The Mass-Loss Return From Evolved Stars to The Large Magellanic Cloud VI: Luminosities and Mass-Loss Rates on Population Scales

We present results from the first application of the Grid of Red Supergiant and Asymptotic Giant Branch ModelS (GRAMS) model grid to the entire evolved stellar population of the Large Magellanic Cloud (LMC). GRAMS is a pre-computed grid of 80,843 radiative transfer (RT) models of evolved stars and circumstellar dust shells composed of either silicate or carbonaceous dust. We fit GRAMS models to ~30,000 Asymptotic Giant Branch (AGB) and Red Supergiant (RSG) stars in the LMC, using 12 bands of photometry from the optical to the mid-infrared. Our published dataset consists of thousands of evolved stars with individually determined evolutionary parameters such as luminosity and mass-loss rate. The GRAMS grid has a greater than 80% accuracy rate discriminating between Oxygen- and Carbon-rich chemistry. The global dust injection rate to the interstellar medium (ISM) of the LMC from RSGs and AGB stars is on the order of 1.5x10^(-5) solar masses/yr, equivalent to a total mass injection rate (including the gas) into the ISM of ~5x10^(-3) solar masses/yr. Carbon stars inject two and a half times as much dust into the ISM as do O-rich AGB stars, but the same amount of mass. We determine a bolometric correction factor for C-rich AGB stars in the K band as a function of J - K color, BC(K) = -0.40(J-K)^2 + 1.83(J-K) + 1.29. We determine several IR color proxies for the dust mass-loss rate (MLR) from C-rich AGB stars, such as log (MLR) = (-18.90)/((K-[8.0])+3.37)-5.93. We find that a larger fraction of AGB stars exhibiting the `long-secondary period' phenomenon are O-rich than stars dominated by radial pulsations, and AGB stars without detectable mass-loss do not appear on either the first-overtone or fundamental-mode pulsation sequences.Comment: 19 pages, 19 figure

An Underpinning of School Inequities: Asthma Absences and Lost Revenue in California Schools.

BACKGROUND:Asthma is epidemic in many locations in the United States. Asthma exacerbations pose serious health and education risks for students through school absences, school dropout, and introduction to the juvenile justice system. Accurate school district-level asthma data, currently in short supply, would enable early interventions that focus on specific geographic areas and racial and ethnic subgroups that have higher asthma prevalence. METHODS:To support the development of better local level data systems, we used two California student databases, as well as state education and financial databases, to develop two models to estimate school absences and to extrapolate their economic impact in lost school revenue. RESULTS:Analysis demonstrated subpopulations that are appropriate for early intervention: African American elementary school boys have 9.4 average absences per year, higher than other primary racial and ethnic groups. Students who miss ≥3 school days due to asthma account for $26 million of lost revenue. CONCLUSIONS:Accurate local level asthma data can identify subpopulations of students for whom environmental and treatment programs can be employed to reduce asthma absences and other related outcomes, and to reduce currently lost school revenues. Such programs also may diminish other asthma-related school inequities

The contribution of starbursts and normal galaxies to infrared luminosity functions at z < 2

We present a parameter-less approach to predict the shape of the infrared (IR) luminosity function (LF) at redshifts z < 2. It requires no tuning and relies on only three observables: (1) the redshift evolution of the stellar mass function for star-forming galaxies, (2) the evolution of the specific star formation rate (sSFR) of main-sequence galaxies, and (3) the double-Gaussian decomposition of the sSFR-distribution at fixed stellar mass into a contribution (assumed redshift- and mass-invariant) from main-sequence and starburst activity. This self-consistent and simple framework provides a powerful tool for predicting cosmological observables: observed IR LFs are successfully matched at all z < 2, suggesting a constant or only weakly redshift-dependent contribution (8-14%) of starbursts to the star formation rate density. We separate the contributions of main-sequence and starburst activity to the global IR LF at all redshifts. The luminosity threshold above which the starburst component dominates the IR LF rises from log(LIR/Lsun) = 11.4 to 12.8 over 0 < z < 2, reflecting our assumed (1+z)^2.8-evolution of sSFR in main-sequence galaxies.Comment: 7 pages, 4 figures & 1 table. Accepted for publication in ApJL. Minor typos corrected in v2 following receipt of proof

The National Imperative For Health Care System Transformation: Why Certain Mergers And Acquistions Are Appropriate Despite Section 7 Of The Clayton Act

Integration among health care providers offers a promising solution to the health care crisis. Unfortunately, some efforts to improve the American health care system through integration have been halted by antitrust concerns and the enforcement of section 7 of the Clayton Act. Health care costs could be contained and clinical quality improved by allowing a narrow statutory exemption to enforcement of section 7 for health care integrations that demonstrate cost efficiency and advance patient care. Under such limited circumstances, relaxed antitrust regulation is an appropriate response to health care’s current financial crisis that will ultimately benefit America’s consumers and economy by transforming the fragmented volumebased health care system to one based on value

Sequence homology between RNAs encoding rat α-fetoprotein and rat serum albumin

We have determined the sequences of the recombinant DNA inserts of three bacterial plasmid cDNA clones containing most of the rat α-fetoprotein mRNA. The resultant nucleotide sequence of α-fetoprotein was exhaustively compared to the nucleotide sequence of the mRNA encoding rat serum albumin. These two mRNAs have extensive homology (50%) throughout and the same intron locations. The amino acid sequence of rat α-fetoprotein has been deduced from the nucleotide sequence, and its comparison to rat serum albumin's amino acid sequence reveals a 34% homology. The regularly spaced positions of the cysteines found in serum albumin are conserved in rat α-fetoprotein, indicating that these two proteins may have a similar secondary folding structure. These homologies indicate that α-fetoprotein and serum albumin were derived by duplication of a common ancestral gene and constitute a gene family