Borders are a man made institution, and as such their shape cannot be taken as part of the physical landscape. The size of countries is endogenous to politico economic forces. This paper discusses recent efforts by economists to study three related question: what determines the evolution of the size of countries? Does size matter for economic success? Given the trend toward decentralization and...

Borders are a man-made institution, and as such their shape cannot be taken as part of the physical landscape. The size of countries is endogenous to politico-economic forces. This paper discusses recent efforts by economists to study three related questions: What determines the evolution of the size of countries? Does size matter for economic success? Given the trend toward decentralization an...

N-Ethylmaleimide-sensitive fusion protein (NSF) is an ATPase required in multiple stages of the secretory and endocytic pathways. NSF requires other proteins for its action in vesicular transport including the soluble NSF attachment proteins (SNAPs), which act to bind NSF to integral membrane proteins. We have investigated the ATPase activity of NSF and its modulation by alpha- and gamma-SNAPs ...

A case of intestinal bleeding caused by multiple ulcerations near the terminal ileum is presented. Abdominal scanning with Tc-99m tagged red blood cells (Tc-99m RBC) demonstrated the intermittent bleeding in short intervals. Selective angiography did not demonstrate the bleeding site. Exploratory laparotomy showed 3 ulcers on the ileum at a site near the terminal ileum, with bleeding from one s...

We establish basic properties of cluster algebras associated with oriented bordered surfaces with marked points. In particular, we show that the underlying cluster complex of such a cluster algebra does not depend on the choice of coefficients, describe this complex explicitly in terms of “tagged triangulations” of the surface, and determine its homotopy type and its growth rate.

Prion diseases are fatal neurodegenerative disorders with unique transmissible properties. The infectious and pathological agent is thought to be a misfolded conformer of the prion protein. Little is known about the initial events in prion infection because the infecting prion source has been immunologically indistinguishable from normal cellular prion protein (PrP(C)). Here we develop a unique...

The pathogenesis of neurodegenerative diseases is believed to involve abnormal aggregation of proteins, but the mechanisms initiating protein aggregation are unclear. Here we report a novel phenomenon that could be instrumental in triggering protein aggregation in neurodegenerative diseases. We show that the 3' untranslated region (3'UTR) of a light neurofilament (NF-L) transcript enhances the ...