633 research outputs found
CMZoom III: Spectral Line Data Release
We present an overview and data release of the spectral line component of the
SMA Large Program, \textit{CMZoom}. \textit{CMZoom} observed CO(2-1),
CO(2-1) and CO(2-1), three transitions of HCO, several
transitions of CHOH, two transitions of OCS and single transitions of SiO
and SO, within gas above a column density of N(H)\,cm
in the Central Molecular Zone (CMZ; inner few hundred pc of the Galaxy). We
extract spectra from all compact 1.3\,mm \emph{CMZoom} continuum sources and
fit line profiles to the spectra. We use the fit results from the HCO
3(0,3)-2(0,2) transition to determine the source kinematic properties. We find
\% of the total mass of \emph{CMZoom} sources have reliable
kinematics. Only four compact continuum sources are formally self-gravitating.
The remainder are consistent with being in hydrostatic equilibrium assuming
that they are confined by the high external pressure in the CMZ. Based on the
mass and density of virially bound sources, and assuming star formation occurs
within one free-fall time with a star formation efficiency of , we
place a lower limit on the future embedded star-formation rate of \,M\,yr. We find only two convincing proto-stellar
outflows, ruling out a previously undetected population of very massive,
actively accreting YSOs with strong outflows. Finally, despite having
sufficient sensitivity and resolution to detect high-velocity compact clouds
(HVCCs), which have been claimed as evidence for intermediate mass black holes
interacting with molecular gas clouds, we find no such objects across the large
survey area.Comment: 44 pages, 41 figure
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
Association between variations in the TLR4 gene and incident type 2 diabetes is modified by the ratio of total cholesterol to HDL-cholesterol
<p>Abstract</p> <p>Background</p> <p>Toll-like receptor 4 (TLR4), the signaling receptor for lipopolysaccharides, is an important member of the innate immunity system. Since several studies have suggested that type 2 diabetes might be associated with changes in the innate immune response, we sought to investigate the association between genetic variants in the <it>TLR4 </it>gene and incident type 2 diabetes.</p> <p>Methods</p> <p>A case-cohort study was conducted in initially healthy, middle-aged subjects from the MONICA/KORA Augsburg studies including 498 individuals with incident type 2 diabetes and 1,569 non-cases. Seven SNPs were systematically selected in the <it>TLR4 </it>gene and haplotypes were reconstructed.</p> <p>Results</p> <p>The effect of <it>TLR4 </it>SNPs on incident type 2 diabetes was modified by the ratio of total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C). In men, four out of seven <it>TLR4 </it>variants showed significant interaction with TC/HDL-C after correction for multiple testing (p < 0.01). The influence of the minor alleles of those variants on the incidence of type 2 diabetes was observed particularly for male patients with high values of TC/HDL-C. Consistent with these findings, haplotype-based analyses also revealed that the effect of two haplotypes on incident type 2 diabetes was modified by TC/HDL-C in men (p < 10<sup>-3</sup>). However, none of the investigated variants or haplotypes was associated with type 2 diabetes in main effect models without assessment of effect modifications.</p> <p>Conclusion</p> <p>We conclude that minor alleles of several <it>TLR4 </it>variants, although not directly associated with type 2 diabetes might increase the risk for type 2 diabetes in subjects with high TC/HDL-C. Additionally, our results confirm previous studies reporting sex-related dissimilarities in the development of type 2 diabetes.</p
Study protocol for a non-inferiority trial of cytisine versus nicotine replacement therapy in people motivated to stop smoking
<p>Abstract</p> <p>Background</p> <p>Smokers need effective support to maximise the chances of successful quit attempts. Current smoking cessation medications, such as nicotine replacement therapy (NRT), bupropion, nortriptyline or varenicline, have been shown to be effective in clinical trials but are underused by smokers attempting to quit due to adverse effects, contraindications, low acceptability and/or high cost. Cytisine is a low-cost, plant-based alkaloid that has been sold as a smoking cessation aid in Eastern Europe for 50 years. A systematic review of trial evidence suggests that cytisine has a positive impact on both short- and long-term abstinence rates compared to placebo. However, the quality of the evidence is poor and insufficient for licensing purposes in many Western countries. A large, well-conducted placebo-controlled trial (n = 740) of cytisine for smoking cessation has recently been published and confirms the findings of earlier studies, with 12-month continuous abstinence rates of 8.4% in the cytisine group compared to 2.4% in the placebo group (Relative risk = 3.4, 95% confidence intervals 1.7-7.1). No research has yet been undertaken to determine the effectiveness of cytisine relative to that of NRT.</p> <p>Methods/design</p> <p>A single-blind, randomised controlled, non-inferiority trial has been designed to determine whether cytisine is at least as effective as NRT in assisting smokers to remain abstinent for at least one month. Participants (n = 1,310) will be recruited through the national telephone-based Quitline service in New Zealand and randomised to receive a standard 25-day course of cytisine tablets (Tabex<sup>®</sup>) or usual care (eight weeks of NRT patch and/or gum or lozenge). Participants in both study arms will also receive a behavioural support programme comprising an average of three follow-up telephone calls delivered over an eight-week period by Quitline. The primary outcome is continuous abstinence from smoking at one month, defined as not smoking more than five cigarettes since quit date. Outcome data will also be collected at one week, two months and six months post-quit date.</p> <p>Discussion</p> <p>Cytisine appears to be effective compared with placebo, and given its (current) relative low cost may be an acceptable smoking cessation treatment for smokers, particularly those in low- and middle-income countries. Cytisine's 'natural' product status may also increase its acceptability and use among certain groups of smokers, such as indigenous people, smokers in countries where the use of natural medicines is widespread (e.g. China, India), and in those people who do not want to use NRT or anti-depressants to help them quit smoking. However it is important to ascertain the effectiveness of cytisine compared with that of existing cessation treatments.</p> <p>Trial registration</p> <p>Australian New Zealand Clinical Trials Registry (<a href="http://www.anzctr.org.au/ACTRN12610000590066.aspx">ACTRN12610000590066</a>)</p
T Regulatory Cells Control Susceptibility to Invasive Pneumococcal Pneumonia in Mice
Streptococcus pneumoniae is an important human pathogen responsible for a spectrum of diseases including pneumonia. Immunological and pro-inflammatory processes induced in the lung during pneumococcal infection are well documented, but little is known about the role played by immunoregulatory cells and cytokines in the control of such responses. We demonstrate considerable differences in the immunomodulatory cytokine transforming growth factor (TGF)-β between the pneumococcal pneumonia resistant BALB/c and susceptible CBA/Ca mouse strains. Immunohistochemistry and flow cytometry reveal higher levels of TGF-β protein in BALB/c lungs during pneumococcal pneumonia that correlates with a rapid rise in lung Foxp3+Helios+ T regulatory cells. These cells have protective functions during pneumococcal pneumonia, because blocking their induction with an inhibitor of TGF-β impairs BALB/c resistance to infection and aids bacterial dissemination from lungs. Conversely, adoptive transfer of T regulatory cells to CBA/Ca mice, prior to infection, prolongs survival and decreases bacterial dissemination from lungs to blood. Importantly, strong T regulatory cell responses also correlate with disease-resistance in outbred MF1 mice, confirming the importance of immunoregulatory cells in controlling protective responses to the pneumococcus. This study provides exciting new evidence for the importance of immunomodulation during pulmonary pneumococcal infection and suggests that TGF-β signalling is a potential target for immunotherapy or drug design
Transit Timing Observations from Kepler: IV. Confirmation of 4 Multiple Planet Systems by Simple Physical Models
Eighty planetary systems of two or more planets are known to orbit stars
other than the Sun. For most, the data can be sufficiently explained by
non-interacting Keplerian orbits, so the dynamical interactions of these
systems have not been observed. Here we present 4 sets of lightcurves from the
Kepler spacecraft, which each show multiple planets transiting the same star.
Departure of the timing of these transits from strict periodicity indicates the
planets are perturbing each other: the observed timing variations match the
forcing frequency of the other planet. This confirms that these objects are in
the same system. Next we limit their masses to the planetary regime by
requiring the system remain stable for astronomical timescales. Finally, we
report dynamical fits to the transit times, yielding possible values for the
planets' masses and eccentricities. As the timespan of timing data increases,
dynamical fits may allow detailed constraints on the systems' architectures,
even in cases for which high-precision Doppler follow-up is impractical.Comment: In the proofs process, corrections were made to tables -- most
crucially, the timing data for Kepler-30b and the depths and radii of planets
in Kepler-31 and 3
Kepler Planet-Detection Mission: Introduction and First Results
The Kepler mission was designed to determine the frequency of Earth-sized planets in and near the habitable zone of Sun-like stars. The habitable zone is the region where planetary temperatures are suitable for water to exist on a planet’s surface. During the first 6 weeks of observations, Kepler monitored 156,000 stars, and five new exoplanets with sizes between 0.37 and 1.6 Jupiter radii and orbital periods from 3.2 to 4.9 days were discovered. The density of the Neptune-sized Kepler-4b is similar to that of Neptune and GJ 436b, even though the irradiation level is 800,000 times higher. Kepler-7b is one of the lowest-density planets (~0.17 gram per cubic centimeter) yet detected. Kepler-5b, -6b, and -8b confirm the existence of planets with densities lower than those predicted for gas giant planets
Uniform Atmospheric Retrieval Analysis of Ultracool Dwarfs II : Properties of 11 T-dwarfs
Accepted ApJ. Supplemental material including full posteriors will be included through the link in the published ApJ article © 2017 The American Astronomical Society. All rights reserved.Brown dwarf spectra are rich in information revealing of the chemical and physical processes operating in their atmospheres. We apply a recently developed atmospheric retrieval tool to an ensemble of late T-dwarf (600-800K) near infrared spectra. With these spectra we are able to place direct constraints the molecular abundances of HO, CH, CO, CO, NH, HS, and Na+K, gravity, thermal structure (and effective temperature), photometric radius, and cloud optical depths. We find that ammonia, water, methane, and the alkali metals are present and well constrained in all 11 objects. From the abundance constraints we find no significant trend in the water, methane, or ammonia abundances with temperature, but find a very strong (25) increasing trend in the alkali metal abundances with effective temperature, indicative of alkali rainout. We also find little evidence for optically thick clouds. With the methane and water abundances, we derive the intrinsic atmospheric metallicity and carbon-to-oxygen ratios. We find in our sample, that metallicities are typically sub solar and carbon-to-oxygen ratios are somewhat super solar, different than expectations from the local stellar population. We also find that the retrieved vertical thermal profiles are consistent with radiative equilibrium over the photospheric regions. Finally, we find that our retrieved effective temperatures are lower than previous inferences for some objects and that our radii are larger than expectations from evolutionary models, possibly indicative of un-resolved binaries. This investigation and methodology represents a paradigm in linking spectra to the determination of the fundamental chemical and physical processes governing cool brown dwarf atmospheres.Peer reviewe
Anxiety-like behavior in Rett syndrome: characteristics and assessment by anxiety scales
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