1,456 research outputs found
Addressing Ethical Issues in Studying Menâs Traumatic Stress
Like many human experiences, traumatic stress is highly gendered. Over the past several decades, a sub-stantial number of empirical studies have explored ethical issues in traumatic stress research. However, these studies have typically reported female samples or failed to account for the influence of gender in their analyses of mixed-sex samples. By extension, ethical issues that are relevant to male participants in traumatic stress research are poorly understood. After briefly exploring why the vulnerabilities of male participants are under-explored in traumatic stress research, this article highlights many ethical issues that are important to address when men participate in traumatic stress research, concluding with some sugges-tions for how these might be taken up to advance the field
The Near-Infrared Extinction Law in Regions of High Av
We present a spectroscopic study of the shape of the dust-extinction law
between 1.0 and 2.2um towards a set of nine ultracompact HII regions with Av >
15 mag. We find some evidence that the reddening curve may tend to flatten at
higher extinctions, but just over half of the sample has extinction consistent
with or close to the average for the interstellar medium. There is no evidence
of extinction curves significantly steeper than the standard law, even where
water ice is present. Comparing the results to the predictions of a simple
extinction model, we suggest that a standard extinction law implies a robust
upper limit to the grain-size distribution at around 0.1 - 0.3um. Flatter
curves are most likely due to changes in this upper limit, although the effects
of flattening due to unresolved clumpy extinction cannot be ruled out.Comment: 9 pages, 7 figure
Helium and Hydrogen Line Ratios and The Stellar Content of Compact HII Regions
We present observations and models of the behaviour of the HI and HeI lines
between 1.6 and 2.2um in a small sample of compact HII regions. As in our
previous papers on planetary nebulae, we find that the `pure' 1.7007um
4^3D-3^3P and 2.16475um 7^(3,1)G-4^(3,1)F HeI recombination lines behave
approximately as expected as the effective temperature of the central exciting
star(s) increases. However, the 2.058um 2^1P-2^1S HeI line does not behave as
the model predicts, or as seen in planetary nebulae. Both models and planetary
nebulae showed a decrease in the HeI 2^1P-2^1S/HI Br gamma ratio above an
effective temperature of 40000K. The compact HII regions do not show any such
decrease. The problem with this line ratio is probably due to the fact that the
photoionisation model does not account correctly for the high densities seen in
these HII regions, and that we are therefore seeing more collisional excitation
of the 2^1P level than the model predicts. It may also reflect some deeper
problem in the assumed model stellar atmospheres. In any event, although the
normal HeI recombination lines can be used to place constraints on the
temperature of the hottest star present, the HeI 2^1P-2^1S/HI Br gamma ratio
should not be used for this purpose in either Galactic HII regions or in
starburst galaxies, and conclusions from previous work using this ratio should
be regarded with extreme caution. We also show that the combination of the near
infrared `pure' recombination line ratios with mid-infrared forbidden line data
provides a good discriminant of the form of the far ultraviolet spectral energy
distribution of the exciting star(s). From this we conclude that CoStar models
are a poor match to the available data for our sources, though the more recent
WM-basic models are a better fit.Comment: Accepted for publication in MNRA
Added Value Report: University of Westminster Transformation in Students Project
One of the core aims that all Higher Education institutions share is to enhance graduate employability, and develop a workforce that is ready for the constantly changing labour market. While the concept of employability is shifting and variable (e.g. students as âcustomersâ and/or âpartnersâ (Skea, 2017), it is necessary to develop inclusive measures of employability that can extend beyond generic skills, and include values and identity-driven attributes. The literature recognises that graduate attributes are a set of desirable skills, qualities and understandings that both the University and students deem as important for employment and for shaping identities within the labour market (OâLeary, 2016; Bridgstock, 2009; Tomlinson, 2007). Thus, focus groups and interviews were carried out with undergraduates, postgraduates and alumni to explore their experiences at the University of Westminster, and to elicit the values and qualities that they consider important and personally valuable to their success in the future. This report presents qualitative findings on studentsâ experiences of gaining âadded valueâ from their time at Westminster. Subsequently, we will use the results to create a robust survey that gives a scientific measurement of studentsâ attribute development throughout their studies at University
The role of BoFLC2 in cauliflower (Brassica oleracea var. botrytis L.) reproductive development
In agricultural species that are sexually propagated or whose marketable organ is a reproductive structure, management of the flowering process is critical. Inflorescence development in cauliflower is particularly complex, presenting unique challenges for those seeking to predict and manage flowering time. In this study, an integrated physiological and molecular approach was used to clarify the environmental control of cauliflower reproductive development at the molecular level. A functional allele of BoFLC2 was identified for the first time in an annual brassica, along with an allele disrupted by a frameshift mutation (boflc2). In a segregating F2 population derived from a cross between late-flowering (BoFLC2) and early-flowering (boflc2) lines, this gene behaved in a dosage-dependent manner and accounted for up to 65% of flowering time variation. Transcription of BoFLC genes was reduced by vernalization, with the floral integrator BoFT responding inversely. Overall expression of BoFT was significantly higher in early-flowering boflc2 lines, supporting the idea that BoFLC2 plays a key role in maintaining the vegetative state. A homologue of Arabidopsis VIN3 was isolated for the first time in a brassica crop species and was up-regulated by two days of vernalization, in contrast to findings in Arabidopsis where prolonged exposure to cold was required to elicit up-regulation. The correlations observed between gene expression and flowering time in controlled-environment experiments were validated with gene expression analyses of cauliflowers grown outdoors under 'natural' vernalizing conditions, indicating potential for transcript levels of flowering genes to form the basis of predictive assays for curd initiation and flowering time
The role of BoFLC2 in cauliflower (Brassica oleracea var. botrytis L.) reproductive development
In agricultural species that are sexually propagated or whose marketable organ is a reproductive structure, management of the flowering process is critical. Inflorescence development in cauliflower is particularly complex, presenting unique challenges for those seeking to predict and manage flowering time. In this study, an integrated physiological and molecular approach was used to clarify the environmental control of cauliflower reproductive development at the molecular level. A functional allele of BoFLC2 was identified for the first time in an annual brassica, along with an allele disrupted by a frameshift mutation (boflc2). In a segregating F2 population derived from a cross between late-flowering (BoFLC2) and early-flowering (boflc2) lines, this gene behaved in a dosage-dependent manner and accounted for up to 65% of flowering time variation. Transcription of BoFLC genes was reduced by vernalization, with the floral integrator BoFT responding inversely. Overall expression of BoFT was significantly higher in early-flowering boflc2 lines, supporting the idea that BoFLC2 plays a key role in maintaining the vegetative state. A homologue of Arabidopsis VIN3 was isolated for the first time in a brassica crop species and was up-regulated by two days of vernalization, in contrast to findings in Arabidopsis where prolonged exposure to cold was required to elicit up-regulation. The correlations observed between gene expression and flowering time in controlled-environment experiments were validated with gene expression analyses of cauliflowers grown outdoors under 'natural' vernalizing conditions, indicating potential for transcript levels of flowering genes to form the basis of predictive assays for curd initiation and flowering time
Turbulence driven by outflow-blown cavities in the molecular cloud of NGC 1333
Outflows from young stellar objects have been identified as a possible source
of turbulence in molecular clouds. To investigate the relationship between
outflows, cloud dynamics and turbulence, we compare the kinematics of the
molecular gas associated with NGC 1333, traced in 13CO(1-0), with the
distribution of young stellar objects (YSOs) within. We find a velocity
dispersion of ~ 1-1.6 km/s in 13CO that does not significantly vary across the
cloud, and is uncorrelated with the number of nearby young stellar outflows
identified from optical and submillimeter observations. However, from velocity
channel maps we identify about 20 cavities or depressions in the 13CO intensity
of scales > 0.1-0.2 pc and velocity widths 1-3 km/s. The cavities exhibit limb
brightened rims in both individual velocity channel maps and position velocity
diagrams, suggesting that they are slowly expanding. We interpret these
cavities to be remnants of past YSO outflow activity: If these cavities are
presently empty, they would fill in on time scales of a million years. This can
exceed the lifetime of a YSO outflow phase, or the transit time of the central
star through the cavity, explaining the the absence of any clear correlation
between the cavities and YSO outflows. We find that the momentum and energy
deposition associated with the expansion of the cavities is sufficient to power
the turbulence in the cloud. In this way we conclude that the cavities are an
important intermediary step between the conversion of YSO outflow energy and
momentum into cloud turbulent motions.Comment: Accepted for publication in ApJ. Check out
http://astro.pas.rochester.edu/~aquillen/coolpics.html for channel map and
PosVel movies of N133
The Gas Temperature of Starless Cores in Perseus
In this paper we study the determinants of starless core temperatures in the
Perseus molecular cloud. We use NH3 (1,1) and (2,2) observations to derive core
temperatures (T_kin) and data from the COMPLETE Survey of Star Forming Regions
and the c2d Spitzer Legacy Survey for observations of the other core and
molecular cloud properties. The kinetic temperature distribution probed by NH3
is in the fairly narrow range of 9 - 15 K. We find that cores within the
clusters IC348 and NGC1333 are significantly warmer than "field" starless
cores, and T_kin is higher within regions of larger extinction-derived column
density. Starless cores in the field are warmer when they are closer to class
O/I protostars, but this effect is not seen for those cores in clusters. For
field starless cores, T_kin is higher in regions in which the 13CO linewidth
and the 1.1mm flux from the core are larger, and T_kin is lower when the the
peak column density within the core and average volume density of the core are
larger. There is no correlation between T_kin and 13CO linewidth, 1.1mm flux,
density or peak column density for those cores in clusters. The temperature of
the cloud material along the line of sight to the core, as measured by CO or
far-infrared emission from dust, is positively correlated with core temperature
when considering the collection of cores in the field and in clusters, but this
effect is not apparent when the two subsamples of cores are considered
separately.Comment: Accepted to ApJ; 13 pages, including 3 tables and three figure
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