Many bundle gerbes constructed in practice are either infinite-dimensional, or finite-dimensional but built using submersions that far from being fibre bundles. Murray and Stevenson proved on simply-connected manifolds, bundles with connected fibres, always have a torsion $DD$-class. In this note I prove an analogous result for wide class of principal bundles, relaxing the requirements fundamen...

We describe a technique which permits a uniform construction of a number of low rank bundles, both known and new. In characteristic two, we obtain rank two bundles on P5. In characteristic p, we obtain rank two bundles on P4 and rank three bundles on P5. In arbitrary characteristic, we obtain rank three bundles on P4 and rank two bundles on the quadric S5 in P6.

Combinatorial vector bundles, or matroid bundles, are a combinatorial analog to real vector bundles. Combinatorial objects called oriented matroids play the role of real vector spaces. This combinatorial analogy is remarkably strong, and has led to combinatorial results in topology and bundle-theoretic proofs in combinatorics. This paper surveys recent results on matroid bundles, and describes ...

In the tomato plant water flows through primary xylem in accordance with Poiseuille's law. This relation and the analogy between Poiseuille's and Ohm's law were employed to calculate rates of flow and differences in pressure within vascular bundles when transpiration rates from individual leaves were known. The resistance of vascular bundles to flow was calculated from a modification of Poiseui...