A New Population of Planetary Nebulae Discovered in the Large Magellanic Cloud (III): The Luminosity Function

Our previous identification and spectroscopic confirmation of 431 faint, new planetary nebulae in the central 25 deg^2 region of the LMC permits us to now examine the shape of the LMC Planetary Nebula Luminosity Function (PNLF) through an unprecedented 10 magnitude range. The majority of our newly discovered and previously known PNe were observed using the 2dF, multi-object fibre spectroscopy system on the 3.9-m Anglo-Australian Telescope and the FLAMES multi-object spectrograph on the 8-m VLT. We present reliable [OIII]5007 and H-beta flux estimates based on calibrations to well established PN fluxes from previous surveys and spectroscopic standard stars. The bright cutoff (M*) of the PNLF is found by fitting a truncated exponential curve to the bright end of the PNLF over a 3.4 magnitude range. This cutoff is used to estimate a new distance modulus of 18.46 to the LMC, in close agreement with previous PNLF studies and the best estimates by other indicators. The bright end cutoff is robust to small samples of bright PNe since significantly increased PN samples do not change this fiducial. We then fit a truncated exponential curve directly to the bright end of the function over a 6 magnitude range and test the curve's ability to indicate the position of M*. Because of the significant increase in the number of LMC PN, the shape of the PNLF is now examined in greater detail than has previously been possible. Through cumulative functions, the new LMC PNLF is compared to those from the SMC and a new deep local Galactic sample revealing the effects of incompleteness. The new [OIII]5007 LMC PNLF is then compared to our new H-beta LMC PNLF using calibrated and measured fluxes for the same objects, revealing the effects of metallicity on the [OIII]5007 line.Comment: 28 pages, 24 figures. Accepted MNRA

The Legacy of the U. S. Public Health Service Study of Untreated Syphilis in African American Men at Tuskegee on the Affordable Care Act and Health Care Reform Fifteen Years after President Clinton's Apology

http://dx.doi.org/10.1080/10508422.2012.73080

The Herschel-ATLAS: magnifications and physical sizes of 500-μm-selected strongly lensed galaxies

We perform lens modelling and source reconstruction of Sub-millimetre Array (SMA) data for a sample of 12 strongly lensed galaxies selected at 500μm in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). A previous analysis of the same data set used a single Sérsic profile to model the light distribution of each background galaxy. Here we model the source brightness distribution with an adaptive pixel scale scheme, extended to work in the Fourier visibility space of interferometry. We also present new SMA observations for seven other candidate lensed galaxies from the H-ATLAS sample. Our derived lens model parameters are in general consistent with previous findings. However, our estimated magnification factors, ranging from 3 to 10, are lower. The discrepancies are observed in particular where the reconstructed source hints at the presence of multiple knots of emission. We define an effective radius of the reconstructed sources based on the area in the source plane where emission is detected above 5σ. We also fit the reconstructed source surface brightness with an elliptical Gaussian model. We derive a median value reff ∼ 1.77 kpc and a median Gaussian full width at half-maximum ∼1.47 kpc. After correction for magnification, our sources have intrinsic star formation rates (SFR) ∼ 900–3500 M⊙ yr−1, resulting in a median SFR surface density ΣSFR ∼ 132 M⊙ yr−1 kpc−2 (or ∼218 M⊙ yr−1 kpc−2 for the Gaussian fit). This is consistent with that observed for other star-forming galaxies at similar redshifts, and is significantly below the Eddington limit for a radiation pressure regulated starburst

Discursive construction of fatherly suicide

In this article we are interested in stories of sons and daughters about their fathers who completed suicide. The data come from ten interviews with survivors of suicidal death of their fathers. Taking a constructionist view of discourse, we aim to analyse sons’ and daughters’ narratives in the context of two conflicting discourses of (positive) fatherhood and (negative) suicide. We shall show how they use the discursive strategies of distancing in the narratives about fathers’ suicide as a means of coping with the two conflicting discourses. And so, first, they avoid labelling the act as suicide, second, they avoid direct reference to the fact that it was their father who completed the act, third, they dilute the father’s responsibility for the act

Consensus guidelines for the definition, detection and interpretation of immunogenic cell death.

Cells succumbing to stress via regulated cell death (RCD) can initiate an adaptive immune response associated with immunological memory, provided they display sufficient antigenicity and adjuvanticity. Moreover, multiple intracellular and microenvironmental features determine the propensity of RCD to drive adaptive immunity. Here, we provide an updated operational definition of immunogenic cell death (ICD), discuss the key factors that dictate the ability of dying cells to drive an adaptive immune response, summarize experimental assays that are currently available for the assessment of ICD in vitro and in vivo, and formulate guidelines for their interpretation

Patterns of Plant Biomass Partitioning Depend on Nitrogen Source

Nitrogen (N) availability is a strong determinant of plant biomass partitioning, but the role of different N sources in this process is unknown. Plants inhabiting low productivity ecosystems typically partition a large share of total biomass to belowground structures. In these systems, organic N may often dominate plant available N. With increasing productivity, plant biomass partitioning shifts to aboveground structures, along with a shift in available N to inorganic forms of N. We tested the hypothesis that the form of N taken up by plants is an important determinant of plant biomass partitioning by cultivating Arabidopsis thaliana on different N source mixtures. Plants grown on different N mixtures were similar in size, but those supplied with organic N displayed a significantly greater root fraction. 15N labelling suggested that, in this case, a larger share of absorbed organic N was retained in roots and split-root experiments suggested this may depend on a direct incorporation of absorbed amino acid N into roots. These results suggest the form of N acquired affects plant biomass partitioning and adds new information on the interaction between N and biomass partitioning in plants

A Multigenerational View of Inequality

The study of intergenerational mobility and most population research are governed by a two-generation (parent-to-offspring) view of intergenerational influence, to the neglect of the effects of grandparents and other ancestors and nonresident contemporary kin. While appropriate for some populations in some periods, this perspective may omit important sources of intergenerational continuity of family-based social inequality. Social institutions, which transcend individual lives, help support multigenerational influence, particularly at the extreme top and bottom of the social hierarchy, but to some extent in the middle as well. Multigenerational influence also works through demographic processes because families influence subsequent generations through differential fertility and survival, migration, and marriage patterns, as well as through direct transmission of socioeconomic rewards, statuses, and positions. Future research should attend more closely to multigenerational effects; to the tandem nature of demographic and socioeconomic reproduction; and to data, measures, and models that transcend coresident nuclear families