86 research outputs found
Are radio galaxies and quiescent galaxies different? Results from the analysis of HST brightness profiles
We present a study of the optical brightness profiles of early type galaxies,
using a number of samples of radio galaxies and optically selected elliptical
galaxies. For the radio galaxy samples--B2 of Fanaroff-Riley type I and 3C of
Fanaroff-Riley type II-- we determined a number of parameters that describe a
"Nuker-law" profile, which were compared with those already known for the
optically selected objects. We find that radio active galaxies are always of
the "core" type (i.e. an inner Nuker law slope gamma < 0.3). However, there are
core-type galaxies which harbor no significant radio source and which are
indistinguishable from the radio active galaxies. We do not find any radio
detected galaxy with a power law profile (gamma > 0.5). This difference is not
due to any effect with absolute magnitude, since in a region of overlap in
magnitude the dichotomy between radio active and radio quiescent galaxies
remains. We speculate that core-type objects represent the galaxies that have
been, are, or may become, radio active at some stage in their lives; active and
non-active core-type galaxies are therefore identical in all respects except
their eventual radio-activity: on HST scales we do not find any relationship
between boxiness and radio-activity. There is a fundamental plane, defined by
the parameters of the core (break radius r_b and break brightness mu_b), which
is seen in the strong correlation between r_b and mu_b. The break radius is
also linearly proportional to the optical Luminosity in the band. Moreover,
for the few galaxies with an independently measured black hole mass, the break
radius turns out to be tightly correlated with M_{BH}. The black hole mass
correlates even better with the combination of fundamental plane parameters r_b
and mu_b, which represents the central velocity dispersion.Comment: Accepted for publication in A&A, 20 Pages, 9 figure
GALEX Ultraviolet Photometry of Globular Clusters in M31
We present ultraviolet photometry for globular clusters (GCs) in M31 from 15
square deg of imaging using the Galaxy Evolution Explorer (GALEX). We detect
200 and 94 GCs with certainty in the near-ultraviolet (NUV; 1750 - 2750
Angstroms) and far-ultraviolet (FUV; 1350 - 1750 Angstroms) bandpasses,
respectively. Our rate of detection is about 50% in the NUV and 23% in the FUV,
to an approximate limiting V magnitude of 19. Out of six clusters with
[Fe/H]>-1 seen in the NUV, none is detected in the FUV bandpass. Furthermore,
we find no candidate metal-rich clusters with significant FUV flux, because of
the contribution of blue horizontal-branch (HB) stars, such as NGC 6388 and NGC
6441, which are metal-rich Galactic GCs with hot HB stars. We show that our
GALEX photometry follows the general color trends established in previous UV
studies of GCs in M31 and the Galaxy. Comparing our data with Galactic GCs in
the UV and with population synthesis models, we suggest that the age range of
M31 and Galactic halo GCs are similar.Comment: This paper will be published as part of the Galaxy Evolution Explorer
(GALEX) Astrophysical Journal Letters Special Issue. Links to the full set of
papers will be available at http://www.galex.caltech.edu/PUBLICATIONS/ after
November 22, 200
Raman Scattered He II Line in the Planetary Nebula M2-9 and the Symbiotic Stars RR Telescopii and He 2-106
In this Letter, we report the detection of an emission feature around 6545
\AA in the spectra of the bipolar planetary nebula M2-9 and the symbiotic stars
RR Telescopii and He 2-106 and propose to identify it as the He II Raman
scattered feature. This feature was predicted by Nussbaumer, Schmid & Vogel
(1989), who suggested that it is formed through Raman scattering by atomic
hydrogen of He II photons with slightly shorter wavelength than
that of Ly. The scattering cross section for
this process implies the existence of a neutral hydrogen component with a
column density around the He II emission
regions in these objects, which are believed to be associated with the mass
loss process in the late stage of stellar evolution. Brief discussions on the
astrophysical implications of Raman scattering in these objects are presented.Comment: 8 pages, 2 figures, accepted for publication in the Astrophysical
Journal Letter
Fatty Acid Binding Protein 1 Is Related with Development of Aspirin-Exacerbated Respiratory Disease
BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) refers to the development of bronchoconstriction in asthmatics following the ingestion of aspirin. Although alterations in eicosanoid metabolites play a role in AERD, other immune or inflammatory mechanisms may be involved. We aimed to identify proteins that were differentially expressed in nasal polyps between patients with AERD and aspirin-tolerant asthma (ATA). METHODOLOGY/PRINCIPAL FINDINGS: Two-dimensional electrophoresis was adopted for differential display proteomics. Proteins were identified by liquid chromatography-tandem mass spectrometry (LC-MS). Western blotting and immunohistochemical staining were performed to compare the amount of fatty acid-binding protein 1 (FABP1) in the nasal polyps of patients with AERD and ATA. Fifteen proteins were significantly up- (seven spots) or down-regulated in the nasal polyps of patients with AERD (n = 5) compared to those with ATA (n = 8). LC-MS revealed an increase in seven proteins expression and a decrease in eight proteins expression in patients with AERD compared to those with ATA (P = 0.003-0.045). FABP1-expression based on immunoblotting and immunohistochemical analysis was significantly higher in the nasal polyps of patients with AERD compared to that in patients with ATA. FABP1 was observed in epithelial, eosinophils, macrophages, and the smooth-muscle cells of blood vessels in the polyps. CONCLUSIONS/SIGNIFICANCE: Our results indicate that alterations in 15 proteins, including FABP1, may be related to the development of AERD
Capillary electrophoresis mass spectrometry-based saliva metabolomics identified oral, breast and pancreatic cancer-specific profiles
Saliva is a readily accessible and informative biofluid, making it ideal for the early detection of a wide range of diseases including cardiovascular, renal, and autoimmune diseases, viral and bacterial infections and, importantly, cancers. Saliva-based diagnostics, particularly those based on metabolomics technology, are emerging and offer a promising clinical strategy, characterizing the association between salivary analytes and a particular disease. Here, we conducted a comprehensive metabolite analysis of saliva samples obtained from 215 individuals (69 oral, 18 pancreatic and 30 breast cancer patients, 11 periodontal disease patients and 87 healthy controls) using capillary electrophoresis time-of-flight mass spectrometry (CE-TOF-MS). We identified 57 principal metabolites that can be used to accurately predict the probability of being affected by each individual disease. Although small but significant correlations were found between the known patient characteristics and the quantified metabolites, the profiles manifested relatively higher concentrations of most of the metabolites detected in all three cancers in comparison with those in people with periodontal disease and control subjects. This suggests that cancer-specific signatures are embedded in saliva metabolites. Multiple logistic regression models yielded high area under the receiver-operating characteristic curves (AUCs) to discriminate healthy controls from each disease. The AUCs were 0.865 for oral cancer, 0.973 for breast cancer, 0.993 for pancreatic cancer, and 0.969 for periodontal diseases. The accuracy of the models was also high, with cross-validation AUCs of 0.810, 0.881, 0.994, and 0.954, respectively. Quantitative information for these 57 metabolites and their combinations enable us to predict disease susceptibility. These metabolites are promising biomarkers for medical screening
Orthostatic intolerance symptoms are associated with depression and diminished quality of life in patients with postural tachycardia syndrome
The AgMIP Coordinated Climate-Crop Modeling Project (C3MP): Methods and Protocols
Climate change is expected to alter a multitude of factors important to agricultural
systems, including pests, diseases, weeds, extreme climate events, water resources,
soil degradation, and socio-economic pressures. Changes to carbon dioxide concentration
([CO2]), temperature, andwater (CTW) will be the primary drivers of change
in crop growth and agricultural systems. Therefore, establishing the CTW-change
sensitivity of crop yields is an urgent research need and warrants diverse methods
of investigation. Crop models provide a biophysical, process-based tool to investigate crop
responses across varying environmental conditions and farm management techniques,
and have been applied in climate impact assessment by using a variety of
methods (White et al., 2011, and references therein). However, there is a significant
amount of divergence between various crop models’ responses to CTW changes
(R¨otter et al., 2011). While the application of a site-based crop model is relatively
simple, the coordination of such agricultural impact assessments on larger scales
requires consistent and timely contributions from a large number of crop modelers,
each time a new global climate model (GCM) scenario or downscaling technique
is created. A coordinated, global effort to rapidly examine CTW sensitivity across
multiple crops, crop models, and sites is needed to aid model development and
enhance the assessment of climate impacts (Deser et al., 2012)..
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