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With or without you. Intentions, Constraints and Consequences of Childlessness in European Countries.
Full text linkThis dissertation focuses on the experience of childlessness, which is an increasing one across European Countries. Namely, it deals with the socio-economic drivers and consequences that distinguish the life of childless individuals from that of parents. Mirroring each phase of a hypothetical individual lifecycle, it starts by analysing how intentions to be childless are later realised their realizations (Chapter 2). It then goes on to investigate the individual and contextual determinants of childlessness and how they have changed over time (Chapter 3 and Chapter 4). Last it considers the consequences that childlessness might induce in adulthood and later life (Chapter 5). This is done by combining demographic and sociological perspectives in a joint interpretative framework. Overall the thesis shows that both economic contraints and individual values has a role in determining the choice of a childless life, and highlights how these decisions are taken in contexts where a purality of macro factors interacts in moderating the indivdidual risk of being childless. Understanding the drives to childlessness is relevant also when interpreting the potential effects that being childless has on the life of individuals. All in all, the study shows that the consequences of being childless also depend on how people came to be without children
Reading Between the Lines: Conversational Implicature Processing in Typical and Atypical Populations
Full text linkThis thesis' aim is to add some pieces to the complex puzzle on the mechanism behind the comprehension of conversational implicatures. To do so, in a series of experiment we manipulated both the type of implicatures (scalar vs. ad-hoc) and the population under investigation (typical vs. atypical; children vs. adults)
The two core systems of numerical cognition in infants and developmental dyscalculia
Full text linkThe present dissertation collects several works that aim to examine multiple aspects of ANS and OTS during infancy. In particular, the predictive role of ANS on mathematical abilities, the importance of dynamic information in OTS and the role of OTS and ANS in developmental dyscalculia
Social dynamics and behavioral response during health threats
Full text linkThe interplay between human behavior and the spreading of an epidemics represents a challenge in modeling the dynamics of infectious diseases. The technological revolution that we are experiencing nowadays gives access to new sources of digital data, capable of capturing behavioral patterns and social dynamics of our society and opening, in fact, the path to new opportunities for mathematical modelers. Provided by such tools, we discuss two different aspects of the dynamics of infectious diseases associated with human behavior. In the first part of the thesis, we focus on the mechanism driving the awareness of individuals during public health emergencies and describe epidemiological models especially tailored to better understand the underline features of the risk perception. The proposed framework is able to disentangle and characterize the contribution of media drivers and social contagion mechanisms in the building of awareness of individuals about infectious diseases. In the second part of the thesis, we present a data driven computational model aiming to assess the potential risk of experiencing measles re-emergence in Turkey. This study takes into consideration the recent massive migration of Syrian refugees in Turkey, which changed the social structure and focuses on the possible outbreak of an infectious disease, such as measles, as a consequence of the great concentration of Syrian refugees not adequately immunized against it. The model proposed is informed with mobility patterns inferred from mobile phone data and accounts for the different hypothetical policies adopted to integrate the refugees with the Turkish population
Sustainable landfilling of municipal solid waste
Full text linkThe deposition of waste in a landfill can be a threat to the environment and human health; in spite of their potential pollution, landfill are still of grate use for the residual municipal solid waste, thus efficient and cost effective technologies need to be studied in order to minimize aqueous and gaseous emissions. The present work focuses on the evaluation of the remediation of old landfill sites that pollutes groundwater and on the determination of a new pre-treatment of fresh waste upstream of landfilling. First the biosparging technology has been applied to remediate an aquifer polluted by leachate. The biosparging stimulates the growth of indigenous bacteria able to convert pollutants, such as ammonium nitrogen, in harmless compounds. The technology shows high efficiency in ammonium nitrogen removal via nitrification processes. The biosparging remediation technology prevents the mobilization of metals and removes the nitrates produced in the nitrification process when the organic carbon source is conveniently dosed. The application of the biosparging on site has proven to be feasible. The Solidification/Stabilization (S/S) technology is a pre-landfill waste treatment process, which has been used for different types of hazardous wastes since it has a proved efficiency on heavy metal immobilization. The S/S process uses chemically reactive formulations that, together with the water, form stable solids; it also insolubilizes, immobilizes, encapsulates, destroys, sorbs, or otherwise interacts with selected waste components. The S/S process improves the physical characteristics of the waste and reduces the mobility of the hazardous compounds, thus the waste leaches less contaminants into the environment. The result of this process is a less hazardous solid. The experimental evidences proved that this technology reduces volumes used for landfilling and inhibits the methanogenesis blocking greenhouse gases emissions. The reduced permeability and the leaching test results show that the leachate produced is of a smaller amount and less polluted. The enhanced mechanical properties and the reduced emissions both in bodies of water and atmosphere have proven the worth of this technology. Therefore an alternative waste treatment plant involving S/S pre-treatment is proposed
On the mechanical behavior of single-cell: from microstructural remodelling to macroscopic elasticity
Full text linkCells physical properties and functions like adhesion, migration and division are all regulated by an interplay between mechanical and biochemical processes occurring within and across the cell membrane. It is however known that mechanical forces spread through the cytoskeletal elements and reach equilibrium with characteristic times at least one order of magnitude smaller than the ones typically governing propagation of biochemical signals and biological phenomena like polymerization/depolymerization of protein microfilaments or even cell duplication and differentiation. This somehow allows to study as uncoupled many biochemo-
mechanical events although they appear simultaneously and as concatenated. In this work, the complex machinery of the cell is hence deprived of its biochemical processes with the aim to bring out the crucial role that mechanics plays in regulating the cell as a whole as well as in terms of some interactions occurring at the interface with the extra-cellular matrix. In this sense, the single-cell is here described as a mechanical unit, endowed with an internal micro-architecture –the cytoskeleton– able to sense extra-cellular physical stimuli and to react to them through coordinated structural remodelling and stress redistribution
that obey specific equilibrium principles. By coupling discrete and continuum theoretical models, cell mechanics is investigated from different perspectives, thus deriving the cell overall elastic response as the macroscopic projection of micro-structural kinematics involving subcellular constituents. Finally, some optimal arrangements of adherent cells in response to substrate-mediated elastic interactions with external loads are explored and compared with experimental evidences from the literature
Experimental and Novel Analytic Results for Couplings in Ordered Submicroscopic Systems: from Optomechanics to Thermomechanics
Full text linkTheoretical modelling of challenging multiscale problems arising in complex (and sometimes bioinspired) solids are presented. Such activities are supported by analytical, numerical and experimental studies. For instance, this is the case for studying the response of hierarchical and nano-composites, nanostructured solid/semi-fluid membranes, polymeric nanocomposites, to electromagnetic, mechanical, thermal, and sometimes biological, electrical, and chemical agents. Such actions are notoriously important for sensors, polymeric films, artificial muscles, cell membranes, metamaterials, hierarchical composite interfaces and other novel class of materials.
The main purpose of this project is to make significant advancements in the study of such composites, with a focus on the electromagnetic and mechanical performances of the mentioned structures, with particular regards to novel concept devices for sensing. These latter ones have been studied with different configuration, from 3D colloidal to 2D quasi-hemispherical micro voids elastomeric grating as strain sensors.
Exhibited time-rate dependent behavior and structural phenomena induced by the nano/micro-structure and their adaptation to the applied actions, have been explored.
Such, and similar, ordered submicroscopic systems undergoing thermal and mechanical stimuli often exhibit an anomalous response. Indeed, they neither follow Fourier’s law for heat transport nor their mechanical time-dependent behavior exhibiting classical hereditariness. Such features are known both for natural and artificial materials, such as bone, lipid membranes, metallic and polymeric “spongy” composites (like foams) and many others. Strong efforts have been made in the last years to scale-up the thermal, mechanical and micro-fluidic properties of such solids, to the extent of understanding their effective bulk and interface features. The analysis of the physical grounds highlighted above has led to findings that allow the describing of those materials’ effective characteristics through their fractional-order response. Fractional-order frameworks have also been employed in analyzing heat transfer to the extent of generalizing the classical Fourier and Cattaneo transport equations and also for studying consolidation phenomenon.
Overall, the research outcomes have fulfilled all the research objectives of this thesis thanks to the strong interconnection between several disciplines, ranging from mechanics to physics, from structural health monitoring to chemistry, both from an analytical and numerical point of view to the experimental one
Investigating individual traits, network dynamics and economic behavior using mobile phone data
No full textRecent years have witnessed a growing interest in analyzing the huge amount of human behavioral data generated by new technologies such as mobile phones, social media and credit cards. These technologies leave a trail of "digital breadcrumbs" that allow us to have new quantitative insights that may reveal patterns of individual and group behaviors. Moreover, it allows us to better understand human behavior at a fine-grained resolution and for periods of time that were previously inconceivable. Researchers can now observe human behavior, ask research questions and run experiments in ways that were simply impossible in the recent past due to qualitative methods that, despite their undeniable benefits, proved to be time and resource consuming and therefore difficult to apply to large scale studies.
Studying social interaction and social networks extracted from these data sources, allow us to understand not only individual behaviors and their characteristics, but also to observe the relationships between individuals, the structure, the content and their dynamics over long periods of time. Given the capacity of mobile phones to capture real observations of communications between people, we took advantage of the data collected from these devices to further explore and investigate human behavior.
Specifically, in this dissertation, we (i) present the Mobile Territorial Lab (MTL) project and illustrate the advantages of using a living lab approach to collect a longitudinal set of data from a target group of parents; (ii) investigate how the personality dispositions of an individual influence how (s)he manages her/his social network; (iii) investigate whether and how the behavior of an individual as sensed through her/his mobile phone behavior is related to the future adoption and use of the leading mobile money service M-Pesa
Gli elementi soggettivi delle cause di giustificazione
Full text linkLa tesi si propone di risolvere il quesito relativo all'imputazione soggettiva delle cause di giustificazione. Il tema è affrontato sul piano dell'esegesi delle cause previste nella parte generale del codice penale; sul piano della costruzione sistematica dell'illecito; infine su quello valoriale
Nonlinear and Hybrid Feedbacks with Continuous-Time Linear Systems
Full text linkIn this thesis we study linear time-invariant systems feedback interconnected with three specific nonlinear blocks; a play/stop operator, a switching-reset mechanism, and an adaptive dead-zone. This setup resembles the Lure problem studied in the absolute stability framework, but the types of nonlinearities considered here do not satisfy
(in general) a sector condition. These nonlinear blocks give rise to a whole range of interesting phenomena, such as compact sets of equilibria, hybrid omega-limit sets, and state constraints. Throughout the thesis, we use the hybrid systems formalism to describe these
phenomena and to analyze these loops. We obtain sharp stability conditions that can be formulated as linear matrix inequalities, thus verifiable with numerically efficient solvers.
Finally, we apply the theoretical findings to two automotive applications