

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A phase-field model for simulating the propagation behavior of mixed-mode cracks during the hydraulic fracturing process in fractured reservoirs

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 911-930页

作者： Dan ZHANG liangping YI Zhaozhong yang Jingqiang ZHANG gang CHEN Ruoyu yang Xiaogang li State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Tarim Oilfield Company PetroChinaBayingolin Mongolian Autonomous Prefecture 841000Xinjiang Uygur Autonomous RegionChina Wuqi Oil Production Plant Shaanxi Yanchang PetroleumXi'an 716000China Exploration Division of PetroChina Southwest Oil and Gasfield Company Chengdu 610041China

A novel phase-field model for the propagation of mixed-mode hydraulic fractures,characterized by the formation of mixed-mode fractures due to the interactions between fluids and solids,is proposed.In this model,the driving force for the phase field consists of both tensile and shear components,with the fluid contribution primarily manifesting in the tension driving force.The displacement and pressure are solved simultaneously by an implicit method.The numerical solution's iterative format is established by the finite element discretization and Newton-Raphson(NR)iterative methods.The correctness of the model is verified through the uniaxial compression physical experiments on fluid-pressurized rocks,and the limitations of the hydraulic fracture expansion phase-field model,which only considers mode I fractures,are revealed.In addition,the influence of matrix mode II fracture toughness value,natural fracture mode II toughness value,and fracturing fluid injection rate on the hydraulic fracture propagation in porous media with natural fractures is studied.

关键词： mixed-mode crack hydraulic fracturing poro-elasticity phase-field method(PFM)

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Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

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Rare Metals 2024年第7期43卷 3107-3117页

作者： Xin-yang liu Jing-Wei liu gang li Jing-Xiang Zhao College of Chemistry and Chemical Engineering Harbin Normal University

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and selectivity.In this work,by means of the density functional theory（DFT） calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM1-4@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions（OER）,oxygen reduction reactions（ORR） and hydrogen evolution reactions（HER）.The computed results reveal that the Pd2,Pd4and Pt1anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd1and Pt2@graphdiyne can exhibit excellent catalytic performance for water splitting（OER/HER） with the overpotentials of 0.55/0.17 and 0.43/0.03 V.In addition,Ni1and Pd3anchored GDY can perform as bifunctional catalysts for metal-air cells（OER/ORR） and fuels cells（ORR/HER） with the overpotentials of 0.34/0.32 and 0.42/0.04 V,respectively.Thus,by precisely controlling the numbers of atoms in clusters,the TM1-4anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

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A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1424-1437页

作者： Quanbo Ge yang Cheng Hong li Ziyi Ye Yi Zhu gang Yao School of Automation Nanjing University of Information Science&TechnologyJiangsu Provincial University Key Laboratory of Big Data Analysis and Intelligent SystemsNanjing University of Information Science&Technologyand the Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)Nanjing University of Information Science&TechnologyNanjing 210044China School of Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China China Classification Society Nantong Office Nantong 226006China Chinese Flight Test Establishment Xi’an 710089China School of Mathematics Tsinghua UniversityBeijing 100084China School of Automation Nanjing University of Information Science&TechnologyNanjing 210044China Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China IEEE

For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and symmetry.Some com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment.

关键词： Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.

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Revealing Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles in oxygen/fluorine containing environments:A reactive molecular dynamics study meshing together experimental validation

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Defence Technology（防务技术） 2024年第4期34卷 313-327页

作者： gang li Chuande Zhao Qian Yu Fang yang Jie Chen Institute of Chemical Materials China Academy of Engineering Physics(CAEP)P.O.Box 919-311Mianyang 621900SichuanChina

Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing environments.For instance,Al-O reaction is the most common pathway to release limited energy while Al-F reaction has received much attentions to enhance Al combustion efficiency.However,microscopic understanding of the Al-O/Al-F reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion efficiency.In this work,for the first time,Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion experiments.Three RMD simulation systems of Al core/O_(2)/HF,n-Al/O_(2)/HF,and n-Al/O_(2)/CF4 with oxygen percentage ranging from 0%to 100%have been performed.The n-Al combustion in mixed O_(2)/CF_4 environments have been conducted by constant volume combustion experiments.RMD results show that Al-O reaction exhibits kinetic benefits while Al-F reaction owns thermodynamic benefits for n-Al combustion.In n-Al/O_(2)/HF,Al-O reaction gives faster energy release rate than Al-F reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/HF and n-Al/O_(2)/CF_4,respectively.In combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion heat.Importantly,Al-O reaction prefers to occur on the surface regions while Al-F reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-F reactions.The synergistic effect of Al-O/Al-F reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.

关键词： Al-O/Al—F reaction Kinetic benefits Thermodynamic benefits Molecular dynamics Combustion

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