Pectin is a major constituent of the plant cell wall.Pectate lyase(PEL,EC 4.2.2.2)uses anti-β-elimination chemistry to cleave theα-1,4 glycosidic linkage in the homogalacturonan region of pectin.However,limited info...Pectin is a major constituent of the plant cell wall.Pectate lyase(PEL,EC 4.2.2.2)uses anti-β-elimination chemistry to cleave theα-1,4 glycosidic linkage in the homogalacturonan region of pectin.However,limited information is available on the comprehensive and evolutionary analysis of PELs in the Malvaceae.In this study,we identified 597PEL genes from 10 Malvaceae species.Phylogenetic and motif analyses revealed that these PELs are classified into six subfamilies:Clades I,II,III,IV,Va,and Vb.The two largest subfamilies,Clades I and II,contained 237 and222 PEL members,respectively.The members of Clades Va and Vb only contained four or five motifs,far fewer than the other subfamilies.Gene duplication analysis showed that segmental duplication played a crucial role in the expansion of the PEL gene family in Gossypium species.The PELs from Clades I,IV,Va,and Vb were expressed during the fiber elongation stage,but nearly all PEL genes from Clades II and III showed no expression in any of the investigated fiber developmental stages.We further performed single-gene haplotype association analysis in 2,001G.hirsutum accessions and 229 G.barbadense accessions.Interestingly,14 PELs were significantly associated with fiber length and strength traits in G.barbadense with superior fiber quality,while only eight GhPEL genes were found to be significantly associated with fiber quality traits in G.hirsutum.Our findings provide important information for further evolutionary and functional research on the PEL gene family members and their potential use for fiber quality improvement in cotton.展开更多
采用软件Primer premier 5设计引物,从麻类脱胶高效菌株DCE01中克隆出一个果胶酶基因Pel325,重组到表达载体p ET-28a中,在E.coli BL21(DE3)中成功表达。试验结果显示,酶的活性随着底物(橘子果胶)酯化程度的增加而增加。胞内酶用酯化程度...采用软件Primer premier 5设计引物,从麻类脱胶高效菌株DCE01中克隆出一个果胶酶基因Pel325,重组到表达载体p ET-28a中,在E.coli BL21(DE3)中成功表达。试验结果显示,酶的活性随着底物(橘子果胶)酯化程度的增加而增加。胞内酶用酯化程度≥85%的橘子果胶作底物检测时酶活最高(酶活为37.5U/ml),其最适反应温度为55℃,最适反应p H为8.0。该结果可为进一步发掘DCE01菌株的基因资源提供重要科学依据。展开更多
Motion estimation is an important and intensive task in video coding applications. Since the complexity of integer pixel search has been greatly reduced by the numerous fast ME algorithm, the computation overhead requ...Motion estimation is an important and intensive task in video coding applications. Since the complexity of integer pixel search has been greatly reduced by the numerous fast ME algorithm, the computation overhead required by fractional pixel ME has become relatively significant. To reduce the complexity of the fractional pixel ME algorithm, a directionality-based fractional pixel ME algorithm is proposed. The proposed algorithm efficiently explores the neighborhood positions which with high probability to be the best matching around the minimum one and skips over other unlikely ones. Thus, the proposed algorithm can complete the search by examining only 3 points on appropriate condition instead of 17 search points in the search algorithm of reference software. The simulation results show that the proposed algorithm successfully optimizes the fractional-pixel motion search on both half and quarter-pixel accuracy and improves the processing speed with low PSNR penalty.展开更多
We present a theoretical investigation of rotating electroosmotic flows(EOFs) in soft parallel plate microchannels. The soft microchannel, also called as the polyelectrolyte-grafted microchannel, is denoted as a rigid...We present a theoretical investigation of rotating electroosmotic flows(EOFs) in soft parallel plate microchannels. The soft microchannel, also called as the polyelectrolyte-grafted microchannel, is denoted as a rigid microchannel coated with a polyelectrolyte layer(PEL) on its surface. We compare the velocity in a soft microchannel with that in a rigid one for different rotating frequencies and find that the PEL has a trend to lower the velocities in both directions for a larger equivalent electrical double layer(EDL) thickness λFCL(λFCL = 0.3) and a smaller rotating frequency ω(ω < 5).However, for a larger rotating frequency ω(ω = 5), the main stream velocity u far away from the channel walls in a soft microchannel exceeds that in a rigid one. Inspired by the above results, we can control the EOF velocity in micro rotating systems by imparting PELs on the microchannel walls, which may be an interesting application in biomedical separation and chemical reaction.展开更多
基金supported by the Ministry of Agriculture and Rural Affairs,China(2023ZD04039-01)the National Natural Science Foundation of China(32172008)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang,China(2019R01002)。
文摘Pectin is a major constituent of the plant cell wall.Pectate lyase(PEL,EC 4.2.2.2)uses anti-β-elimination chemistry to cleave theα-1,4 glycosidic linkage in the homogalacturonan region of pectin.However,limited information is available on the comprehensive and evolutionary analysis of PELs in the Malvaceae.In this study,we identified 597PEL genes from 10 Malvaceae species.Phylogenetic and motif analyses revealed that these PELs are classified into six subfamilies:Clades I,II,III,IV,Va,and Vb.The two largest subfamilies,Clades I and II,contained 237 and222 PEL members,respectively.The members of Clades Va and Vb only contained four or five motifs,far fewer than the other subfamilies.Gene duplication analysis showed that segmental duplication played a crucial role in the expansion of the PEL gene family in Gossypium species.The PELs from Clades I,IV,Va,and Vb were expressed during the fiber elongation stage,but nearly all PEL genes from Clades II and III showed no expression in any of the investigated fiber developmental stages.We further performed single-gene haplotype association analysis in 2,001G.hirsutum accessions and 229 G.barbadense accessions.Interestingly,14 PELs were significantly associated with fiber length and strength traits in G.barbadense with superior fiber quality,while only eight GhPEL genes were found to be significantly associated with fiber quality traits in G.hirsutum.Our findings provide important information for further evolutionary and functional research on the PEL gene family members and their potential use for fiber quality improvement in cotton.
文摘Motion estimation is an important and intensive task in video coding applications. Since the complexity of integer pixel search has been greatly reduced by the numerous fast ME algorithm, the computation overhead required by fractional pixel ME has become relatively significant. To reduce the complexity of the fractional pixel ME algorithm, a directionality-based fractional pixel ME algorithm is proposed. The proposed algorithm efficiently explores the neighborhood positions which with high probability to be the best matching around the minimum one and skips over other unlikely ones. Thus, the proposed algorithm can complete the search by examining only 3 points on appropriate condition instead of 17 search points in the search algorithm of reference software. The simulation results show that the proposed algorithm successfully optimizes the fractional-pixel motion search on both half and quarter-pixel accuracy and improves the processing speed with low PSNR penalty.
基金Project supported by the National Natural Science Foundation of China(Nos.11772162 and11472140)the Inner Mongolia Autonomous Region Grassland Talent(No.12000-12102013)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(No.2016MS0106)
文摘We present a theoretical investigation of rotating electroosmotic flows(EOFs) in soft parallel plate microchannels. The soft microchannel, also called as the polyelectrolyte-grafted microchannel, is denoted as a rigid microchannel coated with a polyelectrolyte layer(PEL) on its surface. We compare the velocity in a soft microchannel with that in a rigid one for different rotating frequencies and find that the PEL has a trend to lower the velocities in both directions for a larger equivalent electrical double layer(EDL) thickness λFCL(λFCL = 0.3) and a smaller rotating frequency ω(ω < 5).However, for a larger rotating frequency ω(ω = 5), the main stream velocity u far away from the channel walls in a soft microchannel exceeds that in a rigid one. Inspired by the above results, we can control the EOF velocity in micro rotating systems by imparting PELs on the microchannel walls, which may be an interesting application in biomedical separation and chemical reaction.
