Shigella is a genus of highly adapted bacterial pathogens that cause bacillary dysentery in humans. Bacteria reaching the colon invade intestinal epithelial cells by a process of bacterial-directed endocytosis mediated by the Ipa proteins: IpaB, IpaC, and IpaD of Shigella. The invasion of epithelial cells is thought to be a receptor-mediated phenomenon, although the cellular components of the h...

The goal of this paper is to investigate the flux and spectral index distribution FR II radio galaxy 4C 14.11. We focused on indices over lobes, as well in their hot spots. For that purpose, we used publicly available observations given at 1450 8440 MHz. Particularly, Leahy's Atlas radio-emitting double sources, Jodrell Bank Centre for Astrophysics Manchester, NASA/IPAC Extragalactic Database. ...

This paper presents a case study of an approach to sustainable software architecture that has been successfully applied over a period of 10 years to astronomy software services at the NASA Infrared Processing and Analysis Center (IPAC), Caltech (http://www.ipac.caltech.edu). The approach was developed in response to the need to build and maintain the NASA Infrared Science Archive (http://irsa.i...

We have previously cloned two distinct regions of the Shigella sonnei form I plasmid pSS120, a 37-kilobase-pair DNA region and a virF region, which were found to be essential for cell invasion in Escherichia coli K-12 (J. Kato, K. Ito, A. Nakamura, and H. Watanabe, Infect. Immun. 57:1391-1398, 1989). The 37-kilobase-pair DNA region was randomly inserted by use of transposon Tn3-lac. At least ei...

We include new data in an updated analysis of helium in low metallicity extragalactic H II regions with the goal of deriving the primordial abundance of He (YP). We show that the new observations of Izotov et al. (ITL) are consistent with previous data. However they should not be taken in isolation to determine YP due to the lack of sufficiently low metallicity points. We use the extant data in...