2,734 research outputs found
The Spread of Country Music to an Urban Setting Seen Through the Spread of Dance Halls
Country music has become one of the most popular genres of music in today\u27s world. A genre that grew out of the rural societies of America, its popularity has spread into the urban setting and has influenced social life there as well. This poses a question about whether country music has a become more popular in an urban/suburban setting versus a rural setting. There has been a large increase in country music\u27s popularity in an urban setting and it is where the genre is becoming more popular. The spread of country music will be represented by country music dance halls and their proximity to city centers. The data will be collected using primary literature and country music dance hall databases. Results will be displayed using GIS software to show whether dance halls are more popular in an urban or rural setting
An Examination of Strategies to Mitigate the Number of Motorcycle Rider Fatalities in Thailand
This paper attempts to examine and quantify the degree of safety-helmet use by motorcyclists and their passengers in Thailand. Specifically, the paper examines the phenomena in three separate locations within Thailand. The paper will also review the literature surrounding road safety in general, road safety for motorcyclists, proper helmet use, Thai acts of parliament aimed at motorcyclists, and the degree to which helmet use is enforced or policed in Thailand. Experts posit that road fatalities, and the serious debilitating injuries caused by road traffic accidents, can impact a nation’s GDP by as much as 5%. Perhaps even more importantly, especially in the context of a developing country, is the direct impact to families who lose their prime bread-winner or wage-earner. This loss may either be permanent, as in the case of a fatality, or extended over a protracted period of time, where families find themselves having to care for severely injured members. In the latter case, the requirement for care is often long-term, with little in the way of insurance or medical benefits to offset the burden. It is hoped that a study of motorcycle related road traffic fatalities may identify or highlight interventions or strategies that could be employed to mitigate the road toll in Thailand
Multiple incursion pathways for Helicoverpa armigera in Brazil show its genetic diversity spreading in a connected world
The Old World cotton bollworm Helicoverpa armigera was first detected in Brazil with subsequent reports from Paraguay, Argentina, Bolivia, and Uruguay. This pattern suggests that the H. armigera spread across the South American continent following incursions into northern/central Brazil, however, this hypothesis has not been tested. Here we compare northern and central Brazilian H. armigera mtDNA COI haplotypes with those from southern Brazil, Uruguay, Argentina, and Paraguay. We infer spatial genetic and gene flow patterns of this dispersive pest in the agricultural landscape of South America. We show that the spatial distribution of H. armigera mtDNA haplotypes and its inferred gene flow patterns in the southwestern region of South America exhibited signatures inconsistent with a single incursion hypothesis. Simulations on spatial distribution patterns show that the detection of rare and/or the absence of dominant mtDNA haplotypes in southern H. armigera populations are inconsistent with genetic signatures observed in northern and central Brazil. Incursions of H. armigera into the New World are therefore likely to have involved independent events in northern/central Brazil, and southern Brazil/Uruguay-Argentina-Paraguay. This study demonstrates the significant biosecurity challenges facing the South American continent, and highlights alternate pathways for introductions of alien species into the New World
MRK 1216 & NGC 1277 - An orbit-based dynamical analysis of compact, high velocity dispersion galaxies
We present a dynamical analysis to infer the structural parameters and
properties of the two nearby, compact, high velocity dispersion galaxies
MRK1216 & NGC1277. Combining deep HST imaging, wide-field IFU stellar
kinematics, and complementary long-slit spectroscopic data out to 3 R_e, we
construct orbit-based models to constrain their black hole masses, dark matter
content and stellar mass-to-light ratios. We obtain a black hole mass of
log(Mbh/Msun) = 10.1(+0.1/-0.2) for NGC1277 and an upper limit of log(Mbh/Msun)
= 10.0 for MRK1216, within 99.7 per cent confidence. The stellar mass-to-light
ratios span a range of Upsilon_V = 6.5(+1.5/-1.5) in NGC1277 and Upsilon_H =
1.8(+0.5/-0.8) in MRK1216 and are in good agreement with SSP models of a single
power-law Salpeter IMF. Even though our models do not place strong constraints
on the dark halo parameters, they suggest that dark matter is a necessary
ingredient in MRK1216, with a dark matter contribution of 22(+30/-20) per cent
to the total mass budget within 1 R_e. NGC1277, on the other hand, can be
reproduced without the need for a dark halo, and a maximal dark matter fraction
of 13 per cent within the same radial extent. In addition, we investigate the
orbital structures of both galaxies, which are rotationally supported and
consistent with photometric multi-S\'ersic decompositions, indicating that
these compact objects do not host classical, non-rotating bulges formed during
recent (z <= 2) dissipative events or through violent relaxation. Finally, both
MRK 1216 and NGC 1277 are anisotropic, with a global anisotropy parameter delta
of 0.33 and 0.58, respectively. While MRK 1216 follows the trend of
fast-rotating, oblate galaxies with a flattened velocity dispersion tensor in
the meridional plane of the order of beta_z = delta, NGC 1277 is highly
tangentially anisotropic and seems to belong kinematically to a distinct class
of objects.Comment: 27 pages, 15 figures and 4 tables. Accepted for publication in MNRA
The Black Hole in the Compact, High-dispersion Galaxy NGC 1271
Located in the Perseus cluster, NGC 1271 is an early-type galaxy with a small
effective radius of 2.2 kpc and a large stellar velocity dispersion of 276 km/s
for its K-band luminosity of 8.9x10^{10} L_sun. We present a mass measurement
for the black hole in this compact, high-dispersion galaxy using observations
from the integral field spectrograph NIFS on the Gemini North telescope
assisted by laser guide star adaptive optics, large-scale integral field unit
observations with PPAK at the Calar Alto Observatory, and Hubble Space
Telescope WFC3 imaging observations. We are able to map out the stellar
kinematics on small spatial scales, within the black hole sphere of influence,
and on large scales that extend out to four times the galaxy's effective
radius. We find that the galaxy is rapidly rotating and exhibits a sharp rise
in the velocity dispersion. Through the use of orbit-based stellar dynamical
models, we determine that the black hole has a mass of (3.0^{+1.0}_{-1.1}) x
10^9 M_sun and the H-band stellar mass-to-light ratio is 1.40^{+0.13}_{-0.11}
M_sun/L_sun (1-sigma uncertainties). NGC 1271 occupies the sparsely-populated
upper end of the black hole mass distribution, but is very different from the
Brightest Cluster Galaxies (BCGs) and giant elliptical galaxies that are
expected to host the most massive black holes. Interestingly, the black hole
mass is an order of magnitude larger than expectations based on the galaxy's
bulge luminosity, but is consistent with the mass predicted using the galaxy's
bulge stellar velocity dispersion. More compact, high-dispersion galaxies need
to be studied using high spatial resolution observations to securely determine
black hole masses, as there could be systematic differences in the black hole
scaling relations between these types of galaxies and the BCGs/giant
ellipticals, thereby implying different pathways for black hole and galaxy
growth.Comment: accepted for publication in Ap
Optimising the choice of analysis method for all-sky searches for continuous gravitational waves with Einstein@Home
Rapidly rotating neutron stars are promising sources of continuous
gravitational waves for the LIGO and Virgo observatories. The majority of
neutron stars in our galaxy have not been identified with electromagnetic
observations. Blind all-sky searches offer the potential to detect
gravitational waves from these unidentified sources. The parameter space of
these searches presents a significant computational challenge. Various methods
have been designed to perform these searches with available computing
resources. Recently, a method called Weave has been proposed to achieve
template placement with a minimal number of templates. We employ a mock data
challenge to assess the ability of this method to recover signals, and compare
its sensitivity with that of the global correlation transform method (GCT),
which has been used for searches with the Einstein@Home volunteer computing
project for a number of years. We find that the Weave method is 14% more
sensitive for an all-sky search on Einstein@Home, with a sensitivity depth of
1/ at 90% detection efficiency, compared to
1/ for GCT. This corresponds to a 50% increase
in the volume of sky where we are sensitive with the Weave search. We also find
that the Weave search recovers candidates closer to the true signal position.
In the search studied here the improvement in candidate localisation would lead
to a factor of 70 reduction in the computing cost required to follow up the
same number of candidates. We assess the feasability of deploying the search on
Einstein@Home, and find that Weave requires more memory than is typically
available on a volunteer computer. We conclude that, while GCT remains the best
choice for deployment on Einstein@Home due to its lower memory requirements,
Weave presents significant advantages for the subsequent hierarchical follow-up
of interesting candidates.Comment: 12 pages, 5 figure
The structural and dynamical properties of compact elliptical galaxies
Dedicated photometric and spectroscopic surveys have provided unambiguous
evidence for a strong stellar mass-size evolution of galaxies within the last
10 Gyr. The likely progenitors of today's most massive galaxies are remarkably
small, disky, passive and have already assembled much of their stellar mass at
redshift z=2. An in-depth analysis of these objects, however, is currently not
feasible due to the lack of high-quality, spatially-resolved photometric and
spectroscopic data. In this paper, we present a sample of nearby compact
elliptical galaxies (CEGs), which bear resemblance to the massive and quiescent
galaxy population at earlier times. Hubble Space Telescope (HST) and wide-field
integral field unit (IFU) data have been obtained, and are used to constrain
orbit-based dynamical models and stellar population synthesis (SPS) fits, to
unravel their structural and dynamical properties. We first show that our
galaxies are outliers in the present-day stellar mass-size relation. They are,
however, consistent with the mass-size relation of compact, massive and
quiescent galaxies at redshift z=2. The compact sizes of our nearby galaxies
imply high central stellar mass surface densities, which are also in agreement
with the massive galaxy population at higher redshift, hinting at strong
dissipational processes during their formation. Corroborating evidence for a
largely passive evolution within the last 10 Gyr is provided by their orbital
distribution as well as their stellar populations, which are difficult to
reconcile with a very active (major) merging history. This all supports that we
can use nearby CEGs as local analogues of the high-redshift, massive and
quiescent galaxy population, thus providing additional constraints for models
of galaxy formation and evolution.Comment: 33 pages, 27 figures and 20 tables (with most of the tables provided
as online-only supporting information). Accepted for publication in MNRA
Population structure and gene flow in the global pest, Helicoverpa armigera
Helicoverpa armigerais a major agricultural pest that is distributed across Europe, Asia, Africa and Australasia. This species is hypothesized to have spread to the Americas 1.5million years ago, founding a population that is at present, a distinct species,Helicoverpa zea. In 2013,H.armigerawas confirmed to have re-entered South America via Brazil and subsequently spread. The source of the recent incursion is unknown and population structure inH.armigerais poorly resolved, but a basic understanding would highlight potential biosecurity failures and determine the recent evolutionary history of region-specific lineages. Here, we integrate several end points derived from high-throughput sequencing to assess gene flow inH.armigeraandH.zeafrom populations across six continents. We first assemble mitochondrial genomes to demonstrate the phylogenetic relationship ofH.armigerawith other Heliothine species and the lack of distinction between populations. We subsequently usede novogenotyping-by-sequencing and whole-genome sequences aligned to bacterial artificial chromosomes, to assess levels of admixture. Primarily, we find that BrazilianH.armigeraare derived from diverse source populations, with strong signals of gene flow from European populations, as well as prevalent signals of Asian and African ancestry. We also demonstrate a potential field-caught hybrid betweenH.armigeraandH.zea,and are able to provide genomic support for the presence of theH.armigera confertasubspecies in Australasia. While structure among the bulk of populations remains unresolved, we present distinctions that are pertinent to future investigations as well as to the biosecurity threat posed byH.armigera
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