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Comparative analysis of frame strength standards for intelligent urban rail vehicles
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作者 Li Bing Xu Hongwei Zhang Xiangjie 《China Standardization》 2025年第3期52-55,共4页
The rapid development and application of emerging information technologies,such as big data and artificial intelligence,facilitates the development of intelligent urban rail vehicles.Architecture is an important compo... The rapid development and application of emerging information technologies,such as big data and artificial intelligence,facilitates the development of intelligent urban rail vehicles.Architecture is an important component of intelligent urban rail vehicles and a key factor in ensuring their reliable and safe operation on various routes.In this context,it is very important to select appropriate architecture design standards.The paper reviews the relevant design standards for architecture at home and abroad,comprehensively analyzes the standards that need to be compared and analyzed,and conducts comprehensive comparative analysis in the aspects of the scope of application,load conditions,vertical static load,lateral load,and evaluation methods of the standards.Finally,it draws a conclusion that the standard JIS E 4207:2019,Rolling stock—Bogie—General rules for design of bogie frame strength,can meet the requirements of strength design of welded bogie frame in intelligent urban rail vehicles.It proposes the suggestions on better validating this design method in future bench and line tests of products,in order to improve the design concept of bogie frame strength and provide reference and inspiration for promoting the development of intelligent urban rail vehicles in China. 展开更多
关键词 intelligent urban rail vehicles structural strength STANDARD comparative analysis
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Comparative Analysis of Marketing Research between China and United Kingdom
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作者 Qianyu Li 《Proceedings of Business and Economic Studies》 2025年第2期326-333,共8页
This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chines... This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chinese marketing research focuses on digital transformation,policy impact,value co-creation,and emerging e-commerce models.In contrast,the UK marketing research focuses more on sustainability,technology integration,real-time research,and personalized marketing strategies.The study also found that there were few marketing articles published in Chinese and CSSCI journals in China,while the SSCI journals published in English were 62 times more than in Chinese.According to the research,digital marketing and data-driven decision-making,diversified marketing channels,sustainability and circular economy,technological innovation and cutting-edge technology application,meta-universe and blockchain technology,AI+marketing development,brand building,and international market expansion will become the research hotspots in the field of marketing in the future.The research suggests that China should strengthen the construction of an academic marketing platform,and China and the UK should strengthen cooperation in marketing research,learn from each other's strengths,and jointly give full play to their advantages in technology application,market and economy,strategy and innovation,and social media,to contribute to global economic development and marketing research. 展开更多
关键词 China and Britain Marketing research comparative analysis
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A Comparative Analysis and Implications of Research on International Chinese Language Teachers’Professional Identity from a Global Perspective
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作者 Liqiang Xu 《Journal of Contemporary Educational Research》 2025年第7期1-12,共12页
Teacher professional identity is a comprehensive reflection of teachers’role perception,emotional experiences,and behavioral tendencies towards their profession.It serves as an intrinsic driving force for teachers’p... Teacher professional identity is a comprehensive reflection of teachers’role perception,emotional experiences,and behavioral tendencies towards their profession.It serves as an intrinsic driving force for teachers’professional development and is also a crucial issue in teacher education research.From a global perspective,this study systematically reviews and examines relevant research on the professional identity of international Chinese language teachers(ICLTs).A comparative analysis is conducted between Chinese and foreign scholars’research in terms of theoretical foundations,research subjects,research content,and research methodologies.This comprehensive overview of the current research landscape in this field,along with a summary of existing achievements and identified problems,facilitates the transformation of fragmented research findings on ICLTs’professional identity into a systematic understanding and reveals research gaps.Building upon this foundation,the study proposes future research prospects for the professional identity of ICLTs from aspects such as the construction of a cross-cultural perspective-based teacher professional identity system,the transformation of teacher professional identity in the context of digital transformation,and case studies on ICLTs’professional identity.The aim is to promote high-quality development in both theory and practice of international Chinese language education. 展开更多
关键词 International Chinese language teachers Professional identity Research status Research implications comparative analysis
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Comparative Analysis of Two Heavy to Blizzard Processes in Beijing Area
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作者 Jixiong HUANG 《Meteorological and Environmental Research》 2025年第1期31-36,共6页
This paper conducted a more comprehensive review and comparative analysis of the two heavy to blizzard processes that occurred in the Beijing area during December 13-15,2023,and February 20-21,2024,in terms of compreh... This paper conducted a more comprehensive review and comparative analysis of the two heavy to blizzard processes that occurred in the Beijing area during December 13-15,2023,and February 20-21,2024,in terms of comprehensive weather situation diagnosis,forecasting,and decision-making services,and summarized the meteorological service support experience of such heavy snow weather processes.It was found that both blizzard processes were jointly influenced by the 700 hPa southwesterly warm and humid jet stream and the near-surface easterly backflow;the numerical forecast was relatively accurate in the overall description of the snowfall process,and the forecast bias of the position of the 700 hPa southwesterly warm and humid jet stream determined the bias of the snowfall magnitude forecast at a certain point;when a deviation was found between the actual snowfall and the forecast,the cause should be analyzed in a timely manner,and the warning and forecast conclusions should be updated.With the full cooperation of relevant departments,it can greatly make up for the deviation of the early forecast snowfall amount,and ensure the safety and efficiency of people's travel. 展开更多
关键词 Heavy to blizzard process Weather situation diagnosis Forecasting and decision-making services Review comparative analysis
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Decoding rural connections:A comparative insight into social network analysis in rural communities of China and beyond
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作者 Jifei Zhang Sujuan Li 《Chinese Journal of Population,Resources and Environment》 2024年第4期501-514,共14页
Social Network Theory and methods have emerged as pivotal tools for dissecting intricate interdisciplinary issues in rural communities.This study aims to systematically delineate the application characteristics and tr... Social Network Theory and methods have emerged as pivotal tools for dissecting intricate interdisciplinary issues in rural communities.This study aims to systematically delineate the application characteristics and trends of Social Network Analysis(SNA)in rural community research.Using a twofold approach,we integrate a traditional literature review and CiteSpace bibliometric analysis to assess the application status and evolutionary trends of SNA methods in this context.The key findings include the following:①Chinese research trends:scholars predominantly concentrate on the“three rural”issues(related to agriculture,rural areas,and small-scale farmers)and social support mechanisms for vulnerable rural populations.With policy shifts,rural revitalization,tourism,governance,social trust,and multi-dimensional poverty are poised to emerge as hot topics for the future.For further refinement,we suggest that the application of SNA in rural community research could benefit from content expansion,long-term studies,and innovative modelling techniques.②Research by international scholars has been primarily directed toward the physical and mental health of rural residents,as well as socioeconomic issues.Despite these studies covering a range of typical cases across various nations,a conspicuous lack of thorough,systematic,and prolonged efforts focused on rural community development in specific regions remains.Additionally,health issues affecting rural residents are expected to sustain long-standing and focused international academic attention.This study contributes to a more nuanced understanding of the current applications and potential future directions of SNA in rural community studies,both in China and internationally. 展开更多
关键词 Rural community Social network analysis(SNA) Thematic context Knowledge evolution Hot trends comparative study
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Enhancing IELTS Speaking Scores:A Comparative Analysis of High and Low Performers and Effective Strategies for Improvement
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作者 Xintong Wu 《Journal of Contemporary Educational Research》 2024年第11期317-325,共9页
This paper examines the challenges of achieving high IELTS Speaking scores,particularly due to preparation constraints and subjectivity in assessment.It contrasts speaking features of high and low scorers across four ... This paper examines the challenges of achieving high IELTS Speaking scores,particularly due to preparation constraints and subjectivity in assessment.It contrasts speaking features of high and low scorers across four key areas:fluency and coherence,lexical resource,grammatical range and accuracy,and pronunciation.The study offers strategies for improvement,focusing on topic development,vocabulary,and grammar,aiming to enhance candidates’performance. 展开更多
关键词 IELTS Speaking Assessment criteria comparative analysis Strategies for improvement
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Spatial Characteristic Analysis of the Comparative Advantage of Watermelon and Melon Production in Hainan Province 被引量:2
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作者 柳唐镜 张棵 +3 位作者 别之龙 许勇 李劲松 孔秋生 《Agricultural Science & Technology》 CAS 2013年第4期582-588,605,共8页
[Objective] This study investigated the spatial characteristics of counties (cities) with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the develo... [Objective] This study investigated the spatial characteristics of counties (cities) with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the development of watermelon and melon industries in Hainan Province. [Method] By using the sowing area, total yield, and yield per unit area of watermelon and melon in Hainan Province as research u- nits, the yield comparative advantage (YCA), efficiency comparative advantage (E- CA), scale comparative advantage (SCA), concentration ratio comparative advantage (CRCA), comprehensive comparative advantage (CCA), ratio of yield per unit area (RYPA), sowing area ratio (SAR), and distribution characteristics of watermelon and melon were systematically analyzed. By referring to the agricultural statistic data of 18 counties (cities) in Hainan Province, indexes for each research unit (i.e., the YCA index, ECA index, SCA index, CRCA index, CCA index, RYPA index, and SAR index) were established and calculated to determine the comparative advantage of watermelon and melon production in Hainan Province. A spatial expression of the research result on a map was conducted by using GIS software. [Result] Seven counties (cities) exhibited comparative advantages in watermelon production, namely, Lingshui, Wanning, Wenchang, Dongfang, Sanya, Ledong, and Changjiang. The Eastern and Southern Hainan Provinces had CCAs, and the Western and Northern Hainan Provinces could be reserved for future development. For melon production, four counties (cities) exhibited comparative advantages, namely, Ledong, Lingshui, Sanya, and Dongfang. The Southern Hainan Province had CCA, whereas the West- ern Hainan Province could be reserved for later development. [Conclusion] The result has showed that establishing watermelon and melon as dominant agricultural prod- ucts is necessary for the future development of the industry and for the formulation of a layout of regions with advantages, where key support and construction should be provided preferentially with the aim to raise the yield, quality, and market com- petitiveness of products. 展开更多
关键词 WATERMELON MELON comparative advantage Spatial analysis Hainan Province
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Comparative Analysis on Fruit Qualities of 7 Litchi Varieties from Vietnam 被引量:1
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作者 张晓芳 刘光华 +5 位作者 罗心平 黄家雄 吕玉兰 娄予强 Nguyen Dinh Tue Tran Mihn Hoa 《Agricultural Science & Technology》 CAS 2010年第8期110-113,共4页
[Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous ... [Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed. [Result] Three varieties with good general qualities including Lai Phu Ho,Thach Binh and Hung Long which were suitable to be cultivated in the local area were selected. In addition,Phu Dong was the available,early-maturing germplasm resource. [Conclusion] This research will provide reference for litchi production and breeding in northern mountainous area. 展开更多
关键词 Vietnam litchi comparative analysis of fruit qualities Variety selection
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Comparative Analysis on Fruit Qualities of Longan Varieties form Vietnam 被引量:1
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作者 张晓芳 罗心平 +4 位作者 刘光华 黄家雄 张惠云 NGUYEN Dinh Tue TRAN Mihn Hoa 《Agricultural Science & Technology》 CAS 2011年第10期1461-1463,共3页
[Objective] The aim was to screen longan varieties suitable for local production in Vietnam.[Method] The fruit botanical characteristics and quality characteristics of longan varieties introduced into Northern Mountai... [Objective] The aim was to screen longan varieties suitable for local production in Vietnam.[Method] The fruit botanical characteristics and quality characteristics of longan varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed.[Result] Two varieties with good general qualities including PMP6 and PHS1-1 which were suitable to be cultivated in the local area were selected.In addition,Phu Dong was the available processed germplasm resource.[Conclusion] This research will provide reference for longan production and breeding in Northern Mountainous. 展开更多
关键词 Vietnam longan comparative analysis of fruit qualities Variety selection
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved S1 selection method Maize population Genetic gain comparative analysis
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Mitochondrial Genomic Characterization and Phylogenetic Analysis of Wild Rapeseed Rorippa indica
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作者 Wentao Sheng 《Phyton-International Journal of Experimental Botany》 2025年第7期2015-2031,共17页
Rorippa indica is a wild oilseed crop of Brassicaceae with good environmental adaptability and strong stress resistance.This plant has become an important wild relative species for rapeseed(Brassica napus L.)and is us... Rorippa indica is a wild oilseed crop of Brassicaceae with good environmental adaptability and strong stress resistance.This plant has become an important wild relative species for rapeseed(Brassica napus L.)and is used to improve its agronomic traits,with important development and utilization value.However,the research of R.indica genetics is still lacking.And no mitochondrial genome(mitogenome)in the genus Rorippa has been expounded.To analyze the structural characteristics of the R.indica mitogenome,second-generation and third-generation sequencing techniques were made to assemble its mitogenome.The results showed that its mitogenome is composed of a single master circle DNA molecule,with 59 genes(33 protein-coding,23 tRNA,and 3 ribosomal RNA genes)annotated.The length of the circular genome is 219,775 bp,with aGCcontent of 45.24%.Themitochondrial genome contains 55 SSRs,17 tandem repeats,and 252 scattered repeat sequences,with scattered repeat sequences accounting for 77.78%.The top two codons with the highest expression levels are TTT and AUU.Moreover,377 RNA editing sites were forecasted in the R.indica mitogenome.And 22 collinear gene fragments were discriminated in the R.indica chloroplast andmitogenomes,with a total 13,153 bp length,accounting for 4.08%of the mitogenome sequence.The longest gene migration fragment is 2186 bp,and the shortest fragment is 42 bp.Furthermore,12 genes undergo complete migration between the two genomes,and 10 genes undergo partial migration.Systematic evolutionary analysis shows that R.indica and Brassica napus are grouped,indicating a close genetic relationship between the two.Herein,the R.indica mitogenome was sequenced and annotated,and it was compared with other Brassicaceae mitogenomes.A genomic data foundation was supplied for elucidating the R.indica origin and evolution. 展开更多
关键词 Rorippa indica comparative analysis MITOGENOME repeat sequence phylogenetic analysis
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Transcriptome Analysis of Derris fordii and Derris elliptica to Identify Potential Genes Involved in Rotenoid Biosynthesis
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作者 Yanlin Pan Yibin Zhang +2 位作者 Xingui Wang Hongbo Qin Lunfa Guo 《Phyton-International Journal of Experimental Botany》 2025年第1期123-136,共14页
Derris fordii and Derris elliptica belong to the Derris genus of the Fabaceae family, distinguished by their high isoflavonoid content, particularly rotenoids, which hold significance in pharmaceuticals and agricultur... Derris fordii and Derris elliptica belong to the Derris genus of the Fabaceae family, distinguished by their high isoflavonoid content, particularly rotenoids, which hold significance in pharmaceuticals and agriculture. Rotenone, as a prominent rotenoid, has a longstanding history of use in pesticides, veterinary applications, medicine, and medical research. The accumulation of rotenoids within Derris plants adheres to species-specific and tissue-specific patterns and is also influenced by environmental factors. Current research predominantly addresses extraction techniques, pharmacological applications, and pesticide formulations, whereas investigations into the biosynthesis pathway and regulatory mechanism of rotenoids remain relatively scarce. In this study, we observed notable differences in rotenone content across the roots, stems, and leaves of D. fordii, as well as within the roots of D. elliptica. Utilizing RNA sequencing (RNA-seq), we analyzed the transcriptomes and expression profiles of unigenes from these four tissues, identifying a total of 121,576 unigenes. Differentially expressed genes (DEGs) across four comparison groups demonstrated significant enrichment in the phenylpropanoid and flavonoid biosynthesis pathways. Key unigenes implicated in the rotenoid biosynthesis pathway were identified, with PAL, C4H, CHS, CHI, IFS, and HI4OMT playing critical roles in D. fordii, while IFS and HI4OMT were determined to be essential for rotenoid biosynthesis in D. elliptica. These findings enhance our understanding of the biosynthesis mechanism of rotenoids in Derris species. The unigenes identified in this study represent promising candidates for future investigations aimed at validating their roles in rotenoid biosynthesis. 展开更多
关键词 Derris fordii Derris elliptica RNA-SEQ rotenoid comparative transcriptomic analysis
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Re-evaluating drug-coated balloon use in the elderly:a need for comparative and stratified insights
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作者 Syeda Fadak Zahra Hujjat 《Journal of Geriatric Cardiology》 2025年第10期886-886,共1页
Iread with great interest the recent article by Shin,et al.[1]the authors present an important exploration into the use of drug-coated balloon(DCB)in patients aged≥75 years,a demographic increasingly encountered in m... Iread with great interest the recent article by Shin,et al.[1]the authors present an important exploration into the use of drug-coated balloon(DCB)in patients aged≥75 years,a demographic increasingly encountered in modern cardiovascular practice.The authors conducted a retrospective analysis involving 2050 elderly patients(aged≥75 years)undergoing successful percutaneous coronary intervention(PCI). 展开更多
关键词 retrospective analysis elderly percutaneous coronary intervention pci stratified insights comparative analysis percutaneous coronary intervention drug coated balloon
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A Comparative Analysis of Casual Conversation and Institutional Talk
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作者 王柯芦 《疯狂英语(教师版)》 2014年第1期139-147,共9页
This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it ... This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it reveals how the different purposes of speech result in their distinctive characteristics, and shows how language is struc- tured to construct ideational meanings(Field) and interpersonal meanings(Tenor) that define each context. 展开更多
关键词 TRANSCRIPTION comparative analysis casual CONVERSATION INSTITUTIONAL TALK
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A Comparative Analysis of the Chloroplast Genomes of Four Salvia Medicinal Plants 被引量:11
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作者 Conglian Liang Lei Wang +11 位作者 Juan Lei Baozhong Duan Weisi Ma Shuiming Xiao Haijun Qi Zhen Wang Yaoqi Liu Xiaofeng Shen Shuai Guo Haoyu Hu Jiang Xu Shilin Chen 《Engineering》 SCIE EI 2019年第5期907-915,共9页
Herbgenomics is an emerging field of traditional Chinese medicine(TCM)research and development.By combining TCM research with genomics,herbgenomics can help to establish the scientific validity of TCM and bring it int... Herbgenomics is an emerging field of traditional Chinese medicine(TCM)research and development.By combining TCM research with genomics,herbgenomics can help to establish the scientific validity of TCM and bring it into wider usage within the field of medicine.Salvia Linn.(S.Linn.)is a large genus of Labiatae that includes important medicinal plants.In this herbgenomics study,the complete chloroplast(cp)genomes of two Salvia spp.—namely,S.przewalskii and S.bulleyana,which are used as a surrogate for S.miltiorrhiza—were sequenced and compared with those of two other reported Salvia spp.—namely,S.miltiorrhiza and S.japonica.The genome organization,gene number,type,and repeat sequences were compared.The annotation results showed that both Salvia plants contain 114 unique genes,including 80 protein-coding,30 transfer RNA(tRNA),and four ribosomal RNA(rRNA)genes.Repeat sequence analysis revealed 21 forward and 22 palindromic sequences in both Salvia cp genomes,and 17 and 21 tandem repeats in S.przewalskii and S.bulleyana,respectively.A synteny comparison of the Salvia spp.cp genomes showed a high degree of sequence similarity in the coding regions and a relatively high divergence of the intergenic spacers.Pairwise alignment and single-nucleotide polymorphism(SNP)analyses found some candidate fragments to identify Salvia spp.,such as the intergenic region of the trnV–ndhC,trnQ–rps16,atpI–atpH,psbA–ycf3,ycf1,rpoC2,ndhF,matK,rpoB,rpoA,and accD genes.All of the results—including the repeat sequences and SNP sites,the inverted repeat(IR)region border,and the phylogenetic analysis—showed that S.przewalskii and S.bulleyana are extremely similar from a genetic standpoint.The cp genome sequences of the two Salvia spp.reported here will pave the way for breeding,species identification,phylogenetic evolution,and cp genetic engineering studies of Salvia medicinal plants. 展开更多
关键词 SALVIA CHLOROPLAST GENOME comparative analysis
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Comparative Analysis of Nutrient Composition of Caulerpa lentillifera from Different Regions 被引量:9
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作者 ZHANG Meijian MA Yurong +4 位作者 CHE Xinyi HUANG Zumei CHEN Peng XIA Guanghua ZHAO Meihui 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第2期439-445,共7页
This study investigated the difference of nutrient composition in Caulerpa lentillifera collected from different regions.The nutrient compositions of C.lentillifera from China's Hainan and Shandong provinces were ... This study investigated the difference of nutrient composition in Caulerpa lentillifera collected from different regions.The nutrient compositions of C.lentillifera from China's Hainan and Shandong provinces were determined and compared with those from Semporna(Malaysia),Sabah(Malaysia),Petchburi(Thailand),and two other species of seaweeds(Malaysia).The results showed that the polysaccharide and protein contents of C.lentillifera from Hainan(44.82%±0.98%and 12.5%±0.70%),Shandong(43.22%±1.42%and 14.7%±0.72%),Petchburi(59.27%±2.31%and 12.49%±0.30%),and Sabah(44.02%±2.01%and 19.38%±1.48%)were higher than those of Eucheuma cottonii(26.49%±3.01%and 9.76%±1.33%)and Sargassum polycystum(33.49%±1.70%and 5.40%±0.07%),respectively.The polyunsaturated fatty acid contents in C.lentillifera from Hainan(29.98%)and Shandong(22.11%)were higher than that in Semporna(16.76%±0.27%),Sabah(9.49%),and S.polycystum(20.34%±0.43%),but lower than that in E.cottonii(51.55%±0.57%).In Caulerpa lentillifera of Hainan and Shandong provinces,the essential amino acid(EAA)/total amino acid(TAA)ratios were 35.22%and 38.78%,respectively;and the EAA/ETAA ratios were 54.36%and 63.35%,respectively.The EAA composition of C.lentillifera was close to the ideal model of Food and Agriculture Organization/World Health Organization.C.lentillifera was rich in mineral elements,including calcium((3315.85±127.55)mg(100 g)^-1 and(3728.35±92.38)mg(100 g)^-1),magnesium((6715.74±82.58)mg(100 g)^-1 and(8128.59±242.72)mg(100 g)^-1),and trace elements,including iron((510.65±5.47)mg(100 g)^-1 and(1972.97±183.35)mg(100 g)^-1),selenium((1.04±0.08)mg(100 g)^-1 and(0.83±0.15)mg(100 g)^-1),and zinc((33.90±0.13)mg(100 g)^-1 and(11.75±2.05)mg(100 g)^-1).These results showed that C.lentillifera was more nutritious than S.polycystum or E.cottonii in terms of polysaccharide,protein,and fatty acid contents.Furthermore,both C.lentillifera species collected from Hainan and Shandong provinces show more basic nutrients.Therefore,C.lentillifera has important development and application prospects. 展开更多
关键词 Caulerpa lentillifera nutrient composition fatty acid amino acid MINERAL comparative analysis
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A Comparative Analysis of Evaporate Sediments on Earth and Mars: Implications for the Climate Change on Mars 被引量:8
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作者 ZHENG Mianping KONG Weigang +2 位作者 ZHANG Xuefei CHEN Wenxi KONG Fanjing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第3期885-897,共13页
The knowledge of Martian salts has gone through substantial changes during the past decades. In the 70th of last century, Viking landers have noticed the existence of salts on Mars. Several salt species have been sugg... The knowledge of Martian salts has gone through substantial changes during the past decades. In the 70th of last century, Viking landers have noticed the existence of salts on Mars. Several salt species have been suggested from then on, such as sulfates and chlorides. However, their origin was a mystery due to the lack of observations. The recent explorations and related studies at the beginning of this century revealed that the crustal composition of Mars is similar to that of Earth, and it was hypothesized that almost one third of Martian surface was covered by oceans and lakes in the early stage of Mars. The huge water bodies may have dissolved a large quantity of ions from Martian primary rocks during the whole Noachian and Hesperian epoch. After the enormous drought event happened during the late Hesperian and the early Amazonian, these dissolved ions have formed huge salts deposits and most of them were preserved on Mars until today. To date, carbonates, sulfates, chlorides have all been detected by orbital remote sensing and by landers and rovers. However, the salt mineral assemblages on Mars seems to have some differences from those on Earth, e.g., rich in sulfates and lack of massive carbonates. To explain this difference, we propose that most of the surface carbonates precipitated from the ancient oceans may have been dissolved by the later ubiquitous acidic fluids originated from the global volcanism in the Hesperian era, and formed the enormous sulfate deposits as detected, and this hypothesis seems to be supported by the evidence that most of the sulfate deposits distribute around the Tharsis volcanic province while the survived carbonates located far from it. This process can release most of the carbon on Mars to the atmosphere in the form of CO2 and then be erased by the late heavy bombardments, which might have profound influence on the climate change happened in the Hesperian age. The positive correlation between the GRS results of the potassium distributions and the distribution of chlorides on Mars, together with the high Br concentration measured from the evaporate sediments at two Mars exploration rover landing sites, indicate that the brines in the regions where the chlorides deposited may have reached the stage for potassium salts deposition, thus we propose for the first time that potassium salts deposits might be prevalent in these regions. 展开更多
关键词 MARS evaporate sediments comparative analysis climate change potassium salts deposition
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Comparison of R and Excel in the Field of Data Analysis
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作者 Jue Wang 《Journal of Electronic Research and Application》 2024年第3期178-184,共7页
This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and i... This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and its powerful data management and analysis tools make it suitable for handling complex data analysis tasks.It is also highly customizable,allowing users to create custom functions and packages to meet their specific needs.Additionally,R language provides high reproducibility,making it easy to replicate and verify research results,and it has excellent collaboration capabilities,enabling multiple users to work on the same project simultaneously.These advantages make R language a more suitable choice for complex data analysis tasks,particularly in scientific research and business applications.The findings of this study will help people understand that R is not just a language that can handle more data than Excel and demonstrate that r is essential to the field of data analysis.At the same time,it will also help users and organizations make informed decisions regarding their data analysis needs and software preferences. 展开更多
关键词 EXCEL R language Data analysis Open source comparE Data management Advantages Disadvantages FUNCTION
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Comparative analysis of rapamycin biosynthesis clusters between Actinoplanes sp. N902-109 and Streptomyces hygroscopicus ATCC29253 被引量:4
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作者 HUANG He REN Shuang-Xi +1 位作者 YANG Sheng HU Hai-Feng 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第2期90-98,共9页
The present study was designed to identify the difference between two rapamycin biosynthetic gene clusters from Streptomyces hygroscopicus ATCC29253 and Actinoplanes sp. N902-109 by comparing the sequence and organiza... The present study was designed to identify the difference between two rapamycin biosynthetic gene clusters from Streptomyces hygroscopicus ATCC29253 and Actinoplanes sp. N902-109 by comparing the sequence and organization of the gene clusters. The biosynthetic gene cluster for rapamycin in Streptomyces hygroscopicus ATCC29253 was reported in 1995. The second rapamycin producer, Actinoplanes sp. N902-109, which was isolated in 1995, could produce more rapamycin than Streptomyces hygroscopicus ATCC29253. The genomic map of Actinoplanes sp. N902-109 has been elucidated in our laboratory. Two gene clusters were compared using the online software anti-SMASH, Glimmer 3.02 and Subsystem Technology(RAST). Comparative analysis revealed that the organization of the multifunctional polyketide synthases(PKS) genes: Rap A, RapB, RapC, and NRPS-like RapP were identical in the two clusters. The genes responsible for precursor synthesis and macrolactone modification flanked the PKS core region in N902-109, while the homologs of those genes located downstream of the PKS core region in ATCC29253. Besides, no homolog of the gene encoding a putative type II thioesterase that may serve as a PKS "editing" enzyme accounted for over-production of rapamycin in N902-109, was found in ATCC29253. Furthermore, no homologs of genes rapQ(encoding a methyltransferase) and rap G in N902-109 were found in ATCC29253, however, an extra rap M gene encoding methyltransferase was discovered in ATCC29253. Two rapamycin biosynthetic gene clusters displayed overall high homology as well as some differences in gene organization and functions. 展开更多
关键词 RAPAMYCIN ACTINOPLANES Biosynthetic gene cluster comparative analysis
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