630 research outputs found
Finding their Fit: An Exploratory Study of Interpreters’ Perceptions of their Membership in the Deaf Community
In the U.S., Deaf individuals who use a signed language as their preferred and dominant means of communication are considered a distinct linguistic and cultural group known as the Deaf community. Sign language interpreters, particularly non-native signers who are leaning ASL, are frequently encouraged to associate with the Deaf community as part of their language acquisition process. However, interpreters who are not deaf or native signers, especially students, often experience tension as they interact with the Deaf community. The literature is divided on whether hearing interpreters who learn ASL later in life, even those who are arguably bilingual and bicultural, are able to attain Deaf community membership. The guiding questions for this study are: According to their own perspectives, can hearing, ASL-English interpreters be members of the Deaf community? If they are members, what qualifies them as members, and if not, why not? Three interpreters were interviewed to elicit their views on hearing interpreters’ fit within the Deaf community. Qualitative analysis in ELAN uncovered three primary themes; participants’ definition of Deaf community and who can be a member, what participants’ saw as requirements for interpreter membership, and caveats to such membership. While ASL fluency, attitude, and cultural competency were found to be important, a key finding is that participants agree interpreters’ membership is dependent upon the Deaf community extending an invitation and is not something they can claim for themselves
Large Interstellar Polarisation Survey, II : UV/optical study of cloud-to-cloud variations of dust in the diffuse ISM
It is well known that the dust properties of the diffuse interstellar medium exhibit variations towards different sight-lines on a large scale. We have investigated the variability of the dust characteristics on a small scale, and from cloud-to-cloud. We use low-resolution spectro-polarimetric data obtained in the context of the Large Interstellar Polarisation Survey (LIPS) towards 59 sight-lines in the Southern Hemisphere, and we fit these data using a dust model composed of silicate and carbon particles with sizes from the molecular to the sub-micrometre domain. Large (>= 6 nm) silicates of prolate shape account for the observed polarisation. For 32 sight-lines we complement our data set with UVES archive high-resolution spectra, which enable us to establish the presence of single-cloud or multiple-clouds towards individual sight-lines. We find that the majority of these 35 sight-lines intersect two or more clouds, while eight of them are dominated by a single absorbing cloud. We confirm several correlations between extinction and parameters of the Serkowski law with dust parameters, but we also find previously undetected correlations between these parameters that are valid only in single-cloud sight-lines. We find that interstellar polarisation from multiple-clouds is smaller than from single-cloud sight-lines, showing that the presence of a second or more clouds depolarises the incoming radiation. We find large variations of the dust characteristics from cloud-to-cloud. However, when we average a sufficiently large number of clouds in single-cloud or multiple-cloud sight-lines, we always retrieve similar mean dust parameters. The typical dust abundances of the single-cloud cases are [C]/[H] = 92 ppm and [Si]/[H] = 20 ppm
Large Interstellar Polarisation Survey II. UV/optical study of cloud-to-cloud variations of dust in the diffuse ISM
It is well known that the dust properties of the diffuse interstellar medium
exhibit variations towards different sight-lines on a large scale. We have
investigated the variability of the dust characteristics on a small scale, and
from cloud-to-cloud. We use low-resolution spectro-polarimetric data obtained
in the context of the Large Interstellar Polarisation Survey (LIPS) towards 59
sight-lines in the Southern Hemisphere, and we fit these data using a dust
model composed of silicate and carbon particles with sizes from the molecular
to the sub-micrometre domain. Large (> 6 nm) silicates of prolate shape account
for the observed polarisation. For 32 sight-lines we complement our data set
with UVES archive high-resolution spectra, which enable us to establish the
presence of single-cloud or multiple-clouds towards individual sight-lines. We
find that the majority of these 35 sight-lines intersect two or more clouds,
while eight of them are dominated by a single absorbing cloud. We confirm
several correlations between extinction and parameters of the Serkowski law
with dust parameters, but we also find previously undetected correlations
between these parameters that are valid only in single-cloud sight-lines. We
find that interstellar polarisation from multiple-clouds is smaller than from
single-cloud sight-lines, showing that the presence of a second or more clouds
depolarises the incoming radiation. We find large variations of the dust
characteristics from cloud-to-cloud. However, when we average a sufficiently
large number of clouds in single-cloud or multiple-cloud sight-lines, we always
retrieve similar mean dust parameters. The typical dust abundances of the
single-cloud cases are [C]/[H] = 92 ppm and [Si]/[H] = 20 ppm.Comment: A&A accepte
Differential Mating Success of Male Wing Morphs of the Cricket, \u3ci\u3eGryllus rubens\u3c/i\u3e
Genetically marked individuals were used to study differential mating success between male wing morphs of the cricket, Gryllus rubens. Previous studies of Gryllus rubens and other wing-dimorphic insects have documented that flightless short-winged or wingless females typically attain reproductive maturity earlier and oviposit more eggs relative to their long-winged counterparts. This study was done to determine if flightless males also exhibit enhanced reproductive characteristics. Segregation analyses documented the genetic basis of allozymes used to infer paternity in subsequent experiments. Control experiments documented the absence of effects on mating success independent of wing morph due to (1) the genetic stock from which males were taken; (2) male size; or (3) female wing morph. Mating trials involving a long-winged male, a short-winged male and a female of either wing morph documented no significant differences in the number of progeny sired by male wing morphs. This pattern was true for both the first group of offspring and for the entire set of offspring produced during a 20-day period. Thus, in contrast to females, we observed no increase in reproductive output in males resulting from the loss of the flight apparatus. However, substantial variance in mating success was observed between males independent of wing morph. This result was likely due to the existence of a dominance hierarchy and the increased mating success of the dominant male
Differential Mating Success of Male Wing Morphs of the Cricket, \u3ci\u3eGryllus rubens\u3c/i\u3e
Genetically marked individuals were used to study differential mating success between male wing morphs of the cricket, Gryllus rubens. Previous studies of Gryllus rubens and other wing-dimorphic insects have documented that flightless short-winged or wingless females typically attain reproductive maturity earlier and oviposit more eggs relative to their long-winged counterparts. This study was done to determine if flightless males also exhibit enhanced reproductive characteristics. Segregation analyses documented the genetic basis of allozymes used to infer paternity in subsequent experiments. Control experiments documented the absence of effects on mating success independent of wing morph due to (1) the genetic stock from which males were taken; (2) male size; or (3) female wing morph. Mating trials involving a long-winged male, a short-winged male and a female of either wing morph documented no significant differences in the number of progeny sired by male wing morphs. This pattern was true for both the first group of offspring and for the entire set of offspring produced during a 20-day period. Thus, in contrast to females, we observed no increase in reproductive output in males resulting from the loss of the flight apparatus. However, substantial variance in mating success was observed between males independent of wing morph. This result was likely due to the existence of a dominance hierarchy and the increased mating success of the dominant male
Herschel PACS and SPIRE spectroscopy of the Photodissociation Regions associated with S 106 and IRAS 23133+6050
Photodissociation regions (PDRs) contain a large fraction of all of the
interstellar matter in galaxies. Classical examples include the boundaries
between ionized regions and molecular clouds in regions of massive star
formation, marking the point where all of the photons energetic enough to
ionize hydrogen have been absorbed. In this paper we determine the physical
properties of the PDRs associated with the star forming regions IRAS 23133+6050
and S 106 and present them in the context of other Galactic PDRs associated
with massive star forming regions. We employ Herschel PACS and SPIRE
spectroscopic observations to construct a full 55-650 {\mu}m spectrum of each
object from which we measure the PDR cooling lines, other fine- structure
lines, CO lines and the total far-infrared flux. These measurements are then
compared to standard PDR models. Subsequently detailed numerical PDR models are
compared to these predictions, yielding additional insights into the dominant
thermal processes in the PDRs and their structures. We find that the PDRs of
each object are very similar, and can be characterized by a two-phase PDR model
with a very dense, highly UV irradiated phase (n 10^6 cm^(-3), G
10^5) interspersed within a lower density, weaker radiation field phase
(n 10^4 cm^(-3), G 10^4). We employed two different numerical
models to investigate the data, firstly we used RADEX models to fit the peak of
the CO ladder, which in conjunction with the properties derived yielded
a temperature of around 300 K. Subsequent numerical modeling with a full PDR
model revealed that the dense phase has a filling factor of around 0.6 in both
objects. The shape of the CO ladder was consistent with these components
with heating dominated by grain photoelectric heating. An extra excitation
component for the highest J lines (J > 20) is required for S 106.Comment: 20 pages, 10 figures, A&A Accepte
A Dust Twin of Cas A: Cool Dust and 21-micron Silicate Dust Feature in the Supernova Remnant G54.1+0.3
We present infrared (IR) and submillimeter observations of the Crab-like
supernova remnant (SNR) G54.1+0.3 including 350 micron (SHARC-II), 870 micron
(LABOCA), 70, 100, 160, 250, 350, 500 micron (Herschel) and 3-40 micron
(Spitzer). We detect dust features at 9, 11 and 21 micron and a long wavelength
continuum dust component. The 21 micron dust coincides with [Ar II] ejecta
emission, and the feature is remarkably similar to that in Cas A. The IRAC 8
micron image including Ar ejecta is distributed in a shell-like morphology
which is coincident with dust features, suggesting that dust has formed in the
ejecta. We create a cold dust map that shows excess emission in the
northwestern shell. We fit the spectral energy distribution of the SNR using
the continuous distributions of ellipsoidal (CDE) grain model of pre-solar
grain SiO2 that reproduces the 21 and 9 micron dust features and discuss grains
of SiC and PAH that may be responsible for the 10-13 micron dust features. To
reproduce the long-wavelength continuum, we explore models consisting of
different grains including Mg2SiO4, MgSiO3, Al2O3, FeS, carbon, and Fe3O4. We
tested a model with a temperature-dependent silicate absorption coefficient. We
detect cold dust (27-44 K) in the remnant, making this the fourth such SNR with
freshly-formed dust. The total dust mass in the SNR ranges from 0.08-0.9 Msun
depending on the grain composition, which is comparable to predicted masses
from theoretical models. Our estimated dust masses are consistent with the idea
that SNe are a significant source of dust in the early Universe.Comment: MNRAS: accepted on June 28, 2018 and published on July 4, 201
- …