The new DEVS-NS2 modeling and simulation environment supports both high and low levels of abstraction network modeling and simulation. DEVS (Discrete Event System Specification) is a well-defined mathematical formalism specification for structure and behavior of dynamic systems. The NS-2 is a discrete event network simulator, whose primary use is intended to build and run various detailed netwo...

BACKGROUND For potential future human missions to the Moon or Mars and sustained presence in the International Space Station, a safe enclosed habitat environment for astronauts is required. Potential microbial contamination of closed habitats presents a risk for crewmembers due to reduced human immune response during long-term confinement. To make future habitat designs safer for crewmembers, l...

Halophilic and halo-tolerant bacteria are micro-organisms that living in hyper saline environments. They have many potential several fields life such as Industry agriculture. In this study a total of 17 isolates were obtained from the four ponds Qarun Lake on Nutrient Agar (NA) medium prepared using ponds' water. The 16S rRNA analysis showed our affiliated with groups, Firmicutes (47.06% isolat...

Cloned nitrogen fixation (nifl) genes from Klebsiella pneumoniae hybridize to DNA from 19 out of 19 widely divergent nitrogen-fixing bacterial strains but do not hybridize to DNA from 10 different non-nitrogen-fixing species. K pneumoniae nifDNA fragments that hybridize to DNA from other species contain part of the three structural genes that code for nitrogenase polypeptides. We have utilized ...

Cloned nitrogen fixation (nifl) genes from Klebsiella pneumoniae hybridize to DNA from 19 out of 19 widely divergent nitrogen-fixing bacterial strains but do not hybridize to DNA from 10 different non-nitrogen-fixing species. K pneumoniae nifDNA fragments that hybridize to DNA from other species contain part of the three structural genes that code for nitrogenase polypeptides. We have utilized ...

For functional characterization of genes, it is often interesting to identify additional upor downstream sequences in a fast and inexpensive way. Constructing a phage λ or cosmid library is time consuming, and subcloning of the corresponding fragments has to be performed to isolate DNA that can be sequenced (3). Alternative methods such as inverse PCR (2) or onesided PCR (4) have been developed...