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Five Novel Pterocarpan Derivatives from Sophora flavescens

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Chinese Journal of Chemistry 2021年第10期39卷 2763-2768页

作者： Kai-Zhou Lu Zi-Ming Feng Xiang Yuan ya-nan yang Jian-Shuang Jiang Xu Zhang Pei-Cheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100050 China

Main observation and conclusion Five novel pterocarpan derivatives(1—5)and three known pterocarpans were isolated from the roots of Sophora flavescens *** structures were elucidated based on extensive spectroscopic data(UV,IR,1D and 2D NMR,and HR-ESI-MS).Notably,compounds 1—5 were the first reported natural products,which possess unique pterocarpan-glucose-long chain aliphatic acid *** kinds of aliphatic acids were determined by comparison with authentic aliphatic acids using HPLC-ELSD analysis after acid *** absolute configurations of 1—5 were confirmed by analysis of their ECD *** compounds were evaluated against lipopolysaccharide(LPS)-induced TNF-αproduction in RAW264.7 cells,and compound 1 showed significant inhibitory activity with inhibition rate of 86.22%,IC_(50)=0.79μmol/L(dexamethasone as positive control,inhibition rate of 71.38%).

关键词： Sophora flavescens Pterocarpan derivatives Natural products Structure elucidation Biological activity

Work Function Optimization Technology of Indium Tin Oxide Films

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Journal of Harbin Institute of Technology(New Series) 2021年第4期28卷 33-39页

作者： Bo Zhang Zhibo Zhang Xintao Guo ya’nan yang Ying Liu Lei yang Jiaqi Zhu Department of Materials Research AVIC Manufacturing Technology InstituteBeijing 100024China National Key Laboratory of Science and Technology on Advanced Composite in Special Environments Harbin Institute of TechnologyHarbin 150001China Center of Analysis and Measurement Harbin Institute of TechnologyHarbin 150001China

Indium tin oxide(In_(2)O_(3)∶Sn)film is one of the most potential materials in the field of semiconductor ***,untreated In2O3∶Sn film has a low work function which can result in a high energy barrier that hinders the passage of carriers through the interface,thus leading to poor overall performance of directly prepared *** this study,crystalline transparent conductive In_(2)O_(3)∶Sn films were prepared by plasma exposure assisted magnetron sputtering under room *** on multiple testing methods,it can be found that the low temperature crystallization characteristics of In_(2)O_(3)∶Sn film were enhanced and the work function was effectively improved after Ar^(+)plasma *** increase of the work function of In_(2)O_(3)∶Sn film was due to the increment of Sn⁃O bond on the surface brought by the transition from low oxidation state Sn^(2+)to high oxidation state Sn^(4+)under the action of high exposure.

关键词： work function indium tin oxide low temperature crystallization plasma exposure

Arnequinol A and arnequinone A, two unique meroterpenoids from Arnebia euchroma

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Chinese Chemical Letters 2022年第5期33卷 2555-2558页

作者： Hai-Wei yan Rong-Rong Du Xu Zhang ya-nan yang Xiang Yuan Zi-Ming Feng Jian-Shuang Jiang Pei-Cheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Arnequinol A(1),featuring an unprecedented 6/6/3 tricyclic carbon skeleton fused with a heptatomic oxo-bridge,together with arnequinone A(2)bearing a highly conjugated methyl-shifting benzogeijerene skeleton,were isolated from Arnebia *** structures were elucidated by extensive spectro-scopic methods and quantum chemical calculations of the 13 C nuclear magnetic resonance(NMR)data and electronic circular dichroism(ECD)*** plausible biosynthetic pathways for 1 and 2 were *** in vitro test,compound 2 showed potent neuroprotective activity against serum-deprivation induced PC12 cell damage at a concentration of 10μmol/L.

关键词： Arnebia euchroma Meroterpenoids Arnequinol A and arnequinone A Cytotoxicity Neuroprotective activity

Solution-processed rare-earth thulium oxide with high permittivity for low-voltage transistor and inverters applications

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Journal of Rare Earths 2024年第8期42卷 1604-1609,I0007页

作者： Daiming Liu Fei Wang Yongtao Zhang ya'nan Ding Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science&TechnologyQingdao266061China College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao266590China

The use of high-permittivity(high-k) thin films as gate dielectrics is essential in the development of lowpower electronics,In this work,rare-earth thulium oxide(Tm_(2)O_(3)) thin films were prepared by a facile solution process and annealed at various temperatures from 400 to 700℃.The evolution of the physical and dielectric properties of Tm_(2)O_(3) thin film with annealing temperature was *** is demonstrated that the Tm_(2)O_(3) thin film annealed at 600℃ exhibits the optimal performance,including a low leakage current of 3×10^(-10) A/cm^(2),a large areal capacitance of 250 nF/cm^(2) at 100 Hz,and a high permittivity value of *** Tm_(2)O_(3) thin film as a gate insulator was integrated into the thin film transistor(TFT) employing In_(2)O_(3)-based semiconducting *** In_(2)O_(3) TFT with 600℃-annealed Tm_(2)O_(3) dielectric exhibits the superior perfo rmance,with a high I_(on)/I_(off) of 1.65×10^(7),a small subthre shold swing(SS) value of 0.2 V/dec,a V_(TH) of+1.8 V,and a mobility of 1.68 cm^(2)/(V·s).Furthermore,an inverter constructed by connecting the TFT with a resistor exhibits full-swing *** work provides a facile and appealing method for preparing the high-k Tm_(2)O_(3) thin films as alternative gate dielectrics with the potential for use in low-power electronics and logic circuit applications.

关键词： Rare earths Tm_(2)O_(3) Dielectric Transistor Inverter

Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑nan Zong Hui Li ya‑Qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Bending results of graphene origami reinforced doubly curved shell

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Defence Technology（防务技术） 2024年第5期35卷 198-210页

作者： nan yang Yunhe Zou Mohammad Arefi School of Architecture and Civil Engineering Qiqihar UniversityQiqihar 161006HeilongjiangChina School of Mechanical Engineering Inner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina Inner Mongolia Key Laboratory of Special Service Intelligent Robotics Hohhot 010051Inner MongoliaChina Faculty of Mechanical Engineering Department of Solid MechanicsUniversity of KashanKashan87317-51167Iran

The present work investigates higher order stress,strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper(Cu)core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal *** effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both material properties of graphene and Cu in terms of temperature,volume fraction and folding *** principle of virtual work is used to derive governing equations with accounting thermal *** numerical results are analytically obtained using Navier's technique to investigate impact of significant parameters such as thermal loading,graphene amount,folding degree and directional coordinate on the stress,strain and deformation responses of the *** graphene origami materials may be used in aerospace vehicles and structures and defence technology because of their low weight and high stiffness.A verification study is presented for approving the formulation,solution methodology and numerical results.

关键词： Graphene origami Copper matrix Doubly curved Shear deformable Auxetic metamaterial

Localization for mixed near-field and far-field sources under impulsive noise

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Journal of Systems Engineering and Electronics 2024年第2期35卷 302-315页

作者： GAO Hongyuan ZHANG Yuze DU ya’nan CHENG Jianhua CHEN Menghan College of Information and Communication Engineering Harbin Engineering UniversityHarbin 150001China College of Intelligent Systems Science and Engineering Harbin Engineering UniversityHarbin 150001China

In order to solve the problem that the performance of traditional localization methods for mixed near-field sources(NFSs)and far-field sources(FFSs)degrades under impulsive noise,a robust and novel localization method is *** eliminating the impacts of impulsive noise by the weighted out-lier filter,the direction of arrivals(DOAs)of FFSs can be estimated by multiple signal classification(MUSIC)spectral peaks *** on the DOAs information of FFSs,the separation of mixed sources can be ***,the estimation of localizing parameters of NFSs can avoid two-dimension spectral peaks search by decomposing steering *** Cramer-Rao bounds(CRB)for the unbiased estimations of DOA and range under impulsive noise have been *** experiments verify that the proposed method has advantages in probability of successful estimation(PSE)and root mean square error(RMSE)compared with existing localization *** can be concluded that the proposed method is effective and reliable in the environment with low generalized signal to noise ratio(GSNR),few snapshots,and strong impulse.

关键词： source localization far-field source(NFS) near-field source(FFS) impulsive noise Cramer-Rao bound(CRB)

Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

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Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： ya yang Xiangzhen Kong Qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

FibroScan-aspartate transaminase:A superior non-invasive model for diagnosing high-risk metabolic dysfunction-associated steatohepatitis

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World Journal of Gastroenterology 2024年第18期30卷 2440-2453页

作者： Jing-ya Yin Tian-Yuan yang Bing-Qing yang Chen-Xue Hou Jun-nan Li Yue Li Qi Wang Center of Liver Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Pathology Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing institute of infectious disease Beijing 100015China Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)with hepatic histological NAFLD activity score≥4 and fibrosis stage F≥2 is regarded as“at risk”non-alcoholic steatohepatitis(NASH).Based on an international consensus,NAFLD and NASH were renamed as metabolic dysfunction-associated steatotic liver disease(MASLD)and metabolic dysfunction-associated steatohepatitis(MASH),respectively;hence,we introduced the term“high-risk MASH”.Diagnostic values of seven non-invasive models,including FibroScan-aspartate transaminase(FAST),fibrosis-4(FIB-4),aspartate transaminase to platelet ratio index(APRI),*** high-risk MASH have rarely been studied and compared in *** To assess the clinical value of seven non-invasive models as alternatives to liver biopsy for diagnosing high-risk *** A retrospective analysis was conducted on 309 patients diagnosed with NAFLD via liver biopsy at Beijing Ditan Hospital,between January 2012 and December *** screening for MASLD and the exclusion criteria,279 patients wereincluded and categorized into high-risk and non-high-risk MASH *** threshold values of each model,sensitivity,specificity,positive predictive value(PPV),and negative predictive values(NPV),were *** operating characteristic curves were constructed to evaluate their diagnostic efficacy based on the area under the curve(AUROC).RESULTS MASLD diagnostic criteria were met by 99.4%patients with *** MASLD population was analyzed in two cohorts:Overall population(279 patients)and the subgroup(117 patients)who underwent liver transient elastography(FibroScan).In the overall population,FIB-4 showed better diagnostic efficacy and higher PPV,with sensitivity,specificity,PPV,NPV,and AUROC of 26.9%,95.2%,73.5%,72.2%,and ***,Forns index,and aspartate transaminase to alanine transaminase ratio(ARR)showed moderate diagnostic efficacy,whereas S index and gamma-glutamyl transpeptidase to platelet ratio(GPR)were relatively *** the sub

关键词： Metabolic dysfunction-associated steatotic liver disease High-risk metabolic dysfunction-associated steatohepatitis Non-invasive models Liver biopsy Diagnostic value