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Related to Branchial arches: Branchial cyst, branchial fistula

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Autoregressive Conditional Heteroskedasticity

A statistical measure of the average error between a best fit line and actual data that uses past data to predict future performance. General Autoaggressive Conditional Heteroskedasticity is the most common way of doing this. See also: Fractal Distribution.
References in periodicals archive ?
Hemifacial microsomia in pediatric patients: asymmetric abnormal development of the first and second branchial arches.
Fish were anesthetized with MS-222, and the tissue supporting all lateral and medial rakers and microbranchiospines was removed with microforceps from the anterior four branchial arches on both sides of five fish (Smith and Sanderson, 2007).
Anomalies of the first, second, and third branchial arches have been commonly described.
5) It consists of (5) paired branchial arches & each separated externally by ectodermal clefts and internally by endodermal pouches.
3,4) In 1997, Vieille-Grosjean et al showed for the first time that at 4 weeks of development, human branchial arches express the paralogous groups using the mouse homologues of HOXB1, HOXA2, HOXB2, HOXA3, HOXB3, HOXD3, HOXB4, and HOXC4 as probes for in situ hybridization.
The cartilaginous structures of the larynx are derived from the fourth and sixth pairs of branchial arches and begin their development in the fifth week of gestation.
By the sixth week of intrauterine development, the embryo exhibits paired branchial arches.
By the end of the 4th week of embryonic life, the branchial arches (derived from neural crest cells) and the mesenchyme (derived from the lateral mesoderm) are easily recognizable.
5) They are thought to arise from unsegmented mesoderm in the branchial arches.
Congenital type is due to entrapment of ectodermal substance between the midline fusion of first and second branchial arches during third and fourth intrauterine life.
It appears' to occur as a result of a failure of fusion of the paired second branchial arches in the midline during embryogenesis.