Functional Morphology of the Cardiac Jelly in the Tubular Heart of Vertebrate Embryos

The early embryonic heart is a multi-layered tube consisting of (1) an outer myocardial tube; (2) an inner endocardial tube; and (3) an extracellular matrix layer interposed between the myocardium and endocardium, called “cardiac jelly” (CJ). During the past decades, research on CJ has mainly focused on its molecular and cellular biological aspects. This review focuses on the morphological and biomechanical aspects of CJ. Special attention is given to (1) the spatial distribution and fiber architecture of CJ; (2) the morphological dynamics of CJ during the cardiac cycle; and (3) the removal/remodeling of CJ during advanced heart looping stages, which leads to the formation of ventricular trabeculations and endocardial cushions. CJ acts as a hydraulic skeleton, displaying striking structural and functional similarities with the mesoglea of jellyfish. CJ not only represents a filler substance, facilitating end-systolic occlusion of the embryonic heart lumen. Its elastic components antagonize the systolic deformations of the heart wall and thereby power the refilling phase of the ventricular tube. Non-uniform spatial distribution of CJ generates non-circular cross sections of the opened endocardial tube (initially elliptic, later deltoid), which seem to be advantageous for valveless pumping. Endocardial cushions/ridges are cellularized remnants of non-removed CJ.

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Functional Morphology of the Cardiac Jelly in the Tubular Heart of Vertebrate Embryos

10.20944/preprints201901.0312.v1 ◽

2019 ◽

Author(s):

Jörg Männer ◽

Talat Mesud Yelbuz

Keyword(s):

Spatial Distribution ◽

Cross Sections ◽

Embryonic Heart ◽

Endocardial Cushions ◽

Valveless Pumping ◽

Matrix Layer ◽

Heart Looping ◽

Biological Aspects ◽

Vertebrate Embryos ◽

Heart Wall

The early embryonic heart is a multi-layered tube consisting of (1) an outer myocardial tube; (2) an inner endocardial tube; and (3) an extracellular matrix layer interposed between myocardium and endocardium, called “cardiac jelly” (CJ). During the past decades, research on CJ has mainly focused on its molecular and cell biological aspects. This review focuses on the morphological and biomechanical aspects of CJ. Special attention is given to (1) the spatial distribution and fiber architecture of CJ; (2) the morphological dynamics of CJ during the cardiac cycle; and (3) the removal/remodeling of CJ during advanced heart looping stages, which leads to the formation of ventricular trabeculations and endocardial cushions. CJ acts as a hydraulic skeleton displaying striking structural and functional similarities with the mesoglea of jellyfish. CJ not only represents a filler substance, facilitating end-systolic occlusion of the embryonic heart lumen. Its elastic components antagonize the systolic deformations of the heart wall and thereby power the refilling phase of the ventricular tube. Non-uniform spatial distribution of CJ generates non-circular cross sections of the opened endocardial tube (initially elliptic, later deltoid), which seem to be advantageous for valveless pumping. Endocardial cushions arise from non-removed remnants of the original CJ.

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Valveless pumping behavior of the simulated embryonic heart tube as a function of contractile patterns and myocardial stiffness

Biomechanics and Modeling in Mechanobiology ◽

10.1007/s10237-021-01489-7 ◽

2021 ◽

Author(s):

Alireza Sharifi ◽

Alex Gendernalik ◽

Deborah Garrity ◽

David Bark

Keyword(s):

Embryonic Heart ◽

Heart Tube ◽

Myocardial Stiffness ◽

Valveless Pumping

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Extension of Pin-Based Point-Wise Energy Slowing-Down Method for VHTR Fuel with Double Heterogeneity

Energies ◽

10.3390/en14082179 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2179

Author(s):

Tae-Young Han ◽

Jin-Young Cho ◽

Chang-Keun Jo ◽

Hyun-Chul Lee

Keyword(s):

Cross Sections ◽

Cell Model ◽

Unit Cell ◽

Moderation Effect ◽

Slowing Down ◽

Matrix Layer ◽

The Mean ◽

Dancoff Factor ◽

Double Heterogeneity ◽

Very High

For the resonance treatment of a very high temperature reactors (VHTR) fuel with the double heterogeneity, an extension of the pin-based pointwise energy slowing-down method (PSM) was developed and implemented into DeCART. The proposed method, PSM-double heterogeneity (DH), has an improved spherical unit cell model with an explicit tri-structural isotropic (TRISO) model, a matrix layer, and a moderator for reflecting the moderation effect. The moderator volume was analytically derived using the relation of the Dancoff factor and the mean chord length. In the first step, the pointwise homogenized cross-sections for the compact was obtained after solving the slowing down equation for the spherical unit cell. Then, the shielded cross-section for the homogenized fuel compact was generated using the original PSM. The verification calculations were performed for the fuel pins with various packing fractions, compact sizes, TRISO sizes, and fuel temperatures. Additionally, two fuel block problems with very different sizes were examined and the depletion calculation was carried out for investigating the accuracy of the proposed method. They revealed that the PSM-DH has a good performance in the VHTR problems.

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Embryonic development of the heart

Development ◽

10.1242/dev.22.3.333 ◽

1969 ◽

Vol 22 (3) ◽

pp. 333-348

Author(s):

Francis J. Manasek

Keyword(s):

Cell Layer ◽

Embryonic Heart ◽

Outer Cell ◽

Chick Embryos ◽

Myocardial Wall ◽

Undifferentiated Cells ◽

Epicardial Layer ◽

Outer Cell Layer ◽

Heart Wall

The mature heart may be thought of as consisting of three layers, endocardium, myocardium, and an outer investing tissue called the epicardium. During early formation of the tubular heart of chick embryos, at about the 8-somite stage, two tissue layers become clearly discernible with the light microscope: the endocardium and the developing myocardial wall. The outer epicardial layer does not appear until later in development. It is generally accepted that embryonic heart wall or ‘epimyocardium’ is composed of muscle and undifferentiated cells. As its name implies, the epimyocardium is thought to give rise to myocardium and epicardium. Kurkiewicz (1909) suggested that the epicardium was not an epimyocardial derivative but rather is formed from cells originating in the sinus venosus region, which migrate over the surface of the heart. Nevertheless, it has become generally accepted that the outer cell layer of the embryonic heart wall differentiates in situ to give rise to the definitive visceral epicardium (Patten, 1953).

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Kinking and Torsion Can Significantly Improve the Efficiency of Valveless Pumping in Periodically Compressed Tubular Conduits. Implications for Understanding of the Form-Function Relationship of Embryonic Heart Tubes

Journal of Cardiovascular Development and Disease ◽

10.3390/jcdd4040019 ◽

2017 ◽

Vol 4 (4) ◽

pp. 19 ◽

Cited By ~ 5

Author(s):

◽

Keyword(s):

Embryonic Heart ◽

Form Function ◽

Valveless Pumping ◽

Function Relationship ◽

Relationship Of

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Laboratory Study of Corrosion of an Alumina Refractory by Molten Potassium Salts

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.70.65 ◽

2010 ◽

Vol 70 ◽

pp. 65-71 ◽

Cited By ~ 2

Author(s):

Na Li ◽

Leena Hupa ◽

Patrik Yrjas ◽

Mikko Hupa

Keyword(s):

Cross Sections ◽

Molar Ratio ◽

Biomass Combustion ◽

Silicate Matrix ◽

Potassium Salts ◽

Scale Method ◽

Matrix Layer ◽

The Matrix ◽

Alumina Refractory ◽

Refractory Surface

The increasing use of biomass and waste derived fuels in combustion challenges the chemical durability of refractories. Durability of an alumina refractory was studied in a chemically aggressive environment. A mixture of potassium chloride and carbonate (molar ratio 1:9) was placed on the sample and heated at 700-1000°C in an electric laboratory furnace in air for one week. Cross-sections of the samples were studied by SEM-EDXA to determine penetration of potassium in the refractory. Potassium was found only in the silicate matrix phase of the alumina refractory. Penetration of potassium decreased steeply from the surface to 1 mm, after which the decrease was linear but varied with temperature. At 700 and 800°C the thickness of the matrix layer that had reacted with potassium was 3 mm, while the layer was thinner at 900 and 1000°C. At the higher temperatures a glassy layer consisting of K2O, Na2O, CaO and SiO2 formed on the refractory surface. At 900°C the thickness of the surface layer was of 10μm, while a 200μm layer was measured at 1000°C. The procedure used in this work can be used to develop a laboratory scale method to be used to study corrosion of refractories in biomass combustion devices.

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Patterns of muscular strain in the embryonic heart wall

Developmental Dynamics ◽

10.1002/dvdy.22053 ◽

2009 ◽

Vol 238 (8) ◽

pp. spcone-spcone

Author(s):

Brooke J. Damon ◽

Mathieu Rémond ◽

Michael R. Bigelow ◽

Thomas C. Trusk ◽

Wenjie Xie ◽

...

Keyword(s):

Embryonic Heart ◽

Heart Wall

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AUTOMATIC CONTOURING USING BICUBIC FUNCTIONS

Geophysics ◽

10.1190/1.1440290 ◽

1972 ◽

Vol 37 (4) ◽

pp. 669-674 ◽

Cited By ~ 19

Author(s):

R. C. Hessing ◽

Henry K. Lee ◽

Alan Pierce ◽

Eldon N. Powers

Keyword(s):

Spatial Distribution ◽

Cross Sections ◽

Digital Computer ◽

Smooth Surface ◽

Contour Line ◽

Contour Maps ◽

Volume Calculations ◽

Contour Lines ◽

Data Points ◽

Automatic Contouring

A method is described for using a digital computer to construct contour maps automatically. Contour lines produced by this method have correct relations to given discrete data points regardless of the spatial distribution of these points. The computer‐generated maps are comparable to those drawn manually. The region to be contoured is divided into quadrilaterals whose vertices include the data points. After supplying values at each of the remaining vertices by using a surface‐fitting technique, bicubic functions are constructed on each quadrilateral to form a smooth surface through the data points. Points on a contour line are obtained from these surfaces by solving the resulting cubic equations. The bicubic functions may be used for other calculations consistent with the contour maps, such as interpolation of equally spaced values, calculation of cross‐sections, and volume calculations.

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Nanoparticles in Lustre Reconstructions

MRS Proceedings ◽

10.1557/proc-852-oo8.5 ◽

2004 ◽

Vol 852 ◽

Cited By ~ 3

Author(s):

P. Fredrickx ◽

J. Verbeeck ◽

D. Schryvers ◽

D. Hélary ◽

E. Darque-Ceretti

Keyword(s):

Spatial Distribution ◽

Cross Sections ◽

Ag Nanoparticles ◽

Cu Nanoparticles ◽

The Difference

ABSTRACTIt is increasingly apparent that the spatial distribution of Ag and Cu nanoparticles in lustre glazes is an important factor in determining the colour displayed by the decoration. Using STEM-EDX of cross sections, this distribution can easily be imaged, as is demonstrated in two modern reconstructions of lustre decorations from Granada, Spain. On the nanoscale, the difference in colour can be related to a different spatial distribution of the Ag and Cu particles, with the brownish gold variant consisting of a top layer of Ag nanoparticles with an underlying layer of Cu nanoparticles while in the yellowish golden lustre Cu specks are unevenly dispersed.

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