Alpine vegetation is scarce in central Mexico (≈150 km2) and occurs on the 11 highest peaks of Trans-Mexican Volcanic Belt (TMVB). Timberline at (3700) 3900 m, 4750 m vascular plants cease to exist. The alpine flora comprises 237 species from 46 families 130 genera. Asteraceae (44), Poaceae (42), Caryophyllaceae (21) possess 45% species; none remaining have more than 10 species. Four are strict...

The Cameroon Volcanic Line (CVL) of west Africa poses many challenges to common models mantle processes and volcanic system genesis. Although the CVL superficially resembles hot-spot trace a plume, there is no evidence for age progression initiation or cessation activity, making one several hot-lines observed on Earth, which exhibit asynchronous volcanism along each line. This unusual form syst...

More than 50 conspicuous tephra beds occur in the Kanguk Formation of SW Banks Island. Their glass shards are remarkably well preserved and permit comprehensive characterization offering potential for reliable, precise correlation Upper Cretaceous sedimentary rocks across three major depocentres Arctic Archipelago adjacent northern continental margin: Sverdrup, Banks, Beaufort-MacKenzie basins....

Belt-positioning booster seats are recommended for children who use vehicle seat belts as primary restraints but who are too small to obtain good belt fit. Previous research has shown that belt-positioning boosters reduce injury risk, but the belt fit produced by the wide range of boosters in the US market has not previously been assessed. The present study describes the development of a method...