scholarly journals Wheels within wheels, Nested Function-value Traits as a Tool for Modeling Ontogeny

2021 ◽  
Author(s):  
John G. Hodge ◽  
Andrew N. Doust
Keyword(s):  
Abrupt Change ◽  
Functional Unit ◽  
General Trend ◽  
Shape Change ◽  
Comparative Morphology ◽  
The Body ◽  
Developmental Genetics ◽  
Allometric Relationships ◽  
Order Function ◽  
Individual Function

AbstractPlant morphologies exhibit a wide array of outcomes that have evolved as a consequence adapting to a wide array of ecological pressures. These disparate morphologies have provided a rich field for comparative morphologists, developmental biologists, and geneticists to explore. Ultimately the array of variation observed in nature across different plant species is built on the same functional unit, the phytomer, which is composed of a leaf, a node, and an internode. Sequentially produced phytomers exhibit heteroblasty, that is, a gradual or abrupt change in shape, either due to size changes or changes due to reproductive phase. The progression of shape change over time is often indirectly measured by sampling several stages of plant growth and comparing allometric relationships between shape variables. However, a more precise method is to use an absolute time scale and measure shape change of sequential organs directly. In this study we use such time-dependent measurements to build a general model of organ growth for several Setaria genotypes, for both leaves and internodes. We term this the second-order function-value trait (2FVT) model, because it generalizes individual function-value trait models generated for each organ. This model reduces phenotypic noise by averaging the general trend of ontogeny and provides a quantitative tool to describe where and when phenotypic shifts occur during the ontogenies of different genotypes. The ability to recognize how ontogenetic variation is distributed within equivalent positions of the body plan at the interspecific level can be used as a tool to explore various questions related to growth and form in plants both for comparative morphology and developmental genetics.

Monitoring dynamic breast measurements obtained from 4D body scanning

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jie Pei ◽  
Linsey Griffin ◽  
Susan P. Ashdown ◽  
Jintu Fan
Keyword(s):  
General Trend ◽  
Shape Change ◽  
New Technology ◽  
Left Knee ◽  
The Body ◽  
Linear Measurements ◽  
Content Type ◽  
Body Scanning ◽  
Significant Difference ◽  
3D Scans

PurposeThe purpose of this study is to investigate the shape change of breast during movement to inform product development of bras and other female wearable products.Design/methodology/approachUsing the latest 4D body scanning technology, the authors monitored the change of seven non-circumferential breast measurements, including four linear measurements (widths, depth, etc.) and three angular measurements, across nine dynamic scans of a complete gait cycle during running. A series of statistical analysis were conducted to thoroughly investigate the measurement values in dynamic states compared with values extracted from static 3D scans.FindingsMajor findings are as follows: (1) For width-underbust, chest-depth, vertical-acromion and angle ABD, more than half of the dynamic frames presents a significant difference with the static frame. (2) Width-underbust and chest-depth measured in static can underestimate the actual values under motion. (3) vertical-acromion presents a W-shaped general trend for the nine dynamic frames with peaks observed at the keyframes (i.e. when a participant's right or left knee bends the most and rises to its highest level) and lows at the intermediate frames. (4) Angle ABD and angle BAD both present an M-shaped general trend, the exact opposite of a W-shaped trend.Originality/valueWhile 3D body scanning and motion capture systems have both contributed significantly to the study of breast, 4D body scanning incorporates the advantages of both technologies and captures the 3D surface of the body during movement at each instant moment. This is one of the first studies that adopt the new technology for apparel applications.

scholarly journals Morphological Features Of The Immune Structures Of The Thin Intestine Of Laboratory Animals With Various Characters Of Nutrition

2020 ◽  
Vol 2 (09) ◽  
pp. 72-74
Author(s):  
Khusanov Erkin ◽  
Ortikbaeva Nilufar ◽  
Korzhavov Sherali
Keyword(s):  
Small Intestine ◽  
Digestive Tract ◽  
Structural Organization ◽  
Morphological Changes ◽  
Comparative Morphology ◽  
Morphological Features ◽  
The Body ◽  
Laboratory Animals ◽  
Chemical Processing ◽  
Digestive Tube

The nutritional nature of mammals, which has developed during a long evolution, leads to adaptive - morphological changes in their digestive tract and its immune structures, although the general laws of their structural organization are identical. The literature has data on the study of the immune structures of the small intestine under normal conditions and under the influence of certain factors. In the structure of immune structures there are numerous parallelisms, however, in each class of vertebrates, complication of this organization is achieved independently. The small intestine is an important section of the digestive tube, where the final chemical processing of the chyme and the absorption of nutrients into the body take place. However, the comparative morphology of the immune structures of the small intestine in mammals with different nutrition patterns remains poorly understood.

Comparative morphology of the body wall in flatworms (Platyhelminthes)

2004 ◽  
Vol 82 (2) ◽  
pp. 194-210 ◽  
Author(s):  
Seth Tyler ◽  
Matthew Hooge
Keyword(s):  
Body Wall ◽  
Comparative Morphology ◽  
The Body ◽  
Wall Structure ◽  
Cell Renewal ◽  
Free Living ◽  
Special Adaptation ◽  
Continuous Sheet ◽  
The One ◽  
Taxonomic Groups

The soft-bodied nature of the platyhelminths is due largely to the structure of the body wall and its lack of sclerotic elements such as cuticle. Free-living members, i.e., most turbellarians, show considerable variety, but the basic form of the body wall comprises a simple ciliated epithelium overlying a network of muscles. We illustrate this body wall structure in a representative typhloplanoid rhabditophoran and discuss variations in representatives of the Acoela, Catenulida, and other free-living rhabditophorans. The major parasitic groups of platyhelminths, the rhabditophoran Neodermata, follow a developmental pattern that replaces a similar ciliated epidermis in a larval stage with a specialized epidermis called a neodermis, which is assumed to be key to their success as parasites. This neodermis consists of a syncytium that covers the body in a continuous sheet connected to perikarya that lie below the body wall musculature. The neodermis can be seen as a special adaptation of a developmental mechanism common to all platyhelminths, in which epidermal growth and renewal are accomplished by replacement cells originating beneath the body wall. The cell type responsible for all cell renewal, including body wall renewal, in platyhelminths is the neoblast, and its presence may be the one autapomorphic character that unites all taxonomic groups of platyhelminths.

Investigation of Shapes and Extinction Limits of Premixed Flames in Large Centrifugal Acceleration Field

2012 ◽  
Vol 455-456 ◽  
pp. 327-333
Author(s):  
Jin Xiang Wu ◽  
En Yu Wang ◽  
Lian Sheng Liu ◽  
Xiang Gou
Keyword(s):  
Coriolis Force ◽  
Gas Flow ◽  
Body Force ◽  
Shape Change ◽  
The Body ◽  
Liquefied Petroleum Gas ◽  
Centrifugal Acceleration ◽  
Acceleration Field ◽  
Tangent Direction ◽  
Flame Shape

This paper presents the influence of the body-force in large centrifugal acceleration field on the shapes and extinction limits of the premixed flame of liquefied petroleum gas (LPG) and air. Experiments of combustion in various centrifugal acceleration fields were performed. The results indicate that the magnitude of the resultant body-force, composed mainly of centrifugal force and Coriolis force, is not the only cause of the extinction of flames, but the direction between the resultant body-force and jet direction of the premixed gases plays more important role. Coriolis force, which is always perpendicular to jet direction of the gases, results in the flame turning to sides of the nozzle, even extinction. The buoyancy effect is the mainly element to make the flame shape change: shorten, lengthen or deflect, and improve or weaken combustion. It is favorable for stability of the flame as the included angle of rotating tangent direction to gas flow jet direction is positive.

scholarly journals Gait transitions in simulated reduced gravity

2011 ◽  
Vol 110 (3) ◽  
pp. 781-788 ◽  
Author(s):  
Yuri P. Ivanenko ◽  
Francesca Sylos Labini ◽  
Germana Cappellini ◽  
Velio Macellari ◽  
Joseph McIntyre ◽  
...  
Keyword(s):  
Inverted Pendulum ◽  
Abrupt Change ◽  
The Body ◽  
Reduced Gravity ◽  
Altered Gravity ◽  
Transition Speed ◽  
Simulation Techniques ◽  
Significant Prolongation ◽  
Gait Parameters ◽  
Gait Transitions

Gravity has a strong effect on gait and the speed of gait transitions. A gait has been defined as a pattern of locomotion that changes discontinuously at the transition to another gait. On Earth, during gradual speed changes, humans exhibit a sudden discontinuous switch from walking to running at a specific speed. To study the effects of altered gravity on both the stance and swing legs, we developed a novel unloading exoskeleton that allows a person to step in simulated reduced gravity by tilting the body relative to the vertical. Using different simulation techniques, we confirmed that at lower gravity levels the transition speed is slower (in accordance with the previously reported Froude number ∼0.5). Surprisingly, however, we found that at lower levels of simulated gravity the transition between walking and running was generally gradual, without any noticeable abrupt change in gait parameters. This was associated with a significant prolongation of the swing phase, whose duration became virtually equal to that of stance in the vicinity of the walk-run transition speed, and with a gradual shift from inverted-pendulum gait (walking) to bouncing gait (running).

scholarly journals The Biophysical Modeling of the Nephrogenesis in the Perinatal Periods

2020 ◽  
Vol 5 (3) ◽  
Keyword(s):  
Kidney Function ◽  
Gestational Age ◽  
Cell Walls ◽  
Functional Unit ◽  
The Body ◽  
Time Interval ◽  
Biophysical Modeling ◽  
Nephron Number ◽  
Microscopic Picture ◽  
The One

Our experiments analyzed the microscopic picture of kidneys of patients who died during gestational age or infancy. We wanted to investigate nephrogenesis in its ontogenetic development. We only conducted the analysis until the age of three, because the one million nephron number characteristic of the kidney in adulthood is already developed by the age of three. This perinatal time interval was divided into five periods. Intrauterine are the early fetal (3–5 months) and late fetal periods, neonates (0–1 months), infants (1–12 months) and young children (1–3 years). The specific case numbers are not taken into account, only general remarks are communicated. We found that the structural and functional unit of the kidney is the nephron, which undergoes three initial stages: pro-, meso- and metanephros. There are two periods of accumulation: late fetal and infant age. After birth, the number of incomplete renal corpuscles is negligible. Nephrogenesis occurs from the outside to the inside. By the age of three, the volume of the cortex doubles that of the marrow. In further periods of ontogenesis, the nephron count remains unchanged, only the volume of the nephrons increases. When modelling kidney function, we found that the body is “resting” some of the nephrons, because it is during this time that the cell walls resulting from cavitation are regenerated.

scholarly journals Neuromesodermal Progenitors: A Basis for Robust Axial Patterning in Development and Evolution

2021 ◽  
Vol 8 ◽  
Author(s):  
Ramkumar Sambasivan ◽  
Benjamin Steventon
Keyword(s):  
Cell Fate ◽  
Regulatory Networks ◽  
Shape Change ◽  
The Body ◽  
Body Axis ◽  
Paraxial Mesoderm ◽  
Posterior Aspect ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Multiple Regions

During early development the vertebrate embryo elongates through a combination of tissue shape change, growth and progenitor cell expansion across multiple regions of the body axis. How these events are coordinated across the length of the embryo to generate a well-proportioned body axis is unknown. Understanding the multi-tissue interplay of morphogenesis, growth and cell fate specification is essential for us to gain a complete understanding how diverse body plans have evolved in a robust manner. Within the posterior region of the embryo, a population of bipotent neuromesodermal progenitors generate both spinal cord and paraxial mesoderm derivatives during the elongation of the vertebrate body. Here we summarize recent data comparing neuromesodermal lineage and their underlying gene-regulatory networks between species and through development. We find that the common characteristic underlying this population is a competence to generate posterior neural and paraxial mesoderm cells, with a conserved Wnt/FGF and Sox2/T/Tbx6 regulatory network. We propose the hypothesis that by maintaining a population of multi-germ layer competent progenitors at the posterior aspect of the embryo, a flexible pool of progenitors is maintained whose contribution to the elongating body axis varies as a consequence of the relative growth rates occurring within anterior and posterior regions of the body axis. We discuss how this capacity for variation in the proportions and rates of NM specification might have been important allowing for alterations in the timing of embryo growth during evolution.

scholarly journals Hex Hox: De Novo Transcriptome Assembly and Embryonic Hox Gene Expression in the Burrowing Mayfly Hexagenia Limbata (Ephemeridae)

2021 ◽  
Author(s):  
Christopher J Gonzalez ◽  
Tobias R Hildebrandt ◽  
Brigid C O'Donnell
Keyword(s):  
Hox Genes ◽  
Transcriptome Assembly ◽  
Expression Profiles ◽  
Expression Patterns ◽  
Body Plan ◽  
The Body ◽  
Phylogenetic Position ◽  
Developmental Genetics ◽  
Early Instar ◽  
Hexagenia Limbata

Abstract Background: Hox genes are key regulators of appendage development in the insect body plan. The body plan of Mayfly (Ephemeroptera) nymphs differs due to the presence of evolutionarily significant abdominal appendages called gills. Despite mayflies’ basal phylogenetic position and novel morphology amongst insects, little is known of their developmental genetics. Here we present an annotated transcriptome for the mayfly Hexagenia limbata, with annotated sequences for putative Hox peptides and embryonic expression profiles for the Hox genes Antp and Ubx/abd-A. Results: Transcriptomic sequencing of early instar H. limbata nymphs yielded a high-quality assembly of 83,795 contigs, of which 22,975 were annotated against Folsomia candida, Nilaparvata lugens, Zootermopsis nevadensis and UniRef90 protein databases. Peptide annotations included eight of the ten canonical Hox genes (lab, pb, Dfd, Scr, Antp, Ubx, abd-A and Abd-B), most of which contained all functional domains and motifs conserved in insects. Expression patterns of Antp and Ubx/abd-A in H. limbata were visualized from early to late embryogenesis, and are also highly conserved with patterns reported for other non-holometabolous insects.Conclusions: We present evidence that both H. limbata Hox peptide sequences and embryonic expression patterns for Antp and Ubx/abd-A are extensively conserved with other insects. These findings suggest mayfly Antp and Ubx/abd-A play similar appendage promoting and repressing roles in the thorax and abdomen, respectively. The identified expression of Ubx and abd-A in early instar nymphs further suggests that mayfly gill development is not subject to Ubx or abd-A repression. Previous studies have shown that insect Ubx and abd-A repress appendages by inhibiting their distal structures, which can permit the development of proximal appendage types. In line with past morphology-based work, we propose that mayfly gills are proximal appendage structures, possibly homologous to the proximal appendage structures of crustaceans.

Constraint-Based Synthesis of Shape-Morphing Structures in Virtual Reality

2010 ◽  
Author(s):  
Judy M. Vance ◽  
Denis Dorozhkin
Keyword(s):  
Virtual Reality ◽  
Rigid Body ◽  
Method Development ◽  
Compliant Mechanisms ◽  
Design Method ◽  
Shape Change ◽  
The Body ◽  
Motion Path ◽  
Primary Methods ◽  
Shape Morphing

This manuscript outlines a novel approach to the design of compliant shape-morphing structures using constraint-based design method. Development of robust methods for designing shape-morphing structures is the focus of multiple current research projects, since the ability to modify geometric shapes of the individual system components, such as aircraft wings and antenna reflectors, provides the means to affect the performance of the corresponding mechanical systems. Of particular interest is the utilization of compliant mechanisms to achieve the desired adaptive shape change characteristics. Compliant mechanisms, as opposed to the traditional rigid link mechanisms, achieve motion guidance via the compliance and deformation of the mechanism’s members. The goal is to design a single-piece flexible structure capable of morphing a given curve or profile into a target curve or profile while utilizing the minimum number of actuators. The two primary methods prevalent in the design community at this time are the pseudo-rigid body method (PRBM) and the topological synthesis. Unfortunately these methods either tend to suffer from a poor ability to generate potential solutions (being more suitable for the analysis of existing structures) or are susceptible to overly-complex solutions. By utilizing the constraint-based design method (CBDM) we aim to address those shortcomings. The concept of CBDM has generally been confined to the Precision Engineering community and is based on the fundamental premise that all motions of a rigid body are determined by the position and orientation of the constraints (constraint topology) which are placed upon the body. Any mechanism motion path may then be defined by the proper combination of constraints. In order to apply the CBDM concepts to the design and analysis of shape-morphing compliant structures we propose a tiered design method that relies on kinematics, finite element analysis, and optimization. By discretizing the flexible element that comprises the active shape surface at multiple points in both the initial and the target configurations and treating the resulting individual elements as rigid bodies that undergo a planar or general spatial displacement we are able to apply the traditional kinematics theory to rapidly generate sets of potential solutions. The final design is then established via an FEA-augmented optimization sequence. Coupled with a virtual reality interface and a force-feedback device this approach provides the ability to quickly specify and evaluate multiple design problems in order to arrive at the desired solution.

Development of a Pressure Measuring Garment to Understand How to Quantify Compression

2020 ◽  
Author(s):  
Michael Weber ◽  
Abigail Clarke-Sather ◽  
Tara Bergeron ◽  
Anisa Janko ◽  
Alicia Jensen ◽  
...  
Keyword(s):  
General Trend ◽  
Autism Spectrum ◽  
The Body ◽  
Proof Of Concept ◽  
Compression Garment ◽  
Specific Location ◽  
Arm Circumference ◽  
Outcomes For Children ◽  
The Relationship ◽  
Measured Pressure

Abstract Encouraging research shows reductions in the number of disruptive behaviors for children diagnosed with Autism Spectrum Disorder (ASD) when wearing compression shirts. However, current studies do not consider the amount of pressure compression shirts apply to the body and how different amounts of pressure applied to the body may lead to different outcomes for children diagnosed with ASD. The purpose of this proof of concept research project was to develop a method for measuring the pressure applied by a compression shirt at a specific location on the body. This study used conductive thread as the principle element to measure the compression applied by a garment onto the body, specifically the arm. It was found that for the specific stitch and thread tested, the relationship between the displacement the sensor exhibits and the change in resistance was 25.95 Ω/m. With this relation, the pressure applied by a compression garment to a mannequin arm and the arms of four participants was found. A general trend that the measured pressure applied by a garment onto the body directly correlated with increasing individual arm circumference was found.

Sign in / Sign up

Export Citation Format

Share Document