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基于弧段标记的交通网络时间最短路径算法 被引量:4
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作者 高松 陆锋 《地球信息科学》 CSCD 2008年第5期604-610,共7页
标号算法是经典的最短路径算法之一,在交通领域中具有广泛的应用。在交通领域中,时间最短路径比距离最短路径更有意义,而时间最短路径不仅与道路的时间权值有关,还与道路之间的转弯阻抗有关。在传统的交通路网抽象方式下,道路抽象为平... 标号算法是经典的最短路径算法之一,在交通领域中具有广泛的应用。在交通领域中,时间最短路径比距离最短路径更有意义,而时间最短路径不仅与道路的时间权值有关,还与道路之间的转弯阻抗有关。在传统的交通路网抽象方式下,道路抽象为平面图中的弧段,道路间的交叉口抽象为节点。本文介绍了一种适用于传统交通路网模型的弧段标记时间最短路径算法,详细阐述了该算法的原理、数据基础与运行结构。通过分析和实例测试表明,该算法可以顾及城市路网在路口的交通限行与转弯延迟的影响,并且时间复杂度低,具有一定的实际应用价值。 展开更多
关键词 标号算法 段标记 时间最短 转弯延迟
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高效液相色谱-串联质谱法结合稳定同位素标记肽段同时测定稻米及其制品中3种过敏蛋白质 被引量:5
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作者 杨欢 曹赵云 +1 位作者 马有宁 陈铭学 《色谱》 CAS CSCD 北大核心 2021年第12期1314-1323,共10页
基于稳定同位素标记特征肽段和液相色谱-质谱联用仪建立稻米及制品中3种过敏蛋白质的同时定量方法。稻米及制品样品经盐溶液提取,赖氨酰基内切酶(Lys-C)和胰蛋白酶依次水解,C18-SD柱净化后,采用纳升高效液相色谱-线性离子阱-静电场轨道... 基于稳定同位素标记特征肽段和液相色谱-质谱联用仪建立稻米及制品中3种过敏蛋白质的同时定量方法。稻米及制品样品经盐溶液提取,赖氨酰基内切酶(Lys-C)和胰蛋白酶依次水解,C18-SD柱净化后,采用纳升高效液相色谱-线性离子阱-静电场轨道阱(NanoLC-LTQ-Orbitrap)采集和Protein Discovery软件鉴定,NCBI和Uniprot数据库的基本局部搜索比对工具(BLAST)筛选验证,最终获得表征稻米及制品中α-淀粉酶/胰蛋白酶抑制剂类蛋白质(seed allergenic protein RAG2,RAG2)、乙二醛酶Ⅰ活性蛋白(glyoxalaseⅠ)和α-球蛋白(19 kDa globulin)3种过敏蛋白质的特异性肽段。3个特异性肽段经液相色谱梯度洗脱,在Poroshell色谱柱上实现完全分离,由三重四极杆质谱仪分析。实验通过优化多反应监测(MRM)质谱参数,比较不同溶剂体系、水解酶种类和酶量等酶解条件,结合内标法定量,实现对稻米及制品中3种蛋白质的绝对定量。实验结果表明,当酶解溶剂中含1 g/L十二烷基硫酸钠,采用Lys-C和胰蛋白酶组合消化策略,可有效提高3种蛋白质的酶切效率至65.7%~97.3%。该方法在1~200 nmol/L范围内线性关系良好,相关系数均大于0.9972,3种蛋白质的检出限和定量限分别为3 mg/kg和10 mg/kg。3种蛋白质在空白稻米制品基质中3个水平下的加标回收率为80.6%~103.7%,日间和日内精密度均小于11.5%。该方法稳定性好,检测灵敏度高,操作简便,在分析各类稻米及制品中3种过敏蛋白质含量具有广泛的应用前景。 展开更多
关键词 液相色谱-串联质谱 特异性肽 稳定同位素标记 酶解条件 过敏蛋白质 稻米
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酶切型稳定同位素标记肽段为内标用于药物代谢酶的绝对定量分析 被引量:6
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作者 刘喜东 丛宇婷 +3 位作者 胡良海 张养军 顾景凯 钱小红 《分析化学》 SCIE EI CAS CSCD 北大核心 2015年第10期1551-1557,共7页
利用带有酶切位点的稳定同位素标记肽段作内标,采取3种方式处理样品,考察了不同的样品处理过程对实验结果准确性的影响。首先合成不同长度的带有酶切位点的肽段,考察其酶解过程,实验结果表明,胰蛋白酶的活性位点具有一定的选择性,最终... 利用带有酶切位点的稳定同位素标记肽段作内标,采取3种方式处理样品,考察了不同的样品处理过程对实验结果准确性的影响。首先合成不同长度的带有酶切位点的肽段,考察其酶解过程,实验结果表明,胰蛋白酶的活性位点具有一定的选择性,最终确定目标肽段两端分别加入3个氨基酸所形成的肽段为内标。分别采用在酶解前加入带酶切位点的稳定同位素标记肽段、不带酶切位点的稳定同位素标记肽段以及在酶解过程后、质谱检测前加入不带酶切位点的稳定同位素标记肽段3种方式处理样品。结果表明,采取第一种方式处理样品的测定结果更接近真实值,相对偏差范围更小,可减小蛋白质绝对定量分析的误差,提高分析结果的重现性。 展开更多
关键词 稳定同位素标记 绝对定量 酶切位点 药物代谢酶
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一种基于连通域标记的纸病检测算法 被引量:9
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作者 赵晓 何立风 +2 位作者 姚斌 高启航 杨云 《中国造纸学报》 CAS CSCD 北大核心 2018年第2期51-56,共6页
提出了一种基于段的连通域标记处理算法,同时对纸病区域进行连通域标记和形状特征值提取,旨在提高纸病检测的准确率和效率。该算法利用纸病区域为简单连通图像的特点,采用段技术实现了纸病区域的标记处理,探讨了在标记处理同时快速统计... 提出了一种基于段的连通域标记处理算法,同时对纸病区域进行连通域标记和形状特征值提取,旨在提高纸病检测的准确率和效率。该算法利用纸病区域为简单连通图像的特点,采用段技术实现了纸病区域的标记处理,探讨了在标记处理同时快速统计与形状特征值计算有关的中间参数的方法,利用标记结果及形状特征值实现了纸病的快速检测。该算法优化了标记处理与形状特征值提取的过程,减少了纸病图像的扫描次数。结果表明,该算法达到了准确、快速的纸病检测效果,且易于扩展到实际的纸病检测系统中。 展开更多
关键词 连通域标记 段标记 形状特征提取 纸病检测
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一种改进的运动目标标记算法
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作者 付宇 许宏丽 谷君 《计算机与数字工程》 2010年第6期128-131,共4页
针对多运动目标跟踪的实时性要求,对运动目标标记的速度要求也越来越高,在区域增长算法和线标记算法的基础上,结合两者的优点,提出一种新的基于链表的二值图像标记算法。该算法对图像进行一次扫描就可以标记出所有的连通区域,而且很好... 针对多运动目标跟踪的实时性要求,对运动目标标记的速度要求也越来越高,在区域增长算法和线标记算法的基础上,结合两者的优点,提出一种新的基于链表的二值图像标记算法。该算法对图像进行一次扫描就可以标记出所有的连通区域,而且很好的解决了一般算法在扫描过程中出现的标记冲突的问题。对各种图像都具有很好的效果,而且算法在速度上也有提高。 展开更多
关键词 二值图像 区域增长 段标记 连通区域
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基于链表的图像连通区域提取算法 被引量:1
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作者 谢祥徐 《数字通信》 2012年第3期34-38,共5页
提出一种基于链表存储的连通区域提取算法。该算法结合段标记法和区域生长法的特点,以目标段为对象,采用链表存储结构。介绍了该算法的基本原理、实现和优化,分析了算法的实验结果,提出了算法的优化方法。实验表明:算法具有较高的效率,... 提出一种基于链表存储的连通区域提取算法。该算法结合段标记法和区域生长法的特点,以目标段为对象,采用链表存储结构。介绍了该算法的基本原理、实现和优化,分析了算法的实验结果,提出了算法的优化方法。实验表明:算法具有较高的效率,对任意形状的连通区域均有良好的鲁棒性,可有效应用于工业在线检测。 展开更多
关键词 连通区域标记算法 段标记 区域生长法 链表存储
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毛细管反相液相色谱-串联质谱用于肽的鉴定和相对定量分析 被引量:3
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作者 厉欣 江新宁 邹汉法 《色谱》 CAS CSCD 北大核心 2008年第2期189-194,共6页
建立了一种基于毛细管反相液相色谱-串联质谱联用技术和质谱峰强度数据处理的肽段鉴定和相对定量分析方法。该方法无需对样品中的肽进行化学标记,在对样品进行反相色谱分离和串联质谱分析后,将二级质谱扫描数据进行蛋白质数据库搜索,获... 建立了一种基于毛细管反相液相色谱-串联质谱联用技术和质谱峰强度数据处理的肽段鉴定和相对定量分析方法。该方法无需对样品中的肽进行化学标记,在对样品进行反相色谱分离和串联质谱分析后,将二级质谱扫描数据进行蛋白质数据库搜索,获得所鉴定肽段的序列、保留时间、质荷比、带电荷数等定性信息;再以此为定位依据,在全扫描质谱数据中提取该肽段对应的离子峰并以该离子峰的峰强度作为定量信息,从而实现对不同样品中的共有肽段进行差异比较分析。以标准蛋白酶解混合肽段为实验对象,以肽段相对强度的相对标准偏差为指标,考察了该方法用于肽段相对定量分析的重现性、检测动态范围以及浓度标准曲线等,为将该方法用于生物样品中内源性肽的差异分析奠定了基础。 展开更多
关键词 液相色谱-质谱联用 标记定量 蛋白质组学
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Discussion on AFLP Molecular Markers in Piper methysticum and Pepper 被引量:2
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作者 施江 辛莉 +1 位作者 杨彦 郑学勤 《Agricultural Science & Technology》 CAS 2007年第3期5-10,19,共7页
The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 mate... The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 materials of P. methysticum, 21 maerials of cultivated and wild Pepper, 1 material of Peperomia pellucida belonged to different genus. Premiers with good band-type and high polymorphism and resolution were selected from 64 pairs of primers for AFLP amplification and the clustering analysis was conducted with MVSP3.13f software. 191 bands were amplified by 4 pairs of premiers, 189 of which had polymorphism, being 98.6%. 28 germplasms were classified into 6 different groups at the genetic similarity coefficient of 0.52 by silver staining AFLP, in which 6 materials of Piper methysticum were clustered into a single group, indicating that P. methysticum belonged to Pepper family of Pepper genus but were distantly related to the others. The research provided the basis for selecting rootstocks for P. methysticum graft, molecular identification of P. methysticum and the fingerprint construction of P. methysticum. 展开更多
关键词 Piper methysticum PEPPER Amplified fragment length polymorphism
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Microwave induced mutagenesis of Lactobacillus casei subsp. rhamnosus for enhancing L-lactic acid production
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作者 徐伟 王鹏 +3 位作者 张兴 张悦 林海龙 施雪华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第5期673-677,共5页
Mutagenesis of Lactobacillus casei subsp, rhamnosus Xl-12 after low power microwave irradiation was investigated. Under a microwave power of 400 W and irradiation length of 3 min, a mutated strain W4-3-9 with high-yie... Mutagenesis of Lactobacillus casei subsp, rhamnosus Xl-12 after low power microwave irradiation was investigated. Under a microwave power of 400 W and irradiation length of 3 min, a mutated strain W4-3-9 with high-yield L-lactic acid was obtained by screening. Compared with the starting strain X1-12, the L-lactic acid production of W4-3-9 was increased by 58.0% at a concentration of 115.8 g/L. The strain maintained the capability of producing a high L-lactic acid level after 10 generations. Cell surface morphology and DNA structures of parental and mutated strains were observed by atomic force microscopy ( AFM ). Amplified fragment length polymorphism (AFLP) analysis suggested the difference in AFLP band pattern between the mutated and non-mutated strains. Sequencing and BLAST analysis revealed that the catalytic site of lactate dehydrogenase (DHL) was changed due to the microwave induced mutation. 展开更多
关键词 microwave irradiation LACTOBACILLUS L-lactic acid AFM AFLP
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The use of the greater trochanter marker in the thigh segment model:Implications for hip and knee frontal and transverse plane motion
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作者 Valentina Graci Gretchen B.Salsich 《Journal of Sport and Health Science》 SCIE 2016年第1期95-100,共6页
Background:The greater trochanter marker is commonly used in 3-dimensional(3D) models;however,its influence on hip and knee kinematics during gait is unclear.Understanding the influence of the greater trochanter marke... Background:The greater trochanter marker is commonly used in 3-dimensional(3D) models;however,its influence on hip and knee kinematics during gait is unclear.Understanding the influence of the greater trochanter marker is important when quantifying frontal and transverse plane hip and knee kinematics,parameters which are particularly relevant to investigate in individuals with conditions such as patellofemoral pain,knee osteoarthritis,anterior cruciate ligament(ACL) injury,and hip pain.The aim of this study was to evaluate the effect of including the greater trochanter in the construction of the thigh segment on hip and knee kinematics during gait.Methods:3D kinematics were collected in 19 healthy subjects during walking using a surface marker system.Hip and knee angles were compared across two thigh segment definitions(with and without greater trochanter) at two time points during stance:peak knee flexion(PKF) and minimum knee flexion(Min KF).Results:Hip and knee angles differed in magnitude and direction in the transverse plane at both time points.In the thigh model with the greater trochanter the hip was more externally rotated than in the thigh model without the greater trochanter(PKF:-9.34°± 5.21° vs.1.40°± 5.22°,Min KF:-5.68°± 4.24° vs.5.01°± 4.86°;p < 0.001).In the thigh model with the greater trochanter,the knee angle was more internally rotated compared to the knee angle calculated using the thigh definition without the greater trochanter(PKF:14.67°± 6.78° vs.4.33°± 4.18°,Min KF:10.54°± 6.71° vs.-0.01°± 2.69°;p < 0.001).Small but significant differences were detected in the sagittal and frontal plane angles at both time points(p < 0.001).Conclusion:Hip and knee kinematics differed across different segment definitions including or excluding the greater trochanter marker,especially in the transverse plane.Therefore when considering whether to include the greater trochanter in the thigh segment model when using a surface markers to calculate 3D kinematics for movement assessment,it is important to have a clear understanding of the effect of different marker sets and segment models in use. 展开更多
关键词 3D motion analysis Thigh segment model Transverse plane motion
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Preliminary genetic linkage map of the abalone Haliotis diversicolor Reeve
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作者 石耀华 郭希明 +2 位作者 顾志峰 王爱民 王嫣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期549-557,共9页
Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596... Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596 AFLP markers were obtained from 28 primer combinations in two parents and 78 offsprings. Among them, 412 markers (15.9%) were polymorphic and segregated in the mapping family. Chi-square tests showed that 151 (84.4%) markers segregated according to the expected 1:1 Mendelian ratio (P<0.05) in the female parent, and 200 (85.8%) in the male parent. For the female map, 179 markers were used for linkage analysis and 90 markers were assigned to 17 linkage groups with an average interval length of 25.7 cm. For the male map, 233 markers were used and 94 were mapped into 18 linkage groups, with an average interval of 25.0 cm. The estimated genome length was 2 773.0 cm for the female and 2 817.1 cm for the male map. The observed length of the linkage map was 1 875.2 cm and 1 896.5 cm for the female and male maps, respectively. When doublets were considered, the map length increased to 2 152.8 cm for the female and 2 032.7 cm for the male map, corresponding to genome coverage of 77.6% and 72.2%, respectively. 展开更多
关键词 amplification fragment length polymorphism (AFLP) genetic linkage map Haliotis diversicolor Reeve
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Rapid and Sensitive Identification of Horse and Donkey Meat in Iraqi Markets Using SSR and PCR-RFLP Based on Mitochondrial DNA Cytochrome B Gene 被引量:3
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作者 Talib Ahmed Jaayid 《Journal of Agricultural Science and Technology(A)》 2013年第11期896-903,共8页
This study was carried out at the Genetic Engineering Lab, College of Agriculture, University of Basrah. DNA was extracted from samples containing meat of commercial products in the Basrah markets. The products subjec... This study was carried out at the Genetic Engineering Lab, College of Agriculture, University of Basrah. DNA was extracted from samples containing meat of commercial products in the Basrah markets. The products subjected to analysis using polymerase chain reaction (PCR) with species specific repeat (SSR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques based on the sequence of the mitochondrial DNA cytochrome b gene (mtDNA cyt b gene). Then digestion with the Alu l restriction enzyme to establish a differential diagnosis detects and discriminates between meat species and adulteration in the products. SSR primers were applied, has been detected amplification of the encoded gene product, generated 221 bp in some imported minced and canned meat samples. The results show that SSR analysis produced a pattern that allowed a direct identification of horse and donkey meats in some imported minced and canned meat samples (Hana, Monde and Bavaria). The amplified 359 bp gene of mtDNA cyt b gene from samples in different product was cut using Alu 1 restriction enzyme resulting in restriction fragment length polymorphism (RFLP). Alu 1 was used to distinguish between the animals meat that belong to the family or one species. The digestion of the PCR product showed differences between products. Where the fragment length generated were 74, 76 and 189 bp. It belonged to horse meat. The fraud was detected in Hana, Monde and Bavaria products available in Basrah markets showing the presence of horse meat in these products that labeled as beef meats 100%. This revealed mtDNA cyt b gene as highly conserved and consequently a good molecular marker for diagnostic studies. Thus, this technique can be applied to food authentication for the identification of different species of animals in food products. 展开更多
关键词 Polymerase chain reaction SSR RFLP farm animal meats identification adulteration.
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Exploring genetic diversity in Northeastern Sika deer population (Cervus nippon hortulorum) by AFLP molecular markers
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作者 CAI Zhi-hua JIANG De-mei +3 位作者 LUO An-cai TAO Hong-mei HAN Li WEN Xin-fu 《Journal of Life Sciences》 2009年第9期54-61,共8页
The genetic diversity of 27 different Cervus nippon hortulorum was studied to provide theoretical evidence for their identification and utilization. The genomie DNA of 27 different Cereus nippon hortulorum were analyz... The genetic diversity of 27 different Cervus nippon hortulorum was studied to provide theoretical evidence for their identification and utilization. The genomie DNA of 27 different Cereus nippon hortulorum were analyzed by amplified fragment length polymorphism (AFLP). 11,443 bands associated with genetic polymorphism among total 15,169 bands were obtained with 9 kinds of primer pairs and restriction endonuclease EcoRI/Msel, percentage of polymorphie band was 78.43%, 1,271 polymorphic locus were shown per primer pair. The AFLP data showed that average genetic similarity was 0.7841 (0.6809-0.8648). 27 samples were classified into Group I and Group II with cluster analysis, and Group II was divided into five subgroups. The result of AFLP and cluster analysis concluded that there was high genetic variation, which associated with orientated artificial breed selection and breeding in the population. Genetic similarity of Group II-4 was the highest, more than 0.82, while genetic distance in this group was the shortest, from 0.1354 to 0.1563, which was coordinated with breeding record. All these showed that there was great genetic polymorphism among the deer population. The results laid the foundation for main quantitative trait locus (QTLs) of Cervus nippon hortulorum. 展开更多
关键词 Cervus nippon hortulorum population genetic structure AFLP genetic polymorphism
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Genetic Diversity Analysis of Cultured Populations of Jade Perch (Scortum bacoo) in China Using AFLP Markers 被引量:2
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作者 K. C. Chen L. S. Ma Y. Shi J. Zhao X. P. Zhu 《Journal of Agricultural Science and Technology》 2011年第4期455-461,共7页
Genetic diversity of three cultured populations of jade perch (Scortum bacoo) are studied using amplified fragment length polymorphism (AFLP) markers, which is Guangzhou(GZ) population, Foshan (FS) population ... Genetic diversity of three cultured populations of jade perch (Scortum bacoo) are studied using amplified fragment length polymorphism (AFLP) markers, which is Guangzhou(GZ) population, Foshan (FS) population and Qingdao(QD) population. Nine primer combinations were used and 385 fragments were detected. Among the 385 fragments, 80 bands (20.78%) were polymorphic. And it can be speculated that the genetic diversity of the three cultured populations of jade perch was very poor according to the gene genetic diversity among populations (Ht), the gene genetic diversity within populations (Hs) and Shannon-Weiner index (I). From gene differentiation (Gst), genetic distance (D), genetic similarity (5), and UPGMA analysis, it is found that the relationship among the three populations is very closed, and the difference in genetic diversity among the three populations is not significant. Further clustering relationships of the jade perch cultured populations also are correlated to historical-breeding observations and genetic relationships. The GZ population clustered together with the QD population first, then with FS population. 展开更多
关键词 AFLP Scortum bacoo cultured populations genetic diversity.
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