15 research outputs found

    Applicability of an Hertzian-type contact model for wheel-rail pairings as seen by an improved post-processing scheme for ultrasonic data

    Full text link
    The contact between wheel and rail crucially affects the management of railways, since the vehicle dynamics, safety, and performance, for example, are all dependent on this. Therefore, in this contribution the loaddependence of nominal contact area - a broadly not considered aspect of the wheel-rail contacts within the literature - is addressed. We are applying an ultrasonic technique for the detection of the contact zone and an improved post-processing scheme for the measured ultrasonic reflection data. Accordingly, we found that the nominal contact area shows a power-law dependence on load which only on average is predicted by the elliptical Hertzian contact theory

    Electronic structure and bonding in skutterudite-type phosphides

    Full text link
    The electronic structures of the skutterudite-type phosphides CoP3 and NiP3 have been investigated by means of first-principles linear muffin-tin orbital–atomic sphere approximation band-structure calculations. The presence of P4 rings in the skutterudite structure is of great importance in determining the nature of the electronic bands around the Fermi level, composed mainly of p-type molecular orbitals of these units. The metallic character found for NiP3 should be ascribed to the phosphorus framework rather than to the metal atoms

    Electronic structure and bonding in skutterudite-type phosphides

    Full text link
    The electronic structures of the skutterudite-type phosphides CoP3 and NiP3 have been investigated by means of first-principles linear muffin-tin orbital–atomic sphere approximation band-structure calculations. The presence of P4 rings in the skutterudite structure is of great importance in determining the nature of the electronic bands around the Fermi level, composed mainly of p-type molecular orbitals of these units. The metallic character found for NiP3 should be ascribed to the phosphorus framework rather than to the metal atoms

    A Modular Approach to Vocal Learning:Disentangling the Diversity of a Complex Behavioral Trait

    Full text link
    Vocal learning is a behavioral trait in which the social and acoustic environment shapes the vocal repertoire of individuals. Over the past century, the study of vocal learning has progressed at the intersection of ecology, physiology, neuroscience, molecular biology, genomics, and evolution. Yet, despite the complexity of this trait, vocal learning is frequently described as a binary trait, with species being classified as either vocal learners or vocal non-learners. As a result, studies have largely focused on a handful of species for which strong evidence for vocal learning exists. Recent studies, however, suggest a continuum in vocal learning capacity across taxa. Here, we further suggest that vocal learning is a multi-component behavioral phenotype comprised of distinct yet interconnected modules. Discretizing the vocal learning phenotype into its constituent modules would facilitate integration of findings across a wider diversity of species, taking advantage of the ways in which each excels in a particular module, or in a specific combination of features. Such comparative studies can improve understanding of the mechanisms and evolutionary origins of vocal learning. We propose an initial set of vocal learning modules supported by behavioral and neurobiological data and highlight the need for diversifying the field in order to disentangle the complexity of the vocal learning phenotype.</p

    Electronic structure and bonding in skutterudite-type phosphides

    Get PDF
    The electronic structures of the skutterudite-type phosphides CoP3 and NiP3 have been investigated by means of first-principles linear muffin-tin orbital–atomic sphere approximation band-structure calculations. The presence of P4 rings in the skutterudite structure is of great importance in determining the nature of the electronic bands around the Fermi level, composed mainly of p-type molecular orbitals of these units. The metallic character found for NiP3 should be ascribed to the phosphorus framework rather than to the metal atoms

    Towards complete and error-free genome assemblies of all vertebrate species

    Full text link
    High-quality and complete reference genome assemblies are fundamental for the application of genomics to biology, disease, and biodiversity conservation. However, such assemblies are available for only a few non-microbial species1,2,3,4. To address this issue, the international Genome 10K (G10K) consortium5,6 has worked over a five-year period to evaluate and develop cost-effective methods for assembling highly accurate and nearly complete reference genomes. Here we present lessons learned from generating assemblies for 16 species that represent six major vertebrate lineages. We confirm that long-read sequencing technologies are essential for maximizing genome quality, and that unresolved complex repeats and haplotype heterozygosity are major sources of assembly error when not handled correctly. Our assemblies correct substantial errors, add missing sequence in some of the best historical reference genomes, and reveal biological discoveries. These include the identification of many false gene duplications, increases in gene sizes, chromosome rearrangements that are specific to lineages, a repeated independent chromosome breakpoint in bat genomes, and a canonical GC-rich pattern in protein-coding genes and their regulatory regions. Adopting these lessons, we have embarked on the Vertebrate Genomes Project (VGP), an international effort to generate high-quality, complete reference genomes for all of the roughly 70,000 extant vertebrate species and to help to enable a new era of discovery across the life sciences

    Towards complete and error-free genome assemblies of all vertebrate species.

    Get PDF
    High-quality and complete reference genome assemblies are fundamental for the application of genomics to biology, disease, and biodiversity conservation. However, such assemblies are available for only a few non-microbial species1-4. To address this issue, the international Genome 10K (G10K) consortium5,6 has worked over a five-year period to evaluate and develop cost-effective methods for assembling highly accurate and nearly complete reference genomes. Here we present lessons learned from generating assemblies for 16 species that represent six major vertebrate lineages. We confirm that long-read sequencing technologies are essential for maximizing genome quality, and that unresolved complex repeats and haplotype heterozygosity are major sources of assembly error when not handled correctly. Our assemblies correct substantial errors, add missing sequence in some of the best historical reference genomes, and reveal biological discoveries. These include the identification of many false gene duplications, increases in gene sizes, chromosome rearrangements that are specific to lineages, a repeated independent chromosome breakpoint in bat genomes, and a canonical GC-rich pattern in protein-coding genes and their regulatory regions. Adopting these lessons, we have embarked on the Vertebrate Genomes Project (VGP), an international effort to generate high-quality, complete reference genomes for all of the roughly 70,000 extant vertebrate species and to help to enable a new era of discovery across the life sciences
    corecore