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Retrospect and Prospect of Higher Education in Chinese Medicine in Hong Kong,China

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Chinese Journal of Integrative Medicine 2017年第7期23卷 494-495页

作者： zhao Zhong-zhen School of Chinese Medicine Hong Kong Baptist UniversityHong Kong SAR China

It has been 16 years since the first courses on Chinese medicine （CM） at Hong Kong Baptist University （HKBU） were *** can be said that the advancement o f CM education is a microcosm of the development of the CM in Hong Kong *** a past course director,I was closely involved with colleagues and students in this unforgettable *** Years of Difficulty Have Laid the Foundation for A Bright Future

关键词： Baptist courses director Bright created advancement curriculum pharmacy Australia earned

Aircraft Observations of Liquid and Ice in Midlatitude Mixed-Phase Clouds

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Advances in Atmospheric Sciences 2014年第3期31卷 604-610页

作者： zhao zhen LEI Hengchi Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences

ABSTRACT This paper reports airborne measurements of midlatitude altostratus clouds observed over zhengzhou, Henan Province, China on 3 March 2007. The case demonstrates mixed-phase conditions at altitudes from 3200 to 4600 m （0°C to -7.6°C）, with liquid water content ranging from 0.01 to 0.09 g m-3. In the observed mixed-phase cloud, liquid water content exhibited a bimodal distribution, whereas the maximum ice particle concentration was located in the middle part of the cloud. The liquid and ice particle data showed significant horizontal variability on the scale of a few hundred meters. The cloud droplet concentration varied greatly over the horizontal sampling area. There was an inverse relationship between the cloud droplet concentration and ice particle concentration. A gamma distribution provided the best description of the cloud droplet spectra. The liquid droplet distributions were found to increase in both size and concentration with altitude. It was inferred from the profile of the spectra parameters that the cloud droplet sizes tend to form a quasi-monodisperse distribution. Ice particle spectra in the cloud were fitted well by an exponential distribution. Finally, a remarkable power law relationship was found between the slope （λ） and intercept （No） parameters of the exponential size distribution.

关键词： cloud structure liquid water content droplet spectra particle measuring systems

A novel phenomenological model using a sine function for finite-element simulation of large-strain hot deformation

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Science China(Technological Sciences) 2018年第5期61卷 748-760页

作者： ZENG Fan HU ChengLiang zhao zhen Institute of Forming Technology & Equipment Shanghai Jiao Tong University

In hot deformation, the flow stress curves of steels always present as two typical types: at relatively high temperature and low strain rate, the flow stress may first increase and then attain a steady value without reaching an obvious peak stress; in other situations, the flow stress decreases after reaching peak stress and then attains a steady value. A new phenomenological model,described by a sine-function equation, is proposed to define the relationship between flow stress and deformation parameters. A series of isothermal compressions for a carbon steel were carried out, as a case study, to obtain basic experimental *** of the new model were sequentially determined. The predicted results of the proposed model were compared with actual measured data. Good accuracy was found in the standard statistical parameters of correlation coefficient, root mean square error, and average absolute relative error with the values of 0.935, 7.137 MPa and 4.352%, respectively. Discussion of applications of different models in finite-element simulation demonstrated the benefit of the new model. When comparing the simulation results of three different deformation patterns with large strain, the new model showed 10%–20% lower predicted forming load than the original Arrhenius equation, and better applicability and reliability than modified Arrhenius equations.

关键词： phenomenological model high temperature large strain finite-element simulation

Experimental and numerical investigation of failure mode in geometrically imperfect DP590 steel

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Science China(Technological Sciences) 2015年第3期58卷 476-484页

作者： ZHUANG XinCun XU Cheng zhao zhen Institute of Forming Technology & Equipment School of Materials Science and Engineering Shanghai Jiaotong University

Various microstructure-level finite element models were generated according to the real microstructure of DP590 steel to capture the mechanical behavior and fracture *** failure mode of the dual-phase(DP)steels,mainly resulting from microstructure-level inhomogeneity and initial geometrical imperfection,was predicted using the plastic strain localization *** addition,dog-bone-type tensile test specimens with different edge qualities were prepared and the deformation processes were recorded using a digital image correlation *** the steel exhibited no initial geometrical imperfection,void initiation was triggered by decohesion between martensite and ferrite which was predicted based on the severe strain concentration,or tensile stress in areas where stress triaxiality and strain values were *** failure was caused by shear localization in the ***,the initial geometrical imperfections severely affected the overall ductility and failure mode of the *** initial geometrical imperfections were deeply ingrained,an incipient crack began at the site of initial geometrical imperfection,and then caused progressive damage throughout the microstructure,from the area of shear localization to the final ***,the depth of the geometrical imperfection was the critical factor in determining whether internal decohesion or a local crack plays a dominant role.

关键词： representative volume element dual-phase(DP) steel geometrical imperfection failure mode

Non-uniform heat transfer behavior during shell solidification in a wide and thick slab continuous casting mold

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 240-250页

作者： zhao-zhen Cai Miao-yong Zhu School of Materials and Metallurgy Northeastern University

By employing a two-dimensional transient thermo-mechanical coupled finite element model for simulating shell heat transfer behaviors within a slab continuous casting mold, we predicted the evolution of shell deformation and the thermal behaviors, including the mold flux film dynamical distribution, the air gap formation, as well as the shell temperature field and the growth of carbon steel solidification, in a 2120 mm × 266 mm slab continuous casting mold. The results show that the shell server deformation occurs in the off-corners in the middle and lower parts of the mold and thus causes the thick mold flux film and air gap to distribute primarily in the regions of 0–140 mm and 0–124 mm and 0–18 mm and 0–10 mm, respectively, from the corners of the wide and narrow faces of the shell under typical casting conditions. As a result, the hot spots, which result from the thick mold flux film filling the shell/mold gap, form in the regions of 20–100 mm from the corners of the wide and narrow faces of the shell and tend to expand as the shell moves downward.

关键词： continuous casting molds heat transfer solidification finite element method

Optimal transmission strategy for spatially correlated MIMO systems with channel statistical information

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 615-619页

作者： zhao zhen-shan XU Guo-zhi Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

In real multiple-input multiple-output (MIMO) systems, the perfect channel state information (CSI) may be costly or impossible to acquire. But the channel statistical information can be considered relatively stationary during long-term transmission. The statistical information can be obtained at the receiver and fed back to the transmitter and do not require frequent update. By exploiting channel mean and covariance information at the transmitter simultaneously, this paper investigates the optimal trans- mission strategy for spatially correlated MIMO channels. An upper bound of ergodic capacity is derived and taken as the per- formance criterion. Simulation results are also given to show the performance improvement of the optimal transmission strategy.

关键词： MIMO Optimal transmission strategy Channel statistical information

Recent progress on the activation of the cGAS–STING pathway and its regulation by biomolecular condensation

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Journal of Molecular Cell Biology 2022年第6期14卷 1-13页

作者： Xiaoyu Yu zhen zhao zhengfan Jiang Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education School of Life SciencesPeking UniversityBeĳing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeĳing 100871China

The cyclic guanosine monophosphate (GMP)–adenosine monophosphate (AMP) synthetase (cGAS)–stimulator of interferon genes(STING) pathway, comprising the DNA sensor cGAS, the second messenger cyclic GMP–AMP (cGAMP), and the endoplasmicreticulum (ER) adaptor protein STING, detects cytoplasmic double-stranded DNA (dsDNA) to trigger type I-interferon responses forhost defense against pathogens. Previous studies defined a model for the allosteric activation of cGAS by DNA-binding, but recentwork reveals other layers of mechanisms to regulate cGAS activation such as the phase condensation and metal ions, especially thediscovery of Mn^(2+) as a cGAS activator. Activation of the 23-cGAMP sensor STING requires translocating from the ER to the Golgiapparatus. The sulfated glycosaminoglycans at the Golgi are found to be the second STING ligand promoting STING oligomerizationand activation in addition to 23-cGAMP, while surpassed levels of 23-cGAMP induce ER-located STING to form a highly organizedER membranous condensate named STING phase-separator to restrain STING activation. Here, we summarize recent advances in theregulation of cGAS–STING activation and their implications in physiological or pathological conditions, particularly focusing on theemerging complexity of the regulation.

关键词： innate immunity cGAS-STING cGAMP manganese(Mn2+) sulfated glycosaminoglycans(sGAGs) biomolecular condensate STING phase-separator

Synthesis of 3-(1-Cyclohexenyl)-2-butanone via Environmentally Friendly Catalysts

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Chemical Research in Chinese Universities 2003年第3期19卷 350-354页

作者： zhao zhen-hua Department of Applied Chemistry and Environmental Science Changsha UniversityChangsha 410003P.R.China

We substituted several environmentally friendly catalysts which included HY and H- β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synthesis of 3-(1-cyclohexenyl)-2-butanone from the reaction of ethylidenecyclohexane with acetic anhydride at room temperature. HY zeolite was found to be the most effective for this reaction, and gave the acylated product in a 72% yield under the conditions of n (ethylidenecyclohexane)/ n (acetic anhydride)/ m (HY zeolite)=1 mmol/10 mmol/0 100 g, reaction temperature 25 ℃ and reaction time 2 h. The used HY zeolite can be recovered, regenerated and gave almost the same yield as the fresh one. The lifetime of the HY zeolite is over 80 h. The effect of different factors on the reaction has also been investigated.

关键词： Acylation Zeolite Environmentally friendly catalyst 3-(1-Cyclohexenyl)-2-butanone Ethylidenecyclohexane Acetic anhydride Synthesis

Vascular inflammation in the central nervous system

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Neural Regeneration Research 2022年第8期17卷 1728-1730页

作者： Xinying Guo zhen zhao Center for Neurodegeneration and Regeneration Zilkha Neurogenetic Institute and Department of Physiology and NeuroscienceKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA Neuroscience Graduate Program Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA

Vasculature is the interface between tissue and *** consists of endothelial cells,mural cells including vascular smooth muscle cells and pericytes,and other perivascular cells including macrophages and fibroblasts(Sweeney et al.,2019).The vascular system not only delivers oxygen and nutrients,but also shuttles the immune cells *** the first line of defense,the vascular system also senses the changes in surrounding tissue,particularly *** inflammation can occur in blood vessels of all sizes in any *** has a complex etiology,including infections such as coronavirus disease-19(COVID-19),and chronic condi t ions such as diabetes,hypertension and neurodegenerative diseases(Hanafi et al.,2020).Excessive vascular inflammation is clinically known as vasculitis,diagnosed by blood test,imaging and *** not only thickens the blood vessel wall,causing blood flow reduction and insufficient delivery of oxygen and nutrients,but also triggers inflammatory responses in secondary sites,or even the whole body.

关键词： inflammation al. Vascular