962 research outputs found
The Age Evolution of the Radio Morphology of Supernova Remnants
Recent hydrodynamical models of supernova remnants (SNRs) demonstrate that
their evolution depends heavily on the inhomogeneities of the surrounding
medium. As SNRs expand, their morphologies are influenced by the non-uniform
and turbulent structure of their environments, as reflected in their radio
continuum emission. In this paper, we measure the asymmetries of 96 SNRs in
radio continuum images from three surveys of the Galactic plane and compare
these results to the SNRs' radii, which we use as a proxy for their age. We
find that larger (older) SNRs are more elliptical/elongated and more mirror
asymmetric than smaller (younger) SNRs, though the latter vary in their degrees
of asymmetry. This result suggests that SNR shells become more asymmetric as
they sweep up the interstellar medium (ISM), as predicted in hydrodynamical
models of SNRs expanding in a multi-phase or turbulent ISM.Comment: 16 pages, 5 figures, accepted by ApJ; sample expanded from 22 to 96
source
We are still not yet out of the woods in W.A.: Western Australia and the international tobacco industry
Castile Evaporite Karst Potential Map of the Gypsum Plain, Eddy County, New Mexico and Culberson County, Texas: A GIS Methodological Comparison
Castile Formation gypsum crops out over ,1,800 km2 in the western Delaware Basin where it forms the majority of the Gypsum Plain. Karst development is well recognized in the Gypsum Plain (i.e., filled and open sinkholes with associated caves); however, the spatial occurrence has been poorly known. In order to evaluate the extent and distribution of karst development within the Castile portion of the Gypsum Plain, combined field and Geographic Information System (GIS) studies were conducted, which enable a first approximation of regional speleogenesis and delineate karst-related natural resources for management. Field studies included physical mapping of 50, 1-km2 sites, including identification of karst features (sinkholes, caves, and springs) and geomorphic mapping. GIS-based studies involved analyses of karst features based on public data, including Digital Elevation Model (DEM), Digital Raster Graphic, (DRG) and Digital Orthophoto Quad (DOQ) formats. GIS analyses consistently underestimate the actual extent and density of karst development, based on karst features identified during field studies. However, DOQ analyses coupled with field studies appears to produce accurate models of karst development. As a result, a karst potential map of the Castile outcrop region was developed which reveals that karst development within the Castile Formation is highly clustered. Approximately 40% of the region effectively exhibits no karst development (,1 feature/km2). Two small regions (,3 km2 each) display intense karst development (.40 features/km2) located within the northern extent of the Gypsum Plain, while many regions of significant karst development (.15 features/km2) are distributed more widely. The clustered distribution of karst development suggests that speleogenesis within the Castile Formation is dominated by hypogenic, transverse processes
Tonic and phasic effects of reward on the pupil:implications for locus coeruleus function
The locus coeruleus (LC), a nucleus in the pons of the brainstem, plays a significant role in attention and cognitive control. Here, we use an adapted auditory oddball paradigm and measured the pupil dilation response, to provide a marker of LC activity in humans. In Experiment 1, we show event-related pupil responses to rare auditory events which were further elevated by task relevant. In Experiment 2, by asking participants to silently count the number of oddballs, we demonstrated that the task-relevance elevation was not a result of the generation or execution of the manual response. In Experiment 3, we observed two separate effects of reward on the pupil response. First, we found an overall increase in pupil area in the high compared to the low-reward blocks: a sustained effect reminiscent of the tonic changes that occur in LC. Second, we found elevated event-related pupil responses to behaviourally relevant stimuli in the high-reward condition compared with the low-reward condition, consistent with phasic changes in LC in response to a stimulus. These results highlight the complexity of the relationship between the pupil response and reward, and the inferred role of LC in both top-down and bottom-up cognitive control
Epigene and Hypogene Karst Manifestations of the Castile Formation: Eddy County, New Mexico and Culberson County, Texas, USA
Permian evaporites of the Castile Formation crop out over ~1,800 km2 in the western Delaware Basin (Eddy County, New Mexico and Culberson County, Texas, USA) with abundant and diverse karst manifestations. Epigene karst occurs as well-developed karren on exposed bedrock, while sinkholes dominate the erosional landscape, including both solutional and collapse forms. Sinkhole analyses suggest that more than half of all sinks are the result of upward stoping of subsurface voids, while many solutional sinks are commonly the result of overprinting of collapsed forms. Epigene caves are laterally limited with rapid aperture decreases away from insurgence, with passages developed along fractures and anticline fold axes. Hypogene karst occurs as diverse manifestations, forming the deepest and longest caves within the region as well as abundant zones of brecciation. Hypogene caves exhibit a wide range of morphologies from complex maze and anastomotic patterns to simple, steeply dipping patterns, but all hypogene caves exhibit morphologic features (i.e. risers, outlet cupolas and half-tubes) that provide a definitive suite of evidence of dissolution within a mixed convection (forced and free convection) hydrologic system. Extensive blanket breccias, abundant breccia pipes and numerous occurrences of calcitized evaporites indicate widespread hypogene speleogenesis throughout the entire Castile Formation. Although most cave and karst development within the Castile outcrop region appears to have hypogene origins, epigene processes are actively overprinting features, creating a complex speleogenetic evolution within the Castile Formation
Seasonal occurrence of fin whale song off Juan Fernandez, Chile
© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Buchan, S. J., Gutierrez, L., Balcazar-Cabrera, N., & Stafford, K. M. Seasonal occurrence of fin whale song off Juan Fernandez, Chile. Endangered Species Research, 39, (2019): 135-145, doi:10.3354/esr00956.Fin whales Balaenoptera physalus were the species of baleen whale most widely caught by commercial whaling fleets off the Chilean coast and are globally classified as Endangered. However, very little is known about the present distribution and seasonal movements of fin whales off the coast of Chile. Passive acoustic data collected at the HA03 station of the Preparatory Commission for the Comprehensive Nuclear Test Ban Treaty Organization off the Juan Fernandez Archipelago (JFA) between 2007 and 2016 were analyzed. The temporal occurrence of fin whale song was examined using automatic detection via spectrogram cross-correlation of song notes and by calculating the average acoustic power in the frequency bands of fin whale song. Fin whale song off JFA was composed of regular 17 Hz notes associated with high-frequency components at 85 Hz, with singlet phrasing at a dominant primary inter-note interval of 14.4 s and a secondary interval of 30.8 s. There was a clear seasonal pattern in acoustic presence that was consistent across all years: low or no song during the austral summer and a peak in song occurrence in austral winter. A propagation loss model estimated the detection range at this site to be 186 km. Where the fin whales that are heard off JFA spend the summer months remains an open question. Possible locations include the Western Antarctic Peninsula and/or off northern-central mainland Chile. Further studies should be pursued to better understand the distribution and seasonal movements and to support the conservation of this Endangered species.We thank the Preparatory Commission for the Comprehensive Nuclear Test Ban Treaty Organization and the Chilean Commission of Nuclear Energy for proving the data used in this study. S.J.B. and N.B.C. were supported by the Center for Oceanographic Research COPAS Sur-Austral, CONICYT PIA PFB31. S.J.B. was also supported during analysis and writing by the Office of Naval Research Global (awards N62909-16-2214 and N00014-17-2606), and a grant to the Centro de Estudios Avanzados enZonas Áridas (CEAZA) ‘Proyecto CEAZA, 3er Fortalec-imiento de Centros Regionales, Programa Regional CONI-CYT R16A10003’. Our greatest thanks to John Hodgson MSc, Technical Director at Ocean Acoustic Developments and Adrian Brown of the Defence Science and Technology Laboratory (UK) for carrying out the propagation modelling free of charge. Many thanks to Rex Andrew for his help with PSD figure preparation in R. Thanks also go to Nathan Merchant for his kind help with PAMGuide. Many thanks to Michael Pitzrick for his guidance with XBAT. Many thanks to the members of the Southern Ocean Research Partnership Blue and Fin Whale Acoustic Trends Working group for useful discussions that improved the quality of this study
Big Tobacco "Pull Out All Stops" for a Landmark Example
Background With the aid of internal tobacco industry documents, this paper provides a chronology of events documenting the role of the Philip Morris tobacco company in the 1993 litigation case against the Burswood International Resort Casino (BIRC). The paper also examines the implications of this case for the regulation of second hand smoke exposure. Method A systematic keyword search and analysis of internal tobacco industry documents was conducted using documents available on the World Wide Web through the Master Settlement Agreement. Results The industry documents provide comprehensive evidence that the Philip Morris tobacco company provided assistance to the BIRC in its defence against action by the Western Australian government. The Philip Morris tobacco company, along with others, sought to publicise and promote the outcome as a ‘landmark example’ to lobby against the implementation of indoor smoking bans. Conclusion Philip Morris’ investment in the BIRC defence demonstrated the industry’s recognition of the potential significance of the case beyond Western Australia. Involvement in the BIRC case assisted the wider tobacco industry by helping to prolong smoking at casinos and other Australian hospitality venues. The findings contribute to our understanding of the history of tobacco industry strategies implemented in Western Australia and internationally to slow tobacco control progress, and the preparedness of the tobacco industry to exploit favourable developments originating anywhere in the world.
New Deal for Disabled People: second synthesis report - interim findings from the evaluation
The New Deal for Disabled People (NDDP) is the major employment programme
available to people claiming incapacity-related benefits, and is an important part of
the Government’s welfare-to-work strategy. NDDP is a voluntary programme that
provides a national network of Job Brokers to help people with health conditions
and disabilities move into sustained employment.
The evaluation design incorporates a longitudinal dimension, and this report
presents selected findings from the evaluation. It covers developments up to and
including spring 2004, and synthesises findings from fieldwork with NDDP
participants, employers, members of the eligible population, those delivering the
programme (notably staff from Job Brokers and Jobcentre Plus offices), and from
administrative data.
There are two recurrent themes running through this report: first, continuity and
change in the programme, the institutions delivering NDDP and in respondents’
views and experiences; and secondly, identifying ‘what works’ in terms of securing
job entries and sustainable employment.
For findings covered in both synthesis reports, Chapter 2 maps the extent to which
there has been continuity and change for selective aspects of NDDP. As might be
expected there are some aspects of NDDP that are unchanged. However, there is
also evidence of change and progression – for example, of improved relationships
between Job Brokers and Jobcentre Plus locally
Increased Psychological Distress during COVID-19 and Quarantine in Ireland: A national survey.
Background: The emergence of the coronavirus pneumonia (COVID-19) resulted in a global pandemic. The psychological impact of an epidemic is multifaceted and acute, with long-term consequences. Methods: A cross-sectional online survey-based design was employed, assessing the psychological impact of COVID-19 on members of the Irish public during the quarantine period of COVID-19 in Ireland. Participants were invited to complete the Depression, Anxiety, and Stress Scale-21 (DASS-21) retrospectively (prior to quarantine) and during the quarantine period, as well as measures of illness perceptions, well-being, and a bespoke measure (the Effects of COVID Questionnaire, ECQ), which assessed perceptions of COVID-related stresses associated with personal concerns, caring for children, caring for aging parents, as well as gratitude. Results: A total of n = 1620 entered the survey platform, with a total of n = 847 surveys completed by members of the Irish public. Entry into COVID-19 quarantine was associated with significant increases in clinically significant symptoms of depression, stress, and anxiety. The ECQ reliably assessed a range of COVID-19-related stresses and had large and significant correlations with the DASS-21. Conclusions: The COVID-19 quarantine was associated with stresses and significant increases in symptoms of depression, anxiety, and stress in a national Irish cohort. The public require increased access to mental health services to meet this increase in COVID-19-related psychological distress
Epigene and hypogene gypsum karst manifestations of the Castile Formation: Eddy County, New Mexico and Culberson County, Texas, USA
Pikara Magazine es un medio de comunicación fundado por cuatro periodistas vascas: June Fernández, Lucía Martínez Odriozola, Itziar Abad y Maite Asensio. Todas formaban parte de la Red Vasca de Periodistas con Visión de Género- Kazetarion Berdinsarea. Los objetivos de la red pasaban por lograr introducir la perspectiva de género en las prácticas periodistas de los medios de comunicación, que tienden al androcentrismo. Esos mismos objetivos rigen Pikara Magazine
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