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Managing the Internet of Things based on its Social Structure
Get PDFSociety is moving towards an “always connected” paradigm, where the Internet user is shifting from persons to things, leading to the so called Internet of Things (IoT) scenario. The IoT vision integrates a large number of technologies and foresees to embody a variety of smart objects around us (such as sensors, actuators, smartphones, RFID, etc.) that, through unique addressing schemes and standard communication protocols, are able to interact with each Others and cooperate with their neighbors to reach common goals [2, 3]. IoT is a hot research topic, as
demonstrated by the increasing attention and the large worldwide investments devoted to it.
It is believed that the IoT will be composed of trillions of elements interacting in an extremely heterogeneous way in terms of requirements, behavior and capabilities; according to [4], by 2015 the RIFD devices alone will reach hundreds of billions. Unquestionably, the
IoT will pervade every aspect of our world and will have a huge impact in our everyday life: indeed, as stated by the US National Intelligence Council (NIC) [5], “by 2025 Internet nodes may reside in everyday things − food packages, furniture, paper documents, and more”.
Then, communications will not only involve persons but also things thus bringing about the IoT environment in which objects will have virtual counterparts on the Internet. Such virtual entities will produce and consume services, collaborate toward common goals and should be
integrated with all the other services.
One of the biggest challenges that the research community is facing right now is to be able to organize such an ocean of devices so that the discovery of objects and services is performed efficiently and in a scalable way. Recently, several attempts have been made to apply concepts
of social networking to the IoT. There are scientific evidences that a large number of individuals tied in a social network can provide far more accurate answers to complex problems than a single individual (or a small group of – even knowledgeable – individuals) [1]. The exploitation of such a principle, applied
to smart objects, has been widely investigated in Internet-related researches. Indeed, several
schemes have been proposed that use social networks to search Internet resources, to route
traffic, or to select effective policies for content distribution. The idea that the convergence of the “Internet of Things” and the “Social Networks”
worlds, which up to now were mostly kept separate by both scientific and industrial communities, is possible or even advisable is gaining momentum very quickly. This is due to the growing awareness that a “Social Internet of Things” (SIoT) paradigm carries with it many desirable
implications in a future world populated by objects permeating the everyday life of human beings.
Therefore, the goal of this thesis is to define a possible architecture for the SIoT, which includes the functionalities required to integrate things into a social network, and the needed strategies to help things to create their relationships in such a way that the resulting social network is navigable. Moreover, it focuses on the trustworthiness management, so that interaction
among objects that are friends can be done in a more reliable way and proposes a possible
implementation of a SIoT network. Since this thesis covers several aspects of the Social internet of Things, I will present the state of the art related to the specific research activities at the beginning of every Chapter. The
rest of the thesis is structured as follows.
In Chapter 1, I identify appropriate policies for the establishment and the management of social relationships between objects, describe a possible architecture for the IoT that includes the functionalities required to integrate things into a social network and analyze the characteristics
of the SIoT network structure by means of simulations.
Chapter 2 addresses the problem of the objects to manage a large number of friends, by analyzing possible strategies to drive the objects to select the appropriate links for the benefit of overall network navigability and to speed up the search of the services.
In Chapter 3, I focus on the problem of understanding how the information provided by members of the social IoT has to be processed so as to build a reliable system on the basis of the behavior of the objects and define two models for trustworthiness management starting from
the solutions proposed for P2P and social networks.
Chapter 4 presents an implementation of a SIoT platform and its major functionalities: how to register a new social object to the platform, how the system manages the creation of new relationships, and how the devices create groups of members with similar characteristics.
Finally, in Chapter 5, conclusions will be drawn regarding the effectiveness of the proposed
Introduction 3 algorithms, and some possible future works will be sketche
Secondary Metabolites from Otanthus maritimus, Stachys glutinosa and Withania somnifera: Isolation, Structure Elucidation and Interactions with Cannabinoid and Opioid Systems
Get PDFIn our continuous search for plant secondary metabolites that bind to CB and/or opioid receptors, we selected four extracts that showed interesting affinity versus the above mentioned receptors . In particular: the DCM extract obtained from the aerial parts of Stachys glutinosa (SGE) was able to bind with a good affinity both MOR and DOR with a Ki of 10.3 and 9 μg/mL, respectively while the DCM extract from the leaves of Otanthus maritimus (OME) showed good binding affinity to CB1 (Ki = 2.2 μg/mL) and CB2 (Ki = 1.3 μg/mL) and moderate affinity to MOR and DOR. The third was an alkaloid fraction obtained from the MeOH extract of the roots of Withania somnifera (WSAE) that displayed appreciable affinity versus DOR (Ki = 25.5 μg/mL), CB1 (Ki = 23.5 μg/mL), CB2 (Ki = 20.3 μg/mL) and GABAA (Ki = 14 μg/mL). The in toto MeOH extract (WSE) bound with very low affinity to CB and opioid receptors but displayed interesting affinity to GABAA receptors (Ki = 14 μg/mL) Based on this results this study, carried out in collaboration with the group of Dr. Stefania Ruiu of CNR-‐Institute of Translational Pharmacology of Cagliari, aimed to: 1. Isolate the secondary metabolites that were responsible of the observed binding affinity 2. Identify the compounds by spectrometric and spectroscopic methods 3. Evaluate the binding affinity of the isolated metabolites to opioid and cannabinoid receptors. 4. Evaluate the most potent and abundant compounds in antinociceptive experiments in mice. A total of 30 secondary metabolites were isolated from the extracts. Two semisynthetic derivatives were also prepared. The OME yielded two new alkylamides and one new neo-‐lignan , along with thirteen known compounds. Among the constituents identified, 1-‐[(2E,4E,8Z)-‐tetradecatrienoyl]piperidine was the most potent binder to both CB1 and CB2 receptors with a Ki value of 0.8 M and 0.16 M, respectively. The molecular modeling approaches applied in this study put in evidence, important requirements for the activity of this series of compounds and gives several hints for the design of optimized CB2 ligands. From the SGE one new neo-‐clerodane, 3,4α-‐epoxyroseostachenol along four known flavones (eupatilin, sideritoflavone, xanthomicrol, and 8-‐methoxycirsilineol) and one neo-‐clerodane diterpene (roseostachenone), were isolated. In order to find a structure-‐activity relationships, two metoxyflavones (5-‐demethyltangeretin, and tangeretin) were synthesized by methoxylation of xanthomicrol. Our results showed that xanthomicrol, the main constituent of S. glutinosa aerial parts (2% of the dried extract) is the principal responsible of the observed opioid binding affinities of the extract, with a Ki value of 0.825 μM to μ opioid receptor. Since the μ receptor is thought to be primarily responsible for the mediation of opioid anti-‐nociception, we evaluated the anti-‐ nociceptive activity of xanthomicrol in the tail flick test. Our data demonstrated that pretreatment of xanthomicrol inhibited morphine-‐induced anti-‐nociception in the tail flick test, suggesting an antagonistic effect at μ opioid receptor. As regards WSE and WSAE, the results of the binding assays (Table 10) for the μ, CB and GABAA receptors suggested a possible anti-‐nociceptive effect of W. somnifera. Starting from these preliminar data and from previous studies demonstrating that Withania somnifera prevented the development of tolerance to the analgesic effect of morphine,166 using behavioral appoaches we demonstrate for the first time the ability of WSE pre-‐treatment to prolong analgesia and to prevent the development of rebound hyperalgesia in mice treated with morphine
Studio della formazione di ammine biogene e di altri composti azotati negli alimenti
Get PDFThe aim of this thesis was the qualitative and quantitative determination of biogenic amines (BA) and amino acids (AA), in particular the essential AA, in different food matrices
typical of Sardinia (Italy). The study was focused on wines and table olives, which are potential source of biogenic amines due to their fermentation processes involved in their
production. The decision to follow this research field is based on the importance of having updated information to assess the actual risk from ingesting BA, produced by decarboxylation of AA by microorganisms. These molecules, in fact, have direct or indirect effects on the
human vascular and nervous system, especially in people who are sensitive to these substances or in people with specific diseases and/or subjected to particular therapies that affect the normal metabolism. From the legal standpoint, the legislation is developing and it is necessary to collect data in order to improve the control measures for food safety. First step of the doctorate project was to set up an analytical method of high sensitivity simultaneous detection and quantification of BA and AA in food. The method was developed using selective derivatisation with dansyl chloride and HPLC with fluorescence detection and chromatographic separation of 36 compounds, 13 BA and 22 AA, ammonium ion was
successfully achieved. BA and AA were dosed using calibration curves built with the internal
standard method (norvaline). This method was validated according to ICH Topic Q 2 (R1)
1995 guidelines with the determination of a linearity range, r2, limit of detection (LOD), limit
of quantification (LOQ), intra and inter-day repeatability, and recovery.
In cooperation with several local vineries, a survey on BA and AA amount in Cannonau, Vermentino, Carignano e Vernaccia wines, the four most typical “Controlled
Designation of Origin” wines from Sardinia was performed. Sixty-one samples were analyzed, and 33 compounds (between BA and amino acids AA) were identified and quantified in the
wines analyzed. Carignano wine is particularly rich in BA compounds, while Vermentino wine has a concentration of BA lower than other wine analyzed. Putrescine, histamine and
tyramine are the BA found in higher concentration, but usually their amount is lower than 10 mg/L. -Aminobutyric acid is very concentrate in Vermentino wine, with an average value of 130.3±44.8 mg/L. About AA compounds, the highest total concentration is in Vermentino
wine, and proline is always the most representative AA.
Subsequently, a trial has been set in order to investigate the production of biogenic amines during the winemaking fermentation processes. The experiment was carried out in
collaboration with the Agris (Sardinian Regional Agency for Agricultural Research) on three types of characteristic wines of Sardinia: Cannonau, Vermentino and Moscato. The musts of Cannonau, Vermentino and Moscato were treated with different strains of yeast and bacteria
starter, and the evolution of the concentration of BA and AA (especially the essential AA) was monitored. Comparing the data obtained, it was observed that the three types of wine at the end of fermentation have interesting differences. It can be noted that the wine Cannonau is
particularly rich in nitrogen compounds compared to the two white wines, probably because of the malo-lactic fermentation that does not take place in the other two wines. The Vermentino and Moscato are more similar to each other. In general, it was observed that the
choice of starter turns out to be of significant impact in the formation of BA, though not all of the starter can make a difference. Furthermore, neither worrying values of histamine nor of tyramine were observed.
Finally, an experimentation regarding the table olives, a fermented product very popular in all Mediterranean area, was developed. Sampling was carried out on a typical Sardinian olive cultivar, the ‘Nera di Gonnos’, and transformation followed the traditional natural
fermentation. The HPLC-FLD method used for the wines was modified and validated for the olives. The analyses were conducted during the different steps of fermentation and after one year. Fifteen compounds, between AA and AB, were identified. The obtained data revealed that during the production process there is an increase of formation of nitrogen compounds in general, but the presence in table olives of histamine and tyramine is significantly below
the values considered dangerous.
In conclusion, a useful, reliable and easily applied HPLC-FLD method to monitor and safeguard the quality and safety of food products was developed. The traditional products
from Sardinia showed a general good quality. It would be interesting also to extend the research by selecting and testing other microbial strains in order to obtain products with a lower content of BA and higher essential AA or other useful AA, such as Arg, that have important beneficial effects, yielding products with high qualit
Differential effects of mouse APOBEC3 after incorporation into murine leukemia viruses
Get PDFAPOBEC3 proteins are cytidine deaminases that are potent inhibitors of retrovirus replication. These restriction factors induce G→A hypermutation as a result of deamination of cytidine in the single stranded transcripts generated by reverse transcription during replication. Mouse APOBEC3 (mA3) effectively inhibits the replication of endogenous retroelements whereas most exogenous murine leukemia viruses (MuLV) are largely resistant to the action(s) of mA3. However, several studies have reported significant inhibition of infectivity by virion-associated mA3 that did not appear to be the result of G→A hypermutation. In this report the influence of different levels of virion-associated mA3 on the exogenous MuLV, CasFrKP was examined. A correlation was observed between the level of incorporated mA3, the virion specific infectivity, the virion reverse transcriptase (RT) activity and the mutation frequency. Although G→A hypermutation of CasFrKP was not observed, the frequency of other transition mutations was significantly increased. G→A mutations induced by mA3 have been reported to exhibit a strong consensus of two bases flanking the mutation. No strong consensus was observed for mA3-induced mutations of CasFrKP suggesting a general decrease in the fidelity of the RT. The results of this study strongly suggest an interaction between mA3 and the RT of CasFrKP leading to a loss of activity as well as fidelity of the polymerase that ultimately results in a significant loss of infectivity.
In contrast to CasFrKP, AKV, an ecotropic MuLV isolated from AKR mice, has been reported to undergo hypermutation mediated by mA3. In this report we also confirm that AKV does undergo G→A hypermutation upon infection of 3T3 cells, however hypermutation is not augmented in viruses that have incorporated HA-tagged mA3. Furthermore, the observed G→A transition mutations are not randomly distributed in that multiple mutations frequently occur in a single transcript. These observations suggest that the G→A mutations are the result of the incorporation of an unknown restriction factor in only a portion of the released virions
On the usage of the curvature for the comparison of planar curves
Get PDFGiven two curves, on the plane or in space, or surfaces, looking for a deformation from one into another such that the transformation is gradual and continuous is
an open and interesting problem both from a theoretical stand point and for the applications that can be envisaged. In particular, if the two starting shapes have
some particular features, we expect that also the intermediate ones preserve the same characteristics. This thesis focuses on planar closed curves, aiming to
find deformations between two planar closed curves, preserving the closeness.
Our approach is treating curves in the perspective of Differential Geometry, that is represented by parameterizations. We show how the simple idea of
linearly interpolating between the two parameterizations is too much dependent on the mutual position of the curves, implicit in the parameterizations. This suggested us to consider a deformation based on intrinsic properties of curves, in particular we took in account the curvature. The fundamental theorem of planar curves states that, given the signed curvature function with respect to arc length, it is possible to reconstruct the curve from it up to rigid motions which preserve the orientation. Motivated by these observations we linearly interpolate the curvature of source and target curves, parameterized with respect
to the arc length, and we reconstruct the corresponding intermediate curves.
Unfortunately, the curvature interpolation not always leads to closed curves.
We overwhelmed this limitations replacing each intermediate open curve with the closed curve as close as possible to the open one measuring the same length.
To do this we need to define an appropriate distance between curves. A distance based on the mutual position of the curves and dependent on their particular parameterizations is not feasible for our purposes, so as measure of distance
between two curves we consider the distance between their curvatures. This paradigm shift leads to find the curve with the curvature as close as possible to the curvature of the open, interpolated, one. This decision is supported by
the proof that there is a link between close curvatures and close curves, or to be more precise, that the distance between curvatures gives a bound for the distance between corresponding curves with a particular mutual position, where distances are computed with appropriate metric. We also show that solving this problem in the smooth setting is very difficult since it is not a classical variational problem, so we propose a simple example where we try to solve the variational problem in the smooth setting and then we conclude giving an approximated solution for the general case
Modellistica computazionale molecolare di complessi proteici con applicazioni a Sclerosi Multipla, Sindrome Fibromialgica e Funzionamento Muscolare
Get PDFThe main objective of this work is to show that clinical individual information and
experimental fndings on biological systems can be effectively integrated by
computational modelling at an atomistic scale, to provide elucidation of, support to
or proposal of functional mechanisms.
The complexity of the leaving systems requires specifc approaches for specifc
diseases. In this work, I focused on Multiple Sclerosis and the antigen presentation
step in the adaptive immune system response as a possible contribution to disease
onset and progression, pinpointing a functional mimicry in the self and nonself
peptide recognition operated by the predisposing HLA alleles. The Fibromyalgic
Syndrome is also discussed and a potential link between diet-derived PAF-like lipids
and the activation of a pain molecular pathway mediated by PAFR receptor is
proposed. Finally the interaction of Calcium ions and the CASQ protein – relevant
for muscle contractions – is analysed, and a model of the ion binding mechanisms
and protein polymerization/de-polymerization is discussed.
The investigation instrument adopted is the Molecular Dynamics Modeling, and the
developed protocols for the preparation, simulation and analyses of each biological
system are provided.
The therapeutical perspectives of the fndings here presented are related to the
design of i) peptides able to interfere with the antigen presentation mechanism and
modulate autoimmune response; ii) an individual risk model for multiple sclerosis
patients; iii) molecules able to interfere with the PAFR and modulate pain molecular
signalling; iv) biomarkers for diagnosis support and clinical tests for the
Fibrormyalgic Syndrome; v) molecules able to interfere with the Calcium and CASQ
interaction, able to modulate heart beat; vi) personalised diet modulating the
introduction of fat possibly contributing to Fibromyalgy
Decentralisation and Poverty Alleviation in Zambia: Achievable Goal or Deceptive Promise?
Get PDFSince the 1990s, decentralisation has acquired increasing popularity among governments and aid agencies. Today, it is hard to find a country that has not undergone the reform of its local government system. Since 2000, decentralisation has been heavily promoted by donors as an important tool to tackle extreme poverty and promote development. Despite this popularity, the pro-poor effects of decentralisation are not supported by unarguable evidence and the literature available offers, at best, a mixed picture. This study tries to contribute at filling this gap, using as case study a country, Zambia, which has been almost neglected by the literature on decentralisation
An Approach Based on Complex Network to Analyse and Optimise Smart Grid
Get PDFIn the last decades, a lot of efforts and studies have been committed to environment protection.
However, it is only during the last few years that this need has become even more compelling
due to our consumerist lifestyle, which produces pollution and is based on the exploitation of
limited natural resources. We have been witnessed to some important green initiatives such as
recycling, reafforestation, traffic blocks and energy saving measures but none of these can be
considered decisive. For this reason, lately, most of researches are focused on a topic that could
actually make the difference: Smart Grids.
The term Smart Grid indicates a futuristic concept for an utility grid where the conventional
services are coupled with ICT resources in order to manage production and consumption pro-
cess in detail, avoiding waste and service interruption. This topic has gained more and more
visibility thanks to the numerous dedicate conferences organized all around the world. Various
organizations, including Enel in Italy, began their own smart grid project, showing great inter-
est especially for the possibility to achieve a better integration with renewable. Since a smart
grid can be considered as the result of a combination between engineering and computer science
competences, we can list a lot of different research lines and opened challenges. After an initial
period of documentation, I decided to focus my PhD on the analysis of our regional power grid
in Sardinia. We had spent the first months collecting data about energy production and con-
sumption from Enel and Terna, and then we used them to build a model which became the test
bench for future tests. Using a specific tool for complex analysis, has been possible to depict
the main characteristics of the system and, through a centrality index, we spotted the zones
considered more susceptible to failures. This approach may results peculiar to some, since the
term complex networks usually refers to social, biological or, in general, networks characterized
by a huge number of nodes and arcs. In these architectures, the bounds between nodes are more
important rather than their topological structure that, instead, is considered fundamental in
power grids. However, we eventually find out that also smart grids are suitable to be analysed
through complex techniques. Indeed, according to Kirchhoff's and Ohm's laws, which govern
energy distribution among the areas of the grid, we can spot some analogies of their operation
through the study of the patterns and clusters that naturally exists in the model. Results ob-
tained by this first step of analysis, have been used as starting point for some stress tests on
the grid, in order to evaluate its level of tolerance to failures. Once spotted the weak nodes,
we have used them to create several scenarios where some failures and their consequences are
represented. Using an optimization algorithm we studied how the performances change under
harsh conditions and how the distribution
ows must be reorganized to heal grid connections,
making them operational. Changes in performance are registered as the difference between costs
calculated as the objective functions of scenarios. Moreover, we use other parameters such as
redundancy and arcs usage to evaluate the state of the grid after each failure.
In order to make the experiments as more realistic as possible, we faced the problem of
choosing the best metric for transmission cost, among the ones proposed in literature. We
eventually decided to use a novel metric that we called power loss defined from technical data
retrieved by Terna. It can be considered original, since it is created using physical parameters of
the cable beyond the classic voltages and current
Interactive Spaces Natural interfaces supporting gestures and manipulations in interactive spaces
Get PDFThis doctoral dissertation focuses on the development of interactive spaces through the use of
natural interfaces based on gestures and manipulative actions. In the real world people use their
senses to perceive the external environment and they use manipulations and gestures to
explore the world around them, communicate and interact with other individuals. From this
perspective the use of natural interfaces that exploit the human sensorial and explorative
abilities helps filling the gap between physical and digital world.
In the first part of this thesis we describe the work made for improving interfaces and devices for
tangible, multi touch and free hand interactions. The idea is to design devices able to work also
in uncontrolled environments, and in situations where control is mostly of the physical type
where even the less experienced users can express their manipulative exploration and gesture
communication abilities.
We also analyze how it can be possible to mix these techniques to create an interactive space,
specifically designed for teamwork where the natural interfaces are distributed in order to
encourage collaboration.
We then give some examples of how these interactive scenarios can host various types of
applications facilitating, for instance, the exploration of 3D models, the enjoyment of multimedia
contents and social interaction.
Finally we discuss our results and put them in a wider context, focusing our attention particularly
on how the proposed interfaces actually improve people’s lives and activities and the interactive
spaces become a place of aggregation where we can pursue objectives that are both personal
and shared with others
Edizione critica e commentata del canzoniere di Domizio Brocardo(circa 1380-circa 1457)
Get PDFThis work is a critical and commented edition of Domizio Brocardo’s canzoniere, entitled Vulgaria fragmenta by the model of Francesco Petrarca’s Rerum vulgarium fragmenta, the principal reference point for Brocardo’s poetry (for example, in the 132 poems of the Vulgaria fragmenta we find only the metrical forms of Petrarca’s canzoniere, and almost in the same proportions). He was born around 1380, very probably in Padua, and he died around 1457, likely always in Padua where he lived nearly for all his life. The edition is conducted in accordance with the method of Lachmann; the commentary investigates the metre, the sources and the success of each text. The analysis is extended also to the attributable poems and to the doubtful ones