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A Perspective on Studying Electronic Structure of Batteries through Soft X-ray Spectroscopy

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Chinese Journal of Structural Chemistry 2019年第12期38卷 2009-2014页

作者： ZHUO zeng-qing PAN Feng YANG wan-Li School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen 518055China Advanced Light Source Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeley CA 94720United States

Understanding electronic structure is crucial to enhance the battery performance. Soft X-ray spectroscopy(SXS) is one of the most effective methods to provide direct probe of electronic states. Here, spectroscopic measurements of transition metal 3 d and oxygen 2 p states are simply reviewed. Then, we mainly focus on the perspective of the development direction of modern SXS techniques. Although the true power of recently developed high efficiency mapping of resonant inelastic X-ray scattering(m RIXS) has been apparent for materials and chemistry studies, great challenges remain for mRIXS spectroscopic interpretation, and the understanding of the battery materials on novel redox activities remains elusive.

关键词： electronic structure soft X-ray spectroscopy oxygen redox O-K mRIXS

Survival benefit of younger gastric cancer patients in China and the United States:A comparative study

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World Journal of Gastroenterology 2023年第6期29卷 1090-1108页

作者： Peng-Hui Niu Lu-Lu Zhao wan-qing wang Xiao-Jie Zhang ze-Feng Li Xiao-Yi Luan Ying-Tai Chen Department of Pancreatic and Gastric Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

BACKGROUND The impact of racial and regional disparity on younger patients with gastric cancer(GC) remains *** To investigate the clinicopathological characteristics, prognostic nomogram, and biological analysis of younger GC patients in China and the United *** From 2000 to 2018, GC patients aged less than 40 years were enrolled from the China National Cancer Center and the Surveillance Epidemiology and End Results database. Biological analysis was performed based on the Gene Expression Omnibus database. Survival analysis was conducted via Kaplan-Meier estimates and Cox proportional hazards *** A total of 6098 younger GC patients were selected from 2000 to 2018, of which 1159 were enrolled in the China National Cancer Center, and 4939 were collected from the Surveillance Epidemiology and End Results database. Compared with the United States group, younger patients in China revealed better survival outcomes(P < 0.01). For race/ethnicity, younger Chinese cases also enjoyed a better prognosis than that in White and Black datasets(P < 0.01). After stratification by pathological Tumor-Node-Metastasis(pTNM) stage, a survival advantage was observed in China with pathological stage Ⅰ, Ⅲ, and Ⅳ(all P < 0.01), whereas younger GC patients with stage Ⅱ showed no difference(P = 0.16). In multivariate analysis, predictors in China involved period of diagnosis, linitis plastica, and pTNM stage, while race, diagnostic period, sex, location, differentiation, linitis plastica, signet ring cell, pTNM stage, surgery, and chemotherapy were confirmed in the United States group. Prognostic nomograms for younger patients were established, with the area under the curve of 0.786 in the China group and of 0.842 in the United States group. Moreover, three gene expression profiles(GSE27342, GSE51105, and GSE38749) were enrolled in further biological analysis, and distinctive molecular characteristics were identified in younger GC patients among different regions.C

关键词： Gastric cancer Younger patients Racial disparity Regional disparity Prediction model Biological analysis

Molecular cloning and characterization of the putative Halloween gene Phantom from the small brown planthopper Laodelphax striatellus

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Insect Science 2015年第6期22卷 707-718页

作者： Shuang Jia Pin-Jun wan Guo-qing Li Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests College of Plant Protection Nanjing AgriculturalUniversity Nanjing 210095 China

Ecdysteroid hormone 20-hydroxyecdysone plays fundamental roles in in- sect postembryonic development and reproduction. Several cytochrome P450 mono- oxygenases （CYPs）, encoded by the Halloween genes, have been documented to be involved in ecdysteroidogenesis in representative insects in Diptera, Lepidoptera and Orthoptera. Here the putative Halloween gene Phantom （Phm, cyp306al） from a hemipteran insect species, the small brown planthopper Laodelphax striatellus, was cloned. LsPHM shows five insect conserved P450 motifs, that is, Helix-C, Helix-I, Helix-K, PERF and heme- binding motifs. Temporal and spatial expression patterns of LsPhm were evaluated by quantitative polymerase chain reaction. Through the fourth-instar and the early fifth-instar stages, LsPhm showed two expression peaks in day 2 and days 4-5 fourth-instar nymphs, and three troughs in day 1 and 3 fourth instars and day 1 fifth instars. On day 5 of the fourth-instar nymphs, LsPhm clearly had a high transcript level in the thorax where the prothoracic glands were located. Dietary introduction of double-stranded RNA （dsRNA） of LsPhm at the nymph stage successfully knocked down the target gene, decreased expres- sion level ofecdysone receptor （LsEcR） gene and caused a higher nymphal mortality rate and delayed development. Ingestion of 20-hydroxyecdysone on LsPhm-dsRNA-exposed nymphs did not increase LsPhm expression level, but almost completely rescued the LsEcR mRNA level, and relieved the negative effects on survival and development. Thus, our data suggest that the putative LsPhm encodes a ftmctional 25-hydroxylase that catalyzes the biosynthesis of ecdysteroids in L. striatellus.

关键词： double-stranded RNA ecdysteroidogenesis Laodelphax striatellus perfor-mance Phantom

Communication-based positioning systems:past,present and prospects

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Research in Astronomy and Astrophysics 2012年第6期12卷 601-624页

作者： Guan-Yi Ma qing-Tao wan Tong Gan National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China guanyima @ nao. *** Graduate University of Chinese Academy of Sciences Beijing 100049 China

This paper reviews positioning systems in the context of communication systems. First, the basic positioning technique is described for location based ser- vice （LBS） in mobile communication systems. Then the high integrity global posi- tioning system （iGPS） is introduced in terms of aspects of what it is and how the low Earth orbit （LEO） Iridium telecommunication satellites enhance the global posi- tioning system （GPS）. Emphasis is on the Chinese Area Positioning System （CAPS） which is mainly based on commercial geostationary （GEO） communication satellites, including decommissioned GEO and inclined geosynchronous communication satel- lites. Characterized by its low cost, high flexibility, wide-area coverage and ample frequency resources, a distinctive feature of CAPS is that its navigation messages are generated on the ground, then uploaded to and forwarded by the communication satellites. Fundamental principles and key technologies applied in the construction of CAPS are presented in detail from the CAPS validation phase to its experimental system setup. A prospective view of CAPS has concluded it to be a seamless, high ac- curacy, large capacity navigation and communication system which can be achieved by expanding it world wide and enhancing it with LEO satellites and mobile base stations. Hence, this system is a potential candidate for the next generation of radio navigation after GPS.

关键词： satellite navigation -- communication -- mobile positioning -- CAPS-- iGPS -- LBS

Fault Detection for a Class of Impulsive Switched Systems

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International Journal of Automation and computing 2014年第2期11卷 223-230页

作者： qing-Yu Su Yan-Cheng Li Xing-ze Dai Jian Li School of Automation Engineering Northeast Dianli University

The problem of fault detection for a class of nonlinear impulsive switched systems is investigated in this paper. Fault detection filters are designed such that the augmented systems are stable, and the residual error signal generated by the filters guarantees the H∞ performance for disturbances and faults. Sufficient conditions for the design of fault detection(FD) filters are presented by linear matrix inequalities. Moreover, the filter gains are characterized according to a solution of a convex optimization. Finally, an example derived from a pulse-width-modulation-driven boost converter is given to illustrate the effectiveness of the FD design approach.

关键词： Impulsive switched systems fault detection(FD) H∞ performance dwell time filter design.

Energy Loss and Straggling of ^(4)He Ions in Havar

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Chinese Physics Letters 1996年第7期13卷 520-522页

作者： LU Xi-ting JIN Chang-wen WU ze-qing XIA Zong-huang Department of Technical Physics and Institute of Heavy Ion Physics Peking UniversityBeijing 100871

The energy loss and energy straggling of ^(4)He ions in Havar foil were measured with the transmission *** present result of energy loss has good agreements with that of the previous experiment and the semi-empirical predictions,while for the energy straggling data significant deviation was found at lower energies compared with the predictions of Bohr theory.

关键词： theory geometry deviation

Studies on the Catalytic Properties of Magnesia Supported on γ-Alumina

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Chemical Research in Chinese Universities 2002年第2期18卷 196-199页

作者： JIAO qing ze ZHAO Yun LI Xiao dan EVANS DG DUAN Xue Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029P.R.China

We have shown that MgO can be dispersed on γ Al 2O 3 with different loadings. The observed dispersion capacity of MgO on the surface of γ Al 2O 3 is higher than the theoretical monolayer dispersion value. The surface area and the maximum in the pore size distribution gradually decrease with the increase in MgO content at low loadings. The surface area and the maximum in the pore size distribution of MgO/ γ Al 2O 3 decrease more rapidly when the MgO content is large because the pores of γ Al 2O 3 become blocked. When small amounts of MgO are dispersed on the surface of γ Al 2O 3, the catalyst is very active and shows a good selectivity for the synthesis of glycol ethers.

关键词： Magnesia Alumina Dispersion Glycol ether

Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou ze-chen Du Xiao wang Hui-ling Jiang Qiang Zhou Yu-long Zhang Yu-zhe Liu Pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

Apolipoprotein E, amyloid-beta, and neuroinflammation in Alzheimer's disease

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Neuroscience Bulletin 2014年第2期30卷 317-330页

作者： Evan Dorey Nina Chang qing Yan Liu ze Yang wandong Zhang Faculty of Medicine University of Ottawa Human Health Therapeutics National Research Council of Canada Institute of Geriatrics/Beijing Hospital Ministry of Health of China

Alzheimer＇s disease （AD） is characterized by the accumulation and deposition of amyloid-beta （Aβ） peptides in the brain. Neuroinflammation occurs in the AD brain and plays a critical role in the neurodegenerative pathology. Particularly, Aβ evokes an inflammatory response that leads to synaptic dysfunction, neuronal death, and neurodegeneration. Apolipoprotein E （ApoE） proteins are involved in cholesterol transport, Aβ binding and clearance, and synaptic functions in the brain. The ApoE4 isoform is a key risk factor for AD, while the ApoE2 isoform has a neuroprotective effect. However, studies have reached different conclusions about the roles of the isoforms; some show that both ApoE3 and ApoE4 have anti-inflammatory effects, while others show that ApoE4 causes a predisposition to inflammation or promotes an inflammatory response following lipopolysaccharide treatment. These discrepancies may result from the differences in models, cell types, experimental conditions, and inflammatory stimuli used. Further, little was known about the role of ApoE isoforms in the Aβ-induced inflammatory response and in the neuroinflammation of AD. Our recent work showed that ApoE isoforms differentially regulate and modify the Aβ-induced inflammatory response in neural cells, with ApoE2 suppressing and ApoE4 promoting the response. In this article, we review the roles, mechanisms, and interrelations among Aβ, ApoE, and neuroinflammation in AD.

关键词： ApoE Alzheimer's disease Aβ neuroinflammation