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Heavy ion charge exchange reactions and their link with single and double beta decays
No full textWe performed theoretical studies on Heavy ion charge exchange reactions, at low energies, focusing on the interplay between nuclear structure and reaction dynamics. Such studies allow also to enlight the existence of a relation between Heavy ion double charge exchange (HIDCE) cross section at forward scattering angles and double beta () decay nuclear matrix element (NME) of the target or projectile nucleus considered. HIDCE reactions can be described as a sequence of two single charge changing processes, which can be correlated or not, thus mimicking and decays, respectively. The dominance of the former mechanism would allow to gain information on NME, thus in turn allowing to determine neutrino Majorana mass with a significant accuracy, if such weak decay were observed
Coupled Molecular Dynamics and Finite Element Methods for the simulation of interacting particles and fields
No full textThe dynamical simulation of many particle systems is currently a widespread technique in many fields: e.g. nuclear and atomic physics, computational material science, computational chemistry, molecular biology and pharmacology. Under the locution Molecular Dynamics (MD) we can regroup a variety of approaches and numerical codes, whereas the commonalities are: 1) the atomistic (or nuclear) resolution (i.e. particles are atoms or nucleons), 2) the force derivation, starting from the systems configuration, through semi-classical (also called semi-empirical) or quantum mechanics based theoretical frameworks, 3) the (generally explicit) numerical integration of the Newton-like equations of the motions to simulate the system kinetics. Within this scheme methodology variations can be found in the literature, but it is undoubtedly valid to qualify the MD meaning in the field of the scientific computation.
The general scope of this Thesis work is the extension of the MD methods to the study of kinetics of larger particle (i.e. from mesoscopic dimensions and above), where effective particle-particle interactions are mediated by a field evolving self-consistently with the many particles system. This objective is mainly motivated by the applications of the method to control and predict the manipulation of mesoscopic (electrically) neutral particles by means of electromagnetic (e.m.) interactions: i.e. exploiting the so called dielectrophoresis (DEP) phenomena in the systems of electromechanical particles (EMPs). This is the specific case of study here considered, but in principle the methodology can applied after suitable adaptation to also other systems
Semi-classical and Quantum corrected Hydrodynamic models
No full textSemi-classical hydrodynamic models for charge transport in graphene have been presented. They are deduced as moment equations of the semiclassical Boltzmann equation with the needed closure relations obtained by resorting to the Maximum Entropy Principle. The models differ in the choice of the moments to assume as basic field variables. Both linear and nonlinear closure relations are analyzed. The validity of all the semi-classical models presented is assessed by comparing the mean values of energy and velocity with those obtained from the direct solutions of the Boltzmann equation in the simple case of suspended monolayer graphene. It has been found that it is crucial to include- among the field variables- the deviatoric part of the stress tensor to maintain a good accuracy in a wider range of applied electric fields. Moreover apparently the results confirm that the nonlinearity is not critical for accuracy.
Then, to take into account quantum phenomena, in the last part of this work a quantum hydrodynamic model for charge transport in graphene is derived from a moment expansion of the Wigner-Boltzmann equation. The needed closure relations are obtained by adding to the semiclassical ones quantum corrections based on the equilibrium Wigner function. The latter is obtained from the Bloch equation by taking into account the appropriate energy band of graphene. Furthermore, quantum energy-transport and drift-diffusion models have been formally derived from the quantum hydrodynamic equations in the long time asymptotic limit. In analogy with the semiclassical case we are confident that the energy-transport and drift-diffusion models have mathematical properties which allow an easier numerical treatment
Rotazione paleomagnetiche lungo faglie trascorrenti nello Yunnan (Cina): approccio paleomagnetico e strutturale
No full textData from this study report on the paleomagnetism of sedimentary and volcanic rocks cropping out near the Gaoligong and Ailao-Shan Red River Shear Zones. Fifty paleomagnetic sites were analyzed collecting 503 samples, during the first year of Ph.D., at variable distances (up to ca. 25 km) from mylonites exposed along the Gaoligong fault. Jurassic-Cretaceous red bed sites yield systematic CW rotations with respect to Eurasia reaching the peak values of 176 degree close to the fault, and progressively decrease moving eastward, up to be virtually annulled ca. 20 km E of mylonite contact. West of the Gaoligong fault, Pliocene-Holocene sites from the Tengchong volcanic field do not rotate. Thus, data show that the Gaoligong Shear Zone activity yielded significant CW rotations that were likely coeval to the main Eocene-Miocene episodes of dextral fault shear. The Gaoligong zone rotation pattern conforms to a quasi-continuous crust kinematic model, and shows blocks of less then or equal 1 km size close to the fault, which become bigger moving eastward. Rotation and width values of the rotated-deformed zone translate to a 230-290 km Gaoligong Shear Zone dextral offset, which shows that fault shear plays a significant role in Indochina CW block rotation.During the second year of Ph.D., forty-four Triassic-Cretaceous sites (425 samples) were collected at both sides of the Ailao-Shan Red River Shear Zone (ARRSZ), within the Chuandian, Lanping and Northern Simao blocks. Nearly all sites yielded measurable and stable magnetization components, but magnetization acquisition timing was different in the three blocks. Sites from the Chuandian block show a normal polarity and were remagnetized after folding. In the northern Simao block the magnetization was acquired before folding (about 33 Ma ago), but the ubiquitous normal polarity in Jurassic-Cretaceous sites suggests a pre-folding magnetic overprint. The data show variable and different rotation that do not display evidence of a rigid block rotation, but suggest that the northern Simao block is made of small (few km size) sub-blocks rotating CW, separated by non-rotating domains of similar size. Finally, a high-temperature (640-680 degree C) magnetization component suggests a similar rotational behaviour (CW-rotating and non-rotating sub-blocks) in the centre of the Lanping block. Conversely, a 300-640 degree C component was later acquired at 28% unfolding and subsequently underwent no rotation. The sites close (less than 25 km) to the ARRSZ yield great rotations of nearly 180 degree, which confirm past occurrence of significant strike-slip shear along the ARRSZ itself. Conversely, sites located at 10-15 km distance from the Chongshan Shear Zone show ca. 90 degree CCW rotations that imply a left-lateral shear along the fault zone, consistently with recent geological evidence. Summarizing, data from my Ph.D. study, together with previous evidence of rotations documented both near the fault zones and within the blocks themselves, show that crustal deformation of the Yunnan is extremely complex and still puzzling. The Baoshan and Lanping-Simao blocks underwent strong internal deformation and were likely fragmented in smaller independent sub-blocks whose kinematics and tectonics are still a matter of speculation
Automated Reasoning via a Multi-sorted Fragment of Computable Set Theory with Applications to Semantic Web
No full textSemantic Web is a vision of the web in which machine-readable data enables software agents to manipulate and query information on behalf of human agents. To achieve such goal, machines are provided with appropriate languages and tools. Investigating new technologies which can extend the power of knowledge representation and reasoning systems is the main task of my research work started by observing the lack of some desirable characteristics concerning the expressiveness of semantic web languages and their integration with some features of rule-based languages, arisen with the study of some application domain during the draft of my bachelor thesis.
Specifically in this dissertation, I consider some results of \emph{Computable Set Theory}, a research field rich of several interesting theoretical results, in particular for what concerns multi-sorted and multi-level syllogistic fragments, in order to provide a novel powerful knowledge representation and reasoning framework particularly devoted to the context of Semantic Web.
For this purpose, I use a syllogistic fragment of computable set theory called \flqsr, admitting variables of four sorts and a restricted form of quantification over variables of the first three sorts, to represent and reason on expressive decidable \emph{description logics} (DLs) which can be used to represent ontological knowledge via Semantic Web technologies. I show that the fragment \flqsr allows one to represent an expressive DL called \dlss (\shdlss for short) and its extension \dlssx (\shdlssx for short). The DL \shdlssx admits, among other features, Boolean operations on concepts and roles, data types, and product of concepts. Moreover, \flqsr provides a unique formalism which combines the features of the DL \shdlssx with a rule language admitting full negation and subject to no safety condition. I show that \flqsr can be used to represent a novel Web Ontology Language (OWL) 2 profile, and hence can be used as reasoning framework for a large family of ontologies. Then, I study the most widespread reasoning tasks concerning both \shdlssx-TBoxes and \shdlssx-ABoxes. In particular, I consider the \emph{Consistency Problem} of a \shdlssx-knowledge base (KB), the \emph{Conjunctive Query Answering} (CQA) for \shdlssx, which provides simple mechanism allowing users and applications to interact with data stored in the KB, and the \emph{Higher-Order Conjunctive Query Answering} (HOCQA) for \shdlssx, a generalization of the CQA problem admitting three sorts of variables, namely, individuals, concepts, and roles. The decidability of the above mentioned problems are proved by resorting them to analogous problems in the context of the set-theoretic language \flqsr by means of a suitable mapping function from axioms and assertions of \shdlssx to formulae of \flqsr.
Then, I provide a correct and terminating algorithm for the HOCQA problem for \shdlssx based on the \ke\space system, a refutation system inspired to the Smullyan's semantic tableaux, giving also computational complexity results. The algorithm also serves for the consistency problem of \shdlssx-KBs and for other reasoning tasks which the HOCQA problem can be instantiated to.
I also introduce an implementation in C++ of the algorithm thus to provide an effective reasoner for the DL \shdlssx which admits ontology serialized in the OWL/XML format
Studio dei bacini idrici superficiali siciliani per la valutazione del rischio sulla salute e sull'ambiente
No full textDue to the population growth, urbanization and economic development, demand for freshwater in urban areas is increasing throughout Europe. At the same time, climate change and pollution are also affecting the availability of water supplies. Sicily, a southern island of Italy, suffers from a growing strong water scarcity and drought. The freshwater basins of Sicily are not well characterized and classified. In last decades, in Sicilian freshwater surface reservoirs several Planktothrix rubescens and Microcystis aeruginosa blooms have reported. A further actual worldwide problem for all surface freshwaters basins is the increasing of heavy metals concentrations in their waters.
Aims of this research doctoral project were: a) perform a census of Sicilian natural and artificial freshwater basins and identify which of these are suitable for use for drinking purposes; b) carry out a risk assessment related to presence of Microcystins and heavy metals (As, Pb, V, Cd, Al); c) evaluate the waters toxicity through ecotoxicological bioassays and verify if they would be sensitive and reliable to investigate on toxicity of mixtures of heavy metals and Microcystins.
It was carried out the monitoring of 15 surface basins, among the 30 existing in Sicilian territory, through seasonal chemical, physical and microbiological analysis of the waters such as required by Italian law, the Legislative Decree 152/2006. Moreover, it was performed speciation of cyanobacteria community, cell counting, and PCR analysis. Finally, it was carried out acute (V. fischeri), subacute (T. platyurus) and chronic (D. magna) ecotoxicological assays.
There is much reassurance about quality chemical status of basins. In fact, there are no heavy metals above the reference values. Only Aluminum and Iron are present often in large concentration. The high levels of total nitrogen and phosphorus give information about the inflow of partially or completely untreated urban and rural wastewater in all basins.
However, in 50% of examined dams, there were the presence of several cyanobacteria species. In particular, it was detected cyanobacteria bloom in Disueri in period between July and September 2017. Microcystis sp. and Cylindrospermopsis raciborskii were detected (108 and 107 cell/L, respectively) and by mid-August were replaced by Anabaenopsis sp. and Plankthotrix rubescens, still growing in mid-September (107 and 106 cell/L, respectively). MCs concentrations in every samples were low, in agreement with the lack of qualitative amplification of the mcyE gene.
The distance biplot of PCA showed that Disueri, Pozzillo, Trinità and Arancio dams are located near together and are strongly influenced by N, Fe, Al, V, Mn, F, Mn, Cl, pH, Ca and Nitrite. In recent past, all these dams were currently affected by harmful algal bloom.
V. fischeri and D. magna assays seem to respond to the number of cyanobacteria cells rather than toxins concentrations. Instead, T. platyurus assay show a significant positive relationship between MCs concentrations measured by ELISA test.
In conclusion, the chemical quality of Sicilian surface freshwaters catchments is good and it could be improved it with a better treatment and management of wastewaters got into the surface waters. Concerning the Microcystins contamination, since in every analyzed sample the concentration was below the WHO reference value for drinking waters (1 ug/L) it seems not to be a high and worrying risk for human and environmental health in the brief time.
The simultaneous execution of V. fischeri and T. platyurus bioassays could favor the monitoring of waters both economically and technically.
PCA analysis seems to be reliable to be used as predictive models for cyanobacteria growth.
Finally, respecting these describes condition, it would be possible the use of waters of all monitored basins as drinking after an adequate treatment according to Italian Legislative Decree 152/2006
Linee guida e regime disciplinare del professionista sanitario strutturato.
No full textLa ricerca - condotta durante il triennio di partecipazione al XXXI ciclo di dottorato in Scienze Politiche e Sociali - analizza il processo di formalizzazione, introdotto dai recenti interventi riformatori, in materia di responsabilità sanitaria, da ultimo la legge 8 marzo 2017, n. 24, «Disposizioni in materia di sicurezza delle cure e della persona assistita, nonché in materia di responsabilità professionale degli esercenti le professioni sanitarie», al fine di cogliere le possibili ripercussioni in ambito disciplinare nei confronti dell esercente le professioni sanitarie strutturato con qualifica dirigenziale.
Obiettivo essenziale dell attività di ricerca è quello di verificare se alla luce delle innovazioni legislative, la violazione delle linee guida sia idonea ad instaurare un procedimento disciplinare a carico del professionista sanitario inadempiente, a prescindere dalla concreta verificazione di un danno al paziente.
Questa prospettiva muove da una nuova configurazione dell interesse datoriale, il quale non appare più circoscritto all esecuzione della prestazione sic et simpliciter, ma è strettamente collegato all organizzazione della struttura che si estrinseca anche, e soprattutto, mediante la formazione di atti di indirizzo e strumenti contrattuali connessi alle linee guida formalizzate secondo le indicazioni della l. 24/2017.
Nell ambito di una prestazione complessa, così come quella sanitaria, l esecuzione tecnica di una prestazione sanitaria, oggi altamente standardizzata, si intreccia con gli aspetti più squisitamente organizzativi imposti dalla struttura, mediante l emanazione di ulteriori linee guide, diventando un unicum inscindibile per valutare il corretto adempimento della prestazione sanitaria.
Di conseguenza, anche il profilo disciplinare ha subìto, di fatto, una metamorfosi, non chiaramente esplicitata nella novella legislativa introdotta, ma desumibile, come si avrà modo di approfondire in prosieguo di trattazione, da un interpretazione coerente con l impianto della riforma.
Il tema è osservato da una pluralità di prospettive, tratte non solo dall esperienza didattica universitaria ma, altresì, dall esercizio della professione forense in ambito lavoristico, che ha fornito l opportunità di scandagliare numerosi procedimenti disciplinari, nonché le prassi operative seguite all interno di amministrazioni sanitarie pubbliche e private
Sistemi e misure di protezione internazionale dello straniero tra ordinamento italiano ed europeo, indagine sui modelli di valutazione del grado di personalizzazione del rischio.
No full textLa tesi affronta il tema del risk assessment nel sistema della protezione internazionale dello straniero richiedente asilo.
La disciplina giuridica dei rifugiati, com è noto, non considera espressamente le modalità di accertamento del rischio di subire una persecuzione o un danno grave. Eppure, la valutazione del rischio è essenziale nel giudizio prognostico teso al riconoscimento della protezione internazionale.
In tale contesto, la tesi propone una lettura della normativa esistente in materia attraverso la rappresentazione di un paradigma volto a verificare le possibili situazioni di rischio che tipicamente si presentano all organo giudicante nell esame delle domande di asilo.
Verificati i profili di tensione che derivano dall applicazione concreta del paradigma del rischio , la ricerca si focalizza sull ipotesi specifica di risk assessment nei confronti delle donne richiedenti asilo per ragioni legate a situazione di violenza di genere . A tal fine vengono analizzati alcuni casi scelti sul rischio di mutilazioni genitali femminili, di tratta con finalità di sfruttamento sessuale e di matrimonio forzato sulla base dell appartenenza della vittima ad un particolare gruppo sociale. Attraverso un analisi empirica e comparativa della prassi giurisprudenziale interna di alcuni Stati membri dell UE, emergono gli orientamenti e gli approcci delle giurisdizioni interne utili ad individuare alcuni specifici fattori di rischio che consentono di concedere la protezione internazionale, fattori particolarmente connessi ai diritti economici, sociali e culturali delle donne richiedenti asilo
Cooperating Smart Objects in IoT Infrastructures for Context-Aware Applications
No full textIl lavoro svolto durante il mio Dottorato di Ricerca si e' focalizzato su Smart Object cooperanti all'interno di infrastrutture IoT, sfruttanti le tecnologie indoor e outdoor appena mensionate per la realizzazione di applicazioni Context-Aware.
Questa tesi presentera' i concetti dell'Internet of Things e diverse questioni ancora irrisolte, o parzialmente risolte, insieme ai lavori sviluppati durante questi anni, nei quali ho cercato di applicare i concetti dell'IoT in diversi ambiti quali Citta' Intelligenti (Smart Cities) ed Ambienti Intelligenti (Smart Environment).
Il primo capitolo di questa tesi introdurra' l'Internet of Things come nuovo paradigma ed miglioramento della qualita' della vita. Verranno messe in evidenza le origini dell'IoT e il suo sviluppo attraverso l'introduzione di nuove tecnologie.
Questo capitolo introduttivo mostrera' l'incremento delle capacita' degli oggetti ordinari attraverso l'utilizzo dei concetti dell'IoT, e presentera' diversi domini applicativi in cui questi dispositivi vengono posti.
Inoltre, il primo capitolo introdurra' l'importante concetto di Context, lo sviluppo delle applicazioni Context-Aware per la realizzazione di servizi personalizzati all'interno degli ambienti smart, la realizzazione di reti IoT che presentano molti punti in comune con le reti informatiche tradizionali, ed un insieme di problematiche ancora aperte che rappresentano sfide per la comunita' di ricerca.
Gli altri capitoli riporteranno una serie di lavori sviluppati durante l'attivita' di Dottorato di Ricerca, e che hanno come obiettivo la copertura di diversi domini IoT fornendo servizi in grado di aumentare l'esperienza utente all'interno degli ambienti smart.
Questi lavori hanno l'obiettivo di fornire soluzioni per citta' (Capitolo \ref{chap:smartparking}, \ref{chap:baas}), abitazioni e uffici (Capitolo \ref{chap:CooperativeObjectsChapter}), e musei (Chapter \ref{chap:smartworks}).
L'obiettivo comune e' mostrare come l'IoT possa rappresentare un valore aggiunto nella vita delle persone.
Le persone hanno mostrato un grande interesse nei confronti della tacnologia, ed un numero non indifferente di utenti sono gia' forniti da una serie di dispositivi smart (come gli smartphone). Per questo motivo, penso sia molto utile sfruttare questi dispositi ed i loro sensori per la realizzazione e la personalizzazione di servizi, senza la necessita' di utilizzare ulteriori costose infrastrutture, o fastidiosi sensori addizionali.
Infine, questa Tesi introdurra' un sistema maggiormente complesso e costoso, ovvero un sistema per il monitoraggio della qualita' dell'aria, che ha come obiettivo quello di realizzare un report dell'inquinamento attraverso un applicazione web, raccogliendo informazioni di contesto dell'utente per fornire dei consigli su quali strade utilizzare o quali posti raggiungere evitando l'inquinamento
Applicazione di controlli non distruttivi nella gestione delle infrastrutture di trasporto. Specifiche prestazionali di controllo della qualità in costruzione e manutenzione
No full textNowadays, in Transport Asset Management, there is the need to identify measures to guarantee high levels of performance over time. The application of Non-Destructive Techniques, through high-efficiency equipment, turns out to be an optimal solution to ensure the quality of transport infrastructures.
Asset Management take into account the importance of monitoring the performance characteristics of the transport infrastructures and QA/QC performance-based contracts specifications in order to guarantee the preservation of environmental, social and economic resources, as well.
This study consists of two parts of research activity: in field tests and numerical simulations.
The first part consists of in situ experimental activities to investigate both road and rail transport infrastructures. The tests have shown the versatility of high-performance instruments, such as FWD, LWD, GPR and ARAN, in railway monitoring, in the evaluation of ballast conditions and sleeper/ballast interaction, and also in the reuse of volcanic ashes that after stabilization can be used in road subbase layers. The high-efficiency equipment allow a faster execution of the tests with the possibility of a higher number of measurements, the combination of several instruments at the same time with a continuous mapping of the infrastructures, performance measures and a significant cost reduction.
In the second part, the study focuses more specifically on road pavements. Considering several flexible pavements pulled out from the Italian Catalog, numerical simulations of FWD tests were carried out in the hypothesis of multilayer elastic theory with the aim to develop performance-based criteria and specifications for QC of pavement construction work.
The results allow to estimate effects of structural deficits in the perspective of future performance and Life Cycle Cost Analysis in order to quantify penalties to restore expected higher maintenance costs