192 research outputs found
Transitional YSOs: Candidates from Flat-Spectrum IRAS Sources
We are searching for Young Stellar Objects (YSOs) near the boundary between
protostars and pre-main sequence objects, what we have termed transitional
YSOs. We have identified a sample of 125 objects as candidate transitional YSOs
on the basis of IRAS colors and optical appearance on DSS images. We find that
the majority of our objects are associated with star-forming regions,
confirming our expectation that the bulk of these are YSOs.
We present optical, near-IR and high-resolution IRAS images of 92 objects
accessible from the northern and 62 from the southern hemisphere. The objects
have been classified on the basis of their morphology and spectral index. Of
the 125 objects, 28 have a variety of characteristics very similar to other
transitional YSOs, while another 22 show some of these characteristics,
suggesting that these transitional YSOs are not as rare as predicted by theory.Comment: 4 pages, 3 figures, to appear in proc. 33rd ESLAB Symposium ``Star
Formation from the Small to the Large Scale'', eds. F. Favata et al., ESA
SP-44
On the way to adult identity: An evaluation of identity status and narrative identity models of development
Successful resolution of identity is fundamental for a good life. According to the ego identity status model, emerging adults explore and commit to various identity domains. Concurrently, emerging adults are theorized to develop their narrative identity. Yet, it is unclear whether ego identity processes help to establish a narrative identity, or if the development of a narrative identity facilitates ego identity achievement. Therefore, we assessed autobiographical meaning making in repeated narratives and identity status processes of 180 emerging adults (M age = 20.47, SD age = 3.35, 68.90 % female) at two measurements 8-months apart. Results showed differential effects on identity depending on the meaning made and suggest that narrative identity provides the ground for identity status processes such as identity exploration
Salivary gland-specific <i>P. berghei</i> reporter lines enable rapid evaluation of tissue-specific sporozoite loads in mosquitoes
Malaria is a life-threatening human infectious disease transmitted by mosquitoes. Levels of the salivary gland sporozoites (sgs), the only mosquito stage infectious to a mammalian host, represent an important cumulative index of <i>Plasmodium</i> development within a mosquito. However, current techniques of sgs quantification are laborious and imprecise. Here, transgenic <i>P. berghei</i> reporter lines that produce the green fluorescent protein fused to luciferase (GFP-LUC) specifically in sgs were generated, verified and characterised. Fluorescence microscopy confirmed the sgs stage specificity of expression of the reporter gene. The luciferase activity of the reporter lines was then exploited to establish a simple and fast biochemical assay to evaluate sgs loads in whole mosquitoes. Using this assay we successfully identified differences in sgs loads in mosquitoes silenced for genes that display opposing effects on <i>P. berghei</i> ookinete/oocyst development. It offers a new powerful tool to study infectivity of <i>P. berghei</i> to the mosquito, including analysis of vector-parasite interactions and evaluation of transmission-blocking vaccines
Exploring the Application of NLP in Narrative Patterns of Adult Attachment
The Adult Attachment Interview (AAI) is a protocol-based, semi-structured interview method widely used to measure adults’ states of mind with respect to attachment. Recently, transcripts of this interview have been used to code secure base script knowledge, which is script-like knowledge related to the way parents dealt with their distress during childhood (ie., child went to parent for comfort, parent provided instrumental and emotional support, child went back to play). Manually coding the verbatim transcripts is labor-intensive and requires a lot of centralized training. The potential integration of machine learning and natural language processing (NLP) techniques may automate certain aspects of AAI analysis, potentially optimizing the process. The aim of this research project is to explore the practical application of these technologies in analyzing AAI transcripts.The project uses data from a pooled set of 12 studies originating from four countries. Upon reviewing the 1,410 AAI transcripts in this set (conducted in three languages), notable discrepancies in the administration of the interviews emerged, some of which may affect the suitability of the interview to assess secure base script knowledge. The first focus of this research project is therefore to develop a model to automatically assess the quality of the transcripts, first for English studies and then for all studies and languages. This model will prioritize evaluating interview characteristics, including instances of unintelligibility and non-adherence to the prescribed AAI protocol. As a next step in the project, employing sentiment analysis will enable an investigation into the correlation between participant-provided adjectives and their corresponding narratives. Finally, this research project will explore the possibility of automatically coding secure base script knowledge in AAI transcripts. By combining technological advances with nuanced human insights, this research project not only provides a pathway toward research studies at scale, but also presents an opportunity to achieve a deeper understanding of emotional and cognitive dimensions within attachment narratives.<br/
Attachment development in children adopted from China: The role of pre-adoption care and sensitive adoptive parenting
Burkholderia multivorans septicemia in a pediatric liver transplant patient
“Cepacia syndrome”, caused by Burkholderia cepacia complex and often associated with cystic fibrosis, carries a high mortality rate. It is rare for Burkholderia multivorans, a species within the B. cepacia complex, to cause cepacia syndrome even among patients with cystic fibrosis. This is the first reported fatal case of cepacia syndrome caused by B. multivorans occurring in a pediatric liver transplant recipient who does not have cystic fibrosis. We describe the unique characteristics of this pathogen among the non–cystic fibrosis population and the importance of early recognition and treatment
Displaying the Heterogeneity of the SN 2002cx-like Subclass of Type Ia Supernovae with Observations of the Pan-STARRS-1 Discovered SN2009ku
SN2009ku, discovered by Pan-STARRS-1, is a Type Ia supernova (SNIa), and a
member of the distinct SN2002cx-like class of SNeIa. Its light curves are
similar to the prototypical SN2002cx, but are slightly broader and have a later
rise to maximum in g. SN2009ku is brighter (~0.6 mag) than other SN2002cx-like
objects, peaking at M_V = -18.4 mag - which is still significantly fainter than
typical SNeIa. SN2009ku, which had an ejecta velocity of ~2000 kms^-1 at 18
days after maximum brightness is spectroscopically most similar to SN2008ha,
which also had extremely low-velocity ejecta. However, SN2008ha had an
exceedingly low luminosity, peaking at M_V = -14.2 mag, ~4 mag fainter than
SN2009ku. The contrast of high luminosity and low ejecta velocity for SN2009ku
is contrary to an emerging trend seen for the SN2002cx class. SN2009ku is a
counter-example of a previously held belief that the class was more homogeneous
than typical SNeIa, indicating that the class has a diverse progenitor
population and/or complicated explosion physics. As the first example of a
member of this class of objects from the new generation of transient surveys,
SN2009ku is an indication of the potential for these surveys to find rare and
interesting objects.Comment: 7 pages, 3 figure
The Structure and Stellar Content of the Outer Disks of Galaxies: A New View from the Pan-STARRS1 Medium Deep Survey
We present the results of an analysis of Pan-STARRS1 Medium Deep Survey multi-band (grizy) images of a sample of 698 low-redshift disk galaxies that span broad ranges in stellar mass, star-formation rate, and bulge/disk ratio. We use population synthesis spectral energy distribution fitting techniques to explore the radial distribution of the light, color, surface mass density, mass/light ratio, and age of the stellar populations. We characterize the structure and stellar content of the galaxy disks out to radii of about twice Petrosian r 90, beyond which the halo light becomes significant. We measure normalized radial profiles for sub-samples of galaxies in three bins each of stellar mass and concentration. We also fit radial profiles to each galaxy. The majority of galaxies have down-bending radial surface brightness profiles in the bluer bands with a break radius at roughly r 90. However, they typically show single unbroken exponentials in the reddest bands and in the stellar surface mass density. We find that the mass/light ratio and stellar age radial profiles have a characteristic "U" shape. There is a good correlation between the amplitude of the down-bend in the surface brightness profile and the rate of the increase in the M/L ratio in the outer disk. As we move from late- to early-type galaxies, the amplitude of the down-bend and the radial gradient in M/L both decrease. Our results imply a combination of stellar radial migration and suppression of recent star formation can account for the stellar populations of the outer disk
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