Changes in root topology of the tussock perennial grass Molinia caerulea were studied in a pot experiment. The target species M. caerulea was grown alone and with Holcus lanatus or Carex hartmanii as a competitor. The root topology in three different soils (sand, humus rich soil and a mixture of both) was measured. Influence of competitive pressure on root topology was determined in terms of root biomass surrounding the target root. Whereas no simple significant changes in root topology due to soil quality were observed, an increase in competition pressure caused a shift of root topology towards a more herringbone structure. This shift was greatest in nutrient poor sand and least in humus-rich soil. In addition, an influence of individual competitors on topological changes in humus-rich soil was observed after excluding the effect of total root biomass.
This review study analyses Martin Nitsche’s monograph devoted to Heidegger’s Contributions to philosophy (Beiträge zur Philosophie), primarily addressing the question of whether Nitsche succeeds in displaying the phenomenological character of the Contributions. It identifies a key step in Nitsche’s interpretation; that is, Heidegger’s shift from emphasising the specific entity of Dasein to emphasising the distinctive “phenomenological” or “relational field”, which is understood as an “ontological locality”. The study focuses on the question of whether it is possible, subsequent to this shift, to preserve the phenomenological character of (Heidegger’s) thought, and it arrives at a negative conclusion in this regard: Heidegger does not offer a phenomenological description - nay, he presents a conceptual, or perhaps even narrative, structure, in which he lays claim to the possibility of speaking from a principled position of (the experienced) “enowning”., Martin Ritter., and Obsahuje poznámky a bibliografii
The border effect is one of the problems, which can appear in the application of self-organizing maps (SOM). Different solutions were presented in the literature, but each of them has its drawbacks. In this paper we present a new method for overcoming the border effect - optimized spiral spherical SOM. We also show that standard measure of irregularity is not appropriate and present a modified version - Gaussian measure of irregularity. Our simulations suggest that the new variant of SOM achieves extremely low values of irregularity in comparison to other methods. At the end of the paper we present a software solution for the proposed method.
In this paper we introduce the notation of t-best approximatively compact sets, t-best approximation points, t-proximinal sets, t-boundedly compact sets and t-best proximity pair in fuzzy metric spaces. The results derived in this paper are more general than the corresponding results of metric spaces, fuzzy metric spaces, fuzzy normed spaces and probabilistic metric spaces.
In this paper we study the topological and metric rigidity of hypersurfaces in ${\mathbb H}^{n+1}$, the $(n+1)$-dimensional hyperbolic space of sectional curvature $-1$. We find conditions to ensure a complete connected oriented hypersurface in ${\mathbb H}^{n+1}$ to be diffeomorphic to a Euclidean sphere. We also give sufficient conditions for a complete connected oriented closed hypersurface with constant norm of the second fundamental form to be totally umbilic.