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Analysis of far-infrared (FIR) high spectral resolution data for cloud studies
Get PDFThe Far-Infrared Outgoing Radiation Understanding and Monitoring (FORUM) mission has recently been selected by the European Satellite Agency (ESA) as 9 th Earth Explorer mission. FORUM mission aims at studying the water vapor and clouds by filling the long-standing gap in Far-Infrared (FIR) spectral observations from space. In the framework of the FORUM mission, this thesis analyses FIR measurements to characterize the spectral signatures of radiance in presence of ice clouds. At this purpose, a cloud identification and classification code (named CIC) is implemented. CIC is an innovative machine learning algorithm, based on principal component analysis, able to perform cloud detection and scene multi-class classification. CIC is easily adaptable to different datasets and type of spectral sensors. It is firstly tested against a synthetic dataset comprising simulated measurements of the FORUM mission. Subsequently, CIC is applied to airborne interferometric data and finally it is used for the analysis of measured downwelling radiances collected in very dry conditions on the Antarctic Plateau. Provided the excellent performances of the algorithm, especially in the identification of thin cirrus clouds, CIC is adopted as the classificator in the official ESA FORUM End-to-End simulator (FE2ES). The FE2ES is a complex chain of codes used to simulate the entire FORUM mission from satellite orbit and geometry to level 2 product analysis. An extensive use of CIC is performed on ground-based radiances collected in Antarctica. The dataset is exploited to test and to optimize the CIC algorithm and for the developing of punctual statistic of cloud occurrence in the Antarctic Plateau. Meteorological conditions from this region are also analysed and correlated with the presence of clouds. The studies presented in this work showed the potentiality and the importance of the exploitation of spectral radiance measurements in the FIR for cloud identification and classification
Indocyanine green fluorescence angiography during radical and conservative surgery for recto-sigmoid endometriosis: a feasibility study
Get PDFObiettivo: Valutare la fattibilità e la sicurezza dell’angiografia a fluorescenza mediante l’utilizzo endovenoso di verde di indocianina (near-infrared indocyanine green, NIR-ICG) per la valutazione della vascolarizzazione dell'area di intestino sottoposta ad escissione chirurgica per endometriosi retto-sigmoidea (rectosigmoid endometriosis, RSE).
Materiali e metodi: Studio prospettico, monocentrico, preliminare su pazienti consecutive candidate a escissione chirurgica mini-invasiva di RSE da Maggio 2018 a Gennaio 2020 presso l’Ospedale Universitario Sant’Orsola di Bologna. Mediante valutazione NIR-ICG è stato valutato il grado di fluorescenza dell'area di intestino operata tramite una scala Likert 0-2, come segue: 0 o "assente" (nessuna fluorescenza osservata), 1 o "irregolare" (distribuzione non uniforme o fluorescenza debole) e 2 o "regolare" (fluorescenza uniforme e simile al colon prossimale). L'outcome primario di questo studio è stato il tasso di completamento del protocollo della valutazione NIR-ICG. Gli outcome secondari comprendevano il tempo del protocollo, la concordanza inter-operatore, le complicanze peri-operatorie ed eventuali modifiche della strategia chirurgica adottata.
Risultati: Durante il periodo di studio, 46 pazienti che soddisfacevano i criteri di eleggibilità sono state arruolate nello studio. In tutti i casi il protocollo NIR-ICG è stato eseguito con successo. Quarantacinque (97.8%) casi hanno presentato una fluorescenza regolare (scala Likert 2); in un solo caso (2.2%), l’imaging NIR-ICG ha mostrato una fluorescenza irregolare (scala Likert 1) dopo resezione discoide ed il chirurgo ha posizionato a scopo preventivo alcuni punti di sutura di rinforzo dell’anastomosi. Non sono state registrate complicanze legate all'uso dell’ICG. Il tempo mediano del protocollo è stato di 4 (range, 3-5) minuti. È stato osservato un eccellente accordo inter-operatore.
Conclusione: L'imaging NIR-ICG per la valutazione della perfusione intestinale dopo intervento chirurgico per RSE sembra essere un metodo fattibile, sicuro e riproducibile. Sono necessari ulteriori studi prospettici per valutare l'efficacia dell’angiografia a fluorescenza con NIR-ICG nel ridurre la morbilità associata alla chirurgia colo-rettale per RSE.Objective: To evaluate feasibility and safety of near-infrared indocyanine green (NIR-ICG) imaging for bowel vascularization assessment after minimally invasive conservative and radical excision of recto-sigmoid endometriosis (RSE).
Materials and methods: Prospective, monocentric, preliminary study on consecutive symptomatic patients scheduled for minimally invasive surgical excision of RSE from May 2018 to January 2020 at the Sant’Orsola University Hospital in Bologna. Fluorescence degree of the bowel resected area was evaluated through NIR-ICG evaluation using a three-point Likert scale, as follows: 0 or "absent" (no fluorescence observed), 1 or "irregular" (non-uniform or weak fluorescence) and 2 or "regular" (uniform distribution of fluorescence and similar to the proximal colon). The primary outcome of this study was the protocol completion rate. Secondary outcomes included protocol time, inter-operator agreement, peri-operative complications and any changes in the surgical strategy adopted.
Results: During the study period, 46 patients who met the eligibility criteria were enrolled in the study. In all cases NIR-ICG protocol was successfully performed. Forty-five (97.8%) cases showed regular fluorescence (Likert 2 scale); in one patient (2.2%) with irregular fluorescence after discoid excision, we changed the surgical strategy reinforcing anastomotic suture. No complications related to the use of ICG were recorded. Median protocol time was 4 (range, 3-5) minutes. Excellent inter-operator agreement was observed.
Conclusion: NIR-ICG imaging for bowel perfusion evaluation after RSE surgery appears to be a feasible, safe and reproducible method. Further prospective studies are needed to evaluate its efficacy in reducing morbidity associated with colorectal surgery for RSE
School design between preservation and innovation: elements of continuity and discontinuity. An empirical research on teachers' attitudes and declarations among the Comprehensive Schools in the province of Udine and in the Italian State schools in Spain.
Get PDFLa presente ricerca è rivolta allo studio della progettazione scolastica ed è stata finalizzata all’osservazione dell’impatto prodotto su di essa dalla progressiva introduzione dei nuovi documenti di progettazione oggi in uso nelle scuole italiane. Al fine di delineare i costrutti fondamentali da indagare è stato realizzato uno studio preliminare della letteratura scientifica di riferimento a partire dal dibattito statunitense sul curricolo avviato a inizio Novecento. Dopo una ricognizione sui successivi studi realizzati in ambito nordamericano ed europeo, una parte della ricerca è stata specificamente dedicata al dibattito nel contesto italiano. L’ultima parte di questo percorso è stata rivolta alla recente ripresa di interesse verso le ricerche sul curricolo e le nuove prospettive portate dall’internazionalizzazione di questi studi dovute all’opera dei cosiddetti riconcettualizzatori.
La seconda parte della ricerca è stata dedicata allo studio della normativa scolastica italiana in tema di progettazione a partire dal secondo dopoguerra. Particolare attenzione è stata data alle riforme degli ultimi due decenni.
Su queste basi teoriche e concettuali è stato quindi predisposto il percorso di ricerca empirica realizzato nelle scuole campione e la successiva analisi dei dati raccolti. Lo scopo della ricerca è stato quello di evidenziare e quantificare l’entità e la natura dei potenziali elementi di continuità e di discontinuità presenti nel sistema di progettazione scolastica attraverso la voce dei docenti che operano sul campo. Il campione è stato individuato tra gli istituti comprensivi della provincia di Udine.
Una ricerca analoga è stata condotta presso le scuole statali italiane in Spagna, nelle città di Madrid e Barcellona, dove ancora non sono state introdotte le nuove pratiche di progettazione. Questo ha consentito di poter comparare i dati in un contesto paragonabile a quello previgente in Italia e di fare ulteriori valutazioni sull’impatto prodotto sul lavoro dei docenti dall’introduzione dei nuovi documenti di progettazione.This research is addressed to the study of school planning and aimed to the observation of the impact produced on it by the progressive introduction of new planning documents nowadays used in the Italian public school system. In order to trace the main constructs to be investigated a preliminary study on the related scientific literature has been held starting from the north American debate about the curriculum initiated at the beginning of the XX Century. The last part of this exploration has been dedicated to the recent resumption of interest toward curriculum studies due to the new perspectives brought by their internationalization and the works of the so called reconceptualists.
The second part of the research regards the evolution of the Italian school planning norms starting from the second post-war period. Particular attention has been given to the Italian reform laws of the last two decades.
According to this theoretical and conceptual basis, the empirical research put in place has been realized among the comprehensive schoolteachers operating in the province of Udine and followed by the analysis of the data collected.
The aim of the research has been to highlight and quantify entity and nature of the potential continuity and discontinuity elements present in the school planning system through the voice of the teachers working on the ground.
A similar research has been held at the Italian state schools in Spain, in the towns of Madrid and Barcelona, where the new planning practices have not been introduced yet. This allowed a comparison with data collected in a context partly similar to the one pre-existing in Italy, so to make further assessments on the impact produced on the teachers’ work by the introduction of the new planning documents
Development of 3D Cancer Cell Models to Test Metabolic Interventions as an Anticancer Strategy
Get PDFIn recent years, it has become evident that the role of mitochondria in the metabolic rewiring is essential for cancer development and progression. The metabolic profile during tumorigenesis has been performed mainly in traditional 2D cell models, including cell lines of various lineages and phenotypes. Although useful in many ways, their relevance can be often debatable, as they lack the interactions between different cells of the tumour microenvironment and/or interaction with the extracellular matrix 1,2. Improved models are now being developed using 3D cell culture technology, contributing with increased physiological relevance 3,4.
In this work, we improved a method for the generation of 3D models from healthy and tumour colon tissue, based on organoid technology, and performed their molecular and biochemical characterization and validation. Further, in-plate cryopreservation was applied to these models, and optimal results were obtained in terms of cell viability and functionality of the cryopreserved models. We also cryopreserved colon fibroblasts with the aim to introduce them in a co-culture cryopreserved model with organoids. This technology allows the conversion of cell models into “plug and play” formats. Therefore, cryopreservation in-plate facilitates the accessibility of specialized cell models to cell-based research and application, in cases where otherwise such specialized models would be out of reach. Finally, we briefly explored the field of bioprinting, by testing a new matrix to support the growth of colon tumour organoids, which revealed promising preliminary results.
To facilitate the reader, we organized this thesis into chapters, divided by the main points of work which include development, characterization and validation of the model, commercial output, and associated applications. Each chapter has a brief introduction, followed by results and discussion and a final conclusion. The thesis has also a general discussion and conclusion section in the end, which covers the main results obtained during this work
Augmenting the Knowledge Pyramid with Unconventional Data and Advanced Analytics
Get PDFThe volume, variety, and high availability of data backing decision support systems have impacted on business intelligence, the discipline providing strategies to transform raw data into decision-making insights. Such transformation is usually abstracted in the "knowledge pyramid", where data collected from the real world are processed into meaningful patterns. In this context, volume, variety, and data availability have opened for challenges in augmenting the knowledge pyramid. On the one hand, the volume and variety of unconventional data (i.e., unstructured non-relational data generated by heterogeneous sources such as sensor networks) demand novel and type-specific data management, integration, and analysis techniques. On the other hand, the high availability of unconventional data is increasingly attracting data scientists with high competence in the business domain but low competence in computer science and data engineering; enabling effective participation requires the investigation of new paradigms to drive and ease knowledge extraction. The goal of this thesis is to augment the knowledge pyramid from two points of view, namely, by including unconventional data and by providing advanced analytics. As to unconventional data, we focus on mobility data and on the privacy issues related to them by providing (de-)anonymization models. As to analytics, we introduce a higher abstraction level than writing formal queries. Specifically, we design advanced techniques that allow data scientists to explore data either by expressing intentions or by interacting with smart assistants in hand-free scenarios
Augmented Reality Interfaces for Efficient and Safe Applications in Industry and Services
Get PDFLo scopo della ricerca ha riguardato la concezione, l'implementazione ed il test di nuovi concetti di interfaccia basati sulla Realta' Aumentata (AR) per applicazioni nei campi dell'industria e dei servizi, tenendo conto della rapida evoluzione dei sistemi e dei dispositivi inerenti a tale tecnologia in continuo sviluppo.
Il risultato finale dello studio e' principalmente rappresentato da un “Video-Based Adaptive and Collaborative AR System”, in cui (a) la tecnologia AR ottica (see-through) è abilitata alla ricezione di stream video multipli in tempo reale da differenti videocamere e/o display (“Video-Based”), (b) gli utenti condividono lo stesso ambiente ma sperimentano differenti visualizzazioni AR ("Adaptive"), (c) lo scambio di informazioni avviene fra tutte le componenti e fra tutti i livelli – fra gli operatori, nonché fra gli stessi ed i loro supervisori, quest’ultimi aventi il compito di ottimizzare le strategie di teamwork in tempo reale ("Collaborative").
Tale Sistema AR ha valore generale e può essere esteso a numerosi campi di applicazione del mondo dell’industria e dei servizi.
Come casi di studio particolari, sono stati considerati i contesti "safety-critical" delle torri di controllo aeroportuali e degli elicotteri. In questo modo, la trattazione ha riguardato rispettivamente sia gli impianti di gestione/controllo che i mezzi di trasporto, oovero le due macro-aree in cui ricadono non solo tutte le applicazioni AR relative al campo aeronautico, bensì all’intero settore dei trasporti (terrestri, marittimi, aerei), sia di carattere civile che militare.
Integrando stream video multipli in tempo reale all’interno dei layers virtuali della tecnologia AR ottica (see-through), la caratteristica “Video-Based” del Sistema AR implementato offre la possibilita' di colmare il gap di ricerca rappresentato dall’assenza di soluzioni ibride derivanti dalla fusione delle differenti funzionalità che caratterizzano entrambe le categorie distinte (rispettivamente tecnologia AR ottica e video) in cui vengono suddivisi tutti i dispositivi AR.The overall aim of the research was to conceive, develop and test new interface concepts based on Augmented Reality (AR) for applications in industry and services, taking into account the fast evolution of systems and devices dedicated to this quickly maturing technology.
The final result of the PhD study is mainly represented by a “Video-Based Adaptive and Collaborative AR System”, where optical AR technology is enabled to receive multiple live video streams from different cameras and/or displays (“Video-Based”), users share the same environment but experience different AR visualizations (Adaptive) and where information exchange happens among all components and all levels (Collaborative) - among users and between users and team supervisors, with the latter having the role of optimizing team strategies in real-time.
This AR System has a flexible character and can be generalized and easily extended to many application fields in industry and services.
The case studies here considered, namely related to the airport control towers and helicopters, have been developed in order to support in understanding the impact that the implementation of this kind of AR concept would bring to such safety-critical operations in the aeronautical sector.
The “Video-Based” feature offers the possibility of integrating multiple live video streams in the virtual layer of an optical AR system and tackles the research gap represented by the lack of hybrid solutions deriving from the fusion of the different functionalities characterizing both the distinctive categories the whole AR technology is divided into, namely optical and video AR technology
On the topological theory of Group Equivariant Non-Expansive Operators
Get PDFIn this thesis we aim to provide a general topological and geometrical framework for group equivariance in the machine learning context. A crucial part of this framework is a synergy between persistent homology and the theory of group actions. In our approach, instead of focusing on data, we focus on suitable operators defined on the functions that represent the data. In particular, we define group equivariant non-expansive operators (GENEOs), which are maps between function spaces endowed with the actions of groups of transformations. We investigate the topological, geometric and metric properties of the space of GENEOs. We begin by defining suitable pseudo-metrics for the function spaces, the equivariance groups, and the set of GENEOs and proving some results about our model. Basing on these pseudo-metrics, we prove that the space of GENEOs is compact and convex, under the assumption that the function spaces are compact and convex. These results provide fundamental guarantees in a machine learning perspective. We show some new methods to build different classes of GENEOs in order to populate and approximate the space of GENEOs. Moreover, we define a suitable Riemannian structure on manifolds of GENEOs making available the use of gradient descent methods
1H NMR Relaxation Characterization Of Hydrates
Get PDFTo distinguish the components of NMR signals from hydrated materials and to monitor their evolution after the addition of water to the powders, during the first two days of hydration.
To implement the 3 Tau Model in a MATLAB script, called 3TM, provided with a Graphical User Interface (GUI), to easily use the 3 Tau Model with NMRD profiles.
The 3 Tau Model, developed a few years ago is used for interpreting the dispersion (NMRD profiles, dependence on the Larmor frequency) of the longitudinal relaxation times, for liquids confined in porous media. This model describes the molecular dynamics of confined molecules by introducing three characteristic correlation times and additional outputs
Dissection of the protective response elicited by the DOMV component of the 4CMenB vaccine
Get PDFNeisseria meningitidis serogroup B is the major etiological agent of meningitis and life-threatening sepsis, against which two vaccines are licensed. The 4CMenB vaccine is composed of three major protein antigens (fHbp, NHBA and NadA) and detergent-extracted outer membrane vesicles (DOMV) from the NZ98/254 strain. DOMV are safe, immunogenic and able to raise bactericidal antibodies, mainly attributed to the immunodominant PorA protein. Nevertheless, DOMV offer a complex reservoir of potentially immunogenic proteins, whose relative contribution in protection is still poorly characterized.
By testing antisera from vaccinated infants in serum bactericidal assay, we observed that the addition of DOMV in the vaccine formulation enhanced breadth of coverage compared to recombinant proteins alone against a panel of 11 meningococcal strains mismatched for the vaccine antigens. To unravel the DOMV components involved in such protection, 30 DOMV antigens were cloned and expressed in Escherichia coli as recombinant proteins and/or in vesicles to maintain their native conformation. Samples obtained were both included in tailor-made protein-microarrays to immunoprofile the antibody repertoire raised by DOMV-containing formulations and were individually used for mouse immunization studies to assess their ability to induce bactericidal antibodies.
The protein-array immunosignature of mouse DOMV/4CMenB antisera unveiled a subset of 8 DOMV-reactive proteins potentially responsible for the additional protective responses. The antisera derived from mouse immunizations showed high levels of antibodies and recognized the corresponding antigen across different meningococcal strains. Among the protein-array reactive antigens, OpcA, NspA and PorB induced antibodies able to kill 10 of the 11 genetically diverse meningococcal strains and the specificity of the protective role of OpcA and PorB was also confirmed in 4CMenB infant vaccinee sera.
In conclusion, we identified additional PorA-independent antigens within DOMV involved in broadening the coverage of 4CMenB, thus supporting the key role played by vesicles in this multivalent formulation
The legacy of Mario Vargas Llosa in the Contemporary Spanish-American Literature
Get PDFLo que sigue es el intento de trazar el contexto literario en el que ha ido desarrollándose la narrativa contemporánea y las posturas de los autores nacidos en las decadas de los sesenta y los setenta frente a la tradición de la “nueva novela hispanoamericana”, así llamada por Carlos Fuentes, para poner un mayor enfoque en la actitud asumida por las nuevas generaciones con respecto a Mario Vargas Llosa, cuya influencia aún sigue vigente a pesar de su notoria pertenencia al fenómeno del boom.
Puesto que el ámbito de esta investigación no puede prescindir de una aproximación a las tensiones intergeneracionales que han definido la literatura hispanoamericana a lo largo de los últimos sesenta años, en el primer capítulo se intentará trazar un mapa general de largo alcance que pueda servir de telón de fondo para enfocar el legado del boom. Luego, se abarcará el eje de la herencia narrativa de Mario Vargas Llosa, deteniéndose principalmente en la recepción del escritor arequipeño tanto en el ámbito continental como en el caso específico de Perú donde tiene una vigencia casi forzosa.
Finalmente, se llevará a cabo el proceso comparativo: el abanico de novelistas que serán tratados en la segunda parte de la tesis está compuesto por Jorge Eduardo Benavides (1964), Alberto Fuguet (1964), Edmundo Paz Soldán (1967), Juan Gabriel Vásquez (1973) y Claudia Salazar Jiménez (1976).The legacy of Mario Vargas Llosa in the Contemporary Spanish-American Literature could be a singularity in the specific context of the Boom and the legacy which it left. This investigation analyse the reaction of some spanish-american authors about the Boom's influence on the younger generations of latin-american lectors, writers and critics. The thesis includes a comparative study between Mario Vargas Llosa's novels and literary theories, and the works of Jorge Eduardo Benavides, Alberto Fuguet, Edmundo Paz Soldán, Juan Gabriel Vásquez y Claudia Salazar Jiménez