Tesi di Dottorato

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3d web-based parallel applications for the numerical modeling of natural phenomena
(2014-11-28) Parise, Roberto; Leone, Nicola; D'Ambrosio, Donato; Spataro, William
In this thesis, I designed and implemented three new web applications tai- lored for the Cellular Automata (CA) simulation models SCIDDICA-k1, SCIARA-fv3 and ABBAMPAU, making use of the GoogleWeb Toolkit frame- work and WebGL. Moreover, I have contributed to the optimizations of the numerical models mentioned above and I also developed part of a library, called OpenCAL, for developing CA simulation models in C/C++. In this case, my most signi - cant contribution regarded the support given to the parallelization through the OpenCL standard, in order to facilitate with a few lines of codes, the par- allelization for the execution on any device, especially on General Purpose Computation with Graphics Processing Units (GPGPU). The development of the web applications involved the implementation of strategies so that optimizing the server load in the connections' management and enhancing the real time visualization of maps on devices of any kind, even mobile. As regards the OpenCAL library, the tests performed on a test models has shown signi cant performance improvements in terms of speedup, thanks also to the use of some new optimization strategies. In this way, the validity of the use of graphics processing units as alternative to more expensive hardware solutions for the parallelization of CA models has been con rmed.
40° N sole e contesto nella progettazione di spazi urbani mediterranei
(2009) Carbone, Ivana; Rossi, Franco; Cannavò, Paola
<> cloud-assisted, agent based framework for cyber-physical systems
(2016-02-19) Vinci, Andrea; Crupi, Felice; Spezzano, Giandomenico
<> Defect-Centric analysis of the channel hot carrier degradation
(2016-02-02) Pròcel-Moya, Luis-Miguel; Pantano, Pietro; Crupi, Felice
Durante l'ultimo decennio, il channel hot carrier (CHC) e stato considerato uno dei pi u importanti meccanismi di degrado della moderna tecnologia CMOS. La degradazione CHC si veri- ca quando un voltaggio superiore a quello di saturazione viene applicato sul terminale di drain e, contemporaneamente, un voltaggio superiore alla tensione di soglia (VTH) viene applicato sul terminale di gate. Nel presente lavoro, abbiamo utilizzato la cosiddetta defect-centric distribution (DCD) per spiegare e descrivere il meccanismo di degradazione CHC. Il DCD si basa su due presupposti: il VTH prodotto da una singola carica segue una distribuzione esponenziale (valore medio ) e il numero to- tale di difetti segue la distribuzione di Poisson (valore medio Nt). La combinazione di questi due presupposti da come risultato la DCD. Negli ultimi anni, la distribuzione DCD e stata usata per descrivere e spiegare la bias temperature instability (BTI) ed e in grado di predirre le code estreme della distribuzione VTH no a 4 . Il vantaggio di usare il DCD e che i suoi primi e secondi momenti sono direttamente correlati ai parametri sici e Nt. Nel presente lavoro, e stato dimostrato che il DCD e anche in grado di descrivere e spiegare il degrado della distribuzione VTH no a 3 . E stata studiata la dipendenza dei parametri de ect-centric, e Nt, in relazione alla geometria del dispos- itivo. E stato dimostrato che e inversamente proporzionale all'area del dispositivo come in la degradazione BTI. Inoltre, il valore previsto della distribuzione VTH (< VTH >) si incre- menta fortemente quando la lunghezza di canale (L) diminuisce e si incrementa debolmente con il decremento della larghezza del dispositivo (W). In la degradazione BTI, si riporta che non vi e alcuna dipendenza tra < VTH > ed L. Pertanto, la forte dipendenza trovata e da atribuire alla degradazione CHC. Si e anche studiata la dipendenza della temperatura (T) dei parametri defect-centric e abbiamo trovato che non dipende da T, al contrario degli esperimenti BTI, dove invece Nt aumenta con T, fatto che si spiega con l'attivazione del meccanismo di dispersione elettrone-elettrone. Inoltre, abbiamo estratto una energia di attivazione di 56meV per Nt. Finalmente, abbi- amo usato dispositivi matching-pair con la nalit a di studiare la variabilit a tempo zero e la variabilit a dipendente dal tempo. E stato dimostrato che il tempo di stress e la tensione di stress applicati sul terminale di drain non in uenzano la variabilit a.
<> methodology for the development of autonomic and cognitive internet of things ecosystems
(2018-06-08) Savaglio, Claudio; Crupi, Felice; Fortino, Giancarlo
Advancements on microelectromechanical systems, embedded technologies, and wireless communications have recently enabled the evolution of conven- tional everyday things in enhanced entities, commonly de ned Smart Objects (SOs). Their continuous and widespread di usion, along with an increasing and pervasive connectivity, is enabling unforeseen interactions with conven- tional computing systems, places, animals and humans, thus fading the bound- ary between physical and digital worlds. The Internet of Things (IoT) term just refers to such futuristic scenario, namely a loosely coupled, decentralized and dynamic ecosystem in which bil- lions (even trillions) of self-steering SOs are globally interconnected becoming active participants in business, logistics, information and social processes. In- deed, SOs are able to provide highly pervasive cyberphysical services to both humans and machines thanks to their communication, sensing, actuation, and embedded processing capabilities. Nowadays, the systemic revolution that can be led through the complete realization of the IoT vision is just at its dawn. As matter of facts, whereas new IoT devices and systems have been already developed, they often result in poorly interoperating \Intra-nets of things", mainly due to the heterogeneity featuring IoT building blocks and the lack of standards. Thus, the develop- ment of massive scaled (the total number of \things" is forecasted to reach 20.4 billion in 2020) and actually interoperable IoT systems is a challenging task, featured by several requirements and novel, even unsurveyed, issues. In this context, a multidisciplinary and systematic development approach is necessary, so to involve di erent elds of expertise for coping with the cy- berphysical nature of IoT ecosystem. Henceforth, full- edged IoT methodolo- gies are gaining traction, aiming at systematically supporting all development phases, addressing mentioned issues, and reducing time-to-market, e orts and probability of failure. In such a scenario, this Thesis proposes an application domain-neutral, full- edged agent-based development methodology able to support the main engineering phases of IoT ecosystems. The de nition of such systematic approach resulted in ACOSO-Meth (Agent-based COoperating Smart Objects Methodology), which is the major contribution of this thesis along with other interesting research e orts supporting (i.e., a multi-technology and multi- protocol smartphone-based IoT gateway) and extending (i.e., a full- edged approach to the IoT services modeling according to their opportunistic prop- erties) the main proposal. Finally, to provide validation and performance eval- uation of the proposed ACOSO-Meth approach, four use cases (related to di erent application contexts such as a smart university campus, a smart dig- ital library, a smart city and a smart workshop) have been developed. These research prototypes showed the e ectiveness and e ciency of the proposed approach and improved their respective state-of-the-art. ii
<> modelling study of atmospheric cycle of mercury and its exchange processes at environmental interfaces
(2015-12-18) De Simone, Francesco; Bertolini, Roberto; Carbone, Vincenzo; Pirrone, Nicola; HedgecocK, Ian M.
Since ancient times human activities have significantly altered the natural global Mercury (Hg) cycle through emissions to the environment. Hg is a global pollutant since its predominant atmospheric form, elemental Hg, reacts relatively slowly with the more abundant atmospheric oxidants and is therefore transported long distances from its emission source. Once oxidised however Hg is readily deposited, an can then be converted to the toxic monomethylmercury (MeHg) in soils and natural waters. MeHg is able to bioaccumulate and biomagnify, up to levels at which it is harmful to human health. Mercury pollution is therefore a threat to ecosystem health on a global scale, and is now being addressed by an international agreement, the Minamata Convention. Comprehensive knowledge of the details of the atmospheric Hg cycle is still lacking, and in particular there is some uncertainty regarding the atmospherically relevant reduction-oxidation reactions of mercury and its compounds. The exchange of Hg and its compounds between the atmosphere and the oceans also plays an important role in the cycling of mercury in the environment: understanding and quantifying mercury deposition patterns and fluxes is critically important for the assessment of the present, and future, environmental impact of mercury contamination. ECHMERIT is a global on-line chemical transport model, based on the ECHAM5 global circulation model, with a highly customisable chemistry mechanism designed to facilitate the investigation of both aqueous and gas phase atmospheric mercury chemistry. An improved version of the model which includes a new set of emissions routines, both on-line and off-line, has been developed and used for this thesis to investigate and assess a number of the uncertainties related to the Hg atmospheric cycle. Outputs of multi-year model simulations have been used to validate the model and to estimate emissions from oceans. Various redox mechanisms have been included to assess how chemical reactions influence the models ability to reproduce measured Hg concentrations and deposition flux patterns. To characterize the Hg emissions which result from Biomass Burning , three recent biomass burning inventories (FINNv1.0, GFEDv3.1 and GFASv1.0) were included in the model and used to investigate the annual variation of Hg. The differences in the geographical distribution and magnitude of the resulting Hg deposition fluxes, hence the uncertainty associated with this Hg source, were quantified. The roles of the Hg/CO enhancement ratio, the emission plume injection height, the Hg0 (g) oxidation mechanism and lifetime, and the inventory chosen, as well as their uncertainty were considered. The greatest uncertainties in the total deposition of Hg due to fires were found to be associated with the Hg/CO enhancement ratio and the emission inventory employed. Deposition flux distributions proved to be more sensitive to the emission inventory and the oxidation mechanism chosen, than all the other model parameters. Over 75% of Hg emitted from biomass burning is deposited to the world’s oceans, with the highest fluxes predicted in the North Atlantic and the highest total deposition in the North Pacific. The net effect of biomass burning is to liberate Hg from lower latitudes and disperse it towards higher latitudes where it is eventually deposited. Finally, the model was used to evaluate the fate of the Hg released into the atmosphere by human activities. Anthropogenic emissions are estimated to amount to roughly 2000Mg/y (1000-4000 Mg/y). Hg speciation (elemental, oxidised or associated with particulate matter) is subject to many uncertainties: the extremely variable lifetimes among Hg species, as well as the Hg emission heights, in combination with the complex physical and chemical mechanisms that drive its final fall-out lead to considerable uncertainties. To address this specific issue three anthropogenic Hg emission inventories, namely AMAP-UNEP, EDGAR and Streets, were included in the Model. Different model parametrisations were adopted to trace the fate of Hg to its final receptors and to thoroughly test the model performance against the measurements. Primary anthropogenic Hg contributes up to 40% of the present day Hg deposition. The oxidation mechanism has a significant impact on the geographical distribution of the deposition of Hg emitted from human activities globally, : 63% is deposited to the world’s oceans. The results presented in this thesis provide a new and unique picture of the global cycle of mercury, evaluating and assessing the uncertainties related to many aspects with an on-line Global Circulation Model developed specifically to investigate the global atmospheric Hg cycle.
<> proposal of efficient routing techniques and intelligent vehicular traffic management in the smart cities context, through distributed wireless networks
(2016-02-02) Sottile, Cesare; Pantano, Pietro Salvatore; De Rango, Floriano; Marano, Salvatore
In this thesis, the design of e cient techniques for routing protocol suitable to Vehicular Ad-hoc NETworks (VANETs) has been pro- posed. In particular, the aims of the proposed protocols are to reduce interference issues, due to the data transmissions in wireless environ- ment. The proposed protocols use time series prediction models and also multi-objective metric, based on the evaluation of co-channel in- terference levels, end-to-end delay, and link duration probability along the di erent links from sources towards destinations. These param- eters are modelled through an optimization problem. The key fac- tors are to exploit the advantages available to the Standard 802.11p, based on a dynamic allocation mechanism of the DSRC spectrum, aimed at the reduction of the co-channel interference and the maxi- mization of the link duration probability (two key issues in vehicular environments). Another topic discussed in this thesis is related to the smart vehicular tra c management through VANETs infrastructure and communications(V2I and V2V). A distributed algorithm with the aim to build less congested path for the vehicles in a urban scenario has been developed. It is also considered the problem regarding to enhance air quality around the cities reducing the vehicles CO2 emis- sions. There are di erent causes related to the CO2 emissions such as the average travelled time spent by vehicles inside the city and their average speed. Hence, with a better tra c management the average time spent by the vehicles in the city will be considerably reduced as well as CO2 emissions. These results are demonstrated in a discrete event simulator by using also real tra c data
<> study wind behavior from the micro to the mesoscale of different temporal and spatial horizons: turbulent regime, mean and climate
(2014-11-13) Tiriolo, Luca; Bartolino, Roberto; Sempreviva, Anna Maria; Carbone, Vincenzo
Absorpitive losses mitigation in gain-plasmon hybrid systems as optical metamaterials
(2013-11-29) Rashed, Alireza Rahimi; Bartolino, Roberto; Versace, Carlo C.; Strangi, Giuseppe
In the past decade, plasmonic nanoparticles (NPs) have gained a lot of interest due to their exceptional and fascinating properties which have been accomplishing vital role in emerging science and technology towards multifunctional applications. The extensive current research efforts in nanoplasmonics trigger towards various opto-electronic and medical applications such as invisibility, perfect lens, increasing the efficiency of solar cells, designing and extra-sensitive single-particle detection of biomolecular recognition and in particular optical metamaterials. The negative real part and the low value of the imaginary part of dielectric permittivity are crucial for applications of nanoparticles as subunits of optical metamaterials. However, the performance of plasmonic nanostructures is significantly limited by the intrinsic and strong energy dissipation in metals, especially in the visible range. In fact, regardless of the challenges to synthesize plasmonic nanostructures, the path to use them as building blocks of optical metamaterial is crossing through the finding a solution to mitigate their optical losses. In this research thesis, it is demonstrated experimentally that the incorporation of gain material such as organic dye molecules and quantum dots in close proximity of enhanced local fields of various properly designed plasmonic systems makes it possible to induce resonant energy transfer processes from gain units to plasmonic nanoparticles, to accompanish loss compensation in optical metamaterials. Steady-state experiments and time resolved spectroscopy along with modification of Rayleigh scattering and optical transmission of a probe beam as a function of impinging energy are crucial evidences of mitigation of absorptive losses in different gain doped plasmonic systems The strategy that has been followed here towards mitigation of absorptive losses in optical metamaterials acts at different spatial scales from nano to macro (see Figure 1). The systems at nano-scale (10-100 nm) are based on dispersion of NPs, in particular, gain assisted (nanoparticle-dye dispersion), gain-functionalized core-shell gold NPs (encapsulated dye molecules into the shell) and dye grafted gold core multimeric nanostructures. The study of such nano-composites allows to recognize experimentally how the parameters such as the geometry and size of the metal nanostructures, inter-particle distance, overlap between emission spectrum of gain material and plasmon band of metal NPs, concentration and quantum yield of donor molecules are playing an important role to create more efficient nonradiative RET processes from donor molecules to acceptors. Figure 1 The followed spatial stages on this research study ranged from (a) nano-scale and (b) mesco scale towards (c) macro scale. The obtained results in nano-scale generate further motivations to move forward to study meso-scale (100-900 nm) plasmonic systems which include both dispersion (nanoshell composites) and bulk (periodic layers of gain materials and lossy metal elements) systems. The nanoshells which are consisted of dye doped dielectric core coated gold shell dispersed in ethanol solution are designed with an optimized ratio of core diameter and metallic shell thickness. The time resolved fluorescence spectroscopy results along with pump-probe experiments on nanoshells are convincing evidences for optical loss mitigation. Finally in third stage, the optical properties of gain-plasmon composites dispersed in PDMS host matrix as an example for bulk samples at the macroscopic scale (1 μm and beyond) have been investigated. The achieved results on this stage can help to design and fabricate such plasmonic structures that lead from fundamental physics towards practical applications. In this regard, the first four chapters provide the background concerning the main elements of this research work. The first chapter contains an introduction to the metamaterials. Second chapter describes the optical properties of plasmonic nanostructures. In third chapter, gain materials and the optical processes beyond these materials have been investigated. The fourth chapter deals with the optical properties of hybrid systems consisted of active materials and nano-plasmonic elements. After providing a brief introduction regarding the applied setups and instruments in this research study in chapter five, the last three chapters represent the acquired experimental results in each mentioned spatial scale. In chapter six, the optical properties of nano-scaled gain-plasmon systems in solution including gain-assisted, gainfunctionalized and dye grafted multimeric samples are investigated. Chapter seven explores the optical characteristics of dispersion of nanoshell sample as an example of the study in mesoscale. Finally, the thesis is completed with the study of the optical features of macro-scaled bulk samples based on core–shell type quantum dots and gold NPs dispersed in PDMS, and a short conclusion of this research study. This study emphasizes effective progress in materials science and paves the way towards further promising scientific research aimed to enable the wide range of electromagnetic properties of plasmonic metamaterials
Accumulazione soggettiva e produzione del comune nel laboratorio argentino
(2009) Visco, Giuliana; Fiocco, Laura
Accuracy aspects in flood propagation studies due to earthfill dam failures
(2015-10-30) Razdar, Babak; Costabile, Pierfranco; Costanzo, Carmelina; Macchione, Francesco
Flooding due to dam failing is one of the catastrophic disasters which might cause significant damages in the inundated area downstream of the dam. In particular, there is a need of trustworthy numerical techniques for achieving accurate computations, extended to wide areas, obtained flood mapping and, consequently, at the implementation of defensive measures. In general several key aspects are required for accurate simulations of flood phenomena which are ranging from the choice of the mathematical model and numerical schemes to be used in the flow propagation to the characterization of the topography, the roughness and all the structures which might interact with the flow patterns Regarding general framework discussed before this thesis is devoted to discuss two aspects related to accuracy issues in dam breach studies. In the first part a suitable analytical relation for the description of reservoir have been discussed and the second part the influence exerted by the methods used for computing the dam breach hydrograph on the simulated maximum water levels throughout the valley downstream of a dam, has been investigated. As regards the first aspect, the influence of reservoir morphology on the peak discharge and on the shape of outflow hydrograph have been investigated in the literature. The calculation of the discharge released through the breach requires the knowledge of the water level in the reservoir. It is considerable that the reservoir morphology in computational analyses cannot be expressed exactly by an analytical formula because of natural topography of the reservoir. For this reason, the information about reservoir morphology is usually published as a detail tables or plots which each value of elevation from bottom to top has a corresponding value for lake surface and reservoir volume. However, in the cases for which there is a scarcity of data, analytical expression can be obtained by interpolation of the values of the table. Usually one of the most suitable technique for interpolation data is using polynomial function but unfortunately utilizing this function for solving the problem demand several parameters. Using power function in numerical computations of breach phenomena would be advantageous, because this function is monomial type and only one parameter needs to be estimated. In this thesis, we want to present that this approach is very accurate and suitable to represent the morphology of the reservoirs, at least for dam breach studies. To reach this aim, 97 case studies have been selected from three different geographical regions in the world. The results of this research have been shown that the power function is suitable to obtain an accurate fitting of the reservoir rating curve using a very limited number of surveyed elevations and volumes or areas. Furthermore in this part of the research it has been shown that two points are enough for a good fitting of the curve, or even only one if volume and surface are both available for an elevation close to normal or maximum pool. Results obtained for dam breach calculations using this equation, have the same quality of those achieved using the elevation-volume table. Moreover, this research have been shown that the exponent of power equation can be expressed by a formula which has a precise morphological meaning, as it represents the ratio between the volume which the reservoir would have if it were a cylinder with its base area and height equal to the respective maximum values of the actual reservoir, and the real volume of the reservoir. Regarding the second aspect, over the complexity of the mathematical models which have been used to predict the generation of dam breach hydrograph, it is considerable that the historical observed data of discharge peak values and typical breach features (top width, side slope and so on) have been usually utilize for model validation. Actually, the important problem which should be considered here is traditionally focused on what has been observed in the dam body, because the effects of the flood wave realized in the downstream water levels usually have been neglected. This issue seems considerable because required information for the civil protection and flood risk activities are represented by the consequences induced by the flood propagation on the areas downstream such as maximum water levels and maximum extent of flood-prone areas, flow velocity, front arrival times etc. The water surface data is almost never linked to the reservoir filling/emptying process which can be important information for the estimation of discharge coming from the breach, are available. Moreover, it is quite unusual to have records on the flood marks signs or other effects induced on the river bed, or on the man-made structures, downstream. For this reason finding well documented case study is one of the important part of any simulation study, especially for model validation. One of the few cases in this context is represented by the Big Bay dam, located in Lamar County, Mississippi (USA), which experienced a failure on 12 March 2004. In general analyzing the simplified models for dam breach simulation is the main purpose of this second important activity of the thesis. The simplified model have been utilized in this study, in order to identify a method that, on the basis of the results obtained in terms of simulated maximum water levels downstream, might effectively represent a preferential approach for its implementation not only in the most common propagation software but also for its integration in flood information systems and decision support systems. For the reasons explained above, attention here focuses on the parametric models, widely used for technical studies, and on the Macchione (2008) model, whose predictive ability and ease of use have been already mentioned. To reach this purpose both a 1-D and 2-D flood propagation modelling have been utilizing in this study. The results show that the Macchione (2008) model, without any operations of ad hoc calibration, has provided the best results in predicting computation of that event. Therefore it may be proposed as a valid alternative for parametric models, which need the estimation of some parameters that can add further uncertainties in studies like these.
Acquisizione ed elaborazione dati di irraggiamento ed illuminamento solare nuove correlazioni di calcolo
(2014-05-12) De Rose, Alessandro; Marinelli, V.; Rizzuti, S.
Across Scales Approach Based on Exciton-Plasmon Coupling for Low Loss Optical Metamaterials
(2015-12-15) Dhama, Rakesh; Bartolino, Roberto; Versace, Carlo; De Luca, Antonio
Action of the E2/ERβ/PTEN signaling in the metabolic reprogramming of TCam 2, human melanoma cell line
(2019-03-21) De Rose, Daniela; Andò, Sebastiano; Aquila, Saveria
I tumori maligni più abbondanti nella popolazione maschile di età compresa tra i 17 ed i 45 anni, sono i tumori delle cellule germinali (GCTs). Essi comprendono un gruppo eterogeneo di neoplasie in termini istologici, di marker d’espressione ed età di manifestazione. I tumori delle cellule germinali testicolari negli adolescenti e negli adulti (TGCTs) possono essere classificati in tumori seminomatosi (GCT di tipo II) e non seminomatosi. Nel nostro studio prenderemo in considerazione il GCT di tipo II, utilizzando come modello sperimentale la linea cellulare TCam2, ad oggi unica al mondo ampiamente caratterizzata e comprendente tutte le caratteristiche del seminoma umano, originata dalla lesione primaria di un seminoma testicolare sinistro di un paziente di 35 anni. La difficoltà di avere un modello cellulare valido per i tumori seminomatosi è il motivo principale che rende il tumore testicolare uno dei tumori meno studiati. La ricerca sul cancro testicolare continua ad investigare e studiare terapie volte ad indurre la morte nelle cellule tumorali. Recentemente, il metabolismo energetico è considerato un obiettivo innovativo nelle terapie antitumorali, in quanto le alterazioni metaboliche sono una caratteristica comune dei tessuti cancerosi. Il fenotipo metabolico maggiormente caratterizzante e per prima osservato nelle cellule cancerose è quello conosciuto come Effetto Warburg, che prevede la produzione di ATP attraverso la glicolisi invece che attraverso la fosforilazione ossidativa, anche in presenza di normali concentrazioni di ossigeno (Barger JF et al. 2010). Tuttavia, la riprogrammazione metabolica nei tumori si estende oltre l'Effetto Warburg. In effetti, la teoria classica sul metabolismo delle cellule tumorali (aumento dell'attività glicolitica e down-regolazione della fosforilazione ossidativa) è ancora oggetto di indagini in quanto numerosi studi hanno dimostrato che le cellule tumorali possono vivere in un ampio spettro di stati bioenergetici che variano dalla predominanza del fenotipo glicolitico, glicolitico parzialmente ossidativo, fino a quello prevalentemente fosforilativo (Smolková K et al. 2011). Gli estrogeni ed i loro recettori, sono in grado di modulare diversi aspetti del metabolismo cellulare come quello glucidico o lipidico, un’alterazione dei loro pathways trasduzionali è stata correlata infatti allo sviluppo di malattie metaboliche (Faulds Malin Hedengran, 2012). Nel nostro precedente studio abbiamo evidenziato un link tra ERβ/PTEN che attivato dall’estradiolo, induce la morte di tali cellule mediante autofagia e necroptosi (Guido C. et al. 2012). Poiché, morte cellulare e metabolismo energetico sono strettamente correlati, abbiamo ipotizzato che il link E2/ERβ/PTEN possa indurre una alterazione anche nella riprogrammazione metabolica nelle cellule di SE. Il ruolo di PTEN nella sopravvivenza e proliferazione cellulare è stato già riportato, inoltre PTEN è in grado di influenzare alcuni pathways metabolici come il metabolismo del glucosio (Madeline B, 2002), ed il metabolismo lipidico (Qiu W. 2008; Juan Liu, 2012; Ana Ortega-Molina and Manuel Serrano, 2013). Lo scopo di questo studio è quello di investigare un potenziale cross-talk funzionale tra E2, ERβ e PTEN nell’interferire sulla riprogrammazione metabolica delle cellule TCam2 di seminoma umano, così da ampliare le nostre conoscenze sul ruolo e sulla regolazione del gene PTEN oltre che sulla biologia di questo tipo di tumore. I nostri dati evidenziano un nuovo ruolo dell’ERβ come tumor suppressor, indicando che il meccanismo attraverso cui l’E2 induce la morte delle cellule TCam2 avviene anche attraverso l’alterazione della riprogrammazione metabolica in cooperazione con il gene PTEN. Ad oggi, il metabolismo di questa linea cellulare non è stato ancora investigato e pertanto il nostro lavoro contribuirà a migliorare le conoscenze su questo aspetto della biologia del seminoma umano. Concludendo, i nostri risultati supportano l’idea di una dipendenza estrogenica del tumore testicolare come già riportato in letteratura, indicando l’ERβ come possibile target terapeutico per il trattamento di questa condizione patologica.
Activated FXR inhibits leptin signaling and counteracts tumor-promoting activities of cancer-associated fibroblasts in breast malignancy
(2017-06-12) Vircillo, Valentina; Andò, Sebastiano; Catalano, Stefania
Cancer-associated fibroblasts (CAFs), the principal components of the tumor stroma, play a central role in cancer development and progression. As an important regulator of the crosstalk between breast cancer cells and CAFs, the cytokine leptin has been associated to breast carcinogenesis. The nuclear Farnesoid X Receptor-(FXR) seems to exert an oncosuppressive role in different tumors, including breast cancer. In this study, we demonstrated, for the first time, that the synthetic FXR agonist GW4064, inhibiting leptin signaling, affects the tumor-promoting activities of CAFs in breast malignancy. GW4064 inhibited growth, motility and invasiveness induced by leptin as well as by CAF-conditioned media in different breast cancer cell lines. These effects rely on the ability of activated FXR to increase the expression of the suppressor of the cytokine signaling 3 (SOCS3) leading to inhibition of leptin-activated signaling and downregulation of leptin-target genes. We further extend our data investigating whether FXR agonist may directly influence CAF phenotype. We demonstrated that FXR is expressed in different CAFs and treatment with GW 4064 is able to induce the transcription of key FXR target genes, including SHP (Small Heterodimer Partner) and BSEP (Bile Salt Export Pump). Interestingly, FXR activation is able to significantly reduce CAF motility, without influencing their proliferation capabilities. Accordingly, IPA (Ingenuity Pathway Analysis) on FXR-modulated genes highlighted cellular movement as the most significantly represented biologic process and evidenced a marked reduction in the activity of Rho signaling and Integrin proteins, with activation z-score of -1, -0,5 respectively. Moreover, our data showed a reduction in stress fibers formation in GW 4064 -treated CAFs. Activated FXR is able to reduce tumor promoting effects of CAFs on breast cancer cells, due to the ability of GW 4064 to reduce CAF secreted soluble factors, including IGF-1 (Insulin Growth Factor-1), FGF-9 (Fibroblast Growth Factor 9), TGF-3 (Transforming Growth Factor Beta 3) and others key mediators involved in the crosstalk tumor-stroma. Indeed, our data demonstrate how ER-breast cancer cell lines, MCF-7 and T47D, cocoltured with conditioned media derived from GW4064-treated CAFs, exhibit a significantly reduced anchorage-independent growth and migration. In vivo xenograft studies, using MCF-7 cells alone or co-injected with CAFs, showed that GW4064 administration markedly reduced tumor growth. Thus, FXR ligands might represent an emerging potential anti-cancer therapy able to block the tumor supportive role of activated fibroblasts within the breast microenvironment
Active plasmonic nanostructures for biomedical applications
(Università della Calabria, 2020-03-27) Chatterjee, Sharmistha; Bartolino, Roberto; Strangi, Giuseppe
Real-time and label-free detection of protein molecules at ultralow concentration in their natural state is considered the “Holy-Grail” in biomedical research. Protein molecules pop up in the bodily fluids such as saliva, blood serum, at early stage of any infection or disease and circulate throughout the body. Therefore, the emergence of that particular infection or disease can be envisioned through the detection of the signature protein markers. The early detection of the disease would help to start the treatment early, and thus ensure therapeutic success which will eventually increase the survival rates and quality of life. The early detection of protein molecules is necessary for the diagnostics as well as for environmental monitoring, emergency response and homeland security. But the desired detection of protein molecules in the early stage is extremely challenging because of the ultralow concentration of the protein markers in the bodily fluid at the early stage and their acutely small size (< 3 nm). One way to overcome this hurdle is to use the extraordinary electromagnetic responses of noble metal nanoparticles (MNPs). Here stable gold nanostars (AuNS) have been synthesized to use their property for sensing. A surfactant-free, simple, one step wet-chemistry method was used to synthesize these spiky nanoparticles, which were stable in aqueous media for more than five months. Based on their characterization and the numerical analysis, it has been realized that these nanoantennas could be an efficient agent for the early detection of disease. Furthermore, for the marker detection, the heterodimeric nanogap, created between a nanostar antenna tip and a gold nanosphere, was seen to be more effective than those single nanostar antennas because of their higher intensity enhancement capability and also the optimum electric field map at the hot-spots which acts as the binding site for molecule. Both the AuNS antenna and the hybrid one could be easily converted to a biosensor, by anchoring suitable anti-bodies on the surface of the nanoantenna. Surprisingly, these gold nanostar antennas were seen to have both the non-edge breathing modes and the well-known edge dipolar mode. The optically active edge dipolar mode will be useful for the detection of protein molecules by using their localized surface plasmon resonance (LSPR) effect which is same as any conventional plasmonic biosensor. But the non-edge breathing modes of nanostar antenna will be helpful to determine the mass of adsorbed analyte based on the cantilever principle. The mass estimation (having the information about the polarizability and the size) of the markers is very crucial because it would provide the information about the number of amino acids present in that molecule which will help for better understanding of its molecular structure and thus will be useful for designing its anti-agent. This efficient acousto-plasmonic nanoantenna therefore could become a key element at a point of care. To go one step forward in this research area, Fano-lineshape based sensing was thought to be a promising idea. Here the reported Fano line-shape arises from the coupling of the gold nanorods dipped in thermo-responsive polymer matrix and a silver thin film. The Fano system was seen to respond to both the change in external temperature and the refractive index. This kind of Fano system will be helpful for the label-free detection of the foreign protein molecule with high efficiency and also for identifying the marker’s thermodynamic state and reactions of the molecule which is crucial for protein engineering. All these constitute the base of the discussion of part I of the thesis which is about the light harvesting plasmonic nanoantennas. In the 2nd part of the thesis, AZO metasurfaces and their optical activities are discussed. Aluminium doped Zinc Oxide (AZO) is a low-loss material and popular as an alternate plasmonic material. The highly ordered AZO nanotubes array system has seen to have gas sensing capability. The reported H2 gas detection within a very short time can make this system suitable for industrial application. The detection of H2 gas of lower concentration with the help of these nanostructures is also useful to detect the presence of bacteria by tasting their exhaled H2 gas. On the other hand, the AZO solid nanopillars arrays are seen to have generalized Brewster angle phenomena which can be useful for many applications including the optical switching. Lastly, some additional works have been described in a brief way. In this section, photonic nanojet related theoretical study, asymmetric sound transmission behaviour shown in 3D printed acoustics metamaterials, focal-length tunability of metalens and plasmon assisted cancer therapy has been reported. As per my belief and understanding, all these studies reported in this thesis will enrich the related research areas.
Active plasmonics in soft matter doped with gold nanoparticles plasmonica attiva in materia soffice drogata con nanoparticelle d'oro
(2013-11-29) Cataldi, Ugo; Bartolino, Roberto; Caputo, Roberto; Versace, Carlo C.
The main objective of this study is active plasmonics. The work has been focussed on the design, characterization and theoretical interpretation of novel systems. Top-down and bottom-up, self-assembling, approaches have been utilized to realize devices where spherical gold nanoparticles have been periodically and randomly arranged. Two main paths have been followed to achieve this goal. In the first one, by utilizing a rigid periodic structure as a host platform for soft-matter (cholesteric liquid crystals) mixed with plasmonic nano-entities, was possible to obtain a chirally-organized tuneable plasmonic system. The tunability of the obtained device has been induced by applying temperature changes or external electric fields. In the second one, the surface of an elastomeric platform has been randomly covered by gold-nanoparticles. Controlled nano-chemistry processes have been successively applied to the nanoparticles (immobilized on the surface) to locally increase their size. The elastic properties of the template together with the increased size of particles have allowed a systematic study of the coupling between near-fields of the spherical nanostructures. Colloidal nano-chemistry technics have been utilized both to synthetize spherical gold nano-particles and to increase their sizes. Spectroscopic analysis has been used to analyse the response of obtained structures under electrical, thermodynamical and mechanical stimuli. SEM and TEM imaging have been exploited to study the morphology of devices, the shape of nano-structures and to measure their sizes. Moreover, from SEM images, through the use of a MatLab code written to the purpose, it has been possible to extract fundamental parameters used to perform a theoretical analysis of experimental results
Adaptative response of Posidonia oceanica (L.) Delile leaves to salt water and to depth: PoPIP1;1 aquaporin involvement and anatomical strategies evolution
(2009) Nicastro, Silvia; Musacchio, Aldo; Innocenti, Anna Maria; Giuseppe Passalacqua, Nicodemo Giuseppe
Adeguamento antisismico di edifici in c.a. irregolari in pianta mediante l'utilizzo di controventi dissipativi: modellazione, progettazione ed analisi non lineare
(2017-06-16) Pedace, Emilia; Furgiuele, Franco; Mazza, Fabio
Adsorption properties of carbon nanotubes and application of thermal desoprtion spectroscopy to ammonia and methane ices and zoisite
(2010-12-14) Vasta, Roberta; Bonanno, Assunta; Falcone, Giovanni
In this work we wanted to underline the importance of Thermal Desorption Spectroscopy and its applications to several branches of Physics. Temperature-programmed desorption techniques (TPD) are important to determinate kinetic and thermodynamic parameters of desorption processes and decomposition reactions. Knowledge of the nature of the desorption process is fundamental to understand the nature of the elementary chemical processes of adsorbates, as the energetics of bonding, the specification of the chemical nature of the bound species and the nature and magnitude of interactional effect between adsorbed species. We focused our attention on the applications of Thermal Desorption Spectroscopy (TDS) to High-Energies Physics, Astrophysics and Geophysics; in fact this technique was used, respectively, to investigate the molecular hydrogen adsorption on carbon nanotubes, the effects of electron bombardment on ammonia and methane ices and changes of zoisite mineral after heating. The molecular hydrogen adsorption on carbon nanotubes was studied to find a possible solution to vacuum system problems of Large Hadron Collider (LHC); in fact, the circular path of photon beams produces synchrotron radiation which deteriorates LHC vacuum desorbing gas molecules from the ring walls. Among the desorbed species the most problematic to pump out is H2. Since LHC elements operate at low temperatures, a possible solution to vacuum problem is the installation of cryosorbent materials on the LHC walls. In this work we study the possibility to use carbon nanotubes as criosorbers in future accelerators. Our sample, furnished by Prof. Nagy group of Chemical Engineering Department of Calabria University, is constituted by MWNTs synthesized by chemical vapor deposition using C2H4 and subsequently purified. Our investigations confirm that the carbon nanotubes have a great adsorption capacity also at low temperatures both for H2 and noble gases as Kr; then we observed that H2 adsorption on CNT is described by a first kinetic-order, while Kr adsorption is characterized by a zero kinetic-order. By means of TDS we calculate the activation energy for H2 adsorption on carbon nanotubes and we found a value of about 3KJ/mol, perfectly coherent with theoretic one. Moreover, from a comparison between nanotubes and other carbon-based material (as charcoal), we noted that adsorption efficiency for CNT is almost an order of magnitude higher then charcoal. So carbon nanotubes are good candidates to cryosorbers in future accelerators. 2 As Thermal Desorption Spectroscopy application to Astrophysics we studied the effect of electron bombardment on ammonia and methane ices. The interstellar medium is composed for 99% by gas; molecules, atoms and radicals at gas state condense on dust grains surface of molecular clouds (at 10 K) creating an icy mantle with a thickness of 0.1 μm. The presence of ices is confirmed by IR spectroscopy of obscured stellar sources and in interstellar grains are localized solid mixture containing H2O, CO, CH4 and NH3. In these environments ices are subjected to chemical and physical processes, specifically to bombardment of photons and cosmic rays, with the consequent synthesis of new organic species In this work we conducted an investigation of the chemical processing of ammonia and methane ices subjected to energetic electrons. By Thermal Desorption Spectroscopy we verify the production of new organic species, after energetic irradiation in interstellar ices, as diazene (N2H2), ethane (C2H6) and acetylene (C2H2). Finally, in Geophysics and Petrology Thermal Desorption Spectroscopy can be used to study minerals chemical composition. Our interest was focused on zoisite and the sample investigated was furnished by prof. Ajò from “Institute of Inorganic Chemistry and Surfaces” of CNR, in Padova. In this work we used TDS to investigate zoisite behaviour during heating form room temperature to 650oC and to understand if its modification into tanzanite variety after heating is due to structural changes or to a dehydration mechanism.