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Analytical methods for modeling elastic metasurfaces
No full textThis dissertation aims at developing advanced analytical tools able to model surface waves propagating in elastic metasurfaces. In particular, four different objectives are defined and pursued throughout this work to enrich the description of the metasurface dynamics.
First, a theoretical framework is developed to describe the dispersion properties of a seismic metasurface composed of discrete resonators placed on a porous medium considering part of it fully saturated. Such a model combines classical elasticity theory, Biot’s poroelasticity and an effective medium approach to describe the metasurface dynamics and its coupling with the poroelastic substrate. Second, an exact formulation based on the multiple scattering theory is developed to extend the two-dimensional classical Lamb’s problem to the case of an elastic half-space coupled to an arbitrary number of discrete surface resonators. To this purpose, the incident wavefield generated by a harmonic source and the scattered field generated by each resonator are calculated. The substrate wavefield is then obtained as solutions of the coupled problem due to the interference of the incident field and the multiple scattered fields of the oscillators. Third, the above discussed formulation is extended to three-dimensional contexts. The purpose here is to investigate the dynamic behavior and the topological properties of quasiperiodic elastic metasurfaces. Finally, the multiple scattering formulation is extended to model flexural metasurfaces, i.e., an array of thin plates. To this end, the resonant plates are modeled by means of their equivalent impedance, derived by exploiting the Kirchhoff plate theory. The proposed formulation permits the treatment of a general flexural metasurface, with no limitation on the number of plates and the configuration taken into account. Overall, the proposed analytical tools could pave the way for a better understanding of metasurface dynamics and their implementation in engineered devices
Pellegrino Prisciani's encyclopaedism between new sources and critical tradition
No full textIl presente elaborato verte sulla figura di intellettuale dell’umanista Pellegrino Prisciani (1435ca-1518), il primo tomo, prova a ridiscutere alla luce della sua esperienza culturale la biografia, tra letteratura ed impegno politico. Chiude il tomo una lunga e articolata appendice di tutte le lettere da e per il ferrarese, che riguardano l’intera parabola di vita. Il secondo tomo prende in esame i due manoscritti miscellanei a questi attribuiti: nel primo capitolo se ne discute autorialità, datazione e contenuti, nel secondo si riflette sulla partecipazione di Pellegrino al revival antiquario del XV secolo, testimoniata tanto dalla presenza di trascrizioni di epigrafi quanto dall’uso di scritture all’antica, come le maiuscole epigrafiche. Il secondo tomo si conclude con le trascrizioni semi-integrali dei due manoscritti.This thesis reflects on the intellectual and biographical parabola of the humanist Pellegrino Prisciani (1435ca-1518) while the first book tries to re-image the life of the author availing the use of documents, like letters (that occupy the second part of the first volume), the second volume analyses two multiple-texts codices related to him, especially for those matters: authorship, dating, and contents; the second part of the book tries to focus Pellegrino’s experience as an antiquarian both because he transcribed epigraphies and experienced new writings, influenced by the paduan antiquarian environment. In the end, a partial transcription of the manuscripts is provided
Impact of functional rehabilitation for erectile function recovery of prostate cancer patients underwent robotic radical prostatectomy with nerve-sparing approach from a bio-psycho-social perspective
Get PDFIntroduction: Prostate cancer is the most common malignancy among men, often detected at a localized stage in younger, healthier patients. Although robot-assisted radical prostatectomy (RARP) with nerve-sparing (NS) techniques aims to optimize recovery of erectile function (EF), outcomes remain variable, impacting quality of life. Rehabilitation rotocols combining pharmacologic and psychosexual interventions may enhance EF recovery. Materials and Methods: This retrospective cohort study included 640 patients who underwent RARP with NS techniques from 2020 to 2024. Patients with severe pre-existing rectile dysfunction (IIEF-5 score <17) or short follow-up (<24 months) were excluded. Surgical approaches were stratified into categories (bilateral intrafascial, bilateral nterfascial, interfascial/extrafascial) based on nerve preservation. Postoperative rehabilitation involved adalafil (20 mg, thrice weekly), vacuum erection devices (VED), intracavernosal injections (ICI), and optional psychosexual counseling for relational health assessment (Dyadic Adjustment Scale, PCS-12, MCS-12). EF recovery was measured using IIEF-5 scores at intervals over 24 months. Multimodal logistic estimates, Kaplan Meier curves and Cox’s promotional hazard models were used to investigate the functional recovery. Results: At 12 months, patients with bilateral intrafascial NS and combined PDE5i + VED therapy showed the highest EF recovery, particularly in younger patients (<65 years), with median IIEF-5 scores significantly improved. Psychosexual counseling positively correlated with relational and EF
recovery. Kaplan-Meier curves demonstrated quicker EF recovery for younger patients and those with bilateral NS, with 86% achieving baseline EF by 24 months.
Conclusions: Robot-assisted RARP, combined with structured PDE5i + VED therapy, significantly enhances EF recovery, particularly for younger individuals with bilateral intrafascial NS. Psychosexual support further aids recovery, highlighting the importance of a biopsychosocial approach in post-RARP rehabilitation. Future multicenter studies are recommended to standardize penile rehabilitation protocols
Design and synthesis of RAD51/RAD52 inhibitors to achieve synthetic lethality in combination with PARP inhibitors in pancreatic cancer
Get PDFMy main PhD research project focused on the discovery of potential disruptors of the RAD51-BRCA2 protein-protein interaction, with the goal of triggering synthetic lethality in BRCA2-proficient pancreatic cancer, in combination with PARPi. SL has been clinically validated as a therapeutic approach for cancer due to the efficacy of olaparib in BRCA2-deficient patients. In this scenario, we suggested to trigger a “fully small-molecule-induced SL” by combining a RAD51-BRCA2 PPI disruptor with PARPi to target pancreatic cancer cells. The interaction between RAD51 and BRCA2 is crucial in DNA damage repair by homologous recombination and is mediated by two key “hotspots” on RAD51 surface, identified as Zone I and Zone II, which have been previously confirmed as ideal sites to design small molecule inhibitors.
Initially, a virtual screening campaign on Zone II was exploited as hit identification strategy, followed by chemical modifications that led to the creation of a library of analogues. Derivative 14 proved to be a promising lead compound inhibiting RAD51-BRCA2 interaction, reducing HR and inducing cell death in combination with olaparib in BRCA2-proficient pancreatic cancer cell lines, fully reproducing the paradigm of SL.
The second part of the thesis concerned the experience I carried out during the six-month secondment at EPFL in Lausanne in Professor Heinis' Laboratory. The project focused on the synthesis of dipeptides aimed at inhibiting the monomer-monomer interaction of RAD52. RAD52 inhibition proved to induce SL in cancer cells with defective DNA repair-related proteins, such as BRCA1/2 proteins. After a VS on an identified RAD52 monomer-monomer interaction pocket, the best 10 dipeptides had been synthesized. Preliminary biophysical assays have been carried out to evaluate their efficacy in binding RAD52. The final goal will be triggering a three-pathways SL by a PARPi, a RAD51-BRCA2 PPI disruptor and a potential RAD52i in BRCA2-proficient pancreatic cancer cells
Ethnobotanical, metabolomic and bioactivity study of Italian alimurgic plant species traditionally used in folk medicine
No full textTraditional medicine is the oldest form of health care, used to prevent/treat human illnesses, born by the experiences of different cultures, orally transmitted until today.
The aim of this work was to analyse alimurgic plants used in Italian folk medicine, to acquire preliminary scientific data to link their traditionally reported effectiveness in treating human diseases.
B.officinalis, C.dactylon, F.vulgare, H.perforatum, M.sylvestris, S.nigra, U.dioica were collected in three Italian regions. Polyphenols, reducing sugars, proteins and antioxidant activity were quantified with spectrophotometric techniques and resulted to be higher in flowers and leaves respect to stems and roots.
Next, B.officinalis, F.vulgare, H.perforatum and S.nigra infusions and decoctions were subjected to an in vitro simulated digestion, to verify how plant metabolites and their biological activities are affected by human digestion. Phenols and antioxidant activity decreased after digestion, while reducing sugars and proteins increased.
H.perforatum phenolic profile was analysed with HPLC-DAD and resulted to be composed by rutin, epicatechin, epigallocatechin, catechin and caffeic acid. H.perforatum and B.officinalis extracts were chemically characterized with NMR, resulting three main classes of molecules, aliphatic, proteins, aromatic compounds.
The preparations efficacy in external treatments against skin diseases was finally tested.
Infusions/decoctions showed anti-tyrosinase activity (probably due to phenolics in not digested and bioactive peptides in digestates); not digested showed antimicrobial activity (they could be effective for topical applications) and anti-inflammatory activity and did not exert any toxicity (potential hormetic effect).
The analysed alimurgic species preparations showed high concentrations of phytochemicals and demonstrated to have significant biological activities: not digested showed evidences linked to their traditional topical uses, and digestates mimicking the traditional use through oral ingestion. Many other variables acting in the human organism could not be replicated in laboratory during the present thesis work, so further analyses are needed to justify the folk medicinal uses of these plant preparations
Data driven modelling of permafrost induced geomorphological hazard
No full textMy thesis dives into a relevant scientific problem which involves two aspects.
The first corresponds to the need to employ data-driven solutions to cryospheric hazards in high-latitude landscapes.
This is due to the limited data historically collected across such landscapes and it links to the second aspect: a contribution in the form of mapping and sharing results with the whole community.
In fact, I have been involved in mapping cryospheric processes such as thaw slumps (TS), retrogressive thaw slumps (RTS), active layer detachments (ALD), and thermo-erosion gullies (TEG), and developing susceptibility models for each one of them and their potential combination.
As a sub-theme to my research, I have also explored whether immovable infrastructure such as cultural heritage sites may be subjected to any of the processes mentioned above.
In fact, if that is the case, the memories and value associated to such heritage may be lost, especially because climate projections are expected to further promote permafrost degradation across the whole Arctic and peri-Arctic regions.
The thesis is divided into three main components, each corresponding to one of the main experiments I have carried out.
In terms of study areas, I have addressed analogous problems and research applications in Alaskan and Norwegian areas
Double-row suture-bridge technique does not yield better clinical and radiological results than single-row technique in patients older than 55 years at 2 years minimum follow-up: a comparative study
Get PDFLe tecniche di riparazione artroscopica della cuffia dei rotatori sono in continua evoluzione e negli ultimi anni, le tecniche basate sull’utilizzo di ancorette di sutura come il Single-row (SR) e il Double-row Suture-bridge (DRSB) stanno sempre più guadagnando popolarità e rappresentano attualmente un argomento molto dibattuto in letteratura.
Nonostante la continua evoluzione dei materiali, sono ancora alti i tassi di fallimento precoce in seguito a riparazione artroscopica della cuffia dei rotatori
Questo studio monocentrico retrospettivo è volto a valutare l’outcome clinico-radiografico in pazienti trattati con tecnica di riparazione della cuffia dei rotatori utilizzando tecnica SR o DRSB in seguito a lesione a tutto spessore.
Cinquanta pazienti con lesioni della cuffia dei rotatori sono stati sottoposti a riparazione utilizzando tecnica SR o DRSB. La valutazione includeva score clinici specifici ,test di forza e valutazione dell’integrità del tendine pre e post operatoriamente tramite Risonanza Magnetica Nucleare (RMN) a 3 Tesla.
Entrambi i gruppi hanno mostrato risultati clinici, di forza e radiologici sovrapponibili al follow-up minimo di 24 mesi. Non è stata trovata alcuna correlazione significativa tra la tecnica di riparazione utilizzata e i risultati clinici o i tassi di nuova rottura.In pazienti con grading preoperatorio secondo Patte e Goutallier >1 sono stati riscontrati punteggi Constant-Murley postoperatori inferiori.
Questo studio dimostra che le tecniche SR e DRSB offrono risultati clinici e tassi di guarigione del tendine sovrapponibili quando utilizzati per riparare lesioni della cuffia dei rotatori in pazienti di età superiore a 55 anni a un follow-up minimo di 24 mesi.Background: Arthroscopic rotator cuff repair (RCR) has evolved, with suture anchor-based techniques like Single-row (SR) and Double-row Suture-bridge (DRSB) gaining popularity. Despite improvements, early repair failures remain concerning, necessitating continued assessment of repair methods and devices' lasting impact. This study compares DRSB versus SR repairs at 24 months minimum follow-up, hypothesizing superior clinical outcomes and improved tendon healing with DRSB techniques.
Methods: Fifty patients with rotator cuff tears underwent either SR or DRSB repairs. Clinical evaluation included standardized scoring systems and strength testing. Magnetic Resonance Imaging (MRI) assessed tendon integrity. Partial cuff tears were evaluated according to Snyder’s Southern California Orthopaedic Institute rotator cuff classification system, which classifies <2 cm lesions as C2 in its scoring system.
Results: Both groups showed comparable clinical outcomes, strength, and MRI findings at 24 months minimum follow-up. No significant correlation was found between repair technique and clinical outcomes or retear rates. Preoperative Patte and Goutallier grades >1 were associated with lower postoperative Constant-Murley scores.
Conclusion: This study suggests that both SR and DRSB techniques offer comparable clinical outcomes and tendon healing rates for rotator cuff tears in patients over 55 at 24 months minimum follow-up. While limitations exist, our findings contribute to understanding optimal surgical approaches, emphasizing individualized treatment based on patient characteristics and surgeon expertise. Further research, including randomized controlled trials with long-term follow-up, is needed to refine treatment algorithms and improve patient outcomes in rotator cuff surgery
Nonlinear modelling of radiofrequency devices for reconfigurable and sensing applications
Get PDFRadiofrequency (RF) technologies have tremendously evolved in a bid to answer the ever-increasing demand for flexibility and efficiency of communication systems. In that respect, reconfigurability within a system plays the key role of dynamic adjustment to changing operation conditions: frequency bands, modulation schemes, and power levels. Reconfigurable RF systems are going to be fundamental in handling the challenges thrown up by modern communication networks, which include increasing data rate while improving spectrum efficiency and reducing energy consumption. Among the advanced materials that promise to provide RF reconfigurability are ferroelectric materials. In particular, a focus on the nonlinear modeling of Hafnium-Zirconium-Oxide-based (HfZrO) devices is presented, with particular attention to passive phase shifters. Moreover, the integration of HfZrO with complementary metal-oxide-semiconductor (CMOS) technology opens up a new generation of reconfigurable RF circuits. In this context, a new silicon-integrated technology for antenna realization and their derivative applications, such as RF Energy Harvesting (EH), is presented, focusing on the design and implementation of different rectennas operating at multiple frequencies. The topic of EH is also discussed in the framework of the design and realization of a novel topology for a wide dynamic range of applications. The need for stand-alone RF systems and circuits is of particular interest to microwave sensing applications. In particular, a focus on biological microwave sensing is presented. Two distinct solutions, for wood moisture content monitoring and skin hydration, are reported. Particular attention is given to a new sensing strategy that avoids the need for external instrumentation by only monitoring the steady-state regime of nonlinear circuits. Finally, a description of the activities carried out in joint projects with industry is reported, mainly focusing on the design of a novel positioning system for railway transport systems based on Long Range (LoRa) protocol and of a three-antenna system
Improving renewables integration in distribution networks through real-time inertia estimation and optimal management of energy community resources
Get PDFThe thesis explores two critical aspects of renewable energy sources (RES) integration in power systems: inertia estimation in systems with many Converter-Interfaced Sources (CISs) from RES and the management of the controllable resources of Renewable Energy Communities (RECs). Unlike traditional rotating generators, CISs lack physical inertia, requiring advanced Primary Frequency Control (PFC) approaches. A two-stage online inertia estimation method is proposed, combining optimization-based PFC parameter identification with regression-based inertia estimation.
RECs are a recent means introduced in Europe to promote energy production by RES and local self-consumption. A comprehensive review of the European Union’s REC regulatory framework highlights national implementation diversities, including proximity constraints, rated power limitations, and energy-sharing methods. An Energy Management System (EMS) is proposed, integrating smart meter data collection, energy price acquisition, and a rolling-horizon optimization procedure to minimize energy procurement costs. The EMS incorporates load and Photovoltaic (PV) production forecast and can be suitably adapted to account for the above-mentioned diversities. Within this context, incentive-based and four-price market models are introduced for cost minimization, compliant with national REC regulations. The impact of new asset installations, such as PV systems and Battery Energy Storage (BES), is assessed using standard load profiles obtained from measurement campaigns.
The research aimed at contributing valuable insights into the advancing landscape of power systems with substantial RES integration. In this respect, the two-stage online inertia estimation process has been proved to provide accurate inertia values by using an OPAL-RT real-time simulator and the IEEE 39-bus network model, under diverse operational scenarios including CISs presence. Finally, the proposed EMS provides practical solutions to challenges in RES management, with the EMS's adaptability to regulatory changes enhancing its potential for broader deployment in ancillary services markets
Distributed optimization strategies and toolboxes for cooperative multi-robot systems
Get PDFThe widespread adoption of multi-robot systems in areas such as farming, smart warehouses, cooperative exploration, and environmental monitoring highlights their potential to enhance efficiency, scalability, and adaptability in real-world applications. However, integrating intelligent cooperative strategies and transitioning from numerical simulations to experimental deployment are significant opened challenges towards the alignment of academic advances with the modern industrial objectives. This thesis addresses the above challenges by developing novel distributed control and optimization strategies for multi-robot systems that are ready for deployment. These strategies are integrated with distributed computing paradigms and virtualization tools, thus enabling multi-robot systems to accomplish complex tasks. We start by developing a multi-robot software platform that supports the implementation of distributed algorithms by leveraging a high-fidelity simulation engine for mixed-reality deployments. These toolboxes also include software-containerization mechanisms for distributed computing. Subsequently, we propose novel distributed optimization strategies by leveraging the aggregative optimization framework to accomplish cooperative tasks. In this approach, we address challenges related to realistic communication over a sparse network, robot heterogeneity, safety, and scalability. Finally, these strategies are validated through several case studies, including cooperative surveillance scenarios, target encirclement and underwater surveillance. In each scenario, we first validate the proposed algorithms in virtual experiment and then deploy them on real robots, including mixed-reality setups. Through these contributions, this thesis provides a comprehensive set of solutions that integrates novel distributed optimization techniques with distributed computing and virtualization tools, thus enabling the deployment of multi-robot systems in practical applications