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Coexistence behavior of asymmetric attractors in hyperbolic-type memristive Hopfield neural network and its application in image encryption
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作者 李晓霞 何倩倩 +2 位作者 余天意 才壮 徐桂芝 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期302-315,共14页
The neuron model has been widely employed in neural-morphic computing systems and chaotic circuits.This study aims to develop a novel circuit simulation of a three-neuron Hopfield neural network(HNN)with coupled hyper... The neuron model has been widely employed in neural-morphic computing systems and chaotic circuits.This study aims to develop a novel circuit simulation of a three-neuron Hopfield neural network(HNN)with coupled hyperbolic memristors through the modification of a single coupling connection weight.The bistable mode of the hyperbolic memristive HNN(mHNN),characterized by the coexistence of asymmetric chaos and periodic attractors,is effectively demonstrated through the utilization of conventional nonlinear analysis techniques.These techniques include bifurcation diagrams,two-parameter maximum Lyapunov exponent plots,local attractor basins,and phase trajectory diagrams.Moreover,an encryption technique for color images is devised by leveraging the mHNN model and asymmetric structural attractors.This method demonstrates significant benefits in correlation,information entropy,and resistance to differential attacks,providing strong evidence for its effectiveness in encryption.Additionally,an improved modular circuit design method is employed to create the analog equivalent circuit of the memristive HNN.The correctness of the circuit design is confirmed through Multisim simulations,which align with numerical simulations conducted in Matlab. 展开更多
关键词 hyperbolic-type memristor Hopfield neural network(HNN) asymmetric attractors image encryption
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Determination of Benzoylaconitine Compounds in the Decoctions of Aconiti Lateralis Radix Praeparata(Heishun Pieces),Trichosanthis Fructus and Their Combination
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作者 Luyao XIE xiaoxia li +7 位作者 Jing FU Jinhua liU Yaobin HUANG Xuri WEI Tingting MO Shaomian PAN lin HUANG Jiabao MA 《Medicinal Plant》 2024年第3期1-3,22,共4页
[Objectives]This study was conducted to determine the contents of benzoylmesaconine,benzoylaconitine and benzoylhypacoitine in the decoctions of Heishun pieces,Trichosanthis Fructus and their combination.[Methods]Heis... [Objectives]This study was conducted to determine the contents of benzoylmesaconine,benzoylaconitine and benzoylhypacoitine in the decoctions of Heishun pieces,Trichosanthis Fructus and their combination.[Methods]Heishun pieces,Trichosanthis Fructus and their combination were extracted for different time periods,and then grouped.HPLC was performed using an Agilent ZORBAX SB-C 18 chromatographic column(4.6 mm×250 mm,5μm)and acetonitrile-0.02 mol/L sodium dihydrogen phosphate as the mobile phase at a flow rate of 1 mL/min and a column temperature of 30℃,and the sample volume was 20μL.The detection wavelength was 230 nm.[Results]The total amounts of benzoylmesaconine,benzoylaconitine and benzoylhypacoitine in the single decoction group of Heishun pieces were all significantly different from those in the combined decoction group at corresponding time.[Conclusions]The total content of the benzoylaconitine type increased significantly after the combined decoction of Heishun pieces and Fructus Trichosanthis,which proves the scientificity of"eighteen incompatible medicaments,19 counteraction"in traditional Chinese medicine to some extent. 展开更多
关键词 Aconiti Lateralis RADIX Praeparata Trichosanthis Fructus Benzoylaconitine COMPOUND CONTENT DETERMINATION
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Native Expanding <i>Merremia boisiana</i>Is Not More Allelopathic than Its Non-Expanding Congener <i>M. vitifolia</i>in the Expanded Range in Hainan 被引量:4
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作者 Qiaoqiao Huang Yide Shen +3 位作者 xiaoxia li Zhiwei Fan Mingguang li Hanting Cheng 《American Journal of Plant Sciences》 2013年第4期774-779,共6页
Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During rang... Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During range expansion, native species also encounter many new plant competitors. Thus, allelochemicals from native expanding species may also be more novel and allelopathic than those from non-expanding species to other plant competitors in the expanded range. We test this hypothesis using the native expanding Merremia boisiana and its non-expanding congener M. vitifolia in year 2012 inthe expanded range inHainan. In petridish bioassays, we found that aqueous extracts of M. boisiana leaves were often less inhibitory or more stimulatory to seed germination and seedling growth of five vegetable species than those of M. vitifolia leaves. In pot culture, we also found that aqueous leaf extracts of the two congeners could both inhibit the growth of a naturally co-occurring plant Paederia scanden, but their effects did not differ from each other. These results indicate that while allelopathy may contribute to the competitive ability of M. boisiana, it may not act as a novel weapon explaining its success in the expanded range in Hainan. 展开更多
关键词 ALLELOPATHY Expansion Invasion Merremia boisiana NATIVE EXPANDING Species Novel Weapons
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Lieb Lattices Formed by Real Atoms on Ag(111)and Their Lattice Constant-Dependent Electronic Properties
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作者 xiaoxia li Qili li +7 位作者 Tongzhou Ji Ruige Yan Wenlin Fan Bingfeng Miao liang Sun Gong Chen Weiyi Zhang Haifeng Ding 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第5期71-75,共5页
Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice consta... Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice constants by real atoms,i.e.,Fe atoms on Ag(111),and probed their electronic properties.We obtain a surprising long-range effective electron wavefunction overlap between Fe adatoms as it exhibits a 1/r;dependence with the interatomic distance r instead of the theoretically predicted exponential one.Combining control experiments,tight-binding modeling,and Green’s function calculations,we attribute the observed long-range overlap to being enabled by the surface state.Our findings enrich the understanding of the electron wavefunction overlap and provide a convenient platform to design and explore artificial structures and future devices with real atoms. 展开更多
关键词 properties OVERLAP EXPONENTIAL
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Construction and Analysis of SSH-cDNA Library from Leaves of Susceptible Rubber Clone Resistant to Powdery Mildew Induced by BTH
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作者 Chanjuan Luo Zhiwei Fan +4 位作者 Yide Shen xiaoxia li Hanting Chang Qiaoqiao Huang lizhen liu 《American Journal of Plant Sciences》 2013年第3期528-534,共7页
To understand the mechanism of benzothiadiazole (BTH)-induced susceptible rubber clone resistance to powdery mildew on gene level, a differentially expressed cDNA library was constructed by suppression subtractive hyb... To understand the mechanism of benzothiadiazole (BTH)-induced susceptible rubber clone resistance to powdery mildew on gene level, a differentially expressed cDNA library was constructed by suppression subtractive hybridization (SSH) with rubber Reyan 7-33-97 clone. The constructed cDNA library was high integrity through detection of the critical processes of SSH, such as efficiency of adaptor connection, subtraction and conversion, as well as the type of recombinant genes. The positive rate was 99% after identification with random 400 white spots. The size of the cDNA clone inserted fragments was various but most in 400 bp - 1000 bp. There were 23 cDNA sequences matching the function of energy and basic metabolism, signal transduction, membrane and transport, secondary metabolism and so on after detection of the 42 positive clone sequences selected randomly from the cDNA library and comparison on nucleic acid sequences in Genbank. 7 ESTs were logged in Genbank and accession numbers were GW873071 and GW874604- GW874610. The results implicated that BTH could effectively induced rubber tree resistance to powdery mildew through increasing expresses of defense-related genes in leaves of rubber tree susceptible clone. It should provide a new approach for rubber disease management. 展开更多
关键词 BENZOTHIADIAZOLE ESTs HEVEA brasiliensis INDUCED Resistance Oidium heveae Suppression Subtractive Hybridization
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Quality Standard Research of Shenqi Qiangjing Granules
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作者 Jinhua liU Min HUANG +4 位作者 Jiabao MA Bin BIN xiaoxia li Jing FU Aicun TANG 《Medicinal Plant》 CAS 2023年第1期29-32,共4页
[Objectives]The paper was to establish the quality standard of Shenqi Qiangjing granules and to conduct routine inspection of granular dosage forms.[Methods]The particle size,moisture,loss on drying,dissolubility,cont... [Objectives]The paper was to establish the quality standard of Shenqi Qiangjing granules and to conduct routine inspection of granular dosage forms.[Methods]The particle size,moisture,loss on drying,dissolubility,content uniformity and microbial limit of Shenqi Qiangjing granules were detected.Radix Astragali,Herba Epimedii,Radix Dipsaci and Fructus Schisandrae Chinensis were qualitatively identified by thin layer chromatography(TLC).[Results]The particle size,moisture,loss on drying,dissolubility,content uniformity and microbial limit of Shenqi Qiangjing granules were all in line with the relevant regulations of Pharmacopoeia of the People's Republic of China(2020 edition).Radix Astragali,Herba Epimedii,Radix Dipsaci and Fructus Schisandrae Chinensis had clear fluorescent spots in TLC assay,and no such spots were found in negative control.[Conclusions]The method has the advantages of simple operation,accurate and reliable results,strong specificity and good repeatability,and can effectively control the quality of Shenqi Qiangjing granules. 展开更多
关键词 Shenqi Qiangjing granules Quality standard control TLC
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Quality Standard of Fuyang Wenshen Granules
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作者 Wei CHEN Jing FU +3 位作者 xiaoxia li Jinhua liU Jiabao MA Yueqiang HU 《Medicinal Plant》 CAS 2023年第2期43-45,共3页
[Objectives]To establish the quality standard of Fuyang Wenshen Granules and carry out the routine examination of granule type.[Methods]The particle size,water content,solubility,loading difference and microbial limit... [Objectives]To establish the quality standard of Fuyang Wenshen Granules and carry out the routine examination of granule type.[Methods]The particle size,water content,solubility,loading difference and microbial limit of Fuyang Wenshen Granules were examined,and TLC was used for qualitative identification of Astmgali Radix and Notoginseng Radix Et Rhizoma.[Results]The particle size,water content,solubility,loading difference,and microbial limit of Fuyang Wenshen Granules complied with the relevant provisions of the Pharmacopoeia of the People's Republic of China(2020).The TLC spots of Astmgali Radix and Notoginseng Radix Et Rhizoma were clearly colored,and negative had no interference.[Conclusions]The method was simple,accurate,reliable,specific and reproducible,and can effectively control the quality of Fuyang Wenshen Granules. 展开更多
关键词 Fuyang Wenshen Granules Quality control TLC
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Skin Toxicity of Wufang Babu Ointment to Zebrafish
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作者 xiaoxia li Jiabao MA +2 位作者 Jing FU Jinhua liU Xiongbin GUI 《Medicinal Plant》 2024年第2期40-42,47,共4页
[Objectives]Using wild-type AB strain of zebrafish as experimental animal,this study investigated the damaging effect of Wufang Babu Ointment on skin cells,in order to evaluate the skin toxicity of Wufang Babu Ointmen... [Objectives]Using wild-type AB strain of zebrafish as experimental animal,this study investigated the damaging effect of Wufang Babu Ointment on skin cells,in order to evaluate the skin toxicity of Wufang Babu Ointment.[Methods]Wild-type AB strain of zebrafish with an age of 2 d were taken and fed in different concentrations of Wufang Babu Ointment solution for 24 h.The number of deaths in each group of zebrafish was recorded,and the mortality rate was calculated.Using Origin 8.0 software,the maximum non lethal concentration(MNLC)was simulated.Zebrafish raised in different concentrations of Wufang Babu Ointment solution for 24 h were placed under an anatomical microscope for taking photos,to analyze and calculate the incidence of skin damage in zebrafish.Based on the statistical analysis results of this indicator,the skin toxicity of Wufang Babu Ointment was evaluated.[Results]The MNLC of Wufang Babu Ointment on zebrafish was 671μg/mL;Wufang Babu Ointment can induce skin damage at the concentrations of 224μg/mL(1/3 MNLC)and 671μg/mL(MNLC).[Conclusions]Wufang Babu Ointment had certain skin toxicity to zebrafish. 展开更多
关键词 Wufang Babu Ointment ZEBRAFISH Skin toxicity
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Research on the Path of Transition from Financial Accounting to Management Accounting Under the Background of Big Data
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作者 xiaoxia li 《Proceedings of Business and Economic Studies》 2024年第5期112-117,共6页
Driven by the wave of big data,the traditional financial accounting model faces an urgent need for transformation,as it struggles to adapt to the complex requirements of modern enterprise management.This paper aims to... Driven by the wave of big data,the traditional financial accounting model faces an urgent need for transformation,as it struggles to adapt to the complex requirements of modern enterprise management.This paper aims to explore the feasible path for transitioning enterprise financial accounting to management accounting in the context of big data.It first analyzes the limitations of financial accounting in the era of big data,then highlights the necessity of transitioning to management accounting.Following this,the paper outlines the various challenges that may arise during this transition and,based on the analysis,proposes a series of corresponding transition strategies.These strategies aim to provide theoretical support and practical guidance for enterprises seeking a smooth transition from financial accounting to management accounting. 展开更多
关键词 Big data Financial accounting Management accounting
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ReaxFF MD局部区域反应追踪与物理性质可视化分析 被引量:4
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作者 唐钰杰 郑默 +2 位作者 任春醒 李晓霞 郭力 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第10期67-77,共11页
基于ReaxFF反应力场的反应分子动力学(ReaxFF MD)模拟方法已应用于复杂反应过程如热解、氧化、催化反应等反应机理的研究而备受关注。这类过程不仅化学反应复杂、且伴随物理过程的变化,其模拟结果分析具有挑战性。国际上首个ReaxFF MD... 基于ReaxFF反应力场的反应分子动力学(ReaxFF MD)模拟方法已应用于复杂反应过程如热解、氧化、催化反应等反应机理的研究而备受关注。这类过程不仅化学反应复杂、且伴随物理过程的变化,其模拟结果分析具有挑战性。国际上首个ReaxFF MD化学反应分析及可视化工具VARxMD可在自动分析化学反应位点的基础上获得完整反应列表、反应物和生成物的动态演化、指定反应物与生成物之间的反应网络等多层次化学反应信息,并进行基于2D和3D化学结构的可视化。因VARxMD主要针对完整模拟体系进行全局化学反应信息的挖掘,缺乏针对模拟体系中指定3D局部区域内的化学反应进行追踪和物理性质分析的能力。本工作基于VARxMD对全局化学反应的分析结果和可视化方法,通过动态继承VARxMD的全局反应分析结果,从VARxMD全局反应3D可视化视图入手进行扩展,将VTK可视化框架的观察者模式与命令模式相结合,建立了模拟体系3D局部区域的选择和绘制方法,实现了3D局部区域内化学反应追踪和瞬态结构特性的分析。从模拟体系全局分析到3D局部区域分析能力的扩展已应用于煤热解反应模拟中煤颗粒孔道间的反应追踪以及含能材料热分解过程中富碳团簇形成过程中的瞬态结构表征,也有望应用于催化反应体系表界面反应分析、含能材料爆轰过程中反应热点分析,以及煤、生物质、高分子、碳氢燃料、含能材料等体系的热解与氧化反应的ReaxFF MD模拟。 展开更多
关键词 ReaxFF MD 区域反应追踪 物理性质 可视化
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Comprehensive Marine Observing Experiment Based on High-Altitude Large Unmanned Aerial Vehicle(South China Sea Experiment2020 of the “Petrel Project”) 被引量:4
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作者 Xuefen ZHANG liangxu li +11 位作者 Rongkang YANG Ran GUO Xia SUN Jianping LUO Hongbin CHEN Daxin liU Kebing TANG Wenwu PENG Xiaodong HAN Qiyun GUO xiaoxia li Xikun FEI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第4期531-537,共7页
In collaboration with 12 other institutions, the Meteorological Observation Center of the China Meteorological Administration undertook a comprehensive marine observation experiment in the South China Sea using the Yi... In collaboration with 12 other institutions, the Meteorological Observation Center of the China Meteorological Administration undertook a comprehensive marine observation experiment in the South China Sea using the Yilong-10 high-altitude large unmanned aerial vehicle(UAV). The Yilong-10 UAV carried a self-developed dropsonde system and a millimeter-wave cloud radar system. In addition, a solar-powered unmanned surface vessel and two drifting buoys were used. The experiment was further supported by an intelligent, reciprocating horizontal drifting radiosonde system that was deployed from the Sansha Meteorological Observing Station, with the intent of producing a stereoscopic observation over the South China Sea. Comprehensive three-dimensional observations were collected using the system from 31 July to2 August, 2020. This information was used to investigate the formation and development processes of Typhoon Sinlaku(2020). The data contain measurements of 21 oceanic and meteorological parameters acquired by the five devices, along with video footage from the UAV. The data proved very helpful in determining the actual location and intensity of Typhoon Sinlaku(2020). The experiment demonstrates the feasibility of using a high-altitude, large UAV to fill in the gaps between operational meteorological observations of marine areas and typhoons near China, and marks a milestone for the use of such data for analyzing the structure and impact of a typhoon in the South China Sea. It also demonstrates the potential for establishing operational UAV meteorological observing systems in the future, and the assimilation of such data into numerical weather prediction models. 展开更多
关键词 high-altitude large UAV MARINE typhoon unmanned surface vessel horizontal drifting radiosonde drifting buoy
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The effects of clay minerals and organic matter on nanoscale pores in Lower Paleozoic shale gas reservoirs, Guizhou, China 被引量:2
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作者 Yuantao Gu Quan Wan +2 位作者 Wenbin Yu xiaoxia li Zhongbin Yu 《Acta Geochimica》 EI CAS CSCD 2018年第6期791-804,共14页
In organic-rich gas shales, clay minerals and organic matter(OM) have significant influences on the origin, preservation, and production of shale gas. Because of the substantial role of nanoscale pores in the generati... In organic-rich gas shales, clay minerals and organic matter(OM) have significant influences on the origin, preservation, and production of shale gas. Because of the substantial role of nanoscale pores in the generation,storage, and seepage of shale gas, we examined the effects of clay minerals and OM on nanoscale pore distribution characteristics in Lower Paleozoic shale gas reservoirs.Using the Niutitang and Longmaxi shales as examples, we determined the effects of clay minerals and OM on pores through sedimentation experiments. Field emission–scanning electron microscopy combined with low-pressure N2 adsorption of the samples before and after sedimentation showed significant differences in pore location and pore size distribution between the Niutitang and Longmaxi shales. Nanoscale pores mostly existed in OM in the Longmaxi shale and in clay minerals or OM–clay composites in the Niutitang shale. The distribution differences were attributed largely to variability in thermal evolution and tectonic development and might account for the difference in gas-bearing capacity between the Niutitang and Longmaxi reservoirs. In the nanoscale range, mesopores accounted for 61–76% of total nanoscale pore volume.Considerably developed nanoscale pores in OM were distributed in a broad size range in the Longmaxi shale, which led to good pore connectivity and gas production.Numerous narrow pores(i.e., pores \ 20 nm) in OM–clay composites were found in the Niutitang shale, and might account for this shale's poor pore connectivity and low gas production efficiency. Enhancing the connectivity of the mesopores(especially pores \ 20 nm and those developed in OM–clay composites) might be the key to improving development of the Niutitang shale. The findings provide new insight into the formation and evolutionary mechanism of nanoscale pores developed in OM and clay minerals. 展开更多
关键词 NANOSCALE PORE CLAY MINERALS Organic matter OM-clay composites PORE distribution characteristics PORE connectivity
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Boosting Sodium Storage of Fe1?xS/MoS2 Composite via Heterointerface Engineering 被引量:2
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作者 Song Chen Shaozhuan Huang +8 位作者 Junping Hu Shuang Fan Yang Shang Mei Er Pam xiaoxia li Ye Wang Tingting Xu Yumeng Shi Hui Ying Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第4期425-438,共14页
Improving the cycling stability of metal sulfide-based anode materials at high rate is of great significance for advanced sodium ion batteries.However,the sluggish reaction kinetics is a big obstacle for the developme... Improving the cycling stability of metal sulfide-based anode materials at high rate is of great significance for advanced sodium ion batteries.However,the sluggish reaction kinetics is a big obstacle for the development of high-performance sodium storage electrodes.Herein,we have rationally engineered the heterointerface by designing the Fe1?xS/MoS2 heterostructure with abundant“ion reservoir”to endow the electrode with excellent cycling stability and rate capability,which is proved by a series of in and ex situ electrochemical investigations.Density functional theory calculations further reveal that the heterointerface greatly decreases sodium ion diffusion barrier and facilitates charge-transfer kinetics.Our present findings not only provide a deep analysis on the correlation between the structure and performance,but also draw inspiration for rational heterointerface engineering toward the next-generation high-performance energy storage devices. 展开更多
关键词 HETEROSTRUCTURE HETEROINTERFACE Diffusion barrier ION reservoir SODIUM ION battery
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Progress in the Treatment of Fungal Infections of the Central Nervous System 被引量:5
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作者 Xuemei li xiaoxia li 《国际感染病学(电子版)》 CAS 2017年第2期60-64,共5页
HThe incidence of fungal infections of the central nervous system(CNS) has gradually increased in recent years. Intracranial fungal infection can be classified as diffuse and focal infections. The clinical manifestati... HThe incidence of fungal infections of the central nervous system(CNS) has gradually increased in recent years. Intracranial fungal infection can be classified as diffuse and focal infections. The clinical manifestations of these infections include fever and cranial pressure caused by meningitis or meningoencephalitis, and focal neurological defects caused by lesions in the intracranial space. Diagnosing fungal infections of the CNS requires the comprehensive analysis of the patient's medical history, epidemiology, underlying disease, clinical manifestation, imaging manifestations, and various laboratory test results. The identification of fungal bodies or structures in brain tissue or cerebrospinal fluid specimens is the golden standard of diagnosis. The principles for the treatment of the fungal infections of the CNS are the effective control of pathogenic risk factors, use of effective antifungal drugs, and the active implementation of surgical intervention for fungal abscesses and granuloma. In the meantime, new diagnoses and treatments should be actively explored to improve the prognosis of patients. 展开更多
关键词 FUNGUS INFECTION CENTRAL nervous system TREATMENT DIAGNOSE
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Identifying candidate genes and patterns of heat-stress response in rice using a genome-wide association study and transcriptome analyses 被引量:1
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作者 Yingxue Yang Chao Zhang +16 位作者 De Zhu Huiying He Zhaoran Wei Qiaoling Yuan xiaoxia li Xu Gao Bin Zhang Hongsheng Gao Bo Wang Shuaimin Cao Tianyi Wang Yuhua li Xiaoman Yu Longbiao Guo Guanjing Hu Qian Qian lianguang Shang 《The Crop Journal》 SCIE CSCD 2022年第6期1633-1643,共11页
Because high temperatures impair rice production,it is desirable to elucidate the regulatory mechanisms involved in rice response to heat stress.The objectives of this study were to identify candidate genes and charac... Because high temperatures impair rice production,it is desirable to elucidate the regulatory mechanisms involved in rice response to heat stress.The objectives of this study were to identify candidate genes and characterize their response patterns during rice adaptation to high temperatures at the seedling stage.Ten heat-associated quantitative-trait loci were identified in a genome-wide association study.Comparison of transcript abundances in heat-sensitive and heat-tolerant rice pools under heat stress revealed approximately 400 differentially expressed genes.The expression of genes from heatsensitive accessions changed more than those from heat-tolerant accessions under heat stress.Alternative splicing(AS)events responded to heat stress in rice.The types of AS variants significant different between the heat-sensitive and heat-tolerant accessions.Expression patterns differing between the heat-sensitive and heat-tolerant accessions were identified for genes known to be involved in heat stress.We identified eleven genes associated with rice heat stress response.These genes could be pyramided to breed heat-tolerant rice accessions. 展开更多
关键词 Heat stress RICE GWAS Alternative splicing Gene pyramiding
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小学古诗词吟诵教学策略实践研究 被引量:3
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作者 李晓霞 《西北成人教育学院学报》 2019年第6期94-98,共5页
吟诵教学是介于诵读和歌唱之间的一种读书方式,也是教学方法。当下,吟诵教学是古诗词教学的方向和前景,也是大力推进国学的新举措。小学教师掌握吟诵教学策略在古诗词教学中有非常积极的意义。知晓吟诵,闻其趣;认识吟诵,知其难;理解吟诵... 吟诵教学是介于诵读和歌唱之间的一种读书方式,也是教学方法。当下,吟诵教学是古诗词教学的方向和前景,也是大力推进国学的新举措。小学教师掌握吟诵教学策略在古诗词教学中有非常积极的意义。知晓吟诵,闻其趣;认识吟诵,知其难;理解吟诵,品其味;学习吟诵,知其法;传承吟诵,汲其华。批判地继承和发扬吟诵教学,对学生将来的学习和发展有深远的影响。 展开更多
关键词 古诗词 吟诵教学 实践研究
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Research and Design of DTC System Based on Six-phase Asymmetrical BLDCM 被引量:3
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作者 Chunyuan Bian Guannan Zhao +1 位作者 xiaoxia li Yongkui Man 《CES Transactions on Electrical Machines and Systems》 2018年第1期123-128,共6页
In this paper,the torque ripple problem of six-phase asymmetrical brushless DC motor(BLDCM)is studied.First,the basic structure of BLDCM is introduced,and the operation principle of six-phase asymmetrical BLDCM that i... In this paper,the torque ripple problem of six-phase asymmetrical brushless DC motor(BLDCM)is studied.First,the basic structure of BLDCM is introduced,and the operation principle of six-phase asymmetrical BLDCM that is studied in the thesis is expounded.Then,the principle of direct torque control(DTC)system of BLDCM is also discussed,and the improved system is proposed,including using the torque hysteresis loop and opening current hysteresis loop,and choosing the improved voltage vector to make the PWM-ON-PWM modulation.Finally,the DTC system simulation model is built,and the system is also tested by the experiment.According to the results of experiment and simulation,the DTC system designed in this thesis can control the six-phase asymmetrical BLDCM stably and reliably,and the problem of high frequency and torque ripple is solved well. 展开更多
关键词 Six-phase asymmetrical BLDCM DTC hysteresis loop torque ripple voltage space vector
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A centromere map based on super pan-genome highlights the structure and function of rice centromeres 被引量:1
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作者 Yang Lv Congcong liu +32 位作者 xiaoxia li Yueying Wang Huiying He Wenchuang He Wu Chen Longbo Yang Xiaofan Dai Xinglan Cao Xiaoman Yu Jiajia liu Bin Zhang Hua Wei Hong Zhang Hongge Qian Chuanlin Shi Yue Leng Xiangpei liu Mingliang Guo Xianmeng Wang Zhipeng Zhang Tianyi Wang Bintao Zhang Qiang Xu Yan Cui Qianqian Zhang Qiaoling Yuan Noushin Jahan Jie Ma Xiaoming Zheng Yongfeng Zhou Qian Qian Longbiao Guo lianguang Shang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第2期196-207,共12页
Rice(Oryza sativa)is a significant crop worldwide with a genome shaped by various evolutionary factors.Rice centromeres are crucial for chromosome segregation,and contain some unreported genes.Due to the diverse and c... Rice(Oryza sativa)is a significant crop worldwide with a genome shaped by various evolutionary factors.Rice centromeres are crucial for chromosome segregation,and contain some unreported genes.Due to the diverse and complex centromere region,a comprehensive understanding of rice centromere structure and function at the population level is needed.We constructed a high-quality centromere map based on the rice super pangenome consisting of a 251-accession panel comprising both cultivated and wild species of Asian and African rice.We showed that rice centromeres have diverse satellite repeat CentO,which vary across chromosomes and subpopulations,reflecting their distinct evolutionary patterns.We also revealed that long terminal repeats(LTRs),especially young Gypsy-type LTRs,are abundant in the peripheral CentO-enriched regions and drive rice centromere expansion and evolution.Furthermore,high-quality genome assembly and complete telomere-to-telomere(T2T)reference genome enable us to obtain more centromeric genome information despite mapping and cloning of centromere genes being challenging.We investigated the association between structural variations and gene expression in the rice centromere.A centromere gene,OsMAB,which positively regulates rice tiller number,was further confirmed by expression quantitative trait loci,haplotype analysis and clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein9 methods.By revealing the new insights into the evolutionary patterns and biological roles of rice centromeres,our finding will facilitate future research on centromere biology and crop improvement. 展开更多
关键词 CENTROMERE super pan-genome CentoO satellite repeat RICE
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The Peak Current Control of Permanent Magnet Brushless DC Machine with Asymmetric Dual-Three Phases 被引量:1
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作者 Chunyuan Bian xiaoxia li Guannan Zhao 《CES Transactions on Electrical Machines and Systems》 2018年第1期129-135,共7页
The asymmetric dual-three phase BLDC motor has two sets of stator windings,in which the back EMF coefficients are different.This paper takes advantage of the asymmetric dual-three phase BLDC motor’s structural featur... The asymmetric dual-three phase BLDC motor has two sets of stator windings,in which the back EMF coefficients are different.This paper takes advantage of the asymmetric dual-three phase BLDC motor’s structural features and proposes a new method for the accelerated problem of the BLDC motor operating in the high speed and the constant electromagnetic power.The dual phase windings of the BLDC motor are integrated into the circuit in the starting stage.When the motor’s back EMF value is equal to the terminal voltage value,switch off a set of RST three phase windingswhose back EMF coefficient is bigger and make the other set of stator windingUVWwith smaller back EMF coefficient continue to operate under the rated power.As the motor rotor speed continues to increase,the electromagnetic torque remains unchanged.By using the peak current control strategy,we can deduce that the phase current of the UVW three-phase winding is twice the RSTthree-phase windingwhen the asymmetric dual-three phase BLDC motor operates at high speed and constant power. 展开更多
关键词 Asymmetric dual three phases back emf coefficient peak current control
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蚕丝丝肽嗜热栖热菌发酵液对皮肤抗炎抗衰功效的增效作用
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作者 方婷欢 郑婷 +2 位作者 蒋晴 李晓霞 唐礼荣 《日用化学工业(中英文)》 CAS 北大核心 2023年第9期1057-1064,共8页
为研究嗜热栖热菌发酵的蚕丝丝肽在皮肤抗炎抗衰功效上的增效作用,以脂多糖(LPS)诱导的角质形成细胞(HaCaT细胞)和双氧水(H2O2)诱导的成纤维细胞(HDF细胞)为研究模型,通过比色法、酶联免疫吸附(ELISA)等方法检测蚕丝丝肽、嗜热栖热菌发... 为研究嗜热栖热菌发酵的蚕丝丝肽在皮肤抗炎抗衰功效上的增效作用,以脂多糖(LPS)诱导的角质形成细胞(HaCaT细胞)和双氧水(H2O2)诱导的成纤维细胞(HDF细胞)为研究模型,通过比色法、酶联免疫吸附(ELISA)等方法检测蚕丝丝肽、嗜热栖热菌发酵液和蚕丝丝肽发酵液对细胞活力、炎症因子白介素1β(IL-1β)和白介素6(IL-6)的含量、屏障保湿相关蛋白水通道蛋白3(AQP3)和丝聚蛋白(FLG)的含量、衰老相关标志物超氧化物歧化酶(SOD)、晚期糖基化终产物(AGEs)和人1型胶原蛋白(Col-1)的含量变化的影响。结果表明,蚕丝丝肽发酵液能够显著降低IL-1β,IL-6,AGEs含量,显著促进FLG,AQP3,SOD和Col-1表达,且相较于蚕丝丝肽能更显著抑制IL-6和AGEs表达,更显著促进HDF细胞迁移和SOD合成,而相较于嗜热栖热菌发酵液能更显著降低IL-1β,IL-6和AGEs表达,更显著促进AQP3表达、HDF细胞迁移和SOD的合成,即认为蚕丝丝肽发酵液相较于单一的蚕丝丝肽和嗜热栖热菌发酵液具备抗炎、屏障保湿及抗衰功效的增效作用。 展开更多
关键词 蚕丝丝肽 嗜热栖热菌 蚕丝丝肽发酵液 抗炎 抗衰 增效
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