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Karyotype structures revealed by in situ hybridization with ribosomal and satellite DNAs and fluorochrome staining of AT- or GC-rich regions are reported for 23 diploid to tetraploid taxa of Aveneae genera Arrhenatherum, Avena, Helictotrichon, and Pseudarrhenatherum. Chromosomal features are compared with a molecular phylogeny generated on nuclear ribosomal (ITS, SS) and chloroplast (matK) DNA sequences. Ancestral chromosomal character states are (1) two satellite chromosomes per set of x = 7, (2) SS rDNA localized in nonsatellite chromosomes, (3) large chromosomes with (4) rather equal lengths of their respective chromosome arms, (5) sets with strong variance of chromosome lengths, (6) absence or small amounts of heterochromatin, and (7) absence or no detectable amplification of the satellite DNAs tested. Overall, most karyotype characteristics are species specific, but common patterns were found for the species of two large subgenera of Helictotrichon. Pseudarrhenatherum, although nested in the molecular phylogeny within Helictotrichon subgenus Helictotrichon, deviates strongly in karyotype characters such as Arrhenatherum as sister of Avena. The karyotype of Helictotrichon jahandiezu, sister to the Glade of Helictotrichon subgenera Helictotrichon, Avena, and Arrhenatherum, strongly resembles that of Avena macrostachya. Karyotype features suggest that perennial A. macrostachya and H. jahandiezu are close to the C-genome species of annual Avena, whereas the Avena A genome resembles that of Arrhenatherum. Key words: karyotypes, chromosome evolution, molecular phylogeny, Poaceae, Aveneae, FISH, rDNA, matK. Les caryotypes reveles par hybridation in situ a l'aide de sondes ribosomiques ou d'ADN satellites ainsi que pat coloration des regions riches en AT ou GC a f aide de fluorochromes sont rapportes pour 23 taxons diploides ou tetraploides au sein des genres Arrhenatherum, Avena, Helictotrichon et Pseudarrhenatherum de la famine des avenacees. Les caracteristiques chromosomiques sont compaees avec une phylogenie moleculaire basee sur des sequences d'ADN ribosomiques (ITS, SS) et chloroplastiques (matK). La forme chromosomique ancestrale est caracterisee par (1) la presence de deux chromosomes satellites par jeu de x = 7 chromosomes, (2) la localisation de fADNr SS sur des chromosomes non-satellites, (3) des grands chromosomes, (4) ces derniers ayant des bras chromosomiques de tailles egales, (5) une variabilite considerable quant a la longueur des chromosomes chez certains jeux, (6) (absence ou une faible quantite d'heterochromatine et (7) (absence ou l'impossibilite de detecter des ADN satellites testes. Globalement, la plupart des caracteristiques etaient specifiques de fespece, mais certains aspects en common ont ete releves chez les especes appartenant a deux grands sous-genres de Helictotrichon. Pseudoarrhenotherum, bien que loge au sein du Helictotrichon sousgenre Helictotrichon sur la base de la phylogenie moleculaire, se distinguait nettement sur la base du caryotype tout comme l'Arrhenatherum suppose proche du genre Avena. Le caryotype du Helictotrichon jahandiezu, taxon proche du Glade comprenant Helictotrichon sousgenres Helictotrichon, Avena et Arrhenatherum, affichait une grande resemblance avec celui de l'Avena macrostachya. Les caracteristiques caryotypiques suggerent que les especes perennes A. macrostachya et H. jahandiezu sont proches des especes annuelles d'Avena a genome C, tandis que le genome A des Avena ressemble a celui des Arrhenatherum. Mots-cles : caryotypes, evolution des chromosomes, phylogenie moleculaire, poacees, avenacees, FISH, ADNr, matK. [Traduit par la Redaction], Introduction The tribe Aveneae as delineated in current taxonomic treatments represents one of the major lineages of grasses in the Northern Hemisphere and comprises roughly 60-80 genera (Clayton and Renvoize [...]

The article explains the parallel evolutionary patterns, as well as the other traits that are observed in the multiple lineages of Arctic Artemisia l. (Asteraceae). The plant height was shown to have considerably reduced in the Arctic lineages with repeated evolution of the enlarged flower heads.

Objective: The clinical practice concerning the use of coercive measures in psychiatry should be compared., Method: A common documentation of physical restraint, seclusion, and medication by coercion was introduced among 10 hospitals., Results: 8.4 % of cases treated within the first 6 months of 2004 were exposed to coercive measures with the highest percentage among patients with psychoorganic disorders (32.1 %). The incidence of coercive measures varied highly between different diagnostic groups and hospitals., Discussion: The processing of the large multi-site data sets yields considerable technical problems. Data interpretation should consider confounding factors such as case mix and hospital structure characteristics.