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Geometric morphometry

Willian T Peçanha, Sergio L Althoff, Daniel Galiano, Fernando M Quintela, Renan Maestri, Gislene L Gonçalves, Thales R O Freitas
Pleistocene climatic oscillations favoured the expansion of grassland ecosystems and open vegetation landscapes throughout the Neotropics, and influenced the evolutionary history of species adapted to such environments. In this study, we sampled populations of the rodent Oxymycterus nasutus endemic to open areas in the Pampas and Atlantic Forest biomes to assess the tempo and mode of population divergence using an integrative approach, including coalescence theory, ecological niche models, and morphometry. Our results indicated that these O...
2017: PloS One
Artemis Synn, Annu Mothakunnel, Fiona Kumfor, Yu Chen, Olivier Piguet, John R Hodges, Muireann Irish
Impaired capacity for Theory of Mind (ToM) represents one of the hallmark features of the behavioral variant of frontotemporal dementia (bvFTD) and is suggested to underpin an array of socioemotional disturbances characteristic of this disorder. In contrast, while social processing typically remains intact in Alzheimer's disease (AD), the cognitive loading of socioemotional tasks may adversely impact mentalizing performance in AD. Here, we employed the Frith-Happé animations as a dynamic on-line assessment of mentalizing capacity with reduced incidental task demands in 18 bvFTD, 18 AD, and 25 age-matched Controls...
November 20, 2017: Journal of Alzheimer's Disease: JAD
Ida Eržen, Jiří Janáček, Marko Kreft, Lucie Kubínová, Erika Cvetko
Capillary network characteristics are invaluable for diagnostics of muscle diseases. Biopsy material is limited in size and mostly not accessible for intensive research. Therefore, especially in human tissue, studies are performed on autopsy material. To approach the problem whether it is reliable to deduce hypotheses from autopsy material to explain physiological and pathological processes, we studied capillarity in pig soleus muscle 1 and 24 hr after death. Capillaries and muscle fibers were immunofluorescently marked, and images were acquired with a confocal microscope...
November 1, 2017: Journal of Histochemistry and Cytochemistry: Official Journal of the Histochemistry Society
Sandra Echtermeyer, Philine H Metelmann, Alexander Hemprich, Karl-Heinz Dannhauer, Karl-Friedrich Krey
OBJECTIVES: This study aims to describe morphological peculiarities of maxillary and mandibular first molars in Europeans, Asians and Europeans with cleft lip and palate. MATERIAL AND METHODS: Reflex microscopy was used to obtain three-dimensional morphometric landmarks from 40 models (11 Europeans and 13 Asians without cleft lip and palate, 16 Europeans with unilateral cleft lip and palate). The cases were examined using traditional morphometry and geometric morphometry, and visualized using thin-plate splines...
2017: PloS One
Julieta Nattero, Romina Valeria Piccinali, Catarina Macedo Lopes, María Laura Hernández, Luciana Abrahan, Patricia Alejandra Lobbia, Claudia Susana Rodríguez, Ana Laura Carbajal de la Fuente
BACKGROUND: The Sordida subcomplex (Triatominae) comprises four species, Triatoma garciabesi, T. guasayana, T. patagonica and T. sordida, which differ in epidemiological importance and adaptations to human environments. Some morphological similarities among species make taxonomic identification, population differentiation and species delimitation controversial. Triatoma garciabesi and T. sordida are the most similar species, having been considered alternatively two and a single species until T...
September 6, 2017: Parasites & Vectors
Stefan Curth, Martin S Fischer, Kornelius Kupczik
The temporomandibular joint (TMJ) conducts and restrains masticatory movements between the mammalian cranium and the mandible. Through this functional integration, TMJ morphology in wild mammals is strongly correlated with diet, resulting in a wide range of TMJ variations. However, in artificially selected and closely related domestic dogs, dietary specialisations between breeds can be ruled out as a diversifying factor although they display an enormous variation in TMJ morphology. This raises the question of the origin of this variation...
September 1, 2017: Annals of Anatomy, Anatomischer Anzeiger: Official Organ of the Anatomische Gesellschaft
Adriana Olenici, Saúl Blanco, María Borrego-Ramos, Laura Momeu, Călin Baciu
Metal pollution of aquatic habitats is a major and persistent environmental problem. Acid mine drainage (AMD) affects lotic systems in numerous and interactive ways. In the present work, a mining area (Roșia Montană) was chosen as study site, and we focused on two aims: (i) to find the set of environmental predictors leading to the appearance of the abnormal diatom individuals in the study area and (ii) to assess the relationship between the degree of valve outline deformation and AMD-derived pollution. In this context, morphological differences between populations of Achnanthidium minutissimum and A...
July 11, 2017: Ecotoxicology
Corentin Bochaton, Salvador Bailon, Anthony Herrel, Sandrine Grouard, Ivan Ineich, Anne Tresset, Raphaël Cornette
Fossil remains provide useful insights into the long-term impact of anthropogenic phenomena on faunas and are often used to reveal the local (extirpations) or global (extinctions) losses of populations or species. However, other phenomena such as minor morphological changes can remain inconspicuous in the fossil record depending on the methodology used. In this study, we used the anole of Marie-Galante Island (Anolis ferreus) in Guadeloupe (French, West Indies) as a model to demonstrate how the morphological evolution of an insular lizard can be tracked through the Pleistocene/Holocene climatic transition and the recent anthropization of the island...
June 28, 2017: Proceedings. Biological Sciences
Diego Gallo, Orestis Vardoulis, Pierre Monney, Davide Piccini, Panagiotis Antiochos, Juerg Schwitter, Nikolaos Stergiopulos, Umberto Morbiducci
In this study, an image-based morphometry toolset quantifying geometric descriptors of the left ventricle, aorta and their coupling is applied to investigate whether morphological information can differentiate between subjects affected by diastolic dysfunction (patient group) and their age-matched controls (control group). The ventriculo-aortic region of 20 total participants (10 per group) were segmented from high-resolution 3D magnetic resonance images, from the left ventricle to the descending aorta. Each geometry was divided into segments in correspondence of anatomical landmarks...
June 21, 2017: Medical Engineering & Physics
Bruna Demari-Silva, Laura Cristina Multini, Lincoln Suesdek, Tatiane M P Oliveira, Maria Anice Mureb Sallum, Mauro Toledo Marrelli
Culex coronator Dyar and Knab and Culex usquatus Dyar belong to the Coronator Group of the subgenus Culex. Culex coronator and Cx. usquatus are widespread and sympatric throughout their distribution range, which includes Brazil. Morphological identification of these species is based primarily on the characteristics of the male genitalia; females are indistinguishable using the qualitative characteristics employed in identification keys. The primary objective of this study was to distinguish females of Cx. coronator from those of Cx...
July 1, 2017: Journal of Medical Entomology
Jie Zhang, Jie Shi, Cynthia Stonnington, Qingyang Li, Boris A Gutman, Kewei Chen, Eric M Reiman, Richard J Caselli, Paul M Thompson, Jieping Ye, Yalin Wang
Mild Cognitive Impairment (MCI) is a transitional stage between normal age-related cognitive decline and Alzheimer's disease (AD). Here we introduce a hyperbolic space sparse coding method to predict impending decline of MCI patients to dementia using surface measures of ventricular enlargement. First, we compute diffeomorphic mappings between ventricular surfaces using a canonical hyperbolic parameter space with consistent boundary conditions and surface tensor-based morphometry is computed to measure local surface deformations...
October 2016: Medical Image Computing and Computer-assisted Intervention: MICCAI ..
Dimitrios P Sokolis, Despoina C Petsepe, Stavroula A Papadodima, Stavros K Kourkoulis
The ureter has been largely overlooked heretofore in the study of the biomechanics of soft biological tissues, although there has been significant motivation to use its biomechanical properties as inputs to mathematical models of ureteral function. Herein, we used histological analysis for quantification of collagen contents and thickness/area of ureteral layers, with concomitant geometrical analysis of zero-stress and no-load states, and inflation/extension testing to biomechanically characterize with the Fung-type model the ureters from cadavers...
January 25, 2017: Journal of Biomechanics
Jennifer A McKenzie, Evan Buettmann, Adam C Abraham, Michael J Gardner, Matthew J Silva, Megan L Killian
Scleraxis (Scx) is a known regulator of tendon development, and recent work has identified the role of Scx in bone modeling. However, the role of Scx in fracture healing has not yet been explored. This study was conducted to identify the role of Scx in cortical bone development and fracture healing. Scx green fluorescent protein-labeled (ScxGFP) reporter and Scx-knockout (Scx-mutant) mice were used to assess bone morphometry and the effects of fracture healing on Scx localization and gene expression, as well as callus healing response...
March 2017: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Javier Irurita Olivares, Inmaculada Alemán Aguilera
In the context of physical and forensic anthropology, when a child's skeleton is damaged or in poor condition, which is common, many of the metric methods for the estimation of skeletal age cannot be used. In these circumstances, those more resistant bones, such as the pars basilaris, will be most useful. The aims of this study were to test existing methods for estimating skeletal age from the metric study of the pars basilaris and to propose new regression formulae. One hundred fourteen individuals aged between 5 months of gestation and 6 years were analyzed; seven measures were taken from each pars basilaris using a digital caliper...
May 2017: International Journal of Legal Medicine
M Dadáková, V Cagáňová, J Dupej, E Hoffmannová, J Borský, J Velemínská
PURPOSE: To evaluate the facial morphology of pre-school patients with various types of orofacial cleft after neonatal cheiloplasty in pre-school aged children; and to compare facial variability and mean shape with age-corresponding healthy controls. MATERIALS AND METHODS: The sample included 40 patients with unilateral cleft lip (CL), 22 patients with unilateral cleft lip and palate (UCLP), and 10 patients with bilateral cleft lip and palate (BCLP). Patients were divided into two age categories, with a mean age of 3 years and 4...
September 2016: Journal of Cranio-maxillo-facial Surgery
Ljiljana Šašić, Jelena Ačanski, Ante Vujić, Gunilla Ståhls, Snežana Radenković, Dubravka Milić, Dragana Obreht Vidaković, Mihajla Đan
The Merodon aureus species group (Diptera: Syrphidae: Eristalinae) comprises a number of different sub-groups and species complexes. In this study we focus on resolving the taxonomic status of the entity previously identified as M. cinereus B, here identified as M. atratus species complex. We used an integrative approach based on morphological descriptions, combined with supporting characters that were obtained from molecular analyses of the mitochondrial cytochrome c oxidase I gene as well as from geometric morphometry of wing and surstylus shapes and environmental niche comparisons...
2016: PloS One
Junbin Huang, He Liu, Defeng Wang, James F Griffith, Lin Shi
OBJECTIVE: The purpose of our study is to give a relatively objective definition of talar dome and its shape approximations to sphere (SPH), cylinder (CLD) and bi-truncated cone (BTC). MATERIALS AND METHODS: The "talar dome" is well-defined with the improved Dijkstra's algorithm, considering the Euclidean distance and surface curvature. The geometric similarity between talar dome and ideal shapes, namely SPH, CLD and BTC, is quantified. 50 unilateral CT datasets from 50 subjects with no pathological morphometry of tali were included in the experiments and statistical analyses were carried out based on the approximation error...
April 2017: Computerized Medical Imaging and Graphics: the Official Journal of the Computerized Medical Imaging Society
Beatriz Gamarra, Mónica Nova Delgado, Alejandro Romero, Jordi Galbany, Alejandro Pérez-Pérez
Morphology has been widely used for inferring the phylogenies of numerous taxonomic groups. Recent molecular studies performed on extant non-human primates, however, have cast doubt on the reliability of cranial and postcranial characters for characterizing evolutionary affinities. Because molecular evidence is often not available for fossil specimens, detecting phylogenetic signals in anatomical features is of great relevance. Here we have analyzed molar (M1 and M2) crown shape by means of geometric morphometrics in a large sample of both extant and fossil Miocene catarrhine primates to detect the phylogenetic signal in molar morphometry...
May 2016: Journal of Human Evolution
C A Bulant, P J Blanco, T P Lima, A N Assunção, G Liberato, J R Parga, L F R Ávila, A C Pereira, R A Feijóo, P A Lemos
This work presents a computational framework to perform a systematic and comprehensive assessment of the morphometry of coronary arteries from in vivo medical images. The methodology embraces image segmentation, arterial vessel representation, characterization and comparison, data storage, and finally analysis. Validation is performed using a sample of 48 patients. Data mining of morphometric information of several coronary arteries is presented. Results agree to medical reports in terms of basic geometric and anatomical variables...
May 11, 2016: International Journal for Numerical Methods in Biomedical Engineering
Jaeil Kim, Maria del C Valdés Hernández, Natalie A Royle, Susana Muñoz Maniega, Benjamin S Aribisala, Alan J Gow, Mark E Bastin, Ian J Deary, Joanna M Wardlaw, Jinah Park
BACKGROUND: Structural changes of the brain's third ventricle have been acknowledged as an indicative measure of the brain atrophy progression in neurodegenerative and endocrinal diseases. To investigate the ventricular enlargement in relation to the atrophy of the surrounding structures, shape analysis is a promising approach. However, there are hurdles in modeling the third ventricle shape. First, it has topological variations across individuals due to the inter-thalamic adhesion. In addition, as an interhemispheric structure, it needs to be aligned to the midsagittal plane to assess its asymmetric and regional deformation...
June 2016: Computer Methods and Programs in Biomedicine
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