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Functional engineering of hybrid heterostructures for application in electronic, optical and optoelectronic nanostructured devices
Get PDFInterfacing materials with different intrinsic chemical-physical characteristics allows for the generation of a new system with multifunctional features. Here, this original concept is implemented for tailoring the functional properties of bi-dimensional black phosphorus (2D bP or phosphorene) and organic light-emitting transistors (OLETs).
Phosphorene is highly reactive under atmospheric conditions and its small-area/lab-scale deposition techniques have hampered the introduction of this material in real-world applications so far. The protection of 2D bP against the oxygen by means of functionalization with alkane molecules and pyrene derivatives, showed long-term stability with respect to the bare 2D bP by avoiding remarkable oxidation up to 6 months, paving the way towards ultra-sensitive oxygen chemo-sensors. A new approach of deposition-precipitation heterogeneous reaction was developed to decorate 2D bP with Au nanoparticles (NP)s, obtaining a “stabilizer-free” that may broaden the possible applications of the 2D bP/Au NPs interface in catalysis and biodiagnostics. Finally, 2D bP was deposited by electrospray technique, obtaining oxidized-phosphorous flakes as wide as hundreds of µm2 and providing for the first time a phosphorous-based bidimensional system responsive to electromechanical stimuli.
The second part of the thesis focuses on the study of organic heterostructures in ambipolar OLET devices, intriguing optoelectronic devices that couple the micro-scaled light-emission with electrical switching. Initially, an ambipolar single-layer OLET based on a multifunctional organic semiconductor, is presented. The bias-depending light-emission shifted within the transistor channel, as expected in well-balanced ambipolar OLETs. However, the emitted optical power of the single layer-based device was unsatisfactory. To improve optoelectronic performance of the device, a multilayer organic architecture based on hole-transporting semiconductor, emissive donor-acceptor blend and electron-transporting semiconductor was optimized. We showed that the introduction of a suitable electron-injecting layer at the interface between the electron-transporting and light-emission layers may enable a ≈ 2× improvement of efficiency at reduced applied bias
1° level of automation: the effectiveness of adaptive cruise control on driving and visual behaviour
Get PDFThe research activities have allowed the analysis of the driver assistance systems, called Advanced Driver Assistance Systems (ADAS) in relation to road safety. The study is structured according to several evaluation steps, related to definite on-site tests that have been carried out with different samples of users, according to their driving experience with the ACC. The evaluation steps concern:
•The testing mode and the choice of suitable instrumentation to detect the driver’s behaviour in relation to the ACC.
•The analysis modes and outputs to be obtained, i.e.:
- Distribution of attention and inattention;
- Mental workload;
- The Perception-Reaction Time (PRT), the Time To Collision (TTC) and the Time Headway (TH).
The main purpose is to assess the interaction between vehicle drivers and ADAS, highlighting the inattention and variation of the workloads they induce regarding the driving task. The research project considered the use of a system for monitoring visual behavior (ASL Mobile Eye-XG - ME), a powerful GPS that allowed to record the kinematic data of the vehicle (Racelogic Video V-BOX) and a tool for reading brain activity (Electroencephalographic System - EEG). Just during the analytical phase, a second and important research objective was born: the creation of a graphical interface that would allow exceeding the frame count limit, making faster and more effective the labeling of the driver’s points of view.
The results show a complete and exhaustive picture of the vehicle-driver interaction. It has been possible to highlight the main sources of criticalities related to the user and the vehicle, in order to concretely reduce the accident rate. In addition, the use of mathematical-computational methodologies for the analysis of experimental data has allowed the optimization and verification of analytical processes with neural networks that have made an effective comparison between the manual and automatic methodology
Synthesis, characterization and potential applications of novel metal-organic frameworks
Get PDFThe research work described in this thesis concerns the synthesis, characterization, and applications of two kinds of metal-organic frameworks (MOFs), Copper based MOF (Cu-MOF) and zirconium based MOF (Zr-MOF) functionalized with new linkers. The common thread of this research project can be summarized in three work phases: first, the synthesis and characterization of new organic linkers is described, followed by the presentation of the different optimization conditions for the MOFs synthesis.
Second, the new materials were fully characterized using several complementary techniques, such as infrared (ATR-FTIR) and Raman spectroscopy, X-ray powder diffraction spectroscopy (PXRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), atomic absorption spectroscopy (AAS) as well as thermal and surface area measurements.
Final, to obtain a complete work the possible environmental applications of the new materials were explored
Molecular changes induced by a centrally-induced state of synthetic torpor in multiple organs:a new strategy for radioprotection.
No full textTorpor is a successful survival strategy displayed by several mammalian species to cope with harsh environmental conditions. A complex interplay of ambient, genetic and circadian stimuli acts centrally to induce a severe suppression of metabolic rate, usually followed by an apparently undefended reduction of body temperature. Some animals, such as marmots, are able to maintain this physiological state for months (hibernation), during which torpor bouts are periodically interrupted by short interbouts of normothermia (arousals). Interestingly, torpor adaptations have been shown to be associated with a large resistance towards stressors, such as radiation: indeed, if irradiated during torpor, hibernators can tolerate higher doses of radiation, showing an increased survival rate. New insights for radiotherapy and long-term space exploration could arise from the induction of torpor in non-hibernators, like humans.
The present research project is centered on synthetic torpor (ST), a hypometabolic/hypothermic condition induced in a non-hibernator, the rat, through the pharmacological inhibition of the Raphe Pallidus, a key brainstem area controlling thermogenic effectors. By exploiting this procedure, this thesis aimed at: i) providing a multiorgan description of the functional cellular adaptations to ST; ii) exploring the possibility, and the underpinning molecular mechanisms, of enhanced radioresistance induced by ST. To achieve these aims, transcriptional and histological analysis have been performed in multiple organs of synthetic torpid rats and normothermic rats, either exposed or not exposed to 3 Gy total body of X-rays.
The results showed that: i) similarly to natural torpor, ST induction leads to the activation of survival and stress resistance responses, which allow the organs to successfully adapt to the new homeostasis; ii) ST provides tissue protection against radiation damage, probably mainly through the cellular adaptations constitutively induced by ST, even though the triggering of specific responses when the animal is irradiated during hypothermia might play a role
Preventing worker’s musculoskeletal disorders with wearable inertial sensors: ergonomics and modelling of physical human-robot interactions
Get PDFThe most widespread work-related diseases are musculoskeletal disorders (MSD) caused by awkward postures and excessive effort to upper limb muscles during work operations. The use of wearable IMU sensors could monitor the workers constantly to prevent hazardous actions, thus diminishing work injuries. In this thesis, procedures are developed and tested for ergonomic analyses in a working environment, based on a commercial motion capture system (MoCap) made of 17 Inertial Measurement Units (IMUs). An IMU is usually made of a tri-axial gyroscope, a tri-axial accelerometer, and a tri-axial magnetometer that, through sensor fusion algorithms, estimates its attitude. Effective strategies for preventing MSD rely on various aspects: firstly, the accuracy of the IMU, depending on the chosen sensor and its calibration; secondly, the correct identification of the pose of each sensor on the worker’s body; thirdly, the chosen multibody model, which must consider both the accuracy and the computational burden, to provide results in real-time; finally, the model scaling law, which defines the possibility of a fast and accurate personalization of the multibody model geometry. Moreover, the MSD can be diminished using collaborative robots (cobots) as assisted devices for complex or heavy operations to relieve the worker's effort during repetitive tasks. All these aspects are considered to test and show the efficiency and usability of inertial MoCap systems for assessing ergonomics evaluation in real-time and implementing safety control strategies in collaborative robotics. Validation is performed with several experimental tests, both to test the proposed procedures and to compare the results of real-time multibody models developed in this thesis with the results from commercial software. As an additional result, the positive effects of using cobots as assisted devices for reducing human effort in repetitive industrial tasks are also shown, to demonstrate the potential of wearable electronics in on-field ergonomics analyses for industrial applications
Analytical pyrolysis to study microplastics and other polymers in the environment
Get PDFSynthetic polymers constitute a wide class of materials which has enhanced the quality of human life, providing comforts and innovations. Anyway, the increasing production and the incorrect waste management, are leading to the occurrence of polymers in the environment, generating concern. To understand the extent of this issue, analytical investigation holds an essential position. Standardised methods have not established yet, and additional studies are required to improve the present knowledge. The main aim of this thesis was to provide comprehensive information about the potential of pyrolysis coupled with gas-chromatography and mass spectrometry (Py-GC-MS) for polymers investigation, from their characterisation to their identification and quantification in complex matrices. Water-soluble (poly(dimethylsiloxanes), PDMS bearing poly(ethylene glycol), PEG, side chains) and water-insoluble polymers (microplastics, MPs, and bioplastics) were studied. The different studies revealed the possibility to identify heterogeneous classes of polymers, fingerprinting the presence of PDMS copolymers and distinguishing chemically different polyurethanes (PURs). The occurrence of secondary reactions in pyrolysis of polymer mixtures was observed as possible drawback. Pyrolysis products indicative of secondary reactions and their reaction mechanisms were identified. Py-GC-MS also revealed its fundamental role for the identification of polymers composing commercial bioplastics items based. The results aided to identify chemicals that have the potential to migrate in sea waters. Investigations of environmental samples demonstrated the capability of Py-GC-MS to provide reliable, reproducible and comparable results about polymers in complex matrices (PEG-PDMS in sewage sludges and PURs and other MPs in road dusts and spider webs). Criticisms were especially found in quantitation, such as the retrieval reference materials, the construction of reliable calibration protocols and the occurrence of bias due to interferences between pyrolysis products. This thesis pursues the greater purpose to develop harmonised and standardised methods for environmental investigations of polymers, that is fundamental to assess the real state of the environment
Orchestration of multiscale model for computational oncology
Get PDFCancer is a challenging disease that involves multiple types of biological interactions in
different time and space scales. Often computational modelling has been facing problems that, in the
current technology level, is impracticable to represent in a single space-time continuum. To handle
this sort of problems, complex orchestrations of multiscale models is frequently done. PRIMAGE is
a large EU project that aims to support personalized childhood cancer diagnosis and prognosis. The
goal is to do so predicting the growth of the solid tumour using multiscale in-silico technologies. The
project proposes an open cloud-based platform to support decision making in the clinical management
of paediatric cancers. The orchestration of predictive models is in general complex and would require
a software framework that support and facilitate such task. The present work, proposes the
development of an updated framework, referred herein as the VPH-HFv3, as a part of the PRIMAGE
project. This framework, a complete re-writing with respect to the previous versions, aims to
orchestrate several models, which are in concurrent development, using an architecture as simple as
possible, easy to maintain and with high reusability. This sort of problem generally requires
unfeasible execution times. To overcome this problem was developed a strategy of particularisation,
which maps the upper-scale model results into a smaller number and homogenisation which does the
inverse way and analysed the accuracy of this approach
As aporias do retorno: A transmissão inter-geracional da memória traumática no sul global de língua portuguesa
Get PDFQuesta tesi propone un indagine sulla memoria del retorno a partire da una prospettiva critica che assume il “sud globale di lingua portoghese” come spazio storico e concettuale di riferimento. Si riflette sull'idea di specificità attribuita alla colonizzazione promossa dal Portogallo in Africa tenendo conto delle contraddizioni associate al movimento migratorio innescato dal processo violento di decolonizzazione dell’Africa portoghese.
Le memorie trauamatiche sul retorno espongono la violenza come componente costitutiva della realtà coloniale ma ripropongono anche dinamiche che permettono l’occultamento del razzismo. L'esplorazione della “soffitta”, assunta come metafora della memoria familiare custodita nello spazio domestico, accompagna quella dell’archivio pubblico. L’analisi dell’archivio ufficiale e della memoria familiare riflette il tentativo di stabilire un dialogo tra storia e memoria superando la logica di antitesi che tradizionalmente le contrappone.
Utilizzando il concetto criticamente problematico di “postmemoria” si riflette sulla riconfigurazione del rapporto con il passato in funzione di un’idea di “eredità come compito” assunto nel presente). La possibilità di “salvare” il passato dalla progressiva scomparsa dei testimoni comporta un pericolo di abuso ideologico connaturato al processo di trasmissione. La traduzione delle memorie coloniali sul retorno dallo spazio intimo allo spazio del dibattito pubblico mostra la relazione tra la costruzione della mitologia familiare e l’adozione del discorso lusotropicale. Il tentativo di definire la natura indecifrabile del retornado comporta la possibilità di sanzionare la violenza coloniale negando una responsabilità collettiva riferita al colonialismo. Si presenta il tentativo di configurare i termini di una questione post-coloniale portoghese dai contorni opachi. Questa tesi approda ad una conclusione aperta, articolata sul rischio sempre presente di appropriazione delle categorie critiche post-coloniali da parte dell’ideologia egemonica. Attraverso le (post)memorie (post)coloniali la denuncia del razzismo in quanto eredità permanente e la riconfigurazione dell’archivio coloniale costituiscono operazioni possibili, necessarie, ma non per questo scontate o prive di rischi.This thesis investigates on the memory of the "retorno" starting from a critical perspective that assumes the "Portuguese-speaking global south" as a historical and conceptual reference space. It provides a reflection on the idea of specificity attributed to the colonisation promoted by Portugal in Africa, taking into account the contradictions associated with the migratory movement triggered by the violent process of decolonization of Portuguese Africa. The traumatic memories on the return expose violence as a constitutive component of the colonial reality but they also reproduce the dynamics that conceal racism. The exploration of the "soffitta", taken as a metaphor for the family memory, accompanies that of the public archive. It reflects the attempt to establish a dialogue between history and memory by overcoming the logic of antithesis that traditionally opposes them. Using the critically problematic concept of "postmemory" the work reflects on the reconfiguration of the relationship between the present and the past following the idea of "legacy as a task". Saving the past from the progressive disappearance of witnesses involves a risk of ideological abuse inherent in the process of transmission. The translation of colonial memories on the return from intimate space to the space of public debate shows the relationship between the construction of family mythology and the adoption of the lusotropical discourse. Also, the attempt to define the indecipherable nature of the retornado carries the risk of sanctioning colonial violence by denying a collective responsibility. An attempt is presented to configure the terms of a Portuguese post-colonial question with opaque outlines. This thesis reaches an open conclusion, articulated on the ever-present risk of appropriation of critical post-colonial categories by hegemonic ideology. The denunciation of racism as a permanent legacy and the reconfiguration of the colonial archive is a possible and necessary operation but not without risks.Esta tese investiga sobre a memória do "retorno" a partir duma uma perspetiva crítica que assume o “sul global de língua portuguesa” como espaço de referência histórica e conceptual. Reflete-se sobre a ideia de especificidade atribuída à colonização promovida por Portugal em África tendo em conta as contradições associadas ao movimento migratório desencadeado pelo violento processo de descolonização da África portuguesa.
As memórias traumáticas do retorno expõem a violência como componente constitutiva da realidade colonial mas também repropõem dinâmicas que permitem ocultar o racismo. A exploração do “sótão”, metáfora da memória doméstica, acompanha a do arquivo público. A análise do arquivo oficial e da memória familiar reflete a tentativa de estabelecer um diálogo entre história e memória superando a lógica da antítese que tradicionalmente as opõe.
Utilizando o conceito problemático de “pós-memória” reflecte-se sobre a reconfiguração da relação com o passado segundo uma ideia de “herança como tarefa” assumida pelo presente. A possibilidade de "salvar" o passado do desaparecimento progressivo de testemunhas envolve um perigo de abuso ideológico inerente ao processo de transmissão. A tradução das memórias coloniais sobre o regresso do espaço íntimo ao espaço do debate público mostra a relação entre a construção da mitologia familiar e a adoção do discurso lusotropical. A tentativa de definir o caráter indecifrável do retornado implica a possibilidade de sancionar a violência colonial negando uma responsabilidade coletiva referente ao colonialismo. Apresenta-se uma tentativa de configurar os termos de uma questão pós-colonial portuguesa com contornos opacos. Esta tese chega a uma conclusão aberta, articulada sobre o risco sempre presente de apropriação de categorias críticas pós-coloniais pela ideologia hegemônica. Através das (pós)memórias (pós)coloniais, a denúncia do racismo como legado permanente e a reconfiguração do arquivo colonial são operações possíveis, mas não por isso tomadas por garantidas ou sem riscos
Traditional nobleman's right and "international law" in the thought of Giovanni Giacomo Leonardi. With the edition of manuscripts "Il Principe Cavalliero in duello", "Il Cavalliero Ambasciatore" and "Pareri in materia di honore di Cavalleria pertinenti al duello"
Get PDFLa presente ricerca prende avvio dalla ricostruzione della biografia di Giovanni Giacomo Leonardi (1498-1562), pesarese, architetto militare, ambasciatore e cavaliere al servizio dei duchi d’Urbino Francesco Maria I (1490-1538) e Guidobaldo II (1514-1574) della Rovere. Attraverso lo spoglio delle fonti tra Pesaro, Firenze e Venezia, se ne è fornita una collocazione nel panorama politico-culturale dell’Italia cinquecentesca, al fine di evidenziare l’importanza del suo trattato in trentadue libri, intitolato "Il Principe Cavalliero", dedicato ai precetti dell’arte militare, diplomatica e cavalleresca necessari a formare il perfetto principe del tardo Rinascimento.
Dell’opera, rimasta inedita, sono state trascritte e studiate le parti dedicate alla scienza dell’onore e all’arte dell’ambasceria, al fine di dimostrare come i dettami della ‘religione di cavalleria’ influenzassero ogni ambito delle relazioni tra gentiluomini, comprese quelle interstatuali.The research starts from reconstruction of Giovanni Giacomo Leonardi's biography, as a military engineer, ambassador and knight, born in Pesaro, who served the dukes of Urbino Francesco Maria I (1490-1538) and Guidobaldo II (1514-1574) della Rovere. By the analysis of the sources between Pesaro, Florence and Venice, the thesis collocates Leonardi's figure in the Italian XVI century scenery, in order to mark the importance of his thirty-two books treaty, titled "Il Principe Cavalliero", dedicated to art of war, diplomacy and honor science.
As most of the original treaty has remained unpublished, the books concerning honor science and ambassery have been transcribed and studied in order to prove how effectively and efficiently the rules of "religione di cavalleria" were applied amidst gentlemen's and nations' relationships
Identification of new strategies for the evaluation of minimal residual disease in Multiple Myeloma: the Liquid Biopsy
Get PDFIl Mieloma Multiplo (MM) è una patologia neoplastica delle cellule B caratterizzata dalla proliferazione di più cloni di plasmacellule portatrici di diverse anomalie genomiche. Il MM presenta tipicamente un’eterogeneità genomica spaziale e intraclonale, che rende l’aspirato midollare "a singolo sito", attualmente utilizzato per la valutazione della malattia residua (MRD) dopo trattamento, non realmente informativo sulla taglia di malattia e sul panorama genomico della malattia. In considerazione della crescente importanza che sta assumendo la valutazione della MRD, i test per monitorarla dovrebbero essere non invasivi, affidabili e in grado di rappresentare le eterogeneità che caratterizzano il MM. Il presente studio ha permesso di dimostrare la possibilità di utilizzare la biopsia liquida, una metodica innovativa e non invasiva, per caratterizzare i pazienti con MM attivo o con MM smoldering ad alto rischio di evoluzione (HR-SMM) e per determinale l’MRD nei pazienti sottoposti a terapia di prima linea, integrando le metodiche attualmente validate. Nei pazienti arruolati nel presente studio è stato possibile identificare la frazione tumorale di DNA libero circolante (cfDNA-TF) nel sangue periferico, ed è stato possibile caratterizzare la malattia da un punto di vista qualitativo, dimostrando un’elevata concordanza del profilo genomico tra DNA libero circolante e DNA midollare (100% nei pazienti con HR-SMM e 86% nei pazienti con MM attivo). L’esecuzione seriata di biopsie liquide in corso di terapia, con un follow-up mediano di 24 mesi, ha mostrato una rapida e netta riduzione della cfDNA-TF xdalle prime fasi di terapia, con una tendenza a mantenersi mediamente sotto la soglia di sensibilità della metodica anche nelle fasi successive, indipendentemente dall’eventuale persistenza di MRD individuabile a livello midollare o mediante PET-CT. Con un follow-up più lungo probabilmente sarà possibile valutare meglio la capacità di questa metodica di affiancare o eventualmente sostituire l’aspirato midollare.Multiple myeloma (MM) is a neoplastic disease of B cells characterized by the proliferation of multiple plasma cell clones, typically with intraclonal and spatial genomic heterogeneity. This makes the "single site" bone marrow aspirate, currently used for the assessment of post-treatment residual disease (MRD), not fully informative of the disease burden and genomic landscape. MRD assessment is assuming a growing importance, so tests used to monitor it should be non-invasive, reliable and able to represent the heterogeneities that characterize MM. The present study has demonstrated the possibility of using liquid biopsy, an innovative and non-invasive method, to characterize patients with active MM or with smoldering MM at high risk of evolution (HR-SMM) at onset and to determine the 'MRD in patients that received first-line therapy, integrating the currently validated methods. In the patients enrolled in the present study it was possible to identify the tumor fraction of circulating free DNA (cfDNA-TF) in peripheral blood. It was also possible to qualitatively characterize the disease, demonstrating a high agreement of the genomic profile between circulating free DNA and bone marrow DNA (100% in patients with HR-SMM and 86% in patients with active MM). The serial execution of liquid biopsies during therapy, with a median follow-up of 24 months, permitted to evaluate the trend of cfDNA-TF, noting a rapid reduction from the early stages of therapy, with a tendency to remain below the sensitivity threshold of the method also in the subsequent phases, regardless of the possible persistence of MRD identifiable at the medullary level or by PET-CT. With a longer follow-up it will probably be possible to better evaluate the ability of this method to support or possibly replace bone marrow aspiration