Molecular data and ploidal levels indicate several putative allopolyploidization events in the genus Potentilla (Rosaceae).

Several naturally occurring hybrids in Potentilla (Rosaceae) have been reported, but no molecular evidence has so far been available to test these hypotheses of hybridization. We have compared a nuclear and a chloroplast gene tree to identify topological incongruences that may indicate hybridization events in the genus. Furthermore, the monophyly and phylogenetic position of the proposed segregated genera Argentina, Ivesia and Horkelia have been tested.

Allopolyploidy in Fragariinae (Rosaceae): comparing four DNA sequence regions, with comments on classification.

Potential events of allopolyploidy may be indicated by incongruences between separate phylogenies based on plastid and nuclear gene sequences. We sequenced two plastid regions and two nuclear ribosomal regions for 34 ingroup taxa in Fragariinae (Rosaceae), and six outgroup taxa. We found five well supported incongruences that might indicate allopolyploidy events.

Improved estimation and visualization of two-dimensional myocardial strain rate using MR velocity mapping.

Purpose: To estimate regional myocardial strain rate, with reduced sensitivity to noise and velocities outside the region of interest, and provide a visualization of the spatial variation of the obtained tensor field within the myocardium.

Materials And Methods: Myocardial velocities were measured using two-dimensional phase contrast velocity mapping. Velocity gradients were estimated using normalized convolution and the calculated 2D strain rate tensor field was visualized using a glyph representation.

Treatment of osteochondral defects with autologous bone marrow in a hyaluronan-based delivery vehicle.

The natural repair of osteochondral defects can be enhanced with biocompatible, biodegradable and bioactive materials that provide structural support and molecular cuing to stimulate repair. Since bone marrow contains osteochondral progenitor cells and bioactive agents, it is hypothesized that the combination of scaffold and bone marrow would be a superior composite material for osteochondral repair. This hypothesis will be tested by comparing the outcome of osteochondral defects filled with a fibronectin-coated hyaluronan-based sponge (ACP) with or without autologous bone marrow.