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Anatomopathological diagnostics in swine infectious diseases: limits and usefulness of pathogen-lesion co-localization
Get PDFIl processo di intensificazione dell’allevamento suinicolo ha comportato conseguenze importanti dal punto di vista sanitario. Nei moderni sistemi di produzione la salute è compromessa a causa di malattie multifattoriali e l'identificazione degli agenti casuali di malattia non può basarsi esclusivamente sul risultato di un unico test diagnostico. La maggior parte dei patogeni è ubiquitaria, quindi l'identificazione di un agente infettivo suggerisce solo una possibile diagnosi.
La patologia gioca un ruolo chiave nel determinare la causalità nella diagnosi delle malattie infettive. L'istopatologia consente di correlare la presenza dell'agente infettivo con le lesioni microscopiche caratteristiche: in base alla disponibilità di anticorpi o sonde per rilevare rispettivamente la presenza di antigeni o del genoma di virus o batteri nelle sezioni istologiche, l'istopatologia è utile per determinare il nesso causale con la malattia.
L'introduzione di questa tesi è incentrata sulla discussione del ruolo della patologia nelle malattie infettive del suino, seguita dalla descrizione del corretto campionamento per l'esame istopatologico nella diagnosi delle malattie respiratorie, enteriche e riproduttive.
La sezione sperimentale riporta i risultati delle indagini diagnostiche in patologia suina condotte per definire il ruolo di PCV2 e PRRSV nel complesso delle malattie respiratorie del suino (PRDC)(capitolo 2) e per definire un percorso diagnostico per l'enteropatia proliferativa suina causata da Lawsonia intracellularis ai fini dell'implementazione dell'accuratezza diagnostica (capitolo 3).
Il capitolo 4 descrive l'uso dell'istopatologia come componente metodologica essenziale per valutare l'efficacia protettiva dei vaccini negli studi di challenge vaccinazione-infezione. Il capitolo descrive i risultati ottenuti in due successive sperimentazioni per valutare l'efficacia di due vaccini sperimentali per PCV2, il primo formulato con ceppo PCV2b inattivato somministrato a differenti dosi di antigene; il secondo formulato con antigene "Cap" ricombinante non assemblato in particelle simil-virali (VLP).The intensification of pig farming has led to serious health implication. In modern production systems health is impaired due to multifactorial diseases and the identification of the causal agent cannot be based exclusively on the result of a single diagnostic tool. Most pathogens are ubiquitous, so the identification of an infectious agent suggests only a possible diagnosis.
Pathology plays a key role in determining causality in the diagnosis of infectious diseases. Histopathology allows to correlate the presence of the infectious agent with the characteristic microscopic lesions: based on the availability of antibodies or probes to detect respectively the presence of antigens or the genome of viruses or bacteria in histological sections, histopathology is useful for determining the causal link with the disease.
The introduction of this thesis is focused on the role of pathology in infectious diseases of swine followed by a discussion on the proper sampling for histopathological examination in the diagnosis of respiratory, enteric and reproductive diseases.
The experimental section reports the results of diagnostic investigations in porcine pathology conducted to define the role of PCV2 and PRRSV in Porcine respiratory disease complex (PRDC) (chapter 2) and to define a diagnostic pathway for porcine proliferative enteropathy caused by Lawsonia intracellularis to improve the diagnostic accuracy (chapter 3).
Chapter 4 describes the use of histopathology as an essential methodological component to evaluate the protective efficacy of vaccines in vaccine challenge studies. The chapter describes the results obtained in two subsequent trials to evaluate the efficacy of two experimental vaccines for PCV2, the first formulated with inactivated PCV2b strain administered at different doses of antigen; the second formulated with recombinant "Cap" antigen not assembled in virus-like particles (VLP)
Civic education and citizenship competences: a survey on secondary school teachers' attitudes and approaches
Get PDFCon questo lavoro si vuole contribuire al dibattito riapertosi con il ritorno dell’Educazione civica in tutte le scuole italiane, a seguito dell’entrata in vigore della Legge 92/2019, in particolare valorizzando il punto di vista degli insegnanti. La ricerca è impostata secondo il disegno quantitativo dell’indagine correlazionale su ampio campione, preparata da una fase esplorativa durante la quale si sono svolte interviste semistrutturate a dieci docenti. A partire dai risultati di tale esplorazione, si è prodotto un questionario che è stato testato e revisionato nell’a.s. 2020-2021. Successivamente si sono condotte due diverse rilevazioni nell’a.s. 2021-2022: la prima su un campione rappresentativo degli insegnanti di scuola secondaria dell’Emilia-Romagna (main study), e la seconda su un campione non rappresentativo su base nazionale (rilevazione di approfondimento). I risultati dell’indagine fanno emergere un’accoglienza parziale delle innovazioni introdotte con la “nuova” Educazione civica. Le maggiori difficoltà si osservano rispetto alla progettazione collegiale dell’insegnamento, che la normativa vorrebbe affidato in contitolarità a tutto il Consiglio di classe, ma rispetto al quale sembra realizzarsi principalmente una “spartizione” delle ore, a cui fanno fronte attività gestite separatamente dai singoli insegnanti. Approcci e pratiche coerenti con i modelli della didattica per competenze tardano ad affermarsi per questo insegnamento, nonostante si siano osservate prime evidenze favorevoli in tal senso. I risultati sollevano il bisogno di maggiore accompagnamento e supporto dei docenti nell’implementazione collegiale di un curricolo di Educazione civica intenzionalmente orientato allo sviluppo delle competenze di cittadinanza.With this work, we aim to participate in the debate following the reintroduction of Civic Education in the Italian school system (Law 92/2019). The research goal is to build empirical evidence on teachers' points of view about this reintroduction, focusing on secondary-school teachers. At the same time, we try to elaborate suggestions on instructional design and assessment practices in coherence with the literature on citizenship competencies. The research is a quantitative survey on a large sample, but we also planned some qualitative moments to better detail teachers' opinions, beliefs, and attitudes. The survey was conducted in a.y. 2021-2022 and a questionnaire was administered to two samples of teachers: the regional sample (main study) and the national one (supplementary study). The regional sample was selected with a randomized procedure. The results of this study highlight an incomplete acceptance of the innovations of the "new" Civic Education. Teachers' answers show difficulties regarding the instructional design of the curriculum for this subject, due to a lack of cooperation between teachers of the same staff. Teachers are not used to working together on a common definition of educational goals and instructional activities for Civic Education. Also, the results show a lack of knowledge regarding the concept of "competence" and its significance for educational approaches and practices; in particular, teachers seem to be partially resistant to innovations in the field of curriculum design and evaluation practices for the development of competencies. The results point out the need for support and professional education for teachers, in particular on what concerns instructional design for the development of citizenship competencies, and their assessment. More in-depth studies in the field of Teacher Change are needed, to better understand the relationship between teachers' attitudes toward changes, objective and organizational restrictions, and the adoption of innovative practices in class
Oscillatory mechanisms of conscious perception and attention
Get PDFAlthough the prominent role of neural oscillations in perception and cognition has been continuously investigated, some critical questions remain unanswered. My PhD thesis was aimed at addressing some of them.
First, can we dissociate oscillatory underpinnings of perceptual accuracy and subjective awareness? Current work would strongly suggest that this dissociation can be drawn. While the fluctuations in alpha-amplitude decide perceptual bias and metacognitive abilities, the speed of alpha activity (i.e., alpha-frequency) dictates sensory sampling, shaping perceptual accuracy.
Second, how are these oscillatory mechanisms integrated during attention? The obtained results indicate that a top-down visuospatial mechanism modulates neural assemblies in visual areas via oscillatory re-alignment and coherence in the alpha/beta range within the fronto-parietal brain network. These perceptual predictions are reflected in the retinotopically distributed posterior alpha-amplitude, while perceptual accuracy is explained by the higher alpha-frequency at the to-be-attended location. Finally, sensory input, elaborated via fast gamma oscillations, is linked to specific phases of this slower activity via oscillatory nesting, enabling integration of the feedback-modulated oscillatory activity with sensory information.
Third, how can we relate this oscillatory activity to other neural markers of behaviour (i.e., event-related potentials)? The obtained results favour the oscillatory model of ERP genesis, where alpha-frequency shapes the latency of early evoked-potentials, namely P1, with both neural indices being related to perceptual accuracy. On the other hand, alpha-amplitude dictates the amplitude of later P3 evoked-response, whereas both indices shape subjective awareness.
Crucially, by combining different methodological approaches, including neurostimulation (TMS) and neuroimaging (EEG), current work identified these oscillatory-behavior links as causal and not just as co-occurring events. Current work aimed at ameliorating the use of the TMS-EEG approach by explaining inter-individual differences in the stimulation outcomes, which could be proven crucial in the way we design entrainment experiments and interpret the results in both research and clinical settings
Deep and near space tracking stations in support of lunar and planetary exploration missions
Get PDFThe aim of this dissertation is to describe the methodologies required to design, operate, and validate the performance of ground stations dedicated to near and deep space tracking, as well as the models developed to process the signals acquired, from raw data to the output parameters of the orbit determination of spacecraft. This work is framed in the context of lunar and planetary exploration missions by addressing the challenges in receiving and processing radiometric data for radio science investigations and navigation purposes. These challenges include the designing of an appropriate back-end to read, convert and store the antenna voltages, the definition of appropriate methodologies for pre-processing, calibration, and estimation of radiometric data for the extraction of information on the spacecraft state, and the definition and integration of accurate models of the spacecraft dynamics to evaluate the goodness of the recorded signals. Additionally, the experimental design of acquisition strategies to perform direct comparison between ground stations is described and discussed. In particular, the evaluation of the differential performance between stations requires the designing of a dedicated tracking campaign to maximize the overlap of the recorded datasets at the receivers, making it possible to correlate the received signals and isolate the contribution of the ground segment to the noise in the single link. Finally, in support of the methodologies and models presented, results from the validation and design work performed on the Deep Space Network (DSN) affiliated nodes DSS-69 and DSS-17 will also be reported
The principle of good faith applied in public administration activities
Get PDFL’applicazione del principio di buona fede oggettiva all’attività della pubblica amministrazione, sia contrattuale che provvedimentale, è attualmente fuori discussione, tuttavia i limiti e le modalità attraverso cui questo principio si articola sono ancora oggetto di dibattito dottrinale e giurisprudenziale, in particolare modo per quanto riguarda l’istituto della responsabilità precontrattuale della p.a.
Tale ultimo istituto è oggetto di uno specifico approfondimento, che tenterà di analizzare i principali punti cruciali del dibattito: la tutela del legittimo affidamento del privato durante le trattative instaurate con la p.a., la natura giuridica della responsabilità precontrattuale e questioni di stampo più processuale, come il riparto di giurisdizione tra giudice ordinario e amministrativo.
Al fine poi di comprendere pienamente le funzioni svolte dal principio di buona fede nell’ambito delle attività pubbliche, sia contrattuali che autoritative, la ricerca si è concentrata anche sulle diverse interpretazioni che gli studiosi del diritto hanno attribuito oggi al giudizio di buona fede, inteso sia come principio civile contrattuale che come nuovo principio amministrativo costituzionalmente orientato.
Nel proseguo della dissertazione, infatti, si cerca di valutare l’applicabilità del giudizio di buona fede da un punto di vista interdisciplinare, civile e amministrativo, allo scopo di dimostrare come tale principio sia riuscito lentamente a pervadere anche la materia amministrativa, condizionando in senso garantista non solo il dictum giurisprudenziale, ma anche l’intervento normativo del legislatore.The application of good faith's principle to the activity of the public administration, intended both as contractual and procedural, is currently undeniable, however the limits and modalities through which this principle is articulated are still the subject of doctrinal and jurisprudential debate, in particular as regards the institution of the pre-contractual liability of the public administration
This latter institute is the subject of a specific analysis, which will attempt to investigate the main crucial points of the debate: the protection of the legitimate expectations of the private individual during the negotiations established with the public administration, the legal nature of pre-contractual liability and more procedural issues, such as the division of jurisdiction between civil and administrative law judges.
In order then to fully understand the functions performed by the principle of good faith in the context of public activities, the research also concentrated on the different interpretations that legal scholars have today attributed to the judgment of good faith, understood both as a civil contractual principle and as a new constitutionally oriented administrative principle.
In the continuation of the dissertation, in fact, an attempt is made to evaluate the applicability of the judgment of good faith from an interdisciplinary, civil and administrative point of view, in order to demonstrate how this principle has slowly managed to pervade administrative matters as well, influencing in a sense guaranteed not only the jurisprudential dictum, but also the normative intervention of the legislator
Hydrodynamic simulations of multiple stellar populations in globular clusters
Get PDFThe presence of multiple stellar populations in globular clusters (GCs) is now well accepted, however, very little is known regarding their origin. In this Thesis, I study how multiple populations formed and evolved by means of customized 3D numerical simulations, in light of the most recent data from spectroscopic and photometric observations of Local and high-redshift Universe. Numerical simulations are the perfect tool to interpret these data: hydrodynamic simulations are suited to study the early phases of GCs formation, to follow in great detail the gas behavior, while N-body codes permit tracing the stellar component.
First, we study the formation of second-generation stars in a rotating massive GC. We assume that second-generation stars are formed out of asymptotic giant branch stars (AGBs) ejecta, diluted by external pristine gas. We find that, for low pristine gas density, stars mainly formed out of AGBs ejecta rotate faster than stars formed out of more diluted gas, in qualitative agreement with current observations.
Then, assuming a similar setup, we explored whether Type Ia supernovae affect the second- generation star formation and their chemical composition. We show that the evolution depends on the density of the infalling gas, but, in general, an iron spread is developed, which may explain the spread observed in some massive GCs.
Finally, we focused on the long-term evolution of a GC, composed of two populations and orbiting the Milky Way disk. We have derived that, for an extended first population and a low-mass second one, the cluster loses almost 98 percent of its initial first population mass and the GC mass can be as much as 20 times less after a Hubble time. Under these conditions, the derived fraction of second-population stars reproduces the observed value, which is one of the strongest constraints of GC mass loss
Ethnicity and cross-border lending: evidence from the syndicated loan market.
Get PDFWhilst the connection between culture and financial intermediation across countries has received considerable
attention, there is scant work on the role of local ethnicity in bank lending operations. To fill this void, we lean
on the sociology literature to scrutinize the impact of local ethnicity characteristics on syndicated loan
composition and size in cross-border lending. We specifically examine whether local demographics in the U.S.
for a specific bank impact their contracting in the international syndicated loan market. Exploiting Gravity
Models, we find a higher likelihood of syndication and volume in cross-border loans when there is overlap in
local and foreign market ethnicity. To alleviate endogeneity concerns between ethnicity and bank lending, we
conduct robustness tests on different sub-samples. This analysis reports a significant uptick in cross-border
loans for merging banks which share ethnicity in their neighbourhood (or zip). Moreover, these loans are
associated with lower spreads than other matched cross-border loans, which can be explained by lower
asymmetric information
A phase II, single arm study of CarbopLatin plus Etoposide with Bevacizumab and Atezolizumab in patients with exTEnded-disease small-cell lung cancer (SCLC) – CeLEBrATE trial
Get PDFSmall cell lung cancer (SCLC) is an aggressive neuroendocrine tumor diagnosed at extended disease SCLC (ES-SCLC) stage in about 70% of cases. The new standard of treatment for patients with ES-SCLC is a combination of platinum-etoposide chemotherapy and atezolizumab or durvalumab, two programmed cell death ligand 1 (PD-L1) inhibitory monoclonal antibodies (mAb). However, the benefit derived from the addition of PD-L1 inhibitors to chemotherapy in ES-SCLC was limited and restricted to a subset of patients. The vascular endothelial growth factor (VEGF) is the most important pro-angiogenic factor implicated in cancer angiogenesis, which is abundant in SCLC and associated with poor prognosis. Antiangiogenic agents, such as bevacizumab, a humanized mAb against VEGF, added to platinum-etoposide chemotherapy improved progression-free survival in SCLC in two trials, but it did not translate into a benefit in overall survival. Nevertheless, VEGF has also acts as a mediator of an immunosuppressive microenvironment and its inhibition can revert the immune-suppressive tumor microenvironment and potentially enhance the efficacy of immunotherapies. Based on available preclinical data, we hypothesized that VEGF inhibition by bevacizumab could improve atezolizumab efficacy in a synergistic way and designed a phase II single-arm trial of bevacizumab in combination with carboplatin, etoposide, and atezolizumab as first-line treatment in ES-SCLC. The trial, which is still ongoing, enrolled 53 patients, including those with treated or untreated asymptomatic brain metastases (provided criteria are met), who received atezolizumab, bevacizumab, carboplatin and etoposide for 4-6 cycles (induction phase), followed by maintenance with atezolizumab and bevacizumab for a maximum of 18 total cycles or until disease progression, patient refusal, unacceptable toxicity. The evaluation of efficacy of the experimental combination in terms of 1-year overall survival rate is not yet mature (primary objective of the trial). The combination was feasible and the toxicity profile manageable (secondary objective of the trial)
A novel hybrid thermochemical-biological refinery integrated with power-to-X approach for obtaining biopolymers
Get PDFIn this study, a novel hybrid thermochemical-biological refinery integrated with power-to-x approach was developed for obtaining biopolymers (namely polyhydroxyalkanoates, PHA). Within this concept, a trilogy process schema comprising of, (i) thermochemical conversion via integrated pyrolysis-gasification technologies, (ii) anaerobic fermentation of the bioavailable products obtained through either thermochemistry or water-electrolysis for volatile fatty acids (VFA) production, (iii) and VFA-to-PHA bioconversion via an original microaerophilic-aerobic process was developed. During the first stage of proposed biorefinery where lignocellulosic (wooden) biomass was converted into, theoretically fermentable products (i.e. bioavailables) which were defined as syngas and water-soluble fraction of pyrolytic liquid (WS); biochar as a biocatalyst material; and a dense-oil as a liquid fuel. Within integrated pyrolysis - gasification process, biomass was efficiently converted into fermentable intermediates representing up to 66% of biomass chemical energy content in chemical oxygen demand (COD) basis. In the secondary stage, namely anaerobic fermentation for obtaining VFA rich streams, three different downstream process were investigated. First fermentation test was acidogenic bioconversion of WS materials obtained through pyrolysis of biomass within an original biochar-packed bioreactor, it was sustained up to 0.6 gCOD/L-day volumetric productivity (VP). Second, C1 rich syngas materials as the gaseous fraction of pyrolysis-gasification stage, was fermented within a novel char-based biofilm sparger reactor (CBSR), where up to 9.8 gCOD/L-day VP was detected. Third was homoacetogenic bioconversion within the innovative power-to-x pathway for obtaining commodities via renewable energy sources. More specifically, water-electrolysis derived H2 and CO2 as a primary greenhouse gas was successfully bio-utilized by anaerobic mixed cultures into VFA within CBSR system (VP: 18.2 gCOD/L-day). In the last stage of the developed biorefinery schema, VFA is converted into biopolymers within a new continuous microaerophilic-aerobic microplant, where up to 60% of PHA containing sludges was obtained
Performatic ecosystems: from frontality to immersivity (and back)
Get PDFQuesta ricerca si concentra sui modi di produzione e ricezione della teatralità nelle pratiche performative contemporanee con finalità estetiche. In particolare, sono indagate quelle pratiche che – all’interno di ecosistemi performátici – impiegano modalità di progettazione dell’azione ricorrendo a strategie e dispositivi di teatralizzazione dell’evento attraverso modelli immersivi co-partecipativi, intervenendo sui meccanismi semiocognitivi di interpretazione dello spettatore. Il concetto di ecosistemi performátici consente di pertinentizzare le differenti formazioni semiotiche che emergono dal continuum performativo della semiosfera, cogliendo i rapporti ecologici ed evolutivi che si instaurano diacronicamente tra le forme teatrali. Sono soprattutto le trasformazioni a essere comprese, restituendo all’analisi semiotica un’immagine delle arti performátiche dinamica e radicata nella cultura e nella società, e delle modalità in cui i meccanismi di base della teatralità prendono forma. Con approccio etnografico ecologico cognitivo, si affronta il tema della corporeità e dei regimi di presenza, introducendo nell’analisi relazionale il concetto di emplacement a integrazione della nozione di embodiment. È elaborato, inoltre, un modello autopoietico dell’enunciazione come atto di mostrazione, sulla metafora della “conversazione”. Nell’ecologia dell’ambiente performático tra attore e spettatore si crea un “campo interattivo”, nel quale si consuma l’enunciazione teatrale. Attraverso casi studio, si illustra come le esperienze immersive co-partecipative scardinano e riconfigurano l’insieme di norme e usi naturalizzati nella tradizione teatrale occidentale del dramma. Si giunge, infine, a concepire la relazione tra frontalità e immersività non in termini di opposizione tra contrari, bensì in rapporto di continuità quale costante del discorso performático soggetta a multiformi gradazioni. Quella tra attore e spettatore è una interazione, un dialogo, che non si gioca sulla relazione frontalità/immersività bensì su quella interattività/non-interattività dalla cui articolazione emergono le differenti e cangianti forme teatrali che popolano e popoleranno gli ecosistemi performátici.This research focuses on the modes of production and reception of theatricality in contemporary performative practices with aesthetic purposes. Specifically, the research examines practices which – within performatic ecosystems – plan the action through strategies and devices for the theatricalisation of the event based on co-participatory immersive models, affecting the spectator’s semiocognitive mechanisms of interpretation. The concept of performatic ecosystems enables the pertinentization of the different semiotic formations that emerge from the performative continuum of the semiosphere, grasping the ecological and evolutionary relationships that are established diachronically among theatrical forms. Thereby, transformations are mostly grasped, yielding to semiotic analysis a dynamic image of the performing arts rooted in culture and society, and of the ways in which the basic mechanisms of theatricality shape. With an ethnographic ecological cognitive approach, corporeality and regimes of presence are approached, introducing the concept of emplacement into relational analysis as a supplement to the notion of embodiment. An autopoietic model of enunciation as an act of monstration is formulated through the metaphor of “conversation”. For in the ecology of the performatic environment, an “interactive field” is established between actor and spectator, within which theatrical enunciation is accomplished. Hence, selected case studies illustrate how immersive co-participatory experiences reconfigure the set of norms and habits naturalized in the Western theatrical tradition of drama. Finally, the relationship between frontality and immersivity is conceived not in terms of opposition between contraries, but rather in a relationship of continuity as a constant in performatic discourse undergoing multifarious gradations. The one between actor and spectator is an interaction, a dialogue, not based on the relationship frontality/immersivity but on the articulation of interactivity/non-interactivity whereby the different and mutating theatrical forms that populate and will populate performatic ecosystems emerge