Morphological Interpretation (morphological + interpretation)

Distribution by Scientific Domains


Selected Abstracts


Testing paleolimnological predictions with molecular data: the origins of Holarctic Eubosmina

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2003
R. A. Haney
Abstract Zooplankton of the family Bosminidae have a unique paleolimnological record in many Holarctic lakes that provides a near continuous record of morphological change for thousands of years. If this morphological change could be interpreted reliably, then a rarely achieved direct observation of macroevolution would be feasible. We tested paleolimnological predictions derived from morphological variation found in the genus Eubosmina using mtDNA and nuclear DNA sequence variation from geographically distant Holarctic sites. The mtDNA and nDNA trees were congruent but genetic divergence was inversely associated with morphological divergence. The three most genetically divergent groups belonged to Eubosmina longispina, whose phylogeography and genetic divergence was consistent with glacial vicariance. The genetic evidence also supported the hypothesis that at least two Nearctic species were recent European introductions. Finally, the genetic evidence was consistent with paleolimnology in the finding of several proposed species undergoing rapid morphological evolution and being post-glacially derived from European E. longispina. The results suggested that lacustrine bosminids are susceptible to geographic speciation processes, and that morphological interpretation of diversity in paleolimnology can be markedly improved by genetic studies. [source]


Histopathological characterization of primary cutaneous melanoma using infrared microimaging: a proof-of-concept study

BRITISH JOURNAL OF DERMATOLOGY, Issue 6 2010
E. Ly
Summary Background, The diagnosis of malignant melanoma is based upon the histological evaluation of the lesion. As such, the morphological interpretation relies on the expertise of a dermatopathologist. Infrared microimaging is emerging as a new powerful tool to investigate tissue biochemistry. Infrared spectra probe the biochemical constitution of the sample and are real tissue-specific spectroscopic fingerprints. Objectives, To assess the potential of infrared microimaging to aid in the analysis of tissue sections from primary cutaneous melanomas. Methods, Ten samples of melanoma sections from the main histological subtypes were investigated using infrared microimaging combined with multivariate statistical analyses. Results, This methodology yielded highly contrasted colour-coded images that permitted to highlight tissue architecture without any staining. It was possible to discriminate tumour areas from normal epidermis automatically, and intratumoral heterogeneity as revealed by our approach was correlated with the aggressiveness of the tumour. Conclusions, This proof-of-concept study shows that infrared microimaging could help in the diagnosis of primary cutaneous melanoma. [source]


Significance of Vectorcardiogram in the Cardiological Diagnosis of the 21st Century

CLINICAL CARDIOLOGY, Issue 7 2007
Andrés Ricardo Pérez Riera M.D
Abstract Until the mid-1980s, it was believed that the vectorcardiogram presented a greater specificity, sensitivity and accuracy in comparison to the conventional electrocardiogram, in the diagnosis of the different heart diseases. Recent studies revealed that the vectorcardiogram still is superior to the electrocardiogram in very specific situations, such as in the evaluation of electrically inactive areas, in intraventricular conduction disorders combined and/or in association to inactive areas, in the identification and location of ventricular preexcitation, in the differential diagnosis of patterns varying from normal of electrical axis deviation, in the evaluation of particular aspects of Brugada syndrome, and in the estimation of the severity of some enlargements, among others. With the advent of computerized vectorcardiography, a technology that improves the processing and recording method; a future still promising is expected for this methodology. In the fields of education and research, vectorcardiography provided a better and more rational insight into the electrical phenomena that occurs spatially, and represented an important impact on the progress of electrocardiography. Although a few medical centers still use the method as a routine, we hope that the use of this resource will not get lost over time, since vectorcardiography still represents a source to enrich science by enabling a better morphological interpretation of the electrical phenomena of the heart. Copyright © 2007 Wiley Periodicals, Inc. [source]


Phylogeny of extant nephilid orb-weaving spiders (Araneae, Nephilidae): testing morphological and ethological homologies

CLADISTICS, Issue 2 2008
Kuntner, Matja
The Pantropical spider clade Nephilidae is famous for its extreme sexual size dimorphism, for constructing the largest orb-webs known, and for unusual sexual behaviors, which include emasculation and extreme polygamy. We synthesize the available data for the genera Nephila, Nephilengys, Herennia and Clitaetra to produce the first species level phylogeny of the family. We score 231 characters (197 morphological, 34 behavioral) for 61 taxa: 32 of the 37 known nephilid species plus two Phonognatha and one Deliochus species, 10 tetragnathid outgroups, nine araneids, and one genus each of Nesticidae, Theridiidae, Theridiosomatidae, Linyphiidae, Pimoidae, Uloboridae and Deinopidae. Four most parsimonious trees resulted, among which successive weighting preferred one ingroup topology. Neither an analysis of an alternative data set based on different morphological interpretations, nor separate analyses of morphology and behavior are superior to the total evidence analysis, which we therefore propose as the working hypothesis of nephilid relationships, and the basis for classification. Ingroup generic relationships are (Clitaetra (Herennia (Nephila, Nephilengys))). Deliochus and Phonognatha group with Araneidae rather than Nephilidae. Nephilidae is sister to all other araneoids (contra most recent literature). Ethological data, although difficult to obtain and thus frequently missing for rare taxa, are phylogenetically informative. We explore the evolution of selected morphological and behavioral characters, discuss and redefine the homology of palpal sclerites, disprove semientelegyny in spiders, trace the newly interpreted evolution of the orb web, and show that nephilid genital morphologies coevolve with sexual behaviors and extreme sexual size dimorphism. Phylogenetic interpretations of behavior suggest new insights into spider biology and avenues for future research. © The Willi Hennig Society 2007. [source]