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In this paper, we want to study the link between the presence of compact objects with some analytic structure and the global geometry of a weakly complete surface. We begin with a brief survey of some now classic results on the local geometry around a (complex) curve, which depends on the sign of its self-intersection and, in the flat case, on some more refined invariants (see the works of Grauert, Suzuki, Ueda). Then, we recall some results about the propagation of compact curves and the existence of holomorphic functions (from the works of Nishino and Ohsawa). With such considerations in mind, we give an overview of the classification results for weakly complete surfaces that we obtained in two joint papers with Slodkowski (see Mongodi et al. (Indiana Univ. Math. J., 67(2), 899-935 (2018); Int. J. Math., 28(8), 1750063, 16 (2017))) and we present some new results which stem from this somehow more local (or less global) viewpoint (see Sections 4.2, 4.3, and 5).

This paper concludes a book on ‘cultural traits’ which features 20 contributions from the most diverse disciplines, from cultural anthropology to archaeology, from psychology to history, from economics to musicology. The paper dodges the attempt to make a conceptual synthesis, arguing positively for such avoidance. Borrowing a term from the U.S. National Evolutionary Synthesis Center, the paper likens the book, Understanding Cultural Traits, to a catalysis meeting, i.e., a lowering of disciplinary barriers that influences the disciplines’ culture of data, broadens the scientific vision, and generates scientific collaborations. Catalysis is not alternative to synthesis. It is a different phase of scientific progress, one that can be hindered by an obsession for concepts and by an urge to close the discourse.

In this paper we identify and discuss key topics characterizing recent information quality research and their impact on future research perspectives in a context where information is increasingly diverse. The investigation considers basic issues related to information quality definitions, dimensions, and factors referring to information systems, information representation, influence of the observer and of the task. We conclude the paper by discussing how philosophical studies can contribute to a better understanding of some key foundational problems that emerged in our analysis.

This paper examines patterns of Foreign Direct Investment (FDI) inflows to Southern European (SE) regions, which seem to be at the margin of the FDI attraction game accounting for a very small share of total inward FDI in the EU. In order to understand why these regions have attracted such a low number of foreign investors, this contribution provides the following analysis: (i) an overall picture of the main characteristics of patterns of inward FDI in SE regions at geographical and sectoral levels; (ii) the factors that drive FDI flows into EU regions; (iii) an assessment of the potential attractiveness of SE regions, both in absolute terms and with respect to other EU regions. The main results indicate that SE regions are definitively less attractive than other EU regions, though a lot of variation does exist at both geographical and sectoral levels. In order to improve their capacity to attract FDI, SE regions should improve their factors of attractiveness by implementing several structural reforms.

Pedestrian flows are characterised by the preponderant presence of groups, with particular reference to dyads. The paper presents a research focused on group and age-driven pedestrian behaviour in an urban crowded scenario. Data analysis was performed by using an open source tracker tool. Results showed that in situation of irregular flows (LOS B) dyads walked 30% slower than singles, and that elderly walked 40%slower than adults. The achieved results have been used towards the validation of the simulation platform ELIAS 38, with reference to the representation of the granulometric distribution of groups and heterogeneous speed profiles

The chapter explains why evolutionary genetics - a mathematical body of theory developed since the 1910s - eventually got to deal with culture: the frequency dynamics of genes like “the lactase gene” in populations cannot be modeled correctly without including social transmission. The body of theory requires specific justifications, for example meticulous legitimations of describing culture in terms of traits. It is an immensely valuable scientific instrument, not only for its modeling power but also for the amount of work that has been necessary to build, maintain, and expand it. To demonstrate such patrimony, and to emphasize the importance and accumulation of statistical knowledge therein, this paper tells a brief history of evolutionary genetics, explaining also the probabilistic nature of genotypes, phenogenotypes and population phenomena. Although evolutionary genetics is actually composed by distinct and partially independent traditions, the most important mathematical object of evolutionary genetics is the Mendelian space, and evolutionary genetics is mostly the daring study of trajectories of alleles in a population that explores that space. The ‘body’ is scientific wealth that can be invested in studying every situation that happens to turn out suitable to be modeled as a Mendelian population, or as a modified Mendelian population, or as a population of continuously varying individuals with an underlying Mendelian basis. Mathematical tinkering and justification are two halves of the mutual adjustment between the body of theory and the domain of culture. Some works in the current scientific literature overstate justification, misrepresenting the relationship between body of theory and domain, and hindering interdisciplinary dialogue.

The attention placed on healthcare systems has been constantly increasing in recent years. This is especially true for geriatric services: older people often have complex medical and social needs and the proportion of elderly in the population is currently rising. In this paper we apply the Coxian phase-type distribution to model the length of stay of geriatric patients admitted to 19 geriatric wards at hospitals in the Emilia-Romagna region in Italy for the years 2008–2011. The results confirm previous research carried out on patients in the UK and extends the research by allowing the influence of patient characteristics, available on admission, to be taken into account as covariates.

Rockfalls pose a significant threat to life and property, thus rockfall protection is a major issue in areas exposed to severe rockfall hazard. Rockfall protection approaches include quantitative rockfall hazard and risk assessment, as well as the design of structural countermeasures. These require a sound and robust quantification of 3D rockfall trajectories, distribution and intensity of impacts, and magnitude and variability of involved dynamic quantities. Providing highly reliable modeling inputs to rockfall protection remains a difficult task, because of the complexity and intrinsic stochastic nature of rockfall physics and the uncertainty of all the relevant parameters. However, significant advances in rockfall analysis have been made in the last decade, and modern 3D rockfall modeling techniques now provide effective tools to support rockfall protection activities, even in difficult design conditions. Nevertheless, their use can still be complex and raises a series of difficult steps both in the modeling and the analysis of the results. In this paper, we provide an overview of rockfall analysis aspects relevant to rockfall protection, as well as examples of applications of modern 3D rockfall runout modeling techniques in rockfall hazard and risk assessment, and countermeasure selection, design and optimization. .

The Minimum Path Cover problem on directed acyclic graphs (DAGs) is a classical problem that provides a clear and simple mathematical formulation for several applications in different areas and that has an efficient algorithmic solution. In this paper, we study the computational complexity of two constrained variants of Minimum Path Cover motivated by the recent introduction of next-generation sequencing technologies in bioinformatics. The first problem (MinPCRP), given a DAG and a set of pairs of vertices, asks for a minimum cardinality set of paths “covering” all the vertices such that both vertices of each pair belong to the same path. For this problem, we show that, while it is NP-hard to compute if there exists a solution consisting of at most three paths, it is possible to decide in polynomial time whether a solution consisting of at most two paths exists. The second problem (MaxRPSP), given a DAG and a set of pairs of vertices, asks for a single path containing the maximum number of the given pairs of vertices. We show its NP-hardness and also its W[1]-hardness when parametrized by the number of covered pairs. On the positive side, we give a fixed-parameter algorithm when the parameter is the maximum overlapping degree, a natural parameter in the bioinformatics applications of the problem.