The Stars in M15 Were Born with the r-process

High-resolution spectroscopy of stars on the red giant branch (RGB) of the globular cluster M15 has revealed a large (~1 dex) dispersion in the abundances of r-process elements such as Ba and Eu. Neutron star mergers (NSMs) have been proposed as a major source of the r-process. However, most NSM models predict a delay time longer than the timescale for cluster formation. One possibility is that a NSM polluted the surfaces of stars in M15 long after the cluster finished forming. In this case, the abundances of the polluting elements would decrease in the first dredge-up as stars turn on to the RGB. We present Keck/DEIMOS abundances of Ba in 66 stars along the entire RGB and the top of the main sequence. The Ba abundances have no trend with stellar luminosity (evolutionary phase). Therefore, the stars were born with the Ba that they have today, and Ba did not originate in a source with a delay time longer than the timescale for cluster formation. In particular, if the source of Ba was a NSM, it would have had a very short delay time. Alternatively, if Ba enrichment took place before the formation of the cluster, an inhomogeneity of a factor of 30 in Ba abundance needs to be able to persist over the length scale of the gas cloud that formed M15, which is unlikely

Neutron Star Mergers Are the Dominant Source of the r-process in the Early Evolution of Dwarf Galaxies

There are many candidate sites of the r-process: core-collapse supernovae (including rare magnetorotational core-collapse supernovae), neutron star mergers, and neutron star/black hole mergers. The chemical enrichment of galaxies---specifically dwarf galaxies---helps distinguish between these sources based on the continual build-up of r-process elements. This technique can distinguish between the r-process candidate sites by the clearest observational difference---how quickly these events occur after the stars are created. The existence of several nearby dwarf galaxies allows us to measure robust chemical abundances for galaxies with different star formation histories. Dwarf galaxies are especially useful because simple chemical evolution models can be used to determine the sources of r-process material. We have measured the r-process element barium with Keck/DEIMOS medium-resolution spectroscopy. We present the largest sample of barium abundances (almost 250 stars) in dwarf galaxies ever assembled. We measure [Ba/Fe] as a function of [Fe/H] in this sample and compare with existing [alpha/Fe] measurements. We have found that a large contribution of barium needs to occur at more delayed timescales than core-collapse supernovae in order to explain our observed abundances, namely the significantly more positive trend of the r-process component of [Ba/Fe] vs. [Fe/H] seen for [Fe/H] <~ -1.6 when compared to the [Mg/Fe] vs. [Fe/H] trend. We conclude that neutron star mergers are the most likely source of r-process enrichment in dwarf galaxies at early times.Comment: Accepted to ApJ on 2018 October 2

Estimating the Impact of Medical Innovation: A Case Study of HIV Antiretroviral Treatments

As health care consumes a growing share of GDP, the demand for better evidence regarding the effects of health care treatments and how these vary across individuals is increasing. Estimating this with observational data is difficult given the endogeneity of treatment decisions. But because the random assignment clinical trials (RACTs) used in the FDA approval process only estimate average health effects and do not consider spending, there is no good alternative. In this study we use administrative data from California’s Medicaid program to estimate the impact of HIV antiretroviral treatments (ARVs). We use data on health care utilization to proxy for health status and exploit the rapid takeup of ARVs following their FDA approval. Our estimate of a 68 percent average mortality rate reduction is in line with the results from RACTs. We also find that the ARVs lowered short-term health care spending by reducing expenditures on other categories of medical care. Combining these two effects we estimate the cost per life year saved at $19,000. Our results suggest an alternative method for estimating the real-world effects of new treatments that is especially well-suited to those treatments that diffuse rapidly following their approval

The case for new academic workspaces

Executive summary: This report draws upon the combined efforts of a number of estates professionals, architects, academics, designers, and senior managers involved in the planning of new university buildings for the 21st century. Across these perspectives, all would agree – although perhaps for different reasons - that this planning is difficult and that a number of particular considerations apply in the design of academic workspaces. Despite these difficulties, they will also agree that when this planning goes well, ‘good’ buildings are truly transformational – for both the university as a whole and the people who work and study in them. The value of well-designed buildings goes far beyond their material costs, and endures long after those costs have been forgotten ..

Triangulum II: Not Especially Dense After All

Among the Milky Way satellites discovered in the past three years, Triangulum II has presented the most difficulty in revealing its dynamical status. Kirby et al. (2015a) identified it as the most dark matter-dominated galaxy known, with a mass-to-light ratio within the half-light radius of 3600 +3500 -2100 M_sun/L_sun. On the other hand, Martin et al. (2016) measured an outer velocity dispersion that is 3.5 +/- 2.1 times larger than the central velocity dispersion, suggesting that the system might not be in equilibrium. From new multi-epoch Keck/DEIMOS measurements of 13 member stars in Triangulum II, we constrain the velocity dispersion to be sigma_v < 3.4 km/s (90% C.L.). Our previous measurement of sigma_v, based on six stars, was inflated by the presence of a binary star with variable radial velocity. We find no evidence that the velocity dispersion increases with radius. The stars display a wide range of metallicities, indicating that Triangulum II retained supernova ejecta and therefore possesses or once possessed a massive dark matter halo. However, the detection of a metallicity dispersion hinges on the membership of the two most metal-rich stars. The stellar mass is lower than galaxies of similar mean stellar metallicity, which might indicate that Triangulum II is either a star cluster or a tidally stripped dwarf galaxy. Detailed abundances of one star show heavily depressed neutron-capture abundances, similar to stars in most other ultra-faint dwarf galaxies but unlike stars in globular clusters.Comment: accepted to ApJ, Table 5 available as a machine-readable table by clicking on "Other formats" on the right. Proof corrections reflected in version

A robust procedure for the measurement of Serum Magnesium on the Hitachi 704 using Calmagite

peer-reviewedA robust procedure for measurement of magnesium in serum is described using calmagite in CAPS buffer at pH 11.5. Interference from other magnesium reagents was reduced and evaluated for chromophoric interference. The procedure was not effected by bilirubin or hemoglobin in serum samples

Insm1 promotes the transition of olfactory progenitors from apical and proliferative to basal, terminally dividing and neuronogenic

<p>Abstract</p> <p>Background</p> <p>Insm1 is a zinc-finger transcription factor transiently expressed throughout the developing nervous system in late progenitors and nascent neurons. Insm1 is also highly expressed in medulloblastomas and other neuroendocrine tumors.</p> <p>Results</p> <p>We generated mice lacking the <it>Insm1 </it>gene and used them to elucidate its role in neurogenic proliferation of the embryonic olfactory epithelium. We found that deletion of <it>Insm1 </it>results in more apical cells and fewer nascent and mature neurons. In the embryonic olfactory epithelium of <it>Insm1 </it>mutants we detect fewer basal progenitors, which produce neurons, and more apical progenitors, which at this stage produce additional progenitors. Furthermore, in the mutants we detect fewer progenitors expressing NEUROD1, a marker of terminally dividing, neuronogenic (neuron-producing) progenitors (immediate neuronal precursors), and more progenitors expressing ASCL1, a marker of the transit amplifying progenitors that migrate from the apical to the basal edges of the epithelium while dividing to generate the terminal, neuronogenic progenitors. Finally, with timed administration of nucleoside analogs we demonstrate that the <it>Insm1 </it>mutants contain fewer terminally dividing progenitors at embryonic day 12.5.</p> <p>Conclusions</p> <p>Altogether, these results suggest a role for <it>Insm1 </it>in promoting the transition of progenitors from apical and proliferative to basal, terminal and neuronogenic. This role appears partially conserved with that of its nematode ortholog, <it>egl-46</it>. The similar effects of <it>Insm1 </it>deletion on progenitors of embryonic olfactory epithelium and cortex point to striking parallels in the development of these neuroepithelia, and particularly between the basal progenitors of olfactory epithelium and the subventricular zone progenitors of cortex.</p

What More Can Be Done? Childhood Obesity in Glassboro, NJ

Childhood obesity is a growing public health concern in the United States, with an estimated 20% of American children being obese. In New Jersey (NJ), 9% of high school students are obese, and there are disparities in obesity rates based on gender, sexual identity, and race/ethnicity. In Gloucester County, NJ, limited data is available on childhood obesity rates, but 36.4% of adults are obese, and lower SES is related to higher rates of obesity in youth. To address this issue, this research poster proposes a partnership with the Boys and Girls Club of Glassboro to provide nutritional resources and create monthly newsletters for parents and guardians, with the aim of promoting access to affordable produce and grocery stores in the area. This intervention could potentially help reduce rates of childhood obesity in Glassboro, NJ. Limitations of the study include limited data availability and difficulty in finding meaningful and sustainable intervention ideas

Psychological perspectives in urinary incontinence: a metasynthesis

Introduction: Urinary incontinence with co-morbid depression has been found to have a significant effect on quality of life. Examining the associations between the psychosocial factors related to urinary incontinence and mental health may help in improving the care for patients with these conditions. The aim of this research study is to explore the relationship between mental health status and urinary incontinence, focusing on the role of psychosocial factors. Materials and Methods: A search of Medline, CINAHL and SCOPUS databases yielded 15 studies on the topic, and 10 studies were found to be in scope. A metasynthesis using Noblit and Hare’s approach of meta-ethnography was undertaken. This involved a number of steps including determining how studies are related and identifying major themes. Results: Three psychosocial aspects of urinary incontinence appear to influence mental health status: living with, management of and attitudes about incontinence. Other smaller component themes included control, seeking help and personal beliefs. Discussion: Psychosocial factors appear to mediate the relationship between urinary incontinence and mental health status. An increased awareness of the major psychosocial issues that can influence both incontinence and mental health may contribute to a better management of the condition as well as reduce the burden of the condition on individuals. Conclusion: Incontinence and psychological wellbeing are intertwined and this adversely affects a number of aspects of life. Enquiring about the mental health status of those with incontinence should include an assessment of psychosocial factors to help reduce the burden of incontinence. To improve the management of these conditions, further research should investigate whether psychological issues precede incontinence or vice versa.JC Avery, AJ Braunack-Mayer, NP Stocks, AW Taylor, P Dugga