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Percutaneous Cement Discoplasty: Biomechanical and clinical assessment of a minimally invasive treatment of lumbar intervertebral disc disease
Get PDFWith population ageing, spine diseases have an increasing prevalence and induce high economic and social costs. The development of minimally invasive surgeries allows reducing the surgery-associated risks in elderly and polymorbid patients, and save costs by treating more patients in shorter time and reducing the complications. Percutaneous Cement Discoplasty (PCD) is a minimally invasive technique developed to treat highly degenerated intervertebral discs exhibiting a vacuum phenomenon. Filling the disc with bone cement creates a stand-alone spacer which partially restores the disc height and re-opens the foraminal space.
PCD has recently been introduced to clinical use. However, the spine biomechanics following this treatment remained unravelled. The aim of this PhD thesis is to bridge the clinical experience with in vitro methodologies, to provide a multilateral evaluation of PCD outcome and a better understanding of its impact on the spine biomechanics, and of its possible contraindications.
Firstly, a suitable in vitro porcine model to test the biomechanics of discoplasty by comparing specimens in the preoperative and postoperative conditions was developed. The methodology was then applied to investigate the biomechanics of discoplasty in cadaveric human segments. The in vitro specimens were mechanically investigated in flexion and extension, while a DIC system quantified the range of motion, disc height, and strains on the disc surface.
Then, a versatile tool to measure the impact of discoplasty on the foramen space was developed and applied both to clinical and experimental work. The vertebrae reconstructed from CT scans were registered to match the loading configuration, using ex vivo DIC measurements under loading. The foramen volumetric changes caused by PCD was measured using a 3D geometrical method clinically developed by the research group.
In conclusion, this project significantly extended the understanding of PCD biomechanics, highlighting its benefits in the treatment of advanced cases of intervertebral disc degeneration
Children’s socialization, involved parenting, and the construction of the family-school partnership in everyday family interactions: a study on parent-assisted homework as a morally dense educational arena
Get PDFThis study investigates an activity that takes place at the intersection between family and school and plays a key role in the building of the family-school partnership largely promoted by education policies: parent-assisted homework. Even though this topic is not new in pedagogical research, what is innovative about this study is the focus on naturally occurring parent-child conversations during homework. Adopting a phenomenological approach to the study of educational events and relying on conversation analysis, the present study analyzes 62 video-recorded sessions of parent-assisted homework collected in 19 Italian families with children aged 6-10 years old (i.e., attending primary school). The analysis of parent-child interactions reveals that parent-assisted homework is not only a site for formal learning but also and primarily a morally dense educational arena. Through the ‘small talks’ that accompany the completion of homework exercises, parents and children evoke and co-construct moral ideologies concerning topics as diverse as learning, school rules and standards, ‘good, involved parenting’, the family-school partnership, children’s autonomy, virtue, time management, and the organization of knowledge and authority in interaction. By taking part in everyday homework interactions, children are educated to culture-specific ethical systems and socialized into morally competent members of their communities, while parents implement the family-school partnership and comply with the model of “involved parent” proposed by pedagogical research and policies. Providing empirical evidence for the moral and educational relevance of ordinary family talk, this study contributes to pedagogical research on family life and promotes parents’ reflexivity about their mundane interactive activities
Transitional Justice as a Post-Revolution Constitutional Arrangement: A Law and Economics Approach
Get PDFThis dissertation addresses the timely questions of transitional justice (TJ) in the
aftermath of revolutions against autocratic regimes, dealing with TJ as a constitutional
arrangement through the lenses of constitutional economics.
After an introductory chapter, chapter 2 deals with why nations rarely adopt meaningful TJ
processes in the first place, it then explains the limitations of civil society as the arbiter,
facilitator, and enforcer of TJ policies.
Chapter 3 tackles the question of which mechanisms to choose? It uses the UN Guidelines on
TJ that sets five principal TJ mechanisms. It provides a cost-benefit analysis (CBA) of each
mechanism and suggests policy implications accordingly.
The CBA inspires chapter 4 analysis, suggesting a tradeoff between restrictive fair trial
standards under constitutional laws and justice considerations. The tradeoff explains the
suggested efficiency of the balanced TJ approaches that combine trials and amnesties.
This approach is used for the case study analysis of TJ in Tunisia after the 2011 revolution in
chapter 5. The chapter presents the first index of TJ mechanisms in Tunisia through novel data
collected by the author. It shows an ultimate TJ design that ended with a modest harvest in the
application. The lack of cooperation between the Tunisian parties, added to the absence of
transparency in many TJ measures, threatens any possible positive outcomes of the partial TJ
process. It is also alarming regarding constitutional compliance in a system that – until recently
- was considered the only democracy in the Arab region. Chapter 6 is a summar
Novel advance for smart batteries testing and monitoring
Get PDFThe aim of this thesis work is to contribute to the technological advancementof energy storage systems, especially batteries, in terms of efficiency and safety.
The thesis to be demonstrated argues that on the one hand, the possibility of testing electrode materials with a more performing and versatile system than those present in the state of the art allows to reach a level of characterization
and understanding of the working behaviour of these materials higher than the current state. On the other hand, the use of economic and at the same time effective sensors makes it possible to improve the production process of electrochemical cells and to monitor their state of health during their useful life, ultimately achieving the desired high level of reliability.
The main activity of this work consists of three different experimental phases aimed at improving the performance of an instrument for testing the electrodes in rechargeable batteries, as well as the search for an economic and
high-performance sensor to detect electrolyte losses in the production process of lithium-ion batteries and the study of an innovative sensor that can be integrated into the electrochemical cell that can closely monitor its stability by intercepting any malfunctions
L'identità nazionale degli Stati membri nel diritto dell'Unione Europea
Get PDFLa identidad nacional es una categoría jurídica central del Derecho de la Unión que puede ser particularmente apta a los fines de articular un mejor encaje entre los ordenamientos jurídicos nacionales y el sistema jurídico europeo. Se enmarca en un debate clásico de la construcción europea relativo a cómo conciliar una integración cada vez más acentuada con el debido respeto a la diversidad estatal. Se caracteriza por tratarse de una figura jurídica sumamente controvertida, existiendo una rica y abierta discusión en relación a su sentido y a su alcance. Con la entrada en vigor del Tratado de Lisboa en el año 2009, la nueva redacción de la cláusula de identidad nacional ha suscitado un interés renovado tanto por parte de la doctrina como de la jurisprudencia nacional y europea gracias a su mayor elaboración y a la ampliación de las potestades de la jurisdicción supranacional. La presente tesis doctoral ofrece un análisis integral de esta norma desde una aproximación dialéctica, que comprende tanto la visión acuñada por el Tribunal de Justicia como la percepción que de la misma mantienen los Tribunales Constitucionales nacionales, en tanto que guardianes supremos del ordenamiento constitucionales interno. Cada uno de los cuales sostiene una visión no exactamente coincidente sobre la norma suprema y la autoridad judicial última en el complejo sistema constitucional común europeo. Se lleva a cabo un estudio desde una perspectiva histórica y actual, sustantiva y procesal, descriptiva y valorativa, así como una parte propositiva por medio de la cual se propone un modelo para la resolución de este tipo de conflictos en sede judicial.National identity is a central legal category in EU law that may be particularly suitable for the purpose of better linking national legal systems with the European legal system. It is part of a classic debate in European integration concerning how to reconcile increasing integration with due respect for national diversity. It is characterised by the fact that it is a highly controversial legal concept, and there is a rich and open debate on its meaning and scope. With the entry into force of the Lisbon Treaty in 2009, the new wording of the national identity clause has aroused renewed interest both in doctrine and in national and European case law thanks to its further elaboration and the extension of the powers of supranational jurisdiction. This doctoral thesis offers a comprehensive analysis of this rule from a dialectical approach, which includes both the vision coined by the Court of Justice and the perception of it held by the national Constitutional Courts, as supreme guardians of the internal constitutional order. Each of them holds a not exactly coinciding view of the supreme rule and the ultimate judicial authority in the complex common European constitutional system. A study is carried out from a historical and current, substantive and procedural, descriptive and evaluative perspective, as well as a propositional part by means of which a model for the resolution of this type of conflict in the courts is proposed.L'identità nazionale è una categoria giuridica centrale del diritto dell'Unione che può essere particolarmente adatta allo scopo di articolare un migliore adattamento tra i sistemi giuridici nazionali e il sistema giuridico europeo. Fa parte di un classico dibattito sull'integrazione europea che riguarda come conciliare la crescente integrazione con il dovuto rispetto per la diversità nazionale. È caratterizzato dal fatto che è una figura giuridica estremamente controversa, e c'è una discussione ricca e aperta riguardo al suo significato e alla sua portata. Con l'entrata in vigore del Trattato di Lisbona nel 2009, la nuova formulazione della clausola di identità nazionale ha suscitato un rinnovato interesse sia nella dottrina che nella giurisprudenza nazionale ed europea grazie alla sua ulteriore elaborazione e all'estensione dei poteri della giurisdizione sovranazionale. Questa tesi di dottorato offre un'analisi integrale di questa norma a partire da un approccio dialettico, che include sia la visione coniata dalla Corte di Giustizia sia la percezione che ne hanno le Corti Costituzionali nazionali, come supremi guardiani dell'ordine costituzionale interno. Ognuno di loro ha una visione non esattamente coincidente della regola suprema e dell'autorità giudiziaria ultima nel complesso sistema costituzionale comune europeo. Si realizza uno studio da una prospettiva storica e attuale, sostanziale e procedurale, descrittiva e valutativa, così come una parte propositiva attraverso la quale si propone un modello per la risoluzione di questo tipo di conflitto nei tribunali
Effects of Adapted Physical Activity on Quality of Life, Physical Fitness and Fear of Falling in People with Osteoporosis
Get PDFUndertaking regular physical activity is one of the major determinants of health. Indeed, Physical Activity (PA), when adapted and in the right dosage, can be considered a protection and even a therapy for some chronic diseases, including Osteoporosis (OP). Clinical and social OP implications are mainly due to osteoporotic fractures that reach 1/3 of menopausal women. Among OP fractures, vertebral ones are associated with a significant decline in Quality of Life (QoL) and disability. Therefore, OP and associated fractures constitute a major public health concern. In literature, no definitive conclusions are available regarding benefits of PA for individuals with OP and vertebral fractures. Furthermore, it is unclear which exercise is optimal for these patients. Lastly, there is no specific indication on the best setting in which to exercise in. For these reasons, this present thesis aims to increase the knowledge on the type of exercise and training adapted for people with OP and its relative effects on QoL, physical fitness and fear of falling. Moreover, effects of exercise on bone biomarkers are investigated to deepen the topic. Findings from these studies can admittedly contribute in providing information on the beneficial effects of Adapted Physical Activity (APA) programs and also identifying the type of safe exercise to prescribe for the osteoporotic population. Moreover, the role of these studies lies in defining possible future strategies to be applied by the involvement of health policy-makers, in order to primarily improve QoL in women with OP. Therefore, these indications are also intended to encourage the healthcare world to refer osteoporotic people to follow a healthy lifestyle, including APA programs regularly administered by trainers able to deal with these conditions, especially for the prevention of fractures which represent the first cause of decline in terms of QoL, physical fitness and fear of falling
Antonio Canova and the British: sources, patronage and cultural exchanges
Get PDFIl rapporto di Antonio Canova con la società e la cultura inglese è da sempre considerato di fondamentale importanza, ma solo negli ultimi anni è stato oggetto di studi più approfonditi, tuttavia per lo più limitati alle vicende della committenza artistica: una riflessione che ambisse a tenere insieme le fila delle molteplici sfaccettature del tema ricostruendo ed interconnettendo tra loro gli aspetti alla base di questa relazione di mutuo arricchimento mancava ancora nella pur ricchissima bibliografia canoviana. Per poter intraprendere una simile indagine, si è preso le mosse dalla quanto mai corposa documentazione archivistica e dalle molte fonti a stampa dell'epoca, integralmente trascritte nelle quattro appendici a corredo di questo studio. Se ne sono tratti un piccolo dizionario biografico di tutte le personalità britanniche in rapporto con l'artista nell'arco della sua intera carriera ed un catalogo di oltre sessanta opere in vario modo legate alla committenza ed al collezionismo inglese. Nel saggio, invece, la disamina del tema in oggetto è stata condotta affrontandone in ciascun capitolo singoli aspetti distintivi: la committenza e la mutua influenza culturale; le relazioni politiche e diplomatiche intercorse tra Canova ed il Regno Unito attraverso la sua arte; lo straordinario favore goduto dallo scultore in terra inglese e le ragioni profonde della sua precoce sforuna critica; infine il suo rapporto con le arti figurative e letterarie britanniche, un ambito di ricerca complesso e relativamente originale per il quale si è avviata un'indagine introduttiva utile, si spera, ad impostare la ricerca per futuri approfondimenti. L'obiettivo perseguito, pertanto, è quello di gettare uno sguardo finalmente generale su di un fenomeno che, osservato nella sua interezza, può ancora spiegare moltissimo sulla figura e la carriera di Antonio Canova, personalità che appare, oggi più che mai, di statura europea.The relationship between Antonio Canova and the British culture and society has been always judged of primary importance, but only in recent times a new interest in it has increased among scholars, producing some important essays and publications. Notwithstanding, the very rich bibliography on Antonio Canova still lacks a general reflection on such a phenomenon, a study which aims to keep in dialogue all different aspects of the matter. To engage in a research like this one, I consulted both the archival documentation, so great in number, and many edited sources of that time, all of them totally transcribed in the four appendices at the end of the thesis. Such a material permitted me to draft a little biographical dictionary of almost all the British people with whom Canova kept in touch during his entire life and a general catalogue of about 60 works of arts related to British patronage. The essay, divided in four chapters, analyses and reflects on four different aspects of the complex relationship between the sculptor and his english-speaking friends: the artistic patronage for private collectionism; the political and diplomatical role of Canova; the critical reception of his works of art in the United Kingdom before and after his death; his influence on British art and literature and vice versa. In conclusion, the final aim is to have a general, not particular look on that aspect of Canova's career which can be considered one of the most important for the developement of his art and international fame
The human gut microbiome in disease: Role in chemotherapy treatments and relationship with clinical outcomes
Get PDFThe gut microbiome (GM) is a plastic entity, capable of adapting in response to intrinsic and extrinsic factors. However, several circumstances can disrupt this homeostatic balance, forcing the GM to shift from a health-associated mutualistic configuration to a disease-associated profile. Nowadays, a new frontier of microbiome research is understanding the GM role in chemo-immunotherapies and clinical outcomes. Here, the role of the genotoxin‐producing pathogen Salmonella in colorectal carcinogenesis was characterized by in-vitro models. A synergistic effect of Salmonella and the CRC-associated mutation (APC gene) promoted a tumorigenic microenvironment by increasing cellular genomic instability. Subsequently, the GM involvement in anti-cancer therapies was investigated via next-generation sequencing in different patient cohorts. The GM trajectory during treatments was characterized for women with epithelial ovarian cancer and pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). The results highlighted the loss of GM homeostasis, with diversity reduction, decrease in health-associated microorganisms and pathobiont bloom. Interestingly, a distinctive GM profile was identified in ovarian cancer patients with a poor response to chemotherapy compared to patients in remission. Moreover, maintenance of GM homeostasis through enteral feeding in pediatric HSCT patients highlighted a better prognosis, with reduced risk of clinical complications. In this context, the gut resistome – the pattern of GM antibiotic-resistance genes (ARGs) – was evaluated longitudinally in HSCT patients. The results showed new acquisitions and consolidation of ARGs already present in patients developing clinical complications. Antibiotic exposure was also evaluated in infants under low-dose antibiotic prophylaxis for vesico-ureteral reflux showing an impairment of the GM configuration with possible long-term health implications. Dramatic GM dysbiosis was finally observed in critically ill patients with COVID-19 (undergoing multiple drug therapies) and correlated with increased risk of bloodstream infection. All these findings pointed out the importance of maintaining GM homeostasis during chemotherapy treatments for improving patients’ clinical outcomes
Test bench development, experimental analysis and modelling of micro-organic Rankine cycle for low-grade heat recovery
Get PDFThis thesis presents the detailed experimental and numerical analysis conducted on a prototype of micro-scale organic Rankine cycle (ORC) power system. The system is conceived for stationary co-generative applications in the residential sector, since it is characterized by a power output in the kW-scale. Suitable heat sources are low-enthalpy geothermal energy, biomass combustion, solar thermal collectors or low-temperature waste heat recovery. The system is driven by a reciprocating piston expander prototype, and uses HFC-134a as working fluid, hence it is suitable for temperature of heat source in the range 60-90 °C. The micro-ORC has been tested in a wide range of operating conditions, with the aim of deeply characterizing the system behavior and understanding the effect of each process variable on the performance of the power plant. The main objectives of this thesis are:
- presenting the characteristics and performance of the prototypal micro-ORC system
- assessing the dependencies of the micro-ORC system steady-state performance from the off-design operating conditions, by analyzing the behavior of each component;
- estimating experimentally the system response to transient variations of the operating conditions, in order to deduce guidelines for the control system design;
- developing and validating a charge-sensitive thermodynamic model to simulate the ORC system in stationary and dynamic conditions.
The analysis here presented aims at providing a contribution to the research field of micro-scale and low-temperature organic Rankine cycles, especially from the experimental point of view. The improvement of micro-ORC performance and reliability is one of the key factor for the market spread of this technology, helping to enhance the global electricity generation efficiency, save primary resources and greenhouse gases emissions, and increase the exploitation of renewable thermal sources
The Role of B5G UAV-Aided Mobile Networks
Get PDFWith the advent of 5G, several novel network paradigms and technologies have been proposed to fulfil the key requirements imposed. Flexibility, efficiency and scalability, along with sustainability and convenience for expenditure have to be addressed in targeting these brand new needs. Among novel paradigms introduced in the scientific literature in recent years, a constant and increasing interest lies in the use of unmanned aerial vehicles (UAVs) as network nodes supporting the legacy terrestrial network for service provision. Their inherent features of moving nodes make them able to be deployed on-demand in real-time. Which, in practical terms, means having them acting as a base station (BS) when and where there is the highest need.
This thesis investigates then the potential role of UAV-aided mobile radio networks, in order to validate the concept of adding an aerial network component and assess the system performance, from early to later stages of its deployment. This study is intended for 5G and beyond systems, to allow time for the technology to mature.
Since advantages can be manyfold, the aerial network component is considered at the network layer under several aspects, from connectivity to radio resource management. A particular emphasis is given to trajectory design, because of the efficiency and flexibility it potentially adds to the infrastructure. Two different frameworks have been proposed, to take into account both a re-adaptable heuristic and an optimal solution. Moreover, diverse use cases are taken under analysis, from mobile broadband to machine and vehicular communications.
The thesis aim is thus to discuss the potential and advantages of UAV-aided systems from a broad perspective. Results demonstrate that the technology has good prospects for diverse scenarios with a few arrangements