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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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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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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 seismic performance analysis of steel braced frames with resilient slip-friction joint braces and buckling-restrained braces
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作者 Rajnil Lal Ashkan Hashemi +2 位作者 Nicholas Chan Setu Agarwal Pierre Quenneville 《Resilient Cities and Structures》 2025年第3期30-47,共18页
Self-centering systems are increasingly studied after devastating earthquakes in the 2010s that caused irreparable damage to buildings.Currently,there is conflicting evidence as to whether the re-centering(restoring)c... Self-centering systems are increasingly studied after devastating earthquakes in the 2010s that caused irreparable damage to buildings.Currently,there is conflicting evidence as to whether the re-centering(restoring)capabilities are gained at the expense of hysteretic damping,potentially leading to larger peak displacements and damage to non-structural elements.This study examines the earthquake response of self-centering and non-self-centering systems through analyses of 4-storey and 8-storey steel-braced frames.The Resilient Slip Friction Joint(RSFJ)dampers,combined with steel braces in series,represent the self-centering bracing system,whereas the Buckling Restrained Braces(BRBs)represent the non-self-centering bracing system.Results suggest that peak displacements,base shears,and floor accelerations were comparable between the two systems.A possible explanation is that the peak response occurs on the first major excursion;similar peaks result from similar backbone curves in the run-up to the peak.Conversely,the amount of hysteretic damping only begins to affect the post-peak behavior.For instance,the RSFJ system reintroduces seismic energy into the structure post-peak(rather than dissipating it like the BRB).Subsequently,it leads to larger vibration amplitudes about the central position,increasing the risk of secondary peaks.This contrasts with the BRB system,which exhibits smaller vibration amplitudes about an increasingly deformed position due to seismic ratcheting.Unsurprisingly,residual deformations were high for the BRBs(1.7%on average)and negligible for the RSFJ.However,RSFJ produced smaller peak inter-storey drifts between 13%–18%but higher peak accelerations by 4%–5%.The results suggest that multi-storey braced frames could be designed with similar or smaller forces when self-centering systems are used. 展开更多
关键词 Comparative analysis Buckling-restrained braces BRB Resilient slip-friction joint RSFJ
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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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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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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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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 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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Natural Heritage Value of Xinjiang Tianshan and Global Comparative Analysis 被引量:6
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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 analysis of rapamycin biosynthesis clusters between Actinoplanes sp. N902-109 and Streptomyces hygroscopicus ATCC29253 被引量:5
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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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Theoretical analysis of fluid mixing time in liquid-continuous impinging streams reactor 被引量:3
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作者 罗燕 周剑秋 +2 位作者 郭钊 余蓓 熊卉 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3217-3222,共6页
The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of ma... The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of macromixing time and micromixing time are quantitatively discussed. The results show that under a continuous and stable operating condition, as the paddle speed increases, the macromixing time and micromixing time calculated by the two models both decrease, even in a linkage equilibrium state. Simultaneously, as the paddle speed increases, the results figured by the two models tend to be consistent. It indicates that two models both are more suitable for calculation of mixing time in high paddle speed. Compared with the existing experimental results of this type of reactor, the mixing time computed in the speed of 1500 r/min is closer to it. These conclusions can provide an important reference for systematically studying the strengthening mechanism of LISR under continuous mixing conditions. 展开更多
关键词 impinging stream reactor empirical model theoretical model mixing time comparative analysis
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Computational interaction analysis of organophosphorus pesticides with different metabolic proteins in humans 被引量:3
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作者 Amit Kumar Sharma Karuna Gaur +1 位作者 Rajeev Kumar Tiwari Mulayam Singh Gaur 《The Journal of Biomedical Research》 CAS 2011年第5期335-347,共13页
Pesticides have the potential to leave harmful effects on humans, animals, other living organisms, and the environment. Several human metabolic proteins inhibited after exposure to organophosphorus pesticides absorbed... Pesticides have the potential to leave harmful effects on humans, animals, other living organisms, and the environment. Several human metabolic proteins inhibited after exposure to organophosphorus pesticides absorbed through the skin, inhalation, eyes and oral mucosa, are most important targets for this interaction study. The crystal structure of five different proteins, PDBIDs: 3LII, 3NXU, 4GTU, 2XJ1 and 1YXA in Homo sapiens (H. sapiens), interact with organophosphorus pesticides at the molecular level. The 3-D structures were found to be of good quality and validated through PROCHECK, ERRAT and ProSA servers. The results show that the binding energy is maximum -45.21 relative units of cytochrome P450 protein with phosmet pesticide. In terms of H-bonding, methyl parathion and parathion with acetylcholinesterase protein, parathion, methylparathion and phosmet with protein kinase C show the highest interaction. We conclude that these organophosphorus pesticides are more toxic and inhibit enzymatic activity by interrupting the metabolic pathways in H. sapiens. 展开更多
关键词 DOCKING organophosphorus pesticides comparative analysis MODELING toxicity analysis acetylcholinesterases Homo sapiens
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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 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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Structural characterization and comparative analysis of the chloroplast genome of Ginkgo biloba and other gymnosperms 被引量:3
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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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