We investigate and compare applications of the Zilber–Pink conjecture and dynamical methods to rigidity problems for arithmetic real and complex hyperbolic lattices. Along the way, we obtain new general results about reconstructing a variation of Hodge structure from its typical Hodge locus that may be of independent interest. Applications to Siu’s immersion problem are also discussed, the most general of which only requires the hypothesis that infinitely many closed geodesics map to proper totally geodesic subvarieties under the immersion.

Bochvar algebras consist of the quasivariety $\mathsf {BCA}$ playing the role of equivalent algebraic semantics for Bochvar (external) logic, a logical formalism introduced by Bochvar [4] in the realm of (weak) Kleene logics. In this paper, we provide an algebraic investigation of the structure of Bochvar algebras. In particular, we prove a representation theorem based on Płonka sums and investigate the lattice of subquasivarieties, showing that Bochvar (external) logic has only one proper extension (apart from classical logic), algebraized by the subquasivariety $\mathsf {NBCA}$ of $\mathsf {BCA}$. Furthermore, we address the problem of (passive) structural completeness ((P)SC) for each of them, showing that $\mathsf {NBCA}$ is SC, while $\mathsf {BCA}$ is not even PSC. Finally, we prove that both $\mathsf {BCA}$ and $\mathsf {NBCA}$ enjoy the amalgamation property (AP).

The impact of urban gardens on food production and nutrient supply is widely recognized in the literature but seldom quantified. In this paper, we present the results of a semi-structured interview conducted in the ‘social gardens’ of Prato (Italy), i.e. areas of land assigned by the Municipality to individual pensioners or unemployed people for the cultivation of vegetables intended for domestic consumption. Some demographic and socio-economic aspects, the cultivated crops and the related areas were investigated. Starting from the areas, the total production of vegetables and their minerals and vitamins contents were estimated. The typical gardener was male, retired, with an average age of 74, and a low level of education. Gardening enabled pensioners to utilize their free time, facilitated physical activity, promoted socialization, and stimulated self-esteem. A 50 m2 plot cultivated on 40% of the area produced an estimated amount of 90 kg of vegetables per year, equivalent to approximately 61.5% of a person's fruit and vegetable needs. Tomato, by far the predominant species, occupied more than 80% of the cultivated area. The highest contributions to nutrients intake concerned Vitamin C and Vitamin A, the lowest Ca and Na. A higher yield and a greater and more balanced nutrient supply could be easily obtained through better use of the land (reduction of uncultivated area and greater assortment of vegetables). In our view, raising gardeners' awareness of this aspect and involving them in training programs on agricultural practices, vegetables composition, and nutrition, could be helpful for increasing the nutrient productivity of the plots and, ultimately, for strengthening the productive function of social gardens.

This paper describes the relationships between large-scale modes of climate variability and its related weather types with the fluctuations in the yield of maize crops in Veneto, Italy. The teleconnections analysed in this work are the winter North Atlantic Oscillation (NAO) and the summer North Atlantic Oscillation (SNAO); the West African monsoon (WAM) and the Intertropical Front (ITF). Despite that these indices are not rigorously linked to one another, they result in being considerably related to atmospheric circulation regimes and associated weather types. They have an impact on temperature and precipitation patterns in Italy and on yields of maize crops in Veneto, a region located in northeast Italy. Yields are strongly affected by large-scale temperate and tropical variability directly through three main circulation regimes. Troughing weather regimes that produced below average temperatures depress yields over the entire Veneto region, as does the zonal regime that affects rainfall. Results confirm the relevance of large-scale modes and associated weather regimes and types on maize crop yields fluctuations in Veneto.