ABSTRACT
The Trans-Atlantic Research and Development Interchange on Sustainability Workshop (TARDIS) is a meeting on scientific topics related to sustainability. The 2019 workshop theme was "On the Role of Uncertainty in Managing the Earth for Global Sustainability." This paper presents the perspectives on this topic derived from talks and discussions at the 2019 TARDIS workshop. There are four kinds of uncertainties encountered in sustainability ranging from clear enough futures to true surprises. The current state-of-the-art in assessing and mitigating these uncertainties is discussed.
ABSTRACT
Binarity is believed to dramatically affect the history and geometry of mass loss in AGB and post-AGB stars, but observational evidence of binarity is sorely lacking. As part of a project to search for hot binary companions to cool AGB stars using the GALEX archive, we discovered a late-M star, Y Gem, to be a source of strong and variable UV and X-ray emission. Here we report UV spectroscopic observations of Y Gem obtained with the Hubble Space Telescope that show strong flickering in the UV continuum on time-scales of â² 20 s, characteristic of an active accretion disk. Several UV lines with P-Cygni-type profiles from species such as Si IV and C IV are also observed, with emission and absorption features that are red- and blue-shifted by velocities of ~500 km s-1 from the systemic velocity. Our model for these (and previous) observations is that material from the primary star is gravitationally captured by a companion, producing a hot accretion disk. The latter powers a fast outflow that produces blue-shifted features due to absorption of UV continuum emited by the disk, whereas the red-shifted emission features arise in heated infalling material from the primary. The outflow velocities support a previous inference by Sahai et al. (2015) that Y Gem's companion is a low-mass main-sequence star. Blackbody fitting of the UV continuum implies an accretion luminosity of about 13 Lâ, and thus a mass-accretion rate > 5 × 10-7Mâ yr-1; we infer that Roche lobe overflow is the most likely binary accretion mode for Y Gem.
ABSTRACT
Two epidemiological surveys of New Zealand adolescents are reported. The prevalence of asthma was 7.5 percent in Rotorua and 7.9 percent in Wairoa. Additional questions asked in Wairoa identified 18.2 percent of subjects who had experienced wheeze but had not been labelled "asthma". The association of active asthma with nasal obstruction was confirmed. Wheeze which had not been labelled asthma was associated with the combination of subject's own and maternal cigarette smoking. The use of asthma medication was associated with easier geographic and socio-economic access to medical care, as well as with asthma activity.
Subject(s)
Asthma/epidemiology , Respiratory Sounds/epidemiology , Adolescent , Adult , Age Factors , Airway Obstruction/etiology , Asthma/complications , Asthma/physiopathology , Child , Child, Preschool , Growth , Humans , Infant , Infant, Newborn , Middle Aged , New Zealand , Smoking , Socioeconomic FactorsABSTRACT
The outline organisation of a health survey of a secondary school is presented. The aims of the survey were primarilary to provide population data on rheumatic fever in a high incidence area, and to further knowledge of the distribution of risk factors for coronary heart disease in New Zealand adolescents. Ninety-six and a half percent coverage of the target group was achieved; non-responders were characterised from hospital and school records as being predominantly rural with greater early childhood hospital experience than respondents. The sample was considered to be representative of the adolescent population of the area.