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Stability issues in racing motorcycles: an in-depth analysis of the chatter vibration
Get PDFRacing motorcycles are prone to an unstable oscillatory motion of the swingarm and rear wheel, commonly known as ‘chatter’. This vibration mode typically has a frequency of 17 Hz to 22 Hz and typically occurs during heavy braking manoeuvres. The appearance of chatter can cause reduced rider confidence, and therefore lead to longer lap times during races and the increased risk of crashing. This thesis looks to further the understanding of this mode. It includes the development of a simplified model to explore the effects roll angle and lateral dynamics have on the chatter mode using linear analysis. The mechanisms of instability and parameter sensitivities are also examined. The effects of the nonlinearities present in the minimal model equations of motion are examined, including the identification of limit cycles and their stability, inspecting individual nonlinear terms and their effects, and introducing tyre relaxation and determining the effect it has on the dynamics. Finally, an exploratory study of the mid-corner region of a typical racing manoeuvre is performed in hopes to better understand if any high frequency tyre induced instabilities like chatter can occur
Evaluation and management of demersal stocks in the Adriatic: the case of common sole (Solea solea, L.) in the northern and central Adriatic Sea
Get PDFThis PhD thesis aimed to assess the status of common sole, one of the main commercial stocks in the Adriatic Sea, using a mix of conventional and innovative techniques to provide more reliable estimates of stock status compared to past advice. First, a meta-analysis was carried out using data-poor assessment model to analyze the whole catch assemblage of rapido fishery. The outcomes were used to estimate rebuilding time and forecast catches under different harvest control rule scenarios, with a reduction of 20% of fishing effort being suggested as a way to allow most of the species to recover to sustainable levels. Secondly, an ensemble of data-rich assessment models was developed to better incorporate uncertainty by using alternative hypotheses of main parameters. This was the first time an ensemble of models has been used in the Mediterranean to provide management advice. Consistent with data-poor analysis results, the ensemble outcomes indicated that the common sole stock was showing a recovering trend probably due to the effective management actions underway in the area rather than the moderate effort reduction according to the actual management plan. Moreover, back-calculation measurements were used to fit and compare monophasic and biphasic growth curves through the use of non-linear mixed effects models. The analyses revealed that the fitting of the biphasic curve was superior, confirming the theory that growth in size would decrease as a consequence of reproductive effort. A stock assessment simulation showed how the use of the monophasic pattern would result in a critical overestimation of biomass that could lead to a greater risk of overfishing. As a final step, a simulation-testing procedure was applied to determine the best performing reference points using stock-specific characteristic. The procedure could be routinely adopted to increase transparency in reference points calculation enhancing the credibility of scientific advice
Ancillary in vivo techniques to Mohs surgery: the role of the new technologies in the surgical margin evaluation of malignant cutaneous neoplasms
Get PDFLe neoplasie cutanee di tipo non-melanoma (non-melanoma skin cancers, NMSCs), quali il carcinoma a cellule basali (basal cell carcinoma, BCC) e il carcinoma a cellule squamose (squamous cell carcinoma, SCC) possono mostrare invasività locale e alto tasso di recidiva. La chirurgia microscopicamente controllata di Mohs (Mohs micrographic surgery, MMS) permette di eseguire una valutazione istologica immediata dei margini chirurgici delle neoplasie contestualmente alla loro escissione.
Nel nostro studio abbiamo valutato del ruolo delle tecnologie in vivo (dermatoscopia e microscopia confocale a riflettanza, MCR) nella definizione dei margini preoperatori di NMSC ad alto rischio del volto e descritto la nostra esperienza con chirurgia tradizionale e MMS. Sono stati valutati 234 pazienti operati nel triennio 2019-2021: 39 con MMS e guida videodermatoscopica (Gruppo 1) e 195 con chirurgia tradizionale e guida videodermatoscopica (Gruppo 2). I pazienti operati nel periodo 2013-2018 (con MMS, Gruppo 3 (n = 241), e con chirurgia tradizionale, Gruppo 4 (n = 1086)) sono stati usati come confronto. La radicalità chirurgica è stata ottenuta nel Gruppo 1 nel 92,3% dei casi, con 1,2 steps in media di MMS (versus 1,7 nel Gruppo 3), nel Gruppo 2 nell’84,5% dei casi. La percentuale di non radicalità è stata: 7,7% nel Gruppo 1, 15,9% nel Gruppo 2, 6,2% nel Gruppo 3, 17,9% nel Gruppo 4. I tassi di recidiva sono stati: 5,1% nel Gruppo 1, 3,6% nel Gruppo 2, 4,1% nel Gruppo 3, 5,9% nel Gruppo 4, soprattutto in BCC di tipo sclerodermiforme e infiltrante. La MCR prechirurgica è stata utilizzata in 11 pazienti, con alcuni limiti nel delineare BCC di tipo sclerodermiforme e infiltrante. In conclusione, la videodermatoscopia e la MCR appaiono valide tecniche ancillari alla MMS e anche alla chirurgia tradizionale nel trattamento dei NMSCs. La MMS appare indicata soprattutto nei pazienti giovani e salvaguarda l’outcome estetico e funzionale.Non-melanoma skin cancers (NMSCs) such as high risk basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) may be difficult to treat, due to a tendency to local tissue invasion and high recurrence rate.
Mohs micrographic surgery (MMS) allows margin mapping of the NMSC and immediate margin evaluation.
In our study we aimed to evaluate the role of videodermoscopy and reflectance confocal microscopy (RCM) in the preoperative evaluation of surgical margins of high risk NMSCs of the face; to describe our experience with traditional surgery and MMS.
We evaluated 234 patients treated in the years 2019-2022: 39 were operated with MMS assisted by videodermoscopy (Group 1), 195 with traditional surgery assisted by videodermoscopy (Group 2). Data were compared with patients treated in the years 2013-2018 (with MMS, Group 3 (n = 241) and with traditional surgery, Group 4 (n = 1086)).
Radical excision was obtained in 92,3% of cases in Group 1, with a mean of 1,2 steps of MMS (versus 1,7 in Group 3), and in 84,5% of cases in Group 2.
Groups 1 and 3 showed similar rates of incomplete excision (7,7% and 6,2%), while Group 2 showed a sensible reduction of incomplete excision rate compared with Group 4 (15,9% versus 17,9%).
Recurrence rates were: 5,1% in Group 1, 3,6% in Group 2, 4,1% in Group 3, 5,9% in Group 4.
Recurrence was common in infiltrative and morpheiform BCCs, in elderlies and male patients.
In conclusion, videodermoscopy and MCR, even if more recent, represent valid ancillary techniques to both MMS and traditional surgery. MMS is mostly suitable for young patients and guarantees an acceptable cosmetic and functional outcome
Optoelectronic investigation of defects in hybrid metal halide perovskites
Get PDFThe growing demand for flexible and low-cost electronics has driven research towards the study of novel semiconducting materials to replace traditional semiconductors like silicon and germanium, which are limited by mechanical rigidity and high production cost. Some of the most promising semiconductors in this sense are metal halide perovskites (MHPs), which combine low-cost fabrication and solution processability with exceptional optoelectronic properties like high absorption coefficient, long charge carrier lifetime, and high mobility. These properties, combined with an impressive effort by many research groups around the world, have enabled the fabrication of solar cells with record-breaking efficiencies, and photodetectors with better performance than commercial ones. However, MHP devices are still affected by issues that are hindering their commercialization, such as degradation under humidity and illumination, ion migration, electronic defects, and limited resistance to mechanical stress. The aim of this thesis work is the experimental characterization of these phenomena. We investigated the effects of several factors, such as X-ray irradiation, exposure to environmental gases, and atmosphere during synthesis, on the optoelectronic properties of MHP single crystals. We achieved this by means of optical spectroscopy, electrical measurements, and chemical analyses. We identified the cause of mechanical delamination in MHP/silicon tandem solar cells by atomic force microscopy measurements. We characterized electronic defects and ion migration in MHP single crystals by applying for the first time the photo-induced current transient spectroscopy technique to this class of materials. This research allowed to gain insight into both intrinsic defects, like ion migration and electron trapping, and extrinsic defects, induced by X-ray irradiation, mechanical stress, and exposure to humidity. This research paves the way to the development of methods that heal and passivate these defects, enabling improved performance and stability of MHP optoelectronic devices
Characterization of pyrolysis and oxidation processes of biomaterials, biomasses and biofuels
Get PDFThe urgent need for alternative solutions mitigating the impacts of human activities on the environment has strongly opened new challenges and opportunities in view of the energy transition. Indeed, the automotive industry is going through a revolutionary moment in its quest to reduce its carbon footprint, with biofuels being one of the viable alternatives. The use of different classes of biofuels as fuel additives/standalone components has attracted the attention of many researchers. Despite their beneficial effects, biofuel’s combustion can also result in the production of undesirable pollutants, requiring complete characterization of the phenomena occurring during their production and consumption. Industrial scale-up of biomass conversion is challenging owing to the complexity of its chemistry and transport phenomena involved in the process. In this view, the role of solid-phase and gas-phase chemistry is paramount. Thus, this study is devoted to detailed analysis of physical-chemical phenomena characterizing biomass pyrolysis and biofuel oxidation. The pyrolysis mechanism has been represented by 20 reactions whereas, the gas-phase kinetic models; manually upgraded model (KiBo_MU) and automated model (KiBo_AG), comprises 141 species and 453 reactions, and 631 species and 28329 reactions, respectively. The accuracy of the kinetic models was tested against experimental data and the models captured experimental trends very well.
While the development and validation of detailed kinetic mechanisms is the main deliverable of this project, the realized procedure integrating schematic classifications with methodologies for the identification of common decomposition pathways and intermediates represents an additional source of novelty. Besides, the fundamentally oriented nature of the adopted method allows the identification of most relevant reactions and species under the operating conditions different industrial applications, paving the way for reduced kinetic mechanisms. Ultimately, the resulting detailed mechanisms can be used to integrate with more complex fluid dynamics model to accurately reproduce the behavior of real systems and reactors
Ordinary civil jurisdiction and independent administrative authorities in the integrated system of rights protection
Get PDFL’elaborato si propone di analizzare i principali punti di contatto, nell’ordinamento domestico, tra le funzioni esercitate dalla giurisdizione ordinaria civile e le attribuzioni delle Autorità amministrative indipendenti, nel tentativo di delineare un quadro sistematico dei rapporti. Nella prima parte dell’indagine, ci si sofferma sui variegati strumenti di risoluzione delle controversie coniati in seno alle Autorità indipendenti, cercando di sviluppare un’essenziale classificazione per categorie omogenee, al fine di vagliare la compatibilità dei diversi modelli con il dato costituzionale. Successivamente, si sposta l’indagine sulle interferenze emergenti con riferimento a quelle attività delle Authorities assimilabili all’applicazione della legge al caso concreto nel contesto del pubblic enforcement. Tra queste, spicca la delicata questione del valore dei provvedimenti delle Authorities nei (correlati) processi civili risarcitori, soprattutto a seguito dell’entrata in vigore dell’art. 7, d.lgs. 3/2017, che ha plasmato un inedito «vincolo» per il giudice ordinario all’accertamento dell’AGCM. Alla previsione normativa si associa la tendenza giurisprudenziale a riconoscere una particolare “attitudine probatoria” anche ai provvedimenti di altre Autorità indipendenti, pur in assenza di specifica previsione normativa. Nel corso della trattazione, più che limitarsi ad esprimere una preferenza tra le diverse soluzioni già proposte dalla dottrina, si cerca di gettare le basi per un’interpretazione autonoma e sistematica del fenomeno. Adottando un approccio quanto più possibile interdisciplinare, si cercano di coniugare i punti di approdo della teoria generale dell’accertamento giuridico con quelli, gius-pubblicistici, della categoria dell’accertamento amministrativo. Si passa, infine, a vagliare le condizioni affinché tale ipotetico modello unitario possa ritenersi compatibile con altri valori di rilievo costituzionale e non solo, utilizzando quale parametro di riferimento l’art. 6 Cedu, come interpretato dalla Corte di Strasburgo.The aim of this paper is to analyze the main points of contact, in the domestic system, between the functions exercised by the civil ordinary jurisdiction and the powers of the Independent Authorities, in an attempt to outline a systematic framework of such interaction.
The first part of the research focuses on the several dispute resolution tools developed within the Independent
Authorities, by shaping a classification in homogeneous categories in order to assess the compatibility of such emerging models with the constitutional framework.
Subsequently, the investigation shifts to the emerging interferences of certain activities of the Authorities that can be compared to the application of the law to the concrete case in the context of public enforcement. Among them, it is worthy mentioning the delicate issue of the value of the Authorities'decisions in (related) tort trials, especially following the adoption of Article 7, of the Legislative Decree no. 3, dated 19/01/2017, wich provided for an unprecedented "constraint" for the civil courts to the AGCM's (Italian Competition Authority) findings. Further to the legal provision, it has been developed judicial tendency to give a particular proof status also to the decisions of other Independent Authorities, even in the absence of specific positive provisions.
This paper, rather than expressing a preference among the different interepretations of the doctrine, attempts the effort to lay the ground for an autonomous and systematic interpretation of the phenomenon. This thesis aims at combining the converging points of the general ascertainment theory with the category of administrative ascertainment,
adopting the widest interdisciplinary approach possible. Finally, this study examines the conditions set for such a
hypothetical unitary model to comply with other values of constitutional importance and beyond, using as a benchmark
the interpretation given by the Strasbourg Court to Article 6 of the ECHR
Inhibition and characterization of two-metal ion enzymes to treat cancer: dna polymerase Ƞ and topoisomerase II α
Get PDFChemotherapeutic drugs can in many ways disrupt the replication machinery triggering apoptosis in cancer cells: some act directly on DNA and others block the enzymes involved in preparing DNA for replication. Cisplatin-based drugs are common as first-line cancer chemotherapics. Another example is etoposide, a molecule that blocks topoisomerase II α leading to the inhibition of dsDNA replication. Despite their efficacy, cancer cells can respond to these treatments over time by overtaking their effects, leading to drug resistance. Chemoresistance events can be triggered by the action of enzymes like DNA polymerase ƞ (Pol η). This polymerase helps also to bypass drug-induced damage in cancer cells, allowing DNA replication and cancer cells proliferation even when cisplatin-based chemotherapeutic drugs are in use. Pol ƞ is a promising drug discovery target, whose inhibition would help in overcoming of drug resistance.
This study aims to identify a potent and selective Pol ƞ inhibitor able to improve the efficacy of platinum-based chemotherapeutic drugs. We report the discovery of compound 64 (ARN24964), after an extensive SAR reporting 35 analogs. We evaluated compound 64 on four different cell lines. Interestingly, the molecule is a Pol η inhibitor able to act synergistically with cisplatin. Moreover, we also synthesized a prodrug form that allowed us to improve its stability and the bioavailability. This compound represents an advanced scaffold featuring good potency and DMPK properties.
In addition to this central theme, this thesis also describes our efforts in developing and characterize a novel hybrid inhibitor/poison for the human topoisomerase II α enzyme. In particular, we performed specific assays to study the inhibiton of Topoisomesare II α and we evaluated compounds effect on three cancer cell lines. These studies allowed us to identify a compound that is able to inhibit the enzyme with a good pK and a good potency
Motion event encoding in Russian in contrast with Italian: the role of prefixation and its means of expression in Italian.
Get PDFВ данной работе рассматривается лексикализация события движения в русском языке в сопоставлении с итальянским. Цель нашей работы двойная: с одной стороны, мы рассмотрим пространственную семантику выбранных нами глагольных префиксов и определим их семантический вклад в лексикализацию события движения. С другой стороны, мы проанализируем соответствия русских приставочных глаголов движения при переводе на итальянский язык. В частности, мы сосредоточимся на том, выражается ли вклад префикса, передается ли он полностью или частично, какие нюансы его пространственной семантики могут опускаться, а какие выражаются обязательно и какими языковыми средствами.
Работа состоит из введения, трех глав и заключения. В Первой главе представляется теоретическая рамка, на которую опирается сопоставительный анализ. Рассматриваются понятия движения и перемещения согласно семантическим толкованиям, приведенным как в русскоязычной литературе, так и в работах на других языках. Кроме того, концептуализация пространства описывается в русле когнитивного подхода к изучению языка. Представлена классификация языков по лексикализации события движения, введенной Л. Талми, а также основные последующие исследования, посвященные лексикализации события движения в различных языках, проведенные в русле типологического подхода. Отдельный параграф первой главы посвящается вкладу исследований, проведенных Д. Слобиным в области лексикализации компонентов движения, в частности, способа движения в различных языках.
Во Второй главе описываются система бесприставочных глаголов движения в русском языке и основные подходы к их изучению. Регулярно проводятся параллели с итальянской системой глаголов движения. Далее в этой главе представлен обзор системы приставочных глаголов движения русского языка. Отдельно мы рассматриваем главные подходы к изучению семантики глагольных префиксов, фокусируясь на их пространственных значениях. В Третьей главе представляется подбор глагольных префиксов с пространственной семантикой, выбранных для целей сопоставительного анализа. Для каждого префикса предлагается словарное толкование, описывается его пространственная семантика согласно концепциям, разработанным различными авторами, и проводится анализ контекстов употребления приставочных глаголов в русском языке и возможные стратегии их передачи на итальянский язык. Выводы изложены в заключении, прилагается также список литературы.The encoding of motion events has been and is the focus of numerous studies from both a typological and a cognitive perspective. Our work builds on the research conducted by Leonard Talmy and other scholars such as Dan I. Slobin in the description of the components of a motion event and the study of their expression from a cross-linguistic point of view.
Starting from the classification proposed by Leonard Talmy, according to which languages can be traced back to two models of lexicalisation of the path of motion (satellite languages vs. verb-framed languages), in the course of the contrastive analysis it is observed how Russian and Italian, which can be traced back to the group of satellite languages and verb-framed languages respectively, can encode the components of a motion event in different ways. Particular attention is devoted to the role of verbal prefixation in the expression of the path of motion.
Our work is composed as follows: an introduction, three chapters, conclusions and a reference list. The first chapter is devoted to presenting the state of the art and the theoretical framework that supports our contrastive study. The second chapter describes the linguistic means available to the two languages considered for expressing a motion event. The third chapter presents the contrastive analysis based on examples from the parallel Russian-Italian corpus of the National Corpus of the Russian Language. In the course of our contrastive analysis, two important facts emerge: the complex spatial semantics of Russian verbal prefixes characterised by the presence of several components that may or may not activate depending on the context, and the variety of strategies that can be applied in Italian to convey the semantics of Russian prefixed verbs of motion
Governing the water conservation in the Urmia Lake Basin: addressing macro systems’ fit and micro users’ behavior
Get PDFTo change unadapted water governing systems, and water users’ traditional conducts in line with climate change, understanding of systems’ structures and users’ behaviors is necessary. To this aim, comprehensive and pragmatic research was designed and implemented in the Urmia Lake Basin where due to the severe droughts, and human-made influences, especially through the agricultural development, the lake has been shrunken drastically. To analyze the water governance and conservation issues in the basin, an innovative framework was developed based on mathematical physics concepts and pro-environmental behavior theories. Accordingly, in system level (macro/meso), the problem of fit of the early-shaped water governing system associating with the function of “political-security” and “political-economic” factors in the basin was identified through mean-field models. Furthermore, the effect of a “political-environmental” factor, the Urmia Lake Restoration Program (ULRP), on reforming the system structure and hence its fit was assessed. The analysis results revealed that by revising the provincial boundaries (horizontal alternation) for the entity of Kurdistan province to permit that interact with the headquarter of West Azerbaijan province for its water demand-supply initiatives, the system fit can increase. Also, the constitution of the ULRP (vertical arrangement) not only could increase the structural fit of the water governing system to the basin, but also significantly could enhance the system fit through its water-saving policy. Besides, in individual level (micro), the governing factors of water conservation behavior of the major users/farmers were identified through rational and moral socio-psychological models. In rational approach, incorporating PMT and TPB, the SEM results demonstrated that “Perceived Vulnerability”, “Self-Efficacy”, “Response Efficacy”, “Response Cost”, “Subjective Norms” and “Institutional Trust” significantly affect the water-saving intention/behavior. Likewise, NAM based analysis as a moral approach, uncovered the significant effects of “Awareness of Consequences”, “Appraisal of Responsibility”, “Personal Norms” as well as “Place Attachment” and “Emotions” on water-saving intention
Oto-Bio-Graphies: auditory perception in twentieth-century self-narratives
Get PDFThroughout the twentieth century, the study of auditory perception emerged as a significant area of inquiry across various disciplines, particularly within the fields of poststructuralism and psychoanalysis. These theories converge in their understanding of hearing as a fundamental aspect of the development of the subject, leading to a decentering and reformulation of the autobiographical subject, suggesting that the rhythmic is a state of being outside of and prior to the social, verbal, thinking subject. This research aims to examine the connection between auditory perception and the formation of subjectivity in twentieth-century self-narratives. Drawing both from psychoanalysis and poststructuralism, this research proposes a reading of three autobiographical works, namely Elias Canetti’s Die gerettete Zunge, Nathalie Ginzburg’s Lessico famigliare and Nathalie Sarraute’s Enfance. By highlighting the importance of the voice and of the sonorous envelope of childhood, these works artistically anticipate what would be theorised only a few decades later and create the conditions for a pre-verbal apprehension of the world, raising questions about the ineffable source of writing and the writing process itself