Feeding the Gut Microbiome and Immune Maturation to Manage Weaned Piglets

This thesis reports five studies that may contribute to understand how weaning affects the immune and intestinal microbiota maturation of the piglet and proposes some possible nutritional strategies to attenuate its negative effects. The first study showed that weaning is associated in Payer’s patches with the activation of MHC response against class I antigens and that related to the stimulation to IFN-γ and showed, for the first time, that their blood at weaning remains dominated by immature blood cells. In the second study we tested if the use of a live vaccine against a conditionally but also genetically based intestinal disease, like PWD, could have an impact on the growth performance of pigs and their intestinal microbiota and if it could provide a model to test the response to nutritional strategies under conditions of an immune and intestinal stimulation for animals susceptible to ETEC type. In this study, we demonstrated how a vaccinal strain of F4/F18 E. coli can affect the gut microbial composition of piglets, regardless of their genetic susceptibility to ETEC infection. In the third study we evidenced how a nucleotide supplementation can favor the proliferation of jejunal Peyer patches and anticipate the maturation of the fecal microbiota. In the fourth study we reported how xylanase can favor the proliferation of Lactobacillus reuteri. Finally, we showed some first results on the muscles fiber development in fast- and slow-growing suckling pigs and the relationship with the intestinal microbiota. Taken together, the results presented in this thesis provide new insight about the interplay between the host-genetics, gut microbial composition, and host physiological status. Furthermore, it provides confirmation that the use of known genetic markers for ETEC F4 and F18 could represent a potential tool to stratify the animals in the trials both in healthy or challenge-based protocols.

Sulforaphane as a multifunctional neuroprotective molecule to prevent and slow down the progression of Alzheimer’s disease

Oxidative stress has been implicated in the pathogenesis of a number of diseases including neurodegenerative disorders, cancer, ischemia, etc. Alzheimer’s disease (AD) is histopathologically characterized by the presence of extracellular senile plaque (SP), predominantly consisting of fibrillar amyloid-peptide (Aβ), intracellular neurofibrillary tangles (NFTs), composed of hyperphosphorylated tau protein, and cell loss in the selected regions of the brain. However, the pathogenesis of AD remains largely unknown, but a number of hypothesis were proposed for AD mechanisms, which include: the amyloid cascade, excitotoxicity, oxidative stress and inflammation hypothesis, and all of them are based, to some extent on the role of A. Accumulated evidence indicates that the increased levels of ROS may act as important mediators of synaptic loss and eventually promote formation of neurofibrillary tangles and senile plaques. Therefore a vicious circle between ROS and Aaccumulation may accelerate progression of AD. For these reasons, growing attention has focused on oxidative mechanism of Atoxicity as well as the search for novel neuroprotective agents. A strategy to prevent the oxidative stress in neurons may be the use of chemopreventive agents as inducers of antioxidant and phase 2 enzymes. Sulforaphane (SF), derived from corresponding glucoraphanin, glucosinolate found in abundance in cruciferous vegetables, has recently gained attention as a potential neuroprotective compound inducer of antioxidant phase 2 enzymes. Consistent with this evidence, the study is aimed at identifying the SF ability to prevent and counteract the oxidative damage inducted by oligomers of Aβ (1-42) in terms of impairment in the intracellular redox state and cellular death in differentiated human neuroblastoma and microglia primary cultures. In addition we will evaluated the mechanism underlying the SF neuroprotection activity.

Fast and accurate numerical solutions in some problems of particle and radiation transport: synthetic acceleration for the method of short characteristics, Doppler-broadened scattering kernel, remote sensing of the cryosphere

The aim of this work is to present various aspects of numerical simulation of particle and radiation transport for industrial and environmental protection applications, to enable the analysis of complex physical processes in a fast, reliable, and efficient way. In the first part we deal with speed-up of numerical simulation of neutron transport for nuclear reactor core analysis. The convergence properties of the source iteration scheme of the Method of Characteristics applied to be heterogeneous structured geometries has been enhanced by means of Boundary Projection Acceleration, enabling the study of 2D and 3D geometries with transport theory without spatial homogenization. The computational performances have been verified with the C5G7 2D and 3D benchmarks, showing a sensible reduction of iterations and CPU time. The second part is devoted to the study of temperature-dependent elastic scattering of neutrons for heavy isotopes near to the thermal zone. A numerical computation of the Doppler convolution of the elastic scattering kernel based on the gas model is presented, for a general energy dependent cross section and scattering law in the center of mass system. The range of integration has been optimized employing a numerical cutoff, allowing a faster numerical evaluation of the convolution integral. Legendre moments of the transfer kernel are subsequently obtained by direct quadrature and a numerical analysis of the convergence is presented. In the third part we focus our attention to remote sensing applications of radiative transfer employed to investigate the Earth's cryosphere. The photon transport equation is applied to simulate reflectivity of glaciers varying the age of the layer of snow or ice, its thickness, the presence or not other underlying layers, the degree of dust included in the snow, creating a framework able to decipher spectral signals collected by orbiting detectors.

Seizure prediction and control in epilepsy

The first part of my thesis presents an overview of the different approaches used in the past two decades in the attempt to forecast epileptic seizure on the basis of intracranial and scalp EEG. Past research could reveal some value of linear and nonlinear algorithms to detect EEG features changing over different phases of the epileptic cycle. However, their exact value for seizure prediction, in terms of sensitivity and specificity, is still discussed and has to be evaluated. In particular, the monitored EEG features may fluctuate with the vigilance state and lead to false alarms. Recently, such a dependency on vigilance states has been reported for some seizure prediction methods, suggesting a reduced reliability. An additional factor limiting application and validation of most seizure-prediction techniques is their computational load. For the first time, the reliability of permutation entropy [PE] was verified in seizure prediction on scalp EEG data, contemporarily controlling for its dependency on different vigilance states. PE was recently introduced as an extremely fast and robust complexity measure for chaotic time series and thus suitable for online application even in portable systems. The capability of PE to distinguish between preictal and interictal state has been demonstrated using Receiver Operating Characteristics (ROC) analysis. Correlation analysis was used to assess dependency of PE on vigilance states. Scalp EEG-Data from two right temporal epileptic lobe (RTLE) patients and from one patient with right frontal lobe epilepsy were analysed. The last patient was included only in the correlation analysis, since no datasets including seizures have been available for him. The ROC analysis showed a good separability of interictal and preictal phases for both RTLE patients, suggesting that PE could be sensitive to EEG modifications, not visible on visual inspection, that might occur well in advance respect to the EEG and clinical onset of seizures. However, the simultaneous assessment of the changes in vigilance showed that: a) all seizures occurred in association with the transition of vigilance states; b) PE was sensitive in detecting different vigilance states, independently of seizure occurrences. Due to the limitations of the datasets, these results cannot rule out the capability of PE to detect preictal states. However, the good separability between pre- and interictal phases might depend exclusively on the coincidence of epileptic seizure onset with a transition from a state of low vigilance to a state of increased vigilance. The finding of a dependency of PE on vigilance state is an original finding, not reported in literature, and suggesting the possibility to classify vigilance states by means of PE in an authomatic and objectic way. The second part of my thesis provides the description of a novel behavioral task based on motor imagery skills, firstly introduced (Bruzzo et al. 2007), in order to study mental simulation of biological and non-biological movement in paranoid schizophrenics (PS). Immediately after the presentation of a real movement, participants had to imagine or re-enact the very same movement. By key release and key press respectively, participants had to indicate when they started and ended the mental simulation or the re-enactment, making it feasible to measure the duration of the simulated or re-enacted movements. The proportional error between duration of the re-enacted/simulated movement and the template movement were compared between different conditions, as well as between PS and healthy subjects. Results revealed a double dissociation between the mechanisms of mental simulation involved in biological and non-biologial movement simulation. While for PS were found large errors for simulation of biological movements, while being more acurate than healthy subjects during simulation of non-biological movements. Healthy subjects showed the opposite relationship, making errors during simulation of non-biological movements, but being most accurate during simulation of non-biological movements. However, the good timing precision during re-enactment of the movements in all conditions and in both groups of participants suggests that perception, memory and attention, as well as motor control processes were not affected. Based upon a long history of literature reporting the existence of psychotic episodes in epileptic patients, a longitudinal study, using a slightly modified behavioral paradigm, was carried out with two RTLE patients, one patient with idiopathic generalized epilepsy and one patient with extratemporal lobe epilepsy. Results provide strong evidence for a possibility to predict upcoming seizures in RTLE patients behaviorally. In the last part of the thesis it has been validated a behavioural strategy based on neurobiofeedback training, to voluntarily control seizures and to reduce there frequency. Three epileptic patients were included in this study. The biofeedback was based on monitoring of slow cortical potentials (SCPs) extracted online from scalp EEG. Patients were trained to produce positive shifts of SCPs. After a training phase patients were monitored for 6 months in order to validate the ability of the learned strategy to reduce seizure frequency. Two of the three refractory epileptic patients recruited for this study showed improvements in self-management and reduction of ictal episodes, even six months after the last training session.

Preventing worker’s musculoskeletal disorders with wearable inertial sensors: ergonomics and modelling of physical human-robot interactions

The most widespread work-related diseases are musculoskeletal disorders (MSD) caused by awkward postures and excessive effort to upper limb muscles during work operations. The use of wearable IMU sensors could monitor the workers constantly to prevent hazardous actions, thus diminishing work injuries. In this thesis, procedures are developed and tested for ergonomic analyses in a working environment, based on a commercial motion capture system (MoCap) made of 17 Inertial Measurement Units (IMUs). An IMU is usually made of a tri-axial gyroscope, a tri-axial accelerometer, and a tri-axial magnetometer that, through sensor fusion algorithms, estimates its attitude. Effective strategies for preventing MSD rely on various aspects: firstly, the accuracy of the IMU, depending on the chosen sensor and its calibration; secondly, the correct identification of the pose of each sensor on the worker’s body; thirdly, the chosen multibody model, which must consider both the accuracy and the computational burden, to provide results in real-time; finally, the model scaling law, which defines the possibility of a fast and accurate personalization of the multibody model geometry. Moreover, the MSD can be diminished using collaborative robots (cobots) as assisted devices for complex or heavy operations to relieve the worker's effort during repetitive tasks. All these aspects are considered to test and show the efficiency and usability of inertial MoCap systems for assessing ergonomics evaluation in real-time and implementing safety control strategies in collaborative robotics. Validation is performed with several experimental tests, both to test the proposed procedures and to compare the results of real-time multibody models developed in this thesis with the results from commercial software. As an additional result, the positive effects of using cobots as assisted devices for reducing human effort in repetitive industrial tasks are also shown, to demonstrate the potential of wearable electronics in on-field ergonomics analyses for industrial applications.

Reduced-order modelling, circuit-level design and SOI fabrication of microelectromechanical resonators

This thesis deals with two important research aspects concerning radio frequency (RF) microresonators and switches. First, a new approach for compact modeling and simulation of these devices is presented. Then, a combined process flow for their simultaneous fabrication on a SOI substrate is proposed. Compact models for microresonators and switches are extracted by applying mathematical model order reduction (MOR) to the devices finite element (FE) description in ANSYS c° . The behaviour of these devices includes forms of nonlinearities. However, an approximation in the creation of the FE model is introduced, which enables the use of linear model order reduction. Microresonators are modeled with the introduction of transducer elements, which allow for direct coupling of the electrical and mechanical domain. The coupled system element matrices are linearized around an operating point and reduced. The resulting macromodel is valid for small signal analysis around the bias point, such as harmonic pre-stressed analysis. This is extremely useful for characterizing the frequency response of resonators. Compact modelling of switches preserves the nonlinearity of the device behaviour. Nonlinear reduced order models are obtained by reducing the number of nonlinearities in the system and handling them as input to the system. In this way, the system can be reduced using linear MOR techniques and nonlinearities are introduced directly in the reduced order model. The reduction of the number of system nonlinearities implies the approximation of all distributed forces in the model with lumped forces. Both for microresonators and switches, a procedure for matrices extraction has been developed so that reduced order models include the effects of electrical and mechanical pre-stress. The extraction process is fast and can be done automatically from ANSYS binary files. The method has been applied for the simulation of several devices both at devices and circuit level. Simulation results have been compared with full model simulations, and, when available, experimental data. Reduced order models have proven to conserve the accuracy of finite element method and to give a good description of the overall device behaviour, despite the introduced approximations. In addition, simulation is very fast, both at device and circuit level. A combined process-flow for the integrated fabrication of microresonators and switches has been defined. For this purpose, two processes that are optimized for the independent fabrication of these devices are merged. The major advantage of this process is the possibility to create on-chip circuit blocks that include both microresonators and switches. An application is, for example, aswitched filter bank for wireless transceiver. The process for microresonators fabrication is characterized by the use of silicon on insulator (SOI) wafers and on a deep reactive ion etching (DRIE) step for the creation of the vibrating structures in single-crystal silicon and the use of a sacrificial oxide layer for the definition of resonator to electrode distance. The fabrication of switches is characterized by the use of two different conductive layers for the definition of the actuation electrodes and by the use of a photoresist as a sacrificial layer for the creation of the suspended structure. Both processes have a gold electroplating step, for the creation of the resonators electrodes, transmission lines and suspended structures. The combined process flow is designed such that it conserves the basic properties of the original processes. Neither the performance of the resonators nor the performance of the switches results affected by the simultaneous fabrication. Moreover, common fabrication steps are shared, which allows for cheaper and faster fabrication.

Design and Performance Evaluation of Network-on-Chip Communication Protocols and Architectures

The scale down of transistor technology allows microelectronics manufacturers such as Intel and IBM to build always more sophisticated systems on a single microchip. The classical interconnection solutions based on shared buses or direct connections between the modules of the chip are becoming obsolete as they struggle to sustain the increasing tight bandwidth and latency constraints that these systems demand. The most promising solution for the future chip interconnects are the Networks on Chip (NoC). NoCs are network composed by routers and channels used to inter- connect the different components installed on the single microchip. Examples of advanced processors based on NoC interconnects are the IBM Cell processor, composed by eight CPUs that is installed on the Sony Playstation III and the Intel Teraflops pro ject composed by 80 independent (simple) microprocessors. On chip integration is becoming popular not only in the Chip Multi Processor (CMP) research area but also in the wider and more heterogeneous world of Systems on Chip (SoC). SoC comprehend all the electronic devices that surround us such as cell-phones, smart-phones, house embedded systems, automotive systems, set-top boxes etc... SoC manufacturers such as ST Microelectronics , Samsung, Philips and also Universities such as Bologna University, M.I.T., Berkeley and more are all proposing proprietary frameworks based on NoC interconnects. These frameworks help engineers in the switch of design methodology and speed up the development of new NoC-based systems on chip. In this Thesis we propose an introduction of CMP and SoC interconnection networks. Then focusing on SoC systems we propose: • a detailed analysis based on simulation of the Spidergon NoC, a ST Microelectronics solution for SoC interconnects. The Spidergon NoC differs from many classical solutions inherited from the parallel computing world. Here we propose a detailed analysis of this NoC topology and routing algorithms. Furthermore we propose aEqualized a new routing algorithm designed to optimize the use of the resources of the network while also increasing its performance; • a methodology flow based on modified publicly available tools that combined can be used to design, model and analyze any kind of System on Chip; • a detailed analysis of a ST Microelectronics-proprietary transport-level protocol that the author of this Thesis helped developing; • a simulation-based comprehensive comparison of different network interface designs proposed by the author and the researchers at AST lab, in order to integrate shared-memory and message-passing based components on a single System on Chip; • a powerful and flexible solution to address the time closure exception issue in the design of synchronous Networks on Chip. Our solution is based on relay stations repeaters and allows to reduce the power and area demands of NoC interconnects while also reducing its buffer needs; • a solution to simplify the design of the NoC by also increasing their performance and reducing their power and area consumption. We propose to replace complex and slow virtual channel-based routers with multiple and flexible small Multi Plane ones. This solution allows us to reduce the area and power dissipation of any NoC while also increasing its performance especially when the resources are reduced. This Thesis has been written in collaboration with the Advanced System Technology laboratory in Grenoble France, and the Computer Science Department at Columbia University in the city of New York.

Molecular bases, pathogenic mechanisms and possible therapeutic approach in Leber's Hereditary Optic Neuropathy

Leber’s hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by a rapid loss of central vision and optic atrophy, due to the selective degeneration of retinal ganglion cells. The age of onset is around 20, and the degenerative process is fast and usually the second eye becomes affected in weeks or months. Even if this pathology is well known and has been well characterized, there are still open questions on its pathophysiology, such as the male prevalence, the incomplete penetrance and the tissue selectivity. This maternally inherited disease is caused by mutations in mitochondrial encoded genes of NADH ubiquinone oxidoreductase (complex I) of the respiratory chain. The 90% of LHON cases are caused by one of the three common mitochondrial DNA mutations (11778/ND4, 14484/ND6 and 3460/ND1) and the remaining 10% is caused by rare pathogenic mutations, reported in literature in one or few families. Moreover, there is also a small subset of patients reported with new putative pathogenic nucleotide changes, which awaits to be confirmed. We here clarify some molecular aspects of LHON, mainly the incomplete penetrance and the role of rare mtDNA mutations or variants on LHON expression, and attempt a possible therapeutic approach using the cybrids cell model. We generated novel structural models for mitochondrial encoded complex I subunits and a conservation analysis and pathogenicity prediction have been carried out for LHON reported mutations. This in-silico approach allowed us to locate LHON pathogenic mutations in defined and conserved protein domains and can be a useful tool in the analysis of novel mtDNA variants with unclear pathogenic/functional role. Four rare LHON pathogenic mutations have been identified, confirming that the ND1 and ND6 genes are mutational hot spots for LHON. All mutations were previously described at least once and we validated their pathogenic role, suggesting the need for their screening in LHON diagnostic protocols. Two novel mtDNA variants with a possible pathogenic role have been also identified in two independent branches of a large pedigree. Functional studies are necessary to define their contribution to LHON in this family. It also been demonstrated that the combination of mtDNA rare polymorphic variants is relevant in determining the maternal recurrence of myoclonus in unrelated LHON pedigrees. Thus, we suggest that particular mtDNA backgrounds and /or the presence of specific rare mutations may increase the pathogenic potential of the primary LHON mutations, thereby giving rise to the extraocular clinical features characteristic of the LHON “plus” phenotype. We identified the first molecular parameter that clearly discriminates LHON affected individuals from asymptomatic carriers, the mtDNA copy number. This provides a valuable mechanism for future investigations on variable penetrance in LHON. However, the increased mtDNA content in LHON individuals was not correlated to the functional polymorphism G1444A of PGC-1 alpha, the master regulator of mitochondrial biogenesis, but may be due to gene expression of genes involved in this signaling pathway, such as PGC-1 alpha/beta and Tfam. Future studies will be necessary to identify the biochemical effects of rare pathogenic mutations and to validate the novel candidate mutations here described, in terms of cellular bioenergetic characterization of these variants. Moreover, we were not able to induce mitochondrial biogenesis in cybrids cell lines using bezafibrate. However, other cell line models are available, such as fibroblasts harboring LHON mutations, or other approaches can be used to trigger the mitochondrial biogenesis.

The use of Ground Penetrating Radar and alternative geophysical techniques for assessing embankments and dykes safety

The research is part of a survey for the detection of the hydraulic and geotechnical conditions of river embankments funded by the Reno River Basin Regional Technical Service of the Region Emilia-Romagna. The hydraulic safety of the Reno River, one of the main rivers in North-Eastern Italy, is indeed of primary importance to the Emilia-Romagna regional administration. The large longitudinal extent of the banks (several hundreds of kilometres) has placed great interest in non-destructive geophysical methods, which, compared to other methods such as drilling, allow for the faster and often less expensive acquisition of high-resolution data. The present work aims to experience the Ground Penetrating Radar (GPR) for the detection of local non-homogeneities (mainly stratigraphic contacts, cavities and conduits) inside the Reno River and its tributaries embankments, taking into account supplementary data collected with traditional destructive tests (boreholes, cone penetration tests etc.). A comparison with non-destructive methodologies likewise electric resistivity tomography (ERT), Multi-channels Analysis of Surface Waves (MASW), FDEM induction, was also carried out in order to verify the usability of GPR and to provide integration of various geophysical methods in the process of regular maintenance and check of the embankments condition. The first part of this thesis is dedicated to the explanation of the state of art concerning the geographic, geomorphologic and geotechnical characteristics of Reno River and its tributaries embankments, as well as the description of some geophysical applications provided on embankments belonging to European and North-American Rivers, which were used as bibliographic basis for this thesis realisation. The second part is an overview of the geophysical methods that were employed for this research, (with a particular attention to the GPR), reporting also their theoretical basis and a deepening of some techniques of the geophysical data analysis and representation, when applied to river embankments. The successive chapters, following the main scope of this research that is to highlight advantages and drawbacks in the use of Ground Penetrating Radar applied to Reno River and its tributaries embankments, show the results obtained analyzing different cases that could yield the formation of weakness zones, which successively lead to the embankment failure. As advantages, a considerable velocity of acquisition and a spatial resolution of the obtained data, incomparable with respect to other methodologies, were recorded. With regard to the drawbacks, some factors, related to the attenuation losses of wave propagation, due to different content in clay, silt, and sand, as well as surface effects have significantly limited the correlation between GPR profiles and geotechnical information and therefore compromised the embankment safety assessment. Recapitulating, the Ground Penetrating Radar could represent a suitable tool for checking up river dike conditions, but its use has significantly limited by geometric and geotechnical characteristics of the Reno River and its tributaries levees. As a matter of facts, only the shallower part of the embankment was investigate, achieving also information just related to changes in electrical properties, without any numerical measurement. Furthermore, GPR application is ineffective for a preliminary assessment of embankment safety conditions, while for detailed campaigns at shallow depth, which aims to achieve immediate results with optimal precision, its usage is totally recommended. The cases where multidisciplinary approach was tested, reveal an optimal interconnection of the various geophysical methodologies employed, producing qualitative results concerning the preliminary phase (FDEM), assuring quantitative and high confidential description of the subsoil (ERT) and finally, providing fast and highly detailed analysis (GPR). Trying to furnish some recommendations for future researches, the simultaneous exploitation of many geophysical devices to assess safety conditions of river embankments is absolutely suggested, especially to face reliable flood event, when the entire extension of the embankments themselves must be investigated.

Controllo Vettoriale generalizzato per Macchine Elettriche Trifase

Nell’ambito della presente tesi verrà descritto un approccio generalizzato per il controllo delle macchine elettriche trifasi; la prima parte è incentrata nello sviluppo di una metodologia di modellizzazione generale, ossia in grado di descrivere, da un punto di vista matematico, il comportamento di una generica macchina elettrica, che possa quindi includere in sé stessa tutte le caratteristiche salienti che possano caratterizzare ogni specifica tipologia di macchina elettrica. Il passo successivo è quello di realizzare un algoritmo di controllo per macchine elettriche che si poggi sulla teoria generalizzata e che utilizzi per il proprio funzionamento quelle grandezze offerte dal modello unico delle macchine elettriche. La tipologia di controllo che è stata utilizzata è quella che comunemente viene definita come controllo ad orientamento di campo (FOC), per la quale sono stati individuati degli accorgimenti atti a migliorarne le prestazioni dinamiche e di controllo della coppia erogata. Per concludere verrà presentata una serie di prove sperimentali con lo scopo di mettere in risalto alcuni aspetti cruciali nel controllo delle macchine elettriche mediante un algoritmo ad orientamento di campo e soprattutto di verificare l’attendibilità dell’approccio generalizzato alle macchine elettriche trifasi. I risultati sperimentali confermano quindi l’applicabilità del metodo a diverse tipologie di macchine (asincrone e sincrone) e sono stati verificate nelle condizioni operative più critiche: bassa velocità, alta velocità bassi carichi, dinamica lenta e dinamica veloce.

Analytical methods for evaluating the quality and the genuineness of olive oils

This Ph.D. thesis focuses on the investigation of some chemical and sensorial analytical parameters linked to the quality and purity of different categories of oils obtained by olives: extra virgin olive oils, both those that are sold in the large retail trade (supermarkets and discounts) and those directly collected at some Italian mills, and lower-quality oils (refined, lampante and “repaso”). Concurrently with the adoption of traditional and well-known analytical procedures such as gas chromatography and high-performance liquid chromatography, I carried out a set-up of innovative, fast and environmentally-friend methods. For example, I developed some analytical approaches based on Fourier transform medium infrared spectroscopy (FT-MIR) and time domain reflectometry (TDR), coupled with a robust chemometric elaboration of the results. I investigated some other freshness and quality markers that are not included in official parameters (in Italian and European regulations): the adoption of such a full chemical and sensorial analytical plan allowed me to obtain interesting information about the degree of quality of the EVOOs, mostly within the Italian market. Here the range of quality of EVOOs resulted very wide, in terms of sensory attributes, price classes and chemical parameters. Thanks to the collaboration with other Italian and foreign research groups, I carried out several applicative studies, especially focusing on the shelf-life of oils obtained by olives and on the effects of thermal stresses on the quality of the products. I also studied some innovative technological treatments, such as the clarification by using inert gases, as an alternative to the traditional filtration. Moreover, during a three-and-a-half months research stay at the University of Applied Sciences in Zurich, I also carried out a study related to the application of statistical methods for the elaboration of sensory results, obtained thanks to the official Swiss Panel and to some consumer tests.

Chemical, biochemical and microbiological indicators to assess soil quality in temperate agro-ecosystems

Soil is a critically important component of the earth’s biosphere. Developing agricultural production systems able to conserve soil quality is essential to guarantee the current and future capacity of soil to provide goods and services. This study investigates the potential of microbial and biochemical parameters to be used as early and sensitive soil quality indicators. Their ability to differentiate plots under contrasting fertilization regimes is evaluated based also on their sensitivity to seasonal fluctuations of environmental conditions and on their relationship with soil chemical parameters. Further, the study addresses some of the critical methodological aspects of microplate-based fluorimetric enzyme assays, in order to optimize assay conditions and evaluate their suitability to be used as a toll to asses soil quality. The study was based on a long-term field experiment established in 1966 in the Po valley (Italy). The soil was cropped with maize (Z. mays L.) and winter wheat (T. aestivum L.) and received no organic fertilization, crop residue or manure, in combination with increasing levels of mineral N fertilizer. The soil microbiota responded to manure amendment increasing it biomass and activity and changing its community composition. Crop residue effect was much more limited. Mineral N fertilization stimulated crop residue mineralization, shifted microbial community composition and influenced N and P cycling enzyme activities. Seasonal fluctuations of environmental factors affected the soil microbiota. However microbial and biochemical parameters seasonality did not hamper the identification of fertilization-induced effects. Soil microbial community abundance, function and composition appeared to be strongly related to soil organic matter content and composition, confirming the close link existing between these soil quality indicators. Microplate-based fluorimetric enzyme assays showed potential to be used as fast and throughput toll to asses soil quality, but required proper optimization of the assay conditions for a precise estimation of enzymes maximum potential activity.

Peptidomimetic ligands for tuning integrin-mediated signalling: rational design, synthesis and theranostic applications

Integrins are α/β-heterodimeric transmembrane adhesion receptors that mediate cell-cell and cell-ECM interactions. Integrins are bidirectional signalling receptors that respond to external signals (“outside-in” signalling) and in parallel, transduce internal signals to the matrix (“inside-out” signalling), to regulate vital cellular functions including migration, survival, growth and differentiation. Therefore, dysregulation of these tightly regulated processes often results in uncontrolled integrin activation and abnormal tissue expression that is responsible for many diseases. Because of their important roles in physiological and pathological events, they represent a validated target for therapeutic and diagnostic purposes. The aim of the present Thesis was focused on the development of peptidic ligands for α4β1 and αvβ3 integrin subtypes, involved in inflammatory responses (leukocytes recruitment and extravasation) and cancer progression (angiogenesis, tumor growth, metastasis), respectively. Following the peptidomimetic strategy, we designed and synthesized a small library of linear and cyclic hybrid α/β-peptidomimetics based on the phenylureido-LDV scaffolds for the treatment of chronic inflammatory autoimmune diseases. In order to implement a fast and non-invasive diagnostic method for monitoring the course of the inflammatory processes, a flat glass-surface of dye-loaded Zeolite L-crystal nanoparticles was coated with bioactive α4β1-peptidomimetics to detect specific integrin-expressing cells as biomarkers of inflammatory diseases. Targeted drug delivery has been considered a promising alternative to overcome the pharmacokinetic limitations of conventional anticancer drugs. Thus, a novel Small-Molecule Drug Conjugate was synthesized by connecting the highly cytotoxic Cryptophycin to the tumor-targeting RGDfK-peptide through a protease-cleavable linker. Finally, in view to making the peptide synthesis more sustainable and greener, we developed an alternative method for peptide bonds formation employing solvent-free mechanochemistry and ultra-mild minimal solvent-grinding conditions in common, inexpensive laboratory equipment. To this purpose, standard amino acids, coupling agents and organic-green solvents were used in the presence of nanocrystalline hydroxyapatite as a reusable, bio-compatible inorganic basic catalyst.

Newly developed electrosynthesis of Layered Double Hydroxides: application to sensing, energy storage and conversion

Layered Double hydroxides (LDHs) have been widely studied for their plethora of fascinating features and applications. The potentiostatic electrodeposition of LDHs has been extensively applied in the literature as a fast and direct method to substitute classical chemical routes. However, it does not usually allow for a fine control of the M(II)/M(III) ratio in the synthesized material and it is not suitable for large anions intercalation. Therefore, in this work a novel protocol has been proposed with the aim to overcome all these constraints using a method based on potentiodynamic synthesis. LDHs of controlled composition were prepared using different molar ratios of the trivalent to bivalent cations in the electrolytic solution ranging from 1:1 to 1:4. Moreover, we were able to produce electrochemically LDHs intercalated with carbon nanomaterials for the first time. A one-step procedure which contemporaneously allows for the Ni/Al-LDH synthesis, the reduction of graphene oxide (GO) and its intercalation inside the structure has been developed. The synthesised materials have been applied in several fields of interest. First of all, LDHs with a ratio 3:1 were exploited, and displayed good performances as catalysts for 5-(hydroxymethyl)furfural electro-oxidation, thus suggesting to carry out further investigation for applications in the field of industrial catalysis. The same materials, but with different metals ratios, were tested as catalysts for Oxygen Evolution Reaction, obtaining results comparable to LDHs synthesised by the classical co-precipitation method and also a better activity with respect to LDHs obtained by the potentiostatic approach. The composite material based on LDH and reduced graphene oxide was employed to fabricate a cathode of a hybrid supercapacitor coupled with an activated carbon anode. We can thus conclude that, to date, the potentiodynamic method has the greatest potential for the rapid synthesis of reproducible films of Co and Ni-based LDHs with controlled composition.

Insights on epidemiology and control of Marek’s disease through traditional and novel molecular tools

Marek's disease (MD) is a contagious, lymphoproliferative and neuropathic disease of poultry caused by a ubiquitous lymphotropic and oncogenic virus, Gallid alphaherpesvirus 2 (GaHV-2). MD has been reported in all poultry-rearing countries and is among the viral diseases with the highest economic impact in the poultry industry worldwide, including Italy. MD has been also recognized as one of the leading causes of mortality in backyard poultry. The present doctoral thesis aimed at exploring Marek's disease virus molecular epidemiology in Italian commercial and backyard chicken flocks and, for the first time, in commercial turkeys affected by clinical MD. Molecular biology techniques targeting the full-length meq gene, the major GaHV-2 oncogene, were used to detect and characterize the circulating GaHV-2 strains searching for genetic markers of virulence. A final study focused on the development of rapid, sensitive, and species-specific loop-mediated isothermal amplification assays coupled with a lateral flow device readout for the detection of conventional and recombinant HVT-based vaccines is included in the thesis. HVT vaccines, currently used to protect chickens from MD, are referred to as "leaky", as they do not impede the infection, replication, and shedding of field GaHV-2: vaccinal and field viruses can coexist in the vaccinated host and molecular tests able to discriminate between GaHV-2 and HVT are required. These new simple, fast, and accurate tests for the monitoring of MD vaccination success in the field could be greatly beneficial for field veterinarians, small laboratories, and more broadly for resource-limited settings.