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Particuology 2014年第4期12卷 9-17页

作者： Jung Hoon Chae george Zheng Chen Department of Chemical and Environmental Engineering and Energy and Sustainability Research DivisionFaculty of EngineeringUniversity of NottinghamNottinghamNG7 2RDUK

A commercial product of carbon nano-particles, Cabot MONACH 1300 pigment black （CMPB）, was studied for basic structural information and electrochemical performance in neutral aqueous electrolytes, aiming at applications in supercapacitors. As confirmed by SEM and HRTEM, the CMPB had a hierarchical struc- ture, containing basic 10 nm nano-spheres which combined into ca. 50 nm agglomerates which further aggregated into larger particles of micrometres. The capacitance of this commercial material was found to increase with decreasing the size of hydrous cation （Li＋→Na＋ → K＋）, instead of the cation crystal radius （K＋→ Na＋→Li＋） when coupled with the same anion （cl-）. In electrolytes with the same cation concentration （K＋）, changing the anion from the larger dianion （SO42 ） to the smaller monoanion （cl-） also increased the capacitance at high potential scan rates （〉50 mV/s）. Increasing electrolyte concentration produced expected effect, including raising the electrode capacitance, but lowering the equivalent series resistance （ESR）, charge transfer resistance （CTR）, and the diffusion resistance. At higher temperatures, the CMPB exhibited slightly higher capacitance, which does not agree with the Gouy-Chapman theory on electric double layer （EDL）. A hypothesis is proposed to account for the capacitance increase with temperature as a result of the CMPB opening up some micro-pores for more ions to access in response to the temperature increase.

关键词： Carbon nano-particlesSupercapacitorNeutral aqueous electrolytesIonic propertiesElectrochemistry

Occult hepatitis B—the result of the host immune response interaction with different genomic expressions of the virus

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World Journal of Clinical Cases 2022年第17期10卷 5518-5530页

作者： george Sebastian Gherlan Department of Infectious Diseases “Carol Davila”University of Medicine and PharmacyBucharest 030303Romania Department of Infectious Diseases “Dr.Victor Babes”Hospital of Infectious and Tropical DiseasesBucharest 030303Romania

With over 40 years of history,occult hepatitis B infection(OBI)continues to remain an important and challenging public health *** as the presence of replication-competent hepatitis B virus(HBV)DNA(i.e.,episomal HBV covalently closed circular DNA)in the liver and/or HBV DNA in the blood of people who test negative for hepatitis B surface antigen(HBsAg)in currently available assays,OBI is currently diagnosed using polymerase chain reaction(PCR)and real-time PCR ***,all efforts should be made to exclude a false negative HBsAg in order to completely follow the definition of *** recent years,significant advances have been made in understanding the HBV lifecycle and the molecular mechanisms that lead to the persistence of the virus in the occult *** factors are mainly related to the host immune system and,to a smaller proportion,to the *** innate and adaptive immune responses are important in HBV infection management,and epigenetic changes driven by host mechanisms(acetylation,methylation,and microRNA implication)are added to such *** greater genetic variability in the S gene of HBV isolated from OBIs was found compared with overt infection,the mechanisms of OBI are not mainly viral mutations.

关键词： Hepatitis B virus Occult hepatitis B Covalently closed circular DNA Epigenetic factors Immune factors MicroRNA

Towards multiple hazard resilient bridges:a methodology for modeling frequent and infrequent time-varying loads Part I,Comprehensive reliability and partial failure probabilities

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 293-301页

作者： Zach Liang george C.Lee Department of Mechanical and Aerospace Engineering University at Buffalo Department of Civil Structural and Environmental EngineeringUniversity at Buffalo

The current AASHTO load and resistance factor design （LRFD） guidelines are formulated based on bridge reliability, which interprets traditional design safety factors into more rigorously deduced factors based on the theory of probability. This is a major advancement in bridge design specifications. However, LRFD is only calibrated for dead and live loads. In cases when extreme loads are significant, they need to be individually assessed. Combining regular loads with extreme loads has been a major challenge, mainly because the extreme loads are time variables and cannot be directly combined with time invariant loads to formulate the probability of structural failure. To overcome these difficulties, this paper suggests a methodology of comprehensive reliability, by introducing the concept of partial failure probability to separate the loads so that each individual load combination under a certain condition can be approximated as time invariant. Based on these conditions, the extreme loads （also referred to as multiple hazard or MH loads） can be broken down into single effects. In Part II of this paper, a further breakdown of these conditional occurrence probabilities into pure conditions is discussed by using a live truck and earthquake loads on a bridge as an example. There are three major steps in establishing load factors from MH load distributions：（1） formulate the failure probabilities; （2） normalize various load distributions; and （3） establish design limit state equations. This paper describes the formulation of the failure probabilities of single and combined loads.

关键词： multiple hazards bridge probability-based design comprehensive reliability partial failure probability

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Interspecies transmission and host restriction of avian H5N1 influenza virus

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Science China(Life Sciences) 2009年第5期52卷 428-438页

作者： GAO george Fu CAS Key Laboratory of Pathogenic Microbiology and Immunology (CASPMI) Institute of Microbiology Chinese Academy of Sci-ences (CAS) Beijing Institutes of Life Science (BioLS) Chinese Academy of Sciences (CAS)

Long-term endemicity of avian H5N1 influenza virus in poultry and continuous sporadic human infections in several countries has raised the concern of another potential pandemic influenza. Suspicion of the avian origin of the previous pandemics results in the close investigation of the mechanism of interspecies transmission. Entry and fusion is the first step for the H5N1 influenza virus to get into the host cells affecting the host ranges. Therefore receptor usage study has been a major focus for the last few years. We now know the difference of the sialic acid structures and distributions in different species, even in the different parts of the same host. Many host factors interacting with the influenza virus component proteins have been identified and their role in the host range expansion and interspecies transmission is under detailed scrutiny. Here we review current progress in the receptor usage and host factors.

关键词： H5N1 influenza virus interspecies transmission virus adaptation host factors

Towards establishing practical multi-hazard bridge design limit states

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Earthquake Engineering and Engineering Vibration 2013年第3期12卷 333-340页

作者： Zach Liang george C.Lee Department of Mechanical and Aerospace Engineering Unidersity at Buffalo Depart of Civil Structural and Environmental Engineering University at Buffalo

In the U.S., the current Load and Resistance Factor Design （LRFD） Specifications for highway bridges is a reliability-based formulation that considers failure probabilities of bridge components due to the actions of typical dead load and frequent vehicular loads. Various extreme load effects, such as earthquake and vessel collision, are on the same reliability-based platform. Since these extreme loads are time variables, combining them with not considered frequent. non- extreme loads is a significant challenge. The number of design limit state equations based on these failure probabilities can be unrealistically large and unnecessary from the view point of practical applications. Based on the opinion of AASHTO State Bridge Engineers, many load combinations are insignificant in their states. This paper describes the formulation of a criterion to include only the necessary load combinations to establish the design limit states. This criterion is established by examining the total failure probabilities for all possible time-invariant and time varying load combinations and breaking them down into partial terms. Then, important load combinations can be readily determined quantitatively,

关键词： multi-hazards load and resistance factor design re.liability based bridge design specifications design limit state equations

Na^+/K^+-ATPase β1 subunit interacts with M2 proteins of influenza A and B viruses and affects the virus replication

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Science China(Life Sciences) 2010年第9期53卷 1098-1105页

作者： GAO george Fu CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences Graduate University Chinese Academy of Sciences Beijing Institutes of Life Sciences Chinese Academy of Sciences

Interplay between the host and influenza virus has a pivotal role for the outcome of *** matrix proteins M2/BM2 from influenza (A and B) viruses are small type III integral membrane proteins with a single transmembrane domain,a short amino-terminal ectodomain and a long carboxy-terminal cytoplasmic *** function as proton channels,mainly forming a membrane-spanning pore through the transmembrane domain tetramer,and are essential for virus assembly and release of the viral genetic materials in the endosomal fusion ***,little is known about the host factors which interact with M2/BM2 proteins and the functions of the long cytoplasmic domain are currently *** with yeast two-hybrid screening and applying a series of experiments we identified that the β1 subunit of the host Na+/K+-ATPase β1 subunit (ATP1B1) interacts with the cytoplasmic domain of both the M2 and BM2 proteins.A stable ATP1B1 knockdown MDCK cell line was established and we showed that the ATP1B1 knockdown suppressed influenza virus A/WSN/33 replication,implying that the interaction is crucial for influenza virus replication in the host *** propose that influenza virus M2/BM2 cytoplasmic domain has an important role in the virus-host interplay and facilitates virus replication.

关键词： influenza virus M2 protein Na+/K+-ATPase β1 subunit interaction virus replication

From the editors:special issue announcement

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 251-261页

作者： Wang Zhiqiang george C. Lee Department of Bridge Engineering Tongji University Shanghai 200092 China Department of Civil Structural and Environmental Engineering University at Buffalo State University of New York USA

A comparative study of selected bridge damage due to the Wenchuan, Northridge, Loma Prieta and San Fernando earthquakes is described in this paper. Typical ground motion effects considered include large ground fault displacement, liquefaction, landslide, and strong ground shaking. Issues related to falling spans, inadequate detailing for structural ductility and complex bridge configurations are discussed within the context of the recent seismic design codes of China and the US. A significant lesson learned from the Great Wenchuan earthquake, far beyond the opportunities to improve the seismic design provisions for bridges, is articulated.

关键词： bridge damage Wenchuan earthquake Northridge earthquake Loma Prieta earthquake San Fernandoearthquake ground motion liquefaction landslide

2-D eddy resolving simulations of flow past a circular array of cylindrical plant stems

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Journal of Hydrodynamics 2018年第2期30卷 317-335页

作者： Kyoungsik Chang george Constantinescu Sanghyun Park School of Mechanical Engineering Ulsan University Ulsan Korea Civil and Environmental Engineering Department IIHR-Hydroscience and Engineering Stanley Hydraulics Laboratory The University of Iowa Iowa City USA Korea Aerospace Research Institute Daejeon Korea

In the present study, 2-D large eddy simulations（LES） are conducted for flow past a porous circular array with a solid volume fraction（SVF） of 8.8%, 15.4% and 21.5%. Such simulations are relevant to understanding flow in natural streams and channels containing patches of emerged vegetation. In the simulations discussed in the paper, the porous cylinder of diameter D contains a variable number of identical solid circular cylinders（rigid plant stems） of diameter d= 0.048 D. Most of the simulations are conducted at a Reynolds number of 2 100 based on the diameter D and the velocity of the steady uniform incoming flow. Though in all cases wake billows are shed in the regions where the separated shear layers（SSLs） forming on the sides of the porous cylinder interact, the effect of these wake billows on the mean drag is different. While in the high SVF case（21.5%）, the total drag force oscillates quasi-regularly in time, similar to the canonical case of a large solid cylinder, in the cases with a lower SVF the shedding of the wake billows takes place sufficiently far from the cylinder such that the unsteady component of the total drag force is negligible. The mean amplitude of the oscillations of the drag force on the individual cylinders is the largest in a streamwise band centered around the center of the porous cylinder, where the wake to wake interactions are the strongest. In all cases the maximum drag force on the individual cylinders is the largest for the cylinders directly exposed to the flow, but this force is always smaller than the one induced on a small isolated cylinder and the average magnitude of the force on the cylinders directly exposed to the flow decreases monotonically with the increase in the SVF. Predictions of the global drag coefficients, Strouhal numbers associated with the wake vortex shedding and individual forces on the cylinders in the array from the present LES are in very good agreement with those of 2-D direct numerical simulations conduc

关键词： Vegetation eddy resolving simulation solid volume fraction porous cylinder bleeding flow

Bridge pier failure probabilities under combined hazard effects of scour, truck and earthquake. Part Ⅰ: occurrence probabilities

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 229-240页

作者： Zach Liang george C. Lee Department of Mechanical and Aerospace Engineering Unidersity at Buffalo Depart of Civil Structural and Environmental EngineeringUniversity at Buffalo

In many regions of the world, a bridge will experience multiple extreme hazards during its expected service life. The current American Association of State Highway and Transportation Officials （AASHTO） load and resistance factor design （LRFD） specifications are formulated based on failure probabilities, which are fully calibrated for dead load and nonextreme live loads. Design against earthquake loads is established separately. Design against scour effect is also formulated separately by using the concept of capacity reduction （or increased scour depth）. Furthermore, scour effect cannot be linked directly to an LRFD limit state equation, because the latter is formulated using force-based analysis. This paper （in two parts） presents a probability-based procedure to estimate the combined hazard effects on bridges due to truck, earthquake and scour, by treating the effect of scour as an equivalent load effect so that it can be included in reliability-based bridge failure calculations. In Part I of this series, the general principle of treating the scour depth as an equivalent load effect is presented. The individual and combined partial failure probabilities due to truck, earthquake and scour effects are described. To explain the method of including non-force-based natural hazards effects, two types of common scour failures are considered. In Part 11, the corresponding bridge failure probability, the occurrence of scour as well as simultaneously having both truck load and equivalent scour load are quantitatively discussed.

关键词： multi-hazards load and resistance factor design bridge scour

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SARS-CoV-2 induced liver injury:Incidence,risk factors,impact on COVID-19 severity and prognosis in different population groups

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World Journal of Gastroenterology 2023年第16期29卷 2397-2432页

作者： george D Liatsos Department of Internal Medicine Hippokration General HospitalAthens 11527AttikiGreece

Liver is unlikely the key organ driving mortality in coronavirus disease 2019(COVID-19)however,liver function tests(LFTs)abnormalities are widely observed mostly in moderate and severe *** to this review,the overall prevalence of abnormal LFTs in COVID-19 patients ranges from 2.5%to 96.8%*** geographical variability in the prevalence of underlying diseases is the determinant for the observed discrepancies between East and *** mechanisms are implicated in COVID-19-induced liver *** them,hypercytokinemia with“bystander hepatitis”,cytokine storm syndrome with subsequent oxidative stress and endotheliopathy,hypercoagulable state and immuno-thromboinflammation are the most determinant mechanisms leading to tissue *** hypoxia may also contribute under specific conditions,while direct hepatocyte injury is an emerging *** for initially observed severe acute respiratory distress syndrome corona virus-2(SARS-CoV-2)tropism for cholangiocytes,more recent cumulative data show SARS-CoV-2 virions within hepatocytes and sinusoidal endothelial cells using electron microscopy(EM).The best evidence for hepatocellular invasion by the virus is the identification of replicating SARS-CoV-2 RNA,S protein RNA and viral nucleocapsid protein within hepatocytes using in-situ hybridization and immunostaining with observed intrahepatic presence of SARS-CoV-2 by EM and by in-situ *** data mostly derived from imaging findings indicate possible long-term sequelae for the liver months after recovery,suggesting a post-COVID-19 persistent live injury.

关键词： COVID-19 SARS-CoV-2 Liver injury Cytokine storm Endotheliopathy Immuno-thromboinflammation Direct hepatocyte injury