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Biomolecules from olive mill wastewater: cosmeceutical and nutraceutical applications
No full textOlive mill wastewater (OMWW), the main by-product of the olive oil industry, contain water, sugars, mineral salts and polyphenols. Hydroxytyrosol, the most abundant biophenol, has a lot of beneficial effects on human health, as anticancer activities.
The aims of my doctorate project were to evaluate:
1) possible differences in the chemical composition of OMWW generated from two Sicilian olive cultivar (Cerasuola and Nocellara etnea);
2) safety and the moisturizing properties of a sugars and minerals enriched fraction (SMEF), obtained from Cerasuola-OMWW, by in vitro and in vivo studies;
3) the chemotherapeutic activities in vitro exhibited by hydroxytyrosol-enriched fraction (H-EF) obtained from Cerasuola-OMWW. As control, we used hydroxytyrosol commercial standard (HTyr).
HPLC analysis evidenced a quantitative rather than a qualitative difference in the polyphenolic profiles of Cerasuola-OMWW and Nocellara etnea-OMWW. However, hydroxytyrosol and tyrosol were the most abundant biophenols present in both OMWW. Both waters were able to quench the DPPH radical and had a higher radical scavenging activity than the standard hydroxytyrosol, probably due to the synergistic effect of other phenolic compounds present in OMWW. Stability studies showed no significant changes in total phenolic, flavonoid and hydroxytyrosol content in both OMWW when stored at -20°C for 6 months.
The lyophilized SMEF was rich in sugars (around 43%) and potassium.
The in vitro study performed on MRC-5 cells has evidenced that:
- the lowest concentrations of lyophilized SMEF (0.5% and 1% w/w) did not influence cell viability either after 6 or 24 hours of treatment. Conversely, the highest concentrations (2%, 5% and 10% w/w) determined a drastic decrease of cell viability in a dose- and time-dependent manner;
- the degree of apoptosis and intracellular ROS levels increased, in treated fibroblasts compared to untreated controls, in a dose- and time-dependent way, in particular from 2% concentration to 5% w/w;
- the DNA damage extent increased for the 2% and 5% SMEF treatment only in a concentration-dependent manner;
- the treatment with the highest concentrations of SMEF for 6h induced early alterations of cell morphology as shrunken cytoplasm and numerous blebs and ruffles on the cell surface.
Taking into account these data, 1% w/w of lyophilized SMEF was incorporated in an emulsion to formulate a body cream, able to increase skin hydration, as shown by in vivo study.
H-EF added at different concentration in astrocytoma cells decreased cell viability, in a dose- and time-dependent manner, induced arrest in G1 phase and inhibited cell migration. These data are in accordance with the observed time-dependent increase in DNA damage and the decrease in p53 and p21 expression. An increase in ROS level with a parallel decrease in GSH level seemed to be involved in the genotoxic effect-H-EF- induced in astrocytoma cells. In addition, by investigating some possible epigenetic effects exerted by our extract, we observed a modulation of global DNA methylation expressed as hypomethylation at lowest concentration (50 µM) and hypermethylation when the cell treatment was performed at 100 µM. The additional epigenetic parameters we studied, SIRT1 expression and nuclear sirtuins activities, were both decreased.
We observed different dose- and time-dependent effect for hydroxytyrosol (HTyr) 100 µM. The compound did not influence cell viability either after 24 or 48 hours of treatment but induced an arrest in S phase at 24 h and in G1 phase only at 48 h. In addition, it increased p53 expression without inducing any change in p21 expression and, finally, it hypomethylated DNA and increased both SIRT 1 expression and nuclear sirtuins activity.
We demonstrated the potential use of SMEF and H-EF in cosmeceutical and nutraceutical field. However, the possible therapeutic use of H-EF in humans requires additional studies
In solution-doping of PEDOT:PSS for highly conductive polymer films with tunable optical properties
No full textPEDOT:PSS is one of the most known conductive polymers, but, despite its great popularity and numerous studies carried on it, the scientific production still shows a lack on this material. This concerns the acidic doping carried by H2SO4 by an in-solution approach. Hence, the aim of this work was to investigate the effects due to the direct acidification of PEDOT:PSS solution. This thesis thus presents a step-by-step study of this novel approach, describing the characteristics of the pristine polymer first, and of its acidified forms then. Results obtained showed a marked improvement of the electrical properties, with also a great versatility in terms of optical and tribological features, until obtaining a plastic, free-standing material with high potentiality. The mechanism behind the proposed method is described, suppling new insights and perspectives. Finally, a novel approach of the block copolymer self-assembly is also described as a use proposal of the material developed
Libertà Fondamentali e Diritto di Proprietà nella Russia Post-Sovietica
No full textIl presente elaborato intende tracciare un affresco dei peculiari sviluppi del costituzionalismo russo attraverso la comparazione tra il modello delle Costituzioni sovietiche e quello, formalmente diverso, della Costituzione post-sovietica del 1993. L angolo prospettico per svolgere siffatta comparazione è quello della disciplina delle c.d. libertà economiche o, come suole dirsi, della costituzione economica russa nel suo evolversi storico. In particolare, si è ritenuto opportuno centrare il focus dell indagine sul diritto di proprietà e sul peculiare regime per esso previsto nell ordinamento della Russia sovietica e post-sovietica. Necessariamente, lo studio delle libertà economiche (e dei diritti ad esse correlati) si traduce, in chiave giuridico-costituzionale, in una riflessione sul rapporto tra modello economico e democrazia. Da qui, l esigenza di osservare lo stato (e lo stadio) della neo-democrazia russa dall analisi della costituzione economica , formalmente stabilita dalla Costituzione del 1993, che altrettanto formalmente sembra ispirarsi ai modelli delle liberal-democrazie occidentali, nonché di (tentare di) comprendere se l ispirazione a un preciso modello economico (e democratico) si sia tradotto, nella Russia post sovietica, nella concreta ed effettiva adesione a siffatto modello
Compact architectures for dc-dc converters with galvanic isolation
No full textThis thesis summarizes the main activities that I have been carried out during three years of Ph.D. studies at the RF-ADC, a joint research group between University of Catania and STMicroelectronics Catania.
Recently, galvanic isolation for both power supply and data communication is becoming mandatory in several application fields to guarantee safety and reliability, especially in harsh operative environments. A wide range of applications adopts galvanic isolation, e.g., sensor interfaces, serial link transceivers, low-power medical devices, and housekeeping power, such as gate-drivers or controllers for power converters. By referring to the main limitations of the state of the art solutions, this work presents three novel architectures, which implement galvanically isolated dc dc converters with different target of applications. The main object of the proposed systems is the reduction of the number of isolated links while preserving both power and data functionalities
Studio sull'incremento dell'efficacia e della qualità dei trattamenti di protonterapia
No full textThe research in protontherapy is being configured today a new era where new objectives in term of quality treatment improvement are reached and new methodologies to increase the radiobiological effect are investigated. This thesis includes both these aspects. The first part of the work is dedicated to a new proposed methodology based on a nuclear reaction triggered by clinical protons. I report the first experimental proof of the PBCT (Proton Boron Capture Therapy) technique based on the use of the p+11B=>3a nuclear fusion reaction to enhance proton biological effectiveness exclusively in the tumour region through the generation of short-range high-LET alpha particles, thus being of potential clinical worth.
Another important item in the protontherapy research consists of investigations about the improvements in the treatments quality. In this thesis, Monte Carlo approach has been evaluated as a new promising strategy for the calculation of the main parameters of interest in medical physics and radiobiological applications. A systematic study to identify the best algorithm for the Linear Energy Transfer (LET) calculation has been performed. This resulted in a new proposed algorithm and its application for the radiobiological effect estimation (or RBE).
A work on the proton therapy quality improvement cannot neglect a precise beam characterization as well as the optimisation of its transport parameters. Accordingly, a special task was focused on the improvement of the INFN (Istituto Nazionale di Fisica Nucleare) multidisciplinary facilities: LNS (Laboratori Nazionali del Sud) and TIFPA (Trento Institute for Fundamentals Physics Applications). The main intent has been to increase the beam quality and the techniques for its monitoring. Systematics studies to realize a scattering system for high energy proton and light ions beams (12C, 4He, 16O) as a well as a passive system for the beam energy modulation have been performed. In the end, a new detector for the online dose profiler acquisition has been developed and characterized for its future installation in the abovementioned facilities
Allelopathic effects of Cynara cardunculus L. extracts
No full textThe present doctoral thesis aims to explore the potential use of Cynara cardunculus L. leaf extracts for the biological control of weeds and pathogen microorganisms. In a first trial, the allelopathic effects of its leaf aqueous extracts on seed germination of six common weeds was demonstrated. Secondly, the set-up of the most efficient extraction method of its allelochemicals in terms of costs, yields and inhibitory activity was realized, selecting dried leaves as the best plant material and ethanol and ethyl acetate as the best solvents. Moreover, new C. cardunculus allelochemicals (cynaratriol, desacylcynaropicrin, 11,13-dihydro-desacylcynaropicrin and pinoresinol) were purified. Third, the effect of genotype, harvest time and light stress on the phytotoxicity, quantity and composition of sesquiterpene lactones in C. cardunculus leaf extracts was evaluated through a new UHPLC-MS/MS analysis method. Wild and cultivated cardoon showed the highest concentrations, while the April harvest revealed the best harvest time. Moreover, light stress stimulated the production of these allelochemicals. In a second trial, the effects resulting from three consecutive years of cultivation, in two different areas, with globe artichoke, cultivated and wild cardoon on the quali/quantitative weed soil seed bank and the changes in the eubacterial communities were studied. In both areas, C. cardunculus reduced weed seed bank in all treatments compared to controls. Nevertheless, the presence of cultivated cardoon had a negative influence towards Bacillus subtilis and a positive one on Pseudomonas putida and Azospirillum brasilense. Lastly, cultivated cardoon leaf extracts were assessed in vitro for the control of several microorganisms of agriculture and food interest. All the extracts showed an important antimicrobial activity
Security and privacy in 5G
No full textThe current advancements of communication systems and their applications have changed our lives and will influence them further in the future. Next generation 5G networks will represent a salient technological breakthrough that combines old and new technologies and involves, among all, new models of service provisioning and resource sharing. In particular, they will lead to the emergence of mechanisms and architectures towards the on-demand multi-tenant philosophy. In this new eco- system, it will be necessary to address the trust question among stakeholders as well as their security.
The 5G revolution brings new pitfalls due to novel forms of human-to-device in- teractions and the even higher pervasiveness of the technology in human life. As an example, in the Internet of Things (IoT), devices equipped with sensing, processing, storage and decision-making capabilities, can actively interact with one another and with humans. Although their design could strictly adhere to the principles of pri- vacy and security, several factors, such as weak implementations of communication protocols, metadata information exchange, and architectural flaws, could jeopardise the security and privacy of their owners. Moreover, the augmented complexity and heterogeneity deriving from the ultra-densification of communication infrastructures, although it can improve data rate, reduce delay, and coverage of cellular networks, might raise new threats to the privacy of network subscribers.
In the first part of this thesis, we provide an overview of 5G networks and analyse the security, trust, and privacy problems in it. Then, we discuss the mutual impact of security and privacy of stakeholders and the use of semantic reasoning systems for the trust evaluation. In this vein, we studied the features of security ontologies that can influence the automated threat identification process and laid out a road towards ontologies simplification. In the second part of this thesis, we give a brief introduction to the privacy issues in the IoT. Then, we propose a methodology of analysis for identification of privacy threats in the IoT which can explore the privacy issue space from different perspectives and at various levels of abstraction. In the third part of this thesis, we explore the effect of both user equipment and access points densification on the location privacy.
We characterised the relationship between density of users and the success of at- tacks aiming at disclosing the location of subscribers. Hence, we propose a mitigation strategy founded on the concept of virtual cells
First observation of the Pygmy Dipole Resonance in the nucleus 68Ni using an isoscalar probe above the neutron emission threshold
No full textThe thesis concerns the investigation of the Pygmy Dipole Resonance (PDR) in the nucleus 68Ni.
Understanding the properties of the PDR is a current subject in the nuclear structure. From the study of the PDR properties, indeed it is possible to extract information regarding the neutron-skin of the neutron-rich nuclei and the symmetry energy of the Equation of State of the nuclear matter. Moreover, the PDR might influence also the r-process, responsible of the nucleosynthesis of elements heavier than Fe. Many theoretical approaches are able to describe the PDR and they predict a mixing between the isoscalar and isovector character of PDR. For this reason, various experiments have been carried out below the neutron emission threshold using both probes. The comparison between such experiments shows that only a group of states at low energies is excited by both probes, whereas another group, at higher energies, is populated just with the isovector ones. This observation, called isospin splitting, needs to be better understood. The investigation of the PDR in unstable nuclei has been carried out mainly using isovector probes.
We performed at INFN-LNS an experiment aimed to study for the first time the PDR in the 68Ni at 28A MeV using an isoscalar target of 12C. Semiclassical calculations indeed showed that the cross section of the PDR in the 68Ni + 12C at 28A MeV is mainly due to the nuclear contribution.
A 70Zn primary beam, accelerated to an energy of 40A MeV using the Superconducting Cyclotron, impinged on a 9Be target to produce the exotic beam delivered via the FRIBs@LNS facility. An appropriated tagging system was used to detect the 68Ni beam.
The main goal of the experiment was to study the -decay channel of the PDR, performing coincidence measurements between -rays, the 68Ni beam and 68Ni fragments. The CsI(Tl) scintillators of the CHIMERA multidetector were used to detect the -rays. While, the FARCOS array was used to detect the scattered 68Ni as well as other ions produced in the reaction.
The comparison between the -rays energy spectrum in coincidence with the 68Ni channel and the one in coincidence with the 66,67Ni allowed to evaluate the PDR -decay cross section. Moreover, we performed statistical calculations to extract the PDR strength. Such calculations were also useful to verify that the influence of other states, such as the Giant Dipole Resonance and Giant Quadrupole Resonance, in the region of the PDR, is negligible. We evaluated also the -rays angular distribution that shows the typical character of an E1 transition. Finally, we performed a comparison with previous experiments realized with an isovector probe. Such comparison did not show important differences in the PDR energy distribution. Therefore, the isospin splitting seems not to be present for unstable nuclei above the neutron emission threshold. Moreover, the configuration of the experimental set up has provided also preliminary information on the PDR neutron decay channel
Aggregation, Spatio-Temporal Structures and Well-Posedness in Chemotaxis Models of Inflammatory Diseases
No full textInflammation is the body's immune response to outside threats and traumas, aiming to prevent the insurgence of diseases. Although it is a protective mechanism, a derangement of the inflammatory response can lead to severe and debilitating diseases, such as Multiple Sclerosis. For this reason, understanding the mechanisms driving an inflammatory response has become one of the biggest challenge in immunology.
The subject of this Thesis is the study of mathematical models aiming to explore the mechanisms of the inflammatory response and the resulting clinical patterns. Our aim to prove that the proposed models, within biologically relevant ranges of the parameter values, are able to reproduce different pathological scenarios observed in patients
Coco-Russo method for Elliptic and Hyperbolic Equations on arbitrary domains
No full textIn this thesis we have presented a finite-difference ghost-point method to solve elliptic and hyperbolic equations on arbitrary domains. The equations are discretized on a uniform Cartesian grid. At first we applied the Coco-Russo method, which represents a generalization of the finite-difference method for the elliptic equations on arbitrary domains, at the resolution of the Poisson equation. This method proposes a polynomial interpolation technique to impose boundary conditions and therefore the interpolation error can influence the accuracy order of the method itself. We have proposed linear and bilinear interpolation techniques. These conditions are imposed on the projections of the ghost points on the border of the domain. The numerical tests performed on the behaviors of the inverse matrix of the method, of the error and of the consistency error confirm the stability and convergence of the Coco-Russo method in 1D, 2D and 3D, in the case of Dirichlet problems and in the case of mixed problems. We have also presented a rigorous proof of the stability and convergence of the numerical method in the one-dimensional case.
Once we certain of the convergence and stability of the Coco-Russo method, our interest it has moved to the study of the Euler equations of the gas dynamic. The Coco-Russo method was applied for the development of a semi-implicit method for Euler equations on domains that have obstacles, to impose boundary conditions in a manner similar to elliptic equations. This method being semi-implicit overcomes the problem of spatial restriction to guarantee the stability of the method typical of explicit methods