The traditional method of analysing cephalograms--conventional cephalometric analysis (CCA)--involves the calculation of linear distance measurements, angular measurements, area measurements, and ratios. Because shape information cannot be determined from these 'size-based' measurements, an increasing number of studies employ geometric morphometric tools in the cephalometric analysis of craniof...

The history of cotton (Gossypium sp), which has become along past millennia a plant major economic interest, relies on the dried or charred seeds found in archaeobotanical assemblages. Our capacity to document dispersal routes cotton, however, is hampered by lack taxonomic resolution at specific levels based current seed anatomic features. In order explore signal interspecific level seeds, and ...

—Although morphological variation is known to influence the evolutionary fates of species, the relationship between morphological variation and survivorship in the face of extinction-inducing perturbations is poorly understood. Here, we investigate this relationship for veneroid bivalves in association with the Plio-Pleistocene extinction in Florida. Fourteen pairs of related species were selec...

In this paper we consider a Procrustes problem on the set of sub-Stiefel matrices. A sub-Stiefel matrix is a matrix that results from deleting simultaneously the last row and the last column of an orthogonal matrix. An iterative algorithm for computing the solution of the sub-Stiefel Procrustes problem is proposed. For these purposes we investigate the properties of sub-Stiefel matrices. We als...

Objective To assess the ANB angle's and Wits appraisal's diagnostic performance using an extended version of Receiver Operating Curve (ROC) analysis, which renders ROC surfaces. These were calculated for both the conventional and normalized cephalometric tests (calculated by exchanging the patient's reference landmarks with those of the Procrustes superimposed sample mean shape).The required 'g...

The Procrustes distance is used to quantify the similarity or dissimilarity of (3-dimensional) shapes, and extensively used in biological morphometrics. Typically each (normalized) shape is represented by N landmark points, chosen to be homologous (i.e. corresponding to each other), as much as possible, and the Procrustes distance is then computed as infR ∑N j=1 ‖Rxj − xj‖, where the minimizati...

The ecological niche models can be important for biogeographic patterns and processes geometric morphometrics involves identifying changes that have occurred comparing them to other specimens from different places and/or environmental conditions, assessing whether the environment is influencing such change. present work aimed verify potential model of distribution Apis mellifera analyze if ther...

the body shape of fishes is influenced by environmental parameters and the habitat condition. the present study investigated morphological characteristics phenotypic plasticity of barbus lacerata in the zarrineh river and the role of environmentalfactors influencing the phenotypic plasticity. three hundred specimens were caught using electric fishing, anaesthetized with clove powder, fixed in 1...

There has been substantial interest in the development of methods for processing diffusion tensor fields, taking into account the non-Euclidean nature of the tensor space. In this paper, we generalise Procrustes analysis to weighted Procrustes analysis for diffusion tensor smoothing, interpolation, regularisation and segmentation in which an arbitrary number of tensors can be processed efficien...