Search results for "Clad"
showing 10 items of 495 documents
Molecular and Morphological Differentiation of Two Similar Species of Accacoeliidae (Digenea):Accacladocoelium macrocotyleandA. nigroflavumfrom Sunfi…
2014
In a study of 106 sunfish, Mola mola (L.), from Mediterranean waters, 2,731 worms, belonging to 2 congeneric species of accacoeliids, Accacladocoelium macrocotyle (Diesing, 1858) Robinson, 1934 and Accacladocoelium nigroflavum (Rudolphi, 1819) Robinson, 1934 , were collected from the digestive system. It is often difficult to differentiate between these 2 species as they are sympatric and very similar; in fact, according to previous descriptions, the extent of the vitellarium is the only interspecific difference, described as extending posteriorly to the ovary in A. macrocotyle and as anterior to the anterior testis in A. nigroflavum. However, this diagnostic trait is not always valid; more…
Interrelationships of the Haploporinae (Digenea: Haploporidae): A molecular test of the taxonomic framework based on morphology
2009
The taxonomic framework of the Haploporidae is evaluated and the relationships within the Haploporinae are assessed for the first time at the generic level using molecular data. Partial 28S and complete ITS2 rDNA sequences from representatives of six of the nine recognised genera within the Haploporinae were analysed together with published sequences representing members of two haploporid subfamilies and of the closely related family Atractotrematidae. Molecular analyses revealed: (i) a close relationship between the Atractotrematidae and the Haploporidae; (ii) strong support for the monophyly of the Haploporinae, Dicrogaster and Saccocoelium, and the position of Ragaia within the Haplopori…
UV-B-Induced acute toxicity of pyrene to the waterflea Daphnia magna in natural freshwaters.
1999
Abstract The effects of various water characteristics in natural freshwaters on the acute toxicity of one polycyclic aromatic hydrocarbon (PAH), pyrene, to a pelagic invertebrate Daphnia magna was studied under ultraviolet B (UV-B) radiation and in the dark. Pyrene was photoactivated and was more toxic to D. magna in the presence of UV-B radiation. Dissolved organic material (DOM), measured as dissolved organic carbon (DOC), significantly reduced the photoenhanced toxicity of pyrene. Under UV-B radiation the EC50 values were lower and in relation to the amount of DOM, ranging from 3.0 to 30.0 μg/L pyrene, whereas in the dark they were between 29.2 and 54.8 μg/L and not related to the amount…
Evolutionary site-number changes of ribosomal DNA loci during speciation: complex scenarios of ancestral and more recent polyploid events.
2015
Genes encoding ribosomal RNA are universal key constituents of eukaryotic genomes, but the number of loci varies between species. We assessed the evolutionary trends in site-number changes of rDNA loci during speciation in a lineage of the cabbage family, characterized by complex scenarios of polyploidy. Our results suggest the existence of constrictions to burst loci amplification in the 5S rDNA family in polyploids and an overall trend to further reduce their number. The 45S rDNA site change in polyploids tells a different story, implying loci amplification in most of the polyploid entities.
Organophosphonate utilization by the wild‐type strain of cladosporium resinae
1997
We studied the biodegradation of compounds containing phosphorus‐to‐carbon bond by using wild‐type strain of Cladosporium resinae. The substrate specificity of the strain was studied and we found that it is able to utilize a range of structurally diverse organophosphonates as a sole source of phosphorus. This ability is inducible as indicated by the presence of a lag phase of the growth. A popular herbicide glyphosate is also degraded by the fungi. This indicates that Cladosporium resinae may play an important role in biodegradation of this herbicide. The strain which we used, however, did not metabolise any phosphonates when they served as the sole carbon or nitrogen sources.
Arthrinium phaeospermum , Phoma cladoniicola and Ulocladium consortiale , New Olive Pathogens in Italy
2013
In recent years, leaf necrosis and twig dieback in the olive crop have been detected in Sicily (Italy). In this article, we identify the predominant fungal species associated with symptomatic leaves and twigs, using morphological features and DNA sequencing of the internal transcribed spacer (ITS) region, as Alternaria alternata, Arthrinium phaeospermum, Phoma cladoniicola and Ulocladium consortiale. The pathogenicity of these four species was tested on olive plants cv. Biancolilla. All species were pathogenic on leaves, but only U. consortiale produced cortical lesions on twigs, thus suggesting its main role in the Olea europaea twig dieback. To our knowledge, this is the first report of A…
The phylogeny and biogeography of Gentiana L. sect. Ciminalis (Adans.) Dumort.: A historical interpretation of distribution ranges in the European hi…
1998
Abstract Gentiana sect. Ciminalis consists of seven mostly ecologically or geographically vicariant and closely related species which are distributed throughout the South and Central European high mountains. The analysis of a RAPD data set and trn L-intron and ITS sequences resulted in slightly different phylogenetic hypotheses. In the preferred hypothesis the group consists of two completely resolved main lineages: 1) G. clusii and G. alpina. 2) G. dinarica, G. acaulis, G. ligustica, G. angustifolia and G. occidentalis. The most important conclusions we have drawn from this phylogenetic hypothesis and from the observed patterns of molecular variation are: 1) The calcifuge ecology of G. aca…
Size distribution of Daphnia longispina in the vertical profile
1997
D. longispina of the meromictic lake El Tobar is a round-headed form. It never has a helmet, but in summer a small proportion of immature individuals (0.9–1.2 mm females and males) have one or two neck teeth. The size structure of this Daphnia population, as well as the vertical distribution and migration of different size-classes, were studied in September and November of 1991 and April of 1992. The large variation in mean size and size at first reproduction, as well as the occurrence of different patterns of vertical migration are interpreted as responses to different predator situations. At the end of April, when Daphnia mortality by visually hunting predators is dominating, a typical no…
Italian Peninsula preserves an evolutionary lineage of the fat dormouse Glis glis L. (Rodentia: Gliridae)
2010
The present study examines the population genetic structure of fifty-nine specimens of Glis glis (Linneaus, 1766) from thirteen localities in central Europe, sequencing a 400-bp segment of the mitochondrial cytochrome b (cyt b) gene and a 673-bp segment of the cytochrome c oxidase subunit I (COI) gene. The consensus tree obtained from Bayesian analysis revealed a robust dichotomy, showing two sister groups: one clade includes samples from a wide geographical area, extending from north-central Europe to northern Italy (major branch sensu Bilton), and the other comprises samples collected in central and southern Italy and in Sicily (Italian branch). According to the Tajima–Nei model, the two …
Estudio in vitro de la resistencia a la fractura tras la fatiga de coronas cementadas sobre pilares de circona
2015
El reemplazo de un diente perdido en el sector anterior mediante implantes es, a día de hoy, una alternativa válida al tratamiento convencional mediante prótesis fija. Uno de los requisitos para lograr una estética óptima en el sector anterior con implantes es el de conseguir una restauración con un perfil de emergencia de apariencia natural, que armonice con los dientes naturales adyacentes y con los tejidos blandos periimplantarios. Si utilizamos un pilar metálico, podría producirse un halo grisáceo alrededor de los tejidos periimplantarios, especialmente en los pacientes con un biotipo fino. Si utilizamos un pilar cerámico junto con una corona cerámica lograríamos un mejor resultado esté…