IRIS Università degli Studi dell'Aquila
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Developing sustainable strategies for the construction of heterocycles and cyano-functionalization
Get PDFThis thesis presents the development of novel synthetic methods for the preparation
of various nitrogen-containing heterocycles and polyheterocycles, utilizing greener
and more sustainable methodologies. It also explores new electrochemical
cyanation protocols that employ safer cyanide sources and/or milder reaction
conditions.
The Introduction emphasizes the significance of heterocyclic compounds in
everyday chemistry, briefly discussing their applications in pharmaceuticals and
industry.
Chapter 1 introduces the isoindolinone core and its biological properties. The
importance of cascade procedures in the synthesis of isoindolinone derivatives is
also highlighted, with a particular focus on electrochemical methods. The chapter
first details an electro-induced cascade reaction for synthesizing 3-N-aryl
substituted isoindolinones using catalytic amounts of current and supporting
electrolyte. The method was then extended to synthesize isoindolinone-containing
polyheterocycles exploiting the second reactivity of suitable electrophilic moieties
at the ortho-position of the reagents. Finally, the chapter concludes by describing a
one-pot cascade protocol for preparing a C-10-substituted batracylin analog using
Cs2CO3, as the solely catalyst. A preliminary photophysical characterization of the
attained analog is also reported.
Chapter 2 discusses the importance of nitrile group in organic chemistry, outlining
the limitations of traditional cyanation protocols and the consequent need for safer
cyanide sources and greener methods. Two novel electrochemical cyanation
reactions are described: the cyanation of chalcones and imines through the catalytic
electrochemical activation of acetone cyanohydrin, as cyanating agent; the
exploration of the 5-aminotetrazole as a novel and safer CN surrogate, capable of
generating both electrophilic and nucleophilic cyanide for the cyanation of a large
range of substrates. This latter method was also optimized in flow-electrochemical
systems.
Chapter 3 explores the advantages of combining of the Pictet-Spengler and Ugi four
component reactions for the first synthesis of 4-imidazolidinone-tetrahydro-β
carboline hybrids by means of TMSOTf as an effective mediator
Evaluation of Identification Methods for Joints with Inaccessible Interfaces Using Frequency-Based Substructuring
No full textRecently, there has been significant interest in mechanical joint identification through dual substructure decoupling. In this method, each component of a complex mechanical system is handled as an independent substructure. The joint is then identified by subtracting the measured dynamics of the connected subsystems from those of the assembled system. A major challenge with this approach is the need to measure both translational and rotational Frequency Response Functions (FRFs) at the interface between subsystems (interface DoFs). This is often impractical due to the limited space available to place instrumentation. To address this challenge, several techniques available in the literature can be used to derive FRFs at the interface between components using the available measurements. This paper presents a comparative study of three joint identification methods that use two state-of-the-art techniques for obtaining the interface FRFs required for the decoupling process, based on available measurements: Virtual Point Transformation (VPT) and System Equivalent Model Mixing (SEMM). In particular, the advantages and disadvantages of the three methods that combine decoupling with VPT, SEMM, or both, are discussed. Special attention is given to the error propagation associated with each technique. The study is conducted using experimental data from a laboratory benchmark. The results show that the direct VPT approach and the one combining SEMM with VPT give similar results, suggesting that the SEMM is able to accurately reconstruct the FRFs at the boundary DoFs
Berberine bridge enzyme-like oxidases orchestrate homeostasis and signaling of oligogalacturonides in defense and upon mechanical damage
Get PDFThe Stochastic Compressible Navier-Stokes-Korteweg system: The one-dimensional case
Get PDFThe thesis concerns the mathematical theory of the Navier-Stokes-Korteweg equations for capillary fluids. More precisely, we focus on the study of local and global well-posedness problems for the one-dimensional stochastic Quantum-Navier-Stokes equations, which fall into the class of the Navier-Stokes-Korteweg equations, driven by random initial data and stochastic forcing term. The main results achieved in the thesis concern the local and global existence of strong and weak solutions of the one-dimensional stochastic Quantum-Navier-Stokes equations with degenerate viscosity μ(ρ) = ρ^α. In particular we first prove a local well-posedness result for all the values of the viscosity parameter α ≥ 0 in the class of strong pathwise solutions which are strong solutions in both PDEs and probability sense. The proof is based on a multi-layer approximation technique and a stochastic compactness argument. After having established the local well-posedness, we then explore the possibility to extend the solution from a local to a global one. The continuity argument relies on the control of the vacuum regions. This is achieved in the range of the viscosity exponent α ∈ [0, 1/2 ], and thus in this case we prove the global well-posedness of the solutions. Furthermore, in the range 1/2 < α ≤ 1, we prove the existence of global weak dissipative martingale solutions for the one-dimensional stochastic Quantum-Navier-Stokes equations. These solutions are weak in both PDEs and probability sense and may have vacuum regions. The proof relies on the construction of an approximating system which provides extra dissipation properties and admits more regular solutions. The convergence is based on an appropriate truncation of the velocity field in the momentum equation and a stochastic compactness argument. As a byproduct of our analysis, the results hold also in the deterministic setting that is without stochastic forcing term. The thesis also contains an introduction to the derivation of the Navier-Stokes-Korteweg equations in the barotropic regime, a discussion on the choice of the viscosity coefficients, and a detailed description of the stochastic tools used in our analysis
THE USE OF HYPNOSIS IN DENTISTRY IN ANXIOUS PATIENTS. SYSTEMATIC REVIEW OF THE LITERATURE OF THE LAST 5 YEARS
Get PDFBackground:Dental anxiety and odontophobia significantly impact patient care and oral health. These conditions stem from factors such as direct conditioning, vicarious learning, and psychological predispositions, often leading to somatic symptoms and severe avoidance behaviors. Hypnosis has emerged as an effective approach for managing dental anxiety, providing benefits such as reduced fear and pain perception, improved patient collaboration, and enhanced healing.. Materials and Methods:This systematic review followed PRISMA guidelines and analyzed studies retrieved from PubMed, Scopus, and Cochrane databases between 2019 and 2024. Randomized controlled trials, cross-sectional studies, and comparative analyses examining hypnosis for dental anxiety and phobia were included. The Newcastle-Ottawa Scale assessed study quality and risk of bias. Data extraction focused on study design, outcomes, and patient demographics.. Results:The search identified 75 papers, of which 56 were screened after removing duplicates. Following inclusion criteria, eight studies were analyzed. The risk of bias varied, with one high-quality study, two medium, and five low-quality studies. Evidence demonstrated hypnosis reduced anxiety, improved patient cooperation, and supported better oral health outcomes by addressing anticipatory anxiety and avoidance behaviors. Conclusion: Hypnosis, combined with techniques like hypnotic communication and iatrosedation, offers a non-pharmacological strategy to manage dental anxiety and phobia. These approaches establish trust, redefine negative past experiences, and personalize patient care, leading to improved dental experiences and psycho-oral health. Implementing these methods in dental practice can enhance patient well-being and treatment outcomes
Ettore Rossi (1894-1968). «Ottimo architetto e tecnico ospedaliero»
No full text«Ciò che conta è curare e guarire i malati. Curare e guarire nel più breve tempo possibile [...]». Con tali obiettivi morali e funzionali, prima che formali e architettonici, Ettore Rossi progettò nel 1933 il Policlinico di Modena. Orientato già nella fase professionale romana a ideare edifici razionali e confortevoli, più volte apprezzati da Giuseppe Pagano che lo definì un «ottimo architetto e tecnico ospedaliero», nel Secondo dopoguerra Rossi trovò nell’edilizia sanitaria un campo a lui pienamente congeniale; specializzazione che, tuttavia, con la “diaspora” delle sue documentazioni progettuali, ha contribuito al parziale oblio che ha avvolto la sua ricca attività professionale
Angulated titanium bases screw channel abutments for single implant restorations: A systematic review and meta-analysis
No full textPurpose: Screw-retained implant crowns are a common solution to rehabilitate single or multiple edentulous sites. Angulated screw channel (ASC) abutments have been developed as a new system of connection to correct the angulation of the implant and avoid a possible undesired emergence of the access hole. The purpose of this systematic review was to examine available literature related to the effects of ASC abutments in rehabilitating single implant crowns. Methods: A protocol was registered in the PROSPERO database (ID = CRD42022295521). An electronic search of the Cochrane Central Register of Controlled Trials and Trial Protocols, MEDLINE, SCOPUS, and Web of Science was performed up to January 16, 2024. Additionally, a manual search was carried out. The meta-analysis used a fixed or a random effects model, based on the heterogeneity between the studies, focusing on binary and continuous data. A risk of bias assessment was performed (NOS or MOGA et al.) The outcomes assessed were peri-implant marginal bone level, probing pocket depth (PPD), the prevalence of technical and mechanical complications, implant and prosthesis survival rates, and esthetics. Statistical significance was set at p < 0.05. Results: The searches resulted in a total of 10 studies included in the meta-analysis. The mean implant and prosthesis survival rates were respectively 99% (absolute quantity = 243) and 100% (absolute quantity = 239) with non-statistically significant differences observed in single crowns supported by ASC abutments compared to cemented restorations, in terms of marginal bone loss (MBL) (p = 0.22), PPD (p = 0.08), risk of complications (p = 0.53), and esthetics (p = 0.47). Follow-up intervals ranged from 14 days to more than 3 years. Conclusions: Data based on this systematic review suggest that the clinical and radiographic outcomes of single implants restored using ASC are promising if compared to the outcomes relating to screw-retained single crowns
Small Inertia Limit for Coupled Kinetic Swarming Models
Get PDFWe investigate various versions of multi-dimensional systems involving many species, modeling aggregation phenomena through nonlocal interaction terms. We establish a rigorous connection between kinetic and macroscopic descriptions by considering the small inertia limit at the kinetic level. The results are proved either under smoothness assumptions on all interaction kernels or under singular assumptions for self-interaction potentials. Utilizing different techniques in the two cases, we demonstrate the existence of a solution to the kinetic system, provide uniform estimates with respect to the inertia parameter, and show convergence toward the corresponding macroscopic system as the inertia approaches zero
