998 resultados para Trace form


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Issues of authenticity and identity are particularly significant in cities where social and cultural change is shaping active transformation of its urban fabric and structure in the post-war condition. In search of sustainable future, Iraqi cities are stretched between the two ends of the spectrum, authentic quarters with its traditional fabric and modern districts with their global sense of living. This paper interrogates the reciprocal influences, distinct qualities and sustainable performance of both authentic and modern quarters of Erbil, the
capital of the Iraqi province of Kurdistan, as factors in shaping sustainable urban forms for Iraqi cities. In doing so, the paper, firstly, seeks to highlight the urban identity as an effective factor in relation to sustainable urban form. Secondly, the city of Erbil in Iraq has been chosen as a field study, due to its regional, social, political and historical role in the region. Thirdly, the study emphasises the dynamic activities and performance of residential projects according to rational sustainable criteria. The research concludes that urban identity and the sense of place in traditional and historical places should inform design strategies in order to achieve a more sustainable urban context.

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We present Hubble Space Telescope (HST) rest-frame ultraviolet imaging of the host galaxies of 16 hydrogen-poor superluminous supernovae (SLSNe), including 11 events from the Pan-STARRS Medium Deep Survey. Taking advantage of the superb angular resolution of HST, we characterize the galaxies' morphological properties, sizes, and star formation rate (SFR) densities. We determine the supernova (SN) locations within the host galaxies through precise astrometric matching and measure physical and host-normalized offsets as well as the SN positions within the cumulative distribution of UV light pixel brightness. We find that the host galaxies of H-poor SLSNe are irregular, compact dwarf galaxies, with a median half-light radius of just 0.9 kpc. The UV-derived SFR densities are high ([Sigma(SFR)] similar or equal to 0.1M(circle dot) yr(-1) kpc(-1)), suggesting that SLSNe form in overdense environments. Their locations trace the UV light of their host galaxies, with a distribution intermediate between that of long-duration gamma-ray bursts (LGRBs; which are strongly clustered on the brightest regions of their hosts) and a uniform distribution (characteristic of normal core-collapse SNe), though cannot be statistically distinguished from either with the current sample size. Taken together, this strengthens the picture that SLSN progenitors require different conditions than those of ordinary core-collapse SNe to form and that they explode in broadly similar galaxies as do LGRBs. If the tendency for SLSNe to be less clustered on the brightest regions than are LGRBs is confirmed by a larger sample, this would indicate a different, potentially lower-mass progenitor for SLSNe than LRGBs.

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Carbon and nitrogen stable isotope analysis (SIA) has identified the terrestrial subsidy of freshwater food-webs but relies on different 13C fractionation in aquatic and terrestrial primary producers. However dissolved inorganic carbon (DIC) is partly comprised of 13C depleted respiration of terrestrial C and ‘old’ C derived from weathering of catchment geology. SIA thus fails to differentiate between the contribution of old and recently fixed terrestrial C. DIC in alkaline lakes is partially derived from weathering of 14C-free carbonaceous bedrock This
yields an artificial age offset leading samples to appear significantly older than their actual age. As such, 14C can be used as a biomarker to identify the proportion of autochthonous C in the food-web. With terrestrial C inputs likely to increase, the origin and utilisation of ‘old’ or ‘recent’ allochthonous C in the food-web can also be determined. Stable isotopes and 14C were measured for biota, particulate organic matter (POM), DIC and dissolved organic carbon (DOC) from Lough Erne, Northern Ireland, a humic but alkaline lake. High winter δ15N values in calanoid zooplankton (δ15N =24‰) relative to phytoplankton and POM (δ15N =6‰ and 12‰ respectively) may reflect several microbial trophic levels between terrestrial C and calanoids. Furthermore winter calanoid 14C ages are consistent with DOC from inflowing rivers (87 and 75 years BP respectively) but not phytoplankton (355 years BP). Summer calanoid δ13N, δ15N and 14C (312 years BP) indicate greater reliance on phytoplankton. There is also temporal and spatial variation in DIC, DOC and POM C isotopes.

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Globally lakes bury and remineralise significant quantities of terrestrial C, and the associated flux of terrestrial C strongly influences their functioning. Changing deposition chemistry, land use and climate induced impacts on hydrology will affect soil biogeochemistry and terrestrial C export1 and hence lake ecology with potential feedbacks for regional and global C cycling. C and nitrogen stable isotope analysis (SIA) has identified the terrestrial subsidy of freshwater food webs. The approach relies on different 13C fractionation in aquatic and terrestrial primary producers, but also that inorganic C demands of aquatic primary producers are partly met by 13C depleted C from respiration of terrestrial C, and ‘old’ C derived from weathering of catchment geology. SIA thus fails to differentiate between the contributions of old and recently fixed terrestrial C. Natural abundance 14C can be used as an additional biomarker to untangle riverine food webs2 where aquatic and terrestrial δ 13C overlap, but may also be valuable for examining the age and origin of C in the lake. Primary production in lakes is based on dissolved inorganic C (DIC). DIC in alkaline lakes is partially derived from weathering of carbonaceous bedrock, a proportion of which is14C-free. The low 14C activity yields an artificial age offset leading samples to appear hundreds to thousands of years older than their actual age. As such, 14C can be used to identify the proportion of autochthonous C in the food-web. With terrestrial C inputs likely to increase, the origin and utilisation of ‘fossil’ or ‘recent’ allochthonous C in the food-web can also be determined. Stable isotopes and 14C were measured for biota, particulate organic matter (POM), DIC and dissolved organic carbon (DOC) from Lough Erne, Northern Ireland, a humic alkaline lake. Temporal and spatial variation was evident in DIC, DOC and POM C isotopes with implications for the fluctuation in terrestrial export processes. Ramped pyrolysis of lake surface sediment indicates the burial of two C components. 14C activity (507 ± 30 BP) of sediment combusted at 400˚C was consistent with algal values and younger than bulk sediment values (1097 ± 30 BP). The sample was subsequently combusted at 850˚C, yielding 14C values (1471 ± 30 BP) older than the bulk sediment age, suggesting that fossil terrestrial carbon is also buried in the sediment. Stable isotopes in the food web indicate that terrestrial organic C is also utilised by lake organisms. High winter δ 15N values in calanoid zooplankton (δ 15N = 24%¸) relative to phytoplankton and POM (δ 15N = 6h and 12h respectively) may reflect several microbial trophic levels between terrestrial C and calanoids. Furthermore winter calanoid 14C ages are consistent with DOC from an inflowing river (75 ± 24 BP), not phytoplankton (367 ± 70 BP). Summer calanoid δ 13C, δ 15N and 14C (345 ± 80 BP) indicate greater reliance on phytoplankton.

1 Monteith, D.T et al., (2007) Dissolved organic carbon trends resulting from changes in atmospheric deposition chemistry. Nature, 450:537-535

2 Caraco, N., et al.,(2010) Millennial-aged organic carbon subsidies to a modern river food web. Ecology,91: 2385-2393.

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DNA from members of a three-generation pedigree of Irish origin, displaying an autosomal dominant simplex form of epidermolysis bullosa of the epidermolytic, simplex, or Koebner variety (EBS2), was analyzed for linkage with a set of markers derived from the long arm of chromosome 1. Two-point analysis revealed positive lod scores for five of these markers, AT3 (Z = 2.107, theta = 0), APOA2 (Z = 1.939, theta = 0.15), D1S66 (Z = 1.204, theta = 0), D1S13 (Z = 1.026, theta = 0.15), and D1S65 (Z = 0.329, theta = 0.15). Multilocus analysis, incorporating the markers D1S19, D1S16, D1S13, APOA2, D1S66, AT3, and D1S65, resulted in a lod score of 3 maximizing at AT3. These data strongly support previous tentative indications of linkage between EBS2 and genetic markers on the long arm of chromosome 1.

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This workshop draws on an emerging collaborative body of research by Lovett, Morrow and McClean that aims to understand architecture and its processes as a form of pedagogical practice: a civic pedagogy.

Architectural education can be valued not only as a process that delivers architecture-specific skills and knowledges, but also as a process that transforms people into critically active contributors to society. We are keen to examine how and where those skills are developed in architectural education and trace their existence and/or application within practice. We intend to examine whether some architectural and spatial practices are intrinsically pedagogical in their nature and how the level of involvement of clients, users and communities can mimic the project-based learning of architectural education – in particularly in the context of ‘live project learning’

1. This workshop begins with a brief discussion paper from Morrow that sets out the arguments behind why and how architecture can be understood as pedagogy. It will do so by presenting firstly the relationship between architectural practice and pedagogy, drawing out both contemporary and historical examples of architecture and architects acting pedagogically. It will also consider some other forms of creative practice that explicitly frame themselves pedagogically, and focus on participatory approaches in architectural practice that overlap with inclusive and live pedagogies, concluding with a draft and tentative abstracted pedagogical framework for architectural practice.

2. Lovett will examine practices of architectural operation that have a pedagogical approach, or which recognise within themselves an educational subtext/current. He is most interested in a 'liveness' beyond the 'Architectural Education' of university institutions. The presentation will question the scope for both spatial empowerment / agency and a greater understanding and awareness of the value of good design when operating as architects with participant-clients younger than 18, older than 25 or across varied parts of society. Positing that the learning might be greatest when there are no prescribed 'Learning Outcomes' and that such work might depend on risk-taking and playfulness, the presentation will be a curated showcase drawing on his own ongoing work.

Both brief presentations will inform the basis of the workshop’s discussion which hopes to draw on participants views and expereinces to enrich the research process. The intention is that the overall workshop will lead to a call for contributors and respondents to a forthcoming publication on ‘Architecture as Pedagogy’.