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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 â¼ 2500 at 1 Hz and â¼ 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 â¼ 3 at 40 ∘ 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 MATERIAL: The online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users.
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Because they house large biodiversity collections and are also research centres with sequencing facilities, natural history museums are well placed to develop DNA barcoding best practices. The main difficulty is generally the vouchering system: it must ensure that all data produced remain attached to the corresponding specimen, from the field to publication in articles and online databases. The Museum National d'Histoire Naturelle in Paris is one of the leading laboratories in the Marine Barcode of Life (MarBOL) project, which was used as a pilot programme to include barcode collections for marine molluscs and crustaceans. The system is based on two relational databases. The first one classically records the data (locality and identification) attached to the specimens. In the second one, tissue-clippings, DNA extractions (both preserved in 2D barcode tubes) and PCR data (including primers) are linked to the corresponding specimen. All the steps of the process [sampling event, specimen identification, molecular processing, data submission to Barcode Of Life Database (BOLD) and GenBank] are thus linked together. Furthermore, we have developed several web-based tools to automatically upload data into the system, control the quality of the sequences produced and facilitate the submission to online databases. This work is the result of a joint effort from several teams in the Museum National d'Histoire Naturelle (MNHN), but also from a collaborative network of taxonomists and molecular systematists outside the museum, resulting in the vouchering so far of â¼41,000 sequences and the production of â¼11,000 COI sequences.
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Crustáceos/classificação , Crustáceos/genética , Código de Barras de DNA Taxonômico/métodos , Moluscos/classificação , Moluscos/genética , Museus , Animais , Biologia Computacional/métodos , DNA/genética , DNA/isolamento & purificação , ParisRESUMO
Recent morphological and molecular results on phylogeny of euthyneuran gastropods, which include opisthobranchs and pulmonates, have greatly diminished previous supposed resolution of their phylogenetic relationships. In addition to recent morphological results, sequences of the D1 and D2 domains of the 28S rRNA are here analyzed by parsimony for 31 euthyneuran species. The molecular and previous morphological data sets were not congruent according to an ILD test, and morphological and molecular data could not be analyzed simultaneously. Consequently Bremer's Combinable Component Consensus was used to obtain a new tree, with the following supported molecular results: monophyly of a new clade of opisthobranchs including actively swimming Euthyneura, i.e., pelagic Gymnosomata and Thecosomata plus benthic Anaspidea; first molecular confirmation of monophylies of Hygrophila, including Chilina, Acteonoidea, and Sacoglossa, which include both shell-bearing species and slugs; and new confirmation of the monophyly of Stylommatophora. Morphological characters which support the new clades obtained here are discussed.
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Moluscos/genética , Filogenia , RNA Ribossômico 28S/genética , Animais , Sequência de Bases , DNA/química , DNA/genética , Evolução Molecular , Dados de Sequência Molecular , Moluscos/classificação , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido NucleicoRESUMO
Phylogenetic relationships among Phlebotominae were inferred through a pilot study using parsimony analysis of the D2 domain of ribosomal DNA sequences: 455 pairs of bases were sequenced in nine species of Phlebotomine sandflies which belong to the genera Lutzomyia, Phlebotomus and Sergentomyia. Two taxa are used as outgroups: Psychoda sp. and Nemapalpus flavus which is the sister group of the Phlebotominae. The South American genus Lutzomyia appears to be monophyletic. The Mediterranean species Sergentomyia dentata is its sister group and is not clustered with the Old World genus Phlebotomus. The latter is a paraphyletic genus with an early individualization of the branch including the closely related subgenera Phlebotomus and Paraphlebotomus, and a late individualization of the subgenus Larroussius. These results have some consequences on the biogeography of the leishmaniasis in the Old World.
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Evolução Molecular , Phlebotomus/genética , Filogenia , Psychodidae/genética , Animais , Sequência de Bases , DNA Ribossômico/genética , Dados de Sequência Molecular , Projetos Piloto , Homologia de Sequência do Ácido NucleicoRESUMO
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To analyse independently homoplasy for the six possible types of substitution (i.e., A-G, C-T, A-C, A-T, C-G and G-T) at each of the three codon-positions of the cytochrome b gene, two approaches were used: the first is based on the consistency index which measures the amount of homoplasy, and the second is based on the saturation analysis which describes graphically the distribution of homoplasy within the taxonomic sampling. The results obtained from a data set of 32 sequences of Artiodactyla indicate that evolution of the cytochrome b is governed by differential constraints: 1) between the six substitutions-types, 2) between the three codon-positions, and 3) between the two mtDNA strands. Moreover, we find that non-synonymous sites can be more homoplastic than synonymous sites when the possibilities of substitutions are severely restricted because of the functional requirements of hydrophobicity. Most weighting schemes applied to protein-coding genes are elaborated from unjustified assumptions. We propose to weight each substitution-type at each codon-position according to its homoplasy content evaluated either with the consistency index or with an index representing the level of mutational saturation.
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Artiodáctilos/genética , Grupo dos Citocromos b/genética , Evolução Molecular , Filogenia , Sequência de Aminoácidos , Animais , Sequência de Bases , Códon , DNA Mitocondrial/genética , Dados de Sequência MolecularRESUMO
In sponges, as in other taxa with simple organization, the evaluation and use of morphological characters is difficult. Phylogenetic analysis of the first 850 nucleotides from the 5' end of the 28S rRNA gene is used here to assess the homology of spicules used in the classification of the subclass Tetractinellida. A single well-supported MP tree was obtained. The monophyly of the nine Tetractinellida species studied confirms the tetraxon megasclere as a morphological synapomorphy for the Tetractinellida. Two species are reallocated, Penares helleri as a Geodiidae, now thought to have lost sterraster microscleres, and Stryphnus mucronatus to the Streptosclerophorida. SEM micrographs of Stryphnus microscleres show that the morphology of the sanidasters is compatible with the hypothesis that they are homologous with streptoscleres and confirm this reallocation. Two other synapomorphies are confirmed within the tetractinellid clade, the simultaneous presence of tetraxon megasclere and aster-type microsclere (Astrophorida) and the loss of the streptosclere and persistence of the euaster s.s. microscleres (Euastrophorida) evidenced by the reallocation of Stryphnus mucronatus. The streptosclere microscleres cannot be evaluated in terms of homology because Streptosclerophorida may be paraphyletic (although these nodes are not supported by reliable bootstrap proportions) contrary to the currently accepted classification.
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Filogenia , Poríferos/classificação , Animais , Sequência de Bases , DNA/genética , Primers do DNA , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Poríferos/genética , Poríferos/ultraestrutura , RNA Ribossômico 28S/genética , Homologia de Sequência do Ácido NucleicoRESUMO
We have cloned the mitochondrial DNA fragment extending from tRNA-Leu to the cytochrome oxidase subunit 1 (COI) genes of Branchiostoma lanceolatum, Myxine glutinosa, Lampetra fluviatilis, and Scyliorhinus caniculus and have determined their respective gene sequences and organization. In all four species, this region contains the ND1 and ND2 genes and the genes coding eight tRNAs, namely, tRNA-Ile, -Gln, -Met, -Trp, -Ala, -Asn, -Cys, and -Tyr. The gene order is the same in the hagfish, lamprey and dogfish. In the lancelet, the location of the tRNA genes is slightly different. The mitochondrial code of Myxine, Lampetra, and Scyliorhinus is identical to that of vertebrates. The code used by the lancelet is the same with the exception of AGA (a stop codon in vertebrates), which codes for glycine in the lancelet. From the comparison of the four maps with already published ones for other species, we propose that the main features of the craniate mtDNA between the ND1 and COI genes were established in the common ancestor to cephalochordates and vertebrates more than 400 MYA. The origin of replication of the light-strand (Ori-L), usually located between the tRNA-Asn and tRNA-Cys genes in vertebrates, was not found in the lancelet, hagfish, or lamprey (Lampetra). In contrast, it was found in the dogfish. Thus the position of Ori-L was established for the first time in the common ancestor to the Chondrichthyes and Osteichthyes and remained present in all later-emerging vertebrates.