Not in at the moment
buy sucralfate online Sandhage and graduate student Brandon Goodwin began by examining the microscopic shapes of several types of pollen – including ragweed, pecan and dandelion – before choosing particles from the sunflower (Helianthus annuus). The sunflower pollen grains are nearly spherical, but covered with spikes that can entangle with the hairs on bees' legs, or adhere to surfaces via van der Waals forces at nanometer-scale distances, Sandhage explained.