Resurrection of Traditional Luminosity Evolution Models to Explain Faint Field Galaxies

We explore the nature of the evolution of faint field galaxies by assuming that the local luminosity function is not well defined. We use a non-negative least squares technique to derive a near optimal set of local luminosity functions for different spectral types of galaxies by fitting to the observed optical and near-infrared counts, B-R colors, and redshift distributions for galaxies with 15 < B < 27. We report here the results of using only traditional luminosity evolution (ie. the photometric evolution of stars in a galaxy over time given reasonable assumptions of the form of the star formation history for various galaxy types), and simple galaxy reddening and find excellent fits to the observed data to B = 27. We conclude that models more exotic than traditional luminosity evolution are not yet required to explain existing faint field galaxy data and thus the need for contributions by mergers or new populations of galaxies is at least 5x less than previously estimated.Comment: 9 pages + 1 table + 4 figures; uuencoded tar compressed postscript; to be published in The Astrohysical Journal Letter

Prevalence of vitamin D insufficiency and risk factors for type 2 diabetes and cardiovascular disease among African migrant and refugee adults in Melbourne

Migration to industrialised countries poses a &ldquo;double whammy&rdquo; for type 2 diabetes among sub-Saharan African migrant and refugee adults. This population group has been found to be at an increased risk of obesity and type 2 diabetes, which may be further aggravated by inadequate vitamin D status. Thus, this study aimed to describe the demographics of vitamin D insufficiency, obesity, and risk factors for type 2 diabetes among sub-Saharan African migrants and refugees aged 20 years or older living in Melbourne, Australia (n=49). Data were obtained by a questionnaire, medical assessment, and fasting blood samples. The mean serum 25-hydroxyvitamin D level was 27.3 nmol/L (95% CI: 22.2, 32.4 nmol/L); with 25-hydroxyvitamin D levels &lt;50 nmol/L occurring in 88% of participants. Participants displayed a cluster of risk factors for type 2 diabetes and cardiovascular disease: 62% were overweight or obese, 47% had insulin resistance (HOMA-IR &ge;2), 25% had low density lipoprotein cholesterol levels &ge;3.5 mmol/L, 24.5% had high density lipoprotein cholesterol levels &le;1.03 mmol/L, 34.6% had borderline or high levels of total cholesterol (&ge;5.2 mmol/L), 18.2% had borderline or high levels of triglyceride (&ge;1.7 mmol/L), and 16% had hypertension (systolic blood pressure &ge;140 mmHg or diastolic blood pressure &ge;90 mmHg). These findings suggest that sub-Saharan African migrants and refugees may be at risk of type 2 diabetes and atherosclerosis-related diseases such as ischemic heart disease, stroke, and peripheral vascular disease. Well-designed vitamin D interventions that incorporate lifestyle changes are urgently needed in this sub-population.<br /

Revolution and the end of history: Caryl Churchill's Mad Forest

Caryl Churchill’s Mad Forest, written and performed very soon after the Romanian revolution in 1990 and performed both in London and Bucharest, is a dynamic, inter-cultural play that represents a variety of perspectives on the revolutionary events, as well as oscillating between English and Romanian cultural and language coordinates. It has a peculiar topicality in its detailed and specific usages of different aspects of the revolutionary narrative, its sketches of family life before and after the revolution, and the inclusion of the revolution as reported in quasi-documentary-style testimony. The perspective in this article is one that places the play within a framework that thinks through Mad Forest’s relationship to the triumphant, neoliberalist heralding of “the end of history,” most famously argued by Francis Fukuyama in his 1989 article of that name. This discourse gained further confidence from the collapse of Eastern Europe, a collapse that was viewed by proponents of the end-of-history argument as signalling the permanent disintegration of communism and a victory for capitalism. However, Mad Forest is considered here as a play that reflects multiple perspectives on the revolutionary period and, while declining to provide political solutions as such, simultaneously refuses to accede to the implications of the end-of-history argument

Associations between dietary iron and zinc intakes, and between biochemical iron and zinc status in women

Iron and zinc are found in similar foods and absorption of both may be affected by food compounds, thus biochemical iron and zinc status may be related. This cross-sectional study aimed to: (1) describe dietary intakes and biochemical status of iron and zinc; (2) investigate associations between dietary iron and zinc intakes; and (3) investigate associations between biochemical iron and zinc status in a sample of premenopausal women aged 18&ndash;50 years who were recruited in Melbourne and Sydney, Australia. Usual dietary intakes were assessed using a 154-item food frequency questionnaire (n = 379). Iron status was assessed using serum ferritin and hemoglobin, zinc status using serum zinc (standardized to 08:00 collection), and presence of infection/inflammation using C-reactive protein (n = 326). Associations were explored using multiple regression and logistic regression. Mean (SD) iron and zinc intakes were 10.5 (3.5) mg/day and 9.3 (3.8) mg/day, respectively. Median (interquartile range) serum ferritin was 22 (12&ndash;38) &mu;g/L and mean serum zinc concentrations (SD) were 12.6 (1.7) &mu;mol/L in fasting samples and 11.8 (2.0) &mu;mol/L in nonfasting samples. For each 1 mg/day increase in dietary iron intake, zinc intake increased by 0.4 mg/day. Each 1 &mu;mol/L increase in serum zinc corresponded to a 6% increase in serum ferritin, however women with low serum zinc concentration (AM fasting &lt; 10.7 &mu;mol/L; AM nonfasting &lt; 10.1 &mu;mol/L) were not at increased risk of depleted iron stores (serum ferritin &lt;15 &mu;g/L; p = 0.340). Positive associations were observed between dietary iron and zinc intakes, and between iron and zinc status, however interpreting serum ferritin concentrations was not a useful proxy for estimating the likelihood of low serum zinc concentrations and women with depleted iron stores were not at increased risk of impaired zinc status in this cohort

Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South

We describe the results of an extremely deep, 0.28 deg^2 survey for z = 3.1 Ly-alpha emission-line galaxies in the Extended Chandra Deep Field South. By using a narrow-band 5000 Anstrom filter and complementary broadband photometry from the MUSYC survey, we identify a statistically complete sample of 162 galaxies with monochromatic fluxes brighter than 1.5 x 10^-17 ergs cm^-2 s^-1 and observers frame equivalent widths greater than 80 Angstroms. We show that the equivalent width distribution of these objects follows an exponential with a rest-frame scale length of w_0 = 76 +/- 10 Angstroms. In addition, we show that in the emission line, the luminosity function of Ly-alpha galaxies has a faint-end power-law slope of alpha = -1.49 +/- 0.4, a bright-end cutoff of log L^* = 42.64 +/- 0.2, and a space density above our detection thresholds of 1.46 +/- 0.12 x 10^-3 h70^3 galaxies Mpc^-3. Finally, by comparing the emission-line and continuum properties of the LAEs, we show that the star-formation rates derived from Ly-alpha are ~3 times lower than those inferred from the rest-frame UV continuum. We use this offset to deduce the existence of a small amount of internal extinction within the host galaxies. This extinction, coupled with the lack of extremely-high equivalent width emitters, argues that these galaxies are not primordial Pop III objects, though they are young and relatively chemically unevolved.Comment: 45 pages, 15 figures, accepted for publication in the Astrophysical Journa

Discovery of Two Distant Type Ia Supernovae in the Hubble Deep Field North with the Advanced Camera for Surveys

We present observations of the first two supernovae discovered with the recently installed Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The supernovae were found in Wide Field Camera images of the Hubble Deep Field North taken with the F775W, F850LP, and G800L optical elements as part of the ACS guaranteed time observation program. Spectra extracted from the ACS G800L grism exposures confirm that the objects are Type Ia supernovae (SNe Ia) at redshifts z=0.47 and z=0.95. Follow-up HST observations have been conducted with ACS in F775W and F850LP and with NICMOS in the near-infrared F110W bandpass, yielding a total of 9 flux measurements in the 3 bandpasses over a period of 50 days in the observed frame. We discuss many of the important issues in doing accurate photometry with the ACS. We analyze the multi-band light curves using two different fitting methods to calibrate the supernovae luminosities and place them on the SNe Ia Hubble diagram. The resulting distances are consistent with the redshift-distance relation of the accelerating universe model, although evolving intergalactic grey dust remains as a less likely possibility. The relative ease with which these SNe Ia were found, confirmed, and monitored demonstrates the potential ACS holds for revolutionizing the field of high-redshift SNe Ia, and therefore of testing the accelerating universe cosmology and constraining the "epoch of deceleration".Comment: 11 pages, 8 embedded figures. Accepted for publication in Ap

Lower protein-to-carbohydrate ratio in maternal diet is associated with higher childhood systolic blood pressure up to age four years

The prenatal environment can influence development of offspring blood pressure (BP), which tracks into adulthood. This prospective longitudinal study investigated whether maternal pregnancy dietary intake is associated with the development of child BP up to age four years. Data are from 129 mother-child dyads enrolled in the Women and Their Children\u27s Health study. Maternal diet was assessed using a validated 74-item food frequency questionnaire at 18 to 24 weeks and 36 to 40 weeks, with a reference period of the previous three months. Child systolic and diastolic BP were measured at 3, 6, 9, 12, 24, 36 and 48 months, using an automated BP monitor. Using mixed-model regression analyses adjusted for childhood growth indices, pregnancy intakes of percentage of energy (E%) polyunsaturated fat (&beta; coefficient 0.73; 95% CI 0.003, 1.45; p = 0.045), E% omega-6 fatty acids (&beta; coefficient 0.89; 95% CI 0.09, 1.69; p = 0.03) and protein-to-carbohydrate (P:C) ratio (&beta; coefficient -14.14; 95% CI -27.68, -0.60; p = 0.04) were associated with child systolic BP trajectory up to 4 years. Child systolic BP was greatest at low proportions of dietary protein (&lt;16% of energy) and high carbohydrate (&gt;40% of energy) intakes. There may be an ideal maternal macronutrient ratio associated with optimal infant BP. Maternal diet, which is potentially modifiable, may play an important role in influencing offspring risk of future hypertension

Guidelines for the management of postmenopausal osteoporosis for GPs

Copyright © 2004 Royal Australian College of General Practitioners Copyright to Australian Family Physician. Reproduced with permission. Permission to reproduce must be sought from the publisher, The Royal Australian College of General Practitioners.Background: Since the last series of guidelines on the management of osteoporosis from Osteoporosis Australia was published in Australian Family Physician (October 2002), there have been further advances in our understanding of the treatment involved in both the prevention of bone loss and the management of established osteoporosis. Objective: This article provides updated guidelines for the management of postmenopausal osteoporosis to assist general practitioners identify those women at risk, and reviews current treatment strategies. DISCUSSION: Osteoporosis and its associated problems are major health concerns in Australia, especially with an aging population. While important principles of management are still considered to be maximising peak bone mass and preventing postmenopausal bone loss, new clinical trial data about drugs such as the bisphosphonates, raloxifene and oestrogen have recently become available and the relative role of various agents is gradually becoming clearer. The use of long term hormone therapy has mixed risks and benefits that requires individual patient counselling.O'Neill S; MacLennan A; Bass S; Diamond T; Ebeling P; Findlay D; Flicker L; Markwell A; Nowson C; Pocock N; Sambrook P; Singh M

GRB 060313: A New Paradigm for Short-Hard Bursts?

We report the simultaneous observations of the prompt emission in the gamma-ray and hard X-ray bands by the Swift-BAT and the KONUS-Wind instruments of the short-hard burst, GRB 060313. The observations reveal multiple peaks in both the gamma-ray and hard X-ray bands suggesting a highly variable outflow from the central explosion. We also describe the early-time observations of the X-ray and UV/Optical afterglows by the Swift XRT and UVOT instruments. The combination of the X-ray and UV/Optical observations provide the most comprehensive lightcurves to date of a short-hard burst at such an early epoch. The afterglows exhibit complex structure with different decay indices and flaring. This behavior can be explained by the combination of a structured jet, radiative loss of energy, and decreasing microphysics parameters occurring in a circum-burst medium with densities varying by a factor of approximately two on a length scale of 10^17 cm. These density variations are normally associated with the environment of a massive star and inhomogeneities in its windy medium. However, the mean density of the observed medium (n approximately 10^&#8722;4 cm^3) is much less than that expected for a massive star. Although the collapse of a massive star as the origin of GRB 060313 is unlikely, the merger of a compact binary also poses problems for explaining the behavior of this burst. Two possible suggestions for explaining this scenario are: some short bursts may arise from a mechanism that does not invoke the conventional compact binary model, or soft late-time central engine activity is producing UV/optical but no X-ray flaring.Comment: 28 pages, 6 figures. Accepted for publication in ApJ. Clarifications made and typos correcte