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Transmission Electron Microscopy studies of the nanostructural characteristics of the Inductively Coupled Plasma synthesized Silicon Nanowires
No full textThe aim of this work was devoted to the investigation of the properties and growth mechanism of Silicon nanowires (SiNWs) synthesized via an inductively coupled plasma (ICP) based process. To this purpose, three classes of Si nanostructures have been extensively studied, namely SiNWs, chapelet-like Si nanostructures and SiNC chains, produced by the novel technique of ICP. Focus has been put on the correlation between the structural characterization of the Si nanostructures and their optical properties, in order to understand the occurrence of QC effects related to their nanosize. An approach based on the use of Transmission Electron Microscopy techniques has been used to accomplish the investigation of the structural and chemical characteristics of the SiNWs, leading to the understanding of their growth mechanism. In a second step of this project, the effects of post-synthesis thermal treatments on the nanostructural changes of these SiNWs have been studied. All these results constitute a solid basis towards the production of SiNWs via the ICP technique. The ICP is a genuinely bulk process, which can be advantageously exploited for large scale fabrication of thin SiNWs needed to integrate Si into attractive large-area optoelectronic devices and flexible electronics
Study of an innovative non intrusive load monitoring system for energy emancipation of domestic users: hardware and ICT optimized solutions
No full textNon-intrusive appliance load monitoring (NIALM) is the process of disaggregating a household s total electricity consumption into its contributing appliances. Smart meters are currently being deployed on national scales, providing a platform to collect aggregate household electricity consumption data. Existing approaches to NIALM require a manual training phase in which either sub-metered appliance data is collected or appliance usage is manually labelled. This training data is used to build models of the household appliances, which are subsequently used to disaggregate the household s electricity data. Due to the requirement of such a training phase, existing approaches do not scale automatically to the national scales of smart meter data currently being collected.
In this thesis an unsupervised disaggregation method is presented which, unlike existing approaches, does not require a manual training phase. A NIALM system reads real-time data from a smart meter, usually positioned at the point on the public electricity network at which the customers is connected, and uses algorithms not only to quantify how much energy is used in the home, but also to determine what main devices are being operated. NIALM algorithms need a complete load signature and complex optimization algorithms to find the right combination of single loads that fits the real electrical measurements. It is practically impossible to get the detailed signature of all appliances inside a house/building and sophisticated optimization algorithm are not suitable for on-line applications. To do so, we address the following topics.
First, a straightforward NIALM algorithm is proposed, it is based on both a simple load signature, rated active and reactive power and a heuristic disaggregation algorithm.
Second, on real applications, this approach cannot reach very high performances; this is the reason why an active involvement of users is considered. The users feedback aims to: correct the load signatures, reduce the error of disaggregation algorithm and increase the active participation of users in saving energy politics.
Third, the NIALM algorithm has been accurately tested numerically using as input load curves generated randomly but under given constraints. In this way, the causes of inefficiency of the proposed approach are quantitatively analyzed both separately and in different combinations.
The above contributions provide a solution which satisfies the requirements of a NIALM method which is both unsupervised (no manual interaction required during training) and uses only smart meter data (no installation of additional hardware is required). When combined, the contributions presented in this thesis represent an advancement in the state of the art in the field of non-intrusive appliance load monitoring, and a step towards increasing the efficiency of energy consumption within households
Synthetic vs biological meshes: can in vitro cellular responses predict the outcome in patients? Literature review, experimental study and clinical experience in Day Surgery and inpatients related to the improvement of quality of life
No full textAbdominal wall hernia surgical repair is a common procedure (1) (2). Over time, hernia repair has evolved from predominantly primary suture repairs to tension-free repairs with synthetic mesh.
About one million prostheses are used worldwide for abdominal wall repair each year (6), but despite a substantial decrease in the recurrence rate after tension-free repair, the use of mesh is not without its own complications. In the attempt to reduce the possibility of complications related to synthetic mesh use, biological meshes in abdominal wall hernia repair were introduced.
Biological meshes are derived from humans and animals and become incorporated into the wound, acting as a scaffold for tissue repair, leading to a strong, well-healed, vascularised wound (17). Due to the nature of biologics, the adhesions associated with synthetic mesh should not occur and neovascularization should soon allow delivery of immune cells and antibiotics
Although biological meshes are gaining popularity, the exact molecular mechanism leading to host reaction and biological graft integration remains unclear and poorly understood by the surgical community.
In the first part of this thesis a review of all data available now about biological grafts and their interaction with tissue is presented. In the second part our laboratory results concerning interaction between different matrices (synthetic and biological) used in abdominal wall repair surgery and primary fibroblast cultures are reported. Finally, in the third part, our clinical experience with biological meshes is described
New products from Cynara cardunculus L.
No full textThe goal of the researches that make up the present study was to explore the potential of C. cardunculus L. to be exploited for some new uses.
Although the globe artichoke has deep roots in the culinary traditions of the Mediterranean countries, it requires nowadays innovations that remove the difficulties of its preparation and make it easier and faster to consume. The artichoke as a minimally processed and ready to use product addresses this need. The results presented in this thesis show that by choosing the right cultivar-packaging combination, it is possible to extend the shelf life of the product to at least 7 days from packaging.
The cultivated and wild cardoon produce large amounts of biomass, even under low-input conditions, thanks to their hardiness and the perfect match with Mediterranean climate. The data provided in this thesis confirm the cardoon as a possible source of renewable energy, both for its biomass yield and for biomethane yield of its silage. The volume of biomethane produced from the ensiled cardoon (between 200 and 250 Nm3 per t DM) is comparable to that produced by the ryegrass silage, triticale and wheat. Silage of cultivated cardoon genotypes achieved volumes of biomethane (from 3,700 to 4,530 Nm3 ha-1) that are comparable to those obtained with maize grown under an intermediate input intensity regime.
Much of the biomass produced by globe artichoke plants remains in the field as crop residues, this biomass can be exploited for the production of bioethanol, considering its richness in complex carbohydrates (cellulose and hemicellulose) and even in simple sugars (glucose and fructose ). The enzymatic saccharification of non-pretreated biomass of residues of two globe artichoke cvs. ('Opera F1' and Spinoso sardo') has given rise to a potential yield of 85-109 kg of EtOH per t DM and 1,440-1,520 kg of EtOH per ha
Biomolecular effects and bioclinical applications of PARPs inhibitors
No full textAbstract Section I
Inhibitors of PARP-1(Poly(ADP-ribose) polymerase-1) act by competing with NAD+, the enzyme physiological substrate, which play a protective role in many pathological conditions characterized by PARP-1 overactivation. It has been shown that PARP-1 also promotes tumor growth and progression through its DNA repair activity. Since angiogenesis is an essential requirement for these activities, we sought to determine whether PARP inhibition might affect rat brain microvascular endothelial cells (GP8.3) migration, stimulated by C6-glioma conditioned medium (CM). Through wound-healing experiments and MTT analysis, we demonstrated that PARP-1 inhibitor PJ-34 [N-(6-Oxo-5,6-dihydrophenanthridin-2-yl)-N,N-dimethylacetamide] abolishes the migratory response of GP8.3 cells and reduces their viability. PARP-1 also acts in a DNA independent way within the Extracellular-Regulated-Kinase (ERK) signaling cascade, which regulates cell proliferation and differentiation. By western analysis and confocal laser scanning microscopy (LSM), we analysed the effects of PJ-34 on PARP-1 expression, phospho-ERK and phospho-Elk-1 activation. The effect of MEK (mitogen-activated-protein-kinase-kinase) inhibitor PD98059 (2-(2-Amino-3-methoxyphenyl)-4H-1-benzopyran-4-one) on PARP-1 expression in unstimulated and in CM-stimulated GP8.3 cells was analyzed by RT-PCR. PARP-1 expression and phospho-ERK activation were significantly reduced by treatment of GP8.3 cells with PJ-34 or PD98059. By LSM, we further demonstrated that PARP-1 and phospho-ERK are coexpressed and share the same subcellular localization in GP8.3 cells, in the cytoplasm as well as in nucleoplasm. Based on these data, we propose that PARP-1 and phospho-ERK interact in the cytosol and then translocate to the nucleus, where they trigger a proliferative response.
We also propose that PARP-1 inhibition blocks CM-induced endothelial migration by interfering with ERK signal-transduction pathway
Digital Forensics Ballistics: Reconstructing the source of an evidence exploiting multimedia data
No full textThe Forensic Science (sometimes shortened to Forensics) is the application of technical and scientific methods to the justice, investigation and evidence discovery domain. Specifically finding evidences can be trivial and in many fields is achieved with methods that exploits manual processes and the experience of the forensics examiner. Though human factor can be often discussed and the evidences collected and found without repeatable and scientific methods could be of no use in tribunal. For these reasons this thesis focus on the investigation and development of classification engine able to uniquely identify and classify evidences in a scientific and repeatable way: each decision is driven by features and is associated by a confidence number that is the evidence itself. Two application in two different domains of Ballistics will be described: Image Ballistics, that is the reconstruction of the history of an image, and Fire Weapon Ballistics, that is the identification of the Weapon that fired an investigated bullet from the imprintings left on the bullet cartridge.
To understand how to solve these two real in-the-field problems, multimedia-based novel techniques will be presented with promising results both in Image and Classic Ballistics domain
Seismic Assessment and Rehabilitation of existing RC Buildings not designed to withstand earthquakes
No full textThis thesis presents a high fidelity numerical model developed to investigate the seismic performance and structural robustness of an original and retrofitted 10-storey reinforced concrete (RC) framed building. The analysed structure represents a typical existing building in Catania, Italy, that was designed to resist only gravity and wind loading according to the design regulation allowed until the 1981 in that area. The proposed numerical description adopts beam-column elements for beams and columns and special purpose shell elements for modelling RC floor slabs, both allowing for geometric and material nonlinearity. In order to model masonry infills, a novel macro-element is implemented within a FE framework based on an already published discrete formulation. 3D nonlinear dynamic simulations are performed considering sets of natural accelerograms acting simultaneously along all the three space directions and compatible with the design spectrum for the Near Collapse Limit State. To improve computational efficiency, which is critical when investigating the nonlinear dynamic behaviour of large structures, the partitioning approach previously developed at Imperial College is adopted, enabling effective parallelisation on HPC systems. The numerical results obtained from the 3D nonlinear dynamic simulations are presented and discussed, focusing on the variation in time of the deformed shape, inter-storey drifts, plastic deformations and internal force distribution, considering or neglecting the infill panel contribution. The original structure showed a very poor seismic performance, even though the infill panel contribution leads to significant variation in the response it is not sufficient to preserve the structure from the collapse. A never adopted strengthening solution that utilises the synergetic contribution of concentric steel bracing and eccentric steel bracings with dissipative shear links is illustrated and employed to retrofit the original structure. A detailed model of the retrofitting components is implemented within the detailed model for the original building. The results of numerical simulations for the retrofitted structure confirm that the proposed solution significantly enhances the response under earthquake loading, allowing the structure to resist the design earthquake with only limited damage in the original RC beams and columns, highlighting the feasibility of retrofitting for this typical multi-storey RC building structure
Progettazione multivariata di liquidi ionici sostenibilii ed efficienti
No full textIonic Liquids (ILs) attracted extraordinary attention due to their versatility in different applications. Their low vapour pressure reduces the air pollution as compared to common volatile organic solvents, but this property is not sufficient to define them as green solvents. In fact, release of ILs from industrial processes into wastewaters may lead to pollute aquatic environments due to their high solubility and stability. Sustainability and efficiency of ILs are both fundamental requirements for their industrial applications which boost the knowledge of ILs toxicological and environmental properties to comply with the European Union regulation (REACH). Unfortunately toxicity and sustainability are wide terms being determined on different possible targets. Furthermore, reliable toxicity tests when available in the literature, are reported for a specific class of compounds. In this context a multivariate insight allowed to compact available toxicity data into 104 toxicity scores [1] representative of the most common aquatic living targets.
The number of ILs resulting from the combination of cations and anions is estimated to be over a million, hence the ILs experimental space is so huge that it cannot be fully explored and requires a rational selection of highly informative experiments. The development of Quantitative Structure-Property Relationships (QSPRs) models implies the knowledge of structural descriptors for ILs. Unfortunately, experimentally determined physico-chemical properties in the case of ILs are very few, derived by different laboratories and scattered in the literature. To overcome this difficulty, we derived in silico cation and anion physico-chemical descriptors [2] by using the VolSurf+ approach. Such descriptors were tested in two QSPR models on ILs aquatic toxicity [2] and polarity [3], achieving good correlations and satisfactory predictions. Handling such a high number of descriptors may be difficult, especially for big ILs data sets. Consequently the descriptors were also compacted into few Principal Properties (PPs) [4] highly informative and suitable for multivariate experimental design. PPs can be used as descriptors in QSPR correlations to model both ILs biological activities [4,5] and physico-chemical properties [6,7] achieving reliable predictions and allowing an intelligent selection of further measurements in order to expand the explored experimental space.
The work presented here moves a step forward for conjugating efficiency and sustainability of ILs, presently a major issue of the scientific community.
References:
[1] Paternò, A.; D Anna, F.; Musumarra, G.; Noto, R.; Scirè, S., RSC Adv., 2014, 4, 23985.
[2] Paternò, A.; Bocci, G.; Goracci, L.; Musumarra, G.; Scirè, S., SAR QSAR Environ. Res., 2016, 27, 1.
[3] Paternò, A; D Anna, F.; Fortuna, C. G.; Musumarra, G., Tetrahedron, 2016, 72, 3282.
[4] Paternò, A.; Bocci, G.; Cruciani, G.; Fortuna, C. G.; Goracci, L.; Musumarra, G.; Scirè, S., SAR QSAR Environ. Res., 2016, 27, 221.
[5] Paternò, A.; Scirè, S.; Musumarra, G., Toxicol. Res., 2016, 5, 1090.
[6] Paternò, A.; Fiorenza, R.; Marullo, S.; Musumarra, G.; Scirè, S., RSC Adv., 2016, 6, 36085.
[7] Paternò, A.; Goracci, L.; Scirè, S.; Musumarra, G., ChemistryOpen, 2017, doi: 10.1002/open.201600119
Nanoconstructs Photoactivated with antimicrobial activity
No full textThe search of novel antibacterial treatment modalities designed to face problems of an- tibiotic Multi Drug Resistance (MDR) associated with the alarmingly low turnover of new clinically approved antibiotic drugs is one of the main challenges in biomedicine. In this frame, the achievement of tailored systems able to release therapeutic agents in a controlled fashion is one of the growing area in the burgeoning field of nanomedicine. Light represents the most elegant and non-invasive trigger to deliver bio-active compounds on demand at the target site with superb control of three main factors, site, timing and dosage, determin- ing for the therapeutic outcome. In addition, light triggering is biofriendly, provides fast reaction rates and offers the great benefit of not affecting physiological parameters such as temperature, pH and ionic strength, fundamental requisite for biomedical applications. Recent breakthroughs of nanotechnology offer the opportunity to characterize, manipulate and organize matter at the nanometer scale, controlling the size and shape of the result- ing nanomaterials and greatly improving the biocompatibility and the cellular uptake effi- ciency. This thesis focuses on the design and fabrication of light-activated nanoconstructs for the controlled delivery of unconventional therapeutics such as reactive oxygen and nitrogen species, and heat which, in contrast to conventional drugs, do not suffer MDR problems and display reduced systemic effects. A range of nanosystems able to generate individually, sequentially or simultaneously the above cytotoxic agents is reported and, in some case, their antibacterial activity is also investigated. This dissertation is divided in two sections: the first one regards nanomaterials, while the second focuses on molecular hybrid systems, all preceded by a brief in-troduction
Modelling the mind: studying the decisional processes by the means of trust on information sources
No full textIn every moment, the events that happen in our life put us in the condition to make a decision. Maybe this decision could refer to a not so much relevant task, so that it is relatively easy to decide, probably because each possible choice has not a great impact on our life: we are not going to take a risk (or there is a low level of risk), there is not a heavy possible lose that threatens us.
But there can be situations in which the choice we take can seriously have a great impact, and then require a bigger cognitive effort. Sometimes we have to take into account a risk factor; there could be the possibility to lose material goods or even to compromise our health itself. What to do in these risky situations? As it is easy to understand, in these situations the decisional process becomes heavier; identifying a correct choice or at least the best one is a critical task.
In order to make a decision, it is necessary a proper quantity of knowledge. The first thing to do is quite obvious: we try to use the knowledge we already have, using the one that represents our basic beliefs, the knowledge that we have about the world in which we live. It has been built and consolidated in time and it is available each time we need it. However, in many case our own knowledge is not enough for the task that we have to face in the real world. For instance we could have the necessity to make a decision in a context in which we are not competent, or maybe we do not have the possibility to evaluate properly the situation. Maybe we could find our self in a dynamic system, in which it is not so easy to make a forecast of how it will change.
Therefore in many situations that occur in our daily life it is necessary to ask someone/something else, to use knowledge that comes from external sources. However when we try to use information coming from an external source, we get into some complicated dynamic: it rises up some problems that it is necessary to face.
In this study we intend to understand which are the methodologies that allow using effectively external information sources for our internal decisional processes, with the aim of identifying a choice between a series of alternatives. In particular, we propose the use of the concept of trust applied to the information sources.
In order to do so, we first developed a theory about trust on information sources, starting from the classical model of trust already proposed in literature. The one of trust is the key concept that allows us to use information sources. Thanks to it, we are able to consider differently each source, understanding which are more trustworthy and then can be taken into account while reasoning and those which are not enough trustworthy that has to be treated differently (at least, they must have a lighter weight). Then trust becomes a weight to use towards information sources.
Then, by the means of simulative technologies we studied the practical aspect of this theory, applying these computational models to practical context. This allowed us to identify some interesting aspect both from the theoretical level and the practical level