650 research outputs found
MANAGEMENT PLANS AND WEB-GIS SOFTWARE APPLICATIONS AS ACTIVE AND DYNAMIC TOOLS TO CONSERVE AND VALORIZE HISTORIC PUBLIC GARDENS
Abstract. Historic gardens are artefacts that evolve in a continuous and unavoidable way, and, at the same time, they are heritage and cultural sites that need to be conserved: the recognition of this dual nature motivates us to seek for new approaches to their management issues. Whilst it is necessary to follow site mutations and valorize its features while dynamically changes the appearance of the garden and the needs of the society, at the same time it is fundamental that an appropriate strategic plan sets a target for the garden, a midmid-long term vision, in order to preserve botanic and documentary value and maintain historic and artistic significance. The paper analyzes historical sources, surveys, thematic maps and interpretations to study historic public gardens, considering complexity and vulnerability of the components an d issues involved in historic gardens and consequent multidisciplinary approach. In order to identify conservation and management criteria it underlines analysis and evaluation of the environmental, architectural, land scape and perceptive features of the historic garden and its surroundings, demonstrating the importance to study the site historic stratification and the site context in order to define preservation goals to prevent decay, to mitigate impacts, to set up maintenance programs and management plans. The aim of this essay is also to highlight the role of GIS and WebGIS applications – targeted at public administrations – that integrate the spatial component (topographic map, ortophoto, physical plans, cadastral maps) and databases about botanic inventories and conservation and valorization treatments of historic public of public gardens.</p
The Ecosystem Approach to Fisheries: Issues, Terminology, Principles, Institutional Foundations, Implementation and Outlook
Ecosystems are complex and dynamic natural units that produce goods and services beyond those of benefit to fisheries. Because fisheries have a direct impact on the ecosystem, which is also impacted by other human activities, they need to be managed in an ecosystem context. The meaning of the terms 'ecosystem management', 'ecosystem based management', 'ecosystem approach to fisheries'(EAF), etc., are still not universally defined and progressively evolving. The justification of EAF is evident in the characteristics of an exploited ecosystem and the impacts resulting from fisheries and other activities. The rich set of international agreements of relevance to EAF contains a large number of principles and conceptual objectives. Both provide a fundamental guidance and a significant challenge for the implementation of EAF. The available international instruments also provide the institutional foundations for EAF. The FAO Code of Conduct for Responsible Fisheries is particularly important in this respect and contains provisions for practically all aspects of the approach. One major difficulty in defining EAF lies precisely in turning the available concepts and principles into operational objectives from which an EAF management plan would more easily be developed. The paper discusses these together with the types of action needed to achieve them. Experience in EAF implementation is still limited but some issues are already apparent, e.g. in added complexity, insufficient capacity, slow implementation, need for a pragmatic approach, etc. It is argued, in conclusion, that the future of EAF and fisheries depends on the way in which the two fundamental concepts of fisheries management and ecosystem management, and their respective stakeholders, will join efforts or collide
THE GEO-REFERENCED XIX CENTURY CARTOGRAPHY: AN ANALYSIS TOOL AND A PROJECT REFERENCE FOR THE PRESERVATION AND MANAGEMENT OF BUILT AND LANDSCAPE HERITAGE
Abstract. Considering built and landscape heritage, the paper demonstrates how it is necessary to conserve the historic stratification and to define new compatible plans and uses, identifying the ways to mitigate alteration impacts, requalify degraded areas, enhance natural, historic and cultural values, improve documentary and educational options, and manage new tasks and opportunities. Particularly, the historic complexity of built and landscape heritage, and the level of permanence can be recognized and evaluated by comparing multi-temporal historic and current maps, and surveying the present situation in order to define preservation strategies.Innovative tools (open source map registry, open source GIS data management) support the critical analysis of the maps, the representation of historic stratification, the evaluation of conservation levels, and the definition of heritage reuse and management. Moreover, innovative applications based on advanced Virtual Hub, when used to publish historical maps as Open Data (GEOPAN ATL@S APP), allow a larger public of non-expert users (tourists, citizens, bikers, students, etc.) to access the extraordinary richness of the historical map contents, and navigate across urban landscapes. Such APPs are thus becoming instruments of awareness with a strong pro-active capacity to stimulate new design plans encompassing local cultural identity and rediscovering traces of the past.</p
Corrected Mulliken Charges for Small Molecules
A quantum mechanical correction is applied to the Mulliken
atomic charges in order to fit them to the calculated dipole
moment. This correction is obtained from the Charge - Charge
flux - Overlap model (CCFO) for the interpretation of infrared
intensities. Values of corrected Mulliken charges are calculated
using different basis sets for the HF, H20, NH3, CH4, LiF, LiCI
and NaCI molecules. The corrected charges are compared with
atomic charges obtained from other partitioning schemes. Our
results reveal that the corrected Mulliken charge shows an excellent numerical stability when the basis set becomes more extended. It also gives a better description of the charge separation in predominantly ionic molecules. Finally, the Mulliken charge seems to reflect more adequately intramolecular interactions when corrected as above
DIGITAL TWIN TO MONITOR, UNDERSTAND AND PRESERVE THE COMPLEXITY OF MULTI-SCALE NATURAL, AGRICULTURAL, DESIGNED LANDSCAPES AND ARCHITECTURE: BIODIVERSITY CONSERVATION, TRANSFORMATION AND DECLINE AT VILLA ARCONATI SITE AT CASTELLAZZO OF BOLLATE (MI)
Search for low instability strip variables in the young open cluster NGC 2516
In this paper we revise and complete the photometric survey of the
instability strip of the southern open cluster NGC 2516 published by Antonello
and Mantegazza (1986). No variable stars with amplitudes larger than
were found. However by means of an accurate analysis based on a new statistical
method two groups of small amplitude variables have been disentangled: one with
periods (probably Scuti stars) and one with periods
. The position in the HR diagram and the apparent time-scale may
suggest that the stars of the second group belong to a recently discovered new
class of variables, named Dor variables. They certainly deserve
further study. We also present a comparison between the results of the
photometric survey and the available pointed ROSAT observations of this
cluster.Comment: 7 pages, 2 ps figures. Accepted for P.A.S.
Synthesis of calcium oxalate trihydrate: new data by vibrational spectroscopy and synchrotron X-ray diffraction
Calcium oxalate is found in nature in three different crystalline states determined by the number of H2O in the unit formula (whewellite CaC2O4\ub7H2O, COM; weddellite CaC2O4\ub7(2 + x)H2O, COD and caoxite CaC2O4\ub73H2O, COT). The properties of these materials are relevant in the field of biomedicine, cultural heritage and mineralogy. In two previous papers, we have used X-ray diffraction and vibrational spectroscopy (infrared and Raman) to derive information on crystal and molecular structures of COM and COD. In this paper, we complete the synthesis and analysis on the third form, COT, and present a comparative study of the data collected from the three crystalline states. The experiments clearly highlight the role played by the H2O molecules linked within the structure by different kinds of hydrogen bonds. The vibrational assignment of the infrared and Raman bands are critically proposed. The fact relevant for the work in biomedicine, cultural heritage and crystallography is that a simple examination of the spectra allows quickly to determine the chemical nature of the material in an unknown sample even in a minute quantity or in awkward experimental conditions
Stabilization of linear carbon structures in a solid Ag nanoparticle assembly
Linear sp carbon nanostructures are gathering interest for the physical
properties of one-dimensional (1D) systems. At present, the main obstacle to
the synthesis and study of these systems is their instability. Here we present
a simple method to obtain a solid system where linear sp chains (i.e. polyynes)
in a silver nanoparticle assembly display a long term stability at ambient
conditions. The presence and the behavior of linear carbon is investigated by
Surface Enhanced Raman Scattering (SERS) exploiting the plasmon resonance of
the silver nanoparticles assembly. This model system opens the possibility to
investigate an intriguing form of carbon nanostructures
Gamma Doradus Stars: Defining a New Class of Pulsating Variables
In this paper we describe a new class of pulsating stars, the prototype of
which is the bright, early, F-type dwarf, Gamma Doradus. These stars typically
have between 1 and 5 periods ranging from 0.4 to 3 days with photometric
amplitudes up to 0.1 in Johnson V. The mechanism for these observed variations
is high-order, low-degree, non-radial, gravity-mode pulsation. Gamma Doradus
stars exhibit variability on a time scale that is an order of magnitude slower
than Delta Scuti stars. They may offer additional insight into stellar physics
when they are better understood (e.g., they may represent the cool portion of
an "iron opacity instability strip" currently formed by the Beta Cephei stars,
the SPB stars, and the subdwarf B stars; they may also offer insight into the
presence of g-modes in solar-like stars).Comment: 15 pages, 1 ps figure. Accepted for publication in PAS
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