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The morphology and variability of pollen of Rosa pendulina L. were studied. The material came from 10 native localities of this species. 300 pollen grains were examined. It was established that the diagnostic features of pollen grains of R. pendulina L. were: an elongated, narrow operculum, a poorly developed exine sculpture, long ectocolpi (a low value of the apocolpium index), and the predominance of grains elongated in shape. The results obtained usually correspond to data supplied by other palynologists. A statistical analysis of 10 quantitative grain characteristics showed their variability to be rather low. The highest variability was found to occur in two traits connected with d (the distance between the apices of two ectocolpi). Statistical studies revealed dependences among the grains from the 10 analysed localities
Seven triticale cultivars (Ampiac, Aubrac, Trinidad, Ticino, Lamberto, Pronto and Prado) and their F1 hybrids obtained after crossing in a line x tester scheme were examined with respect to their androgenetic effectiveness. The embryo induction rate (number of embryos per 100 anthers), green plant regeneration rate (number of green plantlets per 100 embryos), plant yield (number of green and albino plantlets per 100 anthers) and green plant yield (number of green plantlets per 100 anthers) were assessed. The multivariate and univariate effects of general (GCA) and specific (SCA) combining abilities for the studied traits were estimated and tested. Significant differences between the genotypes were found for individual traits as well as for all the traits treated jointly. Hybrids generally showed a better response in anther culture than their parental genotypes. Heterosis effects were observed in some hybrids for embryo induction rate and green plant yield. GCA and SCA variances were significant and a dominance of the GCA over the SCA variation was found. Among the examined cultivars, Ticino and Pronto were characterised by positive and significant GCA for embryo induction and green plant yield, and these cultivars may be recommended for the improvement of anther culture responsiveness in triticale.
A recent paper on the occurrence of the genus Crocidura in Tunisia reports a single specimen identified as C. suaveolens. Therefore a third species, besides C. russula and C. whitakeri would occur in the country. However, the presence of C. suaveolens in North-Africa is controversial and was recently ruled out from the other Maghrebi countries (Algieria and Morocco). During the period 1989 - 90, 71 specimens of shrews were collected from owls pellets or trapped at Tunisian 12 sites. This material was measured and studied both by classic morphometric and multivariate methods (Fuzzy test, Principal Coordinate Analysis and Generalized Procrustes Analysis), considering also reference samples (C. suaveolens from Italy and Balearic Islands, C. russula and C. whitakeri from Morocco). Four of the 12 trapped shrews were karyotyped and resulted to have a C. russula karyotype, some differences in biometry as well as in Number of Fundamental arms (NFa) separate the Moroccan population from the Tunisian one and raise some interesting questions on the taxonomy of C. russula. Multivariate analysis also allowed us to exclude the presence of C. suaveolens from the Tunisian material studied and suggested also the misclassification of the proposed specimen that should be reconsidered as C. whitakeri. A preliminar distribution map of the two species living in Tunisia was drawn, also based on the scanty data from the literature.
The observational study was carried out in a population of Polish breeding goats in 2007 to determine the prevalence of fetal loss and identify risk factors contributing to its occurrence. The multivariate model allowing to predict the risk of the occurrence of fetal loss in a herd in a study population was developed. Data on the occurrence of fetal loss, as well as of 28 hypothesized risk factors were collected from goat owners using standardized questionnaire during face-to-face reviews on farms. Moreover, data on the herd-level seroprevalence of four abortifacient infections – Chlamydophila abortus, Leptospira spp., BVDV-1 and Neospora caninum – were included in the final analysis. Fetal loss was reported as occurring often in 12 of 49 goat herds (24.5%). The relationship between the hypothesized risk factors and the occurrence of fetal loss was verified in the multivariate logistic regression (α=0.05). Final analysis yielded four risk factors: regular veterinary supervision at least twice a year (OR 0.188; CI 95% 0.054 – 0.656), frequent occurrence of injuries and fractures (OR 3.172; CI 95% 1.081 – 9.310), frequent occurrence of respiratory signs in adult goats (OR 4.848; CI 95% 1.353 – 17.377) and presence of antibodies to C. abortus in a herd (OR 58.116; CI 95% 1.369 – 2466.438). The accuracy of the multivariate model was analyzed using receiver operating characteristic (ROC) curve technique. Area under the curve was 0.895 (CI 95% 0.801-0.981). For optimal cut-off value of 0.20-0.35 the multivariate model had sensitivity of 75.00% and specificity of 89.19% in predicting fetal loss in a herd.
The paper presents the results of studies concerning the Young‘s modulus, critical stress, Poisson‘s ratio and thickness determined for the skin of greenhouse tomato cultivars (Admiro and Encore), and soilgrown varieties (Polset and Surya) comparison. Multivariate analysis of variance and one-dimensional tests [Hinkelmann 2008] were carried out. With the contrasts application the greenhouse varieties were compared with soil-grown ones. The comparison inside both: the greenhouse and soil-grown groups were also conducted. The homogeneity groups containing the average values of defined mechanical parameters of the tomato skin were determined.
The tetraploid (2n = 32) Aconitum sect. Aconitum in the Eastern Carpathians, Southern Carpathians and Apušeni Mts. is represented by high-mountain A. bucovinese, A. firmum subsp. fissurae and their putative taxonomic hybrid A. ×nanum. The aim of the paper was to reveal which delimiting system: taxonomic vs.geographic-population better explains genetic variability (ISSR — Inter Simple Sequence Repeats) of the Aconitum individuals in the Eastern/Southern Carpathians. Twenty nine plants sampled in five populations within entire range of taxa distribution were assigned to genetic groups according to a Bayesian STRUCTURE analysis, neighbour-net classification (NN), and nonmetric multidimensional scaling ordination (NMDS). Three taxa were distributed in four (NN, NMDS) or two (STRUCTURE) genetic groups, and the partitioning of genetic variation with analysis of molecular variance (AMOVA) revealed the highest percentage of variation attributed to the four ISSR genetic groups (22.6%), then to the two STRUCTURE groups (18.9%) and three taxa (15.6%, all P < 0.001), and finally to the three geographic regions (6.5%, P = 0.013). Genetic groups harbored specimens from distant regions: A. f. subsp. fissurae had similar genetic profiles in the Southern Carpathians and Apušeni Mts. (100% support), and some specimens of A. bucovinense had genetic links with A. f. subsp. fissurae. The hybrid species A. ×nanum was genetically specific. We concluded that (i) genetic links between nowadays distantly located populations could have originated in the effect of ancient contacts and hybridization, (ii) probably in the Carpathians two ancient genetic centers of the A. sect. Aconitum existed and (iii) high genetic specificity of the hybrid species A. ×nanum deserves further studies.
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