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Kenny Štorgel  completed his studies at UP FAMNIT with the doctoral thesis »Certain Graph-Theoretic Invariants and Decompositions: From Structure to Bounds and Algorithms« under the mentorship of Assoc. Prof.  Borut Lužar and co-mentorship of Prof. Martin Milanič.

Doctoral dissertation summary: »Certain Graph-Theoretic Invariants and Decompositions: From Structure to Bounds and Algorithms«

The first part of the dissertation focuses on various graph invariants related with colorings of planar graphs. Among the results of this part are certain generalizations of known results on proper colorings, a new affirmative result in the direction of proving an open conjecture on cyclic colorings and improved bounds for parity colorings of planar graphs. The second part of the dissertation then focuses on special not yet fully understood graph classes where absence of large cliques is necessary and sufficient condition for the existence of tree decompositions of small width and the study of closely related and fairly new invariant called the tree-independence number. Algorithmic consequences for the aforementioned graph classes are also examined and it shows that certain problems are solvable in polynomial time in such graph classes.

Sara Zupan, employee at UP FAMNIT, completed her studies at UP FHŠ with the doctoral thesis »The influence of geographic and ecological isolation of populations of the False ringlet butterfly Coenonympha oedippus (Lepidoptera: Nymphalidae) on genetic structure and phenotype expression« under the mentorship of Assoc. Prof. Jure Jugovic and co-mentorship of Prof. Elena Bužan and Assoc. Prof. Valentina Brečko Grubar.

Doctoral dissertation summary: »The influence of geographic and ecological isolation of populations of the False ringlet butterfly Coenonympha oedippus (Lepidoptera: Nymphalidae) on genetic structure and phenotype expression«

False Ringlet is an endangered species of butterfly that inhabits phytocenologically and geographically contrasting habitats in Slovenia. Through analyses of landscape-forming elements, we confirmed the differentiation of populations and determined also genetic and morphological differences. For endangered species, who are losing their habitat due to anthropogenic activities or natural disasters it is crucial to define conservation guidelines. For the studied indicator species we defined Slovenian populations as a single evolutionary significant unit. Additionally, we proposed management units for each of the four Slovenian mezzoregions where species occurs.