Ecological continuity and transformation after the Permo-Triassic mass extinction in northeastern Panthalassa.

The Permo-Triassic mass extinction (PTME) is often implicated in the transition from the Paleozoic evolutionary fauna (PEF) to the modern evolutionary fauna (MEF). However, the exact timing and details of this progression are unknown, especially regarding the vacating and filling of functional ecological space after the PTME. Here, we quantify the functional diversity of middle Permian and Early Triassic marine paleocommunities in the western US to determine functional re-organization in the aftermath of the PTME.

Detection of M. tuberculosis DNA using thermophilic strand displacement amplification.

Strand Displacement Amplification (SDA) is an isothermal, in vitro method of amplifying DNA that is based upon the combined action of a DNA polymerase and restriction enzyme. Previously, a form of SDA was developed which utilizes the exonuclease deficient Klenow fragment of E. coli polymerase I (exo Klenow) and the restriction enzyme HincII to achieve 10(8)-fold amplification in 2 h at 37 degrees C (Walker, G.

Strand displacement amplification--an isothermal, in vitro DNA amplification technique.

Strand Displacement Amplification (SDA) is an isothermal, in vitro nucleic acid amplification technique based upon the ability of HincII to nick the unmodified strand of a hemiphosphorothioate form of its recognition site, and the ability of exonuclease deficient klenow (exo- klenow) to extend the 3'-end at the nick and displace the downstream DNA strand. Exponential amplification results from coupling sense and antisense reactions in which strands displaced from a sense reaction serve as target for an antisense reaction and vice versa. In the original design (G.

Incidence of Salmonellae in Clams, Oysters, Crabs and Mullet .

Sixty samples each of oysters ( Crassostrea virginica ), clams ( Mercenaria mercenaria ), striped mullet ( Mugil cephalus ), and blue crab ( Callinectes sapidus ) were analyzed for the presence of salmonellae within 4 h of harvesting from an east and west coast location in Florida. Mullet was the only seafood from which salmonellae were not recovered. Clams from the west coast location had the highest incidence (43%) of salmonellae.