Stress relaxation arrested the mainshock rupture of the 2016 Central Tottori earthquake

地震の破壊はなぜ止まるのか? --2016年鳥取県中部地震の断層サイズを決めたもの--. 京都大学プレスリリース. 2021-08-12.After a large earthquake, many small earthquakes, called aftershocks, ensue. Additional large earthquakes typically do not occur, despite the fact that the large static stress near the edges of the fault is expected to trigger further large earthquakes at these locations. Here we analyse ~10, 000 highly accurate focal mechanism solutions of aftershocks of the 2016 Mw 6.2 Central Tottori earthquake in Japan. We determine the location of the horizontal edges of the mainshock fault relative to the aftershock hypocentres, with an accuracy of approximately 200 m. We find that aftershocks rarely occur near the horizontal edges and extensions of the fault. We propose that the mainshock rupture was arrested within areas characterised by substantial stress relaxation prior to the main earthquake. This stress relaxation along fault edges could explain why mainshocks are rarely followed by further large earthquakes

Copy Number Variations Due to Large Genomic Deletion in X-Linked Chronic Granulomatous Disease

Mutations in genes for any of the six subunits of NADPH oxidase cause chronic granulomatous disease (CGD), but almost 2/3 of CGD cases are caused by mutations in the X-linked CYBB gene, also known as NAD (P) H oxidase 2. Approximately 260 patients with CGD have been reported in Japan, of whom 92 were shown to have mutations of the CYBB gene and 16 to have chromosomal deletions. However, there has been very little detailed analysis of the range of the deletion or close understanding of the disease based on this. We therefore analyzed genomic rearrangements in X-linked CGD using array comparative genomic hybridization analysis, revealing the extent and the types of the deletion genes. The subjects were five Japanese X-linked CGD patients estimated to have large base deletions of 1 kb or more in the CYBB gene (four male patients, one female patient) and the mothers of four of those patients. The five Japanese patients were found to range from a patient exhibiting deletions only of the CYBB gene to a female patient exhibiting an extensive DNA deletion and the DMD and CGD phenotype manifested. Of the other three patients, two exhibited CYBB, XK, and DYNLT3 gene deletions. The remaining patient exhibited both a deletion encompassing DNA subsequent to the CYBB region following intron 2 and the DYNLT3 gene and a complex copy number variation involving the insertion of an inverted duplication of a region from the centromere side of DYNLT3 into the deleted region

A Comparative Analysis of Changes of Student’s Attitude Before and After an International Virtual Learning Class

The purpose of this study was to investigate the effects of international virtual learning classes. For the purpose, the class implemented using multipoint communication system which was constructed high quality video transfer systems on a cross-border infrastructure (gigabit bandwidth) between Japan to South Korea. In order to reveal the effects of the class, a questionnaire was composed of five categories; Consciousness to Foreign Countries, Nationality, Acquisition of View Point, Motivation, Recognition to the partner country. The results of 2x2 mixed two-way ANOVA showed differences of characteristics of two countries and changes of student’s attitude. The results revealed that an international virtual learning class has a possibility to develop and enhance student\u27s awareness of humanity and the world. Future implementation will depend on growth and sustenance of the international relationship for a prolonged period

The Results of aCGH and Direct Sequence Analysis Spanning the Deletion Breakpoints in Patient 2.

<p>A female's DNA was used for the control. According to aCGH, the deletion site was 84.4 kbp and the duplication site 91.9 kb. According to the DNA walking analysis by PCR, a breakpoint was located at 37398670 of <i>CYBB</i> intron 2. Furthermore, six bases of the gene at 37612392 (UCSC hg17 May.2004) of ATACCT were bound inverted at the breakpoint, and complex structural abnormalities showing gene deletions on the inner side and duplication of the inverted part were observed.</p

Genomic Rearrangement Mechanisms.

<p>For the gene deletions in patient 1, gene rearrangements exhibiting deletions due to non-homologous end-joining (NHEJ) were thought to have occurred, since repeated two base sequences of TA were observed at both ends of the gene (1a, 1b). In patient 2, it was hypothesized that rearrangement might have occurred through a mechanism involving a combination of fork stalling and template switching (FoSTeS)/microhomology-mediated break-induced replication (MMBIR). A three base repeat sequence of AAT prone to cause changes in copy number or sequence swaps was observed in a discontinuous end of the lagging strand during DNA replication. This formed a loop by binding to TTA on its complementary strand with replication slippage occurring (2a). At the discontinuous end, the lagging strand with the loop formed had a six base microhomology of AGGTAT and dissociated. The dissociated end subsequently bound to the ATACCT found at the duplication front of the leading strand. Synthesis and extension of the leading strand then occurred originating from the binding site (2b). The gene synthesized on the leading strand is hypothesized to cause structural abnormalities leading to duplications of the DNA strand subsequent to the DNA strand deletion by returning to the lagging strand after the end of duplication and the binding of the end that has finished duplication to the starting end of the normal gene on the lagging strand by DNA ligase (2c).</p

The Results of aCGH Analysis Spanning the Deletion Breakpoints in Patients 3 and 4.

<p>A female's DNA was used for the control DNA for patient 3, and a male's for patient 4. These male infants suffered deletions of three genes: the chronic granulomatous disease gene (<i>CYBB</i>), the McLeod syndrome gene (<i>XK</i>), and <i>DYNLT3</i>. The gene deletions in each patient were found to be 0.59 Mb and 1.94 Mb, respectively.</p

The Results of aCGH Analysis Spanning the Deletion Breakpoints in Mother and Patient 5.

<p>A female's DNA was used for the control DNA. This case involved deletions of four genes, the chronic granulomatous disease gene (<i>CYBB</i>), the Duchenne muscular dystrophy gene (<i>DMD</i>), the McLeod syndrome gene (<i>XK</i>), and <i>DYNLT3</i>. The gene deletion region was about 5.71 Mb and encompassed an area from <i>CYBB</i> to the greater part of the <i>DMD</i> (b). A similar gene deletion was also observed in the mother (a).</p