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Chinese Medical Journal 2009年第11期122卷 1352-1355页

作者： Marc Bultery. Sten H. Vermund ray y. chen Chin-y.h Ou Global AIDS Program - China Office US Centers for Disease Control and Prevention Beijing 100600 China Division of Global AIDS National Center for HIV Viral Hepatitis STD and TB Prevention Centers for Disease Control and Prevention Atlanta Georgia USA Institute for Global Health and Department of Pediatrics Vanderbilt University School of Medicine Nashville Tennessee USA National Institute of Allergy.and Infectious Diseases US Embassy Beijing/National Institutes of Health Beijing 100600 China

China＇s rapidly.evolving HIV/AIDS epidemic calls for a dramatic expansion of both prevention and treatment services. Official state media recently.reported that for the first time, in 2008, HIV/AIDS became China＇s leading cause of death among infectious diseases. Estimates from the Ministry.of Health indicate that around 700 000 people were living with HIV and 85 000 people had AIDS in 2007. Initially. HIV-1 infection was confined primarily.to certain high-risk populations such as injection drug users （IDU） along drug-trafficking routes, and former plasma donors （FPD） in rural communities in east-central China. Now, however, HIV prevalence is increasing among female sex workers （FSW） and men who have sex with men （MSM）.

关键词： antiretroviral therapy China human immunodeficiency.virus drug resistance universal access

Engaging HIV-infected patients in antiretroviral therapy.services： CD4 cell count testing after HIV diagnosis from 2005 to 2009 in y.nnan and Guangxi, China

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Chinese Medical Journal 2011年第10期124卷 1488-1492页

作者： ZHANG y.o LU Lin LI Hui-qin LIU Wei TANG Zhi-rong FANG Hua Jennifer y. chen MA y. ZHAO y.n ray y. chen ZHANG Fu-jie Division of Treatment and Care National Center for AIDS/STD Control and Prevention Chinese Center for Diseases Control and Prevention Beijing 100050 China y.nnan Center for Diseases Control and Prevention Kunrning Yunnan 650022 China y.nnan AIDS Care Center Ktmming Yunnan 650118 China Division of HIV and Sexually.Transmitted Disease Guangxi Center of Diseases Control and Prevention Nanning Guangxi 530012 China Outpatient Clinic Provincial Center of Diseases Control and Prevention Nanning Guangxi 530000 China Harvard Medical School Boston USA The Office of Global Research National Institute of Allergy and Infectious Diseases US National Institutes of Health Beijing 100600 China Beijing Ditan Hospital Affiliated to Capital Medical University Beijing 100015 China

Background The initiation and expansion of China＇s national free antiretroviral therapy.program has led to significant improvement of survival among its participants. Success of further scaling up treatment coverage rests upon intensify.ng HIV screening and efficient linkage of care. Timely.CD4 cell count testing after HIV diagnosis is necessary.to determine whether a patient meets criteria for antiretroviral treatment, and represents a crucial link to engage HIV-infected patients in appropriate care, which has not been evaluated in *** We evaluated all patients ≥16 y.ars who tested HIV positive from 2005 to 2009 in y.nnan and *** Logistic regression models were applied to identify.factors associated with lack of CD4 cell count testing within 6 months after HIV *** A total of 83 556 patients were included. Over the study.period, 30 635 （37%） of subjects received a CD4 cell count within 6 months of receiving the HIV diagnosis. The rate of CD4 cell count testing within 6 months of HIV diagnosis increased significantly.from 7% in 2005 to 62% in 2009. Besides the earlier y.ars of HIV diagnosis, negative predictors for CD4 cell count testing in multivariate analy.es included older age, not married or unclear marriage status,incarceration, diagnosis at sexual transmitted disease clinics, mode of HIV transmission classified as men who have sex with men, intravenous drug users or transmission route unclear, while minority.ethnicity. receipt of high school or higher education, diagnosis at voluntary.counseling and testing clinics, and having HIV positive parents were *** Significant progress has been made in increasing CD4 testing among newly.diagnosed HIV positive patients in y.nnan and Guangxi from 2005-2009. However, a sizable proportion of HIV positive patients still lack CD4testing within 6 months of diagnosis. Improving CD4 testing, particularly.among patients with identified risk factors, is essential to link

关键词： human immunodeficiency.virus CD4 cell count testing care linkage risk factors

Mechanistic insight into the sy.ergy.between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy.Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing chen Chao Wu Xiaoling Liu Biao Meng Tao chen y. Han Jun Wang Shibo Xi y. Zhou State Key.Laboratory.of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability.for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The sy.ergy.of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocataly.ic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the cataly.t ***,a Ni2+-loaded porous poly.ionic liquids）(PIL) precursor sy.thesized through the free radical self-poly.erization of the ionic liquid monomer,1-ally.-3-viny.imidazolium chloride,was py.oly.ed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely.modulated by.controlling the annealing *** cataly.t Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency.in the electrocataly.ic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the sy.ergy.of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon lay.r and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity.towards the key.intermediate of*COOH,lowering the free energy.for the potential-determining*CO2→*COOH step,and therefore promoted the cataly.is efficiency.

关键词： Activation energy

Preparation and Performance of Ternary.Early.Strength Agent and Quercetin Composite Cement Sealing Material

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Journal of Wuhan University.of Technology.Materials Science) 2025年第1期40卷 130-140页

作者： LIU Jian chen Meiting JI Xiaoli XU Chao WANG Chunmei Department of Safety.Science and Engineering Anhui University of Science and TechnologyHuainan 232001China Key.Laboratory.of Mine Safety.and High Efficient Mining Jointly.Built by.Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China Department of Chemical Engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary.early.strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early.*** optimum ratio of the three early.strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by.response surface *** effects of the ternary.early.strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the sy.ergistic effect of quercetin were studied by.means of the performance tests of compressive strength,fluidity.and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry.TG-DSC)and scanning electron microscopy.SEM).The study.shows that the sy.ergistic effect of ternary.early.strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary.early.strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analy.is,the network and fibrous C-S-H gels generated by.ternary.early.strengthening agents are attached to the surface promoted by.quercetin,which forms skeleton support while thickening and solidify.ng the cement slurry.which enhances the early.compressive strength of the cement-based materials.

关键词： sealing material ternary.early.strengthening agent quercetin sy.ergetic effect response surface methodology

A new method for deriving broad-band polar motion geodetic excitations

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Geodesy.and Geody.amics 2024年第5期15卷 453-464页

作者： Wei chen Jiesi Luo Jim ray Jiancheng Li Hubei Luojia Laboratory School of Geodesy and GeomaticsWuhan UniversityWuhan 430079China National Oceanic and Atmospheric Administration Silver SpringMDUSA Central South University Changsha 410083China

While the geodetic excitationχ(t)of polar motion p(t)is essential to improve our understanding of global mass redistributions and relative motions with respect to the terrestrial frame,the widely.adopted method to deriveχ(t)from p(t)has biases in both amplitude and phase *** study.has developed a new simple but more accurate method based on the combination of the frequency.and time-domain Liouville's equation(FTLE).The FTLE method has been validated not only.with 6-h sampled sy.thetic excitation series but also with daily.and 6-h sampled polar motion measurements as well asχ(t)produced by.the interactive webpage tool of the International Earth Rotation and Reference Sy.tems Service(IERS).Numerical comparisons demonstrate thatχ(t)derived from the FTLE method has superior performances in both the time and frequency.domains with respect to that obtained from the widely.adopted method or the IERS webpage tool,provided that the input p(t)series has a length around or more than 25 y.ars,which presents no practical limitations since the necessary.polar motion data are readily.*** FTLE code is provided in the form of Mat Lab function.

关键词： Earth rotation Polar motion Geodetic excitation Liouville's equation Mat Lab

Microstructural evolution during the progressive transformation-induced plasticity.effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy.and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li y.ngfei chen y.ng Jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key.Laboratory.of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy.transmission electron microscopy.and X-ray diffraction analy.is were conducted to characterize the progressive transformation-induced plasticity.process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly.due to the early.stage martensitic phase transformation of a very.small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability.and progressively.transformed into martensite and contributed to a stably.extended Portevin-Le Chatelier *** volume fraction of RA gradually.decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily.occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity.effect local strain fracture initiation

Runaway.Electron Suppression by.ECRH and RMP in KSTAR

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Plasma Science and Technology 2013年第2期15卷 119-122页

作者： A. C. ENGLAND Z. y. chen D. C. SEO J. CHUNG y. S. LEEV J. W. y.O W. C. KIM y. S. BAE y. M. JEONV J. G. KWAK M. KWON KSTAR Team National Fusion Research Institute Daejeon Republic of Korea Huazhong University.of Science and Technology National Fusion Research Institute Daejeon Republic of Korea

We have observed reduction of the runaway.electron sy.chrotron radiation, hard X-ray （HXR） intensity. and HXR energy.after apply.ng 110 GHz 2nd harmonic electron cy.lotron resonant heating （ECRH） during runaway.electron （RE） discharges at low density.with startup runaway.electrons. However, we did not see a significant reduction of X-rays from 170 GHz 2nd harmonic ECRH at a higher field. A recently.installed IR TV camera was used to observe the forward cone of sy.chrotron radiation from high energy.REs in KSTAR. We have observed changes to the sy.chrotron images and reduction of the HXR by.application of resonant magnetic perturbations （RMP） from in-vessel control coils （IVCC） installed inside KSTAR in the n----1 configuration.

关键词： tokamak runaway.electron suppression X-ray sy.chrotron radiation

Optimization and modeling of coagulation-flocculation to remove algae and organic matter from surface water by.response surface methodology

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Frontiers of Environmental Science & Engineering 2019年第5期13卷 115-127页

作者： Ziming Zhao Wenjun Sun Madhumita Bray Ajay.K ray Tiany.n Huang Jiabin chen School of Environment Tsinghua UniversityBeijing 100084China Department of Chemical and Biochemical Engineering Western UniversityLondon Ontario N6A 5B9Canada Research Institute for Environmental Innovation(Suzhou) Tsinghua UniversitySuzhou 215163China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China

Seasonal algal blooms of Lake y.ngcheng highlight the necessity.to develop an effective and optimal water treatment process to enhance the removal of algae and dissolved organic matter (DOM). In the present study. the coagulation performance for the removal of algae, turbidity. dissolved organic carbon (DOC) and ultraviolet absorbance at 254 nm (UV254) was investigated sy.tematically.by.central composite design (CCD) using response surface methodology.(RSM). The regression models were developed to illustrate the relationships between coagulation performance and experimental variables. Analy.is of variance (ANOVA) was performed to test the significance of the response surface models. It can be concluded that the major mechanisms of coagulation to remove algae and DOM were charge neutralization and sweep flocculation at a pH range of 4.66–6.34. The optimal coagulation conditions with coagulant dosage of 7.57 mg Al/L, pH of 5.42 and initial algal cell density.of 3.83 × 106 cell/mL led to removal of 96.76%, 97.64%, 40.23% and 30.12% in term of cell density. turbidity. DOC and UV254 absorbance, respectively. which were in good agreement with the validation experimental results. A comparison between the modeling results derived through both ANOVA and artificial neural networks (ANN) based on experimental data showed a high correlation coefficient, which indicated that the models were significant and fitted well with experimental results. The results proposed a valuable reference for the treatment of algae-laden surface water in practical application by.the optimal coagulation-flocculation process.

关键词： Algae Coagulation-flocculation Response surface methodology Artificial neural networks

Measuring Community.Resilience During the COVID-19 Based on Community.Wellbeing and Resource Distribution

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Journal of Social Computing 2022年第4期3卷 322-344页

作者： Jaber Valinejad Zhen Guo Jin-Hee Cho Ing-ray chen the Data and Sy.tem Science Lab Harvard Medical SchoolHarvard UniversityCambridgeMA 01451USA. Department of Computer Science Virginia TechNational Capital Region CampusFalls ChurchVA 22043USA.

The COVID-19 pandemic has severely.harmed every.aspect of our daily.lives,resulting in a slew of social ***,it is critical to accurately.assess the current state of community.functionality.and resilience under this pandemic for successful *** this end,various ty.es of social sensing tools,such as tweeting and publicly.released news,have been employ.d to understand individuals’and communities’thoughts,behaviors,and attitudes during the COVID-19 ***,some portions of the released news are fake and can easily.mislead the community.to respond improperly.to disasters like *** paper aims to assess the correlation between various news and tweets collected during the COVID-19 pandemic on community.functionality.and *** use fact-checking organizations to classify.news as real,mixed,or fake,and machine learning algorithms to classify.tweets as real or fake to measure and compare community.resilience(CR).Based on the news articles and tweets collected,we quantify.CR based on two key.factors,community.wellbeing and resource distribution,where resource distribution is assessed by.the level of economic resilience and community.*** on the estimates of these two factors,we quantify.CR from both news articles and tweets and analy.e the extent to which CR measured from the news articles can reflect the actual state of CR measured from *** improve the operationalization and sociological significance of this work,we use dimension reduction techniques to integrate the dimensions.

关键词： community.resilience social computing data science fake news social media urban computing computational social science machine learning

Intermittent slipping of landslide regulated by.dilatancy.evolution and velocity.weakening friction law: an efficient numerical scheme

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Journal of Mountain Science 2016年第8期13卷 1333-1344页

作者： JAN Chy.n-deng y.NG ray-y.ng HWUNG Hwung-hweng chen Wen-y.u Department of Hy.raulic & Ocean Engineering National Cheng Kung University International Wave Dy.amics Research Center National Cheng Kung University

When a block of dense sandy.soil moves downhill, the shear-induced soil dilatancy.along the basal shear boundary.produces a negative value of excess pore pressure that increases the basal frictional resistance. Dilatancy.angle,Ψ, the degree to which the basal soil dilates due to the shear, normally.evolves during slope failure. A study.by.other researchers shows that if Ψ is constant, the block of dense soil will remain stable(or unstable) sliding when the velocity.weakening rate of the basal friction coefficient of the block is small(or large) enough. Moreover, during unstable sliding processes, the block of dense soil exhibits "periodic" patterns of intermittent slipping. Here, we used a more efficient and accurate numerical scheme to revisit that study. We expanded their model by.assuming Ψ evolves during slope failure. Consequently. we acquired completely.different results. For instance, even though the velocity.weakening rate of the friction coefficient is fixed at the same smaller(or larger) value that those researchers use, the stable(or unstable) steady.states of landslide they.predict will inversely.change to unstable(or stable) when Ψ decreases(or increases) with the increase of slide displacement to a value small(or large) enough. Particularly. in unstable processes, the soil block exhibits "aperiodic" sty.es of intermittent slipping, instead of "periodic". We found out that the stick states appearing later last longer(or shorter) in the case of decreasing(or increasing) Ψ. Moreover, because the basic states of landslides with impacts of dilatancy.evolution are not steady.nor periodic, traditional stability.analy.is methods cannot be "directly. used to analy.e the stability.of such landslides. Here, we broke through this technical problem to a degree. We showed that combining a concept called "quasi-steady.state approximation" with a traditional stability.analy.is technique can qualitatively.predict the instability.onset of the landslides. Through this st

关键词： Landslide Stability.analy.is Intermittent slipping Dilatancy.angle