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In silico prospective analysis of the medicinal plants activity on the CagA oncoprotein from Helicobacter pylori
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作者 Rafaela Viana Vieira Gabrielle Caroline Peiter +2 位作者 Fabrício Freire de Melo Ana Carla Zarpelon-Schutz Kádima Nayara Teixeira 《World Journal of Clinical Oncology》 2024年第5期653-663,共11页
BACKGROUND Colonization with Helicobacter pylori(H.pylori)has a strong correlation with gastric cancer,and the virulence factor CagA is implicated in carcinogenesis.Studies have been conducted using medicinal plants w... BACKGROUND Colonization with Helicobacter pylori(H.pylori)has a strong correlation with gastric cancer,and the virulence factor CagA is implicated in carcinogenesis.Studies have been conducted using medicinal plants with the aim of eliminating the pathogen;however,the possibility of blocking H.pylori-induced cell differentiation to prevent the onset and/or progression of tumors has not been addressed.This type of study is expensive and time-consuming,requiring in vitro and/or in vivo tests,which can be solved using bioinformatics.Therefore,prospective computational analyses were conducted to assess the feasibility of interaction between phenolic compounds from medicinal plants and the CagA oncoprotein.AIM To perform a computational prospecting of the interactions between phenolic compounds from medicinal plants and the CagA oncoprotein of H.pylori.METHODS In this in silico study,the structures of the phenolic compounds(ligands)kaempferol,myricetin,quercetin,ponciretin(flavonoids),and chlorogenic acid(phenolic acid)were selected from the PubChem database.These phenolic compounds were chosen based on previous studies that suggested medicinal plants as non-drug treatments to eliminate H.pylori infection.The three-dimensional structure model of the CagA oncoprotein of H.pylori(receptor)was obtained through molecular modeling using computational tools from the I-Tasser platform,employing the threading methodology.The primary sequence of CagA was sourced from GenBank(BAK52797.1).A screening was conducted to identify binding sites in the structure of the CagA oncoprotein that could potentially interact with the ligands,utilizing the GRaSP online platform.Both the ligands and receptor were prepared for molecular docking using AutoDock Tools 4(ADT)software,and the simulations were carried out using a combination of ADT and AutoDock Vina v.1.2.0 software.Two sets of simulations were performed:One involving the central region of CagA with phenolic compounds,and another involving the carboxy-terminus region of CagA with phenolic compounds.The receptor-ligand complexes were then analyzed using PyMol and BIOVIA Discovery Studio software.RESULTS The structure model obtained for the CagA oncoprotein exhibited high quality(C-score=0.09)and was validated using parameters from the MolProbity platform.The GRaSP online platform identified 24 residues(phenylalanine and leucine)as potential binding sites on the CagA oncoprotein.Molecular docking simulations were conducted with the three-dimensional model of the CagA oncoprotein.No complexes were observed in the simulations between the carboxy-terminus region of CagA and the phenolic compounds;however,all phenolic compounds interacted with the central region of the oncoprotein.Phenolic compounds and CagA exhibited significant affinity energy(-7.9 to-9.1 kcal/mol):CagA/kaempferol formed 28 chemical bonds,CagA/myricetin formed 18 chemical bonds,CagA/quercetin formed 16 chemical bonds,CagA/ponciretin formed 13 chemical bonds,and CagA/chlorogenic acid formed 17 chemical bonds.Although none of the phenolic compounds directly bound to the amino acid residues of the K-Xn-R-X-R membrane binding motif,all of them bound to residues,mostly positively or negatively charged,located near this region.CONCLUSION In silico,the tested phenolic compounds formed stable complexes with CagA.Therefore,they could be tested in vitro and/or in vivo to validate the findings,and to assess interference in CagA/cellular target interactions and in the oncogenic differentiation of gastric cells. 展开更多
关键词 CagA oncoprotein Phenolic compounds Helicobacter pylori In silico analyses Medicinal plants Prospective analysis
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Design,preparation,application of advanced array structured materials and their action mechanism analyses for high performance lithium-sulfur batteries
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作者 Nanping Deng Xiaofan Feng +7 位作者 Yongbing Jin Zhaozhao Peng Yang Feng Ying Tian Yong Liu Lu Gao Weimin Kang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期266-303,I0007,共39页
Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely comme... Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB. 展开更多
关键词 Array structured materials Preparation methods and structural designs Action mechanism analyses Advanced Li-S batteries Excellent electrochemical performances and safety
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The need to develop tailored tools for improving the quality of thematic bibliometric analyses: Evidence from papers published in Sustainability and Scientometrics
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作者 Alvaro Cabezas-Clavijo Yusnelkis Milanés-Guisado +1 位作者 Ruben Alba-Ruiz Ángel MDelgado-Vázquez 《Journal of Data and Information Science》 CSCD 2023年第4期10-35,共26页
Purpose: The aim of this article is to explore up to seven parameters related to the methodological quality and reproducibility of thematic bibliometric research published in the two most productive journals in biblio... Purpose: The aim of this article is to explore up to seven parameters related to the methodological quality and reproducibility of thematic bibliometric research published in the two most productive journals in bibliometrics, Sustainability(a journal outside the discipline) and Scientometrics, the flagship journal in the field.Design/methodology/approach: The study identifies the need for developing tailored tools for improving the quality of thematic bibliometric analyses, and presents a framework that can guide the development of such tools. A total of 508 papers are analysed, 77% of Sustainability, and 23% published in Scientometrics, for the 2019-2021 period.Findings: An average of 2.6 shortcomings per paper was found for the whole sample, with an almost identical number of flaws in both journals. Sustainability has more flaws than Scientometrics in four of the seven parameters studied, while Scientometrics has more shortcomings in the remaining three variables.Research limitations: The first limitation of this work is that it is a study of two scientific journals, so the results cannot be directly extrapolated to the set of thematic bibliometric analyses published in journals from all fields.Practical implications: We propose the adoption of protocols, guidelines, and other similar tools, adapted to bibliometric practice, which could increase the thoroughness, transparency, and reproducibility of this type of research.Originality/value: These results show considerable room for improvement in terms of the adequate use and breakdown of methodological procedures in thematic bibliometric research, both in journals in the Information Science area and journals outside the discipline. 展开更多
关键词 Thematic bibliometric analyses SUSTAINABILITY SCIENTOMETRICS Reproducibility Methodological quality
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Analysis of postoperative ocular surface changes and intervention effect after pars plana vitrectomy in meibomian gland dysfunction dry eye patients
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作者 Bo-Shi Liu Jiao-Ting Wei +5 位作者 Ze-Tong Nie Meng Yang Shao-Fang Pang Wen-Bo Li Xiao-Rong Li Bo-Jie Hu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第5期721-729,共9页
AIM:To observe ocular surface changes after phacovitrectomy in patients with mild to moderate meibomian gland dysfunction(MGD)-type dry eye and track clinical treatment response using a Keratograph 5M and a Lipi View ... AIM:To observe ocular surface changes after phacovitrectomy in patients with mild to moderate meibomian gland dysfunction(MGD)-type dry eye and track clinical treatment response using a Keratograph 5M and a Lipi View interferometer.METHODS:Forty cases were randomized into control group A and treatment group B;the latter received meibomian gland treatment 3d before phacovitrectomy and sodium hyaluronate before and after surgery.The average non-invasive tear film break-up time(NITBUTav),first noninvasive tear film break-up time(NITBUTf),non-invasive measured tear meniscus height(NTMH),meibomian gland loss(MGL),lipid layer thickness(LLT)and partial blink rate(PBR)were measured preoperatively and 1wk,1 and 3mo postoperatively.RESULTS:The NITBUTav values of group A at 1wk(4.38±0.47),1mo(6.76±0.70),and 3mo(7.25±0.68)were significantly lower than those of group B(7.45±0.78,10.46±0.97,and 11.31±0.89;P=0.002,0.004,and 0.001,respectively).The NTMH values of group B at 1wk(0.20±0.01)and 1mo(0.22±0.01)were markedly higher than those of group A(0.15±0.01 and 0.15±0.01;P=0.008 and P<0.001,respectively);however,there was no difference at 3mo.The LLT of group B at 3mo[91.5(76.25-100.00)]significantly exceeded that of group A[65.00(54.50-91.25),P=0.017].No obvious intergroup difference was found in MGL or PBR(P>0.05).CONCLUSION:Mild to moderate MGD dry eye worsens in the short term after phacovitrectomy.Preoperative cleaning,hot compresses,and meibomian gland massage as well as preoperative and postoperative sodium hyaluronate promote the rapid recovery of tear film stability. 展开更多
关键词 meibomian gland dysfunction dry eye non-invasive ocular surface analyser pars plana vitrectomy meibomian gland massage
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Mechanical stress and deformation analyses of pressurized cylindrical shells based on a higher-order modeling
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作者 S.Mannani L.Collini M.Arefi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期24-33,共10页
In this research,mechanical stress,static strain and deformation analyses of a cylindrical pressure vessel subjected to mechanical loads are presented.The kinematic relations are developed based on higherorder sinusoi... In this research,mechanical stress,static strain and deformation analyses of a cylindrical pressure vessel subjected to mechanical loads are presented.The kinematic relations are developed based on higherorder sinusoidal shear deformation theory.Thickness stretching formulation is accounted for more accurate analysis.The total transverse deflection is divided into bending,shear and thickness stretching parts in which the third term is responsible for change of deflection along the thickness direction.The axisymmetric formulations are derived through principle of virtual work.A parametric study is presented to investigate variation of stress and strain components along the thickness and longitudinal directions.To explore effect of thickness stretching model on the static results,a comparison between the present results with the available results of literature is presented.As an important output,effect of micro-scale parameter is studied on the static stress and strain distribution. 展开更多
关键词 Principle of virtual work Thickness-stretched and shear deformable model Stress and strain analyses Cylindrical pressure vessel
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Bioinformatics analyses of differentially expressed genes associated with spinal cord injury:a microarray-based analysis in a mouse model 被引量:3
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作者 Lei Guo Jing Lv +2 位作者 Yun-Fei Huang Ding-Jun Hao Ji-Jun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第7期1262-1270,共9页
Gene spectrum analysis has shown that gene expression and signaling pathways change dramatically after spinal cord injury,which may affect the microenvironment of the damaged site.Microarray analysis provides a new op... Gene spectrum analysis has shown that gene expression and signaling pathways change dramatically after spinal cord injury,which may affect the microenvironment of the damaged site.Microarray analysis provides a new opportunity for investigating diagnosis,treatment,and prognosis of spinal cord injury.However,differentially expressed genes are not consistent among studies,and many key genes and signaling pathways have not yet been accurately studied.GSE5296 was retrieved from the Gene Expression Omnibus DataSet.Differentially expressed genes were obtained using R/Bioconductor software(expression changed at least two-fold;P < 0.05).Database for Annotation,Visualization and Integrated Discovery was used for functional annotation of differentially expressed genes and Animal Transcription Factor Database for predicting potential transcription factors.The resulting transcription regulatory protein interaction network was mapped to screen representative genes and investigate their diagnostic and therapeutic value for disease.In total,this study identified 109 genes that were upregulated and 30 that were downregulated at 0.5,4,and 24 hours,and 3,7,and 28 days after spinal cord injury.The number of downregulated genes was smaller than the number of upregulated genes at each time point.Database for Annotation,Visualization and Integrated Discovery analysis found that many inflammation-related pathways were upregulated in injured spinal cord.Additionally,expression levels of these inflammation-related genes were maintained for at least 28 days.Moreover,399 regulation modes and 77 nodes were shown in the protein-protein interaction network of upregulated differentially expressed genes.Among the 10 upregulated differentially expressed genes with the highest degrees of distribution,six genes were transcription factors.Among these transcription factors,ATF3 showed the greatest change.ATF3 was upregulated within 30 minutes,and its expression levels remained high at28 days after spinal cord injury.These key genes screened by bioinformatics tools can be used as biological markers to diagnose diseases and provide a reference for identifying therapeutic targets. 展开更多
关键词 nerve REGENERATION spinal cord injury differentially expressed GENES BIOINFORMATICS analysES Database for Annotation Visualization and Integrated Discovery analysIS inflammation Kyoto Encyclopedia of GENES and Genomes pathway MICROARRAY transcription factors neural REGENERATION
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Design, Analysis and R&D of the EAST In-Vessel Components 被引量:2
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作者 姚达毛 鲍立曼 +15 位作者 李建刚 宋云涛 陈文革 杜世俊 胡庆生 卫靖 谢韩 刘旭峰 曹磊 周自波 陈俊凌 毛心桥 王声铭 祝宁 翁佩德 万元熙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期367-372,共6页
In-vessel components are important parts of the EAST superconducting tokamak. They include the plasma facing components, passive plates, cryo-pumps, in-vessel coils, etc. The structural design, analysis and related R... In-vessel components are important parts of the EAST superconducting tokamak. They include the plasma facing components, passive plates, cryo-pumps, in-vessel coils, etc. The structural design, analysis and related R&D have been completed. The divertor is designed in an up-down symmetric configuration to accommodate both double null and single null plasma operation. Passive plates are used for plasma movement control. In-vessel coils are used for the active control of plasma vertical movements. Each cryo-pump can provide an approximately 45 m^3/s pumping rate at a pressure of 10^-1 Pa for particle exhaust. Analysis shows that, when a plasma current of 1 MA disrupts in 3 ms, the EM loads caused by the eddy current and the halo current in a vertical displacement event (VDE) will not generate an unacceptable stress on the divertor structure. The bolted divertor thermal structure with an active cooling system can sustain a load of 2 MW/m^2 up to a 60 s operation if the plasma facing surface temperature is limited to 1500 ℃. Thermal testing and structural optimization testing were conducted to demonstrate the analysis results. 展开更多
关键词 EAST superconducting tokamak in-vessel components structure design and analyses thermal analyses related R&D
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Ultrasonic Welding of Magnesium–Titanium Dissimilar Metals:A Study on Thermo-mechanical Analyses of Welding Process by Experimentation and Finite Element Method 被引量:2
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作者 Dewang Zhao Daxin Ren +3 位作者 Kunmin Zhao Pan Sun Xinglin Guo Liming Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第6期181-191,共11页
Ultrasonic welding is an effective ways to achieve a non-reactive/immiscible heterogeneous metal connection, such as the connection of magnesium alloy and titanium alloy. But the thermal mechanism of magnesium alloy/t... Ultrasonic welding is an effective ways to achieve a non-reactive/immiscible heterogeneous metal connection, such as the connection of magnesium alloy and titanium alloy. But the thermal mechanism of magnesium alloy/titanium alloy ultrasonic welding has not been defined clearly. In this paper, the experimental and the finite element analysis were adopted to study the thermal mechanism during welding. Through the test, the temperature variation law during the welding process is obtained, and the accuracy of the finite element model is verified. The microscopic analysis indicates that at the welding time of 0.5 s, the magnesium alloy in the center of the solder joint is partially melted and generates the liquid phase. Through the finite element analysis, the friction coefficient of the magnesium–titanium ultrasonic welding interface can be considered as an average constant value of 0.28. The maximum temperature at the interface can exceed 600 ℃ to reach the melting point temperature of the magnesium alloy. The plastic deformation begins after 0.35 s and occurs at the magnesium side at the center of the interface. 展开更多
关键词 Ultrasonic welding Magnesium alloys Titanium alloys Thermo-mechanical analyses Finite elementanalysis
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The Study of Contact Pressure Analyses and Prediction of Dynamic Fatigue Life for Linear Guideways System 被引量:1
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作者 Thin-Lin Horng 《Modern Mechanical Engineering》 2013年第2期69-76,共8页
The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center wi... The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center with the demand of high rigidity and heavy load. By means of the study of contact behavior between the roller/guideway and roller/slider, roller type linear guideways can improve the machining accuracy. The goal of this paper is to construct the fatigue life model of the linear guideway, with the help of the contact mechanics of rollers. In beginning, the analyses of the rigidity of a single roller compressed between guideway and slider was conducted. Then, the normal contact pressure of linear guideways was obtained by using the superposition method, and verified by the FEM software (ANSYS workbench). Finally, the bearing life theory proposed by Lundberg and Palmgren was used to describe the contact fatigue life. 展开更多
关键词 Linear ROLLER Guideways SYSTEM analysis SYSTEM Stress analysES PREDICTION of FATIGUE Life
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Development of the HL-2M digital pulse analysis system
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作者 潘银海 郑博文 +1 位作者 张伟 阴泽杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第11期93-98,共6页
A digital pulse analysis system is an important diagnostic system in nuclear physics experimental research.In response to the demand for reflecting the particle state in a nuclear physics experiment,we have designed a... A digital pulse analysis system is an important diagnostic system in nuclear physics experimental research.In response to the demand for reflecting the particle state in a nuclear physics experiment,we have designed and developed a real-time digital pulse analysis system and applied it to the digital nuclear pulse waveform discrimination of different detectors in the HL-2M tokamak.The system is based on the peripheral component interconnect extensions for instrumentation(PXI)platform,while its software was written in LABVIEW.The key technologies involved in the system implementation include digital pulse analysis technology,digital discrimination technology,pulse height analysis technology,etc.The system has been applied to the plastic scintillator detector at the Neutron Source Lab of the University of Science and Technology of China.And the experimental results indicate that the system can discriminate between neutron(n)particles and gamma(γ)particles well when used to measure the plastic scintillator detector. 展开更多
关键词 digital PULSE analysis PLASTIC scintillator DETECTOR DISCRIMINATION HEIGHT analysES
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THREE-DIMENSIONAL STATIC ANALYSES FOR FGM PLATES WITH MEDIUM COMPONENTS AND DIFFERENT NET STRUCTURES
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作者 Hongmei Cheng Zhiyuan Cao 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第2期167-174,共8页
A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from ... A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from the functionally graded material structures by the normal finite elements. In order to reflect the functionally graded distributions of materials and the microconstitutions in each macro-element, the microelement method sets up the dense microelements in every macro-element, and translates nodes to the same as the normal finite elements by the degrees of freedom of all microelemental the compatibility conditions. This microelement method can fully reflect the micro constitutions and different components of materials, and its computational elements are the same as the normal finite elements, so it is an effective numerical method for the analyses of the functionally graded material structures. The three-dimensional analyses of functionally graded plates with medium components and different micro net structures are given by using the microelement method in this paper. The differences of the stress contour in the plane of functionally graded plates with different net microstructures are especially given in this paper. 展开更多
关键词 functionally graded materials medium components different net structures three-dimensional analyses microelement method span-scale analyses
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Celiac Disease Seen with the Eyes of the Principle Component Analysis and Analyse Des Données
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作者 Cleto Corposanto Beba Molinari Susanna Neuhold 《Open Journal of Statistics》 2015年第3期211-222,共12页
This paper aims to deepen the quality of life of people with celiac disease with a focus on compliance to the diet through Principle Component Analysis and Analyse des Données. In particular, we will try to under... This paper aims to deepen the quality of life of people with celiac disease with a focus on compliance to the diet through Principle Component Analysis and Analyse des Données. In particular, we will try to understand whether these analyzes are also applicable in the context of research web2.0 carried out with web-survey. 展开更多
关键词 CELIAC Disease Web-Survey PRINCIPLE Component analysis analyse DES Données
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Analyses on Marketing Strategies of Penglai's Tourism
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作者 徐宜华 《海外英语》 2013年第7X期285-288,共4页
Although tourism marketing has made great progress in recent years,researches on it are far from enough.Current re searches on tourism marketing at home and abroad lack pertinence and mostly provide theoretical basis ... Although tourism marketing has made great progress in recent years,researches on it are far from enough.Current re searches on tourism marketing at home and abroad lack pertinence and mostly provide theoretical basis for tourism development within a wide range.The researches on tourism marketing of Penglai are few and far between.Based on previous studies and the status quo of tourism marketing strategy,the below statements tries to find out existing problems of Penglai's tourism,put for ward countermeasures and propose feasible marketing patterns suitable for its tourism development.It subsequently concludes that it can make contribution to the sustainable development of Penglai's tourism and provide other county-level tourism cities with reference for marketing tourism marketing strategies. 展开更多
关键词 Penglai TOURISM MARKETING STRATEGY analysES
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A Contrastive Genre Analysis of Chinese and American University Admission Brochures
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作者 占小海 许云柯 《海外英语》 2015年第17期239-246,共8页
This study mainly uses the move and step analysis to conduct a contrastive genre analysis on the selected 20 Chinese ad-mission brochures(CABs) and 20 American admission brochures(AABs).Differences in moves,move seque... This study mainly uses the move and step analysis to conduct a contrastive genre analysis on the selected 20 Chinese ad-mission brochures(CABs) and 20 American admission brochures(AABs).Differences in moves,move sequences and step arrange-ments have revealed themselves in this comparison.Firstly,Chinese university admission brochures cast more focus on basic infor-mation about the university,the application procedure and admission criteria,while American universities,besides offering such in-formation,also emphasize the promotional function of the admission brochures.They use appealing and creative moves to commer-cially‘sell'advantages of the university to the potential applicants.Secondly,based on Kress & van Leeuwen's visual grammarsymbolic meaning,images and colors in admission brochures are also explored and analyzed as language.For one thing,after count-ing the frequency of the four categories of images,namely portrait,campus scenery,campus life pictures and graphs,it is foundthat,compared with CABs,AABs have a highly more obvious tendency in using images.The images are used as an effective tool toincrease the sense of credibility,identity-recognition,attract reader's attention,and help understanding,making the facts and in-formation more intuitive.For another thing,the main colors used in the brochures are yet another noticeable feature.Especially inAmerican brochures,universities tend to use their‘traditional colors' in the brochure to achieve a sense of consistency.Some Chi-nese brochures also follow this promotional strategy,yet a large percentage of them do not use any recognizable colors other thanthe printed black and white.Based on these differences,suggestions are put forward from perspectives including choice of movesand steps to improve the quality of CABs,hopefully raising their acceptance in the international level. 展开更多
关键词 ADMISSION BROCHURES GENRE analysis Move/Step analy
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Analysing Delay Impact from Potential Risk Factors on Project Delivery of Oil and Gas Pipeline:A Case Study in IRAQ
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作者 LAYTH KRAIDI RAJ SHAH +1 位作者 WILFRED MATIPA FIONA BORTHWICK 《Journal of Construction Research》 2020年第2期42-55,共14页
The aim of this paper is to present the design and specifications of an integrated Delay Analysis Framework(DAF),which could be used to quantify the delay caused by the Risk Factors(RFs)in Oil and Gas Pipelines(OGPs)p... The aim of this paper is to present the design and specifications of an integrated Delay Analysis Framework(DAF),which could be used to quantify the delay caused by the Risk Factors(RFs)in Oil and Gas Pipelines(OGPs)projects in a simple and systematic way.The main inputs of the DAF are(i)the potential list of RFs in the projects and their impact levels on the projects and the estimated maximum and minimum duration of each task.Monte Carlo Simulation integrated within@Risk simulator was the key process algorithm that used to quantify the impact of delay caused by the associated RFs.The key output of the DAF is the amount of potential delay caused by RFs in the OGP project.The functionalities of the developed DAF were evaluated using a case study of newly developed OGP project,in the south of Iraq.It is found that the case study project might have delayed by 45 days if neglected the consideration of the RFs associated with the project at the construction stage.The paper concludes that identifying the associated RFs and analysing the potential delay in advance will help in reducing the construction delay and improving the effectiveness of the project delivery by taking suitable risk mitigation measures. 展开更多
关键词 Oil and gas pipelines Risk factors Risk analyses Delay analysis framework @Risk Monte carlo simulation Construction delay Time impact
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Propensity score analysis demonstrated the prognostic advantage of anatomical liver resection in hepatocellular carcinoma 被引量:13
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作者 Masayuki Ishii Toru Mizuguchi +7 位作者 Masaki Kawamoto Makoto Meguro Shigenori Ota Toshihiko Nishidate Kenji Okita Yasutohsi Kimura Thomas T Hui Koichi Hirata 《World Journal of Gastroenterology》 SCIE CAS 2014年第12期3335-3342,共8页
AIM:To compare the prognoses of hepatocellular carcinoma(HCC)patients that underwent anatomic liver resection(AR)or non-anatomic liver resection(NAR)using propensity score-matched populations.METHODS:Between January 2... AIM:To compare the prognoses of hepatocellular carcinoma(HCC)patients that underwent anatomic liver resection(AR)or non-anatomic liver resection(NAR)using propensity score-matched populations.METHODS:Between January 2002 and December2010,268 consecutive HCC patients,including 110 and158 patients that underwent AR and NAR,respectively,were retrospectively enrolled in this study.Forty-four patients from each group were selected and matched using logistic multivariate analysis followed by propensity score analysis.RESULTS:In the whole analysis set,the histological background of the liver,liver function,and tumor marker levels differed significantly among the groups.Although the overall survival(OS)and recurrence-free survival rates of the two groups did not differ significantly in the whole analysis set,the OS of the AR group was significantly longer than that of the NAR group after propensity matching(76.2±6.3 mo vs 58.9±6.3mo;P=0.0039).Although AR(HR=0.456,P=0.039)was found to be a prognostic factor in the univariate analysis,only vascular invasion(HR=0.228,P=0.002)and the hepatocyte growth factor level(HR=52.366,P=0.035)were subsequently found to be independent prognostic factors.CONCLUSION:AR conveys a survival advantage over NAR in specific subpopulations of HCC patients with tumors of less than 5 cm in diameter,single tumor,and good liver function. 展开更多
关键词 ANATOMICAL liver RESECTION PROPENSITY SCORE analys
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Determining the spatial distribution of soil properties using the environmental covariates and multivariate statistical analysis: a case study in semi-arid regions of Iran 被引量:5
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作者 Mojtaba ZERAATPISHEH Shamsollah AYOUBI +1 位作者 Magboul SULIEMAN JesusRODRIGO-COMINO 《Journal of Arid Land》 SCIE CSCD 2019年第4期551-566,共16页
Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most re... Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most relevant to predicting soil properties at the catchment scale in semi-arid areas. Thus, this research aims to investigate the ability of multivariate statistical analyses to distinguish which soil properties follow a clear spatial pattern conditioned by specific environmental characteristics in a semi-arid region of Iran. To achieve this goal, we digitized parent materials and landforms by recent orthophotography. Also, we extracted ten topographical attributes and five remote sensing variables from a digital elevation model(DEM) and the Landsat Enhanced Thematic Mapper(ETM), respectively. These factors were contrasted for 334 soil samples(depth of 0–30 cm). Cluster analysis and soil maps reveal that Cluster 1 comprises of limestones, massive limestones and mixed deposits of conglomerates with low soil organic carbon(SOC) and clay contents, and Cluster 2 is composed of soils that originated from quaternary and early quaternary parent materials such as terraces, alluvial fans, lake deposits, and marls or conglomerates that register the highest SOC content and the lowest sand and silt contents. Further, it is confirmed that soils with the highest SOC and clay contents are located in wetlands, lagoons, alluvial fans and piedmonts, while soils with the lowest SOC and clay contents are located in dissected alluvial fans, eroded hills, rock outcrops and steep hills. The results of principal component analysis using the remote sensing data and topographical attributes identify five main components, which explain 73.3% of the total variability of soil properties. Environmental factors such as hillslope morphology and all of the remote sensing variables can largely explain SOC variability, but no significant correlation is found for soil texture and calcium carbonate equivalent contents. Therefore, we conclude that SOC can be considered as the best-predicted soil property in semi-arid regions. 展开更多
关键词 soil properties remote sensing data topographical attributes MULTIVARIATE statistical analyses GEOGRAPHIC information systems land management
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Gas chromatography-mass spectrometry analysis of different organic crude extracts from the local medicinal plant of Thymus vulgaris L 被引量:4
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作者 Laila Salim Al Hashmi Mohammad Amzad Hossain +2 位作者 Afaf Mohammed Weli Qasim Al-Riyami Jamal Nasser Al-Sabahi 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第1期69-73,共5页
Objective:To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L(T.vulgaris)by gas chromatography-mass spectrometry(GC-MS).Methods:The shad... Objective:To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L(T.vulgaris)by gas chromatography-mass spectrometry(GC-MS).Methods:The shade dried leaves powder was extracted with methanol by using Soxhlet extractor.Methanol crude extracts of T.vulgaris and the derived fractions of hexane,chloroform,ethyl acetate and butanol were obtained.Results:Qualitative analyses of various organic crude extracts of T.vulgaris by using GC-MS showed that there were different types of high and low molecular weight compounds.Most of the isolated and identified compounds by GC-MS in the crude extracts are basically biologically important.Further,the T.vulgaris leaf possessed certain characteristics that can be ascribed to cultivation on a domestic plantation.The crude extracts were prepared from the powder leaves of T.vulgaris for respective compounds can be chosen on the basis of above GC-MS analysis.Conclusions:All the major compounds were identified and characterized by spectroscopic method in different organic crude extracts of T.vulgaris are biologically active molecules.Thus the identification of a good number of compounds in various crude extracts of T.vulgaris might have some ecological role. 展开更多
关键词 THYMUS VULGARIS L Preparation CRUDE extracts SOXHLET EXTRACTOR GC-MS analyses
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Development of x-ray scintillator functioning also as an analyser grating used in grating-based x-ray differential phase contrast imaging 被引量:4
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作者 雷耀虎 刘鑫 +2 位作者 郭金川 赵志刚 牛憨笨 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期222-227,共6页
In order to push the grating-based phase contrast imaging system to be used in hospitM and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating,... In order to push the grating-based phase contrast imaging system to be used in hospitM and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating, which has been proposed for grating-based x-ray differential phase contrast imaging. According to this design, the scintillator should have a periodical structure in one dimension with the pitch equaling the period of self-image of the phase grating at the Talbot distance, where one half of the pitch is pixellated and is made of x-ray sensitive fluorescent material, such as CsI(T1), and the remaining part of the pitch is made of x-ray insensitive material, such as silicon. To realize the design, a deep pore array with a high aspect ratio and specially designed grating pattern are successfully manufactured on 5 inch silicon wafer by the photo-assisted electrochemical etching method. The related other problems, such as oxidation-caused geometrical distortion, the filling of CsI(T1) into deep pores and the removal of inside bubbles, have been overcome. Its pixel size, depth and grating pitch are 3 p.m^7.5 ~m, 150 p^m and 3 Ixm, respectively. The microstructure of the scintillator has been examined microscopically and macroscopically by scanning electron microscope and x-ray resolution chart testing, respectively. The preliminary measurements have shown that the proposed scintillator, also functioning as an analyser grating, has been successfully designed and developed. 展开更多
关键词 scintillator screen pore arrays oxidation CsI(T1) analyser grating
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Increased virulence of the oral microbiome in oral squamous cell carcinoma revealed by metatranscriptome analyses 被引量:10
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作者 Susan Yost Philip Stashenko +6 位作者 Yoonhee Choi Maria Kukuruzinska Caroline A.Genco Andrew Salama Ellen O.Weinberg Carolyn D.Kramer Jorge Frias-Lopez 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第4期263-272,共10页
Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between ... Oral squamous cell carcinoma(OSCC) is the most prevalent and most commonly studied oral cancer. However, there is a void regarding the role that the oral microbiome may play in OSCC. Although the relationship between microbial community composition and OSCC has been thoroughly investigated, microbial profiles of the human microbiome in cancer are understudied. Here we performed a small pilot study of community-wide metatranscriptome analysis to profile mRNA expression in the entire oral microbiome in OSCC to reveal molecular functions associated with this disease. Fusobacteria showed a statistically significantly higher number of transcripts at tumour sites and tumour-adjacent sites of cancer patients compared to the healthy controls analysed. Regardless of the community composition, specific metabolic signatures were consistently found in disease. Activities such as iron ion transport, tryptophanase activity, peptidase activities and superoxide dismutase were over-represented in tumour and tumour-adjacent samples when compared to the healthy controls. The expression of putative virulence factors in the oral communities associated with OSCC showed that activities related to capsule biosynthesis, flagellum synthesis and assembly, chemotaxis, iron transport, haemolysins and adhesins were upregulated at tumour sites. Moreover, activities associated with protection against reactive nitrogen intermediates, chemotaxis, flagellar and capsule biosynthesis were also upregulated in non-tumour sites of cancer patients. Although they are preliminary, our results further suggest that Fusobacteria may be the leading phylogenetic group responsible for the increase in expression of virulence factors in the oral microbiome of OSCC patients. 展开更多
关键词 profiles analysES
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