Many questions in evolutionary biology require an estimate of divergence times but, for groups with a sparse fossil record, such estimates rely heavily on molecular dating methods. The accuracy of these methods depends on both an adequate underlying model and the appropriate implementation of fossil evidence as calibration points. We explore the effect of these in Poaceae (grasses), a diverse p...

BACKGROUND Few studies have used time series to investigate the relationship between asthma attacks and aeroallergen levels on a daily basis. METHODS This study, based on time series analysis adjusting for meteorological factors and air pollution variables, assessed the short term effects of different types of allergenic pollen on asthma hospital emergencies in the metropolitan area of Madrid...

An Evaluation of the Invasive Potential of Beach Vitex (Vitex rotundifolia) Charles A. Gresham and Amber Neal The Belle W. Baruch Institute of Coastal Ecology and Forest Science, Clemson University P. O. Box 596, Georgetown, SC 29442 ABSTRACT This study was conducted to determine if the introduced woody plant Beach Vitex, Vitex rotundifolia (Verbenaceae), (BV), has the potential to displace nat...

The aim of the study was to determine the length of Poaceae pollen season, intradiurnal, daily and monthly pollen variation, and the effect of some meteorological parameters on atmospheric pollen concentration, at three monitoring sites in inland Croatia during the 2003-2004 period. Seven-day Hirst volumetric pollen and spore traps were used for pollen sampling. At all three monitoring sites co...

The adult female and first-instar nymph of a new species of armoured scale insect, Poliaspoides bambusae sp.n. (Diaspididae), is described and illustrated. The new species was collected in Turkey on imported ornamental Bambusa siamensis (Poaceae) from an unknown source.

this recent study documents the phenolic constituents of the triticum l. species in iran using thinlayer chromatography. species studied are related to 55 wild and cultivated accessions of four diploid andfour tetraploid species, namely triticum boeoticum subsp. boeoticum boiss., t. boeoticum subsp. thaoudarreut. ex boiss., t. monococcum l., t. urartu tum. ex gand., t. turgidum l., t. dicoccoid...