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1.
Some approaches for location of centroids of quartz grain outlines to increase homology between Fourier amplitude spectra 总被引：2，自引：0，他引：2
The ability to test for similarities and differences among families of shapes by closed-form Fourier expansion is greatly enhanced by the concept of homology. Underlying this concept is the assumption that each term of a Fourier series, when compared to the same term in another series, represents the same thing. A method that ensures homology is one which minimizes the centering error, as reflected in the first harmonic term of the Fourier expansion. The problem is to chose a set of edge points derived from a much larger, but variable, number of edge points such that a valid homologous Fourier series can be calculated. Methods are reviewed and criteria given to define a proper solution. An algorithm is presented which takes advantage of the fact that minimization of the error term can be accomplished by minimizing the distance between the origin of the polar coordinate system in the calculation of the Fourier series and the shape centroid. The use of this algorithm has produced higher quality solutions for quartz grain provenance studies. 相似文献
2.
Dissolved proteins in seawater samples collected from a coastal area of Tokyo Bay, Sagami Bay and a location off the Kuroshio
Current were investigated by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and high
resolution two-dimensional electrophoresis (2-DE). Four to nine protein bands were detected in SDS-PAGE in the apparent molecular
weight (MW) range from 12 kilo Dalton (kDa) to 49 kDa. The 2-DE technique distinguished 10 to 46 protein spots exhibiting
isoelectric point (pI)/MW ranging 4.3–9.2/12–63 kDa. The elecrophoretic patterns were similar between the coastal and pelagic samples, as well
as previously reported patterns from various pelagic areas. The close similarity of electrophoretic mobility on both SDS-PAGE
and 2-DE gels indicates the compositional homogeneity of dissolved proteins in seawater throughout a broad range of marine
environments. Proteinaceous dissolved organic matter (DOM) that was unresolved and smeared staining characteristics on both
SDS-PAGE and 2-DE gels was first observed in Tokyo Bay waters in the present study and its possible sources are discussed.
Although the two protein species, 48 kDa and 39 kDa proteins, have been identified as homologues of Porin P and low molecular
weight-alkaline phosphatase of Pseudomonas aeruginosa PAO1, respectively, four strains of P. aeruginosa and two species of Pseudomonas spp. have been newly identified as the source organisms of these proteins using the N-terminal amino acid sequence data determined in previous studies. 相似文献
3.
A computational canopy volume (CCV) based on airborne laser scanning (ALS) data is proposed to improve predictions of forest biomass and other related attributes like stem volume and basal area. An approach to derive the CCV based on computational geometry, topological connectivity and numerical optimization was tested with sparse-density, plot-level ALS data acquired from 40 field sample plots of 500–1000 m2 located in a boreal forest in Norway. The CCV had a high correspondence with the biomass attributes considered when derived from optimized filtrations, i.e. ordered sets of simplices belonging to the triangulations based on the point data. Coefficients of determination (R2) between the CCV and total above-ground biomass, canopy biomass, stem volume, and basal area were 0.88–0.89, 0.89, 0.83–0.97, and 0.88–0.92, respectively, depending on the applied filtration. The magnitude of the required filtration was found to increase according to an increasing basal area, which indicated a possibility to predict this magnitude by means of ALS-based height and density metrics. A simple prediction model provided CCVs which had R2 of 0.77–0.90 with the aforementioned forest attributes. The derived CCVs always produced complementary information and were mainly able to improve the predictions of forest biomass relative to models based on the height and density metrics, yet only by 0–1.9 percentage points in terms of relative root mean squared error. Possibilities to improve the CCVs by a further analysis of topological persistence are discussed. 相似文献
4.
稀土元素对鲁西铜石、铜井、龙宝山杂岩体的同源性制约 总被引：2，自引：0，他引：2
20世纪80年代,在山东省平邑县发现归来庄大型金矿床,实现了鲁西黄金找矿的重大突破。此后,鲁西相继发现卓家庄、磨坊沟和龙宝山金矿。近年,又在沂南金矿的深部发现新的矿体,鲁西良好的金矿成矿前景引起了地质学界的广泛关注。目前,鲁西发现的金矿床主要分布在铜石、铜井和龙宝山等燕山期杂岩体的附近。这些岩体在成因上有什么关系值得研究。通过对上述岩体稀土元素的地球化学分析,每种岩体不同期次侵入的岩浆岩的稀土元素分布形式和3种岩体综合稀土元素分布形式均呈向右陡倾的弧形线,且配分曲线形态基本相似,都没有明显的Ce、Eu异常,指示了岩体之间存在同源性,均来自深部同一岩浆房。该认识对于指导鲁西黄金找矿具有一定的意义。 相似文献
5.
应用PCR技术扩增16S rRNA基因和amoA(ammonia monooxygenase subunit A)的基因片段,并测定其序列,对一株源于海水养殖水体的高效氨氧化细菌(ammonia-oxidizing bacteria,AOB)进行了系统发育分析。结果表明,经PCR扩增得到了1 098 bp的16S rRNA基因片段和491 bp的amoA基因片段,将其序列用NCBI-Blast软件在GenBank数据库中进行同源性检索后发现,该菌株的16S rRNA基因序列和amoA基因序列分别与亚硝化单胞菌Nitrosomonas sp.NS20的相对应基因片段相似性分别为98.4%和96.7%。在此基础上构建了系统发育树,表明用该菌株的16S rRNA基因片段和amoA基因片段构建的系统发育树均与亚硝化单胞菌属类聚在一起,结合该菌株形态和生理生化特性,鉴定该株氨氧化细菌属亚硝化单胞菌。 相似文献
6.
病程相关蛋白（PR）广泛参与植物对生物和非生物胁迫的应答。采用cDNA末端快速克隆技术,从东方百合（Lilium）杂交品种索邦中克隆了PR1基因,并命名为LhSorPR1。LhSorPR1基因cDNA全长870 bp,5’非翻译区和3’非翻译区的长度分别为47 bp和274 bp。该基因的开放阅读框为549 bp,编码182个氨基酸。成熟的LhSorPR1蛋白（不含信号肽）分子量为18.19 kDa,等电点为5.69。采用同源建模方式构建的LhSorPR1蛋白三维结构与其模板番茄PR1蛋白p14a具有较高的相似性,说明百合PR1蛋白在结构和功能上与其他植物中的PR1蛋白具有较强的保守性。构建pCold Ⅱ-LhSorPR1原核表达,经IPTG诱导后,目的蛋白在大肠杆菌中以包涵体形式成功表达。使用免疫印迹方法对表达的LhSorPR1重组蛋白进行了验证,并对带有His标签的重组蛋白成功进行了纯化。 相似文献
7.
This paper focuses on the problem of calibrating a pinhole camera from images of profile of a revolution. In this paper, the symmetry of images of profiles of revolution has been extensively exploited and a practical and accurate technique of camera calibration from profiles alone has been developed. Compared with traditional techniques for camera calibration, for instance, it may involve taking images of some precisely machined calibration pattern (such as a calibration grid), or edge detection for determining vanish points which are often far from images center or even do not physically exist or calculation of fundamental matrix and Kruppa equations which can be numerically unstable, the method presented here uses just profiles of revolution, which are commonly found in daily life (e. g. bowls and vases), to make the process easier as a result of the reduced cost and increased accessibility of the calibration objects. This paper firstly analyzes the relationship between the symmetry property of profile of revolution and the intrinsic parameters of a camera, and then shows how to use images of profile of revolution to provide enough information for determining intrinsic parameters. During the process, high-accurate profile extraction algorithm has also been used. Finally, results from real data are presented, demonstrating the efficiency and accuracy of the proposed methods. 相似文献
8.
由于非饱和土的渗透系数是基质吸力的函数,使得控制方程带有强非线性的特征,进而使得控制方程的解析求解变得十分困难。同伦分析法对级数基函数和辅助线性算子的选择具有更大的自由性、灵活性,且收敛性的控制和调节更加容易实现,求解强非线性微分方程时在选择线性算子以及辅助参数上具有明显的优势。因此,针对非饱和土固结方程的非线性特征,对于处于地表浅层的非饱和土层,假设孔隙气压力为大气压力,在Richard经验公式与非饱和土一维固结理论的基础上,推导了非饱和一维固结无量纲控制方程;应用同伦分析法,通过选取适当的初始猜测解与辅助参数,将该非线性方程转换为线性的微分方程组并求解得到固结问题的级数解。此外,以压实高岭土为研究对象,在收集相关试验参数基础之上,将由同伦分析法求得的固结问题的近似解析解与有限差分法数值结果相对比,分析结果验证了解析解的正确性。 相似文献
9.
鞍子山超单元中的四个单元，不同程度地发育就位叶理及同源闪长质包体。从早期单元到晚期单元随着就位叶理强度的减弱，同源闪长质包体数量减少，压扁变形程度降低，二者产状一致。同源闪长质包体应变指数ｋ值总体为０＜ｋ＜１，属三轴压扁型应变椭球体，楔形侵入膨胀式就位机制。根据同源闪长质包体应变测量结果，运用Ｘ／Ｒｉ＝Ｙ／Ｒｆ公式计算出鞍子山超单元发生气球膨胀后的体积比初始体积大１．７０倍，岩浆体积横向拓宽了７０％。 相似文献
10.
目的:探讨CT能谱成像在诊断腹部多发病灶同源性中的价值。材料和方法:收集10例经手术病理或随访观察证实的腹部多发病灶患者资料,回顾性分析患者多发病灶,包括肝脏、胃、肾上腺及腹腔淋巴结转移病灶的CT能谱图像。多发病灶的感兴趣区按照直径5mm的圆形选取,用能谱后处理工具行多发病灶的能量衰减曲线、直方图、散点图分析,将三个图像的吻合情况分成基本吻合,部分吻合,不吻合三种情况,比较多发病灶能谱图像的吻合情况,总结规律,对腹部多发病灶的同源性作出评价。结果:发现腹部恶性肿瘤原发灶与多发转移灶的能量衰减曲线、直方图图像基本吻合,散点图部分吻合,提示原发灶和转移灶同源。多发良性病灶如血管瘤、能谱图像也基本吻合,可帮助诊断病灶的同源性。结论:初步判断能谱CT可作为诊断腹部多发病灶同源性的有效工具。 相似文献