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SEIS: Insight's Seismic Experiment for Internal Structure of Mars.
By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ⌠2500 at 1 Hz and ⌠200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ⌠3 at 40 â epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution.Electronic supplementary materialThe online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users
Structural, magnetic and electrical properties of the lithium ferrite obtained by ball milling and heat treatment
Maternal Wnt/ÎČ-Catenin Signaling Coactivates Transcription through NF-ÎșB Binding Sites during Xenopus Axis Formation
Maternal Wnt/ÎČ-Catenin signaling establishes a program of dorsal-specific gene expression required for axial patterning in Xenopus. We previously reported that a subset of dorsally expressed genes depends not only on Wnt/ÎČ-Catenin stimulation, but also on a MyD88-dependent Toll-like receptor/IL1-receptor (TLR/IL1-R) signaling pathway. Here we show that these two signal transduction cascades converge in the nucleus to coactivate gene transcription in blastulae through a direct interaction between ÎČ-Catenin and NF-ÎșB proteins. A transdominant inhibitor of NF-ÎșB, ÎNIÎșBα, phenocopies loss of MyD88 protein function, implicating Rel/NF-ÎșB proteins as selective activators of dorsal-specific gene expression. Sensitive axis formation assays in the embryo demonstrate that dorsalization by Wnt/ÎČ-Catenin requires NF-ÎșB protein activity, and vice versa. Xenopus nodal-related 3 (Xnr3) is one of the genes with dual ÎČ-Catenin/NF-ÎșB input, and a proximal NF-ÎșB consensus site contributes to the regional activity of its promoter. We demonstrate in vitro binding of Xenopus ÎČ-Catenin to several XRel proteins. This interaction is observed in vivo upon Wnt-stimulation. Finally, we show that a synthetic luciferase reporter gene responds to both endogenous and exogenous ÎČ-Catenin levels in an NF-ÎșB motif dependent manner. These results suggest that ÎČ-Catenin acts as a transcriptional co-activator of NF-ÎșB-dependent transcription in frog primary embryonic cells
Mapping circulating serum miRNAs to their immune-related target mRNAs
Bakhtiyor Nosirov,1 Joël Billaud,1 Alexis Vandenbon,2 Diego Diez,3 Edward Wijaya,1 Ken J Ishii,4,5 Shunsuke Teraguchi,3 Daron M Standley1,6 1Systems Immunology Lab, 2Immuno-Genomics Research Unit, 3Quantitative Immunology Research Unit, 4Laboratory of Vaccine Science, WPI Immunology Frontier Research Center, Osaka University, Suita, 5Laboratory of Adjuvant Innovation, National Institute of Biomedical Innovation, Osaka, 6Lab of Integrated Biological Information, Institute for Virus Research Kyoto University, Kyoto, Japan Purpose: Evidence suggests that circulating serum microRNAs (miRNAs) might preferentially target immune-related mRNAs. If this were the case, we hypothesized that immune-related mRNAs would have more predicted serum miRNA binding sites than other mRNAs and, reciprocally, that serum miRNAs would have more immune-related mRNA targets than non-serum miRNAs.Materials and methods: We developed a consensus target predictor using the random forest framework and calculated the number of predicted miRNA–mRNA interactions in various subsets of miRNAs (serum, non-serum) and mRNAs (immune related, nonimmune related).Results: Immune-related mRNAs were predicted to be targeted by serum miRNA more than other mRNAs. Moreover, serum miRNAs were predicted to target many more immune-related mRNA targets than non-serum miRNAs; however, these two biases in immune-related mRNAs and serum miRNAs appear to be completely independent.Conclusion: Immune-related mRNAs have more miRNA binding sites in general, not just for serum miRNAs; likewise, serum miRNAs target many more mRNAs than non-serum miRNAs overall, regardless of whether they are immune related or not. Nevertheless, these two independent phenomena result in a significantly larger number of predicted serum miRNA–immune mRNA interactions than would be expected by chance. Keywords: biomarker, posttranscriptional regulation, random forest, target predictio
Interspecific variation across angiosperms in global DNA methylation: phylogeny, ecology and plant features in tropical and Mediterranean communities
The interspecific range of epigenetic variation and the degree to which differences between angiosperm species are related to geography, evolutionary history, ecological settings or species-specific traits, remain essentially unexplored. Genome-wide global DNA cytosine methylation is a tractable âepiphenotypicâ feature suitable for exploring these relationships. Global cytosine methylation was estimated in 279 species from two distant, ecologically disparate geographical regions: Mediterranean Spain and tropical MĂ©xico. At each region, four distinct plant communities were analyzed. Global methylation spanned a 10-fold range among species (4.8â42.2%). Interspecific differences were related to evolutionary trajectories, as denoted by a strong phylogenetic signal. Genomes of tropical species were on average less methylated than those of Mediterranean ones. Woody plants have genomes with lower methylation than perennial herbs, and genomes of widespread species were less methylated than those of species with restricted geographical distribution. The eight communities studied exhibited broad and overlapping interspecific variances in global cytosine methylation and only two of them differed in average methylation. Altogether, our broad taxonomic survey supported global methylation as a plant âepiphenotypicâ trait largely associated with species evolutionary history, genome size, range size and woodiness. Additional studies are required for better understanding the environmental components underlying local and geographical variation.Peer Reviewe