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Identification and characterization of FpRco1 in regulating vegetative growth and pathogenicity based on T-DNA insertion in Fusarium pseudograminearum
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作者 Haiyang Li Yuan Zhang +18 位作者 Cancan Qin Zhifang Wang Lingjun Hao Panpan Zhang Yongqiang Yuan Chaopu Ding Mengxuan Wang Feifei Zan Jiaxing Meng Xunyu Zhuang Zheran Liu Limin Wang Haifeng Zhou Linlin Chen Min Wang Xiaoping Xing Hongxia Yuan Honglian Li Shengli Ding 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3055-3065,共11页
Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.... Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.pseudograminearum infects wheat remains unclear.In this study,we aimed to elucidate these mechanisms by constructing a T-DNA insertion mutant library for the highly virulent strain WZ-8A of F.pseudograminearum.By screening this mutant library,we identified nine independent mutants that displayed impaired pathogenesis in barley leaves.Among these mutants,one possessed a disruption in the gene FpRCO1 that is an ortholog of Saccharomyces cerevisiae RCO1,encoding essential component of the Rpd3S histone deacetylase complex in F.pseudograminearum.To further investigate the role of FpRCO1 in F.pseudograminearum,we employed a split-marker approach to knock out FpRCO1 in F.pseudograminearum WZ-8A.FpRCO1 deletion mutants exhibit reduced vegetative growth,conidium production,and virulence in wheat coleoptiles and barley leaves,whereas the complementary strain restores these phenotypes.Moreover,under stress conditions,the FpRCO1 deletion mutants exhibited increased sensitivity to NaCl,sorbitol,and SDS,but possessed reduced sensitivity to H_(2)O_(2)compared to these characteristics in the wild-type strain.RNA-seq analysis revealed that deletion of FpRCO1 affected gene expression(particularly the downregulation of TRI gene expression),thus resulting in significantly reduced deoxynivalenol(DON)production.In summary,our findings highlight the pivotal role of FpRCO1 in regulating vegetative growth and development,asexual reproduction,DON production,and pathogenicity of F.pseudograminearum.This study provides valuable insights into the molecular mechanisms underlying F.pseudograminearum infection in wheat and may pave the way for the development of novel strategies to combat this devastating disease. 展开更多
关键词 Fusarium pseudograminearum t-dna insertion Rpd3S complex FpRCO1 PATHOGENICITY DON production
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Genetic Analysis of a Small Grain Mutant Induced by T-DNA Insertion in Rice 被引量:5
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作者 张向前 朱海涛 +1 位作者 邹金松 曾瑞珍 《Agricultural Science & Technology》 CAS 2008年第3期63-66,91,共5页
[Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-... [Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-DNA tag lines, the progeny of homozygous plants carrying T-DNA insertion were screened for mutants with mutated phenotypes. The genetic analysis of the mutant and test for the linkage between the mutated phenotype and the T-DNA insertion were carried out to determine its genetic characteristics. [Result] In the present study, a grain shape mutant induced by T-DNA insertion in rice was identified, which showed small grain. Genetic analysis of the mutant showed that the two types of phenotype, normal and small grain in the segregating populations derived from the T-DNA heterozygotes, fit the ratio of 3∶1. Test for Basta resistance showed that all the mutants were resistant while the normal plants segregated for resistant and susceptible by the ratio of 2∶1. The results indicated that the mutant phenotype cosegregated with Bar gene. The small grain mutant caused by T-DNA insertion was confirmed by PCR amplification aiming at T-DNA. [Conclusion] The grain shape mutant is useful for isolation of the tagged gene and genetic improvement in rice. 展开更多
关键词 ORYZA SATIVA GRAIN shape MUTANT t-dna insertion
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Studies on rice seed quality through analysis of a large- scale T-DNA insertion population 被引量:10
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作者 Fang-Fang Fu Rui Ye Shu-Ping Xu Hong-Wei Xue 《Cell Research》 SCIE CAS CSCD 2009年第3期380-391,共12页
A rice (Oryza sativa) T-DNA insertion population, which included more than 63 000 independent transgenic lines and 8 840 identified flanking sequence tags (FSTs) that were mapped onto the rice genome, was develope... A rice (Oryza sativa) T-DNA insertion population, which included more than 63 000 independent transgenic lines and 8 840 identified flanking sequence tags (FSTs) that were mapped onto the rice genome, was developed to systemi- cally study the rice seed quality control. Genome-wide analysis of the FST distribution showed that T-DNA insertions were positively correlated with expressed genes, but negatively with transposable elements and small RNAs. In addition, the recovered T-DNAs were preferentially located at the untranslated region of the expressed genes. More than 11 000 putative homozygous lines were obtained through multi-generations of planting and resistance screening, and measurement of seed quality of around half of them, including the contents of starch, amylose, protein and fat, with a nondestructive near-infrared spectroscopy method, identified 551 mutants with unique or multiple altered param- eters of seed quality. Analysis of the corresponding FSTs showed that genes participating in diverse functions, including metabolic processes and transcriptional regulation, were involved, indicating that seed quality is regulated by a complex network. 展开更多
关键词 RICE t-dna insertion population seed quality near-infrared spectroscopy
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A Novel Insertion Solution for the Travelling Salesman Problem
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作者 Emmanuel Oluwatobi Asani Aderemi Elisha Okeyinka +5 位作者 Sunday Adeola Ajagbe Ayodele Ariyo Adebiyi Roseline Oluwaseun Ogundokun Temitope Samson Adekunle Pragasen Mudali Matthew Olusegun Adigun 《Computers, Materials & Continua》 SCIE EI 2024年第4期1581-1597,共17页
The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) a... The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine.The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and NNH.This guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match tothe optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing currentinsertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also createsnew possibilities for progress in heuristic design and optimization methodologies. 展开更多
关键词 Nearest neighbour heuristic farthest insertion heuristic half max insertion heuristic tour construction travelling salesman problem
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T-DNA transfer and integration as a tool for insertional mutagenesis in the taxol-producing fungus 被引量:1
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作者 迟彦 Ping Wenxiang +4 位作者 Li Shanshan Zhu Jing Ma Xi Gao Fengshan Zhou Dongpo 《High Technology Letters》 EI CAS 2008年第1期92-97,共6页
Agrobacterium tumefaciens-mediated DNA transiormation method was applied to transform Noclulisporium sylviforme fusant HDF-68, a taxol-produeing fungus. We constructed a binary vector pBI121-43 canting a hygromycin-re... Agrobacterium tumefaciens-mediated DNA transiormation method was applied to transform Noclulisporium sylviforme fusant HDF-68, a taxol-produeing fungus. We constructed a binary vector pBI121-43 canting a hygromycin-resistant gene cassette between the right and left borders of T-DNA, Optimal co-cultivation of N.sylviforrne with A. tumefaciens containing pBI121-43 led to 110- 130 hygromycin-resistant transformants per" million eonidia. Putative transformants were found to be mitotically stable. The molecular analysis of transformants demonstrated the random integration of single copy of the T-DNA into the host genome. This transformation system serves as a basic tool for insertional mutagenesis in N. sylviforme fusant HDF-68, and the development of such svstem lays a solid foundation for constructing high-yied gene engineering strain and clarifying taxol biosynthesis pathway in this fungus. 展开更多
关键词 TAXOL t-dna insertional mutagenesis
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Production of Light Fraction-Based Pyrolytic Fuel from Spirulina platensis Microalgae Using Various Low-Cost Natural Catalysts and Insertion
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作者 Indra Mamad Gandidi Sukarni Sukarni +4 位作者 Avita Ayu Permanasari Purnami Purnami TuanAmran Tuan Abdullah Anwar Johari Nugroho Agung Pambudi 《Energy Engineering》 EI 2024年第12期3635-3648,共14页
The use of catalysts has significantly enhanced the yield and quality of in-situ pyrolysis products.However,there is a lack of understanding regarding pyrolysis approaches that utilize several low-cost natural catalys... The use of catalysts has significantly enhanced the yield and quality of in-situ pyrolysis products.However,there is a lack of understanding regarding pyrolysis approaches that utilize several low-cost natural catalysts(LCC)and their placement within the reactor.Therefore,this study aims to examine the effects of various LCC on the insitu pyrolysis of spirulina platensis microalgae(SPM)and investigate the impact of different types of catalysts.We employed LCCsuch as zeolite,dolomite,kaolin,and activated carbon,with both layered and uniformlymixed LCCSPM placements.Each experiment was conducted at a constant temperature of 500℃for 60 min.The resulting pyrolytic liquids(bio-oil)and syngas were analyzed using a Gas Chromatography Mass Spectrometry(GC-MS)analyzer to determine the distribution of hydrocarbon compounds.The experimental results indicated that the presence of catalysts significantly influenced the mass yield productivity of liquid fuels and syngas.Activated carbon and zeolite were preferred among the four catalysts for producing liquid fuels(22.4 and 18.6 wt%)when layered and uniformly mixed,respectively.Kaolin with a layered mixture with SPM was more suitable for the production of light fractions(C_(5)–C_(12)),achieving approximately 95.7%peak area,while zeolite with a uniform mixture produced the highest light fraction at about 86.3%peak area.All catalysts except kaolin significantly increased the aromatic compounds in the liquid fuels.Although the amount of oxygenated hydrocarbons in the bio-oil remained relatively high,the final hydrocarbon composition was highly comparable to conventional fuels such as gasoline-88,which has a C_(5)–C_(12)hydrocarbon distribution of approximately 88.1%peak area.Regarding the syngas products,all catalysts except activated carbon successfully converted nitromethane compounds into tetranitromethane hydrocarbons,with activated carbon predominantly yielding nitromethane compounds. 展开更多
关键词 Pyrolysis in-situ SPM LCC BIO-OIL SYNGAS insertion
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Enhancing hydrogen evolution and oxidation kinetics through oxygen insertion into nickel lattice
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作者 Wanli Liang Xiyu Gong +9 位作者 Jinchang Xu Zixuan Dan Fanyan Xie Hulei Yu Hao-Fan Wang Yanshuo Jin Hongjuan Wang Yonghai Cao Hui Meng Hao Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期529-539,I0012,共12页
Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution rea... Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution reaction(HER)and hydrogen oxidation reaction(HOR).In this paper,an oxygen insertion strategy was applied on nickel to regulate its hydrogen electrocatalytic performance,and the oxygen-inserted nickel catalyst was successfully obtained with the assistance of tungsten dioxide support(denoted as O-Ni/WO_(2)).The partial insertion of oxygen in Ni maintains the face-centered cubic arrangement of Ni atoms,simultaneously expanding the lattice and increasing the lattice spacing.Consequently,the adsorption strength of^(*)H and^(*)OH on Ni is optimized,thus resulting in superior electrocatalytic performance of0-Ni/WO_(2)in alkaline HER/HOR.The Tafel slope of O-Ni/WO_(2)@NF for HER is 56 mV dec^(-1),and the kinetic current density of O-Ni/WO_(2)for HOR reaches 4.85 mA cm^(-2),which is ahead of most currently reported catalysts.Our proposed strategy of inserting an appropriate amount of anions into the metal lattice could provide more possibilities for the design of high-performance catalysts. 展开更多
关键词 Hydrogen evolution Hydrogen oxidation NICKEL Oxygen insertion Adsorption free energy
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An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica
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作者 Zhongyi ZHANG Hang LIU +5 位作者 Xiaohui PAN Yanan ZONG Leili FENG Lixian LIU Li GUO Guanpin YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期216-225,共10页
Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-st... Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species. 展开更多
关键词 Nannochloropsis oceanica genetic transformation random insertional mutant library zeocin pretreatment forward genetics
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Velamentous Cord Insertion: Interest of Antenatal Diagnosis and Review of the Literature
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作者 Karam Harou Aboubacar Sidiki Sidibe +1 位作者 Hicham Abdelkhalki Abderaouf Soummani 《Open Journal of Obstetrics and Gynecology》 2024年第2期234-239,共6页
Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be d... Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be diagnosed during the morphological ultrasound of the 2nd trimester, actively looking for the association with a vasa previa, due to the risk of fetal haemorrhagic threat. We report an antenatal diagnosis of velamentous cord insertion and its management with literature review. 展开更多
关键词 Velamentous Cord insertion Vasa Previa Antenatal Diagnosis Ultrasound Doppler Benckiser’s Hemorrhage
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Treatment of benign rectal stricture caused by repeated anal insertion by endoscopy and balloon dilation:A case report
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作者 Shih-Hung Liu Jung-Cheng Kang +3 位作者 Je-Ming Hu Chao-Yang Chen Kuan-Hsun Lin Ta-Wei Pu 《World Journal of Gastrointestinal Endoscopy》 2024年第2期91-97,共7页
BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have dive... BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have diverse etiologies,including various inflammatory conditions.Benign strictures are usually managed by surgery and endoscopy.We present an unusual etiology of benign rectal stricture caused by the repeated insertion of foreign objects into the rectum for sexual purposes,resulting in rectal injury and subsequent chronic inflammation.CASE SUMMARY A 53-year-old man presented to the outpatient clinic of the Colorectal Surgery Department with symptoms of chronic constipation and bloody stools.The patient previously experienced rectal injury due to foreign object insertion for sexual purposes.Colonoscopy revealed benign circumferential narrowing of the rectum.He underwent treatment by endoscopic argon plasma coagulation and balloon dilation and follow-up as an outpatient for 4 months.A colonoscopy at the end of the follow-up period revealed no evidence of rectal stricture relapse.CONCLUSION A history of rectal injury,followed by chronic inflammation,should be considered in patients with benign rectal strictures.Management with endoscopic argon plasma coagulation and balloon dilation can prevent the need for surgical resection of benign rectal strictures. 展开更多
关键词 Chronic rectal inflammation COLONOSCOPY Benign rectal stricture Foreign body insertion Rectal injury Case report
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Regulation of AtbZIP1 Gene Expression by T-DNA Insertion in Arabidopsis thaliana
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作者 SUN Xiaoli SHAO Wanchen CAI Hua ZHU Yanming 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期19-23,共5页
bZIP transcription factor family is one of the largest groups of the plant transcription factor families and plays an important role in plant growth and adaption to the abiotic stresses. In this study, two AtbZIP1 mut... bZIP transcription factor family is one of the largest groups of the plant transcription factor families and plays an important role in plant growth and adaption to the abiotic stresses. In this study, two AtbZIP1 mutant Arabidopsis (bzipl) were used with T-DNA inserted into two different sites, designated as SALK-556773 and SALK-660942, in order to identify different effects on AtbZIP1 gene expression by different T-DNA insertion sites. PCR and RT-PCR results revealed that T-DNA insertion in CDS region could effectively inhibit AtbZIP1 gene expression, while T-DNA insertion in 3'-UTR couldn't. The phenotype analysis further confirmed the differences and showed that T-DNA insertion in CDS region decreased plants' drought resistance, while in 3'-UTR couldn't. The phenotype assays also suggested that AtbZIP1 held pivotal roles in plant response to drought stress. 展开更多
关键词 t-dna insertion AtbZIP1 different sites drought stress Arabidopsis thaliana
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Isolation of T-DNA flanking plant DNA from T-DNAinsertional embryo-lethal mutants of Arabidopsis thaliana by plasmid rescue technique
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作者 YAO XIAO LI JIAN GE SUN, ZHI PING ZHU (Chinese National Laboratory of Plant Molecular Genetics,Shanghai Institute of Plant Physiology, Chinese Academy of Sinica, Shanghai 200032, China) (Present address: 1100 Longwu Road, Shanghai Botanical Garden, Shang 《Cell Research》 SCIE CAS CSCD 1996年第2期125-136,共12页
Three T-DNA insertional embryonic lethal mutants from NASC (The Nottingham Arabidopsis Stock Center)were first checked with their segregation ratio of abortive and normal seeds and the copy number of T-DNA insertion. ... Three T-DNA insertional embryonic lethal mutants from NASC (The Nottingham Arabidopsis Stock Center)were first checked with their segregation ratio of abortive and normal seeds and the copy number of T-DNA insertion. The N4081 mutant has a segregation ratio of 1:3.04in average and one T-DNA insertion site according to our assay It was therefore chosen for further analysis. To isolate the joint fragment of T-DNA and plan DNA, the plasmid rescue technique waJs used. pEL-7, one of plasmids from left border of T-DNA, which contained pBR322 was selected from ampicillin plate. The T-DNA fragment of pEL-7 was checked by restriction enzyme analysis and Southern Blot. Restriction analysis confirmed the presence of known sites of EcoRI, PstI and PvuII on it.For confirming the presence of flanking plant DNA in this plasmid, pEL-7 DNA was labeled and hybridized with wild type and mutant plant DNA. The Southern Blot indicated the hybridization band in both of them. Furthermore, the junction of T-DNA/plant DNA was subcloned into bluescript SK+ and sequenced by Applied Biosystem 373A Sequencer. The results showed the 822 bp fragment contained a 274 bp sequence, which is 99.6%homolog (273bp/274 bp) to Ti plasmid pTi 15955 DNA.Ten bp of left 25 bp border repeat were also found in the juction of T-DNA and Plant DNA.Taken together, pEL-7 should contain a joint fragment of T-DNA and flanking plant DNA. This plasmid DNA could be used for the isolation of plant gene, which will be helpful to elucidate the relationship between gene function and plant embryo development. 展开更多
关键词 Arabidopsis thaliana embryo-lethal mutant plasmid rescue t-dna insertion flanking plant DNA
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Construction of Mutant Populations by T-DNA Insertion for Functional Genomic Study in Cotton
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作者 Jia-he WU, Kai-jing ZUO, Yi-chun NIE, Xian-long ZHANG(National Key Laboratory for Genetic Improvements of Crops, Huazhong Agricultural University, Wuhan 430070, China) 《棉花学报》 CSCD 北大核心 2002年第S1期48-48,共1页
The use of transfer DNA(T-DNA)as amutagen has been developed for tagging genes inmany crops,and results showed that T-DNAinsertion is a random event,and that theinserted genes are stable through multiplegenerations.Th... The use of transfer DNA(T-DNA)as amutagen has been developed for tagging genes inmany crops,and results showed that T-DNAinsertion is a random event,and that theinserted genes are stable through multiplegenerations.Through sequencing PCR-amplifiedfragments adjacent to the inserted elements,wecan construct the T-DNA flanking database,which would be useful for cloning the genestagged by T-DNA. 展开更多
关键词 COTTON DNA MUTANT CLONING GENOMIC sequencing inserted CROPS COTTON MUTANT
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Path-Based Timing Optimization by Buffer Insertion with Accurate Delay Model
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作者 张轶谦 周强 +1 位作者 洪先龙 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期520-525,共6页
An algorithm of path based timing optimization by buffer insertion is presented.The algorithm adopts a high order model to estimate interconnect delay and a nonlinear delay model based on look up table for gate dela... An algorithm of path based timing optimization by buffer insertion is presented.The algorithm adopts a high order model to estimate interconnect delay and a nonlinear delay model based on look up table for gate delay estimation.And heuristic method of buffer insertion is presented to reduce delay.The algorithm is tested by industral circuit case.Experimental results show that the algorithm can optimize the timing of circuit efficiently and the timing constraint is satisfied. 展开更多
关键词 buffer insertion timing optimization interconnect planning routing algorithm
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Parallel EOI algorithm with different insertion schemes
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作者 刘庆富 仲伟俊 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期283-288,共6页
A parallel embedding overlapped iterative (EOI) algorithm about classicimplicit equations with asymmetric Saul'yev schemes (CIS-EOI) to solve one-dimensional diffusionequations is discussed to improve the properti... A parallel embedding overlapped iterative (EOI) algorithm about classicimplicit equations with asymmetric Saul'yev schemes (CIS-EOI) to solve one-dimensional diffusionequations is discussed to improve the properties of the segment classic implicit iterative (SCII)algorithm. The structure of CIS-EOI method is given and the stability of scheme and convergence ofiteration are proved by matrix method. The property of gradual-approach convergence is alsodiscussed. It has been shown that the convergent rate is faster and the property of gradual-approachconvergence also becomes better with the increasing of the net point in subsystems than with theSCII algorithm. The simulation examples show that the parallel iterative algorithm with a differentinsertion scheme CIS-EOI is more effective. 展开更多
关键词 diffusion equation different insertion scheme convergent rate property ofgradual-approach convergence
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Fine-Grain Sleep Transistor Insertion for Leakage Reduction
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作者 杨华中 汪玉林 +1 位作者 海罗嵘 汪蕙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期258-265,共8页
A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mix... A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mixed-integer linear programming (MLP) problem in order to simultaneously place and size the sleep transistors optimally. Because of better circuit slack utilization, our experimental results show that the MLP model can save leakage by 79.75%, 93.56%, and 94.99% when the circuit slowdown is 0%, 3%, and 5%, respectively. The MLP model also achieves on average 74.79% less area penalty compared to the conventional fixed slowdown method when the circuit slowdown is 7%. 展开更多
关键词 leakage current reduction fine-grain sleep transistor insertion delay model mixed-integer linearprogramming
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Needle Steering for Robot-Assisted Insertion into Soft Tissue:A Survey 被引量:7
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作者 GAO Dedong LEI Yong ZHENG Haojun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期629-638,共10页
Needle insertion is a common surgical procedure used in diagnosis and treatment.The needle steering technologies make continuous developments in theoretical and practical aspects along with the in-depth research on ne... Needle insertion is a common surgical procedure used in diagnosis and treatment.The needle steering technologies make continuous developments in theoretical and practical aspects along with the in-depth research on needle insertion.It is necessary to summarize and analyze the existing results to promote the future development of theories and applications of needle insertion.Thus,a survey of the state of the art of research is presented on algorithms of needle steering techniques,the surgical robots and devices.Based on the analysis of the needle insertion procedure,the concept of needle steering is defined as a kinematics problem,which is to place the needle at the target and avoid the obstacles.The needle steering techniques,including the artificial potential field method and the nonholonomic model,are introduced to control the needles for improving the accuracy.Based on the quasi-static thinking,the virtual spring model and the cantilever-beam model are developed to calculate the amount of needle deflection and generate the needle path.The phantoms instead of the real tissue are used to verify the models mentioned in most of the experimentations.For the desired needle trajectories,the image-guided robotic devices and some novel needles are presented to achieve the needle steering.Finally,the challenges are provided involving the controllability of the long flexible needle and the properties of soft tissue.The results and investigations can be used for further study on the precision and accuracy of needle insertion. 展开更多
关键词 needle insertion needle steering robot-assisted needle insertion path planning needle deflection tissue deformation
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Position and complications of pedicle screw insertion with or without image-navigation techniques in the thoracolumbar spine:a meta-analysis of comparative studies 被引量:16
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作者 Jinshan Tang Ziqiang Zhu +2 位作者 Tao Sui Dechao Kong Xiaojian Cao 《The Journal of Biomedical Research》 CAS 2014年第3期228-239,共12页
Computer-navigated pedicle screw insertion is applied to the thoracic and lumbar spine to attain high insertion accuracy and a low rate of screw-related complications.However,some in vivo and in vitro studies have sho... Computer-navigated pedicle screw insertion is applied to the thoracic and lumbar spine to attain high insertion accuracy and a low rate of screw-related complications.However,some in vivo and in vitro studies have shown that no advantages are gained with the use of navigation techniques compared to conventional techniques.Additionally,inconsistent conclusions have been drawn in various studies due to different population characteristics and methods used to assess the accuracy of screw placement.Moreover,it is not clear whether pedicle screw insertion with navigation techniques decreases the incidence of screw-related complications.Therefore,this study was sought to perform a meta-analysis of all available prospective evidence regarding pedicle screw insertion with or without navigation techniques in human thoracic and lumbar spine.We considered in vivo comparative studies that assessed the results of pedicle screw placement with or without navigation techniques.PubMed,Ovid MEDLINE and EMBASE databases were searched.Three published randomized controlled trials(RCTs) and nine retrospective comparative studies met the inclusion criteria.These studies included a total of 732 patients in whom 4,953 screws were inserted.In conclusion,accuracy of the position of grade I,II,III and IV screws and complication rate related to pedicle screw placement were significantly increased when navigation techniques were used in comparison to conventional techniques.Future research in this area should include RCTs with well-planned methodology to limit bias and report on validated,patient-based outcome measures. 展开更多
关键词 META-ANALYSIS POSITION pedicle screw insertion navigation COMPLICATION
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Does flexible small-diameter colonoscope reduce insertion pain during colonoscopy? 被引量:7
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作者 Yoshiharu Uno Akihiro Munakata 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期659-663,共5页
AIM It is well known that colonoscopy can bedifficult due to abdominal pain induced duringcolonoscope insertion,if sedative agents are notgiven.Recently,an extra-flexible,small-diameter colonoscope(CF-SV,Olympus Inc.,... AIM It is well known that colonoscopy can bedifficult due to abdominal pain induced duringcolonoscope insertion,if sedative agents are notgiven.Recently,an extra-flexible,small-diameter colonoscope(CF-SV,Olympus Inc.,Japan)was developed in order to improve safetyand comfort.The aim of this study was toaccess the usefulness of the CF-SV.METHODS One hundred patients undergoingsigmoidoscopy were recruited and colonoscopywas performed by one experiencedcolonoscopist.First,a routine-type colonoscope(CF-2301)was inserted into the colon withoutsedation.When the patient complained ofabdominal pain(even if mild),the scope wasnot advanced further and was withdrawn afterthe anatomic location of its tip was determinedfluoroscopically.Then,the CF-SV was inserteduntil it reached the cecun or the site whereabdominal pain occurred.Previous abdominalsurgery and abdominal disease were consideredas unfavorable factors(UF)and the relationshipbetween abdominal pain and UF,age and genderwere investigated.Furthermore,the colonicinsertion pressures in 36 patients with abdominalpain were measured with a force gauge.RESULTS Thirty-four cases(34%)felt no painwith the CF-2301 and successful pancolon-0scopies to the cecum were performed.Sixty-six cases(66%)complained of abdominal pain.The procedure was painless for 47% of men and24% of women,respectively.The CF-2301 scopefailed to reach the sigmoid-descending colon junctions in 59(89.4%)of the 66 patientscomplaining of abdominal pain.However,CF-SVreached proximal area in 94.9% of those whofailed with CF-2301.The median pressure forpain-inducing was 700 g/cm^2.CONCLUSION Unsedated patients with UFwere prone to complain of pain when thestandard-type CF-2301 scope was used.Thenewly developed extra-flexible CF-SV is usefulfor the aged and for those with UF or being proneto suffer from abdominal pain.Sedative agentsmay be unnecessary if this new type ofcolonoscope is used. 展开更多
关键词 COLONOSCOPY ABDOMINAL PAIN FLEXIBLE colonoscope insertion pressure unfavorable factors SIGMOIDOSCOPY
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An Analysis of the Orthogonal Crank-rocking Lever Spatial Mechanism for the Weft Insertion in Rapier Looms 被引量:6
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作者 Li Kerang(李克让) +1 位作者 Chen Ming(陈明) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期27-31,共5页
On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are stu... On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are studied when the maximum swing angle of rocking lever and the length of outputting lever have different values, and the optimum parameters suitable for motion transmission can be chosen. At the same time some existing shortpoints of the mechanism are also pointed out. 展开更多
关键词 RAPIER loom WEFT insertion mechanism motion transmission performance.
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