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Abstract The mass transport of contaminants in porous media is of great importance both in the field of research and in the applied field. Today's respect for the environment and the safeguarding of resources has greatly increased the need to monitor and prevent environmental pollution. Of great importance are the mathematical models that allow us to describe the concentration distribution in space and time of a pollutant in groundwater. This research is focused on the study and modeling of pollutants in groundwater. Bibliographic research and a subsequent in-depth study of 1D, 2D and 3D ADE models and their applications were conducted to examine the state of the art and possible areas for model development. Emphasis was placed on the development of a new one-dimensional solution. A variety of conditions were examined including the release of the source with step function, the decay of contaminants with consecutive reactions and the production and decay of the source concentration From the one-dimensional model, it was possible to extend the model to three-dimensions with the exact integral solution and approximate solution in closed form. A solution in approximate form was also obtained for a known solution in the Literature characterized by exponential decay at the source. A comparative simulation analysis was performed on the models based on Literature data.

Defence date: 28 May 2015 Examining Board: Professor Andrea Mattozzi, Supervisor, EUI; Professor Andrea Ichino, EUI; Professor Peter Fredriksson, Stockholm University; Professor Tarjei Havnes, University of Oslo. Abstract The first chapter analyzes the effects of commercial television in Norway. Matching data on cable television networks with individual-level administrative register data, we find that the expansion of commercial television reduced ability test scores as well as high school graduation rates. We find stronger effects on sons of low-income parents and particularly large effect for children in elementary school. Aggregate data show a substantial drop in time spent reading by young people in the same period, suggesting that television watching may have crowded out more cognitively stimulating activities such as reading. This chapter is joint work with Simen Markussen and Knut Røed. The second chapter investigates how sickness absence behaviour in Norwegian municipalities was affected by the terrorist attack in Norway on July 22, 2011. Using register data covering the complete Norwegian population, I find that sickness absence rates declined substantially in municipalities affected more intensely by the attack. In municipalities from which a resident was killed in the attack, sickness absence rates declined by 4% compared to municipalities without victims. The effect is precisely estimated, stable across several challenging specifications, and persists for as long as there is available data. The effect for people in their 20's is more than twice that for the population at large – for this group, local exposure to the attack decreased absence rates by around 10%. The third chapter exploits a natural experiment in the Norwegian political system. I find that obtaining the right to vote at a lower age is associated with substantially higher turnout among first-time voters, and that this is driven by parental influence. Counter to conventional wisdom about the habitual nature of voting, this difference in political participation does not persist for subsequent elections.

This thesis is devoted to the study of psychological factors associated with HIV infection. It consists in three theoretical chapters and eight empirical studies. The first chapter illustrates the basis of psychoimmunology and the evidence about the connection between psychosocial factors and the immune system functioning. The second is a general introduction to HIV/AIDS illness and its physiopsychological consequences. The third is devoted to the discussion of psychosocial factors associated HIV progression; the physiological and behavioral pathways that may mediate the associations between psychological factors and HIV progression have been illustrated. The fourth chapter consists in eight studies that we have conducted. The first one consists in a comparison between HIV-positive and HIV-negative individuals with respect to depression rates and symptomatology, together with the effect of romantic relationship on depression. The second study explores HIV-positive patients’ illness perceptions and the strategies of coping. The third study is devoted to the investigation of emotions (implicit and explicit) and alexithymia. Such constructs have been then tested in relation with HIV-progression biomarkers. The fourth study investigates the personality types and their psychological correlates (e.g., emotions and coping strategies). In the fifth study, the concept of minority stress has been investigated in a sample of gay and bisexual men. In the sixth study, we tested the relationship of minority stress concept to HIV progression biomarkers, in two samples of HIV positive gay and bisexual men. The seventh study is dedicated to the study of HIV adherence self-efficacy and its relationship with compliance and HIV progression. The eighth study is devoted to the investigation of psychological and physiological correlates of perceived stress in HIV-positive individuals. In this study, we investigated the connection between the activation of immune system and depression, and how perceived stress might influence physical health of patients. Furthermore, patients’ psychological characteristics that might exert a protective effect against perceived stress and depression have been also evaluated.

This research aims to discuss some problems and to suggest some reflections about the earliest Phoenician settlement on Sardinia, especially focusing on the 8th and 7th century BC. Through a methodological reflection on colonialism and a re-examination of the archaeological evidence of the Phoenician presence on the island, taking into account funerary, ritual (tofet) and settlement contexts, the present study proposes an alternative interpretation to the traditional and conventional view that sees the Phoenician presence from the mid-8th century BC in ‘colonial’ terms. Analysis of the archaeological evidence from sites conventionally assumed as Phoenician colonial establishments calls into question both the chronology and the relationships between the different ethnic groups involved in the presumed colonial process. It is suggested that the island of Sardinia cannot be regarded as a monolithic and uniform background to the arrival of eastern sailors, and that specific regions such as the coastal area around Sulky must be examined on a strong contextual basis.

Memory mapping has traditionally been an important optimization problem for high-performance parallel systems. Today, these issues are increasingly affecting a much wider range of platforms. Several techniques have been presented to solve bank conflicts and reduce memory access latency but none of them turns out to be generally applicable to different application contexts. One of the ambitious goals of this Thesis is to contribute to modelling the problem of the memory mapping in order to find an approach that generalizes on existing conflict-avoiding techniques, supporting a systematic exploration of feasible mapping schemes.

Defence date: 03 October 2018 Examining Board: Prof. David K. Levine, EUI (Supervisor); Prof. Giacomo Calzolari, EUI; Prof. Juan-José Ganuza, UPF and Barcelona GSE; Prof. Gerard Llobet, CEMFI The aim of this thesis is to investigate cartels and the impact of competition policy from various angles. Chapter 1, joint with Joan-Ramon Borrell, José Manuel Ordóñez-de-Haro and Juan Luis Jiménez, analyzes the relationship between cartel life cycles and business cycles. We analyze the relationship between cartel startups/breakups and economic cycles using a dataset of cartels sanctioned by the European Commission. Results show that cartels are more likely to be formed when the business has evolved positively in the previous months and managers expect prices to decline, but that cartels also tend to breakup when the business has evolved positively. Upturns in firm-specific business cycles appear to cause cartel turnovers: existing cartels die while new ones are set up. Chapter 2 aims at obtaining a precise measure of how much firms benefit from collusion. I evaluate the causal effect of being a cartel member on the revenues and profits of cartelized firms, using comparable non-collusive firms as control group. A dataset of discovered cartel cases in Spain from 1990 to 2014 and an alternative dataset of firms’ balance sheets are used. Results show that firms increase their revenues, on average, between 19% and 26% due to the collusive agreement, while no significant effect is found on profits. Estimations by cartel duration demonstrate that the members of long-lasting cartels not only increase their revenues (29%−50%), but also their profits more than two times. Further analysis shows that cartels that are profitable from the beginning tend to last longer and do not apply for Leniency Programs. Chapter 3, joint with Joan-Ramon Borrell, Juan Luis Jiménez and José Manuel Ordóñezde-Haro, investigates how Leniency Programs destabilize cartels. We study the effect of the Leniency Program on cartel duration, cartel fines and on the years of investigation using a difference-in-differences program evaluation approach. Cartel cases discovered by the European Commission and the Spanish Competition Authority are analyzed. Results show a short-run effect of the Leniency Program: the detected cartels have longer duration than the ones in the control group. In the long-run, the program decreases cartel duration. On the other hand, no significant effect is found on fines, while the duration of the investigation decreases significantly around 0.8-1.3 years.

Award date: 17 June 2022. Supervisor: Professor, Claudius Wagemann, European University Institute In November 2021 the Polish authorities had registered over 30 000 illegal border-crossing attempts at the Belarussian border since the beginning of the year. Although this number also takes into account people making multiple attempts to cross, still this number is unprecedent and unexpected as the Lithuania, Latvia, and Poland border with Belarus, is not usually used as a migration door toward the European Union (EU). This new migration flow has been engineered by Belarus’ President Alexander Lukashenko in reaction to the EU’ sanctions against his authoritarian regime. The use of hybrid threats like the instrumentalisation of populations for blackmail purpose is increasing, and EU’s vulnerability toward this new coercive trend with it. This study analyses what makes EU vulnerable to ‘coercive engineered migration’, and what are the solutions to face and overcome this phenomenon.