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Showing 1 to 14 of 14 for “"body axes"”.
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Postembryonic Polarity Modification in the Acoel Convolutriloba longifissura
<p>Metazoans establish the bilateral body plan early in embryogenesis by patterning orthogonal body axes with polarity that is unaltered during the lifetime of most animals. While some organisms re-establish/modify body axes during regeneration and asexual reproduction, the acoel flatworm …
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Dynamics and Control of Flexible Aircraft
… and incorporates in a natural manner both rigid body motions of the aircraft as a whole and elastic deformations of the flexible components (fuselage, wing and empennage), as well as the aerodynamic, propulsion, gravity and control forces. The aircraft motion is described in terms of three …
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A study of aircraft agility
… fighter aircraft. The first model considers the body axes angular rates as control variables and is accordingly referred to as the body rate model. The second model is a rigid body model featuring rotational dynamics governed by the primary control surface deflections. The body rate model is …
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Investigating the underlying mechanisms of axis formation in Drosophila melanogaster
The establishment of the body axes has been well-studied in Drosophila melanogaster, and is known to occur prior to fertilisation in the developing egg chamber as a result of crosstalk between the germline and the surrounding somatic epithelium. Whilst it is known that the formation of the …
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Control power requirements for the velocity vector roll
… control moments about the three principal body axes. These equations take on a form well suited for numerical optimization methods. The Schittkowski sap optimization code is used to provide fast, accurate solutions. The numerical method also shows the advantage of being adaptable to …
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Transcriptional Integration of Wnt and Nodal Signals in the Establishment of the Spemann Organizer
Establishment of the vertebrate body axis requires the formation of the organizer domain during early embryogenesis. In amphibians, this domain is referred to as the Spemann Organizer and is essential for germ layer patterning and formation of the embryonic body axes. The Wnt and Nodal signaling …
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Analysis of HOXA5 expression and function in development of the central nervous system
… spatio-temporal patterning of the vertebrate body axes. In mouse, Hoxa5 transcripts are differentially expressed in specific mesoderm-derived structures and in the most anterior domain of expression in the central nervous system (CNS). However, the functional significance of any pattern of …
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Ancient origins of the chordate forebrain: Conserved patterning of the anterior neuroectoderm in amphioxus
… origin of this key aspect of the chordate body plan remains obscure. In recent years, a conserved anterior gene regulatory network (aGRN) has been shown to pattern the larval anterior nervous system of several invertebrates, including the two non-chordate deuterostome phyla (echinoderms and …
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Spontaneous directional preferences in taxonomically and ecologically distinct organisms: examining cues and underlying mechanisms
… (Cambarus sciotensis) spontaneously align their body axes relative to the magnetic field. In snapping turtles, this response is sensitive to low-level radio frequency fields, consistent with a mechanism involving a light-dependent radical pair mechanism. Findings from the turtle experiments also …
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Redefining the Gastrula Organiser in Early Chick Embryo Development
… responsible for patterning the primary body axes and inducing the formation of the embryonic nervous system. Hensen’s node was identified as the equivalent structure in birds due to its ability to induce a complete secondary axis with a regionalised neural tube when grafted to an ectopic …
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Der Einfluss von Retinsäure auf die dorsoventrale Augenachse des Haushuhns
… vertebrates, especially in the polarization of body axes. It has been proposed to be a determining factor in setting up the dorsoventral polarity of the eye axis, thereby organizing the later developing retinotopic visual projection. The pathfinding of retinal axons along the dorsoventral axis …
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Illuminating the Black Box: Defining and Modeling Peri-Implantation Human Embryogenesis
… implants into the maternal uterus and specifies body axes in preparation for gastrulation. It is thought that most pregnancies fail during the two-week period between fertilization and gastrulation. However, the inaccessibility of human embryos during implantation has limited our understanding of …
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Variabilität molekularer axialer Differenzierung am Beginn der Gastrulation beim Kaninchen
Hintergrund der vorliegenden Arbeit sind molekulare Mechanismen, die an der Differenzierung der Körperachsen in der frühen Gastrulationsphase des Säugerembryos beteiligt sind. Variabilität und Stabilität der molekularen Blaupause , die der morphologischen Entwicklung zu Grunde liegt, wurden …
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Astrocytic Sonic Hedgehog signalling in development and disease
… tissue patterning, and the establishment of body axes (Rowitch et al., 1999; Echelard et al., 1993; Ericson et al., 1997; Jessel and Lumsden, 1997). Beyond these canonical roles, recent research has revealed a broader spectrum of Shh functions, encompassing both pre- and post-natal processes …