181 research outputs found
Towards a New International Law of the Atmosphere?
Inclusion of the topic ‘protection of the atmosphere’ in the current work programme of the UN International Law Commission (ILC) reflects the long overdue recognition of the fact that the scope of contemporary international law for the Earth’s atmosphere extends far beyond the traditional discipline of ‘air law’ as a synonym for airspace and air navigation law. Instead, the atmospheric commons are regulated by a ‘regime complex’ comprising a multitude of economic uses including global communications, pollutant emissions and diffusion, in different geographical sectors and vertical zones, in the face of different categories of risks, and addressed by a wide range of different transnational institutions. Following several earlier attempts at identifying crosscutting legal rules and principles in this field (by, inter alia, the International Law Association, the UN Environment Programme, and the Institut de Droit International), the ILC has now embarked on a new codification/restatement project led by Special Rapporteur Shinya Murase – albeit hamstrung by a highly restrictive ‘understanding’ imposed by the Commission in 2013. This article assesses the prospects and limitations of the initial ILC reports and debates in 2014 and 2015, and potential avenues for progress in the years to come
[Review of] International Climate Change Law. By Daniel Bodansky , Jutta Brunnée and Lavanya Rajamani . Oxford: Oxford University Press, 2017
The Dual Role of Outflows in Quenching Satellites of Low-Mass Hosts: NGC 3109
While dwarf galaxies observed in the field are overwhelmingly star-forming,
dwarf galaxies in environments as dense or denser than the Milky Way are
overwhelmingly quenched. In this paper, we explore quenching in the lower
density environment of the Small-Magellanic-Cloud-mass galaxy NGC 3109
(), which hosts two known dwarf
satellite galaxies (Antlia and Antlia B), both of which are HI deficient
compared to similar galaxies in the field and have recently stopped forming
stars. Using a new semi-analytic model in concert with the measured star
formation histories and gas masses of the two dwarf satellite galaxies, we show
that they could not have been quenched solely by direct ram pressure stripping
of their interstellar media, as is common in denser environments. Instead, we
find that separation of the satellites from pristine gas inflows, coupled with
stellar-feedback-driven outflows from the satellites (jointly referred to as
the starvation quenching model), can quench the satellites on timescales
consistent with their likely infall times into NGC 3109's halo. It is currently
believed that starvation is caused by "weak" ram pressure that prevents
low-density, weakly-bound gas from being accreted onto the dwarf satellite, but
cannot directly remove the denser interstellar medium. This suggests that
star-formation-driven outflows serve two purposes in quenching satellites in
low-mass environments: outflows from the host form a low-density circumgalactic
medium that cannot directly strip the interstellar media from its satellites,
but is sufficient to remove loosely-bound gaseous outflows from the dwarf
satellites driven by their own star formation.Comment: 20 pages and 2 appendices. To be submitted to MNRAS. Comments
welcome
Accelerated extracellular matrix turnover during exacerbations of COPD
BACKGROUND: Exacerbations of chronic obstructive pulmonary disease (COPD) contribute significantly to disease progression. However, the effect on tissue structure and turnover is not well described. There is an urgent clinical need for biomarkers of disease activity associated with disease progression. Extracellular matrix (ECM) turnover reflects activity in tissues and consequently assessment of ECM turnover may serve as biomarkers of disease activity. We hypothesized that the turnover of lung ECM proteins were altered during exacerbations of COPD. METHODS: 69 patients with COPD hospitalised for an exacerbation were recruited at admission and returned for a 4 weeks follow-up. Competitive ELISAs measuring circulating protein fragments in serum or plasma assessed the formation and degradation of collagen types III (Pro-C3 and C3M, respectively), IV (P4NP 7S and C4M, respectively), and VI (Pro-C6 and C6M, respectively), and degradation of elastin (ELM7 and EL-NE) and versican (VCANM). RESULTS: Circulating levels of C3M, C4M, C6M, ELM7, and EL-NE were elevated during an exacerbation of COPD as compared to follow-up (all P <0.0001), while VCANM levels were decreased (P <0.0001). Pro-C6 levels were decreased and P4NP 7S levels were elevated during exacerbation (P <0.0001). Pro-C3 levels were unchanged. At time of exacerbation, degradation/formation ratios were increased for collagen types III and VI and decreased for collagen type IV. CONCLUSIONS: Exacerbations of COPD resulted in elevated levels of circulating fragments of structural proteins, which may serve as markers of disease activity. This suggests that patients with COPD have accelerated ECM turnover during exacerbations which may be related to disease progression
SN~2012cg: Evidence for Interaction Between a Normal Type Ia Supernova and a Non-Degenerate Binary Companion
We report evidence for excess blue light from the Type Ia supernova SN 2012cg
at fifteen and sixteen days before maximum B-band brightness. The emission is
consistent with predictions for the impact of the supernova on a non-degenerate
binary companion. This is the first evidence for emission from a companion to a
SN Ia. Sixteen days before maximum light, the B-V color of SN 2012cg is 0.2 mag
bluer than for other normal SN~Ia. At later times, this supernova has a typical
SN Ia light curve, with extinction-corrected M_B = -19.62 +/- 0.02 mag and
Delta m_{15}(B) = 0.86 +/- 0.02. Our data set is extensive, with photometry in
7 filters from 5 independent sources. Early spectra also show the effects of
blue light, and high-velocity features are observed at early times. Near
maximum, the spectra are normal with a silicon velocity v_{Si} = -10,500$ km
s^{-1}. Comparing the early data with models by Kasen (2010) favors a
main-sequence companion of about 6 solar masses. It is possible that many other
SN Ia have main-sequence companions that have eluded detection because the
emission from the impact is fleeting and faint.Comment: accepted to Ap
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