We present initial results from a time series BVI survey of two fields in NGC 4258 using the HST ACS. This galaxy was selected because of its accurate maser-based distance, which is anticipated to ...have a total uncertainty of 63%. The goal of the HST observations is to provide an absolute calibration of the Cepheid distance scale and to measure its dependence on chemical abundance (the so-called metallicity effect). We carried out observations of two fields at different galactocentric distances with a mean abundance difference of 0.5 dex. We discovered a total of 281 Cepheids with periods ranging from 4 to 45 days (the duration of our observing window). We determine a Cepheid distance modulus for NGC 4258 (relative to the LMC) of mu sub(0) = 10.88 c 0.04 (random) c 0.05 (systematic) mag. Given the published maser distance to the galaxy, this implies k sub(0)(LMC) = 18.41 c 0.10 sub(r) c 0.13 sub(s) mag or D(LMC) = 48.1 c 2.3 sub(r) c 2.9 sub(s) kpc. We measure a metallicity effect of g = -0.29 c 0.09 sub(r) c 0.05 sub(s) mag dex super(-1). We see no evidence for a variation in the slope of the period-luminosity relation as a function of abundance. We estimate a Hubble constant of H sub(0) = 74 c 3 sub(r) c 6 sub(s) km s super(-1) Mpc super(-1) using a recent sample of four well-observed Type Ia SNe and our new calibration of the Cepheid distance scale. It may soon be possible to measure the value of H sub(0) with a total uncertainty of 5%, with consequent improvement in the determination of the equation of state of dark energy.
Abstract
We derive a distance of 15.8 ± 0.4 Mpc to the archetypal Seyfert 1 galaxy NGC 4151 based on the near-infrared Cepheid period–luminosity relation and new Hubble Space Telescope multiband ...imaging. This distance determination, based on measurements of 35 long-period (
P
> 25 days) Cepheids, will support the absolute calibration of the supermassive black hole mass in this system, as well as studies of the dynamics of the feedback or feeding of its active galactic nucleus.
ABSTRACT
We present the galaxy group catalogue for the recently completed 2MASS Redshift Survey (2MRS; Macri et al. 2019) which consists of 44 572 redshifts, including 1041 new measurements for ...galaxies mostly located within the Zone of Avoidance. The galaxy group catalogue is generated by using a novel, graph-theory based, modified version of the friends-of-friends algorithm. Several graph-theory examples are presented throughout this paper, including a new method for identifying substructures within groups. The results and graph-theory methods have been thoroughly interrogated against previous 2MRS group catalogues and a Theoretical Astrophysical Observatory (TAO) mock by making use of cutting-edge visualization techniques including immersive facilities, a digital planetarium, and virtual reality. This has resulted in a stable and robust catalogue with on-sky positions and line-of-sight distances within 0.5 and 2 Mpc, respectively, and has recovered all major groups and clusters. The final catalogue consists of 3022 groups, resulting in the most complete ‘whole-sky’ galaxy group catalogue to date. We determine the 3D positions of these groups, as well as their luminosity and comoving distances, observed and corrected number of members, richness metric, velocity dispersion, and estimates of R200 and M200. We present three additional data products, i.e. the 2MRS galaxies found in groups, a catalogue of subgroups, and a catalogue of 687 new group candidates with no counterparts in previous 2MRS-based analyses.
To determine the sex-specific relation of frontal plane alignment (FPA) to magnetic resonance imaging (MRI)-defined features of patellofemoral osteoarthritis, and also to tibiofemoral osteoarthritis ...and knee pain.
The Multicenter Osteoarthritis Study is cohort study comprised of individuals with or at risk of knee osteoarthritis. We determined the sex-specific dose–response relation of baseline FPA to MRI-defined patellofemoral and tibiofemoral structural worsening, and incident knee pain, over 7 years.
In women only, greater varus alignment was associated with medial patellofemoral osteophytes (risk ratio RR 1.7 95% CI 1.2, 2.6) and valgus with lateral patellofemoral osteophytes (RR 1.9 1.0, 3.6). In men, greater varus increased risk for medial tibiofemoral cartilage worsening (RR 1.7 1.1, 2.6), and valgus for lateral tibiofemoral cartilage worsening (RR 1.8 1.6, 2.2). In women, findings were similar for tibiofemoral cartilage, but varus also increased risk for medial bone marrow lesions BMLs (RR 2.2 1.6, 3.1) and medial osteophytes (RR 1.8 1.3, 2.5), and valgus for lateral BMLs (RR 3.3 2.2, 4.5) and osteophytes (RR 2.0 1.2, 3.2). Varus increased risk of incident pain in men (RR 1.7 1.4, 2.2) and women (RR 1.3 1.0, 1.6), valgus did so in men only (RR 1.5 1.1, 1.9).
FPA was associated with patellofemoral osteophyte worsening in women, though overall was more strongly associated with tibiofemoral than patellofemoral osteoarthritis feature worsening. FPA in women was more consistently associated with structural worsening, yet men had higher associations with incident pain.
Abstract
We derive a distance of
D
= 16.6 ± 0.3 Mpc (
μ
= 31.10 ± 0.04 mag) to the archetypal narrow-line Seyfert 1 galaxy NGC 4051 based on Cepheid period–luminosity relations and new Hubble Space ...Telescope multiband imaging. We identify 419 Cepheid candidates and estimate the distance at both optical and near-infrared wavelengths using subsamples of precisely photometered variables (123 and 47 in the optical and near-infrared subsamples, respectively). We compare our independent photometric procedures and distance-estimation methods to those used by the Supernovae, H0, for the Equation of State team and find agreement to 0.01 mag. The distance we obtain suggests an Eddington ratio of
for NGC 4051, typical of narrow-line Seyfert 1 galaxies, unlike the seemingly odd value implied by previous distance estimates. We derive a peculiar velocity of −490 ± 34 km s
−1
for NGC 4051, consistent with the overall motion of the Ursa Major Cluster in which it resides. We also revisit the energetics of the NGC 4051 nucleus, including its outflow and mass accretion rates.
We present UBVRIJHK photometry and optical spectroscopy of the so-called peculiar Type Ia supernova 1999by in NGC 2841. The observations began 1 week before visual maximum light, which is well ...defined by daily observations. The light curves and spectra are similar to those of the prototypical subluminous event SN 1991bg. We find that maximum light in B occurred on 1999 May 10.3 UT (JD 2,451,308.8 plus or minus 0.3) with B = 13.66 plus or minus 0.02 and a color of B sub(max) - V sub(max) = 0.51 plus or minus 0.03. The late-time color implies minimal dust extinction from the host galaxy. Our photometry, when combined with the recent Cepheid distance to NGC 2841, gives a peak absolute magnitude of M sub(B) = -17.15 plus or minus 0.23, making SN 1999by one of the least luminous Type Ia events ever observed. We estimate a decline rate parameter of Delta m sub(15)(B) = 1.90 mag, versus 1.93 for SN 1991bg, for which 1.10 is typical for so-called normal events. We compare SN 1999by with other subluminous events and find that the B sub(max) - V sub(max) color correlates strongly with the decline rate and may be a more sensitive indicator of luminosity than the fading rate for these objects. We find a good correlation between luminosity and the depth of the spectral feature at 580 nm, which had been attributed solely to Si II. We show that in cooler photospheres the 580 nm feature is dominated by Ti II, which provides a simple physical explanation for the correlation. Using only subluminous Type Ia supernovae, we derive a Hubble parameter of H sub(0) = 75 super(+) sub(-) super(1) sub(1) super(2) sub(1) km s super(-1) Mpc super(-1), consistent with values found from brighter events.
We identify and phase a sample of 81 Cepheids in the maser-host galaxy NGC 4258 using the Large Binocular Telescope, and obtain calibrated mean magnitudes in up to four filters for a subset of 43 ...Cepheids using archival Hubble Space Telescope data. We employ three models to study the systematic effects of extinction, the assumed extinction law, and metallicity on the Cepheid distance to NGC 4258. We find a correction to the Cepheid colours consistent with a greyer extinction law in NGC 4258 compared to the Milky Way (R
V
=
$4.9_{-0.7}^{+0.9}$
), although we believe this is indicative of other systematic effects. If we combine our Cepheid sample with previously known Cepheids, we find a significant metallicity adjustment to the distance modulus of γ1 = −0.61 ± 0.21 mag dex−1 for the Zaritsky et al. metallicity scale, as well as a weak trend of Cepheid colours with metallicity. Conclusions about the absolute effect of metallicity on Cepheid mean magnitudes are limited by the available data on the metallicity gradient in NGC 4258, but our Cepheid data require at least some metallicity adjustment to make the Cepheid distance consistent with independent distances to the Large Magellanic Cloud (LMC) and NGC 4258. From our ensemble of models and the geometric maser distance of NGC 4258 (μN4258 = 29.40 ± 0.06 mag), we estimate μLMC = 18.57 ± 0.14 mag (51.82 ± 3.23 kpc), including the uncertainties due to metallicity.
We present the reconstructed real-space density and the predicted velocity fields from the Two-Micron All-Sky Redshift Survey (2MRS). The 2MRS is the densest all-sky redshift survey to date and ...includes about 23 200 galaxies with extinction-corrected magnitudes brighter than K
s= 11.25. Our method is based on the expansion of these fields in Fourier-Bessel functions. Within this framework, the linear redshift distortions only affect the density field in the radial direction and can easily be deconvolved using a distortion matrix. Moreover, in this coordinate system, the velocity field is related to the density field by a simple linear transformation. The shot noise errors in the reconstructions are suppressed by means of a Wiener filter which yields a minimum variance estimate of the density and velocity fields. Using the reconstructed real-space density fields, we identify all major superclusters and voids. At 50 h
−1 Mpc, our reconstructed velocity field indicates a backside infall to the Great Attractor region of v
infall= (491 ± 200) (β/0.5) km s−1 in the Local Group frame and v
infall= (64 ± 205) (β/0.5) km s−1 in the cosmic microwave background (CMB) frame and β is the redshift distortion parameter. The direction of the reconstructed dipole agrees well with the dipole derived by Erdoğdu et al. The misalignment between the reconstructed 2MRS and the CMB dipoles drops to 13° at around 5000 km s−1 but then increases at larger distances.
Human hair is frequently encountered as forensic evidence and can contribute valuable information to investigators. Conventional forensic hair analyses include microscopic hair comparison (MHC) and ...DNA analysis. However, MHC is not supported by statistics and DNA analysis cannot always be performed. Recent studies have demonstrated that evaluation of differences in the hair proteins may offer an alternate method to these analyses. In this study, an evaluation of the amino acids present in hair was investigated as an approach to differentiate morphologically indistinguishable hair samples from two demographically similar individuals. Proteins in the hair were digested using hydrochloric acid, and the resulting amino acids were derivatized with N,O‐Bis(trimethylsilyl)trifluoroacetamide (BSTFA) for analysis using gas chromatography‐mass spectrometry (GC‐MS). Eight derivatized amino acids were detected and quantified relative to an internal standard, L‐norvaline, and used to construct twenty‐eight amino acid ratios. Hair samples were collected from four areas of the head on various days over the course of one month, and no significant differences in amino acid ratios (p‐value > 0.05) were observed among the areas of the head, and the ratios were consistent over the time period of this study. Additionally, fifteen of these amino acid ratios were found to be significantly different between the two individuals when compared using a two‐sample t‐test (p‐value ≤ 0.05). These data indicate that amino acid analysis was able to differentiate two morphologically similar hair samples from different individuals and demonstrates the applicability of this method to distinguish similar hair samples when DNA analysis cannot be performed.
Traditionally, postpartum care is confined to inpatient care immediately post birth and one appointment approximately six weeks postpartum. Data supports a continuum of care model as best for the ...health of mother and baby. Despite most women having significant concerns about the postpartum period, these concerns are frequently incompletely addressed by providers. We surveyed prenatal and postpartum patients to understand their concerns and experiences discussing postpartum care with providers.
Cross sectional surveys were administered between June 2019 and May 2021. Principal component analysis was used to show higher than average (positive) or lower than average (negative) conversations with providers about postpartum care examined by race, education, and parity. Chi squared tests were conducted to examine the significance of specific postpartum concerns.
421/450 patient surveys were analyzed, based on completion. Most patients were White (193), had post graduate degrees (188), privately insured (236), married (248), first time pregnant (152), and used doctors as their primary provider (267). Patients with lower education, higher parity and Black patients without postgraduate degrees reported higher than average postpartum counseling. Additionally, most patients expressed significant concerns about postpartum exhaustion (65.8%), breastfeeding (62.3%), pain (61.2%), physical activity (54.9%) and the baby blues (50.4%).
Postpartum concerns are incompletely and inconsistently addressed amongst patients based on race, parity, and education. A continuum of care approach, beginning in the third trimester, through the postpartum period, may provide better counseling to address all patients' concerns.
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