Fluorescent dye particles as pollen analogues for measuring pollen dispersal in an insect-pollinated forest herb.

In flowering plants, pollen dispersal is often the major contributing component to gene flow, hence a key parameter in conservation genetics and population biology. A cost-effective method to assess pollen dispersal consists of monitoring the dispersal of fluorescent dyes used as pollen analogues. However, few comparisons between dye dispersal and realized pollen dispersal have been performed to validate the method.

atetra, a new software program to analyse tetraploid microsatellite data: comparison with tetra and tetrasat.

Despite the importance of tetraploid species, most population genetic studies deal with diploid ones because of difficulties in analysing codominant microsatellite data in tetraploid species. We developed a new software program-atetra-which combines both the rigorous method of enumeration for small data sets and Monte Carlo simulations for large ones. We discuss the added value of atetra by comparing its precision, stability and calculation time for different population sizes with those obtained from previous software programs tetrasat and tetra.

Noncollinear magnetic hyperfine fields in the Ag spacers of Fe/Ag multilayers.

Nearly perpendicular magnetic hyperfine fields have been observed for the first time in the Ag "spacers" of Fe/Ag multilayers using low temperature nuclear orientation of (110)Ag(m) at 6 mK. At the same time, vibrating sample magnetometry measurements at temperatures down to 4 K have shown the magnetic anisotropy of the Fe to be in plane. The direction of the Ag hyperfine field is thus noncollinear (nearly orthogonal) to the Fe anisotropy.

[Malignant degeneration of the intestine in Crohn's disease].

A woman suffering more than ten years with Crohn disease, makes one day a small intestinal obstruction. She undergoes a laparotomy in which a resection of 30 cm terminal ileum is done. Surprisingly the anatomo-pathologic diagnosis is adenocarcinoma between the Crohn's inflammatory lesions.