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Polymorphism Analysis of the 3′ Flank Region of Equine IGF-Ⅰ Gene by PCR-SSCP 被引量:5
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作者 孟祥伟 额尔登其木格 +2 位作者 红海 李蓓 芒来 《Agricultural Science & Technology》 CAS 2008年第6期39-42,共4页
[Objective] To explore the polymorphism of the 3′ flank region of equine IGF-Ⅰ gene. [Method] The 3′ flank region sequences of IGF-Ⅰ gene were amplified from genomic DNA of 270 horses, which included 4 types of Mo... [Objective] To explore the polymorphism of the 3′ flank region of equine IGF-Ⅰ gene. [Method] The 3′ flank region sequences of IGF-Ⅰ gene were amplified from genomic DNA of 270 horses, which included 4 types of Mongolian horse, Sanhe horse and Thoroughbred, and then analyzed by PCR-SSCP. [Result] Three genotypes (AA, BB and AB) were detected by PCR-SSCP and the distribution of genotypes of all research objects except Xinihe horse and Baerhu horse were in line with the "Hardy-Weinberg Law". [Conclusion] There was a polymorphic locus in the 3′ flank region of IGF-Ⅰ gene, which might affect the equine growth and development mechanism. The study is of important theoretical and practical significance to improve the performance and to develop equine industry. 展开更多
关键词 IGF-Ⅰ 3′ flank REGION PCR-SSCP
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Isolation of the Flanking Sequences Adjacent to Transgenic T-DNA in Brassica napus Genome by an Improved Inverse PCR Method 被引量:2
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作者 杨坤 吴学龙 +1 位作者 朗春秀 陈锦清 《Agricultural Science & Technology》 CAS 2010年第2期65-68,139,共5页
[Objective] The research aimed to isolate flanking sequences adjacent to the transgenic T-DNA in Brassica napus by an improved inverse PCR method.[Method] Using single clone of transgenic FS4 in Brassica napus as the ... [Objective] The research aimed to isolate flanking sequences adjacent to the transgenic T-DNA in Brassica napus by an improved inverse PCR method.[Method] Using single clone of transgenic FS4 in Brassica napus as the research materials,total DNA was extracted from transgenic Brassica napus by using modified CTAB method.After enzyme digestion and purification,self-joining was made.Two circles of nested PCR and the sequence alignment were carried out.[Result] A fragement with the size of 4.0 kb was amplified ... 展开更多
关键词 Inverse PCR(IPCR) flanking sequences Improved CTAB method Transgenic Brassica napus
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Isolating the Mutator Transposable Element Insertional Mutant Gene mio16 of Maize Using Double SelectedAmplification of Insertion Flanking Fragments (DSAIFF)
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作者 ZHONG Wen-juan ZHANGMei-dong +4 位作者 YANG Liu-qi WANG Ming-chun ZHENG Yong-lian YANG Wen-peng GAO You-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第10期1592-1600,共9页
Mutator transposable element (Mu) has been used as an effective tool to clone maize (Zea mays L.) genes. One opaque endosperm mutant (miol6) was identified in a pool of Mu inserted mutants. A modified method, te... Mutator transposable element (Mu) has been used as an effective tool to clone maize (Zea mays L.) genes. One opaque endosperm mutant (miol6) was identified in a pool of Mu inserted mutants. A modified method, termed the double selected amplification of insertion flanking fragments (DSAIFF), was employed to isolate the Mu flanking fragments (MFFs) of miol6. The target site duplications (TSDs) isolated from the Msp I and Mse I digested MFFs had a same 9-bp sequence and were confirmed to be the flanking sequence of one identically inserted gene. Co-segregation analysis suggested that the MFFs were associated with the mutant opaque endosperm, and miol6 was mapped in silico onto the physical position ranged from 229 965 021 to 229 965 409 bp of the maize chromosome 4.09 bin. The full-length cDNA of the wild-type gene was obtained by an RT-PCR primer-scanning technique, and Mio16 was found to putatively encode a homolog of the Arabidopsis MAP3K delta-1 protein kinase. RT-PCR result the mRNA expression of miol6 region anchored by primers Mu20 and af276 was not interrupted by Mu insertion. Further researches will be done to elucidate how the expression of miol6 is alternated by Mu insertion. 展开更多
关键词 maize (Zea mays L.) Mutator (Mu) transposable element Mu flanking fragments (MFFs) double selected amplification of insertion flanking fragments (DSAIFF) miol6
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Ac/Ds Transposition Activity in Transgenic Rice Population and DNA Flanking Sequence of Ds Insertion Sites 被引量:6
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作者 朱正歌 付亚萍 +4 位作者 肖晗 胡国成 斯华敏 于永红 孙宗修 《Acta Botanica Sinica》 CSCD 2003年第1期102-107,共6页
The Agrobacterium mediated transgenic rice ( Oryza saliva L.) population with inserts of maize transposon Activator/Dissociation (Ac/Ds) was investigated. DNA sequences flanking the T-DNA were analyzed with inverse PC... The Agrobacterium mediated transgenic rice ( Oryza saliva L.) population with inserts of maize transposon Activator/Dissociation (Ac/Ds) was investigated. DNA sequences flanking the T-DNA were analyzed with inverse PCR. Results showed that 65.4% of the T-DNA was integrated in different locations of rice genome, and some T-DNA flanking sequences were located on certain chromosomes. A number of T-DNA was found to have inserted into protein coding regions. In order to induce transposition of the inserted Ds elements, 354 crosses of Ac x Ds and Ds x Ac were constructed. The excision frequency of Ds element trans-activated by Ac transposase was 22.7% in the F-2 populations, and the transposition was confirmed with analyses of DNA sequences flanking the Ds elements. In addition to the transposition due to 'cut-paste' mechanism, Ds can replicate itself and integrate into a new locus, and inaccurate excisions were also found. A proportion of DNA segments flanking the Ds elements showed no homologies to sequences published in GenBank, of which two were registered under the accession numbers AF355153 and AF355770. The strategy of using transposon tagging for rice genomics study was discussed. 展开更多
关键词 transposon Ac/Ds transposition activity flanking sequence Oryza sativa
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石榴子石Fe^(3+)含量电子探针原位分析:Flank Method方法的实例应用 被引量:8
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作者 李小犁 陶仁彪 +2 位作者 李清云 朱建江 张立飞 《岩石学报》 SCIE EI CAS CSCD 北大核心 2019年第4期1058-1070,共13页
电子探针分析技术主要应用于对物质进行快速无损的定性、定量分析,是材料科学和地质学领域最基础和重要的研究手段。而利用电子探针对矿物中不同价态Fe的含量进行原位定量分析,更是具有非常重要的科学意义。近来发展起来的可进行Fe^(3+)... 电子探针分析技术主要应用于对物质进行快速无损的定性、定量分析,是材料科学和地质学领域最基础和重要的研究手段。而利用电子探针对矿物中不同价态Fe的含量进行原位定量分析,更是具有非常重要的科学意义。近来发展起来的可进行Fe^(3+) 含量定量分析的电子探针Flank Method测试方法,相比早期的实验方法具有更高的准确度和精确性。该方法主要是通过定义Fe的特征X射线L能级谱线峰位的峰侧位置(flank position),对应了不同价态Fe吸收谱线的差值线谱(difference spectrum)中强度计数最大值(FeLα*)和最小值(FeLβ*)的位置,从而避免了在早期实验中,一般通过直接测量Fe的L能级峰位(FeLα和FeLβ)可能导致的测试不确定性。同时,该测试方法通过对电子探针谱仪系统进行实时的位移误差校正,确保其在某一个稳定的实验条件(周期)下具有可重现性(精确度)。在本文中,我们根据北京大学造山带与地壳演化教育部重点实验室的JEOL JXA-8100型号电子探针的实际性能状态,在前人建立的实验步骤基础上,进行了测试流程的自适性改进和修正,建立了更符合本实验室实际情况的电子探针Flank Method测试方法,用于分析石榴子石中的Fe^(3+) 含量。通过对已知Fe^(3+) 含量的标准石榴子石样品进行检测验证,确定了该方法的可行性、可靠性以及可重复性。在对天然样品的分析中,我们选择了来自我国天山、拉萨和北祁连的洋壳俯冲类型中低温(超)高压榴辉岩中的石榴子石样品,对其进行了Fe^(3+) 含量(环带)的分析。结果显示,石榴子石中Fe^(3+) 含量可作为一个可靠的氧逸度指示剂,其(环带)变化很好地对应了榴辉岩寄主岩石的变质演化轨迹,反映了在板片俯冲过程中,榴辉岩的氧逸度具有降低的趋势。 展开更多
关键词 电子探针 石榴子石 flank Method方法 三价铁
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Analysis of the Flanking Sequence and EventSpecific Detection of Transgenic Line W-4 of Brassica napus 被引量:1
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作者 陈松 申爱娟 +1 位作者 周晓婴 戚存扣 《Agricultural Science & Technology》 CAS 2014年第7期1089-1094,共6页
The genetically modified high-oleic rapeseed (Brassica napus L.) line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar We... The genetically modified high-oleic rapeseed (Brassica napus L.) line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar Westar.The transformation was mediated by Agrobacterium.The flanking sequences to both the left and right borders of T-DNA insertion site were amplified by thermal asymmetric interlaced PCR (TAIL-PCR) from the genomic DNA of the transgenic rapeseed line W-4.The flanking sequences to the right border was 290 bp in length and the nucleotide composition was 31.27% for G+C content while 68.73% for A+T content.The flanking sequence to the left border was 365 bp in length and the G+C content was 32.6% and the A+T content was 67.4%,indicating that the T-DNA was integrated in the A/T-rich region.Further more,sequence alignment analysis showed a deletion of 62 bp including the right border of pCNFIRnos and the integration of the whole left border except a change of G to A.That was to say,the integration of the T-DNA in the transgenic line W-4 not involved in the vector sequences.Based on both flanking sequences as well as the left and right borders of the T-DNA sequences,two pairs of specific primers TLF/TLR and TRF/TRR were designed.Using the primers the event-specific PCR detection method for transgenic rapeseed line W-4 was established.By the PCR,two fragments of 485 and 405 bp were amplified from the W-4 genomic DNA as expected,while no products were amplified from the genomic DNA of other transgenic rapeseed lines and non-transgenic rapeseed line.And by the PCR it is possible to detect the W-4 genomic DNA from a mixed sample of genomic DNA.The limit of the detection for the qualitative PCR assay was 0.1%.The method developed in this work is highly specific,sensitive and suitable for event-specific detection of the transgenic rapeseed line W-4. 展开更多
关键词 Transgenic rapeseed flanking sequences Event-specific detection
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Identification and isolation of Mu-flanking fragments from maize 被引量:4
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作者 Yijun Wang Guangming Yin +4 位作者 Qin Yang Jihua Tang Xiaomin Lu Schuyler S. Korban Mmghang Xu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第4期207-213,共7页
Transposable elements have been utilized as mutagens to create mutant libraries for functional genomics. Isolation of genomic segments flanking the insertion Mutator (Mu) is a key step in insertion mutagenesis studi... Transposable elements have been utilized as mutagens to create mutant libraries for functional genomics. Isolation of genomic segments flanking the insertion Mutator (Mu) is a key step in insertion mutagenesis studies. Herein, we adopted a modified AFLP method to identify and isolate Mu-flanking fragments from maize. The method consists of the following steps: 1) double-digestion of genomic DNA with Bgl II/Msp I and ligation of digested fragments to the Bgl II- and Msp I-adaptors; 2) enrichment of a subset of Bgl II/Msp I fragments followed by selective amplification of the Mu-flanking fragments; 3) simultaneous display of AFLP bands derived from the flanking regions for both insert and native Mu transposons; 4) identification and isolation of AFLP bands resulting from Mu insertions by comparing the banding profiles between Mu-induced mutants and their parental lines; and 5) confirmation of flanking fragments related to these Mu insertions. Using this approach, we have isolated flanking fragment(s) resulting from Mu insertion for every Mu-induced mutant, and one such fragment, M196-FF, is found to contain a partial sequence of the DNA topoisomerase I gene Topl. Moreover, the modified AFLP method including all restriction enzymes, adaptors and primers has been optimized in this study. The modified AFLP method has been proved to be simple and efficient in the isolation of Mu-flanking fragments and will find its usefulness in the functional genomics of maize. 展开更多
关键词 Mutator transposon flanking fragment AFLP MAIZE
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Trace and rare earth element geochemistry of the black and grey shales of the Calabar Flank, Southeastern Nigeria: constraints on the depositional environment and the degree of metal enrichment 被引量:1
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作者 Christopher Iorfa Adamu Benjamin Odey Omang +2 位作者 Oluwaseye Peter Oyetade Otu Johnson Therese Ntonzi Nganje 《Acta Geochimica》 EI CAS CSCD 2021年第3期312-324,共13页
This study focuses on the trace and rare earth elements(REE)geochemistry of the Nkporo and Ekenkpon Shales of the Calabar Flank.The main aim is to infer their depositional environment and the degree of their metal enr... This study focuses on the trace and rare earth elements(REE)geochemistry of the Nkporo and Ekenkpon Shales of the Calabar Flank.The main aim is to infer their depositional environment and the degree of their metal enrichment.The shale samples were analyzed using inductively coupled plasma mass spectrometry.The results indicated that the mean concentrations of K,Na,and Fe in Nkporo and Ekenkpon Shales are 1.45,0.4,and 4.17 wt%,and 1.11,0.44,and 5.42 wt%;respectively.The Nkporo Shale is enriched with the following trace elements;P>Mn>Sr>Ba>Zn>Ce>Rb>Zr>V>Cr>Ni and depleted in the following trace elements;Ta>Ge>Sb>Bi>Cd>Ag>Te>In>Hg.While the Ekenkpon Shale is enriched with the following trace elements;P>Mn>Ba>Sr>V>Ce>Zr>Rb>Cr>Zn>Ni and depleted in;Sb>Ge>Bi>Ag>Ce>Te>In>Hg.The concentration of redox-sensitive elements such as V,Ni,Mo,U,Cu,Cr,Re,Cd,Sb,Ti,Mn,and their ratio V/Mo and U/Mo in the black and grey shale samples show different patterns.The REE obtained from the Nkporo and Ekenkpon Shales were PAAS normalized.The Nkporo Shale showed a slightly flat light rare-earth element(LREE),middle rare-earth element(MREE),and heavy rare earth element(HREE)pattern enrichment.Ce/Ce*ranges from 0.95 to 1.09 in Nkporo Shale and 0.67 to 1.40 in Ekenkpon Shale.The Ekenkpon Shale showed a slight LREE,MREE enrichment,and depleted HREE patterns.The Mn contents and U/Mo ratio in Nkporo and Ekenkpon Shales suggests a poor oxygen transitional environment.The V/Mo and V/(V+Ni)ratios indicated that the Nkporo shales were deposited in an anoxic to suboxic conditions and Ekenkpon shales were also deposited under an anoxic to suboxic conditions.The V/Ni ratio indicated that the organic matter in the Nkporo shale is terrigenous while that of the Ekenkpon shales are both terrigenous and marine in origin. 展开更多
关键词 Rare-earth elements(REE) Trace elements Calabar flank SUBOXIC ANOXIC
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Genomic structure analysis of SNC6, a progesterone-receptor associated protein gene, and cloning and characterization of its 5'-flanking region 被引量:1
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作者 曹江 郑树 +2 位作者 叶景佳 耿礼义 方永明 《Journal of Zhejiang University Science》 CSCD 2002年第1期100-105,共6页
Objective: To analyze the genomic structure of SNC6, a progesterone\|receptor associated protein gene and its regulatory elements in its 5'\|flanking region. Methods: Genomic sequence from GenBank database (access... Objective: To analyze the genomic structure of SNC6, a progesterone\|receptor associated protein gene and its regulatory elements in its 5'\|flanking region. Methods: Genomic sequence from GenBank database (accession number: Z98048) covering the whole SNC6 gene was used to analyze the genomic structure of SNC6 and design primers for PCR amplification of its 5'\|flanking region. A 1894 bp fragment of the 5'\|flanking region \{(-1814\} to +75) was cloned by PCR using genomic DNA from a healthy donor peripheral blood lymphocyte as template. This fragment, as well as 3 shorter derivative fragments (1423 bp, 632 bp and 416 bp, which correspond to -1344 to +75, -552 to +75 and -337 to +75 respectively), were subcloned into pGL2 series luciferase reporter vectors. These constructs were introduced into colorectal cancer cell line SW620 for transient expression of reporter gene and luciferase activities were measured. Results: The genomic structure analysis showed there are 12 exons for SNC6 gene, which spans 32017 bp (nt71529 to nt39513 in Z98048 sequence). All transfected SW620 cells with the above 5\|flanking region\|containing constructs showed luciferase activities. The highest luciferase activities were measured in transfected cells with vectors containing 1894 bp fragments, and the lowest luciferase activities were measured in transfected cells with vectors containing 416 bp fragments. Luciferase activities were higher in transfected cells with vectors containing 632 bp fragments than that in transfected cells with vectors containing 1423 bp fragments. Conclusion: The basic transcription\|promoting element (promoter) for SNC6 expression resides between 0 to -337, and two transcription\|enhancing elements (enhancer) resides between -337 to -552 and -1344 to -1814, whereas one transcription\|inhibiting element (silencer) exists between -552 to -1344. 展开更多
关键词 SNC6 gene genomic structure 5'\|flanking region PROMOTER luciferase assay
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Generation of tool path for flank milling in divided areas
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作者 孙春华 刘华明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第4期31-33,共3页
Presents the division of non developable ruled surface into divided small areas and flank milling in these divided areas to improve machining efficiency and machined surface quality by controlling the machining error ... Presents the division of non developable ruled surface into divided small areas and flank milling in these divided areas to improve machining efficiency and machined surface quality by controlling the machining error for each area, and the algorithms developed for generation of tool path and calculation of errors, and concludes from computer simulation results that the algorithms are correct. 展开更多
关键词 flank MILLING in divided area GENERATION of tool path 5 AXIS NC MACHINING
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Flank gland-secreted putative chemosignals pertaining to photoperiod,endocrine states,and sociosexual behavior in golden hamsters
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作者 Ying-Juan LIU Da-Wei WANG +2 位作者 Lixing SUN Jin-Hua ZHANG Jian-Xu ZHANG 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第6期800-812,共13页
Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Us... Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Using gas chromatography-mass spectrometry, we detected compounds from the flank glands of males, only eight of which were also produced in females. Based on these chemical data we performed a number of further experiments. By manipulating light we found that males exposed to short-photoperiods developed smaller flank glands than those exposed to long-photoperiods. Six flank gland volatiles reduced in relative abundance, which possibly coded for reproductive status of males of this seasonally breeding hamster species. Through dyadic encounters, we were able to induce the formation of dominant-subordinate relationships and show that two glandular compounds became high in relative abundance and may function as dominance pheromones. Castration eliminated all male-specific compounds resulting from flank glands, but bilateral ovariectomies only affected one compound in females. Once these ovariectomized females were treated with testosterone, their glandular compounds resembled those of males, suggesting these compounds are under the main control of androgen. Two female putative pheromones, tetradeeanoic acid and hexadecanoic acid, were used in binary choice tests and were both found to attract males over females. Applying a solution of these pheromone compounds to adult males also suppressed their agonistic behavior [Current Zoology 56 (6): 800-812, 2010]. 展开更多
关键词 Dominance flank gland GONADECTOMY PHOTOPERIOD Putative pheromone Testosterone
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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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Reliability of the Brownish-flanked Bush Warbler's soft song in male-male conflict
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作者 Canwei Xia Boye Liu +2 位作者 Daiping Wang Huw Lloyd Yanyun Zhang 《Chinese Birds》 CSCD 2015年第2期107-112,共6页
Background: Soft song is a low-amplitude song produced by many birds. Recent studies have confirmed that soft song is an aggressive signal. For example, the Brownish-flanked Bush Warblers Cettia fortipes use soft song... Background: Soft song is a low-amplitude song produced by many birds. Recent studies have confirmed that soft song is an aggressive signal. For example, the Brownish-flanked Bush Warblers Cettia fortipes use soft song in male-male conflicts, particularly prior to attacks. Although stable signaling systems require that signals be honest on average,models predict that cheating is an acceptable strategy for some individuals or in some contexts.Methods: This study aimed to test the reliability of soft song as an aggressive signal in the brownish-flanked bush warbler. We used mounted specimens accompanied by broadcast songs or soft songs to simulate a male attempting to invade an existing territory.Results: We found the mounted specimen that coupled playback of soft songs suffered more and quicker attacks from the territory owner and that the relationship between soft song and subsequent attack in the territory owner was far from perfect. We observed territory owners that both over-signaled(i.e., produced soft song but did not attack) and under-signaled(i.e., attacked without producing soft song). Under-signaling territory owners were relatively more commonly than were over-signaling territory owners, particularly in simulated intrusion that coupled playback of soft song with a mount specimen.Conclusions: We discuss the cost of producing soft song and the potential benefit of the unreliable use of soft song and propose a new hypothesis for under-signaling with soft song; i.e., under-signaling territory owners might benefit from taking the initiative in fights. 展开更多
关键词 Aggressive signal Brownish-flanked BUSH WARBLER Cost Reliability Soft SONG
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Pattern Recognition for Flank Eruption Forecasting: An Application at Mount Etna Volcano (Sicily, Italy)
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作者 A. Brancato P. M. Buscema +1 位作者 G. Massini S. Gresta 《Open Journal of Geology》 2016年第7期583-597,共16页
A volcano can be defined as a complex system, not least for the hidden clues related to its internal nature. Innovative models grounded in the Artificial Sciences, have been proposed for a novel pattern recognition an... A volcano can be defined as a complex system, not least for the hidden clues related to its internal nature. Innovative models grounded in the Artificial Sciences, have been proposed for a novel pattern recognition analysis at Mt. Etna volcano. The reference monitoring dataset dealt with real data of 28 parameters collected between January 2001 and April 2005, during which the volcano underwent the July-August 2001, October 2002-January 2003 and September 2004-April 2005 flank eruptions. There were 301 eruptive days out of an overall number of 1581 investigated days. The analysis involved successive steps. First, the TWIST algorithm was used to select the most predictive attributes associated with the flank eruption target. During his work, the algorithm TWIST selected 11 characteristics of the input vector: among them SO<sub>2</sub> and CO<sub>2</sub> emissions, and also many other attributes whose linear correlation with the target was very low. A 5 × 2 Cross Validation protocol estimated the sensitivity and specificity of pattern recognition algorithms. Finally, different classification algorithms have been compared to understand if this pattern recognition task may have suitable results and which algorithm performs best. Best results (higher than 97% accuracy) have been obtained after performing advanced Artificial Neural Networks, with a sensitivity and specificity estimates over 97% and 98%, respectively. The present analysis highlights that a suitable monitoring dataset inferred hidden information about volcanic phenomena, whose highly non-linear processes are enhanced. 展开更多
关键词 Mt. Etna Volcano flank Eruption Forecasting Neural Networks Pattern Recognition Monitoring Data
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A New Northern Flank: Sweden and Finland in NATO
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作者 Magnus Christiansson 《International Relations and Diplomacy》 2023年第5期225-232,共8页
On June 282022 Sweden and Finland were invited to join NATO.During a symbolic ceremony at the NATO Madrid Summit,all the central actors gathered in front of the cameras,as if to replicate a“family photo”in mini form... On June 282022 Sweden and Finland were invited to join NATO.During a symbolic ceremony at the NATO Madrid Summit,all the central actors gathered in front of the cameras,as if to replicate a“family photo”in mini format:representatives from Sweden,Finland,and Turkey,as well as Secretary General Stoltenberg.The atmosphere was mixed:tense because of the dramatic backdrop of the Summit,relief because of the speedy process that had taken the process further.It was finally happening:Sweden and Finland would join the Atlantic Pact.But how did they get there?Over a few hectic months,two countries strongly associated with neutrality had moved their policies from emphasizing continuity to altering the very foundations of their security.Not only NATO critics were taken by surprise.Many NATO supporters were astonished by the rapid pace and the turnaround of the Swedish Social Democratic party.The relatively quick turnaround in Stockholm also meant that questions about the future and the consequences of NATO membership were postponed,not least because the Swedish election campaign put a lid on debate about strategic consequences:what journey awaits in the future and what strategic consequences does a future NATO membership have?This article discusses these questions in the belief that the temporal perspectives are connected:Sweden’s historical collaboration with NATO had significance for the country’s partner relationship,and in turn this influenced how Sweden became a member and what challenges the country faces together with its allies on a new northern flank in Europe. 展开更多
关键词 Sweden NATO Cold War ENLARGEMENT Northern flank
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FLANK DRIVE’Plus开口扳手
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作者 张淑珍 《汽车维修与保养》 2002年第9期16-16,共1页
关键词 flank DRIVE'Plus开口扳手 设计 性能 Snap-on公司
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Wettable-Flanks QFN汽车电子器件封装技术
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作者 奚啸晨 《中国集成电路》 2023年第6期81-85,共5页
Wettable-Flanks结构是一种替代传统QFN/DFN类封装形式的新结构工艺,其工艺产品本身具有一定性能优势,并且随着其技术应用的拓展,传统封装产品结构变得多样化。本文针对Wettable-Flanks产品的结构设计以及工艺设计发展方向进行了研究,... Wettable-Flanks结构是一种替代传统QFN/DFN类封装形式的新结构工艺,其工艺产品本身具有一定性能优势,并且随着其技术应用的拓展,传统封装产品结构变得多样化。本文针对Wettable-Flanks产品的结构设计以及工艺设计发展方向进行了研究,分析了Wettable-Flanks产品的性能优势。 展开更多
关键词 Wettable-flanks 汽车电子器件 自动视觉检查(AVI) 可靠性
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Effects of tool flank wear on orthogonal cutting process of aluminum alloy
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作者 袁平 柯映林 《中国有色金属学会会刊:英文版》 CSCD 2006年第A03期1562-1569,共8页
The tool flank begins to wear out as soon as cutting process proceeds. Cutting parameters such as cutting forces and cutting temperature will vary with increasing degree of flank wear. In order to reveal the relations... The tool flank begins to wear out as soon as cutting process proceeds. Cutting parameters such as cutting forces and cutting temperature will vary with increasing degree of flank wear. In order to reveal the relationship between them, the theoretical situations of cutting process were analyzed considering the tool flank wear effect. The variation rules of cutting force, residual stress and temperature distributions along with the tool flank wear were analyzed comparing with the sharp tool tip. Through FEM simulation method, affections of the tool flank wear value VB on cutting forces, residual stress and temperature distributions were analyzed. A special result in this simulation is that the thrust force is more sensitive to tool flank wear, which can be used as a recognition method of tool condition monitoring. The FEM simulation analysis result agrees well with the experimental measuring data in public literatures and some experiments made also by the authors. 展开更多
关键词 铝合金 金属切割 有限元分析 切割温度 应力分析
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Global optimization of tool path for five-axis flank milling with a cylindrical cutter 被引量:23
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作者 DING Han1 & ZHU LiMin2 1 State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 2 School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第8期2449-2459,共11页
In this paper, optimum positioning of cylindrical cutter for five-axis flank milling of non-developable ruled surface is addressed from the perspective of surface approximation. Based on the developed interchangeabili... In this paper, optimum positioning of cylindrical cutter for five-axis flank milling of non-developable ruled surface is addressed from the perspective of surface approximation. Based on the developed interchangeability principle, global optimization of the five-axis tool path is modeled as approximation of the tool envelope surface to the data points on the design surface following the minimum zone criterion recommended by ANSI and ISO standards for tolerance evaluation. By using the signed point-to-surface distance function, tool path plannings for semi-finish and finish millings are formulated as two constrained optimization problems in a unified framework. Based on the second order Taylor approximation of the distance function, a sequential approximation algorithm along with a hierarchical algorithmic structure is developed for the optimization. Numerical examples are presented to confirm the validity of the proposed approach. 展开更多
关键词 FIVE-AXIS flank milling TOOL path OPTIMIZATION TOOL axis trajectory SURFACE SURFACE approximation distance function MINIMAX OPTIMIZATION
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Prediction of cutting forces in flank milling of parts with non-developable ruled surfaces 被引量:6
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作者 Liping WANG Hao SI Liheng GU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第7期1788-1796,共9页
Predicting the cutting forces required for five-axis flank milling is a challenging task due to the difficulties involved in determining the Undeformed Chip Thickness(UCT) and CutterWorkpiece Engagement(CWE). To solve... Predicting the cutting forces required for five-axis flank milling is a challenging task due to the difficulties involved in determining the Undeformed Chip Thickness(UCT) and CutterWorkpiece Engagement(CWE). To solve these problems, this paper presents a new mechanistic cutting force model based on the geometrical analysis of a flank milling process. In the model,the part feature and corresponding cutting location data are taken as input information. The UCT considering cutter runout is calculated according to the instantaneous feed rate of the element cutting edges. A solid-discrete-based method is used to precisely and efficiently identify the CWE between the end mill and the surface being machined. Then, after calibrating the specific force coef-ficients, the mechanistic milling force can be obtained. During the validation process, two practical operations, three-axis flank milling of a vertical surface and five-axis flank milling of a nondevelopable ruled surface, are conducted. Comparisons between predicted and measured cutting forces demonstrate the reliability of the proposed cutting force model. 展开更多
关键词 Chip thickness CUTTING force FIVE-AXIS flank MILLING MACHINING Ruled surface
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