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921.
922.
高光谱遥感可以得到更精确与丰富的遥感信息,因此涵盖了各国家的航空、航天以及小范围的地面观测的多个层级与环节,在对地观测遥感领域占有不可取代的地位。但高光谱数据集往往非常庞大,且包含冗余信息,为后续处理带来了不便。该研究选用拉普拉斯特征映射对高光谱数据降维与特征提取,并提出了一种权重朴素贝叶斯分类算法。通过奖励权重的方法对经典朴素贝叶斯分类器进行了改进,利用公开数据对算法进行验证,判别地物信息准确率达到92.7%,相比于传统方法有了大幅度的提高。 相似文献
923.
Willem Jespers Grgory Verdon Jhonny Azuaje Maria Majellaro Henrik Kernen Xerardo García‐Mera Miles Congreve Francesca Deflorian Chris de Graaf Andrei Zhukov Andrew S. Dor Jonathan S. Mason Johan qvist Robert M. Cooke Eddy Sotelo Hugo Gutirrez‐de‐Tern 《Angewandte Chemie (International ed. in English)》2020,59(38):16536-16543
We present a robust protocol based on iterations of free energy perturbation (FEP) calculations, chemical synthesis, biophysical mapping and X‐ray crystallography to reveal the binding mode of an antagonist series to the A2A adenosine receptor (AR). Eight A2AAR binding site mutations from biophysical mapping experiments were initially analyzed with sidechain FEP simulations, performed on alternate binding modes. The results distinctively supported one binding mode, which was subsequently used to design new chromone derivatives. Their affinities for the A2AAR were experimentally determined and investigated through a cycle of ligand‐FEP calculations, validating the binding orientation of the different chemical substituents proposed. Subsequent X‐ray crystallography of the A2AAR with a low and a high affinity chromone derivative confirmed the predicted binding orientation. The new molecules and structures here reported were driven by free energy calculations, and provide new insights on antagonist binding to the A2AAR, an emerging target in immuno‐oncology. 相似文献
924.
925.
毛细管电泳及其质谱联用技术分析重组人促红细胞生成素 总被引:3,自引:0,他引:3
用高效毛细管电泳测定了重组人促红细胞生成素(rhEPO)的微多相性、肽图,同时采用毛细管电泳质谱联用技术鉴定了部分非糖基化胰酶消解片段和O-126糖基化肽的结构。方法简便、快速,适用于rhEPO半成品的质量控制。 相似文献
926.
Eun Jeoung Lee Sunghee Hyun Jaesun Chun Sung Hwa Shin Sang Sun Kang 《Experimental & molecular medicine》2009,41(8):555-568
Fe65 has been characterized as an adaptor protein, originally identified as an expressed sequence tag (EST) corresponding to an mRNA expressed at high levels in the rat brain. It contains one WW domain and two phosphotyrosine interaction/phosphotyrosine binding domains (PID1/PID2). As the neuronal precursor cell expressed developmentally down regulated 4-2 (Nedd4-2) has a putative WW domain binding motif (72PPLP75) in the N-terminal domain, we hypothesized that Fe65 associates with Nedd4-2 through a WW domain interaction, which has the characteristics of E3 ubiquitin-protein ligase. In this paper, we present evidence for the interaction between Fe65 WW domain and Nedd4-2 through its specific motif, using a pull down approach and co-immunoprecipitation. Additionally, the co-localization of Fe65 and Nedd4-2 were observed via confocal microscopy. Co-localization of Fe65 and Nedd4-2 was disrupted by either the mutation of Fe65 WW domain or its putative binding motif of Nedd4-2. When the ubiquitin assay was performed, the interaction of Nedd4-2 (wt) with Fe65 is required for the cell apoptosis and the ubiquitylation of Fe65. We also observed that the ubiquitylation of Fe65 (wt) was augmented depending on Nedd4-2 expression levels, whereas the Fe65 WW domain mutant (W243KP245K) or the Nedd4-2 AL mutant (72PPLP75 was changed to 72APLA75) was under-ubiquitinated significantly. Thus, our observations implicated that the protein-protein interaction between the WW domain of Fe65 and the putative binding motif of Nedd4-2 down-regulates Fe65 protein stability and subcellular localization through its ubiquitylation, to contribute cell apoptosis. 相似文献
927.
Jorge F. Magallanes 《Journal of Chemometrics》2009,23(3):132-138
A new algorithm for sample selection in the field of experimental design is presented. This method was designed for a multivariate data set of samples where the variables' levels are pre‐determined by the system instead of being determined by the practitioner and especially appropriate for non‐symmetrical multivariable space. Symmetrical experimental designs are not applicable in either of the cases. Anyway, this method is also applicable to symmetrical designs. Several tests have been made for symmetrical and non‐symmetrical cases and also about an already treated real case, comparing the new algorithm with others previously known in literature. Its performance has been checked considering several evaluation quality criteria like D‐optimal, A‐optimal, G‐optimal and models error prediction. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
928.
There are several very difficult problems related to genetic or genomic analysis that belong to the field of discrete optimization in a set of all possible orders. With n elements (points, markers, clones, sequences, etc.), the number of all possible orders is n!/2 and only one of these is considered to be the true order. A classical formulation of a similar mathematical problem is the well-known traveling salesperson problem model (TSP). Genetic analogues of this problem include: ordering in multilocus genetic mapping, evolutionary tree reconstruction, building physical maps (contig assembling for overlapping clones and radiation hybrid mapping), and others. A novel, fast and reliable hybrid algorithm based on evolution strategy and guided local search discrete optimization was developed for TSP formulation of the multilocus mapping problems. High performance and high precision of the employed algorithm named guided evolution strategy (GES) allows verification of the obtained multilocus orders based on different computing-intensive approaches (e.g., bootstrap or jackknife) for detection and removing unreliable marker loci, hence, stabilizing the resulting paths. The efficiency of the proposed algorithm is demonstrated on standard TSP problems and on simulated data of multilocus genetic maps up to 1000 points per linkage group. 相似文献
929.
Nano-mechanical mapping by atomic force microscopy has been developed as an useful application to measure mechanical properties of soft materials at nanometer scale.To date,the Hertzian theory was used for analyzing force- distance curves as the simplest model among several contact mechanics between elastic bodies.However,the preexisting methods based on this theory do not consider the adhesive interaction in principle,which cannot be neglected in the ambient condition.A new analytical method was introdu... 相似文献
930.
通过优化定距射击样本采集条件,考察了六四手枪在不同距离(0,2,5,10,15,20,25,30,35,40,45,50,60,80,100,120,140,170,200,300,500,1 000 cm)垂直射击PU布块靶体时相关元素(氯、钾、硫、锑、锡、钡、铅、汞、砷、铁、铜、锌、钛、钙、铑)的区域扫描图,建立了微束X射线荧光光谱(μ-XRF)面扫描技术分析射击样本的方法,并建立了六四手枪射击残留物特征元素分布图形随射击距离而变化的数据模型,同时对所得数据进行了归一化处理。本方法可协助推断射击距离,为涉枪案件的侦查与诉讼提供科学证据。 相似文献