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Consideration of the three-dimensional heterogeneity of mantle rheology allows models of viscoelastic relaxation following the 2004 Sumatra-Andaman earthquake to simultaneously fit both the observed far-field and near-field postseismic deformation. We use horizontal and vertical campaign and continuous GPS observations from the Andaman, Nicobar, and Sumatran forearc islands, mainland Sumatra, Thailand, the Malay Peninsula, the Indian Ocean, and southern India, spanning the first five years of postseismic deformation. The postseismic relaxation models consider contributions from the 2004 Mw 9.2 Sumatra-Andaman, the 2005 Mw 8.7 Nias, and 2007 Mw 8.4 Bengkulu earthquakes. Far-field motions to the east of the ruptures are equally well fit by homogeneous or laterally variable earth models. However, only models with contrasting rheology across the subducting slab, a ten-times higher mantle viscosity under the Indian Ocean lithosphere than the backarc mantle, can also produce the observed enduring postseismic uplift along the forearc and lack of far-field transient displacements in southern India. While postseismic uplift of forearc stations can also be produced by rapid and enduring down-dip afterslip, the inferred rheology structure is consistent with the distribution of mantle temperature inferred from seismic tomography.

SUMMARY We investigate the source of the Mw 7.6 Padang earthquake by inverting three-component global positioning system (GPS) data and broad-band regional seismic-displacement waveforms. The earthquake involved oblique-reverse slip either on an E-W, south-dipping plane, or on a N-S, west-dipping plane. Finite-fault inversions indicate that the rupture primarily propagated downdip and southwest from the hypocentre, with a scalar seismic moment between 3.4 and 3.7 × 1020 N m ( Mw 7.62-7.65). Analysis of the seismic and geodetic data do not allow for unique identification of the causative focal plane. Aftershock patterns strongly suggest the E-W plane was the causative focal plane, but aligned geological structures in the downgoing plate favour the N-S plane. In either case, this unusually large intraslab earthquake has moved closer to failure the deepest portion of the overlying megathrust, which last ruptured during a great earthquake more than two centuries ago and is late in its seismic cycle. [ABSTRACT FROM AUTHOR]

The Bengkulu MW 8.4 earthquake on 12 September 2007, close in time and space to the 2004 MW 9.2 Sumatra-Andaman and 2005 MW 8.7 Nias megathrust events, suggests that it could be a triggered earthquake. It was located in the southern portion of the historic 1833 MW 8.9 rupture. However, it appears perplexing that the portion of the Sunda subduction zone between the Nias and Bengkulu rupture patches, which last ruptured in a 1797 MW 8.7 event, did not recur first. Coulomb failure stress (CFF) modeling of the 2004 and 2005 megathrust earthquakes and subsequent post-seismic relaxation processes fails to explain why the 2007 patch ruptured before the northern 1797 segment. Surprisingly, the much smaller 2000 MW 8.0 Enggano earthquake produced a much larger positive CFF change at the 2007 hypocenter and may help to explain the southern location of the 2007 earthquake. Investigation of changes in seismicity rates in the region following the 2004-2005 events shows that the megathrust earthquakes may have dynamically triggered slip near the northern end of the 2007 rupture zone. A large increase in seismicity levels following the 2000 earthquake may also have influenced the eventual initiation point of the 2007 earthquake. Regrettably, the section of the Sunda megathrust near Siberut that last ruptured in 1797 still poses a great seismic hazard to the region as the only segment not to have ruptured in the sequence of twenty-first century megathrust earthquakes. [ABSTRACT FROM AUTHOR]

The Genome in a Bottle Consortium (GIAB), hosted by the National Institute of Standards and Technology (NIST), is developing new matched tumor-normal samples, the first to be explicitly consented for public dissemination of genomic data and cell lines. Here, we describe a comprehensive genomic dataset from the first individual, HG008, including DNA from an adherent, epithelial-like pancreatic ductal adenocarcinoma (PDAC) tumor cell line and matched normal cells from duodenal and pancreatic tissues. Data for the tumor-normal matched samples comes from thirteen distinct state-of-the-art whole genome measurement technologies, including high depth short and long-read bulk whole genome sequencing (WGS), single cell WGS, and Hi-C, and karyotyping. These data will be used by the GIAB Consortium to develop matched tumor-normal benchmarks for somatic variant detection. We expect these data to facilitate innovation for whole genome measurement technologies, de novo assembly of tumor and normal genomes, and bioinformatic tools to identify small and structural somatic mutations. This first-of-its-kind broadly consented open-access resource will facilitate further understanding of sequencing methods used for cancer biology., Competing Interests: Competing interests A.S. and K.S. are employees of Arima Genomics. L.F.P. from BCM, was sponsored by Genentech Inc until September 2023. F.J.S from BCM, received research support from Illumina, ONT and Pacbio. A.R.H and H-C.Y. are employees of Bionano Genomics and own stock shares and options of Bionano Genomics, Inc. V.W., K.K., J.R., and I.G. are employees of BioSkryb Genomics. M.S., K.B., B.R.L. and S.L. are employees of Element Biosciences. S.B.K., C.L., P.B., A.M.W., I.J.M., A.A., C.K., M.W., and Y.K. are employees and shareholders of PacBio, Inc. D.L., H.B., N.I., and I.S. are employees and shareholders of Ultima Genomics. S.E. and M.W. are employees of Phase Genomics. E.C., G.H., S.G., and M.V. are employees of KromaTiD, Inc, E.C. is also a shareholder. F.B., E.S., K.S., S.T. and S.C. are employees of Illumina, Inc. All other authors have no competing interests.

Background: DNA sequencing is a critical tool in modern biology. Over the last two decades, it has been revolutionized by the advent of massively parallel sequencing, leading to significant advances in the genome and transcriptome sequencing of various organisms. Nevertheless, challenges with accuracy, lack of competitive options and prohibitive costs associated with high throughput parallel short-read sequencing persist., Results: Here, we conduct a comparative analysis using matched DNA and RNA short-reads assays between Element Biosciences' AVITI and Illumina's NextSeq 550 chemistries. Similar comparisons were evaluated for synthetic long-read sequencing for RNA and targeted single-cell transcripts between the AVITI and Illumina's NovaSeq 6000. For both DNA and RNA short-read applications, the study found that the AVITI produced significantly higher per sequence quality scores. For PCR-free DNA libraries, we observed an average 89.7% lower experimentally determined error rate when using the AVITI chemistry, compared to the NextSeq 550. For short-read RNA quantification, AVITI platform had an average of 32.5% lower error rate than that for NextSeq 550. With regards to synthetic long-read mRNA and targeted synthetic long read single cell mRNA sequencing, both platforms' respective chemistries performed comparably in quantification of genes and isoforms. The AVITI displayed a marginally lower error rate for long reads, with fewer chemistry-specific errors and a higher mutation detection rate., Conclusion: These results point to the potential of the AVITI platform as a competitive candidate in high-throughput short read sequencing analyses when juxtaposed with the Illumina NextSeq 550., Competing Interests: Conflict of interest: SL, YPY, BGR, JJL, WW, and JHL declare no conflict of interest, while CO, JZ, KB, BJK, KW, MS, and TBY are employees of Element Biosciences, Inc.