Studio geo-idrologico della Sardegna Settentrionale: memoria 7.: idrogeologia e geochimica di alcune sorgenti dei dintorni di Ploaghe (SS)

È stato condotto uno studio idrogeologico ed idrogeochimico su un'area del Logudoro settentrionale, presso l'abitato di Ploaghe. A tal fine sono state prese in esame 14 sorgenti e, comparativamente, acque di scorrimento superficiale e acque di precipitazione. Dal punto di vista idrogeologico, sono stati individuati dei serbatoi abbastanza superficiali localizzati in formazioni permeabili e semipermeabili; circuiti più profondi possono essere ipotizzati solo nel caso di acque emergenti da formazioni vulcaniche antiche. Dal punto di vista geochimico, si distinguono 3 famiglie di acque: I) Acque bicarbonato-cloruro-calciche. 2) Acque cloruro-sodiche-bicarbonato-magnesiache. 3) Acque cloruro-sodiche-bicarbonato-calciche. Queste famiglie sono tra loro ricollegabili e rispecchiano, per il progressivo arricchimento di sali, i tipi di roccia in cui hanno circolato e l'ampiezza del loro circuito

Analisi multitemporale del consumo degli oliveti periurbani nel nordovest della Sardegna: il caso di studio della città di Sassari

In Sardinia the presence of olive stands plays an important role in economic business and landscape planning. In particularly, since the 16th century, the Miocene calcareous plateau of North- West is covered by an olive stand system mainly for olive oil production. These olive groves actually are composed by a local variety (Bosana) of which the oil is rich in antioxidant and flavour compounds and for this reason appreciated by the consumer. In the same region is located the city of Sassari, the second biggest city of Sardinia, which territory contains 50% of the whole olive stands of North Sardinia, most of them are concentrated in a “ring” around the city. The survey was conducted with historical and spatial explicit data of land-use and land-use change from the half of 19th century to the present (2007), to test the hypothesis that during the 20th century the area of olive stands decreased against urban expansion. In fact, changes in land-use (in particular those regarding agriculture lands) are a widespread phenomenon in Mediterranean regions and particularly intensive along urban borders. Historical land use data were derived from a variety of sources including cadastral data, maps and aerial photographs. A GIS was necessary to store, manipulate and analyse the digital information and to carry out land use change analysis. The historical analysis started by analysing the cadastral data of 1860, 1920 and 2007. The first one shows a higher density of olive groves in the ring around the city than the present. They were associated with vineyards, pasture and ploughed land. From 1860 to 1920 the olive stands increased due to destruction of the vineyards affected by Grape phylloxera. The information regarding the period between 1920 and 1977 and from 1977 to 2007 is given by aerial photographs that allow determine high resolution details in a spatial complex landscape. From 1960’s the city of Sassari had had the major expansion characterized also by an uncontrolled diffusive urbanization (sprawl) for the leak of a specific legislation. Between 1920 and 1977 the urban development caused the decline of the olive stands due cover density reduction or land use change, with the final result of disappearance of almost 100,000 olive trees in fifty years. The decline operates along the internal limit of the ring caused by urban expansion, and in several locations within the ring due the realization of small villages and the transformation of the olive grove in a garden. The former pattern is the principal factor of the olive landscape fragmentation. Despite the decline, in the external limit of the ring was verified the increase of olive groves but with lower magnitude than the decrease. Similar trends were evaluated for the period 1977-2007 using cadastral data, and digital land use maps. The main causes of olive stand decrease can be summarized in the request of lands for the realization of new industrial and 12 residential areas; in the people movement from the city to the rural area motivated by the better life condition; in the absence of a specific legislation for landscape protection and regulation. Finally the research gives some guideline for management and recovery of the olive groves in Sardinia which rule in Mediterranean ecosystems is recognized in a wide range of studies

Association between attention and heart rate fluctuations in pathological worriers

Recent data suggests that several psychopathological conditions are associated with alterations in the variability of behavioral and physiological responses. Pathological worry, defined as the cognitive representation of a potential threat, has been associated with reduced variability of heart beat oscillations (i.e., decreased heart rate variability; HRV) and lapses of attention indexed by reaction times (RTs). Clinical populations with attention deficit show RTs oscillation around 0.05 and 0.01 Hz when performing a sustained attention task. We tested the hypothesis that people who are prone to worry do it in a predictable oscillating pattern revealed through recurrent lapses in attention and concomitant oscillating HRV. Sixty healthy young adults (50% women) were recruited: 30 exceeded the clinical cut-off on the Penn State Worry Questionnaire (PSWQ; High-Worry, HW); the remaining 30 constituted the Low-Worry (LW) group. After a diagnostic assessment, participants performed two 15-min sustained attention tasks, interspersed by a standardized worry-induction procedure. RTs, HRV and moods were assessed. The analyses of the frequency spectrum showed that the HW group presents a significant higher and constant peak of RTs oscillation around 0.01 Hz (period 100 s) after the induction of worry, in comparison with their baseline and with the LW group that was not responsive to the induction procedure. Physiologically, the induction significantly reduced high-frequency HRV and such reduction was associated with levels of self-reported worry. Results are coherent with the oscillatory nature of the default mode network (DMN) and further confirm an association between cognitive rigidity and autonomic nervous system inflexibility

Studio geo-idrologico della Sardegna settentrionale: memoria 6.: il bacino idrografico del Fiume Temo

This comment consists essentially of three well defined partes: the is first physical geography, the second hydrogeology and the last is hydrogeochemistry. The AA., after a preliminary and organic geological investigation which permitted the preparation of the map (Fig. 3) in which the various geolithologic units are corelated, then made a particular study of the principal geomorphologic structures present in the entire basin. The multiple presence of such structure is justified in the geological difference of the formations present. Among the typical structures of the basic vulcanites was the evidence of cushion lava, block lava and tabularcolumn lava; among the typical acid vulcanites are the stratoid lava and the cave like structures. Also the evidence were the pointed tabular structures, the concave tabular structures and the dip-shop, tabular structures present in the series of lava flows, and of porous stone deposits and sea deposits in alternate stratus. The part relative to the hydrogeology was preceded by an examination of the climatology and the hydrometry of the basinc. Five meteorological rain measuring stations and two thermometeorological rain measuring stations were used for this study and the following information were gathered: - the maximum precipitations were concentrated in the late autumn period, in winter and in the early spring; the maximum aridity was during the summer months; there is a great irregularity in the intensity of the precipitations; within the area of the basin proportional differences of values of precipitation due to altitudes do not exist. The hydrometric characteristics of the basin have been brought to light using the information of hydrometric data given by the station at Reinamare. From an hydrological point of view, by suddividing the general area into thre larges complexes based on their permeability, the most important hydrogeological series and water structures of the basin have been located. As well as this, 60 perpetual water springs have been registered, and for the most part they have been actually identified and their waters have been analized and studied. These analysis have proved the waters as belonging to three families: magnesium-chloride water, sodium-bicarbonate water and sodium-sulphate water. This latter water family which includes the majority of the springs, whose sources are diffused almost all over the enti re area of the basin, presents a fairly similar chemical characteristic as we have found by using linear co-relations with pairs of geochemical «parameters»

(R) e (S)-2,2'-diidrossi-3,3'-dimetossi-5,5'-diallil-6,6'-dibromo-1,1'-bifenile un derivato chirale del <i>bis</i>-eugenolo

La presente comunicazione descrive la sintesi dell’equivalente bromurato chirale 2 del bis-eugenolo. La stabilità conformazionale del composto 2, e quindi la possibilità di isolare i due enantiomeri, potrebbe influenzare sostanzialmente la bioattivita’ della molecola

Synthesis and study of polyhydroxylated phenol derivatives with potential cosmetic and phytoiatric applications

Tyrosinase (polyphenol oxidase, E.C. 1.14.18.1) and laccase (phenol oxidase, E.C. 1.10.3.2) are multifunctional copper-containing enzymes, that are keys in melanin biosynthesis, melanisation in animals and browning in plants. Our study is aimed to prepare new monomer and dimer phenol derivatives as potential inhibitors of melanin production starting from natural hydroxylated aromatic units

Chemically modified β-cyclodextrins useful in developing biosensors of agricultural and food relevance

β-cyclodextrin (β-CD), a natural, non-toxic cycloeptaamilose macrocycle, is a useful biomatrix for immobilizing enzymes on a biosensor surface because of the affinity of its cavity for hydrophobic guest molecules (e.g., aminoacids). In this work β-CD has been successfully modified with different poly-carboxylic acids (PCAs) including 1,2,3,4-butanetetracarboxylic acid. Time activation, pH, pressure and stoichiometry were optimized in order to achieve selected substitutions on the macrocycle hydroxy groups. The modified β-CDs, prepared under mild conditions, are completely water-soluble and could be grafted on a biosensor surface

Bifenili idrossilati di origine naturale: building block per la preparazione di molecole di interesse biologico

Una delle ragioni del crescente interesse nei confronti dei bifenili idrossilati di origine naturale sono le importanti proprietà farmacologiche e biologiche manifestate da questi composti, in genere strutturalmente semplici. Le possibili variazioni geometriche determinate da trasformazioni chimiche della struttura bifenilica, rendono questa molecola un versatile prodotto di partenza per la preparazione di molecole bioattive

Dialettica dell'autorità

Ripensare e recuperare l'autorità come categoria generale e specifica di una particolare forma di rapporto comunicativo, significa tentare di riproporre tale categoria come centrale nel rapporto individuo-società. In altri termini: autorità come elemento significante della vita associativa. In questa direzione si muove il quadro teorico tracciato nella prima parte di questo lavoro, nella convinzione che i cambiamenti dentro e dietro il quotidiano siano talmente radicali da richiedere il ripensamento o la trasformazione o l'abbandono di alcune categorie. Con una indagine empirica, nella seconda e terza parte, si vuole mettere in luce il rapporto di autorità così come viene vissuto e percepito, mediante condizionamenti oggettivi e soggettivi di natura psichica e struttturale, da un campione di studentesse di Magistero. L'autorità "produce", infatti, una serie di atteggiamenti e comportamenti, empiricamente verificabili e misurabili

Sintesi e studi conformazionali di derivati 5,5'-disostituiti del 2,2'-dimetossi-1,1'-bifenile

In questo contesto, al fine di sintetizzare nuove strutture bifeniliche a chiralità assiale sono stati preparati i derivati 5,5’-disostituiti 1, 2, 3a-c a partire dal precursore comune 2,2’- diidrossi-1,1’-bifenile, un diolo commerciale a basso costo