372 research outputs found
Wales and the United Kingdom: a territorial constitutional policy drive
The Welsh Labour government has developed a distinctive brand of territorial constitutional policy in the UK context. The product of a strongly devolutionist government with a care for union, it reinforces the importance of autochthonous development in substate governance, reflects an adverse state of power relations in a famously uncodified constitution, and, framed by ongoing turbulence, provides an alternative vision of the UK territorial constitution at large. Building up Wales as a politically progressive polity, and promoting federal-type ideas of subsidiarity and shared governance in the union, are major threads. Grounded in the notion of popular sovereignties in a multipolar polity, and stressing the need for continued consent to and reform of the union, the approach represents a profound and difficult constitutional challenge. Wales as a substate polity remains a work in process, with largescale devolution of justice high on the policy agenda, while competing pressures of centralism and interest in independence inform an increasingly fluid territorial debate that sees the establishment of a new Constitutional Commission. A sustained exercise of constitutional voice, and, shown with Brexit and a muscular unionism of the Conservative government at Westminster, the struggle to be heard, characterizes the Welsh Government effort at the UK level
Champagne Flutes and Brandy Snifters: Modelling Protostellar Outflow-Cloud Chemical Interfaces
A rich variety of molecular species has now been observed towards hot cores
in star forming regions and in the interstellar medium. An increasing body of
evidence from millimetre interferometers suggests that many of these form at
the interfaces between protostellar outflows and their natal molecular clouds.
However, current models have remained unable to explain the origin of the
observational bias towards wide-angled "brandy snifter" shaped outflows over
narrower "champagne flute" shapes in carbon monoxide imaging. Furthermore,
these wide-angled systems exhibit unusually high abundances of the molecular
ion HCO. We present results from a chemo-dynamic model of such regions
where a rich chemistry arises naturally as a result of turbulent mixing between
cold, dense molecular gas and the hot, ionized outflow material. The injecta
drives a rich and rapid ion-neutral chemistry in qualitative and quantitative
agreement with the observations. The observational bias towards wide-angled
outflows is explained naturally by the geometry-dependent ion injection rate
causing rapid dissociation of CO in the younger systems.Comment: Accepted to MNRAS. 12 pages, 8 Figure
Quasars from the 7C Survey - I:sample selection and radio maps
We describe the selection of candidate radio-loud quasars obtained by
cross-matching radio source positions from the low-frequency (151 MHz) 7C
survey with optical positions from five pairs of EO POSS-I plates scanned with
the Cambridge Automatic Plate-measuring Machine (APM). The sky region studied
is centred at RA 10 h 28 m, Dec +41 and covers 0.057 sr. We present VLA
observations of the quasar candidates, and tabulate various properties derived
from the radio maps. We discuss the selection criteria of the resulting `7CQ'
sample of radio-loud quasars. The 70 confirmed quasars, and some fraction of
the 36 unconfirmed candidates, constitute a filtered sample with the following
selection criteria: 151-MHz flux density S151 > 100 mJy; POSS-I E-plate
magnitude E approx R < 20; and POSS-I colour (O - E) < 1.8; the effective area
of the survey drops significantly below S151 approx 200 mJy. We argue that the
colour criterion excludes few if any quasars, but note, on the basis of recent
work by Willott et al. (1998b), that the E magnitude limit probably excludes
more than 50 per cent of the radio-loud quasars.Comment: Latex, 30 pages. Accepted by MNRA
Deep optical imaging of the field of PC1643+4631A&B, I: Spatial distributions and the counts of faint galaxies
We present deep optical images of the PC1643+4631 field obtained at the WHT.
This field contains two quasars at redshifts z=3.79 & 3.83 and a cosmic
microwave background (CMB) decrement detected with the Ryle Telescope. The
images are in U,G,V,R and I filters, and are complete to 25th magnitude in R
and G and to 25.5 in U. The isophotal galaxy counts are consistent with the
results of Metcalde et al. (1996), Hogg et al. (1997), and others. We find an
excess of robust high-redshift Ly-break galaxy candidates with 25.0<R<25.5
compared with the mean number found in the fields studied by Steidel et al. -we
expect 7 but find 16 - but we do not find that the galaxies are concentrated in
the direction of the CMB decrement. However, we are still not sure of the
distance to the system causing the CMB decrement. We have also used our images
to compare the commonly used object-finding algorithms of FOCAS and SExtractor:
we find FOCAS the more efficient at detecting faint objects and the better at
dealing with composite objects, whereas SExtractor's morphological
classification is more reliable, especially for faint objects near the
resolution limit. More generally, we have also compared the flux lost using
isophotal apertures on a real image with that on a noise-only image: recovery
of artificial galaxies from the noise-only image significantly overestimates
the flux lost from the galaxies, and we find that the corrections made using
this technique suffer a systematic error of some 0.4 magnitudes.Comment: 17 pages, 40 figures, submitted to MNRAS, 1 large figure avaliable at
ftp://ftp.mrao.cam.ac.uk:/pub/PC1643/paper1.figure18.p
Achieving Very High PV Penetration
This article argues that optimally deployed intermittency solutions could affordably transform solar power generation into the firm power delivery system modern economies require, thereby enabling very high solar penetration and the displacement conventional power generation. The optimal deployment of these high‐penetration enabling solutions imply the existence of a healthy power grid, and therefore imply a central role for utilities and grid operators. This article also argues that a value‐based electricity compensation mechanism, recognizing the multifaceted, penetration‐dependent value and cost of solar energy, and capable of shaping consumption patterns to optimally match resource and demand, would be an effective vehicle to enable high solar penetration and deliver affordable firm power generation
Identification of the active site of legumain links it to caspases, clostripain and gingipains in a new clan of cysteine endopeptidases
AbstractWe show by site-directed mutagenesis that the catalytic residues of mammalian legumain, a recently discovered lysosomal asparaginycysteine endopeptidase, form a catalytic dyad in the motif His-Gly-spacer-Ala-Cys. We note that the same motif is present in the caspases, aspartate-specific endopeptidases central to the process of apoptosis in animal cells, and also in the families of clostripain and gingipain which are arginyl/lysyl endopeptidases of pathogenic bacteria. We propose that the four families have similar protein folds, are evolutionarily related in clan CD, and have common characteristics including substrate specificities dominated by the interactions of the S1 subsite
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The challenges of using satellite data sets to assess historical land use change and associated greenhouse gas emissions: a case study of three Indonesian provinces
Advances in satellite remote sensing and the wealth of earth observation (EO) data now available have improved efforts toward determining and quantifying historical land use and land cover (LULC) change. Satellite imagery can overcome the absence of accurate records of historical land use; however, the variability observed in the case study regions demonstrates a number of current challenges.
Differences in spatial coverage, resolution and land cover classification can lead to challenges in analyzing historical data sets to estimate LULC change and associated GHG emissions. This paper demonstrates the calculation of LULC change from three existing, open-source data sets to show how this can lead to significant variation in estimates of GHG emissions related to differences in land classification methodologies, EO input data and period of investigation. This article focuses on selected regions of Indonesia, where quantifying land use change is important for GHG assessments of agricultural commodities and for evidencing progress against corporate and government deforestation commitments.
Given the significance of GHG emissions arising from LULC change and the increasing need for emissions monitoring, this research highlights a need for consensus building to develop consistency in historical and future LULC change estimates. This paper concludes with a set of recommendations for improvements to ensure consistent LULC mapping
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