51 research outputs found
Predictions for ASKAP Neutral Hydrogen Surveys
The Australian Square Kilometer Array Pathfinder (ASKAP) will revolutionise
our knowledge of gas-rich galaxies in the Universe. Here we present predictions
for two proposed extragalactic ASKAP neutral hydrogen (HI) emission-line
surveys, based on semi-analytic models applied to cosmological N-body
simulations. The ASKAP HI All-Sky Survey, known as WALLABY, is a shallow 3 Pi
survey (z = 0 - 0.26) which will probe the mass and dynamics of over 600,000
galaxies. A much deeper small-area HI survey, called DINGO, aims to trace the
evolution of HI from z = 0 - 0.43, a cosmological volume of 40 million Mpc^3,
detecting potentially 100,000 galaxies. The high-sensitivity 30 antenna ASKAP
core (diameter ~2 km) will provide an angular resolution of 30 arcsec (at z=0).
Our simulations show that the majority of galaxies detected in WALLABY (87.5%)
will be resolved. About 5000 galaxies will be well resolved, i.e. more than
five beams (2.5 arcmin) across the major axis, enabling kinematic studies of
their gaseous disks. This number would rise to 160,000 galaxies if all 36 ASKAP
antennas could be used; the additional six antennas provide baselines up to 6
km, resulting in an angular resolution of 10 arcsec. For DINGO this increased
resolution is highly desirable to minimise source confusion; reducing confusion
rates from a maximum of 10% of sources at the survey edge to 3%. We estimate
that the sources detected by WALLABY and DINGO will span four orders of
magnitude in total halo mass (from 10^{11} to 10^{15} Msol) and nearly seven
orders of magnitude in stellar mass (from 10^{5} to 10^{12} Msol), allowing us
to investigate the process of galaxy formation across the last four billion
years.Comment: 21 pages, accepted for publication in MNRAS, minor updates to
published version and fixed links. Movies and images available at
http://ict.icrar.org/store/Movies/Duffy12c
Artist career in music: stakeholders requirement report
No abstract available.publishe
The clustered nature of star formation. Pre--main-sequence clusters in the star-forming region NGC 602/N90 in the Small Magellanic Cloud
Located at the tip of the wing of the Small Magellanic Cloud (SMC), the
star-forming region NGC602/N90 is characterized by the HII nebular ring N90 and
the young cluster of pre--main-sequence (PMS) and early-type main sequence
stars NGC602. We present a thorough cluster analysis of the stellar sample
identified with HST/ACS camera in the region. We show that apart from the
central cluster, low-mass PMS stars are congregated in thirteen additional
small compact sub-clusters at the periphery of NGC602. We find that the spatial
distribution of the PMS stars is bimodal, with an unusually large fraction
(~60%) of the total population being clustered, while the remaining is
diffusely distributed in the inter-cluster area. From the corresponding
color-magnitude diagrams we disentangle an age-difference of ~2.5Myr between
NGC602 and the compact sub-clusters which appear younger. The diffuse PMS
population appears to host stars as old as those in NGC602. Almost all detected
PMS sub-clusters appear to be centrally concentrated. When the complete PMS
stellar sample, including both clustered and diffused stars, is considered in
our cluster analysis, it appears as a single centrally concentrated stellar
agglomeration, covering the whole central area of the region. Considering also
the hot massive stars of the system, we find evidence that this agglomeration
is hierarchically structured. Based on our findings we propose a scenario,
according to which the region NGC602/N90 experiences an active clustered star
formation for the last ~5Myr. The central cluster NGC602 was formed first and
rapidly started dissolving into its immediate ambient environment, possibly
ejecting also massive stars found away from its center. Star formation
continued in sub-clusters of a larger stellar agglomeration, introducing an
age-spread of the order of 2.5Myr among the PMS populations.Comment: Accepted for publication by The Astrophysical Journal. 14 pages, 11
figures, 1 table, 2-columns forma
Diet composition and activity level of at risk and metabolically healthy obese American adults.
OBJECTIVE: Obesity often clusters with other major cardiovascular disease risk factors, yet a subset of the obese appears to be protected from these risks. Two obesity phenotypes are described, (i) metabolically healthy obese, broadly defined as body mass index (BMI) ≥ 30 kg/m(2) and favorable levels of blood pressure, lipids, and glucose; and (ii) at risk obese, BMI ≥ 30 with unfavorable levels of these risk factors. More than 30% of obese American adults are metabolically healthy. Diet and activity determinants of obesity phenotypes are unclear. We hypothesized that metabolically healthy obese have more favorable behavioral factors, including less adverse diet composition and higher activity levels than at risk obese in the multi-ethnic group of 775 obese American adults ages 40-59 years from the International Population Study on Macro/Micronutrients and Blood Pressure (INTERMAP) cohort. DESIGN AND METHODS: In gender-stratified analyses, mean values for diet composition and activity behavior variables, adjusted for age, race, and education, were compared between metabolically healthy and at risk obese. RESULTS: Nearly one in five (149/775 or 19%) of obese American INTERMAP participants were classified as metabolically healthy obese. Diet composition and most activity behaviors were similar between obesity phenotypes, although metabolically healthy obese women reported higher sleep duration than at risk obese women. CONCLUSIONS: These results do not support hypotheses that diet composition and/or physical activity account for the absence of cardiometabolic abnormalities in metabolically healthy obese
Improved large-area forest increment information in Europe through harmonisation of National Forest Inventories
14 Pág.Consistent knowledge about the increment in European forests gained amplified importance in European policies and decision processes related to forest-based bioeconomy, carbon sequestration, sustainable forest management and environmental changes. Until now, large-area increment information from European countries was lacking international comparability. In this study we present a harmonisation framework in accordance with the principles and the approach established for the harmonisation of National Forest Inventories (NFIs) in Europe. 11 European NFIs, representing a broad range of increment measurement and estimation methods, developed unified reference definitions and methods that were subsequently implemented to provide harmonised increment estimates by NUTS regions (Nomenclature of territorial units for statistics of the European Union), main forest types and tree species groups, and to rate the impact of harmonisation measures. The main emphasis was on gross annual increment (GAI), however, also annual natural losses (ANL) and net annual increment (NAI) were estimated. The data from the latest available NFI cycles were processed. The participating countries represent a forest area of about 130 million ha, and 82% of the European Unions’ (EU) forest area, respectively. The increments were estimated in terms of volume (m³ year−1, m³ ha−1 year−1) and above-ground biomass (t year−1, t ha−1 year−1). The harmonised GAI volume estimates deviate in a range of +12.3% to −26.5% from the estimates according to the national definitions and estimation methods. Within the study area, the harmonised estimates show a considerable range over the NUTS regions for GAI, from 0.6 to 12.3 m³ ha−1 year−1, and 0.8–6.4 t ha−1 year−1, of volume and above-ground biomass, respectively. The largest increment estimates are found in Central Europe and gradually decrease towards the North, South, West and East. In most countries coniferous forests show larger increment estimates per hectare than broadleaved forests while mixed forests are at an intermediate level. However, in some instances, the differences were small or mixed forests revealed the largest increment estimates. The most important tree species groups in the study area are Pinus spp. and Picea spp., contributing 29% and 26% of the estimated total GAI volume, respectively. The shares of the prevalent broadleaved species are smaller with contributions of 9%, 7% and 6% by Quercus spp., Fagus sylvatica and Betula spp. The results underline the importance of harmonisation in international forest statistics. Looking ahead, harmonised large-area increment estimation is pivotal for accurate monitoring and evidence-based policy decisions in the changing context of future forest ecosystems dynamics, management strategies and wood availability.This research was supported by the Specific Contracts No. 20 and 21 “Use of National Forest Inventories data to harmonise and improve the current knowledge on forest increment in Europe” in the context of the “Framework contract for the provision of forest data and services in support to the JRC activities and applications on forest resources (Contract Number 934340)” of the Joint Research Centre of the European Commission.Peer reviewe
In COVID-19 Health Messaging, Loss Framing Increases Anxiety with Little-to-No Concomitant Benefits: Experimental Evidence from 84 Countries
The COVID-19 pandemic (and its aftermath) highlights a critical need to communicate health information effectively to the global public. Given that subtle differences in information framing can have meaningful effects on behavior, behavioral science research highlights a pressing question: Is it more effective to frame COVID-19 health messages in terms of potential losses (e.g., "If you do not practice these steps, you can endanger yourself and others") or potential gains (e.g., "If you practice these steps, you can protect yourself and others")? Collecting data in 48 languages from 15,929 participants in 84 countries, we experimentally tested the effects of message framing on COVID-19-related judgments, intentions, and feelings. Loss- (vs. gain-) framed messages increased self-reported anxiety among participants cross-nationally with little-to-no impact on policy attitudes, behavioral intentions, or information seeking relevant to pandemic risks. These results were consistent across 84 countries, three variations of the message framing wording, and 560 data processing and analytic choices. Thus, results provide an empirical answer to a global communication question and highlight the emotional toll of loss-framed messages. Critically, this work demonstrates the importance of considering unintended affective consequences when evaluating nudge-style interventions
The psychological science accelerator’s COVID-19 rapid-response dataset
In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data
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