1,564 research outputs found

    K-orbit closures on G/B as universal degeneracy loci for flagged vector bundles with symmetric or skew-symmetric bilinear form

    Full text link
    We use equivariant localization and divided difference operators to determine formulas for the torus-equivariant fundamental cohomology classes of KK-orbit closures on the flag variety G/BG/B, where G = GL(n,\C), and where KK is one of the symmetric subgroups O(n,\C) or Sp(n,\C). We realize these orbit closures as universal degeneracy loci for a vector bundle over a variety equipped with a single flag of subbundles and a nondegenerate symmetric or skew-symmetric bilinear form taking values in the trivial bundle. We describe how our equivariant formulas can be interpreted as giving formulas for the classes of such loci in terms of the Chern classes of the various bundles.Comment: Minor revisions and corrections suggested by referees. Final version, to appear in Transformation Group

    Time-Varying Potassium in High-Resolution Spectra of the Type Ia Supernova 2014J

    Get PDF
    We present a time series of the highest resolution spectra yet published for the nearby Type Ia supernova (SN) 2014J in M82. They were obtained at 11 epochs over 33 days around peak brightness with the Levy Spectrograph (resolution R~110,000) on the 2.4m Automated Planet Finder telescope at Lick Observatory. We identify multiple Na I D and K I absorption features, as well as absorption by Ca I H & K and several of the more common diffuse interstellar bands (DIBs). We see no evolution in any component of Na I D, Ca I, or in the DIBs, but do establish the dissipation/weakening of the two most blueshifted components of K I. We present several potential physical explanations, finding the most plausible to be photoionization of circumstellar material, and discuss the implications of our results with respect to the progenitor scenario of SN 2014J.Comment: 11 pages, 8 figures, 3 tables, submitted to Ap

    Nest ecology of a threatened woodland avifauna

    Get PDF

    A Detailed Report on the Birds Collected on the Chevert Expedition to New Guinea, in 1875

    Get PDF
    The birds collected on the Chevert Expedition in 1875 are reported and discussed on the basis of information published in the two seminal papers of George Masters, Edward Pierson Ramsay and unreported specimens found in the Macleay Museum. In addition, the private journals of Lawrence Hargrave and William Macleay, old newspaper articles and the literature emanating from the expedition were searched. The Chevert Expedition collected: at sea, on islands off the Queensland coast, on Torres Strait islands and New Guinea. A total of 877 individual birds, of 193 species are listed and discussed. This total number includes 84 specimens not previously reported plus 6 sight records of species that were not collected. The history of the imprudent and perfidious management of specimens held by the Macleay Museum, at The University of Sydney, is also reported. In particular, an account of the 36 type specimens, representing 10 species, is given. Most of the surviving types are currently held at The Australian Museum on permanent loan, 12 have been lost and misplaced with 4 of them found in this study. The birds obtained by the expedition from Kendall Broadbent, who was not an expedition member, are presented and discussed. A gazetteer is appended with place names, co-ordinates and the names of the Indigenous language groups where collecting took place. Indigenous communities generously assisted with the collection of birds on their lands

    Discovery and Follow-up Observations of the Young Type Ia Supernova 2016coj

    Get PDF
    The Type~Ia supernova (SN~Ia) 2016coj in NGC 4125 (redshift z=0.004523z=0.004523) was discovered by the Lick Observatory Supernova Search 4.9 days after the fitted first-light time (FFLT; 11.1 days before BB-band maximum). Our first detection (pre-discovery) is merely 0.6±0.50.6\pm0.5 day after the FFLT, making SN 2016coj one of the earliest known detections of a SN Ia. A spectrum was taken only 3.7 hr after discovery (5.0 days after the FFLT) and classified as a normal SN Ia. We performed high-quality photometry, low- and high-resolution spectroscopy, and spectropolarimetry, finding that SN 2016coj is a spectroscopically normal SN Ia, but with a high velocity of \ion{Si}{2} λ\lambda6355 (12,600\sim 12,600\,\kms\ around peak brightness). The \ion{Si}{2} λ\lambda6355 velocity evolution can be well fit by a broken-power-law function for up to a month after the FFLT. SN 2016coj has a normal peak luminosity (MB18.9±0.2M_B \approx -18.9 \pm 0.2 mag), and it reaches a BB-band maximum \about16.0~d after the FFLT. We estimate there to be low host-galaxy extinction based on the absence of Na~I~D absorption lines in our low- and high-resolution spectra. The spectropolarimetric data exhibit weak polarization in the continuum, but the \ion{Si}{2} line polarization is quite strong (0.9%±0.1%\sim 0.9\% \pm 0.1\%) at peak brightness.Comment: Submitte

    Modeling the uptake of plug-in vehicles in a heterogeneous car market using a consumer segmentation approach

    Get PDF
    There is broad agreement on the need for substantial use of low carbon vectors in the long term in the transport sector. Electrification, via mass market adoption of plug-in vehicles (i.e. battery electric and plug-in hybrid electric vehicles), has emerged as a front runner for road transport across the globe, but there are concerns that the pace and extent implied by many modelling studies is problematic and that assessment of (a) the heterogeneity in the market, (b) other low carbon vectors (e.g. conventional hybrids, hydrogen fuel cell) and (c) life cycle energy and environmental impacts have been relatively neglected. This paper aims to fill these gaps by examining the timing, scale and impacts of the uptake of plug-in vehicles in the heterogeneous UK car market from a consumer perspective. To achieve this aim it (a) brings together a bespoke disaggregated model of the transport-energy-environment system (the UK Transport Carbon Model) with previous work by the authors on heterogeneity in the demand for and supply of plug-in vehicles and (b) applies the improved model to develop future low carbon scenarios that assess the potential impact of different investment pathways and policy approaches to the electrification of cars with the view to meeting the UK’s legally binding carbon budgets to 2050. The results show the importance of accounting for the heterogeneity in and dynamic nature of the car market in terms of new technology adoption by private consumers, so called ‘user choosers’ and fleet managers, as well as accounting for potential effects on wider life cycle emissions resulting from different uptake pathways. It allows an assessment of the effectiveness of different policy instruments, market conditions (vehicle supply, private vs fleet market, vehicle segments) and social factors (consumer awareness, range “anxiety”, perceived charging requirements) on different consumer segments, thus providing more policy-focused conclusions on the likely pathways to high penetration of plug-in vehicles that may be required to meet future carbon and air quality targets

    A scoping review of observational studies examining relationships between environmental behaviors and health behaviors

    Get PDF
    Individual lifestyles are key drivers of both environmental change and chronic disease. We undertook a scoping review of peer-reviewed studies which examined associations between environmental and health behaviors of individuals in high-income countries. We searched EconLit, Medline, BIOSIS and the Social Science Citation Index. A total of 136 studies were included. The majority were USA-based cross-sectional studies using self-reported measures. Most of the evidence related to travel behavior, particularly active travel (walking and cycling) and physical activity (92 studies) or sedentary behaviors (19 studies). Associations of public transport use with physical activity were examined in 18 studies, and with sedentary behavior in one study. Four studies examined associations between car use and physical activity. A small number included other environmental behaviors (food-related behaviors (n = 14), including organic food, locally-sourced food and plate waste) and other health behaviors ((n = 20) smoking, dietary intake, alcohol). These results suggest that research on individual environmental and health behaviors consists largely of studies examining associations between travel mode and levels of physical activity. There appears to be less research on associations between other behaviors with environmental and health impacts, and very few longitudinal studies in any domain

    Writing in Britain and Ireland, c. 400 to c. 800

    Get PDF
    No abstract available

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

    Get PDF
    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts
    corecore