37 resultados para Kepler map
Resumo:
We have made a complete set of painting probes for the domestic horse by degenerate oligonucleotide-primed PCR amplification of flow-sorted horse chromosomes. The horse probes, together with a full set of those available for human, were hybridized onto metaphase chromosomes of human, horse and mule. Based on the hybridization results, we have generated genome-wide comparative chromosome maps involving the domestic horse, donkey and human. These maps define the overall distribution and boundaries of evolutionarily conserved chromosomal segments in the three genomes. Our results shed further light on the karyotypic relationships among these species and, in particular, the chromosomal rearrangements that underlie hybrid sterility and the occasional fertility of mules.
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Cross-species chromosome painting with probes derived from flow-sorted dog and human chromosomes was used to construct a high-resolution comparative map for the pig. In total 98 conserved autosomal segments between pig and dog were detected by probes specific for the 38 autosomes and X Chromosome of the dog. Further integration of our results with the published human-dog and cat-dog comparative maps, and with data from comparative gene mapping, increases the resolution of the current pig-human comparative map. It allows for the conserved syntenies detected in the pig, human, and cat to be aligned against the putative ancestral karyotype of eutherian mammals and for the history of karyotype evolution of the pig lineage to be reconstructed. Fifteen fusions, 17 fissions, and 23 inversions are required to convert the ancestral mammalian karyotype into the extant karyotype of the pig.
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Epigenetic regulation in insects may have effects on diverse biological processes. Here we survey the methylome of a model insect, the silkworm Bombyx mori, at single-base resolution using Illumina high-throughput bisulfite sequencing (MethylC-Seq). We conservatively estimate that 0.11% of genomic cytosines are methylcytosines, all of which probably occur in CG dinucleotides. CG methylation is substantially enriched in gene bodies and is positively correlated with gene expression levels, suggesting it has a positive role in gene transcription. We find that transposable elements, promoters and ribosomal DNAs are hypomethylated, but in contrast, genomic loci matching small RNAs in gene bodies are densely methylated. This work contributes to our understanding of epigenetics in insects, and in contrast to previous studies of the highly methylated genomes of Arabidopsis(1) and human(2), demonstrates a strategy for sequencing the epigenomes of organisms such as insects that have low levels of methylation.
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Male and female heroin-dependent patients (HDPs) matched with "normal" people were tested on 4 topographical orientation tasks: schematic map-following, map-memory, schematic picture-following, and picture-memory tasks. The results showed that, in general
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Genetic linkage maps were constructed for large yellow croaker Pseudosciaena crocea (Richardson, 1846) using AFLP and microsatellite markers in an F-1 family. Five hundred and twenty-three AFLP markers and 36 microsatellites were genotyped in the parents and 94 F-1 progeny. Among these, 362 AFLP markers and 13 SSR markers followed the 1:1 Mendelian segregation ratio (P > 0.05). The female genetic map contained 181 AFLP and 7 microsatellite markers forming 24 linkage groups spanning 2959.1 cM, while the male map consisted of 153 AFLP and 8 microsatellite markers in 23 linkage groups covering 2205.7 cM. One sex linked marker was mapped to the male map and co-segregated with the AFLP marker agacta355, suggesting an XY-male determination mechanism and this may be useful in the breeding of monosex populations. (c) 2007 Elsevier B.V. All rights reserved.
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Knowledge management is a critical issue for the next-generation web application, because the next-generation web is becoming a semantic web, a knowledge-intensive network. XML Topic Map (XTM), a new standard, is appearing in this field as one of the structures for the semantic web. It organizes information in a way that can be optimized for navigation. In this paper, a new set of hyper-graph operations on XTM (HyO-XTM) is proposed to manage the distributed knowledge resources.HyO-XTM is based on the XTM hyper-graph model. It is well applied upon XTM to simplify the workload of knowledge management.The application of the XTM hyper-graph operations is demonstrated by the knowledge management system of a consulting firm. HyO-XTM shows the potential to lead the knowledge management to the next-generation web.
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本论文采用Logistic Map耦合格子模型对高聚物中特有的环带球晶进行了模拟,所得到的模拟结果与实验结果吻合较好。同时,研究结果能够对实验制备环带球晶样品提供可靠的理论指导。 首先,我们对Logistic Map耦合格子模型及模型中的两个模拟参量μ和ε进行分析,同时结合实验中各种实验条件对聚合物结晶行为的影响,认为Logistic Map的动力学特征与聚合物结晶行为非常相似,并且参量μ与实验中的结晶温度相关,即随温度的升高而减小,而参量ε与实验中影响扩散的因素有关,即随温度的升高而增大、随分子量的增大而减小,并且随样品厚度的增大而增大。我们对模型的整个参数空间进行计算,得到了可以形成环带球晶形貌的参数范围,通过进一步研究发现环带图案的带宽随参量μ的增大而变窄,随参量ε的增大而变宽。上述研究结果与实验中带宽随实验条件的变化规律是一致的。 在得到环带图案的基础上,我们又进一步计算得到了靶状和螺旋状形貌的参量μ和ε的具体取值范围。通过改变μ和ε的参数取值,模拟了环带球晶形貌由靶状过渡到螺旋状的过程,即靶状图案的环带由外层向内层逐渐断裂成较短的条带结构,所有的条带结构呈现出以空间某处为中心团聚在一起的形貌;随后,这种“团聚”的形貌逐渐消失了,空间中小的条带结构的排列呈无序状态。随着参数的进一步变化,短的条带结构变成较长的带状结构,并且这些带状结构的边缘逐渐发生卷曲,最终形成了螺旋状图案。我们还考察了系统初值和耦合方式对上述图案的影响,结果发现,形成环带球晶的参数范围对系统初值没有明显的依赖性,然而靶状和螺旋状图案的分布受初值的影响较大。此外,发现只有采用交替耦合、并考虑长程耦合作用的Logistic Map耦合格子模型才可以得到环带球晶图案。 为了更好地与实验结果进行对比,我们利用Logistic Map耦合格子模型对二维空间中的几种受限体系进行了模拟。(一)对温度梯度场中的环带球晶进行模拟,发现环带球晶在低温处较易成核,向高温处生长,并且,高温处环带的带宽比低温处宽。(二)对格子宽度受限情况进行了模拟,发现随着受限方向的宽度越来越窄,球晶尺寸逐渐变小,相邻两个环带球晶碰撞产生的界线变短,三个相邻环带球晶所形成的界线的交汇点减少。(三)研究了受限边界上的成核作用对狭长格子中环带球晶的影响,结果发现,随着受限边界上成核点密度的不断增加,其形貌转变分为三个不同阶段:①当成核密度稍有增大时,环带球晶数量增加,直径变小;②继续增大边界成核密度,使得大量晶层从受限边界向格子内生长,导致环带球晶的数量减少,直径也减小;③当成核点增加到一定程度时,整个空间中只有极少数由格子内部成核生长且直径非常小的环带球晶,而占主导地位的是由成核点垂直于受限边界生长出的穿透晶层。这些模拟结果均与实验结果相符合。 我们将Logistic Map耦合映象格子模型发展到三维空间格子中,得到了与环带球晶形貌一致的图案,并且其带宽随模拟参量μ的增大而变窄,随ε的增大而变宽。这一规律性结果与二维正方格子的模拟结果是一致的。这一部分的研究结果还表明,边界条件和格子尺寸对模拟结果有显著的影响,周期性边界条件导致在小体积立方格子中只能得到靶状图案;而当格子尺寸很大时,可以得到螺旋状环带球晶的图案。最后,通过调节垂直于薄膜平面方向上的格子数来研究薄膜厚度对环带图案带宽的影响,发现环带的带宽随厚度的增加而变宽,这与实验中环带球晶的带宽随样品厚度的增加而变大的结论是一致的。
Resumo:
P>Common carp (Cyprinus carpio) is an important fish for aquaculture, but genomics of this species is still in its infancy. In this study, a linkage map of common carp based on Amplified Fragment Length Polymorphism (AFLP) and microsatellite (SSR) markers has been generated using gynogenetic haploids. Of 926 markers genotyped, 151 (149 AFLPs, two SSRs) were distorted and eliminated from the linkage analyses. A total of 699 AFLP and 20 microsatellite (SSR) markers were assigned to the map, which comprised 64 linkage groups and covered 5506.9 cM Kosambi, with an average interval distance of 7.66 cM Kosambi. The normality tests on interval map distances showed a non-normal marker distribution. Visual inspection of the map distance distribution histogram showed a cluster of interval map distances on the left side of the chart, which suggested the occurrence of AFLP marker clusters. On the other hand, the lack of an obvious cluster on the right side showed that there were a few big gaps which need more markers to bridge. The correlation analysis showed a highly significant relatedness between the length of linkage group and the number of markers, indicating that the AFLP markers in this map were randomly distributed among different linkage groups. This study is helpful for research into the common carp genome and for further studies of genetics and marker-assisted breeding in this species.
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In this paper, we try to detect the SZ effect in the 2MASS DWT clusters and less bound objects in order to constrain the warm-hot intergalactic medium distribution on large scales by cross-correlation analysis. The results of both observed WMAP and mock SZ effect map indicate that the hot gas distributes from inside as well as outside of the high density regions of galaxy clusters, which is consistent with the results of both observation and hydro simulation. Therefore, the DWT measurement of the cross-correlation would be a powerful tool to probe the missing of baryons in the universe.
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A 3-dimensional non-commutative oscillator with no mass term but with an appropriate momentum-dependent potential admits a conserved Runge-Lenz vector, derived from the dual description in momentum space. The trajectories lie on ellipses. The dynamical symmetry allows for an algebraic determination of the bound-state spectrum and extends to o(4,2). (c) 2010 Elsevier B.V. All rights reserved.
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Photodissociation dynamics Of C2H5SH, i-C-3-H7SH and n-C3H7SH at 243.1 nm were investigated using velocity map ion-imaging method. H-atom photolysis products were detected by a (2 + 1) resonance enhanced ionization scheme. Both the angular distribution and translational energy distribution of the H-atom elimination processes were determined from the ion images of the H-atom products. The experimental results indicate that the H-atom eliminations from these molecules are mainly direct and fast dissociation processes from a repulsive potential energy state. And a more statistical dissociation process that likely occurs oil the ground state via internal conversion has also been observed. Dissociation energies of the S-H bonds are also derived from the H-atom product translational energy distributions. (C) 2002 Elsevier Science B.V. All rights reserved.
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A wear mechanism map of uncoated high-speed steel (HSS) tools was constructed under the conditions of dry-drilling die-cast magnesium alloys. Three wear mechanisms appear in the map based on the microanalysis of drilled HSS tools by SEM, including adhesive wear, abrasive wear and diffusion wear. In the map, there exists a minor wear region which is called "safety zone". This wear mechanism map will be a good reference for choosing suitable drilling parameters when drilling die-cast magnesium alloys.
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Banded spherulite patterns are simulated in two dimensions by means of a coupled logistic map lattice model. Both target pattern and spiral pattern which have been proved to be existent experimentally in banded spherulite are obtained by choosing suitable parameters in the model. The simulation results also indicate that the band spacing is decreased with the increase of parameter mu in the logistic map and increased with the increase of the coupling parameter epsilon, which is quite similar to the results in some experiments. Moreover, the relationship between the parameters and the corresponding patterns is obtained, and the target patterns and spiral patterns are distinguished for a given group of initial values, which may guide the study of banded spherulite.