In a group G, we denote the (cyclic) group of powers of some g ∈ G by 〈g〉 = {g : k ∈ Z}. If G = 〈g〉, then G itself is cyclic, with g as a generator. Examples of infinite cyclic groups include Z, with (additive) generator 1, and the group 2Z of integral powers of the real number 2, with generator 2. The most basic examples of finite cyclic groups are Z/(m) with (additive) generator 1 and μm = {z...

AIM To report the effects of greater occipital nerve (GON) blocks on refractory chronic migraine headache. METHODS Nine patients who were receiving the conventionally accepted preventive therapies underwent treatment with repeated GON block to control chronic migraine resistant to other treatments. GON blocking with lidocaine and normal saline mixture was administered by the same physician at...

We prove an embedding theorem that says a convex body can pass through a triangular hole∆ if and only if the convex body can be congruently embedded in a right triangular prism with base ∆. Combining this with a known result on congruent embeddings of a regular tetrahedron in a triangular prism, we show that a regular tetrahedron with unit edge can pass through an equilateral triangular hole in...

| In this paper, we study various algorithmic questions regarding the computation of an optimal three n-ger planar grasp. We present a novel O(n 2 logn)-time algorithm to compute such an optimal grasp for an arbitrary simple n-gon. This algorithm can be used for nding \good" immobilizing sets. We also discuss several variations on the problem and many intriguing open questions in the area that ...