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An inamimate reasoner
No full textIn this thesis we proposed new neural architectures and information theory approaches. By means of wavelet analysis, neural networks, and the results of our own creations, namely the wavelet recurrent neural networks and the radial basis probabilistic neural networks,we tried to better understand, model and cope with the human behavior itself. The first idea was to model the workers of a crowdsourcing project as nodes on a cloud-computing system, we also hope to have exceeded the limits of such a definition. We hope to have opened a door on new possibilities to model the behavior of socially interconnected groups of people cooperating for the execution of a common task. We showed how it is possible to use the Wavelet Recurrent Neural Networks to model a quite complex thing such as the availability of resources on an online service or a computational cloud, then we showed that, similarly, the availability of crowd workers can be modeled, as well as the execution time of tasks performed by crowd workers. Doing that we created a tool to tamper with the timeline, hence allowing us to obtain predictions regarding the status of the crowd in terms of available workers and executed workflows. Moreover, with our inanimate reasoner based on the developed Radial Basis Probabilistic Neural Networks, firstly applied to social networks, then applied to living companies, we also understood how to model and manage cooperative networks in terms of workgroups creation and optimization. We have done that by automatically interpreting worker profiles, then automatically extrapolating and interpreting the relevant information among hundreds of features for each worker in order to create workgroups based on their skills, professional attitudes, experience, etc. Finally, also thanks to the suggestions of prof. Michael Bernstein of the Stanford University, we simply proposed to connect the developed automata. We made use of artificial intelligence to model the availability of human resources, but then we had to use a second level of artificial intelligence in order to model human workgroups and skills, finally we used a third level of artificial intelligence to model workflows executed by the said human resources once organized in groups and levels according to their experiences. In our best intentions, such a three level artificial intelligence could address the limits that, until now, have refrained the crowds from growing up as companies, with a well recognizable pyramidal structure, in order to reward experience, skill and professionalism of their workers. We cannot frankly say whether our work will really contribute or not to the so called "crowdsourcing revolution", but we hope at least to have shedded some light on the agreeable possibilities that are yet to come
Citrus Limonoids: Functional Chemicals in Agriculture and Foods
No full textThe search for limonoids started long back when scientists started looking for the factor responsible for bitterness in citrus. Studies showed that limonoids are highly oxygenated, modified terpenoids and have recently attracted attention because compounds belonging to this group have exhibited a range of biological activities like insecticidal, insect antifeedant and growth regulating activity on insects as well as antibacterial, antifungal, antimalarial, anticancer, antiviral and a number of other pharmacological activities on humans.
Based on this premise this paper has focused on technological, healthful and chemical aspects of the limonoids.
-TECHNOLOGICAL APPROACH:
Based on a project titled Enhancement of bioactive compounds isolated from agro-industrial wastes financially supported by the Italian Ministry of Education, a Sicilian juice company wanted to assess the possibility of transforming the waste by-product of citrus processing (pastazzo) in a resource trying to turn it into dietary fiber. To do that, the company has inserted a debittering line to the plant using an alkaline aqueous solution in order to extract flavanones and limonoids.
In the present paper the operational conditions of debittering were evaluated and optimized by determining the limonin content of samples from various stages of fiber production; It was also verified if the recovery of limonin extracted was economically viable.
-HEALTHFUL AND ORGANOLEPTIC CHARACTERISTICS:
It has been established that U.S. producers are turning to organic farming system as a potential way to lower input costs, decrease reliance on nonrenewable resources, capture high-value markets at premium price, and boost-farm income. Organic production agriculture is characterized by inputs of biologically (non-synthetic) based fertilizers and pest management practices that are sustainable.
In order to understand if the market source contributes to differences in bioactives content, the bio-actives content of fruits obtained from farmers' markets was compared to the content found in fruit purchased from retail grocery stores. Organoleptic properties, including Brix, TTA, color and pH were measured. Limonin, ascorbic acid and flavanoid contents were also determined.
-SYNTHESIS AND CHARACTERIZATION OF FUNCTIONAL COMPOUNDS:
Ehrlich s reagent, p-dimethylaminobenzaldehyde (DMBA) in hydrochloric acid, has a long history and is known as the coloring reagent of pyrrole. 2,3.
When a solution of limonoids is treated with p-dimethylaminobenzaldehyde in acid environment the solution immediately change to red-purple until dark blue. This reaction has named Ehrlich s reaction and the purple coloring is probably due to the presence of an adduct compound with an electron-rich trisubstituted furan ring.
In order to determine the structure of the limonin-DMBA and limonin glucoside-DMBA adducts, both compounds have been synthesized, purified and characterized. This project involves synthesis of the target compounds. MS analysis were conducted for the characterization of the isolated products
L'Accademia degli Etnei nella Catania del XVIII secolo
No full textLa tesi riguarda uno studio sull'Accademia degli Etnei di Catani
mTOR in Alzheimer's disease
No full textThe majority (>95%) of Alzheimer s disease (AD) cases are sporadic and of unknown causes. The single major risk factor for AD is aging and molecular changes that occur in the brain as a function of age may facilitate the development of AD. However, little is known as to how the aging process facilitates the development of AD.
Overwhelming evidence shows that reducing the activity of the mammalian target of rapamycin (mTOR) increases lifespan and health-span in several genetically different species. mTOR is a ubiquitously expressed protein kinase that plays a key role in regulating protein synthesis and cell growth. mTOR also is a negative regulator of autophagy induction. By simultaneously regulating protein synthesis and degradation, mTOR is key in controlling protein homeostasis, a process that is altered in AD and other proteinopathies. Another known function of mTOR signaling is the regulation of synaptic plasticity and function.
Using two widely used animal models of AD, known as Tg2576 and 3xTg-AD mice, we employed multidisciplinary approaches to dissect the role of mTOR signaling in AD. We found that genetic reduction of mTOR signaling reduced amyloid-â deposits and tau pathology and rescued memory deficits in Tg2576 mice. Mechanistically, the reduction in mTOR signaling led to an increase in autophagy induction and restored the hippocampal gene expression signature of the Tg2576 mice to wild type levels. Consistent with these findings, we also found that that genetic reduction of the ribosomal protein S6 kinase 1 (S6K1), a protein kinase directly downstream of mTOR, improved synaptic plasticity and spatial memory deficits, and reduced the accumulation of amyloid-â and tau, in 3xTg-AD mice. Mechanistically, these changes were linked to reduced translation of tau and the beta-site APP cleaving enzyme 1 (BACE-1), a key enzyme in the generation of amyloid-â.
Given the overwhelming evidence showing that reducing mTOR signaling increases lifespan and health span, the data presented here have profound clinical implications for aging and AD and provide the molecular basis for how aging may contribute to AD pathology. Our results implicate hyperactive mTOR/S6K1 signaling as a previous unidentified signaling pathway underlying gene-expression dysregulation, synaptic and cognitive deficits in Alzheimer s disease
Fault tolerant solutions for ac multidrive systems
No full textQuesta tesi, presenta uno studio riguardante sistemi in cui operano più azionamenti elettrici, i quali possono essere collegati in modo da definire un sistema multi-drive. In questo modo, una nuova topologia tollerante ai guasti è stata sviluppata e verificata sperimentalmente, in cui i drive sani supportano quelli guasti, evitando interruzioni che potrebbero essere critiche per motivi di sicurezza o economiche. La valutazione delle performance e dell efficienza durante le operazioni dopo il guasto è realizzata con sistemi multi-drive con due o tre azionamenti elettrici. Il sistema multi-drive composto da due azionamenti, di cui uno rotante e l altro statico, è usato anche per analizzare un sistema di generazione eolica.
Un ulteriore aspetto analizzato, riguarda la stima corretta della posizione di rotore di un singolo azionamento elettrico, presente in un sistema multi-drive, con sensori a bassa risoluzione. A causa di guasti che possono accadere su tali sensori, un opportuna tecnica di compensazione è presentata e verificata con tre diversi algoritmi
Studi geologici di dettaglio per la definizione di modelli bidimensionali per la valutazione della risposta sismica locale in terreni vulcanici.
No full textIl progetto di ricerca, i cui contenuti riguardano il versante orientale dell'area vulcanica del Monte Etna, consiste principalmente in studi geologici di dettaglio per la definizione di modelli bidimensionali ai fini della valutazione della Risposta Sismica Locale (RSL).
Inizialmente l attività di ricerca è stata incentrata sulla ricostruzione del modello geologico di questi territori, prestando particolare attenzione alla distinzione tra i terreni di copertura e quelli del bedrock.
La Carta geologica del versante orientale dell Etna (scala 1:25.000) rappresenta il più importante risultato ottenuto al termine di questa fase della ricerca. Durante la realizzazione della carta, oltre le unità laviche, sono stati cartografati i depositi marini e continentali che caratterizzano la successione vulcanostratigrafica. I dati raccolti, unitamente alle indagini di sottosuolo e alle datazioni disponibili in letteratura, hanno portato all individuazione di diversi orizzonti epiclastici. Tali depositi sono caratterizzati da una buona continuità laterale che ne consente l uso come livelli guida nella correlazione di successioni stratigrafiche affioranti in settori diversi del vulcano. Applicando questa metodologia, le diverse unità laviche sono state definite in base alla loro posizione rispetto agli orizzonti epiclastici di riferimento.
La Carta geologica, corredata di dettagliate sezioni geologiche, mette in evidenza la complessità della geometria del sottosuolo etneo, dominato da una notevole variabilità sia laterale che verticale delle diverse litologie, anche a brevissima distanza.
Nella seconda fase della ricerca, dopo aver individuato alcuni siti campione da utilizzare come modelli per la comprensione dei fattori che influenzano la RSL nell'area vulcanica etnea, si è proceduto all analisi numerica della risposta in superficie attraverso il codice di calcolo STRATA.
I risultati delle simulazioni consentono di affermare che l'amplificazione sismica in questi terreni, indipendentemente dalla profondità cui viene posto il bedrock, è principalmente governata dal contrasto d'impedenza dovuto agli strati di copertura più superficiali, con velocità delle onde di taglio Vs più basse. Le misure di noise confermano tale ipotesi considerato che non sono stati rilevati picchi di amplificazione a bassa frequenza attribuibili a contrasti d'impedenza profondi
Tecniche innovative di propagazione e di caratterizzazione di specie e varietà di Opuntia e generi affini
No full textLe specie appartenenti al genere Opuntia e ad alcuni generi affini riscuotono crescente interesse per la loro elevata efficienza dell uso dell acqua che deriva dal loro particolare metabolismo; il loro utilizzo è suggerito in zone aride e semiaride non solo per la produzione di frutti ma anche per l ottenimento di biomassa da destinare all alimentazione animale e come risorsa energetica. Il lavoro condotto nell ambito del Corso di dottorato di ricerca in Produttività delle piante coltivate in ambiente mediterraneo è stato incentrato su una serie di interventi individuati come preliminari rispetto alla possibile introduzione in coltura di specie e varietà di Opuntia che possano essere destinate alla produzione di biomassa. Gli interventi individuati si prefiggono l obiettivo di intervenire su alcune criticità del settore, riguardanti la mancanza di idonee varietà, la ridotta conoscenza della loro base genetica, la necessità di avviare una filiera vivaistica che possa soddisfare le esigenze di qualità del materiale di propagazione per impianti ad elevata densità. Tutti gli aspetti sopra indicati devono avvalersi di protocolli di propagazione altamente efficienti alternativi a quelli attualmente diffusi, che presentano limiti quantitativi e di carattere fitosanitario. Pertanto sono state sviluppate una serie di attività, coerenti con l obiettivo generale, e che hanno mosso dalla introduzione sul territorio nazionale di 23 genotipi tra quelli già selezionati da parte dell Instituto Agrônomico de Pernambuco (IPA) di Recife (Brasile). Il nuovo materiale vegetale, previo controllo fitosanitario ed acclimatazione, è stato posto a dimora nel campo collezione destinato alle specie di Opuntia presso l Azienda Agraria Sperimentale dell Università degli Studi di Catania. Allo scopo di poter individuare e caratterizzare tale materiale in maniera univoca, nonché di consentirne la tracciabilità in futuro, è stata effettuata una caratterizzazione genetica di tutte le accessioni attraverso l utilizzo di 8 marcatori microsatelliti. È stato possibile così individuare le relazioni tra i nuovi genotipi e le principali specie di Opuntia. Tale aspetto risulta di particolare interesse per le specifiche caratteristiche tassonomiche di queste specie per le quali esiste un elevato grado di commistione genetica ed anche di indeterminatezza del relativo inquadramento tassonomico, reso ancora più problematico dalla difficoltà di utilizzo di descrittori di tipo morfologico.
Un altro aspetto fondamentale della ricerca ha riguardato la definizione e la valutazione di una serie di protocolli di micropropagazione per specie e varietà afferenti al genere Opuntia, attraverso l utilizzo di sistemi ad immersione temporanea (TIS). A tal fine, allo scopo di individuare le migliori condizioni, soprattutto in termini di composizione del substrato, di caratteristiche microclimatiche dell ambiente di coltura, nonché di parametri di funzionamento del sistema, anche in relazione alla possibilità di una sua quanto più possibile completa automazione, sono state allestite numerose prove sperimentali che hanno permesso la definizione di idonei protocolli per una varietà individuata come modello e, successivamente, adattati ad altre varietà di interesse. Degno di interesse appare il fatto che il protocollo previsto sia stato definito sino alla fase di acclimatazione prevedendo anche delle prove utili per aumentare l efficienza produttiva nella filiera vivaistica, nonché per favorire il trasporto dei propaguli in assenza di substrato per un periodo di tempo ragionevolmente lungo.
La mole di risultati ottenuti, che spaziano dall incremento delle accessioni disponibili, alla caratterizzazione molecolare ed alla definizione di protocolli di propagazione ad elevata efficienza potranno consentire la realizzazione di impianti intensivi nei quali valutare la risposta delle varietà selezionate in termini di adattabilità e di produzione di biomassa
From diagnosis to therapy: algorithmic methodologies for precision medicine
No full textIn recent years, it has become established the idea of a novel medicine where a patient is the center around which multidisciplinary teams (made up of physicians, statisticians and bioinformaticians) sew targeted treatments. Precision medicine involves the use of detailed patient-specific molecular information for diagnosing, categorizing and guiding treatment of a disease, with the main purpose of improving the clinical outcome compared to a more classical approach. In precision medicine it is supposed that the cause of a disease is at least partially attributable to specific genetic or epigenetic characteristics of a patient. Therefore, identifying these specificities helps building the best treatment for each individual. Next-generation sequencing techniques are massively employed, giving the ability to quickly and at relatively low cost analyze whole genomes, epigenomes and transcriptomes. This ability is clinically important since the prediction of treatment effectiveness is usually affected by many factors.
A fundamental function in this new medicine is played by bioinformatics. It has a crucial role in every aspect of precision medicine, such as the accurate classification of patients, the prediction of new therapies based on current knowledge, the identification of possible outcomes of a disease or therapy, and the enrichment of current knowledge on pathogenic processes or on pharmaceuticals.
The aim of this thesis is the development of an integrated framework, based on synergistically operating tools, models and algorithms, which help to fill some of the major gaps in each step of the production of highly customized therapies, overcoming, if possible, the limitations of currently employed techniques, defining a new standard for precision medicine informatics
Analysis of high resolution observations of sunspots fine structures
No full textThis Ph.D. thesis deals with the study of the interaction between plasma and magnetic fields on the Sun. Observations acquired during two observing campaigns, one at the Solar Swedish Tower and the other at the Richard B. Dunn Solar Telescope, provided high-resolution data which were used to study the details of some phenomena occurring in the Sun.
In particular, this work aims to extend and consolidate our knowledge on the formation and evolution of sunspots observed in the solar photosphere. The first aspect which was investigated concerns the study of the mechanism of the penumbra formation in a sunspot. In this regard, I give my contribution in explaining the behaviour of the magnetic field forming the penumbral filaments. A second aspect concerns the study of the kinematic and magnetic properties of a light bridge separating
into two parts the umbra of a sunspot. I found that there is a relationship between the upflow motions in the light bridge dark lane and the magnetic field configuration. The third aspect concerns the study of the
properties of granules in a light bridge and in the quiet Sun using a new algorithm developed in collaboration with the Department of Mathematics of the University of Catania. In particular, I compared the size, mean continuum intensity and Doppler velocity between the granules forming the light bridge and those of the quiet Sun. In the conclusion, I give my interpretation of the observed phenomena and suggest future observations to confirm these results and support theoretical models
Risk taking in sport
No full textThe present study examined the personological characteristics that define two groups of experienced sportspeople, skydivers and cavers, with the aim to identify the personality factors that may be good predictors of risk.
Moreover, the present study examined whether and how the skydiving and caving, high-risk sports, can affect their control of emotions, anxiety and mood.
To carry out the study, 23 skydivers and 34 cavers were asked to complete four questionnaires: Big Five Questionnaire-2, Profile of Mood States, State-Trait Anxiety Inventory Forma-Y and Risk Taking Inventory.
The results confirmed the role of conscientiousness and energy, as significant predictors for risk-taking in the skydivers.
Data analysis also found that social desirability is negatively correlated with both state anxiety the total index of mood disorders, and is positively correlated with emotional control.
In the group of cavers the significant role of conscientiousness is represented mainly by scrupulosity, in line with the characteristics of their activity.
In addition, emerges the factor cooperativity: inside the caves is essential collaboration between the members of the group.
Another aspect that appears to play a significant role is the Opening of Culture, which describes the tendency of the subjects to increase their knowledge, and that seems to be a predominant feature in the cavers.
The Structural Equation Model (SEM) showed in both groups a significant correlation between the Big Five Questionnaire-2 (BFQ-2) and Precautionary behavior (PB), most significant in the group of skydivers, while the BFQ-2 did not affect DRT factor, i.e. the risk-taking propensity of subjects.
In addition, SEM indicated in both samples the lack of a significant correlation between POMS (Profile of Mood States), and PB as well as DRT, the propensity to take risks. The model has also indicated that there is a small but significant relationship between BFQ-2 and POMS.
In addition, the statistical comparison between the two groups have shown that, although both are defined high-risk sports, these are significant differences in some variables that may be predictors of the choice of a sport rather than the other.
Future research should extend the study to other sports that involve a risk-taking in order to understand the reasons behind the decision to practice these sports and how people learn strategies of self-regulation in this domain