On the asymptotic behaviour of solutions to the fractional porous medium equation with variable density

We are concerned with the long time behaviour of solutions to the fractional porous medium equation with a variable spatial density. We prove that if the density decays slowly at infinity, then the solution approaches the Barenblatt-type solution of a proper singular fractional problem. If, on the contrary, the density decays rapidly at infinity, we show that the minimal solution multiplied by a suitable power of the time variable converges to the minimal solution of a certain fractional sublinear elliptic equation.Comment: To appear in DCDS-

Global existence for reaction-diffusion evolution equations driven by the p-Laplacian on manifolds

We consider reaction-diffusion equations driven by the p-Laplacian on noncompact, infinite volume manifolds assumed to support the Sobolev inequality and, in some cases, to have L2 spectrum bounded away from zero, the main example we have in mind being the hyperbolic space of any dimension. It is shown that, under appropriate conditions on the parameters involved and smallness conditions on the initial data, global in time solutions exist and suitable smoothing effects, namely explicit bounds on the L∞ norm of solutions at all positive times, in terms of Lq norms of the data. The geometric setting discussed here requires significant modifications w.r.t. the Euclidean strategies

Measuring the effect of formal education on income inequality: A longitudinal analysis across Mediterranean countries

The paper aims at investigating the role of gender and personal education in explaining differences in generating individual earnings and their effects on income inequality. The analysis involves four countries of Southern Europe (Greece, Italy, Portugal, and Spain) in light of the macroeconomic and institutional settings and policy frameworks. Once that the main determinants of income have been sketched through random effects models, the ANOGI (Analysis of Gini) decomposition is performed in order to evaluate the contribution of each subgroup of population with different formal education to the overall income inequality and to assess the degree to which each subpopulation is stratified. In short, Greece and Portugal show the largest gender earnings gaps and the largest differences in returns on education, while earnings inequality is more severe for Italian and Portuguese women. In each country, except for Italy, lower educated workers show the lowest amount of overlapping and, therefore, high levels of income stratification, while higher educated individuals are usually less stratified. Italy instead shows similar degrees of overlapping for both the lowest and the highest education levels

Understanding pro-environmental travel behaviours in Western Europe

This study aims at understanding, from a gender perspective, the reasons behind citizens’ choice of using public transport, and whether this choice is driven by pro-environmental behaviour. Using Eurobarometer data (2013), we perform ordered logistic regressions comparatively for Germany, Italy and the Netherlands. Financial, political and environmental factors are shown to have significant roles in shaping travel behaviours, with interesting gender and cross-country differences

Network communities of dynamical influence

Fuelled by a desire for greater connectivity, networked systems now pervade our society at an unprecedented level that will affect it in ways we do not yet understand. In contrast, nature has already developed efficient networks that can instigate rapid response and consensus when key elements are stimulated. We present a technique for identifying these key elements by investigating the relationships between a system’s most dominant eigenvectors. This approach reveals the most effective vertices for leading a network to rapid consensus when stimulated, as well as the communities that form under their dynamical influence. In applying this technique, the effectiveness of starling flocks was found to be due, in part, to the low outdegree of every bird, where increasing the number of outgoing connections can produce a less responsive flock. A larger outdegree also affects the location of the birds with the most influence, where these influentially connected birds become more centrally located and in a poorer position to observe a predator and, hence, instigate an evasion manoeuvre. Finally, the technique was found to be effective in large voxel-wise brain connectomes where subjects can be identified from their influential communities

Exploring antecedents of innovations for small- and medium-sized enterprises' environmental sustainability: An interpretative framework

The need to pursue sustainable development has become a central topic in Western countries due to citizens' greater sensitivity to improving environmental and social conditions. Companies can reach this objective more easily through green innovations, which are now considered a strategic opportunity that simultaneously allows for adherence to sustainable development criteria and the pursuit of competitive advantages. Scholars have identified the determinants that encourage companies to adopt green innovations, but the outcomes of their investigations thus far have often been ambiguous and contradictory. Our paper proposes an interpretative framework for addressing such inconsistencies. Using the partial least squares structural equation modelling (PLS-SEM) methodology, we validate this framework on a sample of small- and medium-sized enterprises (SMEs) and show that SMEs' choices are influenced by cultural elements and stimulated by the prospect of obtaining economic advantages over competitors. SMEs also pay close attention to stakeholder solicitations, while public administration does not affect their eco-innovating choices. The results have policy implications for executives and insiders

Sustainable urban mobility: evidence from three developed European countries

The importance acquired by private cars as the leading travel mode in most advanced countries has drawn attention to concerns related to pro-environmental travel behaviour. Indeed, the car has brought great benefits to society, albeit causing a whole lot of environmental and socio-economic consequences. In this perspective, we exploit Eurobarometer data on the attitudes of Europeans towards urban mobility to investigate the main motivations of citizens’ public transport use frequency. Ordered logistic regressions are estimated by country (Germany, Italy, and the Netherlands) and by gender. Our results suggest the key role played by a comprehensive set of socio-demographic, economic, and environmental aspects in determining urban travel behaviour. Moreover, our investigation brings to light some relevant cross-country and cross-gender commonalities and differences. The provided evidence may give policymakers a better knowledge of travel behaviour, useful for designing new interventions for environmentally-sustainable travelling

Non \ue8 pi\uf9 quella di una volta. La mafia e le attivit\ue0 estorsive in Sicilia

Il volume presenta i risultati di una ricerca volta alla descrizione dei fenomeni estorsivi e della loro intensit\ue0 in Sicilia, raccontando, sulla base di appositi parametri oggettivi e di valutazioni soggettive degli esponenti del mondo delle associazioni e delle forze dell\u2019ordine, le aree pi\uf9 esposte, quelle meno esposte, quelle dove i fenomeni hanno una rilevanza residuale, in una fase in cui i sodalizi mafiosi sono sempre pi\uf9 pressati dall\u2019azione di contrasto. Per raggiungere questo obiettivo ci si \ue8 avvalsi di strumenti qualitativi e dati quantitativi, approfondendo l\u2019analisi delle trasformazioni delle condotte estorsive durante la crisi, concentrandosi in modo specifico su casi emersi nell\u2019ambito di recenti inchieste giudiziarie. Il libro ricostruisce anche la prospettiva e le difficolt\ue0 di alcuni imprenditori siciliani che, dopo aver pagato il pizzo, hanno scelto di denunciare i propri estorsori e di collaborare con le istituzioni

Decapod crustaceans associated with an artificial reef (Adriatic Sea)

The aim of this study is to increase the knowledge on the distribution of decapod crustaceans associated with an artificial reef positioned on sandy-mud bottoms in the central Adriatic Sea. The reef is constituted of concrete modules assembled in pyramids and concrete poles. Hard and soft bottom samples were collected from 2001, just after reef construction, to 2005 (4 surveys per year). Regarding the soft seabed, three sites close to a pyramid, three inside the reef area at a distance of 10-15 m from the structures, and three 200 m outside the reef (control sites) were randomly sampled during each survey. At the same time, three pyramids (vertical and horizontal walls) and three poles were also investigated. After taxonomical analysis, decapod crustaceans were analysed using abundance and species richness. Sites and years were compared using a balanced, fixed effect, 2-way ANOVA and PERMANOVA. In addition, SIMPER analysis was performed to identify those species typifying each community inhabiting both the soft bottom and the artificial substrates. The results showed that the artificial reef induced an increase in both abundance and diversity of the decapods of the natural habitat. In fact, man-made substrates may offer new available space for biological colonization and allow the settlement of new species usually living on hard bottoms, thus increasing the complexity of the original benthic communities

The role of family background in the heterogeneity of self-employment in some transition countries

The aim of this paper is to shed light on how some determinants, especially in the spheres of family background, differently affect the heterogeneous category of self-employment across a set of transition economies of Eastern Europe, where more or less restrictive policies and different liberalization processes have been adopted over time. At this end, three-stage multinomial logit models as discrete choice models are estimated on 2005 EU-SILC data. Country-specific peculiarities of self-employment profiles are drawn and, although the occupational status is often devised in a dualist perspective, significant differentiations within the ranks of self-employed also exist