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Molecular Phylogeny of Slow Lorises (Nycticebus) Revealed by D-loop Sequences and Complete Cytochrome b Gene Sequences of Mitochondrial DNA
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作者 陈静华 Paul CRO W +2 位作者 成岛悦雄 张红卫 张亚平 《Zoological Research》 CAS CSCD 北大核心 2004年第4期292-297,共6页
Partial sequences of the D-loop and the complete sequences of cytochrome b gene (1 140 bp) of the slow lorises (genus Nycticebus) were undertaken to investigate evolutionary relationships among species of Nycticebus.S... Partial sequences of the D-loop and the complete sequences of cytochrome b gene (1 140 bp) of the slow lorises (genus Nycticebus) were undertaken to investigate evolutionary relationships among species of Nycticebus.Sequence analysis results consistently provide new taxonomy evidence at the DNA level for supporting Ratajszczak and Groves’ viewpoint that N.intermedus is merely the adult of N.pygmaeus (Ratajszczak,1998;Groves,1971).Phylogenetic analysis was performed by means of the combined data and these two separate sequences data,respectively,by using various methods,supporting the same topology,in which genus Nycticebus was formed of two clusters.The first cluster was composed of N.pygmaeus,and the second cluster of N.coucang.It also could provide a new molecular genetic evidence to support the view that the genus comprises two species:N.coucang and N.pygmaeus. 展开更多
关键词 Nycticebus Mitochondiral DNA Cytochrome b gene d-loop Molecular phylogeny
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The 2-adic complexity of sum sequences of Legendre sequences
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作者 JING Xiaoyan XU Zhefeng FENG Keqin 《纯粹数学与应用数学》 2025年第2期191-199,共9页
Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequenc... Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequence of any k many Legendre sequences and show that the 2-adic complexity of the sum sequences of any k many Legendre sequences reaches the maximum by proving the case of k=2 and 3,which implies that the sum sequences can resist the attack of rational approximation algorithm. 展开更多
关键词 2-adic complexity binary sequences Legendre symbol Legendre sequences
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Non-Abelian Extensions of Rota-Baxter Pre-Lie Algebras and Wells Exact Sequences
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作者 Shuangjian GUO Qun WANG 《Journal of Mathematical Research with Applications》 2025年第4期473-487,共15页
In this paper,we introduce non-abelian cohomology groups and classify the nonabelian extensions of Rota-Baxter pre-Lie algebras in terms of non-abelian cohomology groups.Next,we explore the inducibility of pairs of au... In this paper,we introduce non-abelian cohomology groups and classify the nonabelian extensions of Rota-Baxter pre-Lie algebras in terms of non-abelian cohomology groups.Next,we explore the inducibility of pairs of automorphisms and derive the analog Wells exact sequences under the circumstance of Rota-Baxter pre-Lie algebras.Finally,we discuss the inducibility problem of pairs of automorphisms about an abelian extensions of Rota-Baxter pre-Lie algebras. 展开更多
关键词 Rota-Baxter pre-Lie algebra non-abelian extension Wells exact sequences
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Pig pangenome graph reveals functional features of non‑reference sequences 被引量:1
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作者 Jian Miao Xingyu Wei +6 位作者 Caiyun Cao Jiabao Sun Yuejin Xu Zhe Zhang Qishan Wang Yuchun Pan Zhen Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期956-970,共15页
Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non... Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non-reference sequences(NRSs),which have not been extensively studied.Results In this study,we constructed a pig pangenome graph using 21 pig assemblies and identified 23,831 NRSs with a total length of 105 Mb.Our findings revealed that NRSs were more prevalent in breeds exhibiting greater genetic divergence from the reference genome.Furthermore,we observed that NRSs were rarely found within coding sequences,while NRS insertions were enriched in immune-related Gene Ontology terms.Notably,our investigation also unveiled a close association between novel genes and the immune capacity of pigs.We observed substantial differences in terms of frequencies of NRSs between Eastern and Western pigs,and the heat-resistant pigs exhibited a substantial number of NRS insertions in an 11.6 Mb interval on chromosome X.Additionally,we discovered a 665 bp insertion in the fourth intron of the TNFRSF19 gene that may be associated with the ability of heat tolerance in South-ern Chinese pigs.Conclusions Our findings demonstrate the potential of a graph genome approach to reveal important functional features of NRSs in pig populations. 展开更多
关键词 Heat tolerance Immune ability Non-reference sequences Pig pangenome
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线粒体DNA D-loop区单核苷酸多态性及拷贝数与皮肌炎发病风险关系 被引量:1
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作者 檀紫瑞 张晶晶 +2 位作者 贾园园 彭晨星 赵宇飞 《安徽医科大学学报》 北大核心 2025年第1期130-135,共6页
目的探究线粒体DNA(mtDNA)的D-loop区单核苷酸多态性(SNPs)和mtDNA拷贝数与皮肌炎(DM)发病风险的关系及其影响因素。方法收录74例DM患者和92例健康受试者,从外周血液中提取基因组DNA,利用PCR技术将mtDNA的D-loop区目的片段进行扩增,对... 目的探究线粒体DNA(mtDNA)的D-loop区单核苷酸多态性(SNPs)和mtDNA拷贝数与皮肌炎(DM)发病风险的关系及其影响因素。方法收录74例DM患者和92例健康受试者,从外周血液中提取基因组DNA,利用PCR技术将mtDNA的D-loop区目的片段进行扩增,对产物进行测序;应用高灵敏度活性氧(ROS)检测套件,测定血清ROS水平;采用流式免疫荧光微球技术测定细胞因子白细胞介素(IL)-5、IL-13、干扰素(IFN)-γ、IL-2、IL-6、IL-10、肿瘤坏死因子-α(TNF-α)、IL-4表达水平,使用Wilcoxon秩和检验评估细胞因子与DM风险相关SNPs的潜在相关性;进行实时荧光定量聚合酶链反应(qPCR)分析,测量mtDNA的相对拷贝数。结果DM患者组存在2个与其发病风险有关的多态性变异位点(16304T/C、16519T/C),线粒体D-loop区的等位基因16304C(χ^(2)=4.937,P=0.026)和16519C(χ^(2)=4.405,P=0.036)与DM患者发病风险有关;DM风险相关等位基因16304C与IL-4低表达相关(P=0.016)。DM患者中的mtDNA拷贝数高于对照组(P<0.001)。结论线粒体D-loop区SNPs可能是DM风险的潜在生物标志物,SNPs可能通过影响细胞因子参与DM的发生。DM的mtDNA拷贝数呈现高表达,mtDNA拷贝数的增加可能会导致线粒体功能障碍,从而引发DM的发病。 展开更多
关键词 皮肌炎 d-loop SNPS 细胞因子 ROS mtDNA拷贝数 发病风险
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基于D-loop区和cox1基因序列的江西9个地区草鱼养殖群体遗传多样性分析 被引量:1
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作者 侯佳浩 刘文玉 +7 位作者 吴春林 张明辉 李琳洁 王子予 黄培荧 范洪祥 简少卿 赵大显 《南昌大学学报(理科版)》 2025年第2期198-207,共10页
为评估江西省草鱼(Ctenopharyngodon idellus)养殖群体的种质资源现状,本研究采用线粒体D-loop区(309 bp)与细胞色素C氧化酶I(cox1)基因(527 bp)部分序列,对江西省9个草鱼繁育场(新干XG、吉安JA、峡江XJ、大余DY、宁都ND、瑞昌RC、上栗S... 为评估江西省草鱼(Ctenopharyngodon idellus)养殖群体的种质资源现状,本研究采用线粒体D-loop区(309 bp)与细胞色素C氧化酶I(cox1)基因(527 bp)部分序列,对江西省9个草鱼繁育场(新干XG、吉安JA、峡江XJ、大余DY、宁都ND、瑞昌RC、上栗SL、万载WZ、南昌NC)草鱼养殖群体进行遗传多样性分析。结果显示:D-loop区检测到225个多态性位点,分离出27个单倍型;cox1基因检测到73个多态性位点,分离出9个单倍型。两个标记的遗传多样性参数均处于较低水平:D-loop区单倍型多样性(Hd)0.067~0.515,核苷酸多样性(π)0.00012~0.03138,cox1基因Hd=0~0.331,π=0~0.00797。群体结构分析表明,群体间发生了不同程度的分化。遗传分化系数:D-loop区0~0.04783、cox1基因0~0.18190。分子方差分析(AMOVA)表明遗传变异主要源于群体内(D-loop区98.82%,cox1基因97.87%)。单倍型网络图与邻接法系统发育树均未呈现地理聚类特征,表明江西9个地区草鱼养殖群体遗传多样性较低,群体间分化匮乏。本研究中9个地区草鱼养殖群体遗传多样性背景,可以为江西草鱼种质资源保护与利用提供参考依据。 展开更多
关键词 草鱼 d-loop cox1基因 遗传多样性
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甘肃滩羊体线粒体DNA D-loop区遗传多样性及系统进化分析
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作者 王燕燕 王珂 +5 位作者 徐建峰 石福岳 郭海龙 高登伟 顾玲荣 王胜明 《家畜生态学报》 北大核心 2025年第6期16-20,共5页
为了探讨甘肃滩羊的遗传多样性与母系起源,试验以甘肃环县、景泰县和靖远县的滩羊为研究对象,采用PCR扩增和直接测序法获得滩羊mtDNA D-loop区序列,分析其遗传多样性、遗传结构并构建系统发育树。结果显示,3个滩羊群体共存在7种不同长度... 为了探讨甘肃滩羊的遗传多样性与母系起源,试验以甘肃环县、景泰县和靖远县的滩羊为研究对象,采用PCR扩增和直接测序法获得滩羊mtDNA D-loop区序列,分析其遗传多样性、遗传结构并构建系统发育树。结果显示,3个滩羊群体共存在7种不同长度的mtDNA D-loop区序列,范围为1107~1183 bp,以1182 bp为主;3个群体的A、G、T、C、A+T、C+G平均含量分别为33.24%、14.29%、29.56%、22.88%、62.87%、37.18%,A+T含量明显高于C+G;共有154个变异位点,33种单倍型,3个滩羊群体mtDNA D-loop序列的Hd平均值为0.977,Pi平均值为0.035;系统发育分析显示,41只滩羊分为3个分支,表明甘肃滩羊可能存在3个母系起源。研究认为甘肃滩羊遗传多样性丰富,遗传稳定,存在3个母系起源。 展开更多
关键词 滩羊 mtDNA d-loop 遗传多样性 系统进化
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基于线粒体基因组D-loop区解析项城猪种质特征及遗传多样性
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作者 张开源 王畅 +9 位作者 王冰洁 韩雪蕾 李新建 王腾飞 秦本源 李秀领 余彤 杨峰 柏峻 刘贤 《中国畜牧杂志》 北大核心 2025年第8期213-220,共8页
中国本土猪种质资源正面临外来商品猪种基因渗透导致的遗传资源流失危机。作为河南省重新被发现的地方猪种资源,项城猪的种质特性与遗传背景亟待阐明。本研究通过线粒体DNA D-loop区测序技术对项城猪进行遗传多样性分析,并采用邻接法(Ne... 中国本土猪种质资源正面临外来商品猪种基因渗透导致的遗传资源流失危机。作为河南省重新被发现的地方猪种资源,项城猪的种质特性与遗传背景亟待阐明。本研究通过线粒体DNA D-loop区测序技术对项城猪进行遗传多样性分析,并采用邻接法(Neighbor-Joining,NJ)构建其与6个国内外代表性猪种之间的系统进化关系。结果显示,项城猪群体遗传多样性较高,单倍型多样性(Haplotype Diversity,Hd)为0.833,核苷酸多样性(Nucleotide Diversity,Pi)为0.00311,其遗传多样性水平高于淮南猪(Hd=0.788,Pi=0.00156)、藏猪(Hd=0.705,Pi=0.00283)、莱芜猪(Hd=0.589,Pi=0.00246),与南阳黑猪(Hd=0.815,Pi=0.00360)、五指山猪(Hd=0.838,Pi=0.00334)和保山猪(Hd=0.828,Pi=0.00371)等处于相近水平。项城猪群体共鉴定出14个单倍型,涉及29个多态位点(21个单一变异位点,8个简约信息位点)。其中,项城猪公猪群体展现出更高的单倍型分化(11个单倍型,21个多态位点),表明其公猪群体在维持群体遗传结构中可能发挥重要作用。系统进化树分析显示,项城猪形成一个独立分支,其与河南地方猪种间的遗传距离(Genetic Distance,GD)较近(GD为0.004~0.010),但仍存在一定差异;项城猪与西方外来猪种杜洛克、长白猪之间的遗传距离更远(GD为0.022~0.024),进一步说明项城猪的地方独立性。本研究首次系统揭示了项城猪独特的遗传结构和丰富的遗传多样性,研究成果为项城猪的遗传保护、资源评价及种质创新利用提供了坚实的分子遗传学基础。 展开更多
关键词 项城猪 线粒体DNA d-loop 遗传多样性 系统发育分析 遗传距离
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The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes
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作者 Jianzhong Huang Peng Jia +3 位作者 Xiaoju Zhong Xiuying Guan Hongbin Zhang Honglei Ruan 《American Journal of Molecular Biology》 CAS 2024年第2期54-65,共12页
Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using co... Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes. 展开更多
关键词 Coding sequence Genomic sequence Nicotiana benthamiana Plant Genes
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Phylogenetic, phylogeographic and divergence time analysis of Anopheles subpictus species complex using ITS2 and COI sequences
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作者 Lihini Sandaleka Muthukumarana Methsala Madurangi Wedage +1 位作者 Samanthika Rathnayake Nissanka Kolitha De Silva 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期214-225,I0004-I0038,共47页
Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Tran... Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Transcriber Spacer 2(ITS2)and cytochrome C oxidase I(COI)sequences deposited at the GenBank.Methods:Seventy-five ITS2,210 COI and 26 concatenated sequences available in the NCBI database were used.Phylogenetic analysis was performed using Bayesian likelihood trees,whereas median-joining haplotype networks and time-scale divergence trees were generated for phylogeographic analysis.Genetic diversity indices and genetic differentiation were also calculated.Results:Two genetically divergent molecular forms of An.subpictus species complex corresponding to sibling species A and B are established.Species A evolved around 37-82 million years ago in Sri Lanka,India,and the Netherlands,and species B evolved around 22-79 million years ago in Sri Lanka,India,and Myanmar.Vietnam,Thailand,and Cambodia have two molecular forms:one is phylogenetically similar to species B.Other forms differ from species A and B and evolved recently in the above mentioned countries,Indonesia and the Philippines.Genetic subdivision among Sri Lanka,India,and the Netherlands is almost absent.A substantial genetic differentiation was obtained for some populations due to isolation by large geographical distances.Genetic diversity indices reveal the presence of a long-established stable mosquito population,at mutation-drift equilibrium,regardless of population fluctuations.Conclusions:An.subpictus species complex consists of more than two genetically divergent molecular forms.Species A is highly divergent from the rest.Sri Lanka and India contain only species A and B. 展开更多
关键词 Molecular systematics ITS2 COI DNA sequences Phylogeny PHYLOGEOGRAPHY
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On power series statistical convergence and new uniform integrability of double sequences
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作者 Sevda Y■ld■z Kamil Demirci 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期519-532,共14页
In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p... In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings. 展开更多
关键词 power series methods statistical convergence uniform integrability double sequences
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Feature-driven topology optimization method preserving component sequences considering turning angle constraint
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作者 Dongsheng Jia Lei Liu +2 位作者 Jihong Zhu Yu Zhang Vassili Toropov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2024年第10期41-56,共16页
Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing ... Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing of continuous fibre-reinforcedpolymer structures, customized stents, and soft robotics parts. This study presents a feature-driven method that preservescomponent sequences accounting for engineering requirements. The chain-of-bars design variables setting scheme is developedto realize the sequential component’s layout, which sets the current bar’s end point as the next bar’s start point. The total lengthof the printing path is constrained to reduce the consumption of material accurately. Also, the angle between adjacent bars isconstrained to avoid sharp angles at the turning point of the 3D printing path. Next, the sensitivity analysis considering theinter-dependence of substructures is performed. Several numerical examples are given to demonstrate the validity and merits ofthe proposed method in designing structures preserving component sequences. 展开更多
关键词 Topology optimization Component sequence preservation Chain-like structures Feature-driven method Additive manufacturing
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基于D-loop区多态性分析新疆地区7个哈萨克牛群体遗传结构和母系起源 被引量:1
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作者 王盼盼 沙拉玛提·波代 +2 位作者 巴合提·博代 李振伟 吾热力哈孜·哈孜汗 《中国畜牧兽医》 北大核心 2025年第3期1166-1179,共14页
【目的】利用线粒体DNA(mtNDA)D-loop区序列多态性作为标记,探究新疆7个哈萨克牛群体间遗传结构和母系起源,为新疆黄牛品种合理利用和生物多样性保护提供资料。【方法】采集哈萨克牛血液提取DNA,测定179头哈萨克牛个体mtDNA D-loop序列... 【目的】利用线粒体DNA(mtNDA)D-loop区序列多态性作为标记,探究新疆7个哈萨克牛群体间遗传结构和母系起源,为新疆黄牛品种合理利用和生物多样性保护提供资料。【方法】采集哈萨克牛血液提取DNA,测定179头哈萨克牛个体mtDNA D-loop序列,利用SnapGene软件对所获序列与参考序列进行比对、校正,确定mtDNA D-loop区序列的长度和位置,并统计碱基含量;利用DnaSP 5.10软件统计哈萨克牛种群单核苷酸多态性(SNP)位点,并计算单倍型数(H)、核苷酸多样性(Pi)、单倍型多样度(Hd)等参数;利用Arlequin 3.0软件分析哈萨克牛种群的遗传结构;采用Mega 11.0软件计算mtDNA D-loop区哈萨克牛种群的遗传距离,并构建Neighbor-Joining(NJ)系统进化树。【结果】哈萨克牛群体mtDNA D-loop区全序列长909~911 bp,其A、G、T、C 4种碱基平均含量分别为32.8%、13.8%、28.8%和24.6%,AT含量高于GC含量,179个个体共检测到131个SNPs,其中变异位点占所测核苷酸全长的14.40%,定义了89种单倍型,Hd和Pi分别为0.974和0.01288,表明哈萨克牛群体的遗传多样性十分丰富。分子变异分析结果表明,97.13%的变异属于群体内,2.87%则来自群体间变异,遗传距离为0.0109~0.0186,群体间遗传分化指数(F st)为―0.0053~0.0782,且均无显著分化(P>0.05)。系统发生树显示,新疆地区7个哈萨克牛群体有普通牛和瘤牛两大母系起源。【结论】新疆地区哈萨克牛源于两个母系,遗传多样性丰富。尽管群体间存在遗传分化,但并未形成明显的地理隔离,且遗传结构差异正在缩小。本研究结果为保护和利用哈萨克牛遗传资源提供了理论依据。 展开更多
关键词 哈萨克牛 线粒体DNA d-loop 遗传多样性 系统进化
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Adaptive Successive POI Recommendation via Trajectory Sequences Processing and Long Short-Term Preference Learning
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作者 Yali Si Feng Li +3 位作者 Shan Zhong Chenghang Huo Jing Chen Jinglian Liu 《Computers, Materials & Continua》 SCIE EI 2024年第10期685-706,共22页
Point-of-interest(POI)recommendations in location-based social networks(LBSNs)have developed rapidly by incorporating feature information and deep learning methods.However,most studies have failed to accurately reflec... Point-of-interest(POI)recommendations in location-based social networks(LBSNs)have developed rapidly by incorporating feature information and deep learning methods.However,most studies have failed to accurately reflect different users’preferences,in particular,the short-term preferences of inactive users.To better learn user preferences,in this study,we propose a long-short-term-preference-based adaptive successive POI recommendation(LSTP-ASR)method by combining trajectory sequence processing,long short-term preference learning,and spatiotemporal context.First,the check-in trajectory sequences are adaptively divided into recent and historical sequences according to a dynamic time window.Subsequently,an adaptive filling strategy is used to expand the recent check-in sequences of users with inactive check-in behavior using those of similar active users.We further propose an adaptive learning model to accurately extract long short-term preferences of users to establish an efficient successive POI recommendation system.A spatiotemporal-context-based recurrent neural network and temporal-context-based long short-term memory network are used to model the users’recent and historical checkin trajectory sequences,respectively.Extensive experiments on the Foursquare and Gowalla datasets reveal that the proposed method outperforms several other baseline methods in terms of three evaluation metrics.More specifically,LSTP-ASR outperforms the previously best baseline method(RTPM)with a 17.15%and 20.62%average improvement on the Foursquare and Gowalla datasets in terms of the Fβmetric,respectively. 展开更多
关键词 Location-based social networks adaptive successive point-of-interest recommendation long short-term preference trajectory sequences
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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矮小芦花鸡线粒体DNA D-loop序列变异起源分化研究
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作者 栾祜 缪立生 +2 位作者 柳俭强 陈小辛 张立春 《中国畜牧杂志》 北大核心 2025年第9期227-233,共7页
本研究旨在探索吉林省矮小芦花鸡这一独特地方品种的遗传多样性和母系起源。通过对矮小芦花鸡线粒体DNA D-loop区序列的分析,揭示该品种的遗传结构及其历史演化路径,为有效保护和利用这一珍贵的遗传资源,以及未来的选育和遗传改良工作... 本研究旨在探索吉林省矮小芦花鸡这一独特地方品种的遗传多样性和母系起源。通过对矮小芦花鸡线粒体DNA D-loop区序列的分析,揭示该品种的遗传结构及其历史演化路径,为有效保护和利用这一珍贵的遗传资源,以及未来的选育和遗传改良工作提供坚实的理论基础。本研究以34只矮小芦花鸡为研究对象,针对其线粒体DNA D-loop区域开展PCR扩增、测序及比对分析,系统评估该品种的遗传多样性特征与母系起源。研究获得长度为1 052 bp的D-loop序列,碱基组成分析显示A+T含量(54.4%)显著高于G+C含量(45.6%),呈现出明显的碱基偏向性特征。通过序列比对共检测到21个变异位点,其中包含6个单一变异位点和15个简约信息位点。具体而言,变异类型包括3处单碱基插入事件,所有变异均表现为单碱基替换(20个转换+1个颠换),其中T-C转换14次(占比66.7%)、A-G转换6次(占比28.6%)、A-C颠换1次(占比4.7%)。遗传多样性分析显示:核苷酸多样性(Pi)为0.007 64±0.001 4,单倍型多样性(Hd)达0.872±0.027,平均核苷酸差异数(K)为6.067,表明该群体存在丰富的核苷酸变异。序列分析共鉴定出9种单倍型,单倍型间遗传距离范围为0.001~0.016。系统发育关系重建显示该群体分化为3个独立的线粒体谱系,不仅证实了其存在3个母系起源,更揭示了群体内部个体间遗传距离较近的特性。上述研究结果充分表明矮小芦花鸡具有较高的遗传多样性水平,亟需加强该珍贵地方品种的遗传资源保护与系统性保育工作。 展开更多
关键词 矮小芦花鸡 线粒体DNA d-loop 核苷酸多样性 单倍型多样性 平均核苷酸差异数
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基于线粒体DNA D-loop标记的华南地区4种鲤亚科鱼类遗传多样性分析 被引量:2
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作者 姚东林 张涛 朱静璇 《渔业研究》 2025年第1期11-18,共8页
【目的】研究华南地区鲤亚科鱼类的遗传多样性,为开展淡水鱼类的遗传育种工作提供参考。【方法】本研究采集位于海南省、广东省、广西壮族自治区的华南鲤(Cyprinus car-piorubrofuscus Lacepede)、尖鳍鲤(Cyprinus acutidorsalis Wang)... 【目的】研究华南地区鲤亚科鱼类的遗传多样性,为开展淡水鱼类的遗传育种工作提供参考。【方法】本研究采集位于海南省、广东省、广西壮族自治区的华南鲤(Cyprinus car-piorubrofuscus Lacepede)、尖鳍鲤(Cyprinus acutidorsalis Wang)、三角鲤(Cyprinus multita-eniata Pellegrin et Chevey)和须鲫(Carassioides cantonensis Heincke)4种鲤亚科鱼类的6个种群共156个样本,采用线粒体D-loop标记分析其遗传多样性。【结果】研究结果表明,华南鲤的海南、珠江和榕江3个种群的遗传多样性相对较高,其线粒体控制区的单倍型多样性分别为0.814、0.895和0.879;须鲫、尖鳍鲤和三角鲤的单倍型多样性较低,分别为0.748、0.794和0.536。华南鲤的遗传多样性较高,其中海南种群略低于珠江种群和榕江种群,可能与历史上的冰期活动和琼州海峡的阻隔有关。须鲫、尖鳍鲤和三角鲤三者的遗传多样性相对较低,这可能与3个物种本身的分布范围较小、生存能力较差有关。【意义】本研究结果为进一步探明华南地区鲤亚科鱼类的自然资源状况和开展淡水鱼类的遗传育种工作提供了重要的参考。 展开更多
关键词 华南鲤 尖鳍鲤 三角鲤 须鲫 d-loop 遗传多样性
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鲫属鱼类线粒体D-loop区结构及其系统发育分析
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作者 周益成 邓彬华 +5 位作者 郑鹏 刘兰苑 陈锭娴 林胜跃 蔡国军 李强 《湖南农业科学》 2025年第9期77-82,共6页
鲫属鱼类广泛分布于亚欧地区,由于其外观形态复杂多变,且存在多种倍性和繁殖方式,其分类体系尚未达成共识。本研究采用PCR和基因测序技术,对金鱼、缩骨鲫、彭泽鲫鱼和鲫鱼4种鲫属鱼类线粒体D-loop区进行测序,并与NCBI上已发表的鱼类相... 鲫属鱼类广泛分布于亚欧地区,由于其外观形态复杂多变,且存在多种倍性和繁殖方式,其分类体系尚未达成共识。本研究采用PCR和基因测序技术,对金鱼、缩骨鲫、彭泽鲫鱼和鲫鱼4种鲫属鱼类线粒体D-loop区进行测序,并与NCBI上已发表的鱼类相关序列进行联合对比。结果表明:鲫属鱼类mtDNA D-loop序列长度为919~959 bp,A+T平均含量65.7%,呈现A+T碱基组成偏倚性;种间平均遗传距离为0.002~0.078,金鱼与缩骨鲫、彭泽鲫与方正银鲫D品系之间遗传距离最小,淇河鲫与黑鲫之间的遗传距离最大;基于邻接法构建的系统发育树显示,15种鲫属鱼类聚为4大支系,支系Ⅰ涵盖10种中国本土鲫鱼及选育种,支系Ⅱ为3种日本鲫鱼,支系Ⅲ为白鲫,支系Ⅳ为黑鲫;支系Ⅰ又可分为A、B和C 3个姐妹支系,其中金鱼与缩骨鲫存在较近的亲缘关系,彭泽鲫与银鲫存在较近的亲缘关系。 展开更多
关键词 鲫属鱼类 d-loop 系统发育
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Transcriptional profiling during infection of potato NLRs and Phytophthora infestans effectors using cDNA enrichment sequencing 被引量:1
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作者 Amanpreet Kaur Vikrant Singh +6 位作者 Stephen Byrne Miles Armstrong Thomas M.Adams Brian Harrower Eleanor Gilroy Ewen Mullins Ingo Hein 《The Crop Journal》 2025年第1期31-40,共10页
An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascert... An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascertain at early infection stages owing to the unfavourable transcript representation compared to the host genes.In this study,we compare two sequencing techniques,RNAseq and enrichment sequencing(RenSeq and PenSeq)of cDNA,to investigate gene expression patterns in the doubled monoploid potato(DM)infected with the late blight pathogen Phytophthora infestans.Our results reveal distinct advantages of cDNA RenSeq and PenSeq over traditional RNAseq in terms of target gene representation and transcriptional quantification at early infection stages.Throughout the infection time course,cDNA enrichment sequencing enables transcriptomic analyses for more targeted host and pathogen genes.For highly expressed genes that were sampled in parallel by both cDNA enrichment and RNAseq,a high level of concordance in expression profiles is observed,indicative of at least semi-quantitative gene expression representation following enrichment. 展开更多
关键词 RxLR effector NLRS Late blight POTATO cDNA sequencing RenSeq PenSeq RNASEQ
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Detailed oil-source correlation within the sequence and sedimentary framework in the Fushan Depression,Beibuwan Basin,South China Sea 被引量:1
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作者 Xin Wang Mei-Jun Li +3 位作者 Yang Shi Hao Guo Bang Zeng Xi He 《Petroleum Science》 2025年第1期90-109,共20页
The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nev... The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nevertheless,no systematic investigations on the classification and origin of oils and hy-drocarbon migration processes have been made for the entire petroleum system in this depression,which has significantly hindered the hydrocarbon exploration in the region.A total of 32 mudstone and 58 oil samples from the Fushan Depression were analyzed to definite the detailed oil-source correlation within the sequence and sedimentary framework.The organic matter of third member of Paleogene Liushagang Formation(Els(3))source rocks,both deltaic and lacustrine mudstone,are algal-dominated with high abundance of C_(23)tricyclic terpane and C_(30)4-methylsteranes.The deltaic source rocks occur-ring in the first member(Els_(1))and second member(Els_(2))of the Paleogene Liushagang Formation are characterized by high abundance of C_(19+20)tricyclic terpane and oleanane,reflecting a more terrestrial plants contribution.While lacustrine source rocks of Els_(1)and Els_(2)display the reduced input of terrige-nous organic matter with relatively low abundance of C 19+20 tricyclic terpane and oleanane.Three types of oils were identified by their biomarker compositions in this study.Most of the oils discovered in the Huachang and Bailian Els_(1)reservoir belong to group A and were derived from lacustrine source rocks of Els_(1)and Els_(2).Group B oils are found within the Els_(1)and Els_(2)reservoirs,showing a close relation to the deltaic source rocks of Els_(1)and Els_(2),respectively.Group C oils,occurring in the Els3 reservoirs,have a good affinity with the Els3 source rocks.The spatial distribution and accumulation of different groups of oils are mainly controlled by the sedimentary facies and specific structural conditions.The Els_(2)reservoir in the Yong'an area belonging to Group B oil,are adjacent to the source kitchen and could be considered as the favorable exploration area in the future. 展开更多
关键词 Oil-source correlation sequence stratigraphic framework Biomarkers Fushan depression South China Sea
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