Improved Constraints on D0-D̅0 Mixing in D0→K+π- Decays from the Belle Detector

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歴史的市街地における建築物修景事業に対する助成制度に関する研究 : 東海４県の景観行政団体の運用実態

application/pdf三重大学大学院工学研究科建築学専攻110thesi

<書評>鈴木敏正著, 『地域づくり教育の誕生 : 北アイルランドの実践分析』

rights: 日本教育学会 rights: 本文データは学協会の許諾に基づきCiNiiから複製したものである relation: IsVersionOf: http://ci.nii.ac.jp/naid/110001175996/textapplication/pdfjournal articl

Genomic Islands of Speciation in <em>Anopheles gambiae</em>

<div><p>The African malaria mosquito, <em>Anopheles gambiae</em> sensu stricto <em>(A. gambiae),</em> provides a unique opportunity to study the evolution of reproductive isolation because it is divided into two sympatric, partially isolated subtaxa known as <em>M</em> form and <em>S</em> form. With the annotated genome of this species now available, high-throughput techniques can be applied to locate and characterize the genomic regions contributing to reproductive isolation. In order to quantify patterns of differentiation within <em>A. gambiae</em>, we hybridized population samples of genomic DNA from each form to Affymetrix GeneChip microarrays. We found that three regions, together encompassing less than 2.8 Mb, are the only locations where the <em>M</em> and <em>S</em> forms are significantly differentiated. Two of these regions are adjacent to centromeres, on Chromosomes 2L and X, and contain 50 and 12 predicted genes, respectively. Sequenced loci in these regions contain fixed differences between forms and no shared polymorphisms, while no fixed differences were found at nearby control loci. The third region, on Chromosome 2R, contains only five predicted genes; fixed differences in this region were also verified by direct sequencing. These “speciation islands” remain differentiated despite considerable gene flow, and are therefore expected to contain the genes responsible for reproductive isolation. Much effort has recently been applied to locating the genes and genetic changes responsible for reproductive isolation between species. Though much can be inferred about speciation by studying taxa that have diverged for millions of years, studying differentiation between taxa that are in the early stages of isolation will lead to a clearer view of the number and size of regions involved in the genetics of speciation. Despite appreciable levels of gene flow between the <em>M</em> and <em>S</em> forms of <em>A. gambiae</em>, we were able to isolate three small regions of differentiation where genes responsible for ecological and behavioral isolation are likely to be located. We expect reproductive isolation to be due to changes at a small number of loci, as these regions together contain only 67 predicted genes. Concentrating future mapping experiments on these regions should reveal the genes responsible for reproductive isolation between forms.</p> </div

Differentiation between Forms

<p>The significance threshold shown is <i>p</i> = 0.05, Bonferroni-corrected for the number of windows tested per chromosome. The centromeres of Chromosomes 2 and 3 are located between the right and left arms, i.e., between each pair of graphs; the centromere of Chromosome X is located at the right end of the graph. Grey areas are divergent regions identified by our HMM. The grey region at the tip of Chromosome X appears to lie outside of the final window because the chromosomal position given for each window is the location of the central probe in that window; the final window on Chromosome X spans a large region because of low gene density. Sequenced loci are shown with red triangles; overlapping triangles on Chromosomes 3R and 2R obscure multiple sequenced loci (see text for details). 3L, left arm of Chromosome 3; 3R, right arm of Chromosome 3.</p

Comparative transcriptomics in two bivalve species offers different perspectives on the evolution of sex-biased genes

<div>Comparative genomics has become a central tool for evolutionary biology, and a better knowledge of understudied taxa represents the foundation for future work. In this study we characterized the transcriptome of male and female mature gonads in the European clam <i>Ruditapes decussatus</i>, compared to that in the Manila clam <i>Ruditapes philippinarum</i> providing, for the first time in bivalves, information about transcription dynamics and sequence evolution of sex-biased genes. In both the species we found a relatively low number of sex-biased genes (1,284, corresponding to 41.3 % of the orthologous genes between the two species), probably due to the absence of sexual dimorphism, and the transcriptional bias is maintained in only 33% of the orthologs. The dN/dS is generally low, indicating purifying selection, with genes where the female-biased transcription is maintained between the two species showing a significantly higher dN/dS. Genes involved in embryo development, cell proliferation, and maintenance of genome stability show a faster sequence evolution. Finally, we report a lack of clear correlation between transcription level and evolutionary rate in these species, in contrast with studies that reported a negative correlation. We discuss such discrepancy and call into question some methodological approaches and rationales generally used in this type of comparative studies.<br></div

Systematic Production of Inactivating and Non-Inactivating Suppressor Mutations at the relA Locus That Compensate the Detrimental Effects of Complete spoT Loss and Affect Glycogen Content in Escherichia coli

In Escherichia coli, ppGpp is a major determinant of growth and glycogen accumulation. Levels of this signaling nucleotide are controlled by the balanced activities of the ppGpp RelA synthetase and the dual-function hydrolase/synthetase SpoT. Here we report the construction of spoT null (ΔspoT) mutants obtained by transducing a ΔspoT allele from ΔrelAΔspoT double mutants into relA+ cells. Iodine staining of randomly selected transductants cultured on a rich complex medium revealed differences in glycogen content among them. Sequence and biochemical analyses of 8 ΔspoT clones displaying glycogen-deficient phenotypes revealed different inactivating mutations in relA and no detectable ppGpp when cells were cultured on a rich complex medium. Remarkably, although the co-existence of ΔspoT with relA proficient alleles has generally been considered synthetically lethal, we found that 11 ΔspoT clones displaying high glycogen phenotypes possessed relA mutant alleles with non-inactivating mutations that encoded stable RelA proteins and ppGpp contents reaching 45-85% of those of wild type cells. None of the ΔspoT clones, however, could grow on M9-glucose minimal medium. Both Sanger sequencing of specific genes and high-throughput genome sequencing of the ΔspoT clones revealed that suppressor mutations were restricted to the relA locus. The overall results (a) defined in around 4 nmoles ppGpp/g dry weight the threshold cellular levels that suffice to trigger net glycogen accumulation, (b) showed that mutations in relA, but not necessarily inactivating mutations, can be selected to compensate total SpoT function(s) loss, and (c) provided useful tools for studies of the in vivo regulation of E. coli RelA ppGpp synthetase.journal articl

仮想空間における折り紙の対話型操作の実現

グラフィックスハードウェアの進歩に伴い,グラフィックス環境を用いた人間に親しみやすいヒューマンインタフェースの構築が可能になってきている.CGによるビジュアルな環境を利用すれば,コンピュータ内に定義された仮想空間中の物体を実物と同じように操作することが可能になる.本論文では,仮想空間中に表現された証に対し｢折り曲げ｣｢折り返し｣｢折り込み｣の対話操作が可能な祈り故のシミュレーションシステムを開発したので報告する.オペレ-タはスクリーンモニタに表示された3次元仮想空間内の故をマウスデバイスにより洗面の頂点を摘んで移動する感覚で操作できるので,実物を折るような感覚で仮想の紙を自由に折ることができる.この操作は視点移動により紙をあらゆる方向から観測しながら行うことができ,この操作を繰り返すことにより一枚の紙を複雑な形状に容易に加工できる.また,頂点や辺同士を正確に重ねて折る場合にはそれらの微妙なずれは自動的に補正されるので,実際に紙を折るよりも正確かつ容易に仮想空間の紙を折ることができる.本文ではシステムの実現において特に重要な,誌面の接続や重なり関係等の折り紙の状態を2分木リストにより記述する方法,折り捜査に従ってリストを高遠に変更する方法, マウス入力により3次元空間内にある故の頂点の位定を移動するための工夫などについても述べる.With advance of graphics hardwares, possibility of natural man-machine interface using graphic environments is drawing attention. Visual environments using computer graphics are very effective for virtual object manipulation. This paper describes a visual simulation system.of ORIGAMI (paper folding art) which realizes interactive folding operations of paper such as 'Bending', 'Folding up' and 'Tucking in' in real-time. In the system, a piece of virtual paper is defined in a three dimensional (3D) virtual space and displayed on a graphic screen. An operator can fold it freely and iteratively into complex figure, observing it from an arbitrary direction and manipulating it as if he is folding a real paper, by picking and moving a vertex of the paper using a mouse device. If the position of the picked vertex is different from operator's intentional position delicately, it is corrected automatically in the ..case of matching the picked vertex to another vertex or matching two edges to each other. This function has the operator fold a virtual paper more rapidly and accurately than folding a real paper. This paper also presents how to represent the state of folded paper such as connectivity and overlap relation between paper faces and how to realize interaction using a mouse device in the system.journal articl