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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:1
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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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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:9
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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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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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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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Comparative Analysis of Nutrient Composition of Caulerpa lentillifera from Different Regions 被引量:8
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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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Comparative analysis of chemical components between barks and leaves of Eucommia ulmoides Oliver 被引量:10
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作者 周菊峰 张泰铭 +1 位作者 陈望爱 梁逸曾 《Journal of Central South University》 SCIE EI CAS 2009年第3期371-379,共9页
The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), a... The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), alternative moving window factor analysis (AMWFA) algorithms and normalization method based on the peak areas; the flavones in the barks and leaves of Eucommia ulmoides Oliver were separated on an ODS column by gradient elution carried out with the flow phase consisting of water, methanol and phosphoric acid (0.1%), and their contents were quantitatively determined by standard curve method and diode array detection (DAD) at 362 nm. The results show that 68 and 73 compounds respectively from essential oils of the barks and leaves of Eucommia ulmoides Oliver are identified, and there are 33 mutual compounds among 108 compounds determined. The total contents of these volatile components of the two samples possess 92.9% and 97.75% of the gross of the relevant essential oils, respectively; the contents of the rutin, quercetin and kaempferol in the barks and leaves of Eucommia ulmoides Oliver are 0.016 9, 0.003 6, 0.002 1 and 0.064 4, 0.030 2, 0.010 0 mg/g, respectively, and the determination recoveries are 95.2%-106.2%. The comparative analysis shows that for the barks and leaves of Eucommia ulmoides Oliver, there are significant differences in their components of the relevant essential oils and flavones. 展开更多
关键词 couple chromatography chemometric algorithm comparative analysis essential oil FLAVONE Eucommia ulmoides Oliver
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Comparative Analysis of the Multi-Frequency Bio-impedance and Dual-energy X-ray Absorptiometry on Body Composition in Obese Subjects 被引量:5
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作者 WANG Zheng He YANG Zhong Ping +2 位作者 WANG Xi Jie DONG Yan Hui MA Jun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第1期72-75,共4页
To examine accuracy of body composition predicted by the Multi-Frequency Bioelectric Impedance Analysis (MF-BIA) compared with the Dual-energy X-ray Absorptiometry (DXA) in adults with obese. We measured body comp... To examine accuracy of body composition predicted by the Multi-Frequency Bioelectric Impedance Analysis (MF-BIA) compared with the Dual-energy X-ray Absorptiometry (DXA) in adults with obese. We measured body composition of 749 adults with obese both by the MF-BIA and DXA. The Lin's concordance correlation and the Bland-Altman plots were used to examine the consistency. The concordance correlation coefficient of %BF between the MF-BIA and DXA in men and women was 0.560, and 0.669, respectively. Compared with the DXA, the MF-BIA significantly underestimated %BF by 4.33% in men (P 〈 0.001), however overestimated %BF by 0.50% in women (P 〈 0.001). After corrected by the correction equations established in this study, the differences were significantly decreased. Therefore, the MF-BIA (TANITA MC-180) may need to be corrected in estimating body composition for adults with obese. 展开更多
关键词 comparative analysis Dual-energy X-ray Absorptiometry on Body
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Natural Heritage Value of Xinjiang Tianshan and Global Comparative Analysis 被引量:5
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作者 XU Xiaoliang YANG Zhaoping +2 位作者 Adayi Saiken Shao Rui LIU Xinyu 《Journal of Mountain Science》 SCIE CSCD 2012年第2期262-273,共12页
Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage status.This paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tiansh... Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage status.This paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tianshan according to the World Heritage criteria.Its biological,ecological and aesthetic values,which are of global importance, are documented.It is concluded that Xinjiang Tianshan meets the world heritage criteria(vii)and (ix).Xinjiang Tianshan is compared with other mountain world heritage sites,mountains in Central Asia,the Tianshan Mountains outside China,and with the protected areas of the Tianshan Mountains on the Tentative List for World Heritage Sites,so as to provide objective data for the world heritage application. 展开更多
关键词 Xinjiang Tianshan Natural Heritage Heritage characteristics Heritage values comparative analysis
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Comparative Genomic Analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites 被引量:6
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作者 JIA Qing Jun CHEN Xin Yu +4 位作者 LI De Zhou XU Juan Juan XU Zhi Gang DUAN Zhi Liang WEN Jin Sheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第10期767-772,共6页
In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV7... In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV71/Wenzhou/CHN/2014)enterovirus 71(EV71)isolates were sequenced and described.They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster). 展开更多
关键词 CHN UTR EV comparative Genomic analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites
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Comparative Transcriptome Analysis between Cytoplasmic Male-sterile Line and Its Maintainer During the Floral Bud Development of Pepper 被引量:5
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作者 Junheng Lv Zhoubin Liu +9 位作者 Yuhua Liu Lijun Ou Minghua Deng JingWang Jingshuang Song Yanqing Ma Wenchao Chen Zhuqing Zhang Xiongze Dai Xuexiao Zou 《Horticultural Plant Journal》 2020年第2期89-98,共10页
The male-sterile line has been largely used in the hybrid seed production of pepper, which can effectively improve the efficiency of hybrid seed production. However, the formation mechanism of male sterility in pepper... The male-sterile line has been largely used in the hybrid seed production of pepper, which can effectively improve the efficiency of hybrid seed production. However, the formation mechanism of male sterility in pepper remains unclear. In the present study, we compared the gene expression patterns between pepper cytoplasmic male sterile line 9704 A and its maintainer 9704 B during floral bud development using RNA sequencing technology. A total of 547 976 and 2 416 Differentially Expressed Genes(DEGs) were identified in the stage S1, S2 and S3, respectively,and more than 70% of the DEGs were down-regulated in the sterile line. Gene Ontology(GO), and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses were performed to further understand the functions of these identified DEGs. The results showed that the DEGs were mainly enriched in pathways of starch and sucrose metabolism, pentose and glucuronate interconversions. A number of genes, such as MS1, PME5, ATPB, and lots of transcription factors were found down-regulated in the sterile line, and we also identified a series of genes with large differences in expression patterns between sterile line and maintainer line. Collectively, our findings laid a foundation for further molecular breeding in pepper and provided new insights into its mechanism underlying the male sterility. 展开更多
关键词 PEPPER CAPSICUM annuum CYTOPLASMIC male STERILITY comparative transcriptome analysis DEGs
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Comparative Analysis of Extreme High Temperature Weather in the Summers of 2013 and 2003 被引量:4
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作者 ZHANG Li-Sheng XUE Jian-Jun +1 位作者 WANG Wei-Guo SUN Jin 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期132-136,共5页
The characteristics of regional high temperature(HT) weather in 2013 and 2003 and their causes were studied using daily maximum temperature data, National Center for Environmental Prediction(NCEP) reanalysis data, and... The characteristics of regional high temperature(HT) weather in 2013 and 2003 and their causes were studied using daily maximum temperature data, National Center for Environmental Prediction(NCEP) reanalysis data, and outgoing longwave radiation(OLR) data. For these two years of HT weather, there were many similar characteristics, such as their long duration, wide range, high intensity, and severe influence. However, there were also three obvious differences: firstly, in 2013, the major area where HT weather occurred was farther north than in 2003; secondly, the HT weather in South China and the southeast area of Jiangnan in 2013 lasted fewer days than in 2003, but in other areas it lasted for more days than in 2003; thirdly, the intensity of the HT weather in 2013 was also stronger in the north and weaker in the south, similar to that of the duration. A strong and stable western Pacific subtropical high(WPSH), a continental warm high, and the distribution of the warm center in the lower troposphere played important roles in the HT weather formation. Several probable causes for the differences are that the cold air was weaker, the WPSH was farther north, and the tropical convective systems were stronger in 2013 than in 2003. Finally, a preliminary cause analysis of the WPSH anomaly was presented. 展开更多
关键词 high temperature weather comparative analysis extreme event western Pacific subtropical high
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Comparative chloroplast genome analysis of medicinally important Veratrum(Melanthiaceae)in China:Insights into genomic characterization and phylogenetic relationships 被引量:2
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作者 Ying-Min Zhang Li-Jun Han +4 位作者 Cong-Wei Yang Zi-Li Yin Xing Tian Zi-Gang Qan Guo-Dong Li 《Plant Diversity》 SCIE CAS CSCD 2022年第1期70-82,共13页
Members of Veratrum are perennial herbs widely used in traditional Chinese medicine to induce vomiting,resolve blood stasis and relieve pain.However,the intrageneric classification and phylogenetic relationships withi... Members of Veratrum are perennial herbs widely used in traditional Chinese medicine to induce vomiting,resolve blood stasis and relieve pain.However,the intrageneric classification and phylogenetic relationships within Veratrum have long been controversial due to the complexity of morphological variations and lack of high-resolution molecular markers.In this study,we reevaluated the infrageneric relationships with the genus Veratrum using complete chloroplast genome sequence data.Herein,the complete cp genomes of ten species of Veratrum were newly sequenced and characterized.The complete cp genomes of ten species of Veratrum had the typical quadripartite structure,ranging from 151,597 bp to 153,711 bp in size and comprising a total of 135 genes.The structure of Veratrum cp genomes(i.e.,gene order,content,and genome components)was highly similar across species.The number of simple sequence repeats(SSRs)ranged from 63 to 7&and of long repeats ranged from 31 to 35.Eight highly divergent regions(ndhF,psbC-psbZ,psbK-psbl,rpoB-tmCjGCA,tmK_UUU-tmQ_UUG,tmS_GCU-tmG_UCC,tmT_UGU-tmL_UAA and ycfl)were identified and are potentially useful for the DNA barcoding of Veratrum.Phylogenetic analysis among 29 taxa based on cp genomes,total genes,protein-coding genes and intergenic regions strongly supported the monophyly of Veratrum.The circumscription and relationships of the infrageneric taxa of Veratrum were well-presented with great resolution.These results will facilitate the identification,taxonomy,and utilization of Veratrum plants as well as the evolutionary studies of Melanthiaceae. 展开更多
关键词 Veratrum Melanthiaceae Chloroplast genome comparative analysis PHYLOGENY
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Comparative Analysis on Farmers' Specialized Cooperatives from the Perspective of Agricultural Industry Chain 被引量:3
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作者 Guangmi LU Zaiqing ZHU 《Asian Agricultural Research》 2017年第2期6-9,11,共5页
Taking three typical farmers' specialized cooperatives in Jingyuan County of Gansu Province as example,this paper compared with the operating mode of three cooperatives and their position in the agricultural indus... Taking three typical farmers' specialized cooperatives in Jingyuan County of Gansu Province as example,this paper compared with the operating mode of three cooperatives and their position in the agricultural industry chain,and analyzed operating characteristics,problems,and similarities of three cooperatives and their functions in the agricultural industry chain.The study indicated that the farmers' specialized cooperatives can accurately find their position in the agricultural industry chain.This is helpful for raising their comprehensive competitiveness and it is very important to manage the survival and development of farmers' specialized cooperatives,which is of utmost importance to their effective operation.According to this study,the government should strengthen its support,speed up the cultivation of new-type professional farmers,while farmers' specialized cooperatives should grasp the operating characteristics,locate themselves and integrate multi-resources.These are effective measures for promoting healthy operation of farmers' specialized cooperatives. 展开更多
关键词 Farmers’ specialized cooperatives Operating mode Agricultural industry chain comparative analysis
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Structural characterization and comparative analysis of the chloroplast genome of Ginkgo biloba and other gymnosperms 被引量:2
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作者 Xiaoming Yang Tingting Zhou +4 位作者 Xiya Su Guibin Wang Xuhui Zhang Qirong Guo Fuliang Cao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期765-778,共14页
Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 1... Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution. 展开更多
关键词 Ginkgo biloba Chloroplast genome comparative analysis PHYLOGENY
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Comparative Analysis of Gene Expression in Two Muskmelon Cultivars(Cucumis melo L.) Under Salt Stress 被引量:1
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作者 WEI Shi-wei ZHANG Fu-rong +3 位作者 ZHANG Yi-dong WANG Li-min CHEN Jia-bei HUANG Dan-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2132-2140,共9页
Salinity is one of the most important abiotic stresses that adversely affects crop growth and productivity. A subtractive suppression hybridization (SSH) library were constructed from the roots of salt-sensitive Yul... Salinity is one of the most important abiotic stresses that adversely affects crop growth and productivity. A subtractive suppression hybridization (SSH) library were constructed from the roots of salt-sensitive Yulu cultivar melon seedlings under salt stress; 557 high-quality expressed sequence tags (ESTs) were randomly sequenced, with an average size of 428 bp, which assembled into 68 contigs and 315 singletons. Compared with our previous SSH library generated from the salt-tolerant Bingxuecui cultivar, the proportion of transcripts involved in metabolism, protein fate, cellular communication/signal transduction mechanisms, and cell rescue/defense were 4, 1.46, 0.94, and 0.4% higher, respectively, in the salt-tolerant cultivar than the in salt-sensitive cultivar. Quantitative real-time PCR analysis of eleven transcripts revealed temporal variations in their expression in the two cultivars under salt stress. One NAC gene (JZ477011) was heterologously expressed in yeast for functional characterization, and enhanced the sensitivity of yeast cells to high-salinity to salt stress and inhibited their growth. Information regards to their functions would aid in the understanding of response mechanisms to saline stress and in the development of molecular markers for selecting salt-tolerant melon cultivars. 展开更多
关键词 comparative analysis functional characterization gene expression salt stress SSH melon cultivars
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