Before a president practically begins his four-year term of office in Iran, a formal inaugural ceremony is held in the parliament. Being attended by national dignitaries and representatives from other countries, the inauguration of Iran's seventh president, Hasan Rouhani, was spectacular in several respects. The current study aimed at investigating the generic structure and rhetorical moves tha...

We introduce a notion of cross-flips: local moves that transform a balanced (i.e., properly (d + 1)-colored) triangulation of a combinatorial d-manifold into another balanced triangulation. These moves form a natural analog of bistellar flips (also known as Pachner moves). Specifically, we establish the following theorem: any two balanced triangulations of a closed combinatorial d-manifold can ...

In the first part of the paper we recall the coalgebraic approach to handling the so-called invisible transitions that appear in different state-based systems semantics. We claim that these transitions are always part of the unit of a certain monad. Hence, coalgebras with internal moves are exactly coalgebras over a monadic type. The rest of the paper is devoted to supporting our claim by study...

Sokoban is a game on an integer grid, where a warehouse keeper, or robot, has to push boxes to designated storage locations. He can push a box one cell horizontally or vertically if the destination cell is free. Some of the grid cells can be occupied by unmovable obstacles. Several variants of Sokoban have been studied. In these variants all obstacles may be movable, the keeper may push up to k...

As the performance of electronic tracking devices improves dramatically, their use opens up new areas of investigation. The movements of individuals can be linked to physiology, environmental conditions and group behaviour, report back on otherwise inaccessible parts of the biosphere, and warn us of disease spread and natural disasters. Michael Gross reports.

Consider a finite sequence of permutations of the elements 1, . . . , n, with the property that each element changes its position by at most 1 from any permutation to the next. We call such a sequence a tangle, and we define a move of element i to be a maximal subsequence of at least two consecutive permutations during which its positions form an arithmetic progression of common difference +1 o...