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Chemo and biodetection in liquid with organic transistor
Get PDFIn the past, quality and quantity of the substances could be evaluated only in analytical chemistry laboratories, well-equipped with centralized and powerful data centres.
The rising of miniaturized technology has made possible to conceive the realization of portable devices, i.e. chemical sensors capable to analyse small quantities in situ.
Nowadays, the availability of portable devices allows to test those samples which are di�cult or impossible to transport for long distances without degradation.
This work concerns the realization of two kinds of devices for detection of chemical and biological species in liquids by using organic transistor technology. One device,
which is named Organic Charge Modulated Field E�ect Transistor (OCMFET), is a charge sensor which was tested as pH and DNA sensor. The other device is an Organic Electrochemical Transistor (OECT) entirely made of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) which was realized by ink-jet printing. As these devices can be fabricated with low-cost processes, they can be considered portable and disposable. A brief introduction on sensors, organic technology and the aim of this work is de-
scribed in chapter one. In order to explain the reasons and the speci�c choices behind the development of these sensors, an overview of the most relevant sensing applications realized with Organic Thin Film Transistors and Organic Electrochemical Transistors is reported in chapter two. The working principle, the materials and methods and the recorded experimental results related to the OCMFET are treated in chapter three. A
brief introduction on OECTs with a PEDOT:PSS channel and the study carried out to elucidate the operating regime of the OECT all made of PEDOT:PSS is treated in
chapter four. The conclusions about this work are brie
y summarized in chapter �ve. An overview on organic semiconductors and Organic Thin Film Transistors (OTFTs),
the electrochemical techniques used in this work are treated in the appendixes
Il leasing d’azienda
Get PDFIs it possible to admit a business under a leasing contract?
If no problems arise in the leasing contract because it is an unregulated contract, questions are raised by the
business. In fact, leasing is a flexible contract that may concern any type of good and that can be adapted to any
kind of concern between the contract parties.
On the contrary, business is a complex and mutable reality. It’s composed not only of tangible assets, but even of intangible assets, as well as of a whole string of juridical situations. Moreover, business is in continous
development: business value estimation and goodwill can increase or go down, goods can become obsolete, even
within a brief period of usage. Furthermore, business transfer produces results not only between the lessee and
the lessor but also between others involved in the legal transaction. Finally, the Italian civil code disciplines
only company (business) sales, usufruct and renting, meaning that it’s very difficult to ascertain if our law
allows different modalities of business transfer apart from those specified. So how can contract leasing and business discipline be combine? Firstly, it’s necessary to solve the business leasing configuration problem. It’s important to establish (1) if it is possible, both in theory and in practice, to make such an agreement, especially concerning intangible assets and all juridical situations connected with business, and (2) if it is possible to conceive of a leasing in which a business, considered as one entity, is admitted or if it is necessary to sign a leasing contract for every single business component. This is not such a simple problem to solve. In fact, the main practical obstacle is the so-called investment risk. Who takes it? If the business isn’t bought by the lessee at the end of the contract, it returns to the lessor and even if it isn’t used and exploited, it produces results and needs to be managed. So who’s responsibility is it to manage it? The lessor, another new lessee, another new contract party, perhaps a guarantor? Furthermore what about its status after the return to the lessor and before a next potential transfer? What about contracts, credits, debts, intangible assets, management risk, warranties and of a ban on competition? Moreover, to whom will business management
advantages and disadvantages be related? How can they be connected to the lessor or to the lessee or to a third
contractual leasing party, perhaps a guarantor? Also, if there is a succession of lessees and business managements, how should they be considered? Should they be considered separately or as one complex management? What about customers, suppliers, workers and others related to the business in general? How is it possible to safeguard their interests? Perhaps is it possible to create a uniform manage trend? Only after having solved these problems, is it possible to analyze, in every single detail, leasing contractual structure (both objective and subjective), due diligence, business value estimation, contract performance and business credit, debt and contract succession, hypothesis and remedies of breach of contract and discharge,
bankrupted results, business return regime (structure and results), accounting and fiscal aspects. An analytic analysis is reserved for the role of the guarantor and for the business management trend as the main and essential features of business leasing contract. The whole treatise is completed with a general part concerning the leasing contract and the business (especially intangible assets and business transfer rules) with specific references to legal doctrine and jurisprudence, both Italian and foreign (French, Spanish and English) and to practical commercial cases
Nuovi approcci molecolari per lo studio di malattie monogeniche rare: utilizzo dell’exome sequencing per la ricerca di geni malattia
Get PDFAs defined by European Union, rare diseases are a broad range of disorders with prevalence ≤ 5/10000 in general population. Some rare diseases are the result of bacterial or viral infections, allergies and environmental causes, or are degenerative and proliferative, but the most have a genetic etiology. Discovering alleles underlying genetic conditions is essential for the comprehension of the pathogenesis and for the prevention of the disease through identification of carriers and prenatal diagnosis. Conventional strategies for disease gene discovery, like positional cloning and Sanger sequencing of candidate genes, have led, to date, to detect the genetic detrminants of about 3000 Mendelian phenotypes, representing about the 50% of genetic phenotypes known. In recent years many genes causing human genetic disorders have been identified through the analysis of the variants revealed by whole-genome or exome sequencing by “Next-Generation” sequencing technologies (NGS).
Herein, we report the results of an exome sequencing project applied to the identification of the gene responsible for a rare and genetically heterogenous ciliopathy, the Jeune Syndrome (Asphyxiating thoracic dystrophy, JATD, MIM 208500). Exome sequencing has been performed on the affected and respective parents of two unrelated Sardinian families in which genetic basis of the disease was not yet elucidated. Exome variants analysis strategies led us to identify a missense substitution in DYNC2H1 (MIM 603297), a gene involved in intraflagellar transport pathways of cilia that has been previously associated to the disease (Dagoneau et al., 2009; Merrill et al., 2009). The substiution has been found in homozygosity in the probands of one of the two families JATD and in heterozygosity in their parents. To date, exome analysis is still in progress in the second family JATD. For this family, there was only one gene that has been considered a good candidate for the disease, MAP1S (MIM 607573), that codifies for a microtubule associated protein. Unfortunately, the compound heterozygous state for two variants, revealed by exome sequencing in the proband, was not validated by variants resequencing with Sanger method. No deleterious variants have been found in DYNC2H1 but the involvement of this gene in disease pathogenesis cannot be excluded because of the failed capture of some exons, that will be resequenced by NGS technologies. Studies in vivo and in vitro could explain the functional impact of the DYNC2H1 missense substitution identified by exome sequencing on the protein function
Specific BIVA standards 2013
No full textThe database comprises anthropometric and bioelectrical data of a cross-sectional sample of 560 healthy individuals (265 men and 295 women) 65 to 100 y of age (men: 77.0 ± 7.2 y; women: 76.0 ± 7.1 y)
Il Sistema di Revenue Management strumento per lo sviluppo turistico sostenibile delle destinazioni
Get PDFBusinesses interact constantly with the environment, realizing several and heterogeneous exchanges. Organizations can be considered a system of different interests, frequently conflicting and the satisfaction of different stakeholders is a condition of success and survival. National and international literature attempts to explain the complex connection between companies and environment. In particular, the Stakeholder Theory considers crucial for businesses the identification of different stakeholders and their involvement in decision-making process. In this context, profit can not be considered the only purpose of companies existence and business aims become more numerous and different.
The Stakeholder Theory is often utilized as framework for tourism studies, in particular in Sustainable Tourism Development research. In fact, authors consider sustainable the tourism development able to satisfy interests of different stakeholders, traditionally identified as local community and government, businesses, tourists and natural environment. Tourism businesses have to guarantee the optimal use of natural resources, the respect of socio-cultural tradition of local community and the creation of socio-economic benefits for all stakeholders in destinations. An obstacle to sustainable tourism development that characterizes a number of destinations worldwide is tourism demand seasonality. In fact, its negative impact on the environment, economy and communities may be highly significant. Pollution, difficulties in the use of public services, stress for residents, seasonal incomes, are all examples of the negative effects of seasonality. According to the World Tourism Organization (2004) the limitation of seasonality can favour the sustainability of tourism.
Literature suggests private and public strategies to minimize the negative effects of tourism seasonality, as diversification of tourism products, identification of new market segments, launching events, application of public instruments like eco-taxes and use of differential pricing policies. Revenue Management is a managerial system based on differential pricing and able to affect price sensitive tourists. This research attempts to verify if Revenue Management, created to maximize profits in tourism companies, can also mitigate the seasonality of tourism demand, producing benefits for different stakeholders of destinations and contributing to Sustainable Tourism Development. In particular, the study attempts to answer the following research questions: 1) Can Revenue Management control the flow of tourist demand? 2) Can Revenue Management limit seasonality, producing benefits for different stakeholders of a destination? 3) Can Revenue Management favor the development of Sustainable Tourism?
The literature review on Stakeholder Theory, Sustainable Tourism Development, tourism seasonality and Revenue Management forms the foundation of the research, based on a case study approach looking at a significant destination located in the Southern coast of Sardinia, Italy. A deductive methodology was applied and qualitative and quantitative methods were utilized. This study shows that Revenue Management has the potential to limit tourism seasonality, to mitigate negative impacts occurring from tourism activities, producing benefits for local community and to contribute to Sustainable Tourism Development
Determinazione delle proprietà del petrolio tramite spettroscopia ¹H-NMR e analisi chemiometrica
Get PDFCurrently, the refiners have to cope with an increasing demand of high quality distillates of tighter specifications, while facing the need to process increasingly heavier and poorer quality crudes. Furthermore, the recent trends to process heavy
and lower cost crudes spurred the interest on residue upgrading, normally referred to as bottom of the barrel processing, as a means to fully exploit the crudes’ heavy
fractions. To reach these goals, refiners are looking at optimizing production and improving selection of crudes and crude mixtures to be processed which can only be
achieved through a detailed knowledge of the composition and quality of feed and finished products. Generally, to know the yield and the quality of the crude oils, it is necessary to perform an atmospheric distillation and to characterize their fractions at laboratory level (crude assay). In order to characterize the crude residue, a vacuum distillation is needed and the physical-chemical properties of the resulting fractions must be measured. The time required for these characterization measurements is between 2 and 3 weeks, the amount of sample needed is large, up to 10 Kg, and the overall routine is generally expensive in terms of instruments, man-hours and consumables. Furthermore, crudes quality is not constant and tends to fluctuate over time and with field. To ensure technically, economically, and environmentally proper refining operations there is a substantial need for fast analytical methods for characterization of crude oils and their residua. During this PhD research, as a fast and viable alternative, 1H NMR spectroscopy, combined with chemometrics, has been used. To exploit the full
information content of the NMR data acquired on complex systems, as crude oils, chemometric regression techniques as partial least squares (PLS) have been developed. The proton NMR spectra of neat crude samples have been recorded using a 300-MHz laboratory spectrometer. PLS regression models for prediction were built using analytical data obtained at the SARTEC laboratory. The attention was focused
on the study of the most common crude assay properties such as API gravity, TBP distillation yields, KUOP factor, pour point, total acidity number and sulfur, carbon,
hydrogen and nitrogen content. Successively, it was proved that also other important physical-chemical parameters can be predicted using the NMR. Among these asphaltenes, carbon residue, metal content, and especially the breakdown of aromatic classes content which, despite their impact on process, have been overlooked in previous researches.
In addition, this thesis, demonstrates the possibility to predict most of the properties of atmospheric and vacuum distillation residua directly from the 1H NMR spectra of crudes. The speed of this method and most of all the possibility to avoid the distillation of the sample prior to analysis, opens to the opportunity to use real
time property data of residua to evaluate process strategies and to assess the impact on downstream processes. Chemometric modelling was carried out for the most important property of residua, i.e. yields, density, viscosity, sulfur content, asphaltenes, carbon residue, nitrogen, hydrogen and carbon content
Population genetic analyses of Ferula gr. communis and Ruta gr. corsica in the Tyrrhenian area
Get PDFThe Western Mediterranean Islands represent a major hotspot of plant diversity in the Mediterranean area and are priority regions for conservation due to their high number of endemic plant species. However, information supporting human decision-making on the conservation of these species is still scarce, especially at the genetic level.
In this thesis the first assessment is reported of the genetic diversity and structure of the Corso-Sardinian endemic Ferula arrigonii (Apiaceae) and of Ruta corsica and R. lamarmorae (Rutaceae), endemic to Corsica and Sardinia, respectively. The main aim was to provide suggestions for the conservation of these rare species. In the case of the genus Ferula, the widespread F. communis was also analyzed in order to gain information on its genetic diversity
and structure in the Tyrrhenian area and to compare it with the endemic F. arrigonii. Nine populations (179 individuals) of F. arrigonii were investigated by means of AFLP (Amplified Fragment Length Polymorphism) markers. Results indicate that this species is characterized by high levels of genetic polymorphism (about 92% of the fragments were polymorphic), a low inter-population differentiation (Gst = 0.124) and a high intra-population variation (Hw = 0.317). PCoA, Bayesian analysis and neighbor-joining clustering were also employed to investigate the genetic structure of this species. Three genetically distinct groups
were detected, although with considerable overlap between sampling sites. The AFLP analysis of 12 populations of F. communis (168 individuals) from four different islands (i.e. Minorca, Corsica, Sardinia and Sicily) and the Tyrrhenian coast revealed that the populations form an homogeneous group irrespective of the geographic provenance, with the only exception of individuals belonging to F. communis subsp. glauca. Genetic diversity values were not significantly different with respect to those of the endemic F. arrigonii. As regards the genus Ruta, a set of 11 microsatellite markers was used to assess the genetic diversity and the spatial structure of the genetic variation of 96 individuals of R. corsica (6
populations) and 63 individuals of R. lamarmorae (3 populations). The markers were highly polymorphic and detected 10 alleles per locus on average. Overall, results showed that both species have maintained relatively high levels of genetic diversity (He = 0.579 and 0.639, Ho =
0.558 and 0.591 for R. corsica and R. lamarmorae, respectively). Pairwise Fst values (0.035 – 0.351) indicated a low-moderate differentiation for most pairs of populations. AMOVA revealed that 80% of the genetic variation resides within populations, while only 4% is due to differences among the two species. The analyses of the spatial genetic structure suggested the clustering of
the individuals into two groups, approximately corresponding to taxonomic affiliations
Biology and conservation status of Juniperus macrocarpa Sm. in Sardinia
Get PDFThe present Ph.D. thesis aimed to provide a better understanding of Juniperus macrocarpa and the habitat that it characterizes (Juniperus spp. habitat; European priority habitat) in Sardinian coastal dunes, as well as to achieve results useful to support in situ and ex situ conservation actions. In particular, the specific aims of the thesis were: (1) to analyse morphological variation in seeds of Mediterranean Juniperus taxa (at inter- and intraspecific level) and morphometric differences in J. macrocarpa seeds collected in different populations, seasons and sources; (2) to evaluate the effect of the collecting season, source, laboratory pre-treatments and temperatures on seed viability and germination of J. macrocarpa; (3) to investigate factors affecting seedling emergence, survival and growth of the species; (4) to explore the floristic variability of the habitat in Sardinia in relation to geographic, climatic and human variables, as well as the potential effect of human disturbance and sampling period on key plant parameters; and finally (5) to assess the conservation status of this habitat in Sardinia.
In the first chapter, a statistical classifier for Mediterranean Juniperus taxa based on seed morphometric parameters analysed by image analysis techniques, was tested at interspecific, specific and intraspecific levels. Analysed seeds came from galbules of Juniperus taxa collected from different regions of the Mediterranean Basin and galbules of J. macrocarpa collected in 2010 from four Sardinian populations, in two seasons and in plants and soil. Two taxonomic treatments for Juniperus genus (Flora Europaea and The Plant List) were compared and inter-population, seasonal and source variability in seed morphology were analysed. High percentages of correct
identification were reached for both taxonomic treatments at specific and intraspecific level and from the comparison among taxa of the J. oxycedrus, J. communis and J. phoenicea complexes. Moreover, this statistical classifier discriminated J. macrocarpa seeds collected in spring better than those collected in autumn, but it seemed not to be able to discriminate those seeds collected from plants and soil, nor those ones collected in different populations from the same geographical region.
In the subsequent chapter, seed viability and germination phenology of J. macrocarpa were investigated. For this purpose, ripe galbules in four localities and in two seasons, both from plants and soil, were collected. In order to verify the presence of physiological dormancy, warm (W) and cold stratification (C), two combinations of them (W+C and C+W), and no pre-treatment (control) were applied. After pre-treatments, seeds were incubated in a range of constant (10–25°C) and alternating (25⁄10°C) temperatures. Seed viability was low (ca. 40%) and the source (plant or soil) had not a significant effect on it, but it varied significantly according to season, showing lower percentages for seeds collected in autumn than in spring. Seed germination was low (ca. 10%), the control and W were the most effective on stimulating germination, while C negatively affected germination. The best temperatures for germination were 15 and 20°C and seeds collected in spring showed higher germination percentages (ca. 11%) than in autumn (ca. 7%). Seeds of J. macrocarpa are dormant and the results of this study suggested the presence of secondary dormancy induced by cold stratification. The germination phenology all along the dispersal season (from autumn to spring) was illustrated, as well as the potentiality of this taxon to create a soil seed bank.
In the third chapter, factors affecting emergence, survival and growth of J. macrocarpa seedlings, were investigated. For this study, permanent plots were placed and periodically monitored. Within them, besides seedling parameters (emergence, survival and growth), several biotic and abiotic variables (solar radiation, tree cover, herbaceous plus scrub cover, distance from the closer J. macrocarpa female, number of galbules on the soil and event number of herbivore trace) were measured. Linear mixed-effects models were used to test the relative importance of different groups of explanatory variables on seedling parameters. A total of 536 seedlings were marked, most of which emerged in winter. The "microclimate" was the best fit model explaining emergence, highlighting the positive relation between the number of emerged seedlings and tree cover. Survival was very low and most of the seedlings died in the first months from emergence, reaching the highest mortality rate in the first summer. High values of both herbivory and solar irradiation increased mortality risk. Our results confirmed that J. macrocarpa is a slow growing species, and no seedlings reached the subsequent size class. Moreover, growth depended on suitable microhabitats, and in particular it was positively related to tree cover, hours of sunlight, and
herbaceous plus scrub cover. Despite these relevant results, long-term studies are needed to identify key issues in the life cycle of J. macrocarpa (e.g. germination, fitness, and recruitment).
In the last chapter, the floristic variability of Juniperus spp. habitat in Sardinia in relation to geographic, climatic and human variables was explored. Two data sets were created: the first one by inputting phytosociological relevés available in literature and our own relevés; the second one by including for each relevé geographic, climatic and floristic variables, as well as sampling period and human disturbance as categorical variables. The floristic composition differed among sites and this variation was mainly ruled by a latitudinal gradient linked to a climatic gradient. Regarding the results of key parameters in the evaluation of the habitat quality, floristic richness was positively influenced by low and medium level of human disturbance; the endemic taxa cover was positively related to a medium level of human disturbance, while the alien taxa cover was positively related to recent samplings. The conservation status of Juniperus spp. habitat in Sardinia following the IUCN protocol we also assessed. Preliminary results showed that this habitat should be considered as endangered (EN) at a regional level.
In conclusion, our results gave new findings for the recovery and conservation planning of the species and the habitat under study. Specifically, we found that spring was the best season for seed collection. We also suggest: autumn as the period for planting or sowing, with planting being preferable to sowing; shielding plants from solar radiation under canopy; the application of techniques such as organic blanket when sowing is the selected option. In addition, in order to improve the conservation status of Juniperus spp. habitat, we advise management measures such as the eradication of alien taxa, as well as interventions aimed to reduce human impact on the dune systems
Monte Carlo simulation studies for spatially fractionated radiation therapy techniques
Get PDFThe purpose of this work was to evaluate the possible gain in tissue sparing in hadrontherapy when a spatial fractionation of the dose is used. Monte Carlo simulations (GATE v.6) have been used as a method to assess the dose distributions in a cylindrical water phantom (16 cm height and 16 cm of diameter). The phantom was irradiated with carbon and oxygen minibeams of 0.7 mm of beam width, and with protons in a grid geometry configuration. Several centre-to-centre distances, covering a 2 x 2 cm2 area, have been taken into account. The ratio of the peak-to-valley doses (PVDR) and the penumbrae was used as evaluation parameter, since PVDR is considered to be a very relevant dosimetric parameter for tissue sparing. Extremely high PVDRs values and very narrow penumbrae were obtained in all depths. This means that this new way of dose delivery might allow the use of higher and potentially curative doses in
clinical cases where tissue tolerances are a limit to achieve a curative treatment. The high PVDR obtained and the small penumbrae in comparison with existing radiosurgery
techniques, suggest a potential gain in healthy tissue sparing in those new techniques
Taphonomy and Palaeoecology of multi-element skeleton invertebrates: a genetic model for exceptional preservation
Get PDFThe aim of the research is to improve the understanding on the origin of fossil accumulations by investigating their taphonomic and sedimentological features and by
using stratigraphic data and the autecology of the organisms forming the shell beds. A number of highly different oligospecific high dense fossil accumulations of wellpreserved, multi-element skeleton invertebrates, such as arthropods and echinoids, were studied. The first case studied concerns the Ordovician trilobite-like arthropod Tariccoia arrusensis, which is found locally within the grey siltstones of Riu Is Arrus Member (Monte Argentu Formation, Upper Ordovician), cropping out along the valley of the creek Riu Is Arrus, SE Fluminimaggiore (SW Sardinia). The locality Roia Srappas is the most distinctive whit regards to the fossil content. The facies analysis allows documenting a clastic sequence whose origin is related to turbidity currents(hyperpycnal flows) generated by a flood-dominated fluvio-deltaic system entering in lagoonal or protected shallow marine settings. Two taphofacies are recorded: tf1 consists of a high density of articulated remains, which constantly show convex down orientation, while tf2 consists exclusively of disarticulated remains randomly oriented. The preservation state and preferred orientation of arthropods in the tf1 leads to infer gentle transport by mud plumes, related to hyperpycnal flows, rapid burial and low scavenging and bioturbation. The second case focused on four clypeasteroid mass occurrences from the Lower Miocene of Sardinia, which are analyzed and compared. Two clypeasteroid assemblages
were found within the Nurallao Formation (Late Oligocene-Burdigalian). The other two investigated clypeasteroid assemblages that were investigated, are found within the
Calcari di Mores Formation (Late Burdigalian). These fossil echinoid deposits show a 2 low taxonomic diversity: two assemblages are dominated by the genus Amphiope while
the other is dominated by Parascutella with subordinate Clypeaster. Although the four sand dollar deposits, which are the object of this study, can be assigned to a shoreface
environment, there are differences in their features and origin. Three different genetic mechanisms, such as multiple in situ reworking, storm deposition and autochthonous accumulation can be inferred. The third case focused on regular echinoid and spatangoid mass accumulations, which are extremely rare in the fossil record of the Miocene of Sardinia. In the Lower
Burdigalian sediments of the Marmilla Formation two monospecific regular echinoid and spatangoid mass occurrences were found. The regular echinoid assemblage consists of a dense accumulation of phymosomatid echinoid Anisophyma n.g.n.sp., which is decribed and illustrated. The other echinoid assemblage is a monospecific Brissopsis
beds. The third regular echinoid mass accumulation, which is found within the Gesturi Marls (Upper Burdigalian to Langhian), is a sea urchin spine bed with rare and poorlypreserved complete tests. Although the three studied echinoid mass accumulations can be trace to a storm-dominated offshore environment, observed variations in the
taphonomic and sedimentologic features are due to three different genetic mechanisms such as, rapid buried living community (obrution), time-averaged fossil bed by sediment
starvation, and distal tempestite event. The studied mass accumulations allowed explaining the nature and the distribution of the fossil concentrations across a wide
spectrum of environments. Nearshore depositional environments are dominated by sedimentological concentrations but can also include sedimentologically overprinted biological concentrations. In deeper water environments shell-bed development can mainly be the results of ecologic (biologic) mechanisms, shell accumulation during episodes of sediment starvation and rapid burial by storm events. The analysis of multi3
element skeleton mass accumulations showed that these fossil deposits are a useful tool for palaeoenvironment and palaeoecological reconstructions