Search results for "Morphological analysis"
showing 10 items of 21 documents
Cryptic species unveiled: the case of the nematode Spauligodon atlanticus
2013
The implementation of molecular tools in parasitology has led to the discovery of numerous cryptic species. However, detailed morphological studies are needed to evaluate the cryptic nature of such species, as well as to provide an appropriate and formal description. Recent phylogenetic analyses using mitochondrial and nuclear genes have revealed that the nematode Spauligodon atlanticus, parasite of lizards of the genus Gallotia endemic to the Canary Islands, consists of two highly divergent and unrelated lineages, one in the eastern islands and the other in the western ones. This study provides a detailed morphological analysis of the two S. atlanticus lineages characterized genetically, b…
Variation in the Senecio aethnensis group (Asteraceae) along an altitudinal gradient
2003
ABSTRACT The variability of the Senecio aethnensis group was investigated through morphometric analyses of seven populations along an altitudinal transect on Mt. Etna (E Sicily). The data obtained show a separation into two groups, one including the populations of the upper and middle belts, at and above 1700 m, the other including the populations from lower altitudes. In the first group a clinal morphological variation in several reproductive and vegetative characters was observed in relation to altitude. The analysis of leaf characters in progeny cultivated under uniform conditions confirmed the differentiation into the two groups, which are to be treated as separate species, i.e. S. aeth…
Baltu filoloģija, 23. sēj., Nr.2
2015
Morphological Analysis Combined with a Machine Learning Approach to Detect Utrasound Median Sagittal Sections for the Nuchal Translucency Measurement
2017
The screening of chromosomal defects, as trisomy 13, 18 and 21, can be obtained by the measurement of the nuchal translucency thickness scanning during the end of the first trimester of pregnancy. This contribution proposes an automatic methodology to detect mid-sagittal sections to identify the correct measurement of nuchal translucency. Wavelet analysis and neural network classifiers are the main strategies of the proposed methodology to detect the frontal components of the skull and the choroid plexus with the support of radial symmetry analysis. Real clinical ultrasound images were adopted to measure the performance and the robustness of the methodology, thus it can be highlighted an er…
Hybridization in Capparis spinosa L.: Molecular and morphological evidence from a Mediterranean island complex
2014
Inter-Simple Sequence Repeat (ISSR) molecular markers and morphological analysis were used in order to characterize wild populations and cultivated forms of orphan crop species Capparis spinosa L. in a Mediterranean island complex. Nineteen wild populations belonging to two different subspecies, C. spinosa subsp. spinosa and subsp. rupestris, were sampled in different environments in Sicily and the surrounding islets Lampedusa, Pantelleria and Salina. Different biotypes cultivated in Pantelleria and Salina were analyzed. Six ISSR primers were selected for genetic characterization, and all clear and reproducible bands were scored and analyzed. Among the 47 ISSR bands obtained, 97.5% were pol…
A taxonomic revision of westernEupholidopterabush crickets (Orthoptera: Tettigoniidae): testing the discrimination power of DNA barcode
2013
The genus Eupholidoptera includes 46 Mediterranean species distributed from Turkey to Greece, Italy and southern France. In the eastern part of its range, Eupholidoptera has been considered to consist of several distinct species, while in the Balkans and Italian peninsula only E. chabrieri has been recognized. However, the status of some Italian populations, confined to particular geographic areas, remains uncertain. To investigate the delimitation of the Italian taxa of Eupholidoptera, we performed both morphological and molecular analyses. Morphological analysis was carried out by considering diagnostic characters usually used to distinguish different taxa, such as the shape of titillator…
The importance of integrative approaches in nematode taxonomy: the validity of Parapharyngodon and Thelandros as distinct genera
2018
AbstractDespite the advances of molecular tools, new nematode species are still described mainly based on morphological characters. Parapharyngodon and Thelandros are two genera of oxyurids with unclear related taxonomic histories. Here we use morphological characters (linear measurements and categorical variables) and genetic information (18S rRNA, 28S rRNA and COI partial gene sequences) to confirm the relationships between representatives of these two genera and to determine whether they can be discriminated morphologically. Genetic results confirm the existence of two main clades, mostly congruent with Parapharyngodon and Thelandros genera but with several discordances. Thelandros is po…
Tetraphyllidean plerocercoids from Western Mediterranean cetaceans and other marine mammals around the world: a comprehensive morphological analysis.
2005
Tetraphyllidean plerocercoids have occasionally been reported in marine mammals, but they have rarely been described in detail, and the ecological significance of these infections is unclear. We described plerocercoids collected from the mucosa of the terminal colon and rectum, the anal crypts, and the hepatopancreatic ducts of 7 striped dolphins Stenella coeruleoalba, 1 Cuvier's beaked whale Ziphius cavirostris, and 3 Risso's dolphins Grampus griseus from the Spanish Mediterranean. We also examined undescribed plerocercoids from 3 cetacean species from the Atlantic and the Pacific. All plerocercoids had a lanceolate body, and a scolex with an apical sucker and 4 sessile monolocular bothrid…
Morphological analysis of the skeletal development in lateral cephalometric radiographs of HIV infected children ongoing Highly Active Antiretroviral…
2018
Background To investigate the skeletal development of HIV infected children through a morphological analysis of the cervical vertebrae (CV) in lateral cephalometric radiographs. Material and Methods The sample consisted of 86 lateral cephalometric radiographs of male and female children aged between 6 and 14 years old. The radiographs were equally distributed in groups 1 (HIV infected children) and 2 (non-infected children, paired by sex and age). Two examiners analyzed the CV according to the method of Hassel and Farman (1995). Spearman correlation coefficient was used to associate age and skeletal development within groups, while Mann-Whitney test compared the skeletal development between…
Young’s modulus and indirect morphological analysis of Bi2Se3nanoribbons by resonance measurements
2017
An electrostatically induced resonance behaviour of individual topological insulator Bi2Se3 nanoribbons grown by a catalyst free vapour-solid synthesis was studied in situ by scanning electron microscopy. It was demonstrated that the relation between the resonant frequencies of vibrations in orthogonal planes can be applied to distinguish the nanoribbons with rectangular cross-sections from the nanoribbons having step-like morphology (terraces). The average Young's modulus of the Bi2Se3 nanoribbons with rectangular cross-sections was found to be 44 ± 4 GPa.