Destruction of Interstellar Dust in Evolving Supernova Remnant Shock Waves

Supernova generated shock waves are responsible for most of the destruction of dust grains in the interstellar medium (ISM). Calculations of the dust destruction timescale have so far been carried out using plane parallel steady shocks, however that approximation breaks down when the destruction timescale becomes longer than that for the evolution of the supernova remnant (SNR) shock. In this paper we present new calculations of grain destruction in evolving, radiative SNRs. To facilitate comparison with the previous study by Jones et al. (1996), we adopt the same dust properties as in that paper. We find that the efficiencies of grain destruction are most divergent from those for a steady shock when the thermal history of a shocked gas parcel in the SNR differs significantly from that behind a steady shock. This occurs in shocks with velocities >~ 200 km/s for which the remnant is just beginning to go radiative. Assuming SNRs evolve in a warm phase dominated ISM, we find dust destruction timescales are increased by a factor of ~2 compared to those of Jones et al. (1996), who assumed a hot gas dominated ISM. Recent estimates of supernova rates and ISM mass lead to another factor of ~3 increase in the destruction timescales, resulting in a silicate grain destruction timescale of ~2-3 Gyr. These increases, while not able resolve the problem of the discrepant timescales for silicate grain destruction and creation, are an important step towards understanding the origin, and evolution of dust in the ISM.Comment: 30 pages, 8 figures, accepted for publication in the Astrophysical Journa

Cool Jupiters greatly outnumber their toasty siblings : Occurrence rates from the Anglo-Australian Planet Search

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©2019 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Our understanding of planetary systems different to our own has grown dramatically in the past 30 yr. However, our efforts to ascertain the degree to which the Solar system is abnormal or unique have been hindered by the observational biases inherent to the methods that have yielded the greatest exoplanet hauls. On the basis of such surveys, one might consider our planetary system highly unusual - but the reality is that we are only now beginning to uncover the true picture. In this work, we use the full 18-yr archive of data from the Anglo-Australian Planet Search to examine the abundance of 'cool Jupiters' - analogues to the Solar system's giant planets, Jupiter and Saturn. We find that such planets are intrinsically far more common through the cosmos than their siblings, the hot Jupiters.We find that the occurrence rate of such 'cool Jupiters' is 6.73 +2.09 -1.13 per cent, almost an order of magnitude higher than the occurrence of hot Jupiters (at 0.84 +0.70 -0.20 per cent). We also find that the occurrence rate of giant planets is essentially constant beyond orbital distances of ~1 au. Our results reinforce the importance of legacy radial velocity surveys for the understanding of the Solar system's place in the cosmos.Peer reviewe

Reduced swimming performance repeatedly evolves on loss of migration in landlocked populations of alewife

Author Posting. © University of Chicago, 2018. This article is posted here by permission of University of Chicago Press for personal use, not for redistribution. The definitive version was published in Physiological and Biochemical Zoology 91 (2018):814–825, doi:10.1086/696877.Whole-organism performance tasks are accomplished by the integration of morphological traits and physiological functions. Understanding how evolutionary change in morphology and physiology influences whole-organism performance will yield insight into the factors that shape its own evolution. We demonstrate that nonmigratory populations of alewife (Alosa pseudoharengus) have evolved reduced swimming performance in parallel, compared with their migratory ancestor. In contrast to theoretically and empirically based predictions, poor swimming among nonmigratory populations is unrelated to the evolution of osmoregulation and occurs despite the fact that nonmigratory alewives have a more fusiform (torpedo-like) body shape than their ancestor. Our results suggest that elimination of long-distance migration from the life cycle has shaped performance more than changes in body shape and physiological regulatory capacity.Funding was provided by the University of Connecticut’s Department of Ecology and Evolutionary Biology and El Muy Viejo.2019-01-3

Reduced swimming performance repeatedly evolves on loss of migration in landlocked populations of alewife

Author Posting. © University of Chicago, 2018. This article is posted here by permission of University of Chicago Press for personal use, not for redistribution. The definitive version was published in Physiological and Biochemical Zoology 91 (2018):814–825, doi:10.1086/696877.Whole-organism performance tasks are accomplished by the integration of morphological traits and physiological functions. Understanding how evolutionary change in morphology and physiology influences whole-organism performance will yield insight into the factors that shape its own evolution. We demonstrate that nonmigratory populations of alewife (Alosa pseudoharengus) have evolved reduced swimming performance in parallel, compared with their migratory ancestor. In contrast to theoretically and empirically based predictions, poor swimming among nonmigratory populations is unrelated to the evolution of osmoregulation and occurs despite the fact that nonmigratory alewives have a more fusiform (torpedo-like) body shape than their ancestor. Our results suggest that elimination of long-distance migration from the life cycle has shaped performance more than changes in body shape and physiological regulatory capacity.Funding was provided by the University of Connecticut’s Department of Ecology and Evolutionary Biology and El Muy Viejo.2019-01-3

Spatial patterns in the oxygen isotope composition of daily rainfall in the British Isles

Understanding the modern day relationship between climate and the oxygen isotopic composition of precipitation (δ18OP) is crucial for obtaining rigorous palaeoclimate reconstructions from a variety of archives. To date, the majority of empirical studies into the meteorological controls over δ18OP rely upon daily, event scale, or monthly time series from individual locations, resulting in uncertainties concerning the representativeness of statistical models and the mechanisms behind those relationships. Here, we take an alternative approach by analysing daily patterns in δ18OP from multiple stations across the British Isles (n = 10–70 stations). We use these data to examine the spatial and seasonal heterogeneity of regression statistics between δ18OP and common predictors (temperature, precipitation amount and the North Atlantic Oscillation index; NAO). Temperature and NAO are poor predictors of daily δ18OP in the British Isles, exhibiting weak and/or inconsistent effects both spatially and between seasons. By contrast δ18OP and rainfall amount consistently correlate at most locations, and for all months analysed, with spatial and temporal variability in the regression coefficients. The maps also allow comparison with daily synoptic weather types, and suggest characteristic δ18OP patterns, particularly associated with Cylonic Lamb Weather Types. Mapping daily δ18OP across the British Isles therefore provides a more coherent picture of the patterns in δ18OP, which will ultimately lead to a better understanding of the climatic controls. These observations are another step forward towards developing a more detailed, mechanistic framework for interpreting stable isotopes in rainfall as a palaeoclimate and hydrological tracer

NASA Manned Launch Vehicle Lightning Protection Development

Historically, the National Aeronautics and Space Administration (NASA) relied heavily on lightning avoidance to protect launch vehicles and crew from lightning effects. As NASA transitions from the Space Shuttle to the new Constellation family of launch vehicles and spacecraft, NASA engineers are imposing design and construction standards on the spacecraft and launch vehicles to withstand both the direct and indirect effects of lightning. A review of current Space Shuttle lightning constraints and protection methodology will be presented, as well as a historical review of Space Shuttle lightning requirements and design. The Space Shuttle lightning requirements document, NSTS 07636, Lightning Protection, Test and Analysis Requirements, (originally published as document number JSC 07636, Lightning Protection Criteria Document) was developed in response to the Apollo 12 lightning event and other experiences with NASA and the Department of Defense launch vehicles. This document defined the lightning environment, vehicle protection requirements, and design guidelines for meeting the requirements. The criteria developed in JSC 07636 were a precursor to the Society of Automotive Engineers (SAE) lightning standards. These SAE standards, along with Radio Technical Commission for Aeronautics (RTCA) DO-160, Environmental Conditions and Test Procedures for Airborne Equipment, are the basis for the current Constellation lightning design requirements. The development and derivation of these requirements will be presented. As budget and schedule constraints hampered lightning protection design and verification efforts, the Space Shuttle elements waived the design requirements and relied on lightning avoidance in the form of launch commit criteria (LCC) constraints and a catenary wire system for lightning protection at the launch pads. A better understanding of the lightning environment has highlighted the vulnerability of the protection schemes and associated risk to the vehicle, which has resulted in lost launch opportunities and increased expenditures in manpower to assess Space Shuttle vehicle health and safety after lightning events at the launch pad. Because of high-percentage launch availability and long-term on-pad requirements, LCC constraints are no longer considered feasible. The Constellation vehicles must be designed to withstand direct and indirect effects of lightning. A review of the vehicle design and potential concerns will be presented as well as the new catenary lightning protection system for the launch pad. This system is required to protect the Constellation vehicles during launch processing when vehicle lightning effects protection might be compromised by such items as umbilical connections and open access hatches

Correction to: Solvent free synthesis of PdZn/TiO2 catalysts for the hydrogenation of CO2 to methanol

The article Solvent Free Synthesis of PdZn/TiO2 Catalysts for the Hydrogenation of CO2 to Methanol by Hasliza Bahruji, Jonathan Ruiz Esquius, Michael Bowker, Graham Hutchings, Robert D. Armstrong, Wilm Jones was originally published Online First without open access. After publication in volume 61, issue 3–4, pages 144–153, the author decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to ©The Author(s) 2018 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made

Non-adiabatically detecting the geometric phase of the macroscopic quantum state with symmetric SQUID

We give a simple way to detect the geometric phase shift and the conditional geometric phase shift with Josephson junction system. Comparing with the previous work(Falcl G, Fazio R, Palma G.M., Siewert J and Verdal V, {\it Nature} {\bf 407}, 355(2000)), our scheme has two advantages. We use the non-adiabatic operation, thus the detection is less affected by the decoherence. Also, we take the time evolution on zero dynamic phase loop, we need not take any extra operation to cancel the dynamic phase.Comment: 8 pages, 4 figure