Abstract
The
Hubble Space Telescope
photometric survey of Galactic globular clusters (GCs) has revealed a peculiar “chromosome map” for NGC 6934. In addition to a typical sequence, similar to that ...observed in Type I GCs, NGC 6934 displays additional stars on the red side, analogous to the anomalous Type II GCs, as defined in our previous work. We present a chemical abundance analysis of four red giants in this GC. Two stars are located on the chromosome map sequence common to all GCs, and another two lie on the additional sequence. We find (i) star-to-star Fe variations, with the two anomalous stars being enriched by ∼0.2 dex. Because of our small-size sample, this difference is at the ∼2.5
σ
level. (ii) There is no evidence for variations in the slow neutron-capture abundances over Fe, at odds with what is often observed in anomalous Type II GCs, e.g., M 22 and
ω
Centauri; (iii) no large variations in light elements C, O, and Na, compatible with locations of the targets on the lower part of the chromosome map where such variations are not expected. Since the analyzed stars are homogeneous in light elements, the only way to reproduce the photometric splits on the sub-giant (SGB) and the red giant (RGB) branches is to assume that red RGB/faint SGB stars are enhanced in Fe/H by ∼0.2. This fact corroborates the spectroscopic evidence of a metallicity variation in NGC 6934. The observed chemical pattern resembles only partially the other Type II GCs, suggesting that NGC 6934 might belong either to a third class of GCs, or be a link between normal Type I and anomalous Type II GCs.
ABSTRACT
We present measurements of galaxy clustering from the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III (SDSS‐III). These use the Data Release ...9 (DR9) CMASS sample, which contains 264 283 massive galaxies covering 3275 square degrees with an effective redshift z = 0.57 and redshift range 0.43 < z < 0.7. Assuming a concordance ΛCDM cosmological model, this sample covers an effective volume of 2.2 Gpc3, and represents the largest sample of the Universe ever surveyed at this density, n¯≈3×10−4h−3 Mpc 3. We measure the angle‐averaged galaxy correlation function and power spectrum, including density‐field reconstruction of the baryon acoustic oscillation (BAO) feature. The acoustic features are detected at a significance of 5σ in both the correlation function and power spectrum. Combining with the SDSS‐II luminous red galaxy sample, the detection significance increases to 6.7σ. Fitting for the position of the acoustic features measures the distance to z = 0.57 relative to the sound horizon DV/rs = 13.67 ± 0.22 at z = 0.57. Assuming a fiducial sound horizon of 153.19 Mpc, which matches cosmic microwave background constraints, this corresponds to a distance DV (z = 0.57) = 2094 ± 34 Mpc. At 1.7 per cent, this is the most precise distance constraint ever obtained from a galaxy survey. We place this result alongside previous BAO measurements in a cosmological distance ladder and find excellent agreement with the current supernova measurements. We use these distance measurements to constrain various cosmological models, finding continuing support for a flat Universe with a cosmological constant.
Objectives
The aim of the present study was to investigate whether late-life depression (LLD) is associated with incident frailty over time.
Design
Prospective cohort study, one-year follow-up.
...Setting
Geriatric outpatient clinic, Southwestern of Brazil.
Participants
181 follow-up participants aged 60 years or over.
Measurements
Depressive disorders were classified as Major Depressive disorder (MDD) or Subthreshold Depression (STD) according to DSM-5 criteria. Depressive symptoms were assessed with validated versions of 15-item Geriatric Depression Scale (GDS-15) and 9-item Patient Health Questionnaire (PHQ-9). We performed binary logistic regressions to estimate the odds ratio (OR) for frailty in LLD adjusting for multiple confounders. Participants who were frail at baseline were excluded from the analyses according to measures of frailty (FRAIL questionnaire and 36-item Frailty Index, FI-36). We also estimated the risk ratio or relative risk (RR) and the risk difference (RD) for incident frailty.
Results
We observed a 2 to 4-fold increased risk for incident frailty among participants with LLD. The presence of a depressive disorder was significantly associated with the onset of frailty (adjusted OR for FRAIL and FI-36: 3.07 95% CI = 1.03–9.17 and 3.76 95% CI = 1.09–12.97, respectively. Notably, the risk for frailty due to LLD was significantly higher with the FI-36 compared to the FRAIL (RR: 3.03 versus 2.23). RD was of 17.3% and 12.7% with the FRAIL and the FI-36, respectively.
Conclusion
Our data support the association between LLD and incident frailty over one year among geriatric outpatients, reinforcing longitudinal evidence from population-based studies.
The aim of this study was to characterize the alveolar bone of edentulous maxillary sites using texture analysis (TA) of cone beam computed tomography (CBCT) images and to correlate the results to ...the insertion torque, thus verifying whether TA is a predictive tool of final implant treatment. This study was conducted on patients who had received single implants in the maxilla (46 implants) 1year earlier and whose torque values were properly recorded. Three cross-sections of the sites were selected on CBCT scans. Two regions of interest (ROIs) corresponding to the implant bone site and peri-implant bone were also outlined, according to virtual planning. The CBCT scans were exported to MaZda software, where the two ROIs were delimited following the previously demarcated contours. Values for the co-occurrence matrix were calculated for TA. With regard to the insertion torque value, there was a direct correlation with the contrast of the peri-implant bone (P<0.001) and an inverse correlation with the entropy of the implant bone site (P=0.006). A greater contrast indicates a greater torque value for insertion of the implants, and there is a possible association with a lower entropy value of the implant–bone interface.
Visceral leishmaniosis is a neglected tropical disease. We evaluated the spatial distribution of cases of visceral leishmaniosis in the state of Alagoas, Brazil. All cases of VL, registered by the ...health department, were analyzed and georeferenced. Results: Between 2008 and 2017, 97.1% of the municipalities presented sporadic classification of transmission. With temporal evolution, the incidence of cases of visceral leishmaniosis was concentrated in most municipalities in the microregion of Santana do Ipanema-AL. Space-time analysis, if considered, may promote the improvement of surveillance and control actions of visceral leishmaniosis.
Heart disease is a major cause of death worldwide. Chronic Chagas cardiomyopathy (CCC) caused by infection with Trypanosoma cruzi leading to high mortality in adults, and rheumatic heart disease ...(RHD), resulting from infection by Streptococcus pyogenes affecting mainly children and young adults, are amongst the deadliest heart diseases in low-middle income countries. Despite distinct etiology, the pathology associated with both diseases is a consequence of inflammation. Here we compare systemic immune profile in patients with these cardiopathies, to identify particular and common characteristics in these infectious heart diseases. We evaluated the expression of 27 soluble factors, employing single and multivariate analysis combined with machine-learning approaches. We observed that, while RHD and CCC display higher levels of circulating mediators than healthy individuals, CCC is associated with stronger immune activation as compared to RHD. Despite distinct etiologies, univariate analysis showed that expression of TNF, IL-17, IFN-gamma, IL-4, CCL4, CCL3, CXCL8, CCL11, CCL2, PDGF-BB were similar between CCC and RHD, consistent with their inflammatory nature. Network analysis revealed common inflammatory pathways between CCC and RHD, while highlighting the broader reach of the inflammatory response in CCC. The final multivariate model showed a 100% discrimination power for the combination of the cytokines IL-12p70, IL-1Ra, IL-4, and IL-7 between CCC and RHD groups. Thus, while clear immunological distinctions were identified between CCC and RHD, similarities indicate shared inflammatory pathways in these infectious heart diseases. These results contribute to understanding the pathogenesis of CCC and RHD and may impact the design of immune-based therapies for these and other inflammatory cardiopathies that may also share immunological characteristics.
We investigate the effects of potential sources of systematic error on the angular and photometric redshift, z
phot, distributions of a sample of redshift 0.4 < z < 0.7 massive galaxies whose ...selection matches that of the Baryon Oscillation Spectroscopic Survey (BOSS) constant-mass sample. Utilizing over 112 778 BOSS spectra as a training sample, we produce a photometric redshift catalogue for the galaxies in the Sloan Digital Sky Survey eight data release imaging area that, after masking, covers nearly one quarter of the sky (9913 deg2). We investigate fluctuations in the number density of objects in this sample as a function of Galactic extinction, seeing, stellar density, sky background, airmass, photometric offset and North/South Galactic hemisphere. We find that the presence of stars of comparable magnitudes to our galaxies (which are not traditionally masked) effectively removes area. Failing to correct for such stars can produce systematic errors on the measured angular autocorrelation function, w(θ), that are larger than its statistical uncertainty. We describe how one can effectively mask for the presence of the stars, without removing any galaxies from the sample, and minimize the systematic error. Additionally, we apply two separate methods that can be used to correct for the systematic errors imparted by any parameter that can be turned into a map on the sky. We find that failing to properly account for varying sky background introduces a systematic error on w(θ). We measure w(θ), in four z
phot slices of width 0.05 between 0.45 < z
phot < 0.65, and find that the measurements, after correcting for the systematic effects of stars and sky background, are generally consistent with a generic Λ cold dark matter model, at scales up to 60°. At scales greater than 3° and z
phot > 0.5, the magnitude of the corrections we apply is greater than the statistical uncertainty in w(θ). The photometric redshift catalogue we produce will be made publicly available at http://portal.nersc.gov/project/boss/galaxy/photoz/.
Chronic Hepatitis B (HB) is the main risk factor for chronic liver disease (CLD) and hepatocellular carcinoma (HCC) in many low‐resource countries, where diagnosis is constrained by lack of clinical, ...histopathological and biomarker resources. We have used proteomics to detect plasma biomarkers that outperform α‐Fetoprotein (AFP), the most widely used biomarker for HCC diagnosis in low‐resource contexts. Deep‐plasma proteome analysis was performed in HCC patients, patients with CLD and in HB‐carrier controls from Thailand (South‐East Asia) and The Gambia (West‐Africa). Mass spectrometry profiling identified latent‐transforming growth factor β binding‐protein 2 (LTBP2) and Osteopontin (OPN) as being significantly elevated in HCC versus CLD and controls. These two proteins were further analyzed by ELISA in a total of 684 plasma samples, including 183 HCC, 274 CLD and 227 asymptomatic controls. When combined, LTBP2 and OPN showed an area under the receiver operating curve of 0.85 in distinguishing HCC from CLD in subjects with AFP <20 ng/mL. In a prospective cohort of 115 CLD patients from Korea, increased plasma levels of LTBP2 and/or OPN were detected in plasma collected over 2 years prior to diagnosis in 21 subjects who developed HCC. Thus, the combination of LTBP2 and OPN outperformed AFP for diagnosis and prediction of HCC and may therefore improve biomarker‐based detection of HBV‐related HCC.
What's new?
Chronic infection with hepatitis B virus (HBV) is the main risk factor for chronic liver disease and hepatocellular carcinoma (HCC) in many low‐resource countries, where diagnosis is constrained by lack of clinical, histopathological, and biomarker resources. Here, deep‐plasma proteomics was used to identify candidate biomarkers for HCC diagnosis. Validation studies on a total of 684 samples showed that elevated levels of LTBP2 and/or OPN are highly specific and sensitive markers for distinguishing HCC from chronic liver disease. LTBP2 appears highly associated with HBV‐related HCC, while OPN shows a robust and consistent association with HCC in both HBV and HCV contexts.
We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event ...in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 ± 0.001 based on the host-galaxy emission lines) and likely spectral type (Type I). Using this redshift, we find
$M^{\rm peak}_U=-21.05^{+0.10}_{-0.09}$
for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low-metallicity (sub-solar), low stellar-mass host galaxy (log (M/M⊙) = 9.3 ± 0.3), consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to 14 similarly well-observed SLSNe-I in the literature and find that it possesses one of the slowest declining tails (beyond +30 d rest-frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.2–0.3 mag between +25 and +30 d after peak (rest frame) depending on redshift range studied; this could be important for ‘standardizing’ such supernovae, as is done with the more common Type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I – the radioactive decay of 56Ni, and a magnetar – and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 d in the rest frame of the supernova.
Graphene layers were synthesized on silica and 90, 300, 400 and 700 nm thick silicon dioxide films by chemical vapor deposition at semi-atmospheric pressure environment, using controlled mixtures of ...hydrogen, argon and methane gases. The effects of the methane flux and the total pressure on the homogeneity of the graphene layers were investigated. The samples were characterized by Raman spectroscopy and mapping, X-ray photoelectron spectroscopy and optical transmittance measurements. The latter method was used to determine the number of graphene layers of the samples. Scanning electron microscopy, atomic force microscopy was carried out to study the surface uniformity and electrical measurements were also performed. Our results indicate that large area, a homogeneous nanocrystalline graphene layer can be obtained with an appropriate choice of synthesis parameters. Raman spectroscopy results indicate turbostratic graphene bilayers were obtained.
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•Bilayer graphene was synthetized on SiO2 substrates without metallic catalysts•Raman spectroscopy results indicated that bilayer graphene is turbostratic.•The quality of graphene is directly related to growth pressure and precursor flux
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