neuromelanin (nm) pigment accumulates with age in catecholaminergic neurons in man, and the ventral substantia nigra dopaminergic neurons that are the most vulnerable to degeneration in parkinson's disease (pd) contain the greatest amount of this pigment. in vitro data indicate that nm pigment is formed from the excess cytosolic catecholamine that is not accumulated into synaptic vesicles via t...

introduction: oxytocin is a active neuropeptide of central nervous system. in this study the effects of naloxone (opioid receptor antagonist) and yohimbine (α-2 adrenergic receptor antagonist) on analgesic effect of oxytocin applied into the locus coeruleus (lc) nucleus were investigated. methods: adult male wistar rats were used. animals divided into different groups receiving saline, oxytocin...

We report characteristics of himA mutations of E. coli, selected for their inability to support the sitespecific recombination reaction involved in the formation of lysogens by bacteriophage X. The himA allele lies at minute 38 on the chromosome. Three noncomplementing and closely linked mutations define the himA locus; one is a nonsense mutation which shows that the gene product is a protein. ...

In this paper, we study the birational geometry of the Hilbert scheme of points on a smooth, projective surface, with special emphasis on rational surfaces such as P2,P1 × P1 and F1. We discuss constructions of ample divisors and determine the ample cone for Hirzebruch surfaces and del Pezzo surfaces with K2 ≥ 2. As a corollary, we show that the Hilbert scheme of points on a Fano surface is a M...

Let G be a connected semisimple algebraic group, B a Borel subgroup, T a maximal torus in B with Weyl group W , and Q a subgroup containing B. For w ∈ W , let XwQ denote the Schubert variety BwQ/Q. For y ∈ W such that XyQ ⊆ XwQ, one knows that ByQ/Q admits a T -stable transversal in XwQ, which we denote by NyQ,wQ. We prove that, under certain hypotheses, NyQ,wQ is isomorphic to the orbit closur...

This paper presents the procedures and findings of a systematic review of research on the impact of testing on students’ motivation for learning. The review was undertaken to provide evidence in relation to claims that, on the one hand, testing raises standards and, on the other, that testing, particularly in high stakes contexts, has a negative impact on motivation for learning that militates ...

This investigation aimed to study polymorphism of growth hormone (GH), growth hormone receptor (GHR), and insulin like growth factor 1 (IGF-1) genes and their associations with growth and carcass traits in Mazandaran native chicken. 200 male chicks were reared and slaughtered at 12 weeks of age. Traits including live weight at 4, 8 and 12 weeks of age, body weight and weights of heart, liver, g...