Guarding the Genome

Artemis: guarding small children and, now, the genome.

Through careful analysis of young patients exhibiting radiosensitivity and inherited SCID of B and T lymphocytes, Despina Moshous and colleagues discovered a new DNA repair gene two years ago and named it after the Greek goddess Artemis, a guardian of young children and small animals (1). The same group has recently analyzed several patients with hypomorphic Artemis mutations, and their results...

Guarding Art Galleries by Guarding Witnesses

Let P be a simple polygon. We define a witness set W to be a set of points such that if any (prospective) guard set G guards W , then it is guaranteed that G guards P . We show that not all polygons admit a finite witness set. If a finite minimal witness set exists, then it cannot contain any witness in the interior of P ; all witnesses must lie on the boundary of P , and there can be at most o...

Guarding the Body

Guarding the Gate

BACKGROUND Failed treatment trials are common in major depressive disorder and treatment-resistant depression, and remotely performed multifaceted, centralized structured interviews can potentially enhance signal detection by ensuring that enrolled patients meet eligibility criteria. METHODS We assessed the use of a specific remote structured interview that validated the diagnosis, level of t...

Triangle Guarding

We consider the problem of triangle guarding (4-guarding) a simple, 2D polygon Q. A polygon Q is 4-guarded if every point q of Q is contained in the convex hull of some three guards that can all see q. This rather odd condition approximates a desire, for example, to see all sides of q or to locate (via triangulation) q from at least two angularly well-separated views. If we restrict the guards ...