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The present study was conducted in dairy herds were MRSA presence was previously demonstrated with the aim to (i) evaluate the prevalence of MRSA intra-mammary infections (IMI) and (ii) identify the specific environmental contamination. MRSA IMI's were detected at low prevalence (less than 5%), except for one herd where it reached the 24,8%. The circulating MRSA genotypes were different for each herd and in two herds two different genotypes were found with one of them predominant. Four and 11 out of 18 cows, among those with MRSA IMI, were positive for nasal and udder skin swabs, respectively. The environmental analyses showed that milking parlor was systematically contaminated in different sites as well as the young calves mangers and buckets, whereas the heifers pens and mangers were not. Thus, in MRSA positive herds, especially milkers and personnel to young calves should be considered at risk of occupational infections.

This paper presents a detailed petrochemical and minerochemical study on some Roman granite columns from the archaeological site of Uthina. An ancient roman city located about 30km SW from Tunis (Tunisia), near the village of Oudhna. Some of the sampled columns show a very similar macroscopic aspect to the pinkish-grey granites outcropping in the ancient quarry area of Capo Testa, in northern Sardinia (Italy). In order to provide a comparison between the archaeological samples and the granite of these quarries a detailed geo-archeological survey and sampling of the Capicciolu, Li Petri Taddati, Cala Romana, Cava Grande del Torre "loci" (Capo Testa peninsula) and of the two La Marmorata Island "loci" were carried out. The results of the analyses showed that three of the sampled columns (these pinkish-grey in colour) have a strong resemblance with the samples of La Marmorata quarries. This demonstrates that, during the II-III centuries AD, the granite of North Sardinia quarries had a diffusion beyond the regional limits, confirming the identification of several granite artifacts discovered in monuments of the ancient Rome and in some other cities of the North Africa provinces.

Il lavoro affronta lo studio archeometrico sistematico dei reperti in marmo bianco rinvenuti nell'area di scavo italo - tunisina del sito archeologico di Uthina (Tunisia). Dai risultati delle analisi minero-petrografiche, chimiche e isotopiche e con l'impiego di una banca dati di riferimento, costruita di recente utilizzando un gran numero di campioni sia di marmi provenienti da antiche cave sia di manufatti di attribuzione certa, è stato possibile individuare le cave di provenienza di ciascun reperto indagato. L'integrazione di queste informazioni con quelle di natura più strettamente storico-archeologica ha consentito un'interpretazione più focalizzata nella ricostruzione di importanti aspetti della vita quotidiana della comunità che nel corso dei secoli ha popolato questa prestigiosa colonia romana del Nord Africa tra cui: i rapporti con il territorio occupato, le relazioni con altre genti, gli scambi di manufatti e materie prime secondo le principali rotte commerciali seguite nel Mediterraneo in epoca romana. I risultati dell'indagine archeometrica sono serviti inoltre ad attribuire i singoli frammenti a comuni manufatti scultorei ed elementi architettonici, favorendo così l'opera del restauratore.

The paper describes the results of chemical and mineralogical characterisation studies and mineral processing trials conducted for assessing the feasibility of beneficiating an alkaline basalt containing peridotite nodules cropping out in the Pozzomaggiore area in NW Sardinia. A detailed mineralogic study, carried out by means of XRF, XRD and electron probe microanalyses, showed the nodules to be composed essentially of dominant olivine, ortho- and clinopyroxenes with accessory spinel. Quantitative mineralogic composition was determined by pure mass balance method and a modified version developed during this work. Mineral processing tests performed using grinding as well as classification and magnetic separation processes, obtained a nodule-free basalt product and an olivine and pyroxene concentrate suitable in the production of abrasives.

Conservazione e valorizzazione del patrimonio culturale scientifico dell'Università, diffusione della cultura storico-scientifica anche presso il grande pubblico e utilizzo della storia della scienza per una didattica che non vuole presentare uno schematico insieme di "verità" ma mira a fornire agli studenti gli strumenti per elaborare una propria sintesi culturale: questi i tre intenti che animano e si intrecciano all'interno di un progetto di ricerca del Gruppo di Storia della Fisica dell'Università di Pavia.

The development of studies concerning volcanism-related deposits renewed the interest in porphyry-type and epithermal bodies in Sardinia. Calc-alkaline volcanics of Oligo-Miocene age widely outcrop in the western half of this island where a series of field surveys showed that metal - bearing hydrothermal alterations are widespread in the Tertiary subvolcanic rocks. A Cu-Au-Mo-bearing porphyry-system, of "diorite model" type, has been discovered in the area of Siliqua (southern Sardinia) and an exploration programme is going to be developed. In ore outcrops, characterized by abundant sulphide minerals, weathering-related reactions cause acid mine and rock drainage (AMD/ARD) having the potential to produce large volumes of low-pH sulphate-bearing waters during oxidation and leaching of mineralized materials. These solutions may generate many different geochemical phenomena especially concerning metal mobility and subseguent precipitation outside mining environments. Environmental concerns, associated with the starring of open-pit operations, ore removal activities and waste accumulation, in the local warm and semiarid climate, are largely related to possible contamination of the surrounding soils and freshwater bodies. Other risks are related to some possible exploration works, especially exploratory trenches and excavations. Furthermore some controls on the surrounding water bodies and soils have already shown high heavy metal contents.

The coal petrology, major, minor and trace elements composition was determined in the "I vena" seams of the Sulcis coalfield, southwest Sardinia - Italy. This work has focused particularly on chemical analysis of coal and coal ash by XRF, AAS and ICP-OES, in order to draw up elemental concentration pattern and elemental affinity profiles. Elemental concentration is rather uniform in the seams examined. Most elements are associated with the mineral matter and there concentration increase with increasing of the ash content of coal. The elements B. Cd, Ce, La, and Pb are associated with the organic portion of the coal. Some elements (B. Ba. Co, Cu. Li, P, Sr. V) show both a mineral and organic affinity.