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Area di ripopolamento di Palinurus Elephas: valutazioni sulla gestione della risorsa
No full textThe work aims to assess the effectiveness of the no take zones from a management
point of view by comparing the population structure of the spiny lobster Palinurus
elephas (Fabricius, 1787) along the Sardinian waters.
Since 1998, the Region of Sardinia in cooperation with the University of Cagliari, is
pursuing a restocking program (Regional Law n. 776/1998) that provides the
establishment of some protected areas.
During the 2011-2015 period, an extensive monitoring was carried out inside and
outside of four specific protected areas: Su Pallosu (central-western Sardinia), Bosa
(western Sardinia), Buggerru (south-west Sardinia) and Castelsardo (north Sardinia).
A good number of biometric data (length, weight and sex) has been collected during
this phase and then analyzed by the virtual population analysis (VPA).
The results obtained have allowed us to detect significant differences between
populations belonging to different zones. In particular, there was a trend to full
recovery of the populations exploited inside the protected areas after only few years.
Furthermore, especially for the area of Su Pallosu, they are recognized important
spillover phenomena, known to improve the fisheries in the long term.
However, in other areas was not observed these particular phenomena, probably due
to the lower period of implementation of the management plan. The adult migration
to the neighboring areas represents one of the main objectives of the project, as it is
an important indicator of effectiveness of the no take areas.
This kind of study represent a fundamental step for the development of integrated
management plans and protection measures, taking into account both the production
requirements, and the ecological factors related to these important resources
Bioengineering-enhanced neurosurgical solutions
Get PDFThe advancements in basic sciences and the availability of sophisticated technological aids have led over the last few years to the rise of innovative surgical strategies, the identification of better prognostic/predictive biomolecular factors, and the development of novel drugs all meant to profoundly impact the outcome of neurosurgical patients. This thesis touches upon the window of opportunity to exploit bioengineering techniques in three subspecialties of this vast discipline: neuro-oncology, radiosurgery and neuro-traumatology. After a thorough identification of some unresolved clinical problems and the limits of current management strategies in those areas, some technical solutions are proposed and defined from either experimental hypothesis or clinical research investigations.
The neuro-oncology section presents the exciting topic of nanodrugs for adjuvant chemotherapy in high-grade gliomas, the most aggressive primary brain tumours. The use of hyaluronic acid nanoshells is proposed to encapsulate prodrugs and exploit the mechanisms of interaction between glioma cells and hyaluronic acid, a natural component of extracellular matrix. The theoretical advantages of this approach are discussed with details regarding the possible scalability of this technique to increase the efficacy and biodegradability of other molecules suitable as contrast media for neuro-imaging and radiotracers for nuclear medicine investigations.
The radiosurgery section in fact continues the previous one, highlighting the rationale for further implementation of radiosurgical protocols thanks to nanoshell-encapsulated radioenhancers and multi-imaging fusion protocols. Experimental data on the optimization of radiosurgical plans for artero-venous malformations close to the motor strip or basal ganglia are presented, demonstrating the dramatic reduction in radiation dose to the pyramidal tract and supporting the anticipated benefits in terms of radioprotection, and avoidance of post-radiosurgical deficits.
Finally the neurotrauma section presents the clinical results from a prospective study on an innovative device for non-invasive monitoring of intracranial pressure, a tool that given the high reliability demonstrated in this research might find a role in preclinical or neurointensive care settings and reduce the need for serial neuroimaging in traumatic brain injured patients.
The last chapter concludes this thesis duly outlining some forecasts and supporting literature for the widespread application of bioengineering enhanced solutions in neurosurgical theatres, wards or outpatient clinics
Coronary blood metabolomics fingerprint differentiates healthy subjects from patients with stenosing or microvascular ischemic disease
Get PDFBackground. Endothelium is a key variable in the pathogenesis of atherosclerosis and its
complications, particularly coronary artery disease (CAD). Current evidence suggests that
endothelial status may be regarded as an integrated index of individual atherogenic and
atheroprotective factors. Therefore, interplay between circulating factors and properties of the
local endothelium may be critical for the development of atherosclerosis. Metabolomics
(MBS) is the study of the metabolic profile of small molecules and provides a functional view
of the studied organism.
Objectives: to verify whether MBS was capable to detect the presence of differences in
coronary microenvironment associated to different manifestations of CAD
Methods. A 1H-NMR based MBS analysis was performed on coronary blood samples of 23
patients with indication to coronary angiography; those with evidence of myocardial ischemia
formed the case group, further divided into stenotic disease (SD group; N = 13) and absence
of stenosis (microvascular disease-Micro Group; N = 5 ), while those with no evidence of
ischemic heart disease (dilated cardiomyopathy, valvular diseases) constituted the control
group (N=5).
Results. An OPLS-DA model was applied to the whole dataset. Samples are clearly separated
into the three groups, indicating 3 different metabolic fingerprints. In comparison with
Controls, Micro patients showed a higher content of 2-hydroxybutirate, alanine, leucine,
isoleucine, N-acetygroups, and a lower content of creatine/phosphocreatine, creatinine and
glucose, whereas SD patients were characterized by higher levels of 3-hydroxybutirate,
acetate and a lower content of 2-hydroxybutirate. Finally, Micro patients compared to SD
Group showed a higher content of 2-hydroxybutirate, alanine, leucine, N-acetygroups, and a
lower content of 3-hydroxybutirate and acetate.
Conclusions. Our findings seem to suggest that specific coronary microenvironments are
associated with different development and pathological expression of atherosclerotic disease,
as resulted by the interact of pre-determined characteristics of endothelial cells (i.g. genetic,
epigenetic) with cardiovascular risk factors
La trasparenza pubblica nell’era Open Data. Studio comparato Italia-Francia
Get PDFObjects, medium, sources, governance, content, actors, purposes and forms of public transparency are experiencing a
rapid and profound evolution, which transcends national borders, and depends on the interaction between political,
technological, legal and socio-cultural drivers. This happens when transparency exploiting the Open Government Data
means and falls under the Open Government framework.
Through the Italian and French legal systems, this thesis aims to highlight the recent advancements in public transparency.
At first, we will look at the interplay between the concepts of transparency and openness, to identify the legal issues raised
by the disclosure of public data. Subsequently, we will turn to the supranational context, which plays a key role in
developing guidelines, standards and recommendations. A special place will be reserved to the right (and political) of the
European Union. In the second part, we will analyse the above-mentioned legal systems, which are actively engaged in
the wider reform of their Public Information Acts, within the framework of multi-stakeholder initiatives, such as the Open
Government Partnership.
On the whole, we will see how the shift from “transparency through documents” ” to “transparency through data challenges the public action models
Il valore della partecipazione per l'effettività della cittadinanza amministrativa digitale
Get PDFParticipation in the administrative procedure is the central theme of this research work,
that is developed according to the perspective of the change between the citizen -
administration relationship, leading thread of the whole investigation.
The theme chosen, at first, pushes to draw the attention to the "administrative change",
starting from the consideration that the organizational and functional complexity typical
of the multi-classes State, linked to the need of the new administration's legitimacy, has
laid the basis for a general rethinking of the administration as “public interest care
function”.
In this perspective, the introduction of the law 241/1990 marks a fundamental turning
point in the history of administrative law, not only because it introduces important
democratic safeguard values that arise as a corollary of the constitutional principles of
impartiality and efficiency, but above all because “lays the foundation” for a new
relationship between government and citizen, in which the latter "undresses" the figure of
a subject to become a resource available to the administration.
In emphasizing the central role of the citizen bearer of views, interests and values within
the intervention areas normatively recognized in general by law 241/1990, the
investigation focuses on the "conquest" of the administrative citizenship, which makes
the concepts of participation, inclusion and sharing the paradigms of the new
organizational and management culture of public administration.
On these fundamental interpretations is built the research, which dedicates the first part
of the work to the analysis of the participatory institutions contemplated in the Law
241/1990, with a careful look at the ties of these with the "two souls" of the
administrative procedure, guarantee and efficiency, that precisely with reference to the
participation show all their complexity and criticality.
Including the legal and social relevance of “innovation” related to the law 241/1990, at a
later time, it is addressed the issue of computerization of public administrations as a
process of modernization, which requires a “structural change”, aimed at completing the
process of administrative reform that makes the improved dialogue between
administration and citizen his main strength.
In this perspective, the research continues analysing the implications of the
computerization process on participation, not so much related to new institutions as to
novel ways of intervention of the citizen in the digital administrative procedure.
Finally, this research attempts to investigate the strengths and weaknesses of the
telematics relationship between government and citizen, which, although becoming the
occasion of birth of new rights and while acknowledging an active role of the citizen in
the reform process, too often it collides with the unsatisfactory level of “digital
development” of our country.
Leaving to the following any other clarification, represents aspiration of the writer the
opening to interesting and critical insights on what is, nowadays, the most profound
sense of being digital administrative citizens
Man, plant remains, diet: spread and ecology of Prunus L. in Sardinia
No full textArchaeobotany offers the opportunity to explore the various practices related to the use of wild plants and understand how these have been selected for domestication. The identification of wild and cultivated plants could facilitate the understanding of the role they have in the subsistence economy and how this is strictly related to dietary habits.
The main goals of this thesis are to interpret and understand the relation between human communities and the exploitation of plant resources in the past, thus understanding agricultural and alimentary behaviors in the present time.
The genus Prunus has been selected because understudied in Sardinia from the archaeobotanical point of view but fairly widespread in the Mediterranean archaeological contexts.
The application of image analysis technique for an adequate definition of the endocarp morpho-colorimetric and morphometric parameters represents an important diagnostic factor in the Prunus taxonomy studies and consequently may be helpful for the improvement of the management and in the enhancement of ancient fruit. The study of traditional varieties aims to create models of development, recovery and enhancement of ancient fruit. Also sets the basis for proposals for the recovery of cultural traditions and local economies.
For the first time, it was possible to investigate about the morphology and morphometry of P. domestica endocarps of traditional local varieties from Sardinia. Endocarp morpho-colorimetric features, EFDs and Haralick’s descriptors obtained by image analysis allowed to implement a statistical classifier able to identify and classify the studied varieties of P. domestica, identifying plausible synonymy groups and confirming that the endocarp retain some characters directly related to the fruit skin color.
The discovery of well-preserved waterlogged endocarps of P. domestica from the Phoenician-Punic settlement of Santa Giusta could be evidence that the introduction of primitive cultivated forms of plums in Sardinia have been introduced by the Phoenicians people. Moreover, these endocarps represent the oldest findings and they are the oldest evidence of cultivated plums in the western Mediterranean Basin.
Finally, for the first time, it was possible to investigate through image analysis system about the morphology and morphometry of archaeological P. spinosa endocarps from Sardinia. These sites are currently the only finds of P. spinosa remains in waterlogged conditions documented in Sardinia by archaeological sources. Thanks to image analysis system it was possible to understand the hypothetical origin
Optimization of microwave devices
Get PDFThis thesis deals with the optimization techniques for the improvement of the microwave
devices performance. In particular, the technique proposed considers the Particle Swarm Optimization
algorithm and applies such an algorithm to different devices. Different techniques
are developed to connect the optimization with an electromagnetic analysis tool. In the first
method the algorithm has been connected to a numerical technique for the evaluation of the
device performance (FDFD). The second technique consists on the integration of the algorithm
with a 3D Simulation CAD (HFSS, CST). The microwave devices under test are a ridge
waveguide (in different configurations), a resonant cavity, a waveguide impedance transformer
and an electromagnetic band gap structure. Both the approaches result to be effective for the
purpose even in the event that a constraint between conficting requirements is requested
Application of NMR-based metabolomics techniques to biological systems: a case study on bivalves
Get PDFIn the past years, metabolomics has progressed greatly, providing a reliable and high-throughput approach particularly feasible for the study of complex biological systems. Indeed, thanks to the development of powerful analytical methods capable of screening a large number of chemical compounds in a sample, nowadays metabolomics plays an important role in gaining biological insights toward the influence of internal (genetic and developmental) and external (environmental) factors on phenotypes.
The work presented in this Ph.D. thesis shows examples of applications of NMR-based metabolomics to the study of bivalves, facing challenges of interest in both food and environmental sciences. The outcome of such studies yield insights, at molecular level, into several aspects concerning the impact of different storage conditions on shellfish quality and the effect of natural and anthropogenic environmental stressors on bivalves’ metabolic profiles.
Firstly, the effect of different cold storage conditions on the hydrosoluble chemical components of Mytilus galloprovincialis (Lamarck, 1819) was investigated for the first time by NMR-based metabolomics. The data revealed substantial time-related changes in the metabolic profiles of mussels stored at 0 °C and 4 °C. The observed biochemical modifications were in good agreement with the microbiological quality of samples, reflecting changes in their microbial loads. These results confirmed the potential use of metabolomics as a reliable method to assess seafood freshness.
Secondly, a metabolomic approach was also applied to study the effect of short-term exposure to heavy metals on two different clams’ species: Ruditapes decussatus (Linnaeus, 1758) and Ruditapes philippinarum (Adams & Reeve, 1850). Heavy metals are considered to be among the most harmful pollutants that can contaminate marine environments. The toxicity of trace metals gives rise from their persistent nature which lead to environmental accumulation. Given the high accumulation rates associated with their filter feeding attitude, bivalves mollusks are considered to be feasible monitoring organisms and are widely used in biomonitoring programs. R. decussatus and R. philippinarum, two bivalves’ species widely distributed along the Italian coasts, were selected in this Ph.D. project for assessing lead and zinc effects on their metabolic
profiles. The results evidenced a sensible short-time metabolic response upon metal exposure, pointing out a main variability in the content of amino acids and organic osmolytes in relation to both metal nature and bivalve species. These findings show that NMR-based metabolomics has the required sensitivity and specificity to gain insights into the biochemical consequences arising upon heavy metals exposure, providing thus a useful tool for the identification of putative biomarkers as fast and sensitive indicators of contaminant-induced stress.
Finally, 1H NMR-based metabolomics was applied with the aim to assess the effects of seasonal change on Ruditapes decussatus metabolic profile. The results of the present study demonstrated that the combined use of advanced multivariate statistical techniques with NMR spectroscopy is a feasible approach to discriminate specimens of R. decussatus according to the sampling season. Moreover, the sensitivity of this analytical tool allowed the individuation of those metabolites whose relative amount significantly varied according to seasonal change (alanine and glycine), paving the way for further investigations that would contribute to achieve additional insights on bivalves’ bio-ecological framework
Complex formation equilibria of ligands with metal ions of biomedical interest
Get PDFIn a healthy situation, the body is provided with homeostatic mechanisms and buffers to maintain physiological concentrations of free metal ions, thus preventing their abnormal decompartmentalization, release and trafficking. The main reasons for the anomalous accumulation of non-essential metal ions in the body are environmental exposure and administration of metallodrugs for therapy or diagnosis, which may cause competition for biometals, generation of oxidative stress and disregulation of several metal-enzyme systems. Inorganic medicinal chemistry has to deal with the introduction of metal ions in the body, but also with their removal or passivation through the use of chelators. In these terms, thermodynamics and kinetics of complex formation are very important for a correct understanding of the role of metal ions in human diseases.
During my PhD work, some new ligands were synthesized and their complex formation equilibria with toxic, essential and other metal ions of biomedical interest were studied.
In particular, some derivatives of kojic acid have been synthesized and their protonation and chelating properties toward the target metal ions Fe3+ and Al3+, and the two essential Cu2+ and Zn2+ have been characterized. Furthermore, the complex formation equilibria of some drugs actually in clinical use with the essential metal ions Cu2+ and Zn2+ were studied to give evidence of their possible implications in copper chelation. Moreover, the tyrosinase inhibitory properties of the kojic derivative[1] (5-hydroxy-4-oxo-4H-pyran-2-yl)methyl3-({[(5-hydroxy-4-oxo-4H-pyran-2yl)methoxy]carbonyl} amino)propanoate and its complex formation equilibria with copper have been studied, since the inhibitory effect may result from the interaction with copper ions in the active center of the enzyme.
This thesis is divided in an Introduction, dedicated to a description of metals, to their chemistry and their overload or deficiency, to chelation therapy, to the characteristics of chelators for metal overload treatment and to the improvements induced on some pathological conditions in diabetic patients. Further attention is devoted to tyrosinase inhibition and radiopharmaceutical labelling. An Experimental part describes the synthesis of new chelators and the methods used for a complete characterization. In the section Results and Discussion the determination of protonation constants for all ligands, together with that of their complex formation constants with metals of interest like Fe3+, Al3+, Ga3+, Cu2+ and Zn2+, is presented, in order to evaluate their therapeutic application in metal overload diseases. Complex stability studies of two new ligands with lanthanum to be used in the treatment of bone disorders are also presented as a part of a collaboration during my three month period at the University of British Columbia, Vancouver-Canada. A brief section Conclusions summarizes the presented results
Colloidal CoFe2O4-based nanoparticles for Magnetic Fluid Hyperthermia
Get PDFIn the field of biomedicine, important issues to address are the early-stage diagnosis and targeted therapies. Since the last two decades, magnetic nanoparticles have been proposed as potentially powerful due to their unique chemical-physical properties. Magnetic nanoparticles can be applied in a wide variety of biomedical fields from the magnetic separation and Magnetic Resonance Imaging (MRI) to drug delivery and Magnetic Fluid Hyperthermia (MFH).1 In particular, MFH is based on the heat released by magnetic nanoparticles subjected to an alternate external magnetic field. Among the different material features affecting the hyperthermic efficiency, the magnetic properties are clearly the most important. Therefore, the optimisation of the magnetic properties, aimed to increase the heating ability and to reduce the magnetic material dose to be inserted in the human body, is still an active research field. In 2013 alone, 682 works have been published in the literature on the topic of magnetic hyperthermia.2
Despite cobalt toxicity, cobalt-containing materials and especially cobalt ferrite nanoparticles have been proposed as promising heat mediators due to its high anisotropy.3–13
In this thesis, the results obtained on two different systems, designed with the idea of studying the effect on the hyperthermic properties of proper tuning of the magnetic properties, are presented. Both the sets of samples are based on cobalt ferrite nanoparticles. The first strategy consists on the substitution of cobalt ions with zinc ones with the aim of tuning the magnetic properties of the system and, at the same time, decrease the toxicity of the material. The second way is on the contrary represented by the coating of cobalt ferrite cores by means of biocompatible or less toxic isostructural phases (i.e. magnetite/maghemite or manganese ferrite)