annulus

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annulus

 [an´u-lus] (pl. an´nuli) (L.)
alternate spelling of anulus.

annulus

/an·nu·lus/ (an´u-lus) pl. an´nuli   [L.] anulus.

annulus

(ăn′yə-ləs)
n. pl. annu·luses or annu·li (-lī′)
1. A ringlike figure, part, structure, or marking, such as a growth ring on the scale of a fish.
2.
a. A ring or group of thick-walled cells around the sporangia of many ferns that functions in spore release.
b. The ringlike remains of a broken partial veil, found around the stipes of certain mushrooms.

annulus

annulus

Any ring-like structure (e.g., mitral valve annulus).

annulus

Any ring-like structure.

annulus

  1. the ring of cells in the moss or fern capsule which splits to allow the liberation of spores.
  2. a ring of tissue surrounding the stalk in the fruiting bodies of the BASIDIOMYCOTA fungi.

annulus, anulus

pl. annuli, anuli [L.] a small ring or encircling structure.

atrioventricular annulus
a ring of Purkinje cells around the right A-V orifice that serves the myocardium and valves locally and also serves as an alternative connection between the atria and the ventricles.
fibrocartilaginous annulus
the circular pad which connects the tympanic membrane to the external acoustic meatus.
annuli fibrosi
1. four fibrous rings at the base of the heart to which the myocardium is attached, one around each A-V orifice and one each around the aorta and the pulmonary artery.
2. the intervertebral disks consist of a soft central pulpy nucleus and a peripheral annulus fibrosus.
annulus iridis
the iris consists of two rings, an inner smooth annulus iridus minoris, and an outer plicated part, the annulus iridis major.
annulus preputialis
the ring of skin marking the entrance to the cavity of the prepuce.
annulus sclerae
a roll of connective tissue on the inside of the sclera at the corneoscleral junction.
spermatic annulus
a small ring condenses around the proximal centriole of the spermatid.
annulus vaginalis
the ring through which the peritoneal cavity connects with the cavity of the vaginal tunic.
References in periodicals archive ?
If you would like to have your deer or other game species accurately aged using the cementum annuli method, contact the Wildlife Analytical Laboratory at (512) 756-1989, or visit them online at deerage.
and process errors associated with estimating th e number of worn annuli all combine to produce the low precision in age estimates and therefore growth parameters (Tribuzio et al.
If the smoothed edge analysis and marginal increment data plotted by day of year formed sinusoidal cycles with a frequency of 1 y (a qualitative, not model-based result), the assumption of true annuli was considered validated and the timing of annulus formation was estimated.
Left and right otoliths were examined side by side to aid in discerning between annuli and checks.
When the aggregate power from the L annuli is considered the CF is written as follows:
Therefore, our objectives were to compare 2 commonly used aging techniques for Cougars, including gum-line measurements (Laundre and others 2000) and cementum annuli analysis (Schroeder and Robb 2005), and to discuss potential issues related to error and disagreement between these techniques.
The situation is very different at ports 2 and 3, however, where the annuli individually harbor more aesthetascs (4-5 per annulus), and because the annuli are smaller, where more individual aesthetascs might be exposed to stimulus escape from the local port.
Annuli fibrosi of A1, B1 and C1 showed disorgani- zed lamellar pattern cystic cavities and cleft formation and decreased amount and pairing of disc cells.
Annuli were defined by patterns of crowding and crossing over of circuli (Carlander, 1969).
Using the expressions for volumetric flow-rate in a concentric annuli developed by Bird et al.
Laminar flows of Bingham plastic and power law fluids in concentric annuli have been analyzed by Fredrickson and Bird (1958) while laminar flow of Herschel-Bulkley fluids in concentric annuli has been investigated by Hanks (1979) who provided a non-analytical solution, although with some errors (Buchtelova, 1988), together with several tables covering various annulus aspect ratios.