Heteropoly acid-catalyzed microwave-assisted three-component aza-Diels-Alder cyclizations: diastereoselective synthesis of potential drug candidates for Alzheimer's disease.

A highly diastereoselective microwave-assisted three component synthesis of azabicyclo[2.2.2]octan-5-ones by a silicotungstic acid-catalyzed aza-Diels-Alder cyclization is described.

Ultrastructural analysis supports transferring Nosema whitei Weiser 1953 to the genus Paranosema and creation a new combination, Paranosema whitei.

The current ultrastructural description of Nosema whitei is in agreement with the genus definition of Paranosema [Sokolova, Y.Y., Dolgikh, V.

Establishment of the new genus Paranosema based on the ultrastructure and molecular phylogeny of the type species Paranosema grylli Gen. Nov., Comb. Nov. (Sokolova, Selezniov, Dolgikh, Issi 1994), from the cricket Gryllus bimaculatus Deg.

The ultrastructure of the microsporidian parasite Nosema grylli, which parasitizes primarily fat body cells and haemocytes of the cricket Gryllus bimaculatus (Orthoptera, Gryllidae) is described. All observed stages (meront, meront/sporont transitional stage ("second meront"), sporont, sporoblast, and spore) are found in direct contact with the host cell cytoplasm. Nuclei are diplokaryotic during almost all stages of the life cycle, but a brief stage with one nucleus containing an abundance of electron-dense material is observed during a "second merogony.

Four developmental stages identified by genetic dissection of pea (Pisum sativum L.) root nodule morphogenesis.

Root nodule structural organisation of nine pea Fix(-) mutants representing seven symbiotic loci has been studied. This set of mutants has revealed lesions at four developmental stages in the pea-Rhizobium symbiosis. (i) Mutant RisFixA is affected in infection thread differentiation in nodule tissue, infection droplet formation, bacteroid differentiation and nodule persistence.