Interactions of electrical and magnetic charges and dark topological defects

We consider a model of dark photon which appears as a result of the successive symmetry breaking SU(2)$\,\to\,$U(1)$\,\to \mathbb{Z}_2$, where various types of topological defects appear in the dark sector. In this paper, we study the interactions between QED charges and the dark topological defects through mixing between QED photon and dark photon. In particular, we extend our previous analysis by incorporating the magnetic mixing and $\theta$-terms. We also consider the dyons and dyonic beads in the dark sector. Notably, dark magnetic/dyonic beads are found to induce a QED Coulomb potential through the magnetic mixing despite finite mass of the dark photon.Comment: 17 pages, 4 figure

Regulation of Morphological and Functional Aspects of Sexual Dimorphism in the Brain

Sexual dimorphism of the adult brain regulates sex-dependent functions including reproductive and neuroendocrine activities in rodents. It is determined by sex steroid hormones during a critical perinatal period in female and male rodents. Sex steroids act on each nuclear receptor in the brain and control different physiological and neuroendocrine functions and behaviors. Several regions of the brain show evident morphological sex differences that are involved in their physiological functions. This review addresses and focuses largely on the role of sex-dependent differences in the brain, and their crucial functions in animal models. Particularly, recent intriguing data concerning the diversity of neuronal functions and sexual dimorphism are discussed

PCR random mutagenesis into Escherichia coli serine acetyltransferase: isolation of the mutant enzymes that cause overproduction of L-cysteine and L-cystine due to the desensitization to feedback inhibition

AbstractPCR random mutagenesis in the cysE gene encoding Escherichia coli serine acetyltransferase was employed to isolate the mutant enzymes that, due to a much less feedback inhibition by L-cysteine, cause overproduction of L-cysteine and L-cystine in the recombinant strains. The L-cysteine auxotrophic and non-utilizing E. coli strain was transformed with plasmids having the altered cysE genes. Then, several transformants overproducing L-cysteine were selected by detecting the halo formation of the L-cysteine auxotroph. The production test of amino acids and analysis of the catalytic property on the mutant enzymes suggest that the carboxy-terminal region of serine acetyltransferase plays an important role in the desensitization to feedback inhibition and the high level production of L-cysteine and L-cystine