scholarly journals Geometric morphometric analysis of cyclical body shape changes in color pattern variants of Cichla temensis Humboldt, 1821 (Perciformes: Cichlidae) demonstrates reproductive energy allocation

2015 ◽  
Vol 13 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Paul Reiss ◽  
Thomas M. Grothues
Keyword(s):  
Sexual Maturity ◽  
Shape Change ◽  
Flood Pulse ◽  
Color Pattern ◽  
Geometric Morphometric ◽  
Geometric Morphometric Analysis ◽  
Local Water ◽  
Relationship Of ◽  
The Relationship ◽  
Shape Changes

Previously recognized color and pattern variants of adult Cichla temensis in Amazon flood pulse river environments reflect the cycling of individuals through seasonal sexual maturity and spawning. Individuals also vary in shape from blocky to fusiform. To determine if shape differences are related to patterns of fat reserve deposition and utilization, and to quantify the relationship of shape with color and pattern variation and life history status, specimens in each of four previously defined grades of color and pattern variation were compared using geometric morphometric techniques. Progressive shape changes occurred between grades independent of sex and correlated to gonosomatic index (GSI). Thin plate spline deformation visualizations indicate that the observed shape differences are related to fat deposition patterns. The seasonal timing of shape change and its link to color pattern variation, sexual maturity and local water level conditions suggests a relationship between the physiological and behavioral characteristics of C. temensis and the cyclical flood pulse pattern of its habitat.

A three-dimensional skull ontogeny in the bobcat (Lynx rufus) (Carnivora: Felidae): a comparison with other carnivores

2015 ◽  
Vol 93 (3) ◽  
pp. 225-237 ◽  
Author(s):  
Valentina Segura
Keyword(s):  
Sexual Maturity ◽  
Three Dimensional ◽  
Morphological Characters ◽  
The Body ◽  
Lynx Rufus ◽  
Large Prey ◽  
Prenatal Period ◽  
Geometric Morphometric ◽  
Geometric Morphometric Analysis ◽  
The Relationship

The maturation of mammalian carnivores from a lactating juvenile to a predatory adult requires a suite of changes in both morphology and behaviour. Bobcats (Lynx rufus (Schreber, 1777)) are medium-sized cats with well-developed skulls to process large prey that can exceed their body mass. An integrated view of the skull ontogeny in the bobcat was developed to detect the relationship between shape, size (on the basis of three-dimensional geometric morphometric analysis), and life history. Dietary changes from juvenile to adults were taken into account and compared with other carnivores. Newborns were different from the remaining age stages in the behavioral and morphological characters examined, which allows us to relate them to the terminal morphology reached during the prenatal period. All findings were related to the reinforcement of the skull and the enhancement of predatory skills in adult bobcats. The final cranial shape is reached in A2 age class, after 2 years of age, and once sexual maturity has been reached. This is a pattern not followed for the rest of carnivores previously studied, which might be related to the capacity of subduing prey that exceed them in size, a behavior not common in felids of the body size of bobcats.

Platelet Shape Change Evoked by Selective Activation of P2X1 Purinoceptors with α,β-Methylene ATP

2001 ◽  
Vol 85 (02) ◽  
pp. 303-308 ◽  
Author(s):  
Michael Rolf ◽  
Charles Brearley ◽  
Martyn Mahaut-Smith
Keyword(s):  
Inhibitory Action ◽  
Light Transmission ◽  
Shape Change ◽  
Second Messengers ◽  
Receptor Activation ◽  
Selective Activation ◽  
The Relationship ◽  
Shape Changes ◽  
Platelet Shape

SummarySimultaneous measurements of [Ca2+]i and light transmission were used to examine the relationship between P2X1 receptor activation and functional platelet responses. The P2X1 agonist α,β-MeATP evoked a transient [Ca2+]i increase and a reversible decrease in light transmission; both responses required external Ca2+ and the nucleotidase apyrase. The transmission response was due to shape change only, verified by scanning electron microscopy and insensitivity to Reopro, a GPIIbIIIa antagonist. α,β-MeATP stimulated smaller shape changes than ADP, however P2X1 responses had a lifespan of <2 h following resuspension in saline and may be considerably larger in vivo. A peak [Ca2+]i increase of >50 nM was required for detectable shape change. Overlap of concentration-response relationships for α,β-MeATP-evoked [Ca2+]i and shape change suggests that other second messengers are not involved. Therefore, the physiological P2X1 agonist ATP can contribute to platelet activation, in contrast to its previously described inhibitory action at metabotropic platelet purinoceptors.

scholarly journals Sexual dimorphism of the mandibular conformational changes in aging human adults: A multislice computed tomographic study by geometric morphometrics

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253564
Author(s):  
Leonor Costa Mendes ◽  
Julien Delrieu ◽  
Claudia Gillet ◽  
Norbert Telmon ◽  
Delphine Maret ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Conformational Changes ◽  
Sexually Dimorphic ◽  
Shape Variation ◽  
Geometric Morphometric ◽  
Computed Tomographic ◽  
Age Related ◽  
Human Adults ◽  
Geometric Morphometric Analysis ◽  
Shape Changes

The aging process has an impact on mandibular bone morphology and can therefore affect shape sexual dimorphism. Understanding the effect of senescence on mandibular shape changes is particularly important to correctly estimate the sex of an individual and predict age-related conformational modifications. The purpose of this study was to assess age-related changes in mandibular shape and sexual dimorphism. The study sample comprised 160 Multi Slice Computed Tomography examinations of individuals aged 40 to 79 years. Geometric morphometric analysis of fourteen osteometric landmarks was used to examine sexual dimorphism and patterns of mandibular shape variation with age. Results showed that mandibular sexual dimorphism of shape remained significant with aging. Conformational changes occurred between 50 and 70 years and were different for male and female individuals. Females presented earlier and more marked age-related shape changes than males. These observations suggest that mandibular senescence is a sexually dimorphic process since its onset, rate, and the areas subjected to conformational changes differ from male to female individuals. Senescence-related changes present substantial variability, and further investigation is required to determine precisely the age that marks their onset.

scholarly journals A geometric morphometric analysis of Arachnoides placenta (Echinoidea: Clypeasteroida): An examination of ontogenetic development and morphological variation

Zoosymposia ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 159-171
Author(s):  
ROBERT E. SWISHER ◽  
JIH-PAI LIN
Keyword(s):  
Developmental Change ◽  
Shape Change ◽  
Adult Life ◽  
Morphologic Change ◽  
Shape Variation ◽  
Minor Variation ◽  
Geometric Morphometric ◽  
Morphometric Analyses ◽  
Geometric Morphometric Analysis ◽  
Sand Dollars

Irregular echinoids, particularly clypeasteroids or “sand dollars”, have obtained highly adaptive morphologies suited to their life habitats. Specimens (n = 26) of a clypeasteroid echinoid Arachnoides placenta were examined to understand how these adaptive morphologies were ontogenetically and developmentally obtained. Ontogenetically, early post-larval juvenile specimens have a pentagonal morphologic outline (known as ambitus) that shifts to a circular or a sub-circular morphology observed in the largest adult specimens. Circular morphology appears optimized for the adult life habitat or niche. Both landmark and semilandmark geometric morphometric methodologies were applied to quantify shape change, ontogenetic variation, and developmental morphology in A. placenta. Ambitus change is concentrated along the interambulacral regions with broader curvature variations occurring across both ambulacral and interambulacral regions. Circular adult morphology was a result of non-isometric shape change concentrated anteriorly with minor variation around posterior margin/periproctal furrow. Interior morphologic change of the petaloids and periproct was also quantified, mainly impacting posterior outline morphology. Minimal deformation of the basicoronal plates was detected, indicating stability during ontogeny. Results indicated that complex, non-isometric allometric shape change, both along the ambitus and interiorly, is required to morph from a pentagonal outline in post-larval juveniles to a circular or sub-circular ambitus morphology in adults. This analysis demonstrates the advantages of both landmark and semilandmark geometric morphometric analyses for quantifying developmental change and shape variation in Clypeasteroida.

The color pattern on a Cretaceous nautiloid from South Dakota

1995 ◽  
Vol 69 (4) ◽  
pp. 785-786 ◽  
Author(s):  
Royal H. Mapes ◽  
Timothy S. Evans
Keyword(s):  
South Dakota ◽  
Color Pattern ◽  
Color Patterns ◽  
Late Mesozoic ◽  
Rare Phenomenon ◽  
Banding Analysis ◽  
Relationship Of ◽  
The Relationship

Preservation of relict color patterns on fossil nautiloid cephalopods is a relatively rare phenomenon. Reports of this phenomenon as summarized by Kobluck and Mapes (1989, table 2) for the Paleozoic indicate that perhaps as many as 32 genera with coiled, orthoconic, and cyrtoconic conchs have been described with relict color patterns. However, reports of Mesozoic occurrences are limited to only Ophionautilus? in the Jurassic (Shimanski, 1962) and Eutrephoceras in the Cretaceous (Shimanski, 1962; Landman, 1982). Cenozoic reports are limited to Aturia in the Tertiary (Foerste, 1930; Shimanski, 1962; Teichert, 1964) and modern Nautilus (see Saunders and Landman, 1987, for an extensive treatment). The reports on both Mesozoic occurrences are limited to description of external conch morphology, detailed appearance of the color patterns, and the relationship of the remnant color pattern to the conch morphology. Indeed, the specimen discussed herein was originally illustrated by Landman (1982, fig. 8), with a caption indicating the presence of possible color banding. Analysis of this Cretaceous specimen allows comparison to Nautilus and provides a suggestion as to the evolution of certain mature color patterns in coiled cephalopods from the late Mesozoic to Recent.

scholarly journals Study TPX-100-5: intra-articular TPX-100 significantly delays pathological bone shape change and stabilizes cartilage in moderate to severe bilateral knee OA

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Dawn McGuire ◽  
Michael Bowes ◽  
Alan Brett ◽  
Neil A. Segal ◽  
Meghan Miller ◽  
...  
Keyword(s):  
Internal Control ◽  
Function Versus ◽  
Shape Change ◽  
Cartilage Thickness ◽  
Cartilage Defects ◽  
Knee Cartilage ◽  
Knee Oa ◽  
To Receive ◽  
The Relationship ◽  
Shape Changes

Abstract Background TPX-100, a promotor of osteoblast and chondroblast differentiation, is a potential osteoarthritis (OA) therapy. This retrospective study compared MRI 3D femoral bone shape changes (B-scores) after intra-articular TPX-100 or placebo and analyzed the relationship between cartilage thickness and bone shape change over 12 months. Methods One hundred and four participants with bilateral moderate to severe knee cartilage defects were randomized to receive TPX-100 (200 mg) or placebo. Each subject’s contralateral placebo-treated knee served as a paired internal control. After MRI quality control, 78/93 subjects (84%; 156 knees) were analyzed for quantitative femoral B-score and cartilage thickness. All analyses were performed centrally, blind to treatment assignment and clinical data. Results TPX-100-treated knees (n = 78) demonstrated a statistically significant decrease in pathologic bone shape change compared with placebo-treated knees at 6 and 12 months: 0.0298 (95% C.I. − 0.037, 0.097) vs 0.1246 (95% C.I. 0.067, 0.182) (P = 0.02), and 0.0856 (95% C.I. 0.013, 0.158) vs. 0.1969 (95% C.I. 0.123, 0.271) (P = 0.01), respectively. The correlation between bone shape change and medial and total tibiofemoral cartilage thickness changes at 12 months was statistically significant in TPX-100-treated knees (P < 0.01). Conclusions This is the first report of a potential therapy demonstrating a significant effect on bone shape measured by B-score in knee OA. These data, in combination with previously reported statistically significant and clinically meaningful improvements in WOMAC physical function versus placebo, support TPX-100 as a candidate for disease modification in knee OA. Trial registration NIH ClinicalTrials.gov, NCT01925261. Registered 15 August 2013

scholarly journals Maternal environment and craniofacial growth: geometric morphometric analysis of mandibular shape changes with in utero thyroxine overexposure in mice

2018 ◽  
Vol 233 (1) ◽  
pp. 46-54 ◽  
Author(s):  
Matthew J. Kesterke ◽  
Margaret A. Judd ◽  
Mark P. Mooney ◽  
Michael I. Siegel ◽  
Mohammed Elsalanty ◽  
...  
Keyword(s):  
Morphometric Analysis ◽  
In Utero ◽  
Craniofacial Growth ◽  
Maternal Environment ◽  
Geometric Morphometric ◽  
Geometric Morphometric Analysis ◽  
Shape Changes
Sign in / Sign up

Export Citation Format

Share Document