We present results for the assembly and star formation histories (SFHs) of massive (~L*) red sequence galaxies (RSGs) in 11 spectroscopically confirmed, infrared-selected galaxy clusters at 1.0 < z < ...1.5, the precursors to present-day massive clusters with M ~ 10 super(15) M sub(middot in circle). Using rest-frame optical photometry, we investigate evolution in the color and scatter of the RSG population, comparing with models of possible SFHs. In contrast to studies of central cluster galaxies at lower redshift (z < 1), these data are clearly inconsistent with the continued evolution of stars formed and assembled primarily at a single, much earlier time. Specifically, we find that the colors of massive cluster galaxies at z asymptotically = 1.5 imply that the bulk of star formation occurred at z ~ 3, whereas by z asymptotically = 1 their colors imply formation at z ~ 2; therefore these galaxies exhibit approximately the same luminosity-weighted stellar age at 1 < z < 1.5. This likely reflects star formation that occurs over an extended period, the effects of significant progenitor bias, or both. Our results generally indicate that massive cluster galaxy populations began forming a significant mass of stars at z > ~ 4, contained some red spheroids by z asymptotically = 1.5, and were actively assembling much of their final mass during 1 < z < 2 in the form of younger stars. Qualitatively, the slopes of the cluster color-magnitude relations are consistent with no significant evolution relative to local clusters.
Purpose The objective of this study was to investigate the effects of polymer type and storage relative humidity (RH) on the crystallization kinetics of felodipine from amorphous solid dispersions. ...Methods Crystallization of the model drug felodipine from amorphous solid dispersion samples containing poly(vinyl pyrrolidone) (PVP) and hypromellose acetate succinate (HPMCAS) were evaluated. Samples at three different drug-polymer weight ratios (10, 25, and 50 wt. % polymer) were prepared and stored at six different RHs (0%, 32%, 52% or 66%, 75%, 86%, and 93%). Periodically, the fraction of the drug that had crystallized from the samples was quantified using powder X-ray diffractometry (PXRD). Results Felodipine crystallization rates from PVP-containing dispersions were found to be very sensitive to changes in storage RH, while crystallization rates from HPMCAS-containing dispersions were not. PVP and HPMCAS were similar in terms of their ability to inhibit crystallization at low RH, but when the storage RH was increased to 75% or above, felodipine crystallization from PVP-containing solid dispersions proceeded much faster. It is hypothesized that this trend was caused by moisture-induced drug-polymer immiscibility in PVP-felodipine system. For PVP-containing solid dispersion samples stored at 75% RH and above, crystallization of the model drug felodipine seemed to approach a kinetic plateau, whereby a fraction of the drug still remained amorphous even after storage for 500 days or more. Conclusions The physical stability of solid dispersions as a function of RH is highly dependent on the polymer used to form the solid dispersion, with PVP-containing dispersions being much less physically stable at high RH than HPMCAS-containing dispersions.
Despite numerous clinical studies supporting a link between type 2 diabetes (T2D) and Parkinson's disease (PD), the clinical literature remains equivocal. We, therefore, sought to address the ...relationship between insulin resistance and nigrostriatal dopamine (DA) in a preclinical animal model. High-fat feeding in rodents is an established model of insulin resistance, characterized by increased adiposity, systemic oxidative stress, and hyperglycemia. We subjected rats to a normal chow or high-fat diet for 5 wk before infusing 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle. Our goal was to determine whether a high-fat diet and the resulting peripheral insulin resistance would exacerbate 6-OHDA-induced nigrostriatal DA depletion. Prior to 6-OHDA infusion, animals on the high-fat diet exhibited greater body weight, increased adiposity, and impaired glucose tolerance. Two weeks after 6-OHDA, locomotor activity was tested, and brain and muscle tissue was harvested. Locomotor activity did not differ between the groups nor did cholesterol levels or measures of muscle atrophy. High-fat-fed animals exhibited higher homeostatic model assessment of insulin resistance (HOMA-IR) values and attenuated insulin-stimulated glucose uptake in fast-twitch muscle, indicating decreased insulin sensitivity. Animals in the high-fat group also exhibited greater DA depletion in the substantia nigra and the striatum, which correlated with HOMA-IR and adiposity. Decreased phosphorylation of HSP27 and degradation of IκBα in the substantia nigra indicate increased tissue oxidative stress. These findings support the hypothesis that a diet high in fat and the resulting insulin resistance may lower the threshold for developing PD, at least following DA-specific toxin exposure.
We report the discovery of an IR-selected galaxy cluster in the IRAC Distant Cluster Survey (IDCS). New data from the Hubble Space Telescope spectroscopically confirm IDCS J1433.2+3306 at z = 1.89 ...with robust spectroscopic redshifts for seven members, two of which are based on the 4000 Angstrom break. Detected emission lines such as OII and H beta indicate star formation rates of > ~20 M sub(middot in circle) yr super(-1) for three galaxies within a 500 kpc projected radius of the cluster center. The cluster exhibits a red sequence with a scatter and color indicative of a formation redshift z sub(f) > ~ 3.5. The stellar age of the early-type galaxy population is approximately consistent with those of clusters at lower redshift (1 < z < 1.5) suggesting that clusters at these redshifts are experiencing ongoing or increasing star formation.
Introduction: Sexual Assault Nurse Examiners (SANE), who are trained to provide comprehensive and compassionate specialty care to sexual assault survivors, are increasingly used in the emergency ...department (ED), but there is little published literature to support their benefit. In this study we aimed to compare services offered and received by sexual assault survivors in the ED when care was provided by a SANE vs those with traditional care teams, hypothesizing that SANE utilization will be associated with improved uptake of recommended services. Methods: This was a retrospective review examining all patient encounters in which a sexual assault was disclosed in a large, urban, adult ED between June 1, 2019–June 30, 2022. We extracted timeline information from the ED encounter, demographic information, resources offered to and accepted by the patient, clinical care data, and continuity of care data from the medical record. We used unadjusted and adjusted analyses to compare patient demographics and services offered and accepted between SANE and non-SANE encounters. Results: We included a total of 182 encounters in the analysis, of which 130 (71.4%) involved SANEs. Demographics were similar between groups, except there was a larger proportion of cisgender men in the non-SANE group (14.0% vs 5.5%), and the timing of visits differed, with non-SANE visits more common during the overnight shift. All recommended testing, prophylaxis, and resources were offered more frequently during SANE visits, and all but one were more frequently accepted by patients during SANE visits, although not all comparisons reached statistical significance. Conclusion: Patients who received care from a SANE were more often offered recommended services and resources and more frequently accepted them. Making SANE care available at all times to these vulnerable patients would both improve patient outcomes and allow hospitals to meet required quality metrics. States should consider expanding legislation to encourage and fund SANE coverage for all hospitals to support access to vital resources in the ED for survivors of sexual assault.
ABSTRACT We present a deep (100 ks) Chandra observation of IDCS J1426.5+3508, a spectroscopically confirmed, infrared-selected galaxy cluster at z = 1.75. This cluster is the most massive galaxy ...cluster currently known at z > 1.5, based on existing Sunyaev-Zel'dovich (SZ) and gravitational lensing detections. We confirm this high mass via a variety of X-ray scaling relations, including TX-M, fg-M, YX-M, and LX-M, finding a tight distribution of masses from these different methods, spanning M500 = 2.3-3.3 × 1014M , with the low-scatter YX-based mass = M . IDCS J1426.5+3508 is currently the only cluster at z > 1.5 for which X-ray, SZ, and gravitational lensing mass estimates exist, and these are in remarkably good agreement. We find a relatively tight distribution of the gas-to-total mass ratio, employing total masses from all of the aforementioned indicators, with values ranging from fgas,500 = 0.087-0.12. We do not detect metals in the intracluster medium (ICM) of this system, placing a 2 upper limit of . This upper limit on the metallicity suggests that this system may still be in the process of enriching its ICM. The cluster has a dense, low-entropy core, offset by ∼30 kpc from the X-ray centroid, which makes it one of the few "cool core" clusters discovered at z > 1, and the first known cool core cluster at z > 1.2. The offset of this core from the large-scale centroid suggests that this cluster has had a relatively recent ( 500 Myr) merger/interaction with another massive system.
The properties of galaxy clusters as a function of redshift can be utilized as an important cosmological tool. We present initial results from a program of follow-up observations of the ...Sunyaev-Zeldovich effect (SZE) in high-redshift galaxy clusters detected by the Massive and Distant Clusters of WISE Survey (MaDCoWS) which uses infrared data from the Wide-field Infrared Survey (WISE) instrument. Using typical on-source integration times of 3-4 hr per cluster, MUSTANG2 on the Green Bank Telescope was able to measure strong detections of SZE decrements and statistically significant masses on 14 out of 16 targets. On the remaining two, weaker (3.7 ) detections of the SZE signal and strong upper limits on the masses were obtained. In this paper we present masses and pressure profiles of each target and outline the data analysis used to recover these quantities. Of the clusters with strong detections, three show significantly flatter pressure profiles while, from the MUSTANG2 data, five others show signs of disruption at their cores. However, outside of the cores of the clusters, we were unable to detect significant amounts of asymmetry. Finally, there are indications that the relationship between optical richness used by MaDCoWS and SZE-inferred mass may be significantly flatter than indicated in previous studies.
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