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Symmetry quantification and segmentation in STEM imaging through Zernike moments

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Chinese Physics B 2024年第8期33卷 39-48页

作者： Jiadong Dan cheng Zhang 赵晓续 N.Duane Loh Department of Biological Sciences National University of SingaporeSingapore Center for Bioimaging Sciences(CBIS) National University of SingaporeSingapore Department of Physics National University of SingaporeSingapore School of Materials Science and Engineering Peking UniversityBeijing 100871China

We present a method using Zernike moments for quantifying rotational and reflectional symmetries in scanning transmission electron microscopy(STEM)images,aimed at improving structural analysis of materials at the atomic *** technique is effective against common imaging noises and is potentially suited for low-dose imaging and identifying quantum *** showcase its utility in the unsupervised segmentation of polytypes in a twisted bilayer TaS_(2),enabling accurate differentiation of structural phases and monitoring transitions caused by electron beam *** approach enhances the analysis of structural variations in crystalline materials,marking a notable advancement in the characterization of structures in materials science.

关键词： scanning transmission electron microscopy(STEM) symmetry segmentation

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苏合香品种变迁考

中国中药杂志 2024年第6期49卷 1690-1698页

作者：丁一明吴孟华 eric Brand 孙鑫刘越郭晓晗魏胜利马双成赵中振北京中医药大学中药学院北京100029 北京中医药大学本草纲目研究所北京100029 中国食品药品检定研究院北京102629 暨南大学岭南传统中药研究中心广东广州510632 北京中医药大学中医学院北京100029 香港浸会大学中医药学院中国香港00852

苏合香为我国常用进口中药材,在汉代即传入我国,苏合香作为中药始载于《名医别录》。该文通过梳理古今中外本草、现代文献资料,并结合对苏合香产地的实地考察结果,对苏合香的名称、质量评价、基原、产地及采收加工进行了系统的品种变迁... 详细信息

苏合香为我国常用进口中药材,在汉代即传入我国,苏合香作为中药始载于《名医别录》。该文通过梳理古今中外本草、现代文献资料,并结合对苏合香产地的实地考察结果,对苏合香的名称、质量评价、基原、产地及采收加工进行了系统的品种变迁考证。结果表明,自古以来苏合香便存在基原不明、产地不清的情况。我国历代医药学家多从质地、黏稠度、气味浓度、颜色4个方面对苏合香进行质量评价。苏合香品种共发生过2次变迁,第一次变迁可能在隋唐时期,基原由南欧安息香Sty⁃rax officinalis变迁为苏合香树Liquidambar orientalis。第二次变迁在近现代,基原由苏合香树变迁为北美枫香树***。在基原第二次变迁的同时,产地发生了第一次变迁,由小亚细亚南部地区的土耳其、叙利亚等国变迁为中美洲地区及北美洲南部地区的洪都拉斯、危地马拉等国。该文对苏合香质量评价、基原、产地、性状与采收加工等多方面的历史沿革进行了考证,同时对苏合香在西方国家的应用进行了综述,可为苏合香的进一步开发利用提供历史依据。

关键词：苏合香品种基原进口药材质量评价

Effects of SARS-CoV-2 infection on incidence and treatment strategies of hepatocellular carcinoma in people with chronic liver disease

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World Journal of Hepatology 2024年第2期16卷 211-228页

作者： Lung-Yi Mak Matthew Shing Hin Chung Xue Li Francisco Tsz Tsun Lai eric Yuk Fai Wan Celine Sze Ling Chui Franco Wing Tak cheng Esther Wai Yin Chan Ching Lung Cheung Ivan Chi Ho Au Xi Xiong Wai-Kay Seto Man-Fung Yuen Carlos King Ho Wong Ian Chi Kei Wong Department of Medicine The University of Hong KongHong KongChina State Key Laboratory of Liver Research The University of Hong KongHong KongChina Department of Pharmacology and Pharmacy The University of Hong KongHong KongChina Laboratory of Data Discovery for Health(D24H) Hong Kong Science and Technology ParkHong KongChina Department of Family Medicine and Primary Care The University of Hong KongHong KongChina School of Nursing The University of Hong KongHong KongChina School of Public Health The University of Hong KongHong KongChina Research Department of Practice and Policy University College LondonLondon WC1E 6BTUnited Kingdom Aston School of Pharmacy Aston UniversityBirmingham B47ETUnited Kingdom

BACKGROUND Chronic liver disease(CLD)was associated with adverse clinical outcomes among people with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** To determine the effects of SARS-CoV-2 infection on the incidence and treatment strategy of hepatocellular carcinoma(HCC)among patients with *** A retrospective,territory-wide cohort of CLD patients was identified from an electronic health database in Hong *** with confirmed SARS-CoV-2 infection[coronavirus disease 2019(COVID-19)+CLD]between January 1,2020 and October 25,2022 were identified and matched 1:1 by propensity-score with those without(COVID-19-CLD).Each patient was followed up until death,outcome event,or November 15,*** outcome was incidence of *** outcomes included all-cause mortality,adverse hepatic outcomes,and different treatment strategies to HCC(curative,non-curative treatment,and palliative care).Analyses were further stratified by acute(within 20 d)and post-acute(21 d or beyond)phases of SARS-CoV-2 *** rate ratios(IRRs)were estimated by Poisson regression *** Of 193589 CLD patients(>95%non-cirrhotic)in the cohort,55163 patients with COVID-19+CLD and 55163 patients with COVID-19-CLD were included after 1:1 propensity-score *** 249-d median follow-up,COVID-19+CLD was not associated with increased risk of incident HCC(IRR:1.19,95%CI:0.99-1.42,P=0.06),but higher risks of receiving palliative care for HCC(IRR:1.60,95%CI:1.46-1.75,P<0.001),compared to *** both acute and post-acute phases of infection,COVID-19+CLD were associated with increased risks of allcause mortality(acute:IRR:7.06,95%CI:5.78-8.63,P<0.001;post-acute:IRR:1.24,95%CI:1.14-1.36,P<0.001)and adverse hepatic outcomes(acute:IRR:1.98,95%CI:1.79-2.18,P<0.001;post-acute:IRR:1.24,95%CI:1.13-1.35,P<0.001),compared to *** Although CLD patients with SARS-CoV-2 infection were not associated with increased risk of HCC,they

关键词： SARS-CoV-2 infection Chronic liver disease Long COVID Post-COVID-19 syndrome Cirrhosis Hepatocellular carcinoma

Understanding the role of PIN1 in hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第45期22卷 9921-9932页

作者： Chi-Wai cheng Ka-Wai Leong eric Tse Department of Medicine The University of Hong Kong Queen Mary Hospital

PIN1 is a peptidyl-prolyl cis/trans isomerase that binds and catalyses isomerization of the specific motif comprising a phosphorylated serine or threonine residue preceding a proline(p Ser/Thr-Pro) in proteins. PIN1 can therefore induce conformational and functional changes of its interacting proteins that are regulated by proline-directed serine/threonine phosphorylation. Through this phosphorylation-dependent prolyl isomerization, PIN1 fine-tunes the functions of key phosphoproteins(e.g., cyclin D1, survivin, β-catenin and x-protein of hepatitis B virus) that are involved in the regulation of cell cycle progression, apoptosis, proliferation and oncogenic transformation. PIN1 has been found to be over-expressed in many cancers, including human hepatocellular carcinoma(HCC). It has been shown previously that overexpression of PIN1 contributes to the development of HCC invitro and in xenograft mouse model. In this review, we first discussed the aberrant transcription factor expression, miR NAs dysregulation, PIN1 gene promoter polymorphisms and phosphorylation of PIN1 as potential mechanisms underlying PIN1 overexpression in cancers. Furthermore, we also examined the role of PIN1 in HCC tumourigenesis by reviewing the interactions between PIN1 and various cellular and viral proteins that are involved in β-catenin, NOTCH, and PI3K/Akt/mT OR pathways, apoptosis, angiogenesis and epithelial-mesenchymal transition. Finally, the potential of PIN1 inhibitors as an anti-cancer therapy was explored and discussed.

关键词： Phosphorylation Hepatocellular carcinoma PIN1 Isomerization Hepatocarcinogenesis

AN IMPROVED MODAL ANALYSIS FOR THREE-DIMENSIONAL PROBLEMS USING FACE-BASED SMOOTHED FINITE ELEMENT METHOD

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Acta Mechanica Solida Sinica 2013年第2期26卷 140-150页

作者： Zhicheng He Guangyao Li Zhihua Zhong Aiguo cheng Guiyong Zhang eric Li State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Intelligent Systems for Medicine Laboratory School of Mechanical and Chemical EngineeringThe University of Western Australia35 Stirling HighwayCrawley WA 6009Australia Department of Mechanical Engineering National University of Singapore9 Engineering Drive 1117576Singapore

In this work, we further extended the face-based smoothed finite element method （FS-FEM） for modal analysis of three-dimensional solids using four-node tetrahedron elements. The FS-FEM is formulated based on the smoothed Calerkin weak form which employs smoothed strains obtained using the gradient smoothing operation on face-based smoothing domains. This strain smoothing operation can provide softening effect to the system stiffness and make the FSFEM provide more accurate eigenfrequency prediction than the FEM does. Numerical studies have verified this attractive property of FS-FEM as well as its ability and effectiveness on providing reliable eigenfrequency and eigenmode prediction in practical engineering application.

关键词： numerical method meshfree method modal analysis face-based smoothed finiteelement method (FS-FEM)

Thiopurines are negatively associated with anthropometric parameters in pediatric Crohn's disease

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World Journal of Gastroenterology 2018年第18期24卷 2036-2046页

作者： Neera Gupta Robert H Lustig Cewin Chao eric Vittinghoff Howard Andrews cheng-Shiun Leu Division of Gastroenterology and Nutrition Department of Pediatrics Weill Cornell Medicine Division of Endocrinology Department of Pediatrics University of CaliforniaSan Francisco Department of Nutrition and Food Services University of CaliforniaSan Francisco Department of Epidemiology and Biostatistics University of CaliforniaSan Francisco Department of Biostatistics Mailman School of Public Health Columbia University Department of Biostatistics Columbia University Medical Center

AIM To determine the distribution of anthropometric parameter(AP)-z-scores and characterize associations between medications/serum biomarkers and AP-z-scores in pediatric Crohn's disease(CD).METHODS CD patients [< chronological age(CA) 21 years] were enrolled in a cross-sectional study. Descriptive statistics were generated for participants' demographic characteristics and key variables of interest. Paired t-tests were used to compare AP-z-scores calculated based on CA(CA z-scores) and bone age(BA)(BA z-scores) for interpretation of AP's. Linear regression was utilized to examine associations between medications and serum biomarkers with AP-z-scores calculated based on CA(n = 82) and BA(n = 49). We reported regression coefficients as well as their corresponding p-values and 95% confidence *** Mean CA at the time of the study visit was 15.3 ± 3.5(SD; range = 4.8-20.7) years. Mean triceps skinfold(P = 0.039), subscapular skinfold(P = 0.002) and midarm circumference(MAC)(P = 0.001) BA z-scores were higher than corresponding CA z-scores. Medications were positively associated with subscapular skinfold [adalimumab(P = 0.018) and methotrexate(P = 0.027)] and BMI CA z-scores [adalimumab(P = 0.029)]. Azathioprine/6-mercaptopurine were negatively associated with MAC(P = 0.045), subscapular skinfold(P = 0.014), weight(P = 0.002) and BMI(P = 0.013) CA z-scores. ESR, CRP, and WBC count were negatively associated, while albumin and IGF-1 BA z-scores were positively associated, with specific AP z-scores(P < 0.05). Mean height CA z-scores were higher in females, not males, treated with infliximab(P = 0.038). Hemoglobin(P = 0.018) was positively associated, while platelets(P = 0.005), ESR(P = 0.003) and CRP(P = 0.039) were negatively associated with height CA z-scores in males, not females. CONCLUSION Our results suggest poor efficacy of thiopurines and a possible sex difference in statural growth response to infliximab in pediatric CD. Prospective longitudinal studie

关键词： Inflammatory bowel disease Azathioprine/6-mercaptopurine Biologics Nutrition

Long-term efficacy and safety of YAG laser vitreolysis for vision degrading myodesopsia

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International Journal of Ophthalmology(English edition) 2023年第11期16卷 1800-1805页

作者： Tie-Zhu Lin cheng Shi Xing Yang Emmanuel eric Pazo Yan-Nian Hui Li-Jun Shen Department of Ophthalmology Zhejiang Provincial People’s HospitalHangzhou 310000Zhejiang ProvinceChina He Eye Specialist Hospital Shenyang 110034Liaoning ProvinceChina Department of Ophthalmology Eye Institute of PLAXijing HospitalFourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina

AIM:To assess the long-term efficacy and safety of yttrium-aluminum garnet(YAG)laser vitreolysis for vision degrading myodesopsia(VDM)caused by posterior vitreous detachment(PVD).METHODS:This retrospective study reviewed VDM patients of PVD type undergoing YAG laser *** baseline demographic information,the patterns of floaters,the number of floaters,and the subjective improvement of floater sympotoms(ranging from 0 to 100%)from medical records were *** improvement was defined as a relief of floater symptoms of≥50%at the final *** long-term efficacy and safety of YAG laser vitreolysis were *** risk factors linked to significant improvement of floater symptoms were defined using univariate and multivariate logistic regression ***:The final analysis included 221 patients with *** mean age of patients was 61.08±7.74y,and the mean length of follow-up was 21.38±*** 57.01%of patients experienced a significant improvement in their floater symptoms after YAG laser therapy,and none of them developed delayed retinal abnormalities such as retinal tears or ***(OR=1.049,95%CI=1.007-1.092,P=0.021)was identified as a significant risk factor for significant improvement in ***:YAG laser vitreolysis is an effective and secure treatment for PVD-type VDM,and patients of advanced age are more likely to get favorable outcomes.

关键词： floaters posterior vitreous detachment YAG laser vitreolysis risk factors vision degrading myodesopsia

The Prospective Two-Dimensional Graphene Nanosheets: Preparation, Functionalization, and Applications

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Nano-Micro Letters 2012年第1期4卷 1-9页

作者： Zhi Yang Rungang Gao Nantao Hu Jing Chai Yingwu cheng Liying Zhang Hao Wei eric Siu-Wai Kong Yafei Zhang Key Laboratory for Thin Film and Microfabrication of the Ministry of Education Research Institute of Micro/Nano Science and Technology Shanghai Jiao Tong University

Graphene, as an intermediate phase between fullerene and carbon nanotube, has aroused much interests among the scientific community due to its outstanding electronic, mechanical, and thermal *** excellent electrical conductivity of 6000 S/cm, which is independent on chirality, graphene is a promising material for high-performance nanoelectronics, transparent conductor, as well as polymer composites. On account of its Young's Modulus of 1 TPa and ultimate strength of 130 GPa, isolated graphene sheet is considered to be among the strongest materials ever measured. Comparable with the single-walled carbon nanotube bundle,graphene has a thermal conductivity of 5000 W/(m·K), which suggests a potential application of graphene in polymer matrix for improving thermal properties of the graphene/polymer composite. Furthermore, graphene exhibits a very high surface area, up to a value of 2630 m^2/g. All of these outstanding properties suggest a wide application for this nanometer-thick, two-dimensional carbon material. This review article presents an overview of the significant advancement in graphene research: preparation, functionalization as well as the properties of graphene will be discussed. In addition, the feasibility and potential applications of graphene in areas, such as sensors, nanoelectronics and nanocomposites materials, will also be reviewed.

关键词： Graphene Graphite oxide Functionalization Sensors Transparent conductive films Nanocom posites

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新能源发电系统中的电力电子变换器(英文)

控制理论与应用 2008年第1期25卷 125-132页

作者：郑家伟香港理工大学电机工程系电力电子研究中心中国香港红勘

讨论了太阳能发电和风力发电的条件及其适应器,并且对各种最大功率点跟踪方法进行验证.论文研究了电力电子变换器拓扑技术在最大功率点跟踪及电压变换方面的应用.另外,发电系统还包括:逆变器驱动电路,蓄电池充电器,DC-DC和AC-AC电力变换... 详细信息

讨论了太阳能发电和风力发电的条件及其适应器,并且对各种最大功率点跟踪方法进行验证.论文研究了电力电子变换器拓扑技术在最大功率点跟踪及电压变换方面的应用.另外,发电系统还包括:逆变器驱动电路,蓄电池充电器,DC-DC和AC-AC电力变换器.本文对新能源领域中电力变换器及其驱动电路的最新发展做了全面的综述;其中,重点介绍了所用到的不同的最大功率跟踪方法并给用到的各种类型进行简单描述.

关键词：电力电子变换器最大功率点追踪新能源