Search results for "Urea"
showing 10 items of 888 documents
Comparative investigation of the pollen morphology of Centaurea parlatoris gr. (sect. Dissectae, Compositae) in Sicily
2009
Comparative study of the isozyme variation of genus Centaurea in Sicily and South Italy
2010
Isozyme investigation on some taxa of Mediterranean Centaurea (Compositae)
2009
Genetic variation patterns in some groups of Centaurea (Asteraceae) in Italy
2012
In the current work the data of the isozyme analysis of all the twenty studied Italian Centaurea taxa were compared. They belong to Centaurea parlatoris, C. cineraria, C. tenorei and C. jacea groups. The following parameters of the genetic variability were considered: the total number of the alleles, the mean number of alleles per locus (A), the mean percentage of polymorphic loci (P95), the expected heterozygosity (He) that is a measure of the intra-population diversity, the Wright’s fixation index (F) and inbreeding coefficient (FIS) that are measures for the deviation from the Hardy-Weinberg equilibrium. The present study contributes to insight some aspects of the genetic diversity relat…
Plant Conservation Centres in Sicily: The ‘Valle Maria’ Regional Centre (Godrano, Palermo) and the case study of the rare Centaurea erycina (Asterace…
2017
The role of the ‘Valle Maria’ Regional Centre and its activity in plant conservation thank to the collaboration with the University of Palermo, Dept. STEBICEF is discussed. The case study on propagation of Centaurea erycina, a narrow Sicilian endemic is presented.
Unpublished aspects of hygrophilous wood vegetation from Nebrodi mountains (N-E Sicily)
2021
In this paper we report the results of a study done on the vegetation of hygrophilous woods and shrubs occurring along the sub montane and montane small rivers of the Alcantara watershed located in the Nebrodi Mountains (N-E Sicily). We have described two new associations: Alno glutinosae-Salicetum rubentis and Euonymo europaei-Salicetum lambertianae, both belonging to the class Salici purpureae-Populetea nigrae. The forest association would belong to the alliance Populion albae of the order Populetalia albae, while the shrubs of pebbly streams would give origin to communities that would belong to the alliance Salicion albae of the order Salicetalia purpureae. The study gave the occasion to…
Effect of 2,4-D and 4-CPPU on somatic embryogenesis from stigma and style transverse thin cell layers of Citrus
2002
Callus induction, somatic embryogenesis and plant regeneration were obtained in lemon [Citrus limon (L.) Burm. cv `Femminello'] and sweet orange [C. sinensis (L.) Osb. cv `Washington Navel GS'] from cultures of stigma and style transverse thin cell layer explants [(t)TCLs]. Explants were cultured on 16 different media, based on the nutrients and vitamins of Murashige and Tucker medium (MT) supplemented with different combinations of 2,4-dichlorophenoxyacetic acid (2,4-D) and N-(2-chloro-4-pyridyl)-Nprime-phenylurea (4-CPPU). Sucrose (146 mM) was used as the sole carbon source. Somatic embryos arose from callus at the surface of stigma and style (t)TCLs 3–5 months after culture initiation of…
The molecular structure of N-hydroxyurea
1996
Ab initio calculations were performed on the tautomers and conformers of N-hydroxyurea using a 6-31G** basis set. The minimum-energy structures have been found and the importance of the intramolecular hydrogen bond as the stabilizing factor was pointed out. © 1996 John Wiley & Sons, Inc.
Volatile components from flowers of Centaurea nicaeensis All., C. parlatoris Helder, C. solstitialis L., ssp. schouwii (DC.) Dostàl wild growing in S…
2008
The volatile constituents of the flowerheads of Centaurea nicaeensis All., C. parlatoris Helder and C. solstitialis L. ssp. schouwii (DC.) Dostal were extracted by hydrodistillation and analysed by GC and GC-MS. Altogether 113 components were identified. Fatty acids and hydrocarbons were the most abundant components in the oils. Caryophyllene and caryophyllene oxide were the main compounds of the sesquiterpene fraction. The study on the biological activity of the oils shows no significant activity.
Protesi | Materiali di Design
2015
Le Tesi di Laura, si potrebbe dire, non sono più come una volta. E già, oggi c’è il cosiddetto “elaborato breve”, una cosetta agile per acchiappare al volo l’altrettanto agile “pezzo di carta”: la sempre meno aurea e sempre più aerea Laurea. Eppure, mi chiedo: che se ne fa un (neo)designer della Laurea? Non può iscriversi a un albo, come un architetto o un ingegnere. E poi in Italia quanto vale la Laurea, specialmente quando il 110 e lode è diventato dozzinale? In effetti, non soltanto il massimo dei voti è ormai più che diffuso, ma siamo sicuri che tutti questi designer titolati, e in generale laureati da 110 e lode, abbiano poi idea di come si fa ciò per cui hanno studiato? E ancora: a ch…