Microbial mats of the Tswaing impact crater: results of a South African exobiology expedition and implications for the search for biological molecules on Mars

We describe microbial mats from the Tswaing impact crater in South Africa. The mats provide insights into the unique biological characteristics of impact craters and can help strategies for the search for biomolecules on Mars

Survey Tools for Measuring Research or Evidence‐Based Practice Constructs in Dietetics: A Narrative Review

Background: Exact quantification of research conducted by dietitians and tracking the effectiveness of interventions or training programs to increase either evidence-based practice (EBP) or research behaviours have been hampered by the variety of tools used to measure these constructs. Methods: In this narrative review, we identified and classified the various tools previously used to measure constructs related to research and/or EBP in the dietetics profession, and to summarise estimates of the constructs measured. Results: We identified and classified 15 scored tools that had been used at least once in the dietetics profession and extracted tool parameter estimates from 22 resulting papers. We also identified six unscored tools and three qualitative studies. The most frequent constructs measured were attitudes and behaviours. Very few tools measured objective knowledge (skills). No objective measures of research outputs were identified. Several tools were closely related to one another. Conclusions: Even when tools were used across multiple papers, reporting method varied making comparisons difficult. This review should encourage future researchers to utilise existing tools when possible, and encourage the development or adaptation and testing of tools that fill identified gaps. The constructs measured by the tools identified may also provide a starting point for the development of educational interventions aiming to increase research or EBP skills among dietitians. Only by using consistent tools will the dietetics profession be able to track the progress in increasing research conduct and EBP implementation over time

Limited Maternal Gene Flow Amongst Elk in the Greater Yellowstone Ecosystem Revealed by Mitochondrial DNA

We quantified maternal patterns of population genetic structure to help understand gene flow among elk (Cervus elaphus) populations across the Greater Yellowstone Ecosystem. We sequenced 596 base pairs of the mitochondrial (mt)DNA control region of 407 elk from nine populations. Our analysis revealed high mtDNA diversity within populations including 12 haplotypes per population on average, and a mean haplotype diversity (i.e., gene diversity) of 0.84. The FST from mtDNA was high (mean FST = 0.162; P = 0.0001) compared to FST for nuclear microsatellites data (FST = 0.006, P = 0.125), which suggested relatively low female movement among populations, perhaps due to female philopatry. Genetic distance (mtDNA pair-wise FST) was not significantly correlated with geographic (Euclidean) distance between populations (Mantel’s r = 0.274, P = 0.168). The lack of isolation-by-distance and large genetic distance between geographically close populations (< 65 km) suggest that maternal gene flow is reduced by certain landscape features (e.g., large, non-forested valleys with roads), which is important for understanding and modeling landscape connectivity and related processes

Adoption of dynamic simulation for an energy performance rating tool for Korean residential buildings : EDEM-SAMSUNG

Currently, there is a high emphasis on reducing the energy consumption and carbon emissions of buildings worldwide. Korea is facing an emerging issue of energy savings in buildings in perspective of new green economic policy. In this context, various policy measures including the energy efficiency ratings for buildings are being implemented for domestic and non-domestic buildings. In practice, design teams tend to prefer easy to use assessment tools to optimise energy performance and carbon ratings while they are concerned about calculation accuracy and the accurate representation of the dynamics involved associated with the characteristics of Korean residential buildings. This paper presents an assessment tool, named ‘EDEM-Samsung’ that aims to address these challenges for Korean residential apartments, which often encounter complex design issues. EDEM-Samsung is a tool that enables users to make rapid decisions identifying the effect of design parameter changes on energy and carbon ratings with an effective user interface and without compromising accuracy. This paper describes the architecture and functionalities of the tool, and the advantages offered to Korean designers

Chiropteran Enamel Structure

We have examined sectioned and whole teeth of Hipposideros diadema in order to provide a baseline description of bat enamel at electron microscope level. Intact and worn surfaces of whole teeth from representatives of all superfamilies of the suborder Microchiroptera, representatives of the suborder Megachiroptera, and the Ditjimanka fossil tooth have been surveyed. Whole chiropteran teeth lend themselves well to non-destructive SEM examination; all except Dobsonia sp. showing evidence of prismatic structure at the outer surface. The majority of prisms in chiropteran enamel are horse-shoe shaped becoming rounded and complete only towards the outer enamel surface. Prism packing is typically Pattern 3 near the enamel-dentine junction and Pattern 2 where the enamel is sufficiently thick. A major feature is the consistent presence of a minor boundary plane ( seam ) at the open end of horse-shoe shaped prisms. Enamel tubules were found at the enamel-dentine junction of a number of species and consistently at the outer enamel surface of one, Macroglossus minimus. Further examination of embedded material is planned in order to quantify prism shape, prism packing and the disposition of tubules in chiropteran enamel

Salts and Radiation Products on the Surface of Europa

The surface of Europa could contain the compositional imprint of an underlying interior ocean, but competing hypotheses differ over whether spectral observations from the Galileo spacecraft show the signature of ocean evaporates or simply surface radiation products unrelated to the interior. Using adaptive optics at the W. M. Keck Observatory, we have obtained spatially resolved spectra of most of the disk of Europa at a spectral resolution ~40 times higher than seen by the Galileo spacecraft. These spectra show a previously undetected distinct signature of magnesium sulfate salts on Europa, but the magnesium sulfate is confined to the trailing hemisphere and spatially correlated with the presence of radiation products like sulfuric acid and SO_2. On the leading, less irradiated, hemisphere, our observations rule out the presence of many of the proposed sulfate salts, but do show the presence of distorted water ice bands. Based on the association of the potential MgSO_4 detection on the trailing side with other radiation products, we conclude that MgSO_4 is also a radiation product, rather than a constituent of a Europa ocean brine. Based on ocean chemistry models, we hypothesize that, prior to irradiation, magnesium is primarily in the form of MgCl_2, and we predict that NaCl and KCl are even more abundant, and, in fact, dominate the non-ice component of the leading hemisphere. We propose observational tests of this new hypothesis

Dear Wife : the Civil War letters of Chester K. Leach

Occasional paper (University of Vermont. Center for Research on Vermont) ; no. 20

Observational constraints on the distribution and temperature dependence of H_2O_2 on the surface of Europa

We use Keck NIRSPEC to investigate the geographic distribution of hydrogen peroxide, a potentially biologically important oxidant, on the surface of Europa. Contrary to expectation, we see the highest abundances at low latitudes, potentially correlated with geologically young chaos terrain. We also use NASA IRTF SpeX spectra of Europa before and after eclipse to investigate the extent to which temperature controls equilibrium hydrogen peroxide concentrations on the surface. During eclipse, Europa's surface temperature falls 10-20 K. If temperature were a significant control on peroxide concentrations, then the hydrogen peroxide band strengths should be different pre- and post-eclipse. Ultimately, these investigations will help further our understanding of the surface, and perhaps subsurface, composition of Europa