ABSTRACT We present an analysis of the CN and CH molecular band strengths in NGC 6791 from low-resolution Sloan Extension for Galactic Understanding and Exploration spectra as a means to detect ...chemical variations in the cluster. NGC 6791 is a heavily studied open cluster (OC) due to its unique combination of old age, high mass, and high metallicity. These characteristics place NGC 6791 between the physical properties of most globular and OCs. Recent photometric and spectroscopic studies yield contradicting results, with some claiming to detect signs of multiple populations, as in globular clusters, while others do not. We do not find large spreads in the CN and CH band strength distributions that would suggest multiple populations. By pairing spectral synthesis with the measured CN values, we conclude that the maximum N/Fe variation in the cluster is 0.2 dex. Additionally, we find that the saturation of the CH band at high metallicities limits its usefulness in detecting multiple populations and determining C abundances.
•Pain consistent with cerebrovascular FMD was related to lower quality of life.•Those with abdominal pain reported higher anxiety and depression.•Migraine headache was associated with lower ...self-rated health.•Over 80% of respondents had cerebrovascular FMD and many live with pain.•Patients with FMD should be assessed for pain and mental health needs.
Fibromuscular dysplasia (FMD), a nonatherosclerotic arterial disease, can cause pain and vascular complications. The aim of this study was to examine the impact of FMD symptoms and complications on quality of life, depression, anxiety, and self-rated health.
This was a cross-sectional, correlational study.
Participants were adults with a diagnosis of FMD. Quality of life (36-Item Short Form Health Survey), anxiety and depression (Patient-Reported Outcomes Measurement Information System PROMIS®), self-rated health question, and symptom/complication questionnaires were mailed to patients with FMD. Scores were compared with symptoms and complications. Multivariable linear models were fit for symptoms and survey scores. Ordinal regression was used for self-rated health. Backwards selection was run for each model. Alpha of 0.05 and 95% confidence intervals were used.
Of the 162 (275 total; 47.8%) patients who returned surveys (156 female), 130 had carotid or vertebral artery involvement (80.2%). Migraine (p < .001), neck pain (p = .036), and flank pain (p = .025) were associated with decrease in Mental Component scores. Migraine (p = .002) and neck pain (p = .023) were associated with lower Physical Component scores. Patients reporting abdominal pain compared with those without had 4.88 points higher depression. Abdominal pain (p = .031) and pulsatile tinnitus (p = .011) were associated with greater anxiety. Migraine was associated with (p = .002) lower self-rated health. Participants with history of stroke/transient ischemic attack had 2.42 (1.08, 5.46; p = .033) times the odds of poor self-rated health compared with those without stroke/transient ischemic attack.
Among patients with FMD, presence of pain and history of vascular complications were related to lower quality of life and self-rated health.
We report the search for intracluster light in four Abell type II-III (non- cD) galaxy clusters: A801, A1234, A1553, and A1914. We find that on average these clusters contain approx10% of their ...detected stellar luminosity in a diffuse component. We show that for two of the clusters the intracluster light closely follows the galaxy distribution, but in the other two cases, there are noticeable differences between the spatial distribution of the galaxies and the intracluster light. We report the results of a search for intracluster tidal debris in each cluster and note that A1914 in particular has a number of strong tidal features likely due to its status as a recent cluster merger. One of the A1914 features appears to be spatially coincident with an extension seen in weak lensing maps, implying that the feature traces a large amount of mass. We compare these results with numerical simulations of hierarchically formed galaxy clusters and find good general agreement between the observed and simulated images, although we also find that our observations sample only the brightest features of the intracluster light. Together, these results suggest that intracluster light can be a valuable tool in determining the evolutionary state of galaxy clusters.
We have measured the amount of kinematic substructure in the Galactic halo using the final data set from the Spaghetti project, a pencil-beam high-latitude sky survey. Our sample contains 101 ...photometrically selected and spectroscopically confirmed giants with accurate distance, radial velocity, and metallicity information. We have developed a new clustering estimator: the '4distance' measure, which when applied to our data set leads to the identification of one group and seven pairs of clumped stars. The group, with six members, can confidently be matched to tidal debris of the Sagittarius dwarf galaxy. Two pairs match the properties of known Virgo structures. Using models of the disruption of Sagittarius in Galactic potentials with different degrees of dark halo flattening, we show that this favors a spherical or prolate halo shape, as demonstrated by Newberg et al. using the Sloan Digital Sky Survey data. One additional pair can be linked to older Sagittarius debris. We find that 20% of the stars in the Spaghetti data set are in substructures. From comparison with random data sets, we derive a very conservative lower limit of 10% to the amount of substructure in the halo. However, comparison to numerical simulations shows that our results are also consistent with a halo entirely built up from disrupted satellites, provided that the dominating features are relatively broad due to early merging or relatively heavy progenitor satellites.
Using a sample of 246 metal-poor stars (RR Lyraes, red giants, and red horizontal branch stars) which is remarkable for the accuracy of its six-dimensional kinematical data, we find, by examining the ...distribution of stellar orbital angular momenta, a new component for the local halo which has an axial ratio c/a ~ 0.2, a similar flattening to the thick disk. It has a small prograde rotation but is supported by velocity anisotropy, and contains more intermediate-metallicity stars (with -1.5 < Fe/H < -1.0) than the rest of our sample. We suggest that this component was formed quite late, during or after the formation of the disk. It formed either from the gas that was accreted by the last major mergers experienced by the Galaxy, or by dynamical friction of massive infalling satellite(s) with the halo and possibly the stellar disk or thick disk. The remainder of the halo stars in our sample, which are less closely confined to the disk plane, exhibit a clumpy distribution in energy and angular momentum, suggesting that the early, chaotic conditions under which the inner halo formed were not violent enough to erase the record of their origins. The clumpy structure suggests that a relatively small number of progenitors were responsible for building up the inner halo, in line with theoretical expectations. We find a difference in mean binding energy between the RR Lyrae variables and the red giants in our sample, suggesting that more of the RR Lyraes in the sample belong to the outer halo, and that the outer halo may be somewhat younger, as first suggested by Searle & Zinn. We also find that the RR Lyrae mean rotation is more negative than the red giants, which is consistent with the recent result of Carollo et al. that the outer halo has a retrograde rotation and with the difference in kinematics seen between RR Lyraes and blue horizontal branch stars by Kinman et al. (2007).
ABSTRACT We present griz observations for the clusters M92, M13 and NGC 6791 and gr photometry for M71, Be 29 and NGC 7789. In addition we present new membership identifications for all these ...clusters, which have been observed spectroscopically as calibrators for the Sloan Digital Sky Survey (SDSS)/SEGUE survey; this paper focuses in particular on the red giant branch stars in the clusters. In a number of cases, these giants were too bright to be observed in the normal SDSS survey operations, and we describe the procedure used to obtain spectra for these stars. For M71, we also present a new variable reddening map and a new fiducial for the gr giant branch. For NGC 7789, we derived a transformation from Teff to g-r for giants of near solar abundance, using IRFM Teff measures of stars with good ugriz and 2MASS photometry and SEGUE spectra. The result of our analysis is a robust list of known cluster members with correctly dereddened and (if needed) transformed gr photometry for crucial calibration efforts for SDSS and SEGUE.
We study the eccentricity distribution of a thick-disc sample of stars (defined as those with Vy
> 50 km s−1 and 1 < |z|/kpc < 3) observed in the Radial Velocity Experiment (RAVE). We compare this ...distribution with those obtained in four simulations of galaxy formation taken from the literature as compiled by Sales et al. Each simulation emphasizes different scenarios for the origin of such stars (satellite accretion, heating of a pre-existing thin disc during a merger, radial migration, and gas-rich mergers). We find that the observed distribution peaks at low eccentricities and falls off smoothly and rather steeply to high eccentricities. This finding is fairly robust to changes in distances and to plausible assumptions about thin-disc contamination. Our results favour models where the majority of stars formed in the Galaxy itself on orbits of modest eccentricity and disfavour the pure satellite accretion case. A gas-rich merger origin where most of the stars form 'in situ' appears to be the most consistent with our data.
The effects of raised brain lactate levels on neuronal survival following hypoxia or ischemia is still a source of controversy among basic and clinical scientists. We have sought to address this ...controversy by studying the effects of glucose and lactate on neuronal survival in acute and cultured hippocampal slices. Following a 1‐h hypoxic episode, neuronal survival in cultured hippocampal slices was significantly higher if glucose was present in the medium compared with lactate. However, when the energy substrate during the hypoxic period was glucose and then switched to lactate during the normoxic recovery period, the level of cell damage in the CA1 region of organotypic cultures was significantly improved from 64.3 ± 2.1 to 74.6 ± 2.1% compared with cultures receiving glucose during and after hypoxia. Extracellular field potentials recorded from the CA1 region of acute slices were abolished during oxygen deprivation for 20 min, but recovered almost fully to baseline levels with either glucose (82.6 ± 10.0%) or lactate present in the reperfusion medium (108.1 ± 8.3%). These results suggest that lactate alone cannot support neuronal survival during oxygen deprivation, but a combination of glucose followed by lactate provides for better neuroprotection than either substrate alone.
Premature chromosome condensation (PCC) is a consequence of early mitotic entry, where mitosis begins before completion of DNA replication. Previously we have identified mutations in MCPH1, a DNA ...damage response and potential tumor suppressor gene, as a cause of primary microcephaly and PCC. Here we describe a high-throughput assay to identify modifiers of PCC. Reverse transfection of control siRNA followed by a forward transfection of MCPH1 small interfering RNA (siRNA) was performed to induce PCC. Condensin II subunits CAPG2 and CAPH2 were validated as PCC modifiers and therefore positive controls. Cell nuclei were detected by DAPI staining using an Operetta imaging system. PCC and nuclei number were determined using Columbus analysis software. Two batches of nine plates were used to determine assay efficacy. Each plate contained four negative (nontargeting) and eight positive control siRNAs. Mean % PCC was 12.35% (n = 72) for negative controls and 4.25% (n = 144) for positive controls. Overall false-positive and false-negative rates were 0% (n = 72) and 2.1% (n = 144), respectively. This assay is currently being used to screen a human druggable genome siRNA library to identify novel therapeutic targets for cancer treatment. The assay can also be used to identify novel compounds and genes that induce PCC.
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