The aerial part of Equisetum telmateia Ehrh. is used against various conditions including stomachache and peptic ulcer in Turkish folk medicine. In order to prove the claimed anti-ulcerogenic potential of the plant, aqueous and methanol extracts were prepared from aerial parts of E. telmateia and investigated for their anti-ulcerogenic effect on ethanol-induced gastric ulcer model in rats. Phar...

The extent of near-surface permafrost, or perennially frozen ground within 3m of the surface, was estimated for the Mackenzie River delta by determining its association with riparian vegetation communities in the field, and by subsequently mapping these vegetation communities using SPOT-5 data and the supervised maximum-likelihood classification technique. Near-surface permafrost was absent ben...

Nonphotosynthetic cells of higher plants depend on the supply of a carbon substrate, usually sucrose, for cellular metabolism. Typically this sucrose is synthesized in leaves from the products of photosynthesis. Because of the lack of light below ground, roots do not generally photosynthesize (we note the exception of certain mangrove species and members of the Orchidaceae), although many roots...

In the past two decades, molecular systematic studies have revolutionized our understanding of the evolutionary history of ferns. The availability of large molecular data sets together with efficient computer algorithms, now enables us to reconstruct evolutionary histories with previously unseen completeness. Here, the most comprehensive fern phylogeny to date, representing over one-fifth of th...