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Gas industry reforms and consumers' prices in the European Union: An empirical analysis
Get PDFThe paper offers an exploratory empirical analysis of the impact on consumers’
welfare of the reforms of the gas industry in EU-15 area. After considering the key
features of the natural gas industry and of its reform in selected countries, we study
the relationship between regulatory reform indicators and price dynamics by means
of panel data techniques. We find that none of the relationships between price
dynamics and regulatory reform indicators is robust to different econometric
specifications. Our findings suggest that until now there is limited evidence of
beneficial effects of a standard package gas industry reforms for the European
consumers. Country specific factors and price inertia seem to be more important
than the reforms as determinants of consumers’ prices
Pollution adverse tourists and growth
Get PDFWe build a growth model in which tourism development generates pollution while tourists are pollution adverse. We establish that long run positive growth exists only for a particular value of tourists pollution adversion. Furthermore, we show that an intensive use of facilities is associated with a lower growth rate for destinations specialized in green tourism. We also see that if the destination can choose the degree of use of facilities, tourism will generate positive growth only if tourists are not too much pollution adverse. In this case the growth rate of the economy will be a negative function of tourists�adversion to pollution so that the "greener" the kind of tourism the destination address to, the slower its growth
La flora vascolare della penisola del Sinis (Sandregna occidentale)
Get PDFThe vascular flora of Sinis Peninsula (W Sardinia).The vascular flora of Sinis Peninsula
(W Sardinia) has been studied; 760 taxa, 615 of which were species, 134 subspecies, 10 varieties and
1 hybrid were found. They were included in 365 genera and 87 families. The Eudicots were dominant
over the other systematic groups. The most represented families were: Poaceae (99 taxonomic units),
Fabaceae and Asteraceae (85), Caryophyllaceae (33), Apiaceae (27) and Orchidaceae (24). The most
represented genera were: Trifolium (19), Silene (14), Limonium and Medicago (13), Ophrys (12),
Euphorbia and Vicia (10), Plantago (9), Allium (8) and, finally, Lotus, Ranunculus and Vulpia (7).
The contingent of endemics (54 taxonomic units) was 8,97% of the Mediterranean component showing
the dominance of Sardinian-Corsican (33,33%) and in the second place Sardinian elements (24,10%),
that together to reach 57,43% of the total. This flora consisted of 31 species, 17 subspecies and 6
varieties; 38 genera and 22 families were recognized. The most represented families were:
Plumbaginaceae (10), Asteraceae and Lamiaceae (5), Fabaceae (4), Alliaceae, Euphorbiaceae and
Ranunculaceae (3). The most represented genera were: Limonium (10) and Allium, Delphinium,
Euphorbia, Scrophularia, Silene, Teucrium (2). Based on the taxa present in the regional Italian Red
List, the species exclusive of Sardinia and important for the conservation has been included. For
these species we proposed the news categories of preservation following the IUCN criteria. Our
analysis, confirmed the presence of 12 taxa critically endangered as well as this group included the
majority of exclusive endemism of the territory. According to the geomorphological, geological and
bioclimatic data of the territories studied within the floristic analysis and in particular the endemic
and phytogeographical component, we proposed the creation of new biogeographic subsector named Sinisico
Indagine etnofarmacologica su Casimiroa edulis Llave et Lex
Get PDFIn order to evaluate the effects produced by the extracts of leaves, seeds and bark from Casimiroa edulis cultivated in Sardinia on the central nervous system, different behavioral tests were performed: spontaneous motor activity, anxyolitic, antidepressant, hypnotic-sedative, anticataleptic, anticonvulsant, antinociceptive and antinflammatory activities. The results revealed that the extract of seeds reduced spontaneous motor activity and rearing; in the forced swimming test (FST) it caused a potent sedative effect; in the test of carrageenan-induced paw edema it showed an antinflammatory activity; furthermore it reduced writhing acetic acid-induced (antinociceptive activity) and convulsion lithium-pilocarpine induced, while it significantly prolonged pentobarbital-induced hypnosis. The extract of leaves produced a like-anxyolitic action in the elevated plus maze test; in the FST it was as effective as fluoxetine in inducing shortening of immobility (like-antidepressant action); it reduced catalepsy haloperidol and PTZ-induced. The extract of bark significantly reduced immobility time in the FST and it increased pentobarbital-induced hypnosis
Studi di biologia della conservazione di specie vegetali endemiche della Sardegna nell'ambito del progetto "GENMEDOC"
Get PDFConservation biology studies on the endemic species from Sardinia within the "GENMEDOC" Project - The achieved results
of the Interreg IIIB "Genmedoc" project (2004-2006) are here reported. Data focused on the conservation biology studies
of Sardinian endemic species are showed in this work. During the project 26 populations of 16 species were investigated
and the ex situ conservation for these species was guaranteed by storage of 65 seed lots in the seedbank. Furthermore 8
species were analysed by in situ characterization of 17 populations: for each population ecological studies were carried out.
Real and possible threats that affect these populations were detected. For 6 species effective germination protocols were
identified and also valied by other two project partners. These protocols allow evaluating seed quality for the stored lots
and their longevity during next years; moreover the knowledge of the best germination conditions will be able to schedule
a possible cultivation or an in situ re-introduction for these species. These results were obtained by sistematic conservation
biology studies of threatened endemic species of Sardinia by a tested and internationally acknowledged methodology
Meccanismo catalitico della perossidasi da Euphorbia characias
Get PDFPeroxidases (EC 1.11.1.1-16) are a group of oxidoreductases utilizing hydrogen peroxide, or other peroxides, to oxidize a second reducing substrate belonging to a large array of organic and inorganic compounds. A class III peroxidase isolated from the latex of Mediterranean shrub Euphorbia characias (ELP), has peculiar features with respect to the other eme-peroxidases. In fact ELP is the first example of peroxidase that responds as an on/off switch to variation in the external Ca2+ level and represents the first peroxidase regulated by the Ca2+/calmodulin system.
The catalytic mechanism of ELP was well studied and characterized. In the present thesis we investigate the catalyc pathways of ELP with hydrogen peroxide as the unique substrate and in both the presence and absence of calcium ions showing the presence oh three different pathways. Pathway I: ELP shows catalise-like activity catalyzing decomposition of hydrogen peroxide to water and oxygen; Pathway II involves the return to native enzyme with the concomitant formation of superoxyde anion; Pathway III involves an irresistible loss of enzyme activity, with hydrogen peroxide acting as a suicide substrate.
Because the importance of the Ca2+ ions to influence the catalytic activity of Euphorbia peroxidase, we investigate the effects of another divalent cation (Ni2+) on the catalytic pathways of native ELP and in the presence of calcium ions. The enzyme is strongly inhibited by nickel ions an the absence of Ca2+, whereas, in the presence of both Ca2+ and Ni2+, the enzymatic activity is enhanced. The reported results are compatible with the hypothesis that ELP has Ni2+-binding sites eith opposite functional effects
Conservación ex situ de plantas silvestres
Get PDFLa conservación “ex situ” de plantas silvestres es reconocida como un complemento importantísimo de las acciones sobre el terreno, ya que su uso contribuye a proteger y custodiar las especies para evitar su desaparición. En este campo, en los últimos tiempos, se está impulsando el desarrollo de bancos de germoplasma dedicados a la conservación de semillas de plantas silvestres (imprescindibles para la conservación ex situ).
Creemos que esta publicación, sin duda necesaria, llena un importante hueco en la literatura en español relacionada con los bancos de germoplasma y será de gran interés para quienes trabajan dentro del panorama de la conservación de plantas, “ex situ”, en España, pero también para un amplio espectro de técnicos que lo hacen en el mundo hispano-americano. La publicación, corolario del apoyo del Gobierno del Principado de Asturias al banco de germoplasma del Jardín Botánico Atlántico de Gijón ha sido promovida por el equipo científico del mismo, dependiente de la Universidad de Oviedo, y posible gracias a la colaboración con los centros italianos ISPRA (Istituto Superiore per la Protezione e la Ricerca Ambientale) y CCB (Centro Conservazione Biodiversitá e Banca del Germoplasma della Sardegna -Universitá degli Studi di Cagliari). Para el desarrollo de la misma ha sido imprescindible además el
trabajo entusiasta de 33 investigadores de cuatro países (Italia, España, Francia y Portugal), lo que convierte a la obra en todo un reto arriesgado, de larga gestación y de nada fácil coordinación. Llevada a buen puerto, finalmente se ha convertido en un ejemplo singular, de cómo coordinando esfuerzos y con buena voluntad, se puede avanzar y trabajar más rápido en aras de la conservación.
La edición de esta publicación se enmarca en el Convenio de Colaboración entre el Gobierno del Principado de Asturias y la Obra Social ”la Caixa” firmado el doce de mayo de dos mil
seis, dentro de la serie sobre vida silvestre; es un paso más en el compromiso de Asturias con la biodiversidad, y una pequeña, pero interesante, aportación a los objetivos que estableció la Conferencia de las Partes de la Convención sobre Diversidad Biológica, celebrada en La Haya
en 2002, y que sentó las bases para la Estrategia Global de la Conservación Vegetal (a la que está adherida España). Pretende ser también un granito de arena para la consecución harto difícil de ese objetivo que hoy une a todos los conservacionistas del mundo: detener la pérdida
de biodiversidad antes de 2010
Identificazione e caratterizzazione di un gene associato all'asma ad insorgenza precoce persistente
Get PDFAsthma is a multifactorial disease influenced by genetic and environmental factors. The aim of the study is to identify new susceptibility genes, using the Sardinian founder population, in which limited heterogeneity as well as of environmental conditions should facilitate the study of multifactorial traits. Asthma was diagnosed by a pulmonary physician, in accordante with American Thoracic Society criteria. We performed linkage and association analyses by transmission/disequilibrium test and case-control analysis in the candidate region 12q13-24 already implicated in asthma etiology in multiple populations We selected a cutoff age of 13 years at asthma onset, to stratify the sample and detected significant linkage to a portion of 12q13-24. We identified IRAK-M as the gene in the candidate region implicated in early-onset persistent asthma. We defined protective and predisposing haplotypes and replicated associations in an outbred Italian population. Sequence analysis in 100 patients found mutations in the IRAK-M coding region. Immunohistochemistry of lung biopsies showed that IRAK-M is highly expressed in epithelial cells. Here, was report that variants in the interleukin-1 receptor associated kinase-M gene are associated with early-onset persistent asthma and indicate IRAK-M as a potential new target for therapeutic intervention against asthma and atopic diseases
Studio di fenomeni di subsidenza localizzata (sinkhole) con applicazione di tecniche geofisiche integrate per la programmazione in intrventi di protezione civile e di ridefinizione dell'uso del territorio
No full textThe word “sinkhole” is increasingly used to indicate localized subsidence phenomena. In spite of the increasing awareness of the risk associated with this kind of event, sinkholes receive little attention from local authorities and technicians, especially in Italy. The real threat that these natural phenomena pose to public safety and to regional development, should encourage local governments to take action through specific planned action. In fact, sinkholes cannot be thought of as occurring unexpectedly; their spatial distribution, recurrence and type of development clearly show that they occur in specific geological and environmental conditions and are triggered by several concomitant factors. Therefore the widespread belief that sinkholes are unpredictable events simply derives from a poor understanding of the phenomenon.
The purpose of this work is to provide a structured and complete overview through a detailed analysis of Italian and foreign case histories, summarizing the environmental conditions in which sinkholes occur, as well as the many factors and mechanisms underlying their formation. The need for a multidisciplinary approach is emphasized, based on the comparison and integration of results achieved using different investigation methods to obtain geological, hydrogeological and geochemical information, also examining several real cases. The importance and suitability of surveys based on geophysical techniques is stressed. To illustrate this, an overview of the results achieved using a variety of geophysical methods in numerous case studies of sinkholes and sinkhole-prone areas is provided.
Lastly, the experimental part of this work, developed in the frame of this PhD course, is presented. It consists of a geophysical study of the Cixerri Valley, in SW Sardinia, Italy, where several sinkholes have appeared since 1996. Among the different geophysical survey techniques used in this study, the gravity method proved especially effective for detecting the geological and structural conditions that appear to be responsible for sinkhole formation. A sinkhole hazard map of the area has been drawn up on the basis of the gravity anomalies identified.
The aim of this work is not the theoretical and practical development of geophysical techniques, which goes beyond the original scope of the study. It intends instead to define a possible route to be pursued in the analysis of sinkhole prone areas, that is able to provide valuable scientific information useful for gaining a better understanding of sinkhole formation mechanisms and how they are related to the general geological setting. With this information it would be possible to identify sinkhole hazard areas and local conditions, essential information for planning prevention and monitoring, securing these areas and for their reclamation
Estrazioni di sostanze naturali da piante della flora sarda: struttura e applicazioni. Chemorecezione gustativa: sintesi e relazioni attività-struttura di molecole attive sul sapore
Get PDFThe presence of a lactonic system and/or a furanic element is the most important structural element in the bitter isoprenoid group (a class of compounds structurally heterogeneous). These substances are able to put in action more than one bitter receptors and to be used in programs of derivatives for chiral syntons and libraries of bioactive compounds.
The research has been focused on compounds that have these structural characteristics using the availability of receptioral models for their sensory characterization. Within the set of these compounds there is the class of sesquiterpenic lactones, above all the grosseimin (from the guaianolid family) extracted from the artichoke and the arborescin extracted from the arthemisia. These lactones are able to put on work more than one bitter receptors as the arborescin, able to put on work five bitter receptors.
The research has managed for the bitter isoprenoids extracted from the two plans as follow: isolation of sesquiterpenic lactones; systematic structural modification of lactones extracted by means of organic synthesis methodology (a library of derivatives for the study of structure-activity relation was found); research of potential inhibitories of bitter property in natural and analogous compounds