Modelling skin surface areas involved in water transfer in the Palmate Newt (Lissotriton helveticus)

2014 ◽  
Vol 92 (8) ◽  
pp. 707-714 ◽  
Author(s):  
Thomas Wardziak ◽  
Laurent Oxarango ◽  
Sébastien Valette ◽  
Laurent Mahieu-Williame ◽  
Pierre Joly
Keyword(s):  
Surface Area ◽  
Skin Surface ◽  
Water Transfer ◽  
The Body ◽  
Body Volume ◽  
3D Analysis ◽  
Evaporative Water ◽  
Surface Areas ◽  
Lissotriton Helveticus ◽  
Palmate Newt

Magnetic resonance imaging (MRI) based 3D reconstructions were used to derive accurate quantitative data on body volume and functional skin surface areas involved in water transfer in the Palmate Newt (Lissotriton helveticus (Razoumovsky, 1789)). Body surface area can be functionally divided into evaporative surface area that interacts with the atmosphere and controls the transepidermal evaporative water loss (TEWL); ventral surface area in contact with the substratum that controls transepidermal water absorption (TWA); and skin surface area in contact with other skin surfaces when amphibians adopt water-conserving postures. We generated 3D geometries of the newts via volume-rendering by a “segmentation” process carried out using a graph-cuts algorithm and a Web-based interface. The geometries reproduced the two postures adopted by the newts, i.e., an I-shaped posture characterized by a straight body without tail coiling and an S-shaped posture where the body is huddled up with the tail coiling along it. As a guide to the quality of the surface area estimations, we compared measurements of TEWL rates between living newts and their agar replicas (reproducing their two postures) at 20 °C and 60% relative humidity. Whereas the newts did not show any physiological adaptations to restrain evaporation, they expressed an efficient S-shaped posture with a resulting water economy of 22.9%, which is very close to the 23.6% reduction in evaporative surface area measured using 3D analysis.

Inhibiting ventilatory evaporation produces an adaptive increase in cutaneous evaporation in mourning doves Zenaida macroura

1999 ◽  
Vol 202 (21) ◽  
pp. 3021-3028 ◽  
Author(s):  
T.C. Hoffman ◽  
G.E. Walsberg
Keyword(s):  
Skin Surface ◽  
The Body ◽  
Evaporative Heat Loss ◽  
Evaporative Water ◽  
Zenaida Macroura ◽  
Ambient Temperatures ◽  
Rapid Adjustment ◽  
Mourning Doves ◽  
A Minor ◽  
Cutaneous Evaporation

We tested the hypothesis that birds can rapidly change the conductance of water vapor at the skin surface in response to a changing need for evaporative heat loss. Mourning doves (Zenaida macroura) were placed in a two-compartment chamber separating the head from the rest of the body. The rate of cutaneous evaporation was measured in response to dry ventilatory inflow at three ambient temperatures and in response to vapor-saturated ventilatory inflow at two ambient temperatures. At 35 degrees C, cutaneous evaporation increased by 72 % when evaporative water loss from the mouth was prevented, but no increase was observed at 45 degrees C. For both dry and vapor-saturated treatments, cutaneous evaporation increased significantly with increased ambient temperature. Changes in skin temperature made only a minor contribution to any observed increase in cutaneous evaporation. This indicates that Z. macroura can effect rapid adjustment of evaporative conductance at the skin in response to acute change in thermoregulatory demand.

scholarly journals New Mathematical Model for the Surface Area of the Left Ventricle by the Truncated Prolate Spheroid

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
José Sérgio Domingues ◽  
Marcos de Paula Vale ◽  
Carlos Barreira Martinez
Keyword(s):  
Mathematical Model ◽  
Left Ventricle ◽  
Surface Area ◽  
Age Groups ◽  
Prolate Spheroid ◽  
The Body ◽  
Surface Areas ◽  
Heart Chamber ◽  
Strong Linear Correlation ◽  
Superficial Area

The main aim of this study was the formula application of the superficial area of a truncated prolate spheroid (TPS) in Cartesian coordinates in obtaining a cardiac parameter that is not so much discussed in literature, related to the left ventricle (LV) surface area of the human heart, by age and sex. First we obtain a formula for the area of a TPS. Then a simple mathematical model of association of the axes measures of a TPS with the axes of the LV is built. Finally real values of the average dimensions of the humans LV are used to measure surface areas approximations of this heart chamber. As a result, the average superficial area of LV for normal patients is obtained and it is observed that the percentage differences of areas between men and women and their consecutive age groups are constant. A strong linear correlation between the obtained areas and the ventricular volumes normalized by the body areas was observed. The obtained results indicate that the superficial area of the LV, besides enabling a greater knowledge of the geometrical characteristics of the human LV, may be used as one of the normality cardiac verification criteria and be useful for medical and biological applications.

scholarly journals Surface Area of Patellar Facets: Inferential Statistics in the Iraqi Population

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Ahmed Al-Imam ◽  
Zaid Al-Zamili ◽  
Rawan Omar
Keyword(s):  
Surface Area ◽  
Three Dimensional ◽  
Statistical Correlation ◽  
Morphometric Parameters ◽  
The Body ◽  
Sesamoid Bone ◽  
Inferential Statistics ◽  
Surface Areas ◽  
Dimensional Complexity ◽  
Image Analyses

Background. The patella is the largest sesamoid bone in the body; its three-dimensional complexity necessitates biomechanical perfection. Numerous pathologies occur at the patellofemoral unit which may end in degenerative changes. This study aims to test the presence of statistical correlation between the surface areas of patellar facets and other patellar morphometric parameters. Materials and Methods. Forty dry human patellae were studied. The morphometry of each patella was measured using a digital Vernier Caliper, electronic balance, and image analyses software known as ImageJ. The patellar facetal surface area was correlated with patellar weight, height, width, and thickness. Results. Inferential statistics proved the existence of linear correlation of total facetal surface area and patellar weight, height, width, and thickness. The correlation was strongest for surface area versus patellar weight. The lateral facetal area was found persistently larger than the medial facetal area, the p value was found to be <0.001 (one-tailed t-test) for right patellae, and another significant p value of < 0.001 (one-tailed t-test) was found for left patellae. Conclusion. These data are vital for the restoration of the normal biomechanics of the patellofemoral unit; these are to be consulted during knee surgeries and implant designs and can be of an indispensable anthropometric, interethnic, and biometric value.

Regional body surface area of sheep

1973 ◽  
Vol 81 (3) ◽  
pp. 429-432 ◽  
Author(s):  
J. W. Bennett
Keyword(s):  
Body Weight ◽  
Surface Area ◽  
Tritiated Water ◽  
Skin Surface ◽  
Lower Leg ◽  
Single Measure ◽  
Body Dimensions ◽  
Merino Sheep ◽  
Surface Areas ◽  
Water Space

SUMMARYTwenty-three shorn, adult Merino sheep weighing 22·6–63·1 kg were killed and total skin surface area and eight regional skin surface areas measured after skinning. Bodyfat content (1·9–43·6% of body weight) was estimated from the tritiated-water space and body dimensions were recorded before slaughter.Body weight was the best single measure for predicting total area and regional areas, and little advantage was gained by using multiple regressions incorporating body weight, fat content and body dimensions. Proportional surface areas of all regions except the neck were significantly related to body weight; positively for the trunk, and negatively for the ear, lower leg, upper leg and head. Equations relating regional surface area (% total area) to body weight are presented.

scholarly journals Born With Bristles: New Insights on the Kölliker’s Organs of Octopus Skin

2021 ◽  
Vol 8 ◽  
Author(s):  
Roger Villanueva ◽  
Montserrat Coll-Lladó ◽  
Laure Bonnaud-Ponticelli ◽  
Sergio A. Carrasco ◽  
Oscar Escolar ◽  
...  
Keyword(s):  
Surface Area ◽  
Body Surface Area ◽  
Body Surface ◽  
Early Life ◽  
Skin Surface ◽  
The Body ◽  
Octopus Vulgaris ◽  
Mode Of Life ◽  
Modes Of Life ◽  
Hatchling Size

The entire skin surface of octopus embryos, hatchlings and juveniles bears scattered tufts of tiny chitinous setae within small pockets, from which they can be everted and retracted. Known as Kölliker’s organs (KO), they disappear before the subadult stage. The function of these structures during the early life of the octopus is unknown, despite having been first described nearly two centuries ago. To investigate these organs further, general trends in size of KO distribution and density were analyzed in hatchlings and juveniles of 17 octopod species from all oceans, representing holobenthic, holopelagic and meropelagic modes of life. The size of the KO is fairly constant across species, unrelated to mode of life or hatchling size. The density of KO is similar on ventral and dorsal body surfaces, but hatchlings of smaller size tend to have a higher density of KO on the aboral surface of the arms. Analysis of a series of post-hatching Octopus vulgaris shows KO size to be constant throughout ontogeny; it is therefore a consistent structure during the octopus early life from planktonic hatchling to benthic juvenile. New KO are generated on the skin of the arm tips during the planktonic period and initial benthic lives of juveniles. Their density, on both the mantle and arms, gradually decreases as the octopus grows. In older benthic juveniles, the KO degrades, losing its setae and the base of its follicle becomes exposed as a nearly circular stump of muscle. It is estimated that fully everted KO increase the body surface area by around two-thirds compared to when the KO are retracted. This modular mechanism of body surface extension and roughness probably influences flow-related forces such as drag and propulsion of the moving surface of the young octopus while it is of small size with a relatively large surface area. In addition, the distribution of these organs on the aboral surface of the arms of the octopus and their birefringent properties suggest a role in camouflage. Further research is needed to test these hypotheses of KO function in live animals.

Regional surface areas of spontaneously hypertensive and Wistar-Kyoto rats

1987 ◽  
Vol 62 (2) ◽  
pp. 752-755 ◽  
Author(s):  
W. A. Lyzak ◽  
W. S. Hunter
Keyword(s):  
Skin Temperature ◽  
Surface Area ◽  
Skin Surface ◽  
Total Surface Area ◽  
Mean Skin Temperature ◽  
Spontaneously Hypertensive ◽  
Wky Rats ◽  
Surface Areas ◽  
Dental Impression ◽  
Wistar Kyoto

Regional skin surface area and region-specific weighting factors for calculating mean skin temperature have not been determined for the rat. Therefore, measurements were made of total skin surface area segmented into five regions of 12 spontaneously hypertensive (SHR) and 12 normotensive Wistar-Kyoto (WKY) rats. SHR's were selected because chronically elevated core temperature and reduced ability of SHR's to withstand heat stress make them of interest for thermoregulatory studies. Area was determined by coating the skin with rubber base dental impression material, then measuring the area of the coating. The relationship between total skin surface area and mass of SHR's was not different from that of WKY's and is described by the equation SA = 8.62 M0.67. However, the ears of SHR's had larger surface area and their tails smaller surface area than those of WKY's. For the combined groups, the proportion of total surface area of the regions was as follows: ears, 0.022; front feet, 0.017; hind feet, 0.040; tail, 0.100; central skin, 0.826. These data provide a basis for calculating skin surface area, mean skin temperature, and related values for SHR and WKY rats.

scholarly journals Physiological determinants of the pulmonary filtration coefficient

2008 ◽  
Vol 295 (2) ◽  
pp. L235-L237 ◽  
Author(s):  
James C. Parker ◽  
Mary I. Townsley
Keyword(s):  
Vascular Permeability ◽  
Surface Area ◽  
The Body ◽  
Filtration Coefficient ◽  
Lung Weight ◽  
Surface Areas ◽  
Fluid Permeability ◽  
Pulmonary Capillary ◽  
Body Weights ◽  
Oxygen Requirements

Current emphasis on translational application of genetic models of lung disease has renewed interest in the measurement of the gravimetric filtration coefficient ( Kf) as a means to assess vascular permeability changes in isolated perfused lungs. The Kf is the product of the hydraulic conductivity and the filtration surface area, and is a sensitive measure of vascular fluid permeability when the pulmonary vessels are fully recruited and perfused. We have observed a remarkable consistency of the normalized baseline Kf values between species with widely varying body weights from mice to sheep. Uniformity of Kf values can be attributed to the thin alveolar capillary barrier required for gas exchange and the conserved matching of lung vascular surface area to the oxygen requirements of the body mass. An allometric correlation between the total lung filtration coefficient ( Kf,t) and body weight in several species ( r2 = 1.00) had a slope that was similar to those reported for alveolar and pulmonary capillary surface areas and pulmonary diffusion coefficients determined by morphometric methods in these species. A consistent Kf is dependent on accurately separating the filtration and vascular volume components of lung weight gain, then Kf is a consistent and repeatable index of lung vascular permeability.

Cell morphology, volume, and surface area determinations from multilevel contouring within HVEM micrographs of serial sections and whole-cell mounts

1987 ◽  
Vol 45 ◽  
pp. 588-589
Author(s):  
M. Marko ◽  
A. Leith ◽  
D. Parsons
Keyword(s):  
Surface Area ◽  
Electron Micrographs ◽  
Cell Morphology ◽  
Individual Variation ◽  
Serial Section ◽  
Stereo Pair ◽  
Complex Structures ◽  
Serial Sections ◽  
Surface Areas ◽  
Computer Based

The use of serial sections and computer-based 3-D reconstruction techniques affords an opportunity not only to visualize the shape and distribution of the structures being studied, but also to determine their volumes and surface areas. Up until now, this has been done using serial ultrathin sections.The serial-section approach differs from the stereo logical methods of Weibel in that it is based on the Information from a set of single, complete cells (or organelles) rather than on a random 2-dimensional sampling of a population of cells. Because of this, it can more easily provide absolute values of volume and surface area, especially for highly-complex structures. It also allows study of individual variation among the cells, and study of structures which occur only infrequently.We have developed a system for 3-D reconstruction of objects from stereo-pair electron micrographs of thick specimens.

The use of Body Surface Index as a Better Clinical Health indicators Compare to Body Mass Index and Body Surface Area for Clinical Application

2018 ◽  
pp. 131-136
Author(s):  
Shirazu I. ◽  
Theophilus. A. Sackey ◽  
Elvis K. Tiburu ◽  
Mensah Y. B. ◽  
Forson A.
Keyword(s):  
Surface Area ◽  
Body Surface Area ◽  
Clinical Application ◽  
Body Surface ◽  
Body Height ◽  
Health Indicators ◽  
The Body ◽  
Body Parameters ◽  
The Relationship ◽  
Individual Body

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.

scholarly journals Digital 3D models of theropods for approaching body-mass distribution and volume

2021 ◽  
Author(s):  
Matías Reolid ◽  
Francisco J. Cardenal ◽  
Jesús Reolid
Keyword(s):  
Body Length ◽  
Heat Dissipation ◽  
Volume Ratio ◽  
3D Models ◽  
The Body ◽  
3D Analysis ◽  
Skull Length ◽  
Knowing That ◽  
Fossil Bones ◽  
Primitive Forms

AbstractThe aim of this work is to obtain diverse morphometric data from digitized 3D models of scientifically accurate palaeoreconstructions of theropods from eight representative families. The analysed polyvinyl chloride (PVC) models belong to the genera Coelophysis, Dilophosaurus, Ceratosaurus, Allosaurus, Baryonyx, Carnotaurus, Giganotosaurus, and Tyrannosaurus. The scanned 3D models were scaled considering different body-size estimations of the literature. The 3D analysis of these genera provides information on the skull length and body length that allows for recognition of major evolutionary trends. The skull length/body length in the studied genera increases according with the size of the body from the smallest Coelophysis with a ratio of 0.093 to ratios of 0.119–0.120 for Tyrannosaurus and Giganotosaurus, the largest study theropods. The study of photogrammetric 3D models also provides morphometric information that cannot be obtained from the study of bones alone, but knowing that all reconstructions begin from the fossil bones, such as the surface/volume ratio (S/V). For the studied theropod genera surface/volume ratio ranges from 35.21 for Coelophysis to 5.55 for Tyrannosaurus. This parameter, closely related to the heat dissipation, help in the characterization of the metabolism of extinct taxa. Accordingly, slender primitive forms of the Early Jurassic (i.e. Coelophysis and Dilophosaurus) had relatively smaller skulls and higher mass-specific metabolic rates than the robust large theropods of the Cretaceous (i.e. Giganotosaurus and Tyrannosaurus). This work presents a technique that, when applied to proper dinosaur models, provides extent and accurate data that may help in diverse study areas within the dinosaur palaeontology and palaeobiology.

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