For all masses, there are at least n ?2 O 2-orbits of non-collinear planar central conngurations. In particular, this estimate is valid even if the potential function is not a Morse function. If the potential function is a Morse function, then an improved lower bound, on the order of n! ln ? n+1 3 =2, can be given.

Phenylethanolamine N-methyltransferase (PNMT, E.C.2.1.1.28) is the terminal enzyme in the synthesis of adrenaline ill the adrenal medulla 1, other chromaffin tissues, and in the mammalian brain iv. Changes in the level of adrenal and hypothalamic PNM T activity have been correlated with changes in the tissue content of adrenaline 13,15,1s,2°. It is well established that PNMT requires glucocorti...

abstract background: peripheral insertion of central catheters can be difficult in neonates. we compared the success rates of peripherally inserted central catheters by two methods of using static ultrasound and traditional technique (vein visualization and palpation) in neonates. materials and methods: in a prospective randomized, controlled trial, 52 neonates with birth weight lower than 1500...

We present an equivariant extension of the Thom form with respect to a vector field action, in the framework of the Mathai-Quillen formalism. The associated Topological Quantum Field Theories correspond to twisted N = 2 supersymmetric theories with a central charge. We analyze in detail two different cases: topological sigma models and non-abelian monopoles on four-manifolds.

We consider n-body problems given by potentials of the form α r + β r with a, b, α, β constants, 0 ≤ a < b. To analyze the dynamics of the problem, we first prove some properties related to central configurations, including a generalization of Moulton’s theorem. Then we obtain several qualitative properties for collision and near-collision orbits in the Manev-type case a = 1. At the end we poin...

We extend the notion of central charge superspace to the case of local supersymmetry. Gauged central charge transformations are identified as diffeomorphisms at the same footing as space-time diffeomorphisms and local supersymmetry transformations. Given the general structure we then proceed to the description of a particular vector-tensor supergravity multiplet of 24 + 24 components, identifie...

Introduction of ostrich (Struthio camelus domesticus), a new exotic host species to a new ecosystem likeIran, necessitates the study of its infectious diseases including parasitic infestations. For a period of one year, from 2002–03, faecal samples of 254 ostriches on 5 farms located at different parts of Iran, includingGarmsar, Semnan province (n = 85); Nashtaroud, Mazandaran province (n = 29)...