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Empowering Online Idea Management for Civic Engagement with Public Displays and Social Networking Services
No full textIdea Management (IM) is the process of requesting, collecting, selecting and evaluating ideas to develop new and innovative products, services or regulations, or to improve existing ones. The process is supported by dedicated Idea Management systems (IMS), which lets people propose ideas, as well as rate and place comments on other users’ suggestions. When used in the civic domain, IM serves as a tool to engage citizens in processes of innovation of public services, laws, and regulations. A key ingredient in the success of IM is the community of participants. The larger the community, the more diverse views are likely to appear and diversity of views increases the chances of discovering valuable ideas that can lead to innovations. However, having a large number of people participating in IMS is a hard challenge; it requires an understanding of the people and their needs and designing the technology to match these characteristics. In this thesis, we aim at involving the society at large into IM processes. Achieving this ambitious goal requires integrating IMS with people’s everyday life tools and spaces of participation. We understand that tools for civic engagement should engage people on their own terms and should be readily available. We meet these requirements by proposing an approach that integrates IMS into common physical and virtual spaces of participation enabling people to participate in IM using ordinary tools and without having to step outside their daily habits. In a systematic and extensive study of the literature about technologies used to foster civic engagement in innovation processes, we found that the choice of technology and its “situated- ness” is essential in granting ease of public access and promoting inclusive processes of civic engagement. We also discovered that civic engagement technologies still have room to improve their use of multiple channels of participation. In this regard, we saw social networking sites such as Facebook and Twitter as having a strong potential to lower participation barriers and engage citizens, considering how pervasive these sites are today as daily tools.
We show how the lessons learned can be applied in practice by presenting two solutions to increase participation in IMS. The first solution is a platform that extends IMS by integrating them into displays located in public spaces. From this experience, we found that taking the right instruments to where people actually are is important to address specific inequalities regarding access to technology. We also saw that the display represented for citizens not only an opportunity to make their voice being heard but also an occasion for socialization. The second solution is a model and tool that empower IMS through Facebook services. Here we found that the integration with Facebook facilitated participation by reducing the friction related to getting informed and involved in IM. Also, the participants reported that the familiarity and easy to use of Facebook features represented an advantage for participation. We informed the design of both solutions with large- and medium-scale data analysis studies on the behavior (individual and collective), practices, and motivation factors of IM communities’ participants
Analysis and development of nonlinear Finite Elements for modelling steel structures at ambient and elevated temperature
Get PDFThis thesis work aims to successively analyze and develop "ex novo" problems concerning the use of finite elements for the analysis of issues characterized by high plasticity, geometrical and material nonlinearity, large displacements and rotations; all combined with the effect of temperature on the material mechanical properties. The ultimate objective of the work is the analysis and development of nonlinear Finite Elements devoted to the modelling of steel structures at ambient and elevated temperature.
Three different experiences will be analyzed in this elaborate; each of them characterised by specific issues that may be involved in the analysis via finite element
method of steel structures at ambient and elevated temperature. At the same time innovative aspects that are related, for example, to the particular typology of the
analyzed case study (first case) or in the methodology used in the treatment of the problem (second and third case) are investigated. The thesis structure chronologically retraces this path and the results and the experience gained from each of them were exploited to ultimately implement a thermomechanical finite element that is expression of all the tackled problems. The thesis consists of a collection of three papers that have been published or submitted on each of the investigated topics.
In detail:
- In the first paper, a commercial finite-element code, of the type "multipurpose", such as ANSYS has been used for the analysis of innovative cold-formed, laterallyrestrained steel rectangular hollow flange beams subjected to monotonic bending test. The numerical analysis has been carried out by means of the direct comparison with experimental tests on real scale specimens; that has allowed the detection of some phenomenological problems that have been included in the model calibration. From a numerical point of view, this work has at first allowed to deeply investigate the plastic problem by means, for example, the appropriate identification of the constitutive laws for the material, the correct choice of hardening law and yield surface, and their impact on the model. The local buckling problem typical of these profiles has been evaluated, through the use of shell elements. Furthermore, the effect of the global and local imperfections, which have been introduced in the model with different amplitudes, has been deeply investigated by evaluating their effect on the ultimate load. The calibration of the model finally allowed to perform a series of parametric analyses in order to extend the results to an extended range of profiles, characterized by different slenderness.
- In the second paper, the thermal problem has been introduced with the support of a finite element software, designed specifically for thermomechanical analysis (SAFIR).
The case study is, in this case, based on a multi-storey steel-concrete composite open car park subjected to localized fire of vehicles. With this study, not only the plastic problem has been analyzed but also phenomena such as the effect of high geometrical nonlinearity and large displacements on the structure in addition to the temperature effect on materials mechanical properties. The case study has been used to evaluate the assumptions and the issues that arise when developing an innovative integrated
modelling methodology between a computational fluid dynamics (CFD) software applied to compartment fires and a finite element (FE) software applied to structural systems. Particular emphasis has been given to the weak coupling approach developed between the CFD code fire dynamics simulator (FDS) and the FE software SAFIR.
- In the third and last paper all the experiences obtained from the previous works have been focused on the implementation, inside the MATLAB environment, of a thermomechanical beam finite element based on the co-rotational beam theory for the analysis of two-dimensional frames heated under high temperature and subjected to plastic deformation and to the effect of geometrical nonlinearity. The finite element is mainly aimed at the study of steel structures, with double-symmetrical profiles such as IPE or HE cross sections, and could then be used as a modelling tool for typical frames subjected to thermal actions. The element implements both Euler-Bernoulli and Timoshenko beam theories and can analyse slender to moderately stocky structures. A co-rotational formulation was used for describing the beam kinematic. The degradation of the steel mechanical properties at high temperature according to the Eurocode 1993-1-2 was considered by integrating the material constitutive law based on a
predetermined temperature field in the cross section. An improved displacement predictor for estimating the displacement field at the beginning of each time step was successfully implemented and allowed to significantly decrease the computational time. Furthermore, advanced path-following methods that detect secondary equilibrium
paths owing to instability occurrence were implemented in order to analyse the elasticplastic post-buckling behaviour of compressed steel elements at high temperature without the need of introducing geometrical imperfections. In order to show the potential of the developed finite element by highlighting the practical implications, a parametric analysis was performed to show whether the element could reproduce the EN1993-1-2 buckling curve. Validation against experimental and numerical data obtained with commercial software like ABAQUS and SAFIR is thoroughly shown in
the paper
Audiotactile interactions in the perception of duration
Get PDFThe following thesis project investigated the interactions between audition and touch in the perception of temporal duration. As will be seen throughout the thesis, different variables were explored to further understand these modalities interactions. Chapter 1 provides a review of the state of the art of multisensory integration, with an emphasis on studies addressing audiotactile interactions in
perception. Chapter 2 offers an initial experimental exploration of the interactions between audition and touch, in a duration discrimination paradigm. The next chapters are dedicated to explore how different variables that have shown to play a key role in multisensory integration, affect audiotactile interactions in the perception of duration. For example, Chapter 3 describes a study that explored
whether the intensities of the modalities of audition and touch affect their interaction in the perception of duration, allowing a further understanding of this
particular modality interaction. Chapter 4 illustrates a study of how the spatial location of auditory and tactile stimuli affects their interaction in the same duration perception task employed in previous chapters. Chapter 5 presents an empirical demonstration that emerged from an interest to investigate how different spatial frames of reference affect tactile duration discrimination. Chapter 6
provides a description of an experiment that tested how the senses of audition, vision and touch interact with one another in the perception of duration, in an interest to find out the hierarchies between these senses when perceiving duration. A further question relating the nature or extent of the modulation of the auditory modality over the perception of tactile duration was addressed in Chapter 7. In this chapter, a description of an experiment testing possible elongation effects of the auditory modality over the tactile one in duration perception is provided. Chapter
8 offers a general discussion of the main findings described along the following thesis project
La riscoperta della poesia antica italiana nei compositori del primo Novecento in Italia. Dalla generazione dell'Ottanta a Luigi Dallapiccola
Get PDFThe main purpose of this research was to study the motivations and requirements of a group of Italian composers, born around 1880, and for this chronological coincidence defined by Massimo Mila, as the composers of « The generation of the eighties» to use the lyrics of ancient Italian poetries for some of their operas.
It was a path of investigation taking into account many factors, in particular the interweaving of artistic and literary interests and the cultural historical complexity of the context of the late nineteenth and early twentieth centuries. Fundamental in the first place was the need to set up chronological indicative terms of the change, in fact of the real breakthrough determined at European level by the general crisis of positivism reflected in various ways in Italy in the form of a strong reaction to Verismo in literature and to Melodrama specifically within the music.
One of the first important aspect that we focused on in the present work was the fact that there were composers creating not only pieces made for the theater, but also symphonic and instrumental compositions. We proceeded to emphasize the reaction to melodrama expressed by the two most innovative composers of the Generation of the 80s: Casella, Malipiero and Pizzetti and in the In the third part, a great emphasis was given to two composers, Malipiero and Dallapiccola, who strived strongly for musical renewal, whose fundamental part was the reintroducing of the ancient.
In fact, initiating with the analysis of the dynamics of the cultural context of the late nineteenth and early twentieth centuries the brink of the Second World War has been reached. In conclusion, it was found that the desire to create something new even in the terms of music and its literary element has been conditioned by many factors, among which the strong willingness to depart from the nineteenth-century melodrama must be mentioned in the first place. The explanation of the revaluation of the texts of ancient Italian poetry by the composers of the early twentieth century is conditioned by numerous factors affected by the social, economic, cultural and historical aspects
Automatic Techniques for the Synthesis and Assisted Deployment of Security Policies in Workflow-based Applications
No full textWorkflows specify a collection of tasks that must be executed under the responsibility or supervision of human users. Workflow management systems and workflow-driven applications need to enforce security policies in the form of access control, specifying which users can execute which tasks, and authorization constraints, such as Separation/Binding of Duty, further restricting the execution of tasks at run-time. Enforcing these policies is crucial to avoid frauds and malicious use, but it may lead to situations where a workflow instance cannot be completed without the violation of the policy. The Workflow Satisfiability Problem (WSP) asks whether there exists an assignment of users to tasks in a workflow such that every task is executed and the policy is not violated. The run-time version of this problem amounts to answering user requests to execute tasks positively if the policy is respected and the workflow instance is guaranteed to terminate. The WSP is inherently hard, but solutions to this problem have a practical application in reconciling business compliance (stating that workflow instances should follow the specified policies) and business continuity (stating that workflow instances should be deadlock-free). Related problems, such as finding execution scenarios that not only satisfy a workflow but also satisfy other properties (e.g., that a workflow instance is still satisfiable even in the absence of users), can be solved at deployment-time to help users design policies and reuse available workflow models.
The main contributions of this thesis are three:
1. We present a technique to synthesize monitors capable of solving the run-time version of the WSP, i.e., capable of answering user requests to execute tasks in such a way that the policy is not violated and the workflow instance is guaranteed to terminate. The technique is extended to modular workflow specifications, using components and gluing assertions. This allows us to compose synthesized monitors, reuse workflow models, and synthesize monitors for large models.
2. We introduce and present techniques to solve a new class of problems called Scenario Finding Problems, i.e., finding execution scenarios that satisfy properties of interest to users. Solutions to these problems can assist customers during the deployment of reusable workflow models with custom authorization policies.
3. We implement the proposed techniques in two tools. Cerberus integrates monitor synthesis, scenario finding, and run-time enforcement into workflow management systems. Aegis recovers workflow models from web applications using process mining, synthesizes monitors, and invokes them at run-time by using a reverse proxy. An extensive experimental evaluation shows the practical applicability of the proposed approaches on realistic and synthetic (for scalability) problem instances
The microbiota-gut-brain axis: characterization of the gut microbiota in neurological disorders
No full textThe human gut microbiota plays a crucial role in the functioning of the gastrointestinal tract and its alteration can lead to gastrointestinal abnormalities and inflammation. Additionally, the gut microbiota modulates central nervous system (CNS) activities affecting several aspect of host physiology. Motivated by the increasing evidences of the role of the gut microbiota in the complex set of interactions connecting the gut and the CNS, known as gut-brain axis, in this Ph.D. thesis we asked whether the gastrointestinal abnormalities and inflammation commonly associated with neurological disorders such as Rett syndrome (RTT) and Autism could be related to alterations of the bacterial and fungal intestinal microbiota.
First, since only few reports have explored the fungal component of the gut microbiota in health and disease, we characterized the gut mycobiota in a cohort of healthy individuals, in order to reduce the gap of knowledge concerning factors influencing the intestinal microbial communities. Next, we compared the gut microbiota of three cohorts of healthy, RTT and autistic subjects to investigate if these neurological disorders harbour alterations of the gut microbiota. Culture-based and metataxonomics analysis of the faecal fungal populations of healthy volunteers revealed that the gut mycobiota differs in function of individuals’ life stage in a gender-related fashion. Different fungal species were isolated showing phenotypic adaptation to the intestinal environment. High frequency of azoles resistance was also found, with potential clinical significance.
It was further observed that autistic subjects are characterized by a reduced incidence of Bacteroidetes and that Collinsella, Corynebacterium, Dorea and Lactobacillus were the taxa predominating in the gut microbiota of autistic subjects. Constipation has been associated with different bacterial patterns in autistic and neurotypical subjects, with constipated autistic individuals characterized by higher levels of Escherichia/Shigella and Clostridium cluster XVIII than constipated neurotypical subjects. RTT is a neurological disorder caused by loss-of-function mutations of MeCP2 and it is commonly associated with gastrointestinal dysfunctions and constipation. We showed that RTT subjects harbour bacterial and fungal microbiota altered from those of healthy controls, with a reduced microbial richness and dominated by Bifidobacterium, different Clostridia and Candida. The alterations of the gut microbiota observed did not depend on the constipation status of RTT subjects while this microbiota produced altered SCFAs profiles potentially contributing to the constipation itself. Phenotypical and immunological characterizations of faecal fungal isolates from RTT subjects showed Candida parapsilosis as the most abundant species isolated in RTT, genetically unrelated to healthy controls’ isolates and with elevated resistance to azoles. Furthermore these isolates induced high levels of IL-10 suggesting increased tolerance and persistence within the host. Finally, the importance of multiple sequence alignment (MSA) accuracy in microbiome research was investigated comparing three implementations of the widely used NAST algorithm. By now, different implementations of NAST have been developed but no one tested the performances and the accuracy of the MSAs generated with these implementations. We showed that micca, a new bioinformatics pipeline for metataxonomics data improves the quality of NAST alignments by using a fast and memory efficient reimplementation of the NAST algorithm
Disentangling the representations of object shape and object category in the brain: the animate-inanimate distinction
No full textObjects belonging to different categories elicit reliably different response patterns in human ventral temporal cortex, with the most prominent distinction being that between animate and inanimate objects. However, it remains unclear whether these categorical distinctions genuinely reflect object category or, alternatively, category-associated visual properties. To address this question, we designed a stimulus set in which animate and inanimate stimuli were carefully matched for shape. Different aspects of visual similarity of the stimuli were measured in three behavioral visual search tasks. We then conducted an fMRI study to test the hypothesis that animate-inanimate organization in VTC response patterns can be explained by visual properties of these categories. We found that it was not the case: although visual dissimilarity predicted neural dissimilarity across the visual cortex, we also found regions in which category information was present even after regressing out visual dissimilarity. We then conducted an MEG study to examine the time course of shape- and category-related information in the brain. Following the analysis approach used in the fMRI study, neural dissimilarity of MEG sensor patterns was modeled using regression analysis, where visual dissimilarity and categorical dissimilarity served as predictors of neural dissimilarity. The results show that visual object properties were strongly contributing to MEG sensor patterns. Surprisingly, when regressing out the contribution of visual properties, no residual category information was present in MEG response patterns. These results suggest that MEG sensor patterns evoked by visually presented objects predominantly reflect visual object properties. Taken together, these findings suggest that MEG is less sensitive to object category information that is independent of shape information
Dynamics of Vortices and their Interactions in Bose-Einstein Condensates
No full textVortex reconnections and interactions play a fundamental role in the dynamics of fluids and turbulent flows, both in the classical and quantum regime. Studying vortices in a clean system like ultracold gases can therefore help, as a bottom-up approach, to understand the physics in a wider context, including superfluid helium, polariton condensates, fluid dynamics and turbulence, neutron stars and cosmological models. So far vortex-vortex interaction was studied in Bose-Einstein condensates either in rotating systems with the observation of regular Abrikosov lattices or in flat condensates across the Berezinskii-Kosterlitz-Thouless transition. In both cases the geometrical constraints allowed to study just a planar interaction among aligned or anti-aligned vortices. The present study instead is carried out in an axisymmetric cigar-shaped Bose-Einstein condensate. Vortices in prolate structures are also known as solitonic vortices. This geometry is especially suitable for investigating vortex interactions. Indeed vortices are oriented perpendicularly to the condensate axis to minimize their length, hence energy, and, because of the cylindrical symmetry, the orientation of a vortex in the radial plane has no constraints. These facts permit interactions to occur with different incoming relative angles between the vortex lines and with different relative velocities. The strong confinement, acting along the radial axis, enhances also interesting effects due to the boundaries
Molecular Mechanisms and Insights into the Nampt Inhibitor (FK866) Resistance in Cancers
Get PDFNicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in NAD+ biosynthesis from nicotinamide, is one of the major factors regulating cell metabolism and NAMPT is considered a promising target for treating cancer. The NAMPT inhibitor (FK866) has exhibited anticancer activity in several preclinical models by depleting NAD+ and ATP levels. Recently, we showed that FK866 induced translation arrest through the activation of 5’AMP-activated protein kinase (AMPK), inhibition of mTOR/4EBP1 signaling, and phosphorylation of EIF2a in leukemia cells. Cancer drug resistance continues to be a major challenge in medical oncology. Deregulated cellular metabolism is linked to such cell resistance. Indeed, both components of the glycolytic and mitochondrial pathways are involved in altered metabolism conferring chemoresistance in several cancers. In this study, we developed FK866-resistant models in T- lymphoblastic leukemia (CCRF-CEM) and breast cancer (MDA-MB231) cell lines to investigate the molecular mechanism of pharmacoresistance to NAMPT inhibitor (FK866). Our resistant cells were not inhibited at the translational level by FK866 and the drug-induced metabolic adaptations of the resistant cells conferred an advantage to counteract FK866 toxicity. We reveal a molecular mechanism by which FK866 resistant CCRF-CEM cells utilize alternative sources for NAD production to fuel cell metabolism, and metabolic reprogramming was associated to the drug resistance. Importantly, the FK866- induced metabolic alteration was overcome by the co-administration of FK866 with compounds targeting metabolism, thereby rendering a synergistic outcome and restoring cell susceptibility towards FK866. We highlighted a molecular target that favors acquiring of resistance in leukemia and breast cancer cells. In conclusion, targeting metabolic alterations associated with drug resistance to FK866 may open up unexplored opportunities for the development of new therapeutic strategies as a combinatorial treatment for cancer
Sul controllo dei medicinali ad uso umano: funzione e scelte amministrative integrate europee.
No full textIl presente lavoro tratta del sistema integrato europeo di governance dei prodotti medicinali ad uso umano. In particolare, è considerata l’amministrazione preposta al controllo all’immissione in commercio dei farmaci ed i relativi procedimenti di prima autorizzazione. Tali argomenti hanno successivamente aperto l’indagine verso una ricostruzione di un parametro di legittimazione e controllo dell’attività di governance anche in sede giurisdizionale. La prospettiva scelta nello svolgimento dello studio è quella europea, poiché da tale dimensione sovranazionale scaturisce la disciplina su cui sono plasmate le legislazioni nazionali. In tal senso, sono state considerate specificamente le normative italiane e britanniche. All’analisi del dato di legge si è affiancato un approfondimento extragiuridico negli ambiti della teoria della scienza e della filosofia che si credono necessari per individuare l’effettiva portata significante del dato normativo. Quest’ultima analisi è svolta nel capitolo quarto, nel quale è considerato anche l’orientamento giurisprudenziale europeo più significativo nell’ottica di armonizzazione del controllo funzionalizzato della governance in esame. Nei capitoli precedenti, dopo l’introduzione storica (capitolo 1), si è sviluppata la descrizione dell’organizzazione del network di governance europeo italiano ed inglese (capitolo 2) e, quindi, dei procedimenti di prima autorizzazione (capitolo 3)