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Geometric morphometry

Emily L Marshall, David Borrego, James C Fudge, Dhanashree Rajderkar, Wesley E Bolch
PURPOSE: To assess various computational phantom alignment techniques within Monte Carlo radiation transport models of pediatric fluoroscopically-guided cardiac interventional studies. METHODS: Logfiles, including all procedure radiation and machine data, were extracted from a Toshiba infinix-I unit in the University of Florida Pediatric Catheterization Laboratory for a cohort of 10 patients. Two different alignment methods were then tested against a ground-truth standard based upon identification of a unique anatomic reference point within images co-registered to specific irradiation events within each procedure...
June 13, 2018: Medical Physics
Xu Huang, Donghui Liu, Xiaoping Yin, Yajun E, Zhiqiang Li, Wenchang Tan, Yunlong Huo
Posterior communicating artery (PCoA) aneurysms frequently rupture in small size (<7 mm). The aim of the study is to demonstrate morphometric and hemodynamic analyses in ruptured and unruptured PCoA aneurysms to improve predictive accuracy for rupture. Geometrical models were reconstructed from rotational DSA images of 57 ruptured and 22 unruptured side-wall PCoA aneurysms, which were classified into four two-dimensional (2D) groups by a combination of H/D and H/S ratios (H: dome height, D: dome diameter, and S: semi-axis height)...
May 22, 2018: Journal of Biomechanics
Andrea Nappo, Xabier Rey, Daniel Pellegrini, Giuseppe Bonomolo, Fabio Crocetta
The family Drilliidae includes approximately 30 genera and 500 recent species. Among them, the genus Conopleura includes three recent species and shows a disjunct distribution in the central Indo-Pacific and the temperate northern Atlantic (Mediterranean Sea). Here, we review the genus, redescribe it, and investigate the validity of its accepted taxa by shell morphology and geometric morphometry. Conopleura striata and C. latiaxisa are considered as valid species. Their distribution has been enlarged to Taiwan and India for C...
March 11, 2018: Zootaxa
M Ramón, F Martínez-Pastor
Computer-aided sperm analysis (CASA) produces a wealth of data that is frequently ignored. The use of multiparametric statistical methods can help explore these datasets, unveiling the subpopulation structure of sperm samples. In this review we analyse the significance of the internal heterogeneity of sperm samples and its relevance. We also provide a brief description of the statistical tools used for extracting sperm subpopulations from the datasets, namely unsupervised clustering (with non-hierarchical, hierarchical and two-step methods) and the most advanced supervised methods, based on machine learning...
April 23, 2018: Reproduction, Fertility, and Development
Xiaoping Yin, Xu Huang, Qiao Li, Li Li, Pei Niu, Minglu Cao, Fei Guo, Xuechao Li, Wenchang Tan, Yunlong Huo
Background: The formation of hepatic hemangiomas (HH) is associated with VEGF and IL-7 that alter conduit arteries and small arterioles. To our knowledge, there are no studies to investigate the effects of HH on the hemodynamics in conduit arteries. The aim of the study is to perform morphometric and hemodynamic analysis in abdominal conduit arteries and bifurcations of HH patients and controls. Methods: Based on morphometry reconstructed from CT images, geometrical models were meshed with prismatic elements for the near wall region and tetrahedral and hexahedral elements for the core region...
2018: Frontiers in Physiology
N Macleod, M J R Hall, A H Wardhana
The Old World screwworm fly (OWSF), Chrysomya bezziana (Diptera: Calliphoridae), is an important agent of traumatic myiasis and, as such, a major human and animal health problem. In the implementation of OWSF control operations, it is important to determine the geographical origins of such disease-causing species in order to establish whether they derive from endemic or invading populations. Gross morphological and molecular studies have demonstrated the existence of two distinct lineages of this species, one African and the other Asian...
April 15, 2018: Medical and Veterinary Entomology
Veronika Moslerová, Martina Dadáková, Ján Dupej, Eva Hoffmannova, Jiří Borský, Miloš Černý, Přemysl Bejda, Karolína Kočandrlová, Jana Velemínská
OBJECTIVES: To evaluate facial asymmetry changes in pre-school patients with orofacial clefts after neonatal cheiloplasty and to compare facial asymmetry with age-matched healthy controls. METHODS AND MATERIALS: The sample consisted of patients with unilateral cleft lip (UCL), unilateral cleft lip and palate (UCLP), and bilateral cleft lip and palate (BCLP). The patients were divided in two age groups with a mean age of 3 years (n = 51) and 4.5 years (n = 45), respectively, and 78 age-matched individuals as controls...
May 2018: International Journal of Pediatric Otorhinolaryngology
Marco Musy, Kevin Flaherty, Jelena Raspopovic, Alexandre Robert-Moreno, Joan T Richtsmeier, James Sharpe
To determine the developmental stage of embryonic mice, we apply a geometric morphometric approach to the changing shape of the mouse limb bud as it grows from embryonic day 10 to embryonic day 15 post-conception. As the ontogenetic sequence results in the de novo emergence of shape features not present in the early stages, we have created a standard ontogenetic trajectory for limb bud development - a quantitative characterization of shape change during limb morphogenesis. This trajectory of form as a function of time also gives us the reverse function: the ability to infer developmental stage from form, with a typical uncertainty of 2 h...
April 5, 2018: Development
A G Vasil'ev, V N Bol'shakov, I A Vasil'eva, N G Evdokimov, N V Sineva
Geometric morphometry has been used to reveal transformations of mandible morphogenesis in the offspring of mole voles resettled to the northern part of the species range from a southern population. The transformations were new compared to both the original (southern) and the aboriginal (northern) populations. A significant increase in the intragroup morphological disparity estimated by the mean nearest neighbor distance (MNND) in the resettled animals compared to both aboriginal populations is an indirect indication of an increased developmental instability in the resettled animals exposed to new climatic conditions...
January 2018: Doklady Biological Sciences: Proceedings of the Academy of Sciences of the USSR, Biological Sciences Sections
Ehsan Abadi, William P Segars, Gregory M Sturgeon, Justus E Roos, Carl E Ravin, Ehsan Samei
The purpose of this paper was to extend the extended cardiac-torso (XCAT) series of computational phantoms to include a detailed lung architecture including airways and pulmonary vasculature. Eleven XCAT phantoms of varying anatomy were used in this paper. The lung lobes and initial branches of the airways, pulmonary arteries, and veins were previously defined in each XCAT model. These models were extended from the initial branches of the airways and vessels to the level of terminal branches using an anatomically-based volume-filling branching algorithm...
March 2018: IEEE Transactions on Medical Imaging
Sh T Zhorzholiani, A A Mironov, E A Talygin, Yu M Tsyganokov, A M Agafonov, G I Kiknadze, A Yu Gorodkov, L A Bokeriya
Analysis of the data of morphometry of aortic casts, aortography at different pressures, and multispiral computer tomography of the aorta with contrast and normal pulse pressure showed that geometric configuration of the flow channel of the aorta during the whole cardiac cycle corresponded to the conditions of self-organization of tornado-like quasipotential flow described by exact solutions of the Navier-Stokes equation and continuity of viscous fluid typical for this type of fluid flows. Increasing pressure in the aorta leads to a decrease in the degree of approximation of the channel geometry to the ratio of exact solution and increases the risk of distortions in the structure of the flow...
March 2018: Bulletin of Experimental Biology and Medicine
Miroslav Jiřík, Martin Bartoš, Petr Tomášek, Anna Malečková, Tomáš Kural, Jana Horáková, David Lukáš, Tomáš Suchý, Petra Kochová, Marie Hubálek Kalbáčová, Milena Králíčková, Zbyněk Tonar
Quantification of the structure and composition of biomaterials using micro-CT requires image segmentation due to the low contrast and overlapping radioopacity of biological materials. The amount of bias introduced by segmentation procedures is generally unknown. We aim to develop software that generates three-dimensional models of fibrous and porous structures with known volumes, surfaces, lengths, and object counts in fibrous materials and to provide a software tool that calibrates quantitative micro-CT assessments...
February 24, 2018: Microscopy Research and Technique
Dominik Vondráček, Aneta Fuchsová, Dirk Ahrens, David Král, Petr Šípek
The development of modern methods of species delimitation, unified under the "integrated taxonomy" approach, allows a critical examination and re-evaluation of complex taxonomic groups. The rose chafer Protaetia (Potosia) cuprea is a highly polymorphic species group with a large distribution range. Despite its overall commonness, its taxonomy is unclear and subject to conflicting hypotheses, most of which largely fail to account for its evolutionary history. Based on the sequences of two mitochondrial markers from 65 individuals collected across the species range, and a detailed analysis of morphological characters including a geometric morphometry approach, we infer the evolutionary history and phylogeography of the P...
2018: PloS One
Prashant Kumar Prasad, Pravin Salunke, Daisy Sahni, Parveen Kalra
Purpose: The existing literature on lateral atlantoaxial joints is predominantly on bony facets and is unable to explain various C1-2 motions observed. Geometric morphometry of facets would help us in understanding the role of cartilages in C1-2 biomechanics/kinematics. Objective: Anthropometric measurements (bone and cartilage) of the atlantoaxial joint and to assess the role of cartilages in joint biomechanics. Materials and Methods: The authors studied 10 cadaveric atlantoaxial lateral joints with the articular cartilage in situ and after removing it, using three-dimensional laser scanner...
October 2017: Journal of Craniovertebral Junction and Spine
Watcharapong Hongjamrassilp, Adam P Summers, Philip A Hastings
The Sarcastic Fringehead (Neoclinus blanchardi, Teleostei) exhibits an extreme version of a common aggressive display, the "gaping display," in which an open mouth is presented toward an opponent. Males of this species have extremely long jaws that extend posteriorly well past the posterior margin of the head and are flared laterally during the gaping display. In this study, we explored morphological traits related to this extraordinary display in this and related species of blennies. Morphological modifications include enlargement of the buccopalatal membrane, elongation of the maxilla via an uncalcified posterior extension, and evolution of a novel hinge between the anterior maxilla and lacrimal bones permitting lateral movement of the upper jaw...
May 2018: Journal of Morphology
Manohar Latha, Ganesan Kavitha
OBJECTIVE: Schizophrenia (SZ) is a psychiatric disorder that especially affects individuals during their adolescence. There is a need to study the subanatomical regions of SZ brain on magnetic resonance images (MRI) based on morphometry. In this work, an attempt was made to analyze alterations in structure and texture patterns in images of the SZ brain using the level-set method and Laws texture features. MATERIALS AND METHODS: T1-weighted MRI of the brain from Center of Biomedical Research Excellence (COBRE) database were considered for analysis...
February 3, 2018: Magma
Cláudia F Marinho, Fernando L Cônsol, Angélica Maria Penteado-Dias, Roberto A Zucchi
This study clarifies the identity of two morphs that appear similar but not identical to the braconid wasp Doryctobracon areolatus (Szépligeti), by analyses of fore wing morphometry and the ITS2 and D2 region of 28S ribosomal DNA. Wing measurements of D. areolatus and the two morphs, one with a yellow stigma and one with a brown stigma, from several Brazilian localities, were taken and subjected to geometric morphometry. Evaluation of 20 anatomical points on the fore wing by means of multivariate analysis revealed that these morphs consistently differ from D...
November 24, 2017: Zootaxa
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...
2018: 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...
January 2018: Journal of Histochemistry and Cytochemistry: Official Journal of the Histochemistry Society
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