4,810 research outputs found
Warm Cores around Regions of Low-Mass Star Formation
Warm cores (or hot corinos) around low-mass protostellar objects show a rich
chemistry with strong spatial variations. This chemistry is generally
attributed to the sublimation of icy mantles on dust grains initiated by the
warming effect of the stellar radiation. We have used a model of the chemistry
in warm cores in which the sublimation process is based on extensive laboratory
data; these data indicate that sublimation from mixed ices occurs in several
well-defined temperature bands. We have determined the position of these bands
for the slow warming by a solar-mass star. The resulting chemistry is dominated
by the sublimation process and by subsequent gas-phase reactions; strong
spatial and temporal variations in certain molecular species are found to
occur, and our results are, in general, consistent with observational results
for the well-studied source IRAS 16293-2422. The model used is similar to one
that describes the chemistry of hot cores. We infer that the chemistry of both
hot cores and warm cores may be described by the same model (suitably adjusted
for different physical parameters).Comment: 11 pages, 5 figures, 2 tables. Accepted by MNRA
Creative small settlements. Culture-based solutions for local sustainable development.
Culture can play a fundamental role in fostering sustainable patterns of urban and regional development. This is the message of the Global Report ‘Culture for Sustainable Urban Development’, which UNESCO has coordinated for the UN-HABITAT III Conference (Quito, October 2016). The Global Report shows that a promising culture-based vision of urban development is flourishing in different forms in several cities across the world. Even small and medium settlements located at the periphery of large cities or within their metropolitan areas, and normally associated with marginalisation or deprivation, have the potential to fully utilise their cultural resources, in both tangible (urban and architectural heritage, cultural infrastructure, etc.) and intangible form (skills, knowledge, competencies). However these small settlements, and their respective communities, require different analytical tools in order to understand their complexity and ad hoc policies to manage their assets in sustainable forms.
This research report aims to show ways to understand culture and creativity in small settlements, by collecting a series of international case studies that form the backbone of the chapter 10 of the UNESCO Global Report on urban-rural linkages and titled 'Culture as a tool to achieve harmonious territorial development'. This can allow a wider dissemination of the theoretical underpinnings and the comparative findings of a research conducted during 2015 and 2016 by several research units all over the world
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