607 research outputs found
Postcard: Supreme Lodge, Knights of Columbia
This black and white printed postcard depicts a receipt for annual dues to the Knights of Columbia. Printed text and handwriting are on the front of the card. Handwriting is on the back of the card.https://scholars.fhsu.edu/tj_postcards/2171/thumbnail.jp
Optimising the spatial pattern of landscape revegetation
The spatial pattern of landscape reconstruction makes a substantial difference to environmental outcomes. We develop a spatially explicit bio-economic model that optimises the reconstruction of a heavily cleared landscape through revegetation. The model determines the spatial priorities for revegetation that minimises economic costs subject to achieving particular improvements in habitat for 29 woodland-dependent bird species. The study focuses on the Avoca catchment (330 thousand ha) in North-Central Victoria. Our model incorporates spatial pattern and heterogeneity of existing and reconstructed vegetation types. The revegetation priorities are identified as being: sites in the vicinity of existing remnants, riparian areas, and parts of the landscape with diverse land uses and vegetation types. Optimal reconstruction design is affected by opportunity costs due to the loss of agricultural production and the costs of revegetation. 1 Centre for Environmental Economics and Policy, School of Agricultural and Resource Economics, University of Western Australia, Crawley, WA, 6009 2 Department of Primary Industries, Rutherglen, RMB 1145 Chiltern Valley Rd, Rutherglen, Victoria, 3685 3 North Central Catchment Management Authority, PO Box 18, Huntly, Victoria, 3551landscape reconstruction, biodiversity, optimisation, habitat, Environmental Economics and Policy, Land Economics/Use, Q57,
Prioritising investment to enhance biodiversity in an agricultural landscape
The removal, alteration and fragmentation of habitat are key threats to the biodiversity of terrestrial ecosystems. Investment to protect biodiversity assets (e.g. restoration of native vegetation) in dominantly agricultural landscapes usually results in a loss of agricultural production. This can be a significant cost that is often overlooked or poorly addressed in analyses to prioritise such investments. Accounting for this trade-off is important for more successful, realistically feasible and cost-effective biodiversity conservation. We developed a spatially explicit bio-economic optimisation model that simulates the effect of conservation effort on the diversity of woodland-dependent birds in the Avoca catchment (330 thousand ha) in North-Central Victoria. The model minimises opportunity cost of agricultural production and cost of biodiversity conservation effort on a catchment level subject to achieving different levels of biodiversity outcome. We identify the locations and spatial arrangement of conservation efforts that offers the best value for money.Environmental Economics and Policy,
The Structure of Molecular Clouds: I - All Sky Near Infrared Extinction Maps
We are studying the column density distribution of all nearby giant molecular
clouds. As part of this project we generated several all sky extinction maps.
They are calculated using the median near infrared colour excess technique
applied to data from the Two Micron All-Sky Survey (2MASS). Our large scale
approach allows us to fit spline functions to extinction free regions in order
to accurately determine the colour excess values. Two types of maps are
presented: i) Maps with a constant noise and variable spatial resolution; ii)
Maps with a constant spatial resolution and variable noise. Our standard Av map
uses the nearest 49 stars to the centre of each pixel for the determination of
the extinction. The one sigma variance is constant at 0.28mag Av in the entire
map. The distance to the 49th nearest star varies from below 1arcmin near the
Galactic Plane to about 10arcmin at the poles, but is below 5arcmin for all
giant molecular clouds (|b|< 30degr). A comparison with existing large scale
maps shows that our extinction values are systematically larger by 20% compared
to Dobashi et al. and 40% smaller compared to Schlegel et al.. This is most
likely caused by the applied star counting technique in Dobashi et al. and
systematic uncertainties in the dust temperature and emissivity in Schlegel et
al.. Our superior resolution allows us to detect more small scale high
extinction cores compared to the other two maps.Comment: 39 pages, 3 tables, 54 figures, accepted for publication by MNRAS, a
version with higher resolution figures can be found at
http://astro.kent.ac.uk/extinction/index.htm
Dead cetacean? beach, bloat, float, sink
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Moore, M. J., Mitchell, G. H., Rowles, T. K., & Early, G. Dead cetacean? beach, bloat, float, sink. Frontiers in Marine Science, 7, (2020): 333, doi:10.3389/fmars.2020.00333.Variably buoyant, dead Cetacea may float, or sink and later bloat to refloat if ambient temperature and pressure allow sufficient decomposition gas formation and expansion. Mortality can result from acute or chronic disease, fishery entanglement, vessel collision, noxious noises, or toxicant spills. Investigators often face the daunting task of elucidating a complex series of events, in reverse order, from when and where an animal is found, and to diagnose the cause of death. Various scenarios are possible: an animal could die at sea remaining there or floating ashore, or strand on a beach alive, where it dies and, if cast high enough, remain beached to be scavenged or decompose. An animal that rests low on a beach may refloat again, through increased buoyancy from decomposition gas and favorable tides, currents, and wind. Here we review the factors responsible for the different outcomes, and how to recognize the provenance of a cetacean mortality found beached, or floating at sea. In conclusion, only some carcasses strand, or remain floating. Negatively buoyant animals that die at depth, or on the surface, and sink, may never surface, even after decomposition gas accumulation, as in cold, deep waters gas may fail to adequately reduce the density of a carcass, precluding it from returning to the surface
A very luminous, highly extinguished, very fast nova - V1721 Aquilae
Fast novae are primarily located within the plane of the Galaxy, slow novae
are found within its bulge. Because of high interstellar extinction along the
line of sight many novae lying close to the plane are missed and only the
brightest seen. One nova lying very close to the Galactic plane is V1721
Aquilae, discovered in outburst on 2008 September 22. Spectra obtained 2.69
days after outburst revealed very high expansion velocities (FWHM ~6450 km/s).
In this paper we have used available pre- and post-outburst photometry and
post-outburst spectroscopy to conclude that the object is a very fast,
luminous, and highly extinguished A_V=11.6+/-0.2) nova system with an average
ejection velocity of ~3400 km/s. Pre-outburst near-IR colours from 2MASS
indicate that at quiescence the object is similar to many quiescent CNe and
appears to have a main sequence/sub-giant secondary rather than a giant. Based
on the speed of decline of the nova and its emission line profiles we
hypothesise that the axis ratio of the nova ejecta is ~1.4 and that its
inclination is such that the central binary accretion disc is face-on to the
observer. The accretion disc's blue contribution to the system's near-IR
quiescent colours may be significant. Simple models of the nova ejecta have
been constructed using the morphological modelling code XS5, and the results
support the above hypothesis. Spectral classification of this object has been
difficult owing to low S/N levels and high extinction, which has eliminated all
evidence of any He/N or FeII emission within the spectra. We suggest two
possibilities for the nature of V1721 Aql: that it is a U Sco type RN with a
sub-giant secondary or, less likely, that it is a highly energetic bright and
fast classical nova with a main sequence secondary. Future monitoring of the
object for possible RN episodes may be worthwhile, as would archival searches
for previous outbursts.Comment: 9 pages 10 figures, accepted for publication in A&A. Abstract has
been slightly shortened from published versio
Extended H? emission line sources from UWISH2
We present the extended source catalogue for the UKIRT Wide Field Infrared Survey for H2 (UWISH2). The survey is unbiased along the inner Galactic Plane from l ? 357° to l ? 65° and |b| ? 1.5° and covers 209 deg2. A further 42.0 and 35.5 deg2 of high dust column density regions have been targeted in Cygnus and Auriga. We have identified 33 200 individual extended H2 features. They have been classified to be associated with about 700 groups of jets and outflows, 284 individual (candidate) planetary nebulae, 30 supernova remnants and about 1300 photodissociation regions. We find a clear decline of star formation activity (traced by H2 emission from jets and photodissociation regions) with increasing distance from the Galactic Centre. About 60 per cent of the detected candidate planetary nebulae have no known counterpart and 25 per cent of all supernova remnants have detectable H2 emission associated with them
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Pulsed thermal treatment of carbon up to 3000 °C using an atomic absorption spectrometer
An atomic absorption spectrometer unit fitted with a graphite furnace module is used to perform high temperature treatment on three carbonized polymers: polyvinyl chloride (PVC), polyvinylidene chloride (PVDC) and polyacrylonitrile (PAN). Using short pulses up to 45 s, we heat small samples to a maximum of 3000 °C. High-resolution transmission electron microscopy and X-ray diffractometry are used to track the growth of crystallites in the materials as a function of the heating temperature. We observe the well-known behaviour of large crystalline graphite growth in PVC-derived samples and the formation of curved graphitic layers in PVDC- and PAN-derived samples. This graphite furnace atomic absorption spectrometer approach is an attractive alternative to conventional laboratory-scale graphite furnaces in research of high temperature treatment of carbon and other refractory materials
Defining graphenic crystallites in disordered carbon: moving beyond the platelet model
We develop a picture of graphenic crystallites within disordered carbons that
goes beyond the traditional model of graphitic platelets at random orientation.
Using large atomistic models containing one million atoms, we redefine the
meaning of the quantity La extracted from X-ray diffraction (XRD) patterns. Two
complementary approaches are used to measure the size of graphenic
crystallites, which are defined as regions of regularly arranged hexagons.
Firstly, we calculate the X-ray diffraction pattern directly from the atomistic
coordinates of the structure and analyse them following a typical experimental
process. Second, the graphenic crystallites are identified from a direct
geometrical approach. By mapping the structure directly, we replace the
idealised picture of the crystallite with a more realistic representation of
the material and provide a well-defined interpretation for measurements
of disordered carbon. A key insight is that the size distribution is skewed
heavily towards small fragments, with more than 75% of crystallites smaller
than half of
‘If they don't use it, they lose it’: how organisational structures and practices shape residents’ physical movement in care home settings
Older people living in long-term facilities (nursing and residential homes providing 24-hour care) spend the majority of their time inactive, despite the known health and wellbeing benefits of physical activity and reduced time spent sedentary. In order to successfully embed interventions that aim to increase physical activity or reduce sedentary behaviour, it is necessary to understand the features of the care environment that influence residents’ routine patterns of movement. Drawing on an organisational perspective, this paper explores the structures and mechanisms that shaped different care practices concerning residents’ movement in two contrasting care homes in the north of England. This study adopted an ethnographic approach, using a combination of qualitative observations, informal conversations and interviews. A grounded theory approach to data analysis was adopted. The findings illustrate the importance of translating espoused values of care into tangible and acceptable care practices, systems of management, staff training and development, and the use of care planning in residents’ routine patterns of movement. Understanding how organisational factors shape routine movement among care home residents will help inform the development of embedded and sustainable interventions that enhance physical activity and reduce sedentary behaviour. This study is part of a wider programme of research developing and testing a complex intervention, embedded within routine care, to reduce sedentary behaviour among care home residents
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