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Discovery of a Novel Ginseng Polysaccharide:Structure Characterization,in vitro Fermentability and Anti-oxidative Mechanism of Fermented Product via the Nrf2/HO-1 Pathway on Aβ-induced-PC 12 Cells
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作者 DONG Binbin HOU Zong +3 位作者 ZHENG Zhong XING Junpeng LIU Zhiqiang LIU Shu 《高等学校化学学报》 北大核心 2026年第1期173-189,共17页
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented... In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs. 展开更多
关键词 Ginseng polysaccharide Structural characterization Intestinal microbiota FERMENTABILITY Oxidative stress
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A Cloud-Based Distributed System for Story Visualization Using Stable Diffusion
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作者 Chuang-Chieh Lin Yung-Shen Huang Shih-Yeh Chen 《Computers, Materials & Continua》 2026年第2期1751-1769,共19页
With the rapid development of generative artificial intelligence(GenAI),the task of story visualization,which transforms natural language narratives into coherent and consistent image sequences,has attracted growing r... With the rapid development of generative artificial intelligence(GenAI),the task of story visualization,which transforms natural language narratives into coherent and consistent image sequences,has attracted growing research attention.However,existing methods still face limitations in balancing multi-frame character consistency and generation efficiency,which restricts their feasibility for large-scale practical applications.To address this issue,this study proposes a modular cloud-based distributed system built on Stable Diffusion.By separating the character generation and story generation processes,and integratingmulti-feature control techniques,a cachingmechanism,and an asynchronous task queue architecture,the system enhances generation efficiency and scalability.The experimental design includes both automated and human evaluations of character consistency,performance testing,and multinode simulation.The results show that the proposed system outperforms the baseline model StoryGen in both CLIP-I and human evaluation metrics.In terms of performance,under the experimental environment of this study,dual-node deployment reduces average waiting time by approximately 19%,while the four-node simulation further reduces it by up to 65%.Overall,this study demonstrates the advantages of cloud-distributed GenAI in maintaining character consistency and reducing generation latency,highlighting its potential value inmulti-user collaborative story visualization applications. 展开更多
关键词 Stable diffusion story visualization generativeAI distributed computing cloud-based system character consistency
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Controllable phase-reconstruction strategy for LiFePO_(4)homogeneous regeneration:Reaction mechanism,characterization and prospect
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作者 Zihao Zeng Yi Chen +4 位作者 Chao Zhu Hai Lei Wei Sun Yue Yang Peng Ge 《Journal of Energy Chemistry》 2026年第1期553-571,I0013,共20页
The growing volume of end-of-life lithium-ion batteries(LIBs)represents both an urgent environmental challenge and a critical resource opportunity,especially for cathode materials.Among commercial cathodes,LiFePO4(LFP... The growing volume of end-of-life lithium-ion batteries(LIBs)represents both an urgent environmental challenge and a critical resource opportunity,especially for cathode materials.Among commercial cathodes,LiFePO4(LFP)dominates the market due to its favorable properties;thus,a substantial amount of LFP cathode materials is expected to retire in the near future.The conventional hydrometallurgical method suffers from high costs and serious pollution.Direct regeneration technologies,especially solid-state sintering,provide a more efficient and environmentally benign alternative by repairing cathode structures through high-temperature solid-phase reactions without extra chemical reagents.Traditional solid-state sintering faces challenges in processing spent LFP from diverse sources,struggling to achieve the homogenization of physical–chemical properties and electrochemical performance.To address the limitations above,phase homogenization with a lattice reconstruction strategy has been investigated,which can enable effective lattice reconstruction and microstructural homogenization,demonstrating robust adaptability to spent samples from variable sources.This review systematically summarizes the mechanisms,detailed steps,characterization techniques,and advances in pre-oxidation optimization(including ion-doping and coated carbon layer modification),as well as future research directions for sustainable LFP recycling.Given this,this review is expected to offer theoretical guidance for achieving homogeneous regeneration of LFP cathode. 展开更多
关键词 Spent LiFePO_(4) REGENERATION Phase-reconstruction Reaction mechanism characterIZATION
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Research on characterization methods for track irregularities
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作者 Lifeng Xin Lei Xu +3 位作者 Jiaxin Zhang Menglin Pei Jianfeng Mao Dangxiong Wang 《Railway Engineering Science》 2026年第1期25-39,共15页
The characterization of track irregularities is crucial in railway dynamics,as track irregularities are the primary source of internal excitation in railway systems.In this paper,three mathematical models are proposed... The characterization of track irregularities is crucial in railway dynamics,as track irregularities are the primary source of internal excitation in railway systems.In this paper,three mathematical models are proposed to characterize the track irregularities under different circumstances.The first model is a novel explicit track spectrum function,which performs better in reflecting the inherent periodic components of track irregularities than the existing track spectra.On this foundation,the second model,a parameterized track spectrum random model,is proposed to represent the vast measured track irregularities from the probabilistic perspective.Finally,the third model,an imprecise track spectrum interval model based on a neighborhood uniform sampling Bootstrap method,is presented to identify the confidential interval of the track spectra when the track irregularity data are limited.Three examples are illustrated to demonstrate the feasibility of the three track irregularity models in characterizing the track irregularities in different conditions.This research can help capture the railway deformation status and optimize track maintenance strategies. 展开更多
关键词 RAILWAY Track irregularity Power spectral density characterIZATION Random model Imprecise track spectrum
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A comprehensive review on oxygen vacancies modified catalysts:Synthesis,characterization,and crucial role in catalytic ozonation
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作者 Fengchen Wang Yujia Xiang +9 位作者 Yuqi Zhang Xin Zhou Jing Zhang Chuanshu He Heng Zhang Zhaokun Xiong Peng Zhou Hongyu Zhou Yang Liu Bo Lai 《Chinese Chemical Letters》 2026年第2期253-262,共10页
Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for... Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for additional energy input.Enhancing catalyst activity by introducing oxygen vacancies has been used extensively in heterogeneous catalytic ozonation.This paper reviews prevalent methods for the construction and characterization of oxygen vacancies.Based on a thorough examination of existing research,the role of oxygen vacancies is categorized according to their primary mechanisms of action in heterogeneous catalytic ozonation.For example,modulation of the catalyst electronic structure to enhance electron transfer;participation in the reaction as an active site to generate radicals and non-radicals;and exposure of more metal sites to enhance the reaction.Lastly,the paper delineates the limitations and future research directions concerning the role of oxygen vacancies in catalytic ozonation.This review addresses the gap in existing literature concerning the role of oxygen vacancies in catalytic ozone systems,establishes a comprehensive theoretical framework to aid in the design of efficient ozone catalysts,and delves into the functionality of oxygen vacancies in heterogeneous catalytic ozone reactions. 展开更多
关键词 Catalytic ozonation Bulk defects Surface defects Oxygen vacancies Degradation mechanism Synthesis and characterization
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High-frequency emphasized neural network reconstruction method for in situ synchrotron radiation ultrafast computed tomography characterization
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作者 Jing-Wei Li Yu Xiao +3 位作者 Yong-Cun Li Xiao-Fang Hu Guo-Hao Du Feng Xu 《Nuclear Science and Techniques》 2026年第3期5-17,共13页
There is a contradiction between the evolution rate of materials and the time resolution of SR-CT characterization in the in situ synchrotron radiation computed tomography(SR-CT)characterization of ultrafast evolution... There is a contradiction between the evolution rate of materials and the time resolution of SR-CT characterization in the in situ synchrotron radiation computed tomography(SR-CT)characterization of ultrafast evolution process.The sampling strategy of the ultra-sparse angle is an effective method for improving time resolution.Accurate reconstruction under sparse sampling conditions has always been a bottleneck problem.In recent years,convolutional neural networks have shown outstanding advantages in sparse-angle CT reconstruction given the development of deep learning.However,existing ideas did not consider the expression of high-frequency details in neural networks,limiting their application in accurate SR-CT characterization.A novel high-frequency information-constrained deep learning network(HFIC-Net)is proposed in response to this problem.Additional high-frequency information constraints are added to improve the accuracy of the reconstruction results.Further,a series of numerical reconstruction experiments are conducted to verify this new method,and the results indicate that the reconstruction results of HFIC-Net method effectively improve reconstruction quality.This new method uses only eight-angle projections to achieve the reconstruction effect of the filtered backprojection method(FBP)method in 360 projections.The results of the HFIC-Net method demonstrate clear boundaries and accurate detailed structures,correcting the misinformation caused by using other methods.For quantitative evaluation,the SSIM used to evaluate image structure similarity is increased from 0.1951,0.9212,and 0.9308 for FBP,FBP-Conv,and DDC-Net,respectively,to 0.9620 for HFIC-Net.Finally,the results of actual SR-CT experimental data indicate that the new method can suppress artifacts and achieve accurate reconstruction,and it is suitable for the in situ SR-CT accurate characterization of ultxafast evolution process. 展开更多
关键词 Accurate SR-CT characterization CT reconstruction Sparse-angle CT reconstruction problem High-frequency information constrained Deep learning
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Hypervelocity impact response and protection for the track steels of rocket sled system via light-gas gun experiments
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作者 Siwei Zhao Yi Zeng +5 位作者 Xuewen Zhou Weixing Zhao Botao Xie Jianbin Jing Yan Chen Yilun Liu 《Defence Technology(防务技术)》 2026年第2期282-293,共12页
Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this stud... Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms. 展开更多
关键词 Hypervelocity rocket sled Gouge of the track steels Two-stage light-gas gun Microstructural characterization Coating protection
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Intelligent characterization of discontinuities and heterogeneity evaluation of potential hazard sources in high-steep rock slope by TLS-UAV technology
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作者 Changqing Liu Han Bao +5 位作者 Tianyi Wang Jingfeng Zhang Hengxing Lan Shengwen Qi Wei Yuan Shunichi Koshimura 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期509-527,共19页
The identification of rock mass hazard sources is fundamental for preventing rockfall and landslide disasters in mountainous regions,with rock mass structural characteristics playing a vital role in hazard assessment.... The identification of rock mass hazard sources is fundamental for preventing rockfall and landslide disasters in mountainous regions,with rock mass structural characteristics playing a vital role in hazard assessment.In this study,terrestrial laser scanning(TLS)and unmanned aerial vehicle(UAV)technologies were integrated to enhance the evaluation methodology for rock mass hazard sources,focusing on the Sichuan Yanjiang Expressway project in China.The findings demonstrate that TLS-UAV technology enhanced both spatial coverage and data density in slope modeling.Through integrated algorithmic analysis,rock discontinuities within heterogeneous datasets were systematically identified,enabling quantitative extraction and statistical analysis of key geometric parameters,including orientation,trace length,spacing,and roughness.Furthermore,quantitative models were developed for cohesion,friction angle and the morphology parameter M of in situ discontinuities,respectively,facilitating efficient mechanical parameter acquisition.A novel rock mass hazard index(RHI)was developed incorporating discontinuity geometric rating(DGR),discontinuity mechanical rating(DMR),and slope mass rating(SMR).Field validation confirmed the methodology's effectiveness in evaluating risk levels and spatial heterogeneity of rock mass hazard sources,revealing the contribution of different discontinuity sets to the rock mass hazard and identifying the primary discontinuity sets controlling instability mechanisms.This study is of great significance for evaluating discontinuity-controlled rock mass hazard sources and preventing rockfall disasters. 展开更多
关键词 High-steep slope Rock mass hazard source DISCONTINUITIES Intelligent characterization Terrestrial laser scanning(TLS) Unmanned aerial vehicle(UAV)
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Characterization of ceramic coating on ZK60 magnesium alloy prepared in a dual electrolyte system by micro-arc oxidation 被引量:8
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作者 Ze-Xin Wang Wei-Gang Lv +1 位作者 Jing Chen Sheng Lu 《Rare Metals》 SCIE EI CAS CSCD 2013年第5期459-464,共6页
Micro-arc oxidation (MAO) process was cartied out in an optimized dual electrolyte system to fabricate a compact, smooth, and corrosion resistant coating on ZK60 Mg alloy. The microstructural characteristics of coat... Micro-arc oxidation (MAO) process was cartied out in an optimized dual electrolyte system to fabricate a compact, smooth, and corrosion resistant coating on ZK60 Mg alloy. The microstructural characteristics of coating were investigated by scanning electron microscopy (SEM) coupled with an energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Test of mass loss was conducted at a 3.5 % NaCl solution to assess the resistance to corrosion. The bonding strength between the coating and ZK60 substrate was evaluated using scratch experiment. The results reveal that MgA1204 and MgO are the main phases of ceramic coating obtained in the dual electrolyte system. The corrosion rate of coating prepared in the optimized dual electrolyte is only 0.0061 g.m-2.h-1, which demonstrates excellent corrosion resistance. This is mainly due to the compact, uniform coating with high bonding strength. 展开更多
关键词 ZK60 magnesium alloys Micro-arc oxidation characterIZATION Dual electrolyte system
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Effect of Nano-anatase TiO_2 on Spectral Characterization of PhotosystemⅡParticles from Spinach 被引量:11
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作者 HONGFa-shui YANGPing +4 位作者 GAOFeng-qing LIUChao ZHENGLei YANGFan ZHOUJuan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第2期196-200,共5页
The photosystem Ⅱ(PSⅡ) particles were purified by means of nano-anatase TiO_2 treatment of spinach and studied by spectroscopy. The results show that the electron transport and the oxygen-evolving rate of PSⅡ are a... The photosystem Ⅱ(PSⅡ) particles were purified by means of nano-anatase TiO_2 treatment of spinach and studied by spectroscopy. The results show that the electron transport and the oxygen-evolving rate of PSⅡ are accelerated after it has been treated with nano-anatase TiO_2; the UV-Vis absorption spectrum of PSⅡ particles is increased; the red shift of fluorescence emission peak of PSⅡ is 2 nm; the peak intensity is decreased; the PSⅡ signal Ⅱs of low temperature electron paramagnetic resonanace(EPR) spectrum is intensified under light, and the PSⅡ circular dichroism(CD) spectrum is similar to that of control. It is suggested that nano-anatase TiO_2 might bind to the PSⅡ reaction center complex and intensify the function of the PSⅡ electron donor, however, nano-anatase TiO_2 treatment does not change the configuration of the PSⅡ reaction center complex. 展开更多
关键词 Nano-anatase TiO_2 SPINACH Photosystem Spectral characterization
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STUDY FOR THE BIFURCATION TOPOLOGICAL STRUCTURE AND THE GLOBAL COMPLICATED CHARACTER OF A KIND OF NONLINEAR FINANCE SYSTEM(Ⅰ) 被引量:5
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作者 MA Jun-hai(马军海) +1 位作者 CHEN Yu-shu(陈予恕) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第11期1240-1251,共12页
Based on the work discussed on the former study, this article first starts from the mathematical model of a kind of complicated financial system, and analyses all possible things that the model shows in the operation ... Based on the work discussed on the former study, this article first starts from the mathematical model of a kind of complicated financial system, and analyses all possible things that the model shows in the operation of our country's macro_financial system: balance, stable periodic, fractal, Hopf_bifurcation, the relationship between parameters and Hopf_bifurcation, and chaotic motion etc. By the changes of parameters of all economic meanings, the conditions on which the complicated behaviors occur in such a financial system, and the influence of the adjustment of the macro_economic policies and adjustment of some parameter on the whole financial system behavior have been analyzed. This study will deepen people's understanding of the lever function of all kinds of financial policies. 展开更多
关键词 stable periodic BIFURCATION chaotic topological structure global complicated character finance system
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A Quantitative Method for Characterizing Transport Capability of Compound Hydrocarbon Carrier System 被引量:4
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作者 雷裕红 罗晓容 +2 位作者 张立宽 程明 宋成鹏 《Journal of Earth Science》 SCIE CAS CSCD 2013年第3期328-342,共15页
The occurrence of hydrocarbon migration in petroliferous basins depends on the balance of driving force and resistance of carriers, which restricts mostly the quantity and positions of hydrocarbon accumulation. The dr... The occurrence of hydrocarbon migration in petroliferous basins depends on the balance of driving force and resistance of carriers, which restricts mostly the quantity and positions of hydrocarbon accumulation. The driving forces of hydrocarbon migration have been quantitatively studied, whereas the migration pathways and carriers were only qualitatively discussed up to now. Establishing a compound hydrocarbon carrier system and quantitatively characterizing its transport capability are significant for understanding the dynamic process of hydrocarbon migration and revealing the hydrocarbon accumulation characteristics. It has become an innovatory trend and also a difficult topic in study of hydrocarbon migration. In this article, a method is described for using displacement pressure to quantitatively characterize the transport capability of the compound carrier system, which composed of sandstone carriers, unconformities and faults. When the weathered and leached zone rarely developed, the basal conglomerate or transgressive sandstone of unconformities can be treated as part of sandstone carriers. An empirical relationship among core porosity, air permeability, and the pore aperture radius corresponding to a mercury saturation of 10% (r 10 ) can be obtained by multiple regression. Using porosity and permeability inversed by seismic data, the displacement pressure of sandstone carriers can be calculated by the empirical relationship and Washburn Equation. Displacement pressure of fault plane can be estimated by the regression formula between fault opening index (FOI) and hydrocarbon column height it can support. This method is applied in the eastern part of south slope in Dongying (东营) depression, Bohai (渤海) Bay Basin, China, to quantitatively characterize thetransport capability of the compound carrier system of Shahejie (沙河街) Formation. The results have good agreement with data from drilling wells. This method may be a step further in study of compound hydrocarbon carrier system in petroliferous basins. It may provide the basis of coupling expulsion quantity, migration driving force and hydrocarbon carrier system to simulate hydrocarbon migration and accumulation. Therefore this will help predict hydrocarbon migration pathways and the locations ofhydrocarbon accumulation. 展开更多
关键词 hydrocarbon carrier system quantitative characterization transport capability Dongying depression displacement pressure.
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Systematic Characterization of Long Non-Coding RNAs and Their Responses to Drought Stress in Dongxiang Wild Rice 被引量:5
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作者 QI Weidong CHEN Hongping +7 位作者 YANG Zuozhen HU Biaolin LUO Xiangdong AI Bing LUO Yuan HUANG Yu XIE Jiankun ZHANG Fantao 《Rice science》 SCIE CSCD 2020年第1期21-31,共11页
Long non-coding RNAs(lncRNAs) play important roles in response to various biotic and abiotic stresses. So far, systematic identification and characterization of lncRNAs have been reported in a few model plant species ... Long non-coding RNAs(lncRNAs) play important roles in response to various biotic and abiotic stresses. So far, systematic identification and characterization of lncRNAs have been reported in a few model plant species and major crops, but their roles in abiotic stress response have not yet been reported in common wild rice(Oryza rufipogon). Dongxiang wild rice(DXWR) possesses a high degree of drought resistance and has been well recognized as a precious genetic resource for drought resistant rice breeding. We presented the reference catalog of 1 655 novel lncRNA transcripts in DXWR using strand-specific RNA sequencing and bioinformatics approaches. Meanwhile, a total of 1092 lncRNAs were determined as differentially expressed lncRNAs under drought stress. Quantitative real-time PCR results exhibited a high concordance with RNA sequencing data, which confirmed that the expression patterns of lncRNAs based on RNA sequencing were highly reliable. Furthermore, 8 711 transcripts were predicted as target genes of the differentially expressed lncRNAs. Functional annotation analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases showed that the target genes were significantly enriched in cellular and metabolic processes, cell part, binding and plant hormone signal transduction, as well as many other terms related to abiotic stress resistance. These results expanded our understanding of lncRNA biology and provided candidate regulators for genetic improvement of drought resistance in rice cultivars. 展开更多
关键词 Dongxiang wild rice drought stress long non-coding RNA systematic characterization
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Colonic lesion characterization in inflammatory bowel disease:A systematic review and meta-analysis 被引量:4
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作者 Richard Lord Nicholas E Burr +1 位作者 Noor Mohammed Venkataraman Subramanian 《World Journal of Gastroenterology》 SCIE CAS 2018年第10期1167-1180,共14页
AIM To perform a systematic review and meta-analysis for the diagnostic accuracy of in vivo lesion characterization in colonic inflammatory bowel disease(IBD), using optical imaging techniques, including virtual chrom... AIM To perform a systematic review and meta-analysis for the diagnostic accuracy of in vivo lesion characterization in colonic inflammatory bowel disease(IBD), using optical imaging techniques, including virtual chromoendoscopy(VCE), dye-based chromoendoscopy(DBC), magnification endoscopy and confocal laser endomicroscopy(CLE). METHODS We searched Medline, Embase and the Cochrane library. We performed a bivariate meta-analysis to calculate the pooled estimate sensitivities, specificities, positive and negative likelihood ratios(+LHR,-LHR), diagnostic odds ratios(DOR), and area under the SROC curve(AUSROC) for each technology group. A subgroup analysis was performed to investigate differences in real-time nonmagnified Kudo pit patterns(with VCE and DBC) and real-time CLE.RESULTS We included 22 studies [1491 patients; 4674 polyps, of which 539(11.5%) were neoplastic]. Real-time CLE had a pooled sensitivity of 91%(95%CI: 66%-98%), specificity of 97%(95%CI: 94%-98%), and an AUSROC of 0.98(95%CI: 0.97-0.99). Magnification endoscopy had a pooled sensitivity of 90%(95%CI: 77%-96%)and specificity of 87%(95%CI: 81%-91%). VCE had a pooled sensitivity of 86%(95%CI: 62%-95%) and specificity of 87%(95%CI: 72%-95%). DBC had a pooled sensitivity of 67%(95%CI: 44%-84%) and specificity of 86%(95%CI: 72%-94%). CONCLUSION Real-time CLE is a highly accurate technology for differentiating neoplastic from non-neoplastic lesions in patients with colonic IBD. However, most CLE studies were performed by single expert users within tertiary centres, potentially confounding these results. 展开更多
关键词 Inflammatory bowel disease DYSPLASIA LESION characterIZATION Confocal laser ENDOMICROSCOPY Narrow band imaging I-scan Fujinon intelligence CHROMOENDOSCOPY
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Hydrochemical characterization and irrigation suitability of the Ganges Brahmaputra River System:review and assessment 被引量:4
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作者 BISHWAKARMA Kiran WANG Guan-xing +3 位作者 ZHANG Fan ADHIKARI Subash KARKI Kabita GHIMIRE Archana 《Journal of Mountain Science》 SCIE CSCD 2022年第2期388-402,共15页
The hydrochemical characterization and irrigation suitability assessment of the GangesBrahmaputra River System(GBRS)has immense importance for the livelihoods of people and ecosystem sustainability in the region.This ... The hydrochemical characterization and irrigation suitability assessment of the GangesBrahmaputra River System(GBRS)has immense importance for the livelihoods of people and ecosystem sustainability in the region.This study aims to assess the hydrochemical characteristics and evaluate the irrigation suitability of water in the GBRS by reviewing published literature of the major tributaries.The studied rivers were categorized into two groups namely Group-1 and Group-2 considering the similarities of climatic patterns,hydrochemical attributes,and drainage characteristics.The hydrochemistry of the river water was characterized by the Piper diagram,Gibbs plot,mixing plots,and ionic ratios.Furthermore,irrigation water qualities were evaluated by electrical conductivity(EC),sodium percentage(Na%),sodium adsorption ratio(SAR),magnesium hazard(MH),and Wilcox diagram.The results indicated that the hydrochemistry of the GBRS was slightly alkaline to alkaline(7.42-8.78)in nature.The average concentrations of most of the chemical attributes showed higher in Group-1,whereas the average concentrations of K^(+) and NO_(3)^(-) were found higher in Group-2.The average concentration of the major ions followed the dominancy order Ca^(2+)>Mg^(2+)>Na^(+)>K^(+) for cations and HCO_(3)^(-)>SO_(4)^(2-)>Cl^(-)>NO_(3)^(-) for anions in both groups.Gibbs plot and mixing plot indicated that carbonate rock weathering dominates the hydrochemical process,which was further confirmed by the Piper diagram and the ionic ratios.From the analyses of irrigational water quality,almost all the rivers(except Gomti River in terms of MH and Rangit River in terms of Na%)in the GBRS were found to be suitable based on EC,SAR,Na%,MH,and Wilcox diagram.Finally,the majority of river systems in the GBRS were characterized by carbonate dominated lithology and irrigational water quality is mostly suitable for utilization.This study could be useful for water quality management in the glacial-fed Himalayan river under the context of global climate change. 展开更多
关键词 Ganges-Brahmaputra River system Hydrochemical characterization Major ions Irrigation suitability assessment
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STUDY FOR THE BIFURCATION TOPOLOGICAL STRUCTURE AND THE GLOBAL COMPLICATED CHARACTER OF A KIND OF NONLINEAR FINANCE SYSTEM(Ⅱ) 被引量:2
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作者 马军海 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第12期1375-1382,共8页
Based on the work discussed on the former study, this article first starts from the mathematical model of a kind of complicated financial system, and analyses all possible things that the model shows in the operation ... Based on the work discussed on the former study, this article first starts from the mathematical model of a kind of complicated financial system, and analyses all possible things that the model shows in the operation of our country's macro_financial system: balance, stable periodic, fractal, Hopf_bifurcation, the relationship between parameters and Hopf_bifurcation, and chaotic motion etc. By the changes of parameters of all economic meanings, the conditions on which the complicated behaviors occur in such a financial system, and the influence of the adjustment of the macro_economic policies and adjustment of some parameter on the whole financial system behavior have been analyzed. This study will deepen people's understanding of the lever function of all kinds of financial policies. 展开更多
关键词 stable periodic BIFURCATION chaotic topological structure global complicated character finance system
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Subsurface multi-physical characterization of mountain excavation and city construction in loess plateau with a fiber-optic sensing system 被引量:3
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作者 Jie Liu Bin Shi +3 位作者 Kai Gu Meng-Ya Sun Jun-Cheng Yao He-Ming Han 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2935-2946,共12页
Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the ar... Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the artificial land is essential,yet challenging.Here,we use an improved fiber-optic monitoring system for its subsurface multi-physical characterization.The system enables us to gather spatiotemporal distribution of various parameters,including strata deformation,temperature,and moisture.Yan’an New District was selected as a case study to conduct refined in-situ monitoring through a 77 m-deep borehole and a 30 m-long trench.Findings reveal that the ground settlement involves both the deformation of the filling loess and the underlying intact loess.Notably,the filling loess exhibits a stronger creep capability compared to underlying intact loess.The deformation along the profile is unevenly distributed,with a positive correlation with soil moisture.Water accumulation has been observed at the interface between the filling loess and the underlying intact loess,leading to a significant deformation.Moreover,the temperature and moisture in the filling loess have reached a new equilibrium state,with their depths influenced by atmospheric conditions measuring at 31 m and 26 m,respectively.The refined investigation allows us to identify critical layers that matter the sustainable development of newly created urban areas,and provide improved insights into the evolution mechanisms of land creation. 展开更多
关键词 Mountain excavation and city construction Fiber-optic monitoring Multi-physical characterization Compacted loess
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As-cast and extruded Mg-Zn-Ca systems for biodegradable implants:Characterization and corrosion behavior 被引量:2
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作者 Lara Moreno Endzhe Matykina +3 位作者 Kiryl A.Yasakau Carsten Blawert Raul Arrabal Marta Mohedano 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期1102-1120,共19页
The aim of the present study is to evaluate the effect of alloy processing and composition as well as the pH control and testing medium on the in vitro corrosion performance of Mg-Zn-Ca systems for biodegradable impla... The aim of the present study is to evaluate the effect of alloy processing and composition as well as the pH control and testing medium on the in vitro corrosion performance of Mg-Zn-Ca systems for biodegradable implants.The grain size and secondary phases were analyzed by optical microscopy,scanning electron microscopy,transmission electron microscopy,and X-ray diffraction.Scanning kelvin probe force microscopy(SKPFM)was used to analyze the Volta potential values of the second phases.The corrosion performance of the three alloys was evaluated by electrochemical and hydrogen evolution methods inα-MEM with and without organic species(i.e.complete and inorganicα-MEM).Two strategies were followed to evaluate the influence of the pH on the corrosion behavior:daily solution replacement and CO_(2)flow based pH control.For all the materials,the organic medium accelerates the corrosion process.Constant pH maintained by CO_(2)flow through the medium results in considerably higher corrosion rates for all alloys.The impact of pH is lesser on the as-cast alloys due to the barrier effect of the secondary phases,particularly pronounced in the Mg1Zn1Ca alloy which showed the lowest corrosion rate.The wrought Mg0.5Zn0.2Ca alloy that lacks the refined secondary phase network and exhibits high number of twins undergoes accelerated uniform corrosion under constant pH conditions. 展开更多
关键词 MgZnCa Magnesium BIOMATERIALS characterIZATION Corrosion
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Correlations between various rock mass classification/characterization systems for the Zagros tunnel-W Iran 被引量:3
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作者 Shahriar SADEGHI Ebrahim SHARIFI TESHNIZI Benyamin GHOREISHI 《Journal of Mountain Science》 SCIE CSCD 2020年第7期1790-1806,共17页
This study deals with the comparative investigation on various classification/characterization systems for sedimentary rocks in two parts,40 kmlong of the Zagros tunnel,west of Iran.The results of extensive geotechnic... This study deals with the comparative investigation on various classification/characterization systems for sedimentary rocks in two parts,40 kmlong of the Zagros tunnel,west of Iran.The results of extensive geotechnical explorations and field measurements were applied to obtain the rock mass classification/characterization systems such as Rock Mass Rating(RMR),Rock Condition Rating(RCR),Q-system(Q),Rock Mass Number(QN),Rock Mass index(RMi),Rock Structure Rating(RSR),and Geological Strength Index(GSI)for a wide range of sedimentary rocks.A set of systems inter-relationship is proposed.Some of these correlation relations such as RMR-Q,RMR-RMi,RMi-Q,RCR,GSI-GSI(Cai)are similar to the one or more relations proposed in the previous studies,however,some of them such as RSR-RMR,RSR-Q,RCR-QN and GSI-RMR are not similar to the previous works.Joint set orientation and joint set number are more important parameters that cause weak correlation coefficients where both side classifications are not similar in considering them in calculating values.So it is proposed to find relations between any pairs of systems that both of them consider or not consider these parameters.The relations are proposed for a wide range of sedimentary rocks and can be applied for similar geological environments. 展开更多
关键词 Rock mass dassification/characterization systems Zagros Tunnel Sedimentaiy rocks
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Self nano-emulsifying drug delivery system for Embelin:Design,characterization and in-vitro studies 被引量:2
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作者 Komal Parmar Jayvadan Patel Navin Sheth 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2015年第5期396-404,共9页
CThe objective of the present study was to prepare solid self-nanoemulsifying drug delivery system(S-SNEDDS)containing Capryol-90 as oil phase for the delivery of Embelin,a poorly water soluble herbal active ingredien... CThe objective of the present study was to prepare solid self-nanoemulsifying drug delivery system(S-SNEDDS)containing Capryol-90 as oil phase for the delivery of Embelin,a poorly water soluble herbal active ingredient.Box-Behnken experimental design was employed to optimise the formulation variables,X1(amount of oil;Capryol 90),X2(amount of surfactant;Acrysol EL 135)and X3(amount of co-surfactant;PEG 400).Systems were appraised for visual characteristics for self emulsifying time,globule size and drug release.Optimised liquid formulations were formulated into free flowing granules(S-SNEDDS)by adsorption on the porous materials like Aerosil 200 and Neusilin and thereby compressed into tablet.In vitro dissolution studies of SNEDDS revealed increased in the dissolution rate of the drug.FT-IR data revealed no physicochemical interaction between drug and excipients.Solid state characterization of S-SNEDDS by DSC and Powder XRD confirmed reduction in drug crystallinity which further supports the results of dissolution studies.TEM analysis exhibited spherical globules.Further,the accelerated stability studies for 6 months revealed that S-SNEDDS of Embelin are found to be stable without any significant change in physicochemical properties.Thus,the present studies demonstrated dissolution enhancement potential of porous carrier based S-SNEDDS for poorly water soluble herbal active ingredient,Embelin. 展开更多
关键词 EMBELIN SNEDDS Dissolution enhancement Box-Behnken design characterIZATION
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