We study compact non-supersymmetric Z N orbifolds in various dimensions. We compute the spectrum of several tachyonic type II and heterotic examples and partially classify tachyon-free heterotic models. We also discuss the relation to compactification on K3 and Calabi-Yau manifolds.

conclusions these data will be beneficial for designing more advanced antibodies for the recognition of the hbsag in diagnostics. in addition, the results of this study may assist in the design or development of more effective hepatitis b vaccines. results the g145r mutation causes a considerable reduction in the immunogenic activity of the hbsag through a conformational change in the hbsag ant...

abstract       background and objective: hepatitis b virus (hbv) is a dna virus with high tendency toward hepatic tissue. there are currently about 3 million hbv-infected people and 350 to 400 million chronic carriers of this virus in the world. x protein plays a role in the over-expression of oncogenes, carcinogenicity of liver cells and overlaps with the basal core promoter of the virus. muta...

It is well-known that an effective orbifold M (one for which the local stabilizer groups act effectively) can be presented as a quotient of a smooth manifold P by a locally free action of a compact lie group K. We use the language of groupoids to provide a partial answer to the question of whether a noneffective orbifold can be so presented. We also note some connections to stacks and gerbes.

We derive anomaly constraints for Abelian and non-Abelian discrete symmetries using the path integral approach. We survey anomalies of discrete symmetries in heterotic orbifolds and find a new relation between such anomalies and the socalled ‘anomalous’ U(1).

We formulate the effective field theory of a D-particle on orbifolds of T 4 by a cyclic group as a gauge theory in a V -bundle over the dual orbifold. We argue that this theory admits Fayet-Iliopoulos terms analogous to those present in the case of noncompact orbifolds. In the n = 2 case, we present some evidence that turning on such terms resolves the orbifold singularities and may lead to a K...

how to cite this article: tonekaboni sh, ebrahimi a, bakhshandeh bali mk, houshmand m, moghaddasi m, taghdiri mm, nasehi mm. sodium channel gene mutations in children with gefs + and dravet syndrome: a cross sectional study. iran j child neurol. 2013 winter; 7 (1):25-29.   objective dravet syndrome or severe myoclonic epilepsy of infancy (smei) is a baleful epileptic encephalopathy that begins ...

conclusions presence of drug resistance mutations among the patients was significant. precore mutations were common amongst iranian hbv chronic carriers under lamivudine therapy and these mutations were accompanied by clinical relapse. patients and methods sequential sera were obtained from 88 chronic hbv carriers who received lamivudine for more than 24 months. polymerase and precore regions w...

neonatal diabetes mellitus (ndm) is a rare kind of diabetes characterized by hyperglycemia and low levels of insulin. clinically, it is categorized into two main types: transient ndm (tndm) and permanent ndm (pndm). these types are diagnosed based on duration of insulin dependence early in the disease. in tndm, diabetes begins in the first few weeks of life with remission in a few months. howev...