recurrent sigmoid volvulus is a clinical entity characterized by recurrent episodes of partial or complete sigmoid volvulus. although it is commonly seen in the elderly, it can be occasionally seen in younger patients. patients with recurrent partial sigmoid volvulus are relatively asymptomatic or present with mild abdominal pain. early diagnosis and treatment is essential to prevent conversion...

In continuation of [JOH04, OH07], we prove that existentially closed CSA-groups have the independence property. This is done by showing that there exist words having the independence property relative to the class of torsion-free hyperbolic groups.

The theory of abelian totally ordered groups has a model completion. We show that the theory of abelian lattice-ordered groups has no model companion. Indeed, the Archimedean property can be captured by a first order V3V sentence for existentially complete abelian lattice-ordered groups, and distinguishes between finitely generic abelian lattice-ordered groups and infinitely generic ones. We th...

We extend results of Denef, Zahidi, Demeyer and the second author to show the following. (1) Rational integers have a single-fold Diophantine definition over the ring of integral functions of any function field of characteristic 0. (2) Every c.e. set of integers has a finite-fold Diophantine definition over the ring of integral functions of any function field of characteristic 0. (3) All c.e. s...

Signcryption is a cryptographic primitive that provides authentication and confidentiality simultaneously in a single logical step. It is often required that multiple senders have to signcrypt a single message to a certain receiver. Obviously, it is inefficient to signcrypt the messages separately. An efficient alternative is to go for multi-signcryption. The concept of multi-signcryption is si...