30,128 research outputs found
Plasters in the cellars of the Visconti Castle in Pavia. Physico-Chemical characterization
No full textAn archaeometric investigation on plaster samples taken from the cellars of the Visconti Castle in Pavia has brought out the existence of several layers and colour films of various periods. The oldest plaster spread over the masonry is formed with three main layers. Above them, one film of bluish-black colour can be found on the arcs and on the bearing walls. On this black layer, a white film of calcitic composition, containing also apatite fragments, was spread. These ancient materials were subsequently covered in more recent times with plasters having different compositions and textures.
In the present paper the properties of the three main plaster layers and those of the black film are reported in detail. The thermal behaviour of these materials was studied by means of differential thermal analysis and thermogravimetric analysis. The study was completed with scanning electron microscopy, microprobe analysis and X-ray diffraction on powders.
The results obtained provide interesting clues for advancing reasonable hypotheses both on the methods adopted in ancient building yards, and on the techniques for the production of the pigments employed
Population trend and distribution of mountain (Lepus timidus) and brown hares (Lepus europaeus) in Central Alps (N-Italy, 1980–2020)
No full textMountainous regions are very vulnerable to climate changes, as they experience higher temperature increases than the surrounding environments. A general movement of species toward higher altitudes, in search of suitable sites, is being observed. In the case of the Italian Alps, an expansion of the brown hare (Lepus europaeus) is possible within the zones occupied by the mountain hare (Lepus timidus), which frequents higher altitudes. The risk is an increase in the hybridization and a contraction of the mountain hare’s range. In this study, we analyzed the hunting bags (weighted by the number of active hunters each year) of brown and mountain hares from the period of 1980–2020, in the province of Sondrio (Central Alps) in northern Lombardy (N-Italy), with the aim of (i) highlighting any population trends in relation to climate change,
(ii) identifying altitudinal changes in the distribution of the two species over the years, (iii) identifying the environmental variables that influence the distribution of the two species, and (iv) creating suitability maps in the study area. To study population trends, the hunting bag data were corrected by dividing the number of hare shot by the number of active hunters in that year. For both species, no population trends were found between 1980 and 2020. Weather variables do not seem to have influenced population trends. No significant trends in the altitudinal distribution of the two species were observed over the period investigated. The results indicate that the two species select different altitudes, with the exception of the belt between 1600 and 1800 m a.s.l. Both species select meadows
Maria Bersani
No full textLa voce illustra la biografia e l'apporto letterario dato da Maria Bersani alla letteratura per l'infanziaThe headword explains the biography and the contribution of the author Maria Bersani to the children's literatur
Planning low-impact tourist paths within a Site of COmmunity Importance through the optimisation of biological and logistic criteria
No full textA leading goal in the management of protected areas is to promote a balanced coexistence between wildlife and people. Although this target may be achieved by limiting human activities through buffer zones and restricted areas, a more rigorous approach can be based on optimisation models founded on quantitative and transparent scientific methodologies. In this paper, a decision model is proposed, for the first time, for planning low-impact tourist paths within a European Union Site of Community Importance. The proposed methodology seeks to plan optimised paths based on a virtual landscape built on both biological and logistic criteria. Our model consists of four steps: (1) choice of biological and logistic constraints; (2) selection of biological and logistic factors; (3) use of fuzzy scoring to standardize and weight criteria and (4) application of least-cost modelling to the virtual landscape resulting from previous steps.
We identified three optimised routes for new tourist paths which have the least possible impact on existing biodiversity (habitats, plant and animal species), meeting logistic criteria as well. The proposed approach also allows the impacts of suggested paths to be estimated quantitatively thereby allowing comparison with existent paths. Proposed paths, based on optimisation, perform considerably well; furthermore, we were able to propose the decommissioning of eight existing paths that have high impacts on biodiversity. This work not only proposes a framework for planning low-impact tourist paths within protected areas, but also purports the idea that, through the use of proper optimisation models, a satisfactory balance between nature and human activities is achievable
Un progetto di educazione ambientale per le scuole elementari di Pavia: Giochiamo con la Terra.
No full textIntonaci e malte nella cripta di San Felice: studio mineralogico, petrografico e termico.
No full textI lavori di ripristino della chiesa del monastero di S. Felice hanno richiesto, durante la loro fase di pianificazione, l’analisi dei materiali utilizzati nella costruzione dell’edificio. In particolare hanno destato notevole interesse le malte e gli intonaci provenienti dalla cripta ed è di questi materiali che è stata realizzata una caratterizzazione mineralogico-petrografica e termica presso le strutture dell’Università di Pavia.
I campioni analizzati provengono da differenti ambienti della cripta: prelievi sono stati effettuati sia dalle pareti e dalle volte che dalle arche alloggiate nelle tre nicchie meridionali.
Lo studio di tali materiali, effettuato con differenti tecniche analitiche, ha permesso di delineare le caratteristiche composizionali e tessiturali principali. Alcune correlazioni tra gli strati tecnici che compongono gli intonaci consentono di ricostruire una possibile successione temporale di interventi all’interno dei locali della cripta. I materiali provenienti dalle arche mostrano una particolare attenzione posta nella realizzazione; la loro funzione era quella di decorare l’architettura marmorea simulando intarsi preziosi
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