Trees stumped

Problems that stumped me

Here, subgroups of = G(Z) are called congruentially conjugate if their images in G(Z=mZ) are conjugate for each m 2 N (where G is a linear algebraic group de…ned over Q). The result (b) is proved in [GS] using respectable mainstream mathematics (…niteness properties of arithmetic groups, due to Borel and Serre). Problem 1 is to …nd a natural and attractive way to do (a); the existing proof is m...

Nerve Regeneration: Regrowth Stumped by Shared Receptor

Three different myelin proteins, Nogo, MAG, and OMgp, inhibit regenerating axons after CNS injury. New work reveals that they all share a common receptor and that blockade of this receptor promotes CNS repair and functional recovery.

HEALTHY BABY ‘Stumped’ by the Newborn Umbilical Cord

Practical advice for treating newborns and toddlers. ‘Stumped’ by the Newborn Umbilical Cord

The postnatal management for the newborn umbilical cord is surprisingly controversial. Numerous investigators have explored the optimal approach to cord care, whether it is performed during the first 24 hours of life, or in the first weeks of life until the cord spontaneously separates from the body. The average length of cord retention varies from 3 to 45 days, with a mean separation time of 1...

One-Sided Interval Trees

We give an alternative treatment and extension of some results of Itoh and Mahmoud on one-sided interval trees. The proofs are based on renewal theory, including a case with mixed multiplicative and additive renewals.