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La disponibilità a pagare e le preferenze dei turisti per i siti del Parco Geominerario della Sardegna: il caso di Porto Flavia
Get PDFQuesto lavoro presenta alcuni risultati di uno studio di valutazione contingente, condotto al fine di stimare il valore turistico di Porto Flavia: un sito fra i più interessanti del Parco Geominerario recentemente istituito in Sardegna sotto il patrocinio dell’UNESCO. Dopo aver discusso il ruolo che adeguate politiche di gestione dei beni culturali ed ambientali possono assumere per garantire uno sviluppo turistico sostenibile, descriviamo le principali caratteristiche del metodo, la struttura dell’indagine ed i dati ottenuti. L’analisi dei dati si concentra sulla stima della disponibilità a pagare e del flusso turistico potenziale. Sono identificati possibili obiettivi d’intervento per la valorizzazione del percorso esistente ed una gamma di prezzi per diverse opzioni di offerta turistica
The properties of some goodness-of-fit tests
Get PDFThe properties of Pearson’s goodness-of-fit test, as used in density forecast evaluation, income distribution analysis and elsewhere, are analysed. The components-of-chi-squared or “Pearson analog” tests of Anderson (1994) are shown to be less generally applicable than was originally claimed. For the case of equiprobable classes, where the general components tests remain valid, a Monte Carlo study shows that tests directed towards skewness and kurtosis may have low power, due to differences between the class boundaries and the intersection points of the distributions being compared. The power of individual component tests can be increased by the use of nonequiprobable classes
How far do we trade intermediate inputs?
Get PDFWe look at determinants of intermediates inputs imports focusing on the role of distance as a direct measure of the costs involved in spreading a production process across different economies. We consider imports to two countries: Italy, whose competitive advantage is still hinged in the traditional sectors, and Germany, strongly specialized in skilled and capital intensive activities; in two sectors, footwear and PCs; in two periods end of the 80s and end of the 90s. Delocalization of stages of that part of the production which serves the domestic market to a foreign country is a costly activity at least because of the transport costs from re-importing goods home. The evidence of falling off imports with distance captures exactly how transport costs can offset other cost advantages from the use of cheaper resources. Our results would suggest this is not the case in all sectors, at least not in the production of computers and their parts. Imports of intermediates inputs for electronic components are not a clear indication of activities outsourced, delocalized with the aim of reducing costs. Other characteristics of trade patterns and of their production technology will have to investigated in order to understand the map of their production and their movements across borders, i.e. the determinants of the fragmentation of their production process
Come cambia la governance in Europa. Lo sviluppo territoriale attraverso reti cooperative
Get PDFSebbene alla base delle ricerche che negli ultimi decenni
hanno affrontato il problema di come disegnare interventi socioeconomici
‘radicati’ in un contesto vi siano motivazioni diverse (da considerazioni
di sviluppo ed efficienza a questioni democraticonormative),
tutte evidenziano la necessità di ricercare un nuovo rapporto
tra politica, mercato e società.
Il presente contributo si inserisce all’interno degli ultimi sviluppi
di questi dibattiti, e si articola in tre parti: nella prima viene sinteticamente
riportato in che modo diverse correnti teoriche abbiano affrontato
la questione, con la finalità di evidenziare come le loro posizioni
siano più lontane nella teoria che non nella pratica4. Nella seconda
parte le categorie ed i concetti presi in esame vengono collegati al dibattito
intorno al processo di istituzionalizzazione dell’Unione Europea
(UE). Nella terza parte vengono presentate, sulla base dell’analisi
di due casi empirici della Politica Regionale dell’UE, alcune considerazioni
conclusive sul funzionamento di network cooperativi orizzontali
e verticali che indirettamente rispondano al quesito di partenza,
ossia come disegnare interventi di sviluppo che stimolino gli attori sociali
alla cooperazione
Ridefinizione biostratigrafica e geocronologica delle unità formazionali neogeniche della Sardegna centrale (Italia)
Get PDFRecent, detailed geological and stratigraphic surveys of a large area of the Marmilla region (central Sardinia) have made it possible to reconsider the lithobiostratigraphic
characteristics of the formal and informal units in the literature on the Cenozoic (Late Oligocene – Neogene) which have been in use up to now. Extension of the research to adjoining lands, including Alta Marmilla, Alto Oristanese, Sinis–Planargia, Barigadu, Baronie and Sarcidano, has also made it possible to perform an overall analysis of the entire Cenozoic basin of central Sardinia and, finally, to make significant comparisons with the coeval successions outcropping in southern and northern Sardinia. In this preliminary note we then report on new data concerning the
biostratigraphic aspects of the successions considered, while eco-biostratigraphic data and the depositional and synthemic arrangement, now at an advanced stage of definition, will be discussed in a later, more complete work. Some units in the literature are once again proposed, albeit with amendments, as suggested by the new regulations
governing the establishment of new formal depositional units and conservation of units in the literature, and with new geochronostratigraphic delimitations (e. g. the Gesturi
Formation). Other units change their hierarchical rank (e. g. the Marmilla Group), while for others it was not deemed useful to keep them (e. g. Marne di Ales), since they
might cause confusion. Most of the Formations, all of the Members and Groups are proposed in this work for the first time. The formation units outcropping in central
Sardinia’s Cenozioc basin are represented for the most part by a sedimentary and volcano-sedimentary succession several hundreds of metres thick, the age of which is included within the Chattian-Aquitanian passage and the Plio-Quaternary. These are sediments from silicoclastics to mixed carbonatic-silicoclastics, in some cases richly
fossiliferous, in which are inserted volcanic products from acid to intermediate-basic with a calcalkaline composition, the latter almost exclusively present starting from the
Aquitanian up to the Late Burdigalian, with the strongest concentration in deposits of Burdigalian age. As is the case in northern and southern Sardinia, central Sardinia’s
Miocene formations can be referred to three main sedimentary cycles recognized on the basis of heir litho-biostratigraphy and the analysis of associations of benthic macrofauna, which will be discussed in a specific article to be published shortly. The first Miocene sedimentary cycle evolved between the Chattian/Aquitanian limit and the Late Burdigalian (N6 Zone); the second cycle began in the Uppermost Burdigalian, in correspondence to the upper part of the Globigerinoides trilobus Zone (N7 Zone) and
closes in the Late Serravallian (G. siakensis Zone, G. siakensis-G. obliqua obliqua Subzone); finally, after a clear regression phase, in the Tortonian (or perhaps already
in the Uppermost Serravillian) the third cycle began and ended in the Early Messinian, in correspondence to the upper part of biostratigraphic N17a Zone. On the basis of a
comparative analysis of autochthonous benthic associations, especially those with molluscs, and of the textural characteristics of the sediments, the prevalent depositional
environment for the three cycles mentioned previously is that of a platform and secondly of a slope, but in some cases fluvio-lacustrine and deltaic. At the end of the third cycle there is a hiatus and/or erosion, or local continental sedimentation (Nuraghe Baboe Cabitza A n. Formation). A further marine sedimentary cycle locally (Sinis, Orosei) began and ends in the Lower Pliocene (Nuraghe Baboe Cabitza B n. Formation). In an overall biostratigraphic and geochronological frame, the comparison between the most important sedimentary, tectonic and volcanic occurrences in central Sardinia from the
Oligocene to the Pliocene and those which occurred in the north and south of the island are pointed out. From the paleogeographic standpoint, the deposits of the first Miocene sedimentary cycle are part of the autochthonous cover of the southern European continental margin; those of the second and third cycles are instead connected with the
aperture of the Balearic basin and the northern Tyrrhenian Sea; finally, the Early Pliocene marine succession is referred to the open of the southern Tyrrhenian basin, as
well as the widespread volcanic activity of prevalently basaltic alkaline nature (the «Plio-Pleistocene volcanic cycle») towards the end of the Messinian and in the Pliocene
Il bootstrap. Un'applicazione informatica per un problema di ricampionamento
Get PDFThe aim of this paper is to give a simple introduction to the bootstrap
techniques showing a basic computer algorithm. The algorithm displays, step
by step, how to determinate a bootstrap confidence interval
Research on the changes in the flora and vegetation cover on "Isola Rossa" of Trinità D'Agultu (Central-Northern Sardinia)
Get PDFThe Authors report the results of their survey carried out on the Isola Rossa of Trinità d'Agultu (Central Northern Sardinia). This survey covered a two-year period and shows that 13 species previously reported do not seem to occur in the island any longer where as 23 new records have been added. The flora, consisting of 40 entities, included numerous invasive and ruderal species which have to a large extent modified the composition, floristic distribution and vegetation cover of the island, the species which has played a major role in this modification being without doubt Lavatera arborea L. Details are also provided on the main plani formations on the island, in comparison with those previously reported
Le visite pastorali in quattro diocesi della Sardegna centro meridionale nel periodo 1651-1850. Spunti per una analisi statistica delle informazioni contenute nel libro delle cresime
Get PDFThe authors, in addition to underlining further possibilities for using the
ecclesiastical source Quinque Libri, explore data that is possible to extract from the
inventory of the book of confirmations. They do that with reference to four
dioceses of Central-South Sardinia. Such an exploration has led the authors to
understand how the book of confirmations, for the period before the Unity of Italy,
could be a useful support for demo-social surveys as well as a source of
information for studies concerning to the knowledge and the activities of Sardinian
bishops
Giuseppe Brotzu and the Discovery of Cephalosporins
Get PDFGiuseppe Brotzu (1895-1976), for over thirthy years Professor of Hygiene in the Medical Faculty and Rector
(1936-1945) of the University of Cagliari, was also superintendent of Public Health during the campaign for
the eradication of malaria in Sardinia.
As a scientist, his fame is due to the discovery of cephalosporins that he made in Cagliari, at the end of the 2nd World War. He isolated from the outfalls of a local sewage a microorganism, identified as Cephalosporium acremonium, whose cultures inhibited several important Gram negatives as Salmonella typhi and Brucella Melitensis.
Even if he was aware of the importance of his discovery, owing to the lack of facilities and financial support
he was unable to study further the activity of the fungus.
Thus, in the year 1946, after the publication of his results on the journal "Lavori dell'Istituto di Igiene di
Cagliari", he sent the fungus to the Laboratory of Pathology at Oxford University. Here Edward Abraham,
who had been part of Florey team in the study of penillin, succeeded in producing the Cephalosporin
antibiotics, one of the most important tool in the therapy of infectious diseases.
For his discoveries Brotzu was awarded in 1971 the honorary degree in Science by Oxford University
Patti Territoriali e specializzazione produttiva nel Mezzogiorno
Get PDFI patti territoriali rappresentano uno strumento della programmazione negoziata capace, nelle intenzioni, di cogliere le istanze provenienti dal territorio. Analizzando la composizione territoriale e la specializzazione settoriale dei patti operanti nelle regioni meridionali il lavoro si domanda in quale misura questo obiettivo sia stato conseguito. Sulla base di una prima analisi ancora parziale a causa dell'incompletezza dei dati disponibili, l'articolazione territoriale dei patti appare molto influenzata dalle sfere di competenza dei soggetti istituzionali promotori ma raramente riflette la geografia delle aree sistema presenti nel Mezzogiorno e le loro interdipendenze. Anche dal punto di vista della specializzazione settoriale i risultati dell'analisi suggeriscono che i sistemi produttivi locali meridionali hanno svolto un ruolo limitato nella determinazione della composizione settoriale degli investimenti previsti nei patti