96 research outputs found

    Effect of a veterinary antibiotic and manure amendment on the structure and function of soil microbial community

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    This thesis was aimed at studying the sorption of the antibiotic tetracycline (Tc), at two different concentrations (100 and 500 mg kg-1), on two soils (a clay soil and a sandy soil). In particular, the effects on the microbial structural and functional diversity and on the resistance level were investigated in microcosms on three consecutive dates (2, 7, 60 d) since single treatment with manure and additional Tc. Microbial counts, PFLA, CLPP, FDA analysis were concordant in pointing out a short time detrimental effect on the microbial structure and function after the Tc treatment at the higher rate. The DGGE fingerprinting investigation on 16S-rRNA gene fragments and resistance gene level were based on a separate experiment with three consecutive manure and Tc additions to soil. A single treatment was effective to modify the whole bacterial community of clay soil, whereas additional treatments were necessary in the sandy soil. Manure increased the abundance of mobile genetic elements (intI1, trfA, korB) and sul genes related to Tc resistance in soil. The genes tetA, tetQ, tetW were affected mostly by manure than Tc addition. Tc showed a transient effect on microbial structure after single treatment, whereas manure increased the bacterial diversity and resistance in soil after repeated treatments. The results were consistent with the bioavailability of Tc in soil

    Definizione degli elementi conoscitivi e progettuali per l'istituzione di aree marine protette

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    La sensibilizzazione alla tutela ambientale, fatto prioritario per la creazione di parchi, riserve od oasi naturali, deve inevitabilmente passare attraverso l'acquisizione di tutte le componenti del sistema, macro e microscopiche, e del loro ruolo nel contesto ambientale. Ci riferiamo qui a quel processo cognitivo che va sotto la denominazione di "analisi strutturale o formale degli ecosistemi", un metodo che rappresenta l'opposto all'approccio naturalistico-descrittivo che negli anni passati ha avuto così grande spazio e che è stato il massimo responsabile della diffusione di una visione statica dell'ambiente che fatichiamo a toglierci di dosso

    seasonal variation of essential oil in rosmarinus officinalis leaves in sardinia

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    Rosmarinus officinalis L. is an aromatic plant belonging to the Lamiaceae family widely distributed in the Mediterranean area. The interest on this species is related to the multiple uses of the plant as a food ingredient, in the pharmaceutical and cosmetic industries. The chemical composition of essential oil (EO) from 5 accessions of R. officinalis L., collected monthly through a full year in Sardinia, has been studied by gas chromatography (GC) and GC-mass spectrometry technique. The EO ranged from 0.29% to 0.89%. The qualitative determinations revealed the presence of 27 compounds belonging to 6 chemical groups (hydrocarbon monoterpene, alcohols, aldehydes, ketones, esters, hydrocarbon sesquiterpene). Overall the GC-flame ionization detector analysis showed the presence of 7 major compounds: α-pinene (26%-28%), camphene (5%-8%), 1,8-cineole (15%-25%), borneol (5%-11%), camphor (3%-12%), verbenone (6%-15%), and bornyl acetate (4%-7%). Chromatographic data were also subjected to a chemometric approach that evidenced discrimination of the samples according to the site of collection

    On the circalittoral benthic communities in the Asinara Marine Park = Sui popolamenti circalitorali dell'Isola dell'Asinara

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    This work reports the results of various surveys made in the North Weslern part of Asinara National Park. It was oriented to the description of deep benthic communities. A conspicuous number of rare species and biogeographically interesting populations for the Mediterranean Sea are present in this area, in particular coralligenous formation are present in typical form as well as in enclave and platlorms

    Detecting Social Interactions in Working Environments Through Sensing Technologies

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    The knowledge about social ties among humans is important to optimize several aspects concerning networking in mobile social networks. Generally, ties among people are detected on the base of proximity of people. We discuss here how ties concerning colleagues in an office can be detected by leveraging on a number of sociological markers like co-activity, proximity, speech activity and similarity of locations visited. We present the results from two data gathering campaigns located in Italy and Spain.Ministerio de Economía y Competitividad TIN2013-46801-C4-1-RJunta de Andalucía TIC-805

    Geographical variation of the chemical composition in essential oils extracted from Sardinian Salvia verbenaca

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    : Salvia verbenaca is a perennial herbaceous plant well appreciated as medicinal herb which can be found in Mediterranean area, Europe, Africa and Asia. In this study, S. verbenaca flowers and leaves were collected in six different geographical areas of Sardinia (Italy). Information about the variation of the chemical composition of plants grown in different locations were obtained from gas chromatography analysis of the extracted essential oils. Gas chromatography analysis detected 33 compounds, which have been grouped in oxygenated monoterpenes, monoterpene hydrocarbons, sesquiterpenes and other compounds. The chemical composition of each group resulted significantly affected by sampling site in terms of geography and altitude. Concerning the geographical distribution of the detected chemicals, sesquiterpenes were found in considerable amount in three localities, monoterpenes hydrocarbons in two and other compounds were predominant only in one site. Regarding the altitude level, monoterpenes, sesquiterpenes and other compounds were predominant, respectively, at medium and medium-high altitude

    Morphometric relationships and annual gonad index of the edible Sea urchin <i>Paracentrotus lividus</i> from North Western Sardinia = Relazioni morfometriche e indice gonadico annuale del riccio di mare commestibile <i>Paracentrotus lividus</i> nel nord ovest Sardegna

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    Weight/diameter, weight/height and height/diameter morphometric relationships were calculated for a shallow rocky Paracentrotus lividus population sampled monthly near Alghero (Italy) from November 2004 to October 2005. Gonad index (GI) of the sea urchins was also evaluated. Statistical analyses showed significant differences of GI between 2 distinct periods of the year: late fall-winter and spring-late summer

    Profiling of the Bioactive Compounds in Flowers, Leaves and Roots of Vinca sardoa

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    Vinca sardoa (Stern) Pignatti (Apocynaceae) is largely distributed in Sardinia where it is considered a typical endemism. Since the plant is used in traditional folk medicine, the aim of the present work was to identify and quantify the polyphenolic metabolites, due to the well-known importance of polyphenolic compounds, as well as to evaluate antioxidant activity in different parts of the plant. The compounds were identified and determined in the methanol extracts of leaves, flowers, and roots by developing different LC-MS/MS methods. The obtained data show that leaves possess the highest amount of polyphenols, in particular quinic acid (3401 mg/100 g), chlorogenic acid (1082 mg/100 g), caffeoylquinic acid isomer 1 (190 mg/100 g), and robinin (633 mg/100 g). Likewise, antioxidant tests showed that leaves possess the main radical scavenging activities in both ABTS (49.19 ± 3.41 μg/mL, 30.88 ± 3.04 μg/mL at time zero and after 50 min, respectively) and DPPH assays (223.97 ± 30.81 μg/mL, 109.52 ± 12.89 μg/mL at time zero and after 30 min, respectively). Taking into account that leaves differed most from flowers and roots in the content of caffeoylquinic acid and chlorogenic acid, of which antioxidant properties are widely recognized, it is reasonable to assume that these two compounds are involved in the differences described. The relationship between the high polyphenolic content and interesting antioxidant activities, justifies its use in ethnobotany and may be suggest a use of this specie, after removal of the alkaloid fraction, in the pharmaceutical, phytotherapy, and cosmetic industries

    Caratterizzazione fisiografica, geomorfologica e bionomica della <i>Rias</i> di Santa Teresa di Gallura: Sardegna nord-orientale = Physiographic, geomorphological and bionomic characterization of the Santa Teresa di Gallura <i>Rias</i> (N.E. Sardinia)

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    An underwater survey in the Rias of S. Teresa di Gallura was made to characterize the benthic environment by integrating three methods: Side Scan Sonar, ROV, SCUBA diving. The main bionomic features at different depths were described and mapped. The presence of Savalia savaglia, a rare Mediterranean species contributed to enhance the environmental value of the study area

    Small-scale perturbation on soft bottom macrozoobenthos after mechanical cleaning operations in a Central-Western Mediterranean lagoon

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    1 - Sardinia Island (Italy), even if relatively small, has over 100 lagoons totalling some 12,000 ha. Yet their potential yield remain often unexpressed because they are subjected to environmental stress and degradation. As far as benthic communities are concerned, one of the main disturbances is certainly the accumulation of shell detritus, which progressively modifies the way benthic organisms interact with the sediment. 2 - An experimental dredging study was therefore performed in the Calich lagoon (NW Sardinia), due to its particular interest for fishing activities and potential semi-intensive mollusc culture. Changes in benthic community structure were examined in two areas of the lagoon by analysing both the demographic profile of several abundant species and the features of sedimentary matrix immediately after the cleaning operations and seven months later. Data obtained were compared with those collected in undisturbed areas of the lagoon. This allowed us to evaluate the effects of dredging operations on the benthic assemblages unaffected by natural temporal shifts of the system. 3 - Univariate and multivariate analyses indicated a strong relationship between macrofaunal community structure and intensity of the cleaning activities. At the dredged sites benthic fauna was not depleted but did exhibit higher diversity and evenness indexes than at the undisturbed sites. This seemed to be a consequence of decrease in the density of some abundant species at the dredged sites. Furthermore, a general reduction of total organic content was observed in the upper sediment layer. Lastly, the cleaning method employed is discussed in relation to its potential for impacting the benthos
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