Plasmid topology varies transiently in hyperthermophilic archaea during thermal stress. As in mesophilic bacteria, DNA linking number (Lk) increases during heat shock and decreases during cold shock. Despite this correspondence, plasmid DNA topology and proteins presumably involved in DNA topological control in each case are different. Plasmid DNA in hyperthermophilic archaea is found in a topo...

The cold-shock domain has a deceptively simple architecture but supports complex biology. It is conserved from bacteria to man and representatives in all kingdoms of life. Bacterial proteins consist single some, not are induced by cold shock. Cold-shock domains human often associated with natively unfolded protein segments more rarely other folded domains. share five-stranded all-antiparallel ?...

Dense Silicon nitride was investigated to determine the effect of its microstructural parameters and densification on thermo-mechanical properties and thermal stress resistance to fracture initiation during a hot or cold mechanical and thermal shock testing. The different materials and microstructures were obtained by changing the parameters such as the type of the powder, additive, forming p...

The ability to modify RNA secondary structure is crucial for numerous cellular processes. We have characterized two RNA helicase genes, crhB and crhC, which are differentially expressed in the cyanobacterium Anabaena sp. strain PCC 7120. crhC transcription is limited specifically to cold shock conditions while crhB is expressed under a variety of conditions, including enhanced expression in the...

Transfer of Enterococcus faecalis to a cold temperature (8 degrees C for 4 to 30 h) led to increased expression of 11 cold shock proteins (CSPs). Furthermore, this mesophilic prokaryote synthesized 10 cold acclimation proteins, five of them distinct from CSPs, during continuous growth (4 days) at the same temperature (8 degrees C).

We present general relativistic solutions for self-similar spherical perturbations in an expanding cosmological background of cold pressure-less gas. We focus on solutions having shock discontinuities propagating in the surrounding cold gas. The pressure, p, and energy-density, μ, in the shock-heated matter are assumed to obey p = wμ, where w is a positive constant. Consistent solutions are fou...