The "Building Blocks" of Stellar Halos

The stellar halos of galaxies encode their accretion histories. In particular, the median metallicity of a halo is determined primarily by the mass of the most massive accreted object. We use hydrodynamical cosmological simulations from the APOSTLE project to study the connection between the stellar mass, the metallicity distribution, and the stellar age distribution of a halo and the identity of its most massive progenitor. We find that the stellar populations in an accreted halo typically resemble the old stellar populations in a present-day dwarf galaxy with a stellar mass $\sim 0.2-0.5$ dex greater than that of the stellar halo. This suggest that had they not been accreted, the primary progenitors of stellar halos would have evolved to resemble typical nearby dwarf irregulars.Comment: 7 pages, 3 figures, published in the proceedings of "On the Origin (and Evolution) of Baryonic Galaxy Halos", Puerto Ayora, Ecuador, March 13-17 2017, Eds. Duncan A. Forbes and Ericson D. Lope

Use of behaviour change techniques in lifestyle change interventions for people with intellectual disabilities: A systematic review

Background: People with intellectual disabilities (ID) experience more health problems and have different lifestyle change needs, compared with the general population. Aims: To improve lifestyle change interventions for people with ID, this review examined how behaviour change techniques (BCTs) were applied in interventions aimed at physical activity, nutrition or physical activity and nutrition, and described their quality. Methods and procedures: After a broad search and detailed selection process, 45 studies were included in the review. For coding BCTs, the CALO-RE taxonomy was used. To assess the quality of the interventions, the Physiotherapy Evidence Database (PEDro) scale was used. Extracted data included general study characteristics and intervention characteristics. Outcomes and results: All interventions used BCTs, although theory-driven BCTs were rarely used. The most frequently used BCTs were ‘provide information on consequences of behaviour in general’ and ‘plan social support/social change’. Most studies were of low quality and a theoretical framework was often missing. Conclusion and implications: This review shows that BCTs are frequently applied in lifestyle change interventions. To further improve effectiveness, these lifestyle change interventions could benefit from using a theoretical framework, a detailed intervention description and an appropriate and reliable intervention design which is tailored to people with ID

Searching for Dust around Hyper Metal-Poor Stars

We examine the mid-infrared fluxes and spectral energy distributions for metal-poor stars with iron abundances [Fe/H] $\lesssim-5$, as well as two CEMP-no stars, to eliminate the possibility that their low metallicities are related to the depletion of elements onto dust grains in the formation of a debris disk. Six out of seven stars examined here show no mid-IR excess. These non-detections rule out many types of circumstellar disks, e.g. a warm debris disk ($T\!\le\!290$ K), or debris disks with inner radii $\le1$ AU, such as those associated with the chemically peculiar post-AGB spectroscopic binaries and RV Tau variables. However, we cannot rule out cooler debris disks, nor those with lower flux ratios to their host stars due to, e.g. a smaller disk mass, a larger inner disk radius, an absence of small grains, or even a multicomponent structure, as often found with the chemically peculiar Lambda Bootis stars. The only exception is HE0107-5240, for which a small mid-IR excess near 10 microns is detected at the 2-$\sigma$ level; if the excess is real and associated with this star, it may indicate the presence of (recent) dust-gas winnowing or a binary system.Comment: Accepted for publication in Ap

Examination of smears for tubercle bacilli by Fluorescence Microscopy

IN underdeveloped countries, laboratory facilities for the bacteriological diagnosis of tuberculosis are at present, very limited. Cultural methods are unlikely to be used on a large scale for many years to come. It is, therefore, important to investigate the most economical method of examining smears for tubercle bacilli. Fluorescence microscopy was introduced by Hagemann (1937) and has since been described by many authors, including Tanner (1941, 1948), Lind and Shaughnessy (1941), Lempert (1944), Norman and Jelks (1945), Clegg and Foster-Carter (1946), Wilson (1952), Von Haebler and Murray (1954), and Needham (1957). The great advantage claimed for this method is that stained bacilli can be detected using a much lower magnification than with the usual Ziehl-Neelsen method. Considerable time is saved in examining smears and larger areas can be searched. The method has not been widely employed for two reasons. In the first place, the light source must be very bright and many of the optical systems described previously have only supplied sufficient light if the equipment was used in a darkened room. Secondly, some workers (Ritterhoff and Bowman, 1945; Kuster, 1939; Holm and Plum, 1943) consider that false positive results can be obtained, since some smears may contain small naturally fluorescent particles which can be confused with bacilli. Equipment for fluorescence microscopy that can be used in normal daylight has been in use at the Tuberculosis Chemotherapy Centre, Madras, for over two years. When it was first introduced, a comparison between this method and the conventional Ziehl-Neelsen method was undertaken to test their relative sensitivities, and to see whether fluorescence microscopy yielded false positive results. The results of this comparison are described

Anti-transpirant activity in xylem sap from flooded tomato (Lycopersicon esculentum Mill.) plants is not due to pH-mediated redistributions of root- or shoot-sourced ABA

In flooded soils, the rapid effects of decreasing oxygen availability on root metabolic activity are likely to generate many potential chemical signals that may impact on stomatal apertures. Detached leaf transpiration tests showed that filtered xylem sap, collected at realistic flow rates from plants flooded for 2 h and 4 h, contained one or more factors that reduced stomatal apertures. The closure could not be attributed to increased root output of the glucose ester of abscisic acid (ABA-GE), since concentrations and deliveries of ABA conjugates were unaffected by soil flooding. Although xylem sap collected from the shoot base of detopped flooded plants became more alkaline within 2 h of flooding, this rapid pH change of 0.5 units did not alter partitioning of root-sourced ABA sufficiently to prompt a transient increase in xylem ABA delivery. More shoot-sourced ABA was detected in the xylem when excised petiole sections were perfused with pH 7 buffer, compared with pH 6 buffer. Sap collected from the fifth oldest leaf of 'intact' well-drained plants and plants flooded for 3 h was more alkaline, by ~0.4 pH units, than sap collected from the shoot base. Accordingly, xylem [ABA] was increased 2-fold in sap collected from the fifth oldest petiole compared with the shoot base of flooded plants. However, water loss from transpiring, detached leaves was not reduced when the pH of the feeding solution containing 3-h-flooded [ABA] was increased from 6.7 to 7.1 Thus, the extent of the pH-mediated, shoot-sourced ABA redistribution was not sufficient to raise xylem [ABA] to physiologically active levels. Using a detached epidermis bioassay, significant non-ABA anti-transpirant activity was also detected in xylem sap collected at intervals during the first 24 h of soil flooding

The MaTE Tool—Enabling Engaged Scholars at a Regional University

Providing institutionally recognized evidence of community engaged scholarship has long been problematic for engaged scholars when applying for recognition through promotion or probation pathways. To combat this, the University of Wollongong [in New South Wales, Australia] developed an online tool for use by engaged scholars to track and measure their engagement activities in a consistent and institutionally recognized form. This article outlines the process that was undertaken to develop the online system for measuring and tracking engagement (the MaTE tool). It outlines the initial recognition of the key issues arising from a comprehensive review of the literature; the drafting process undertaken to develop a prototype for the tool; and the interview stage and subsequent re-drafting process and finalization of the tool. The article concludes with a consideration of future directions for the tool and its further implementation at the university

Rezyklierte Phosphordünger - was die Branche davon hält

Phosphor in Abwässern muss ab 2026 rückgewonnen werden. Was halten Landwirte und andere Düngeexperten davon