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Related to atactic: syndiotactic polymer


pertaining to or characterized by ataxia; marked by incoordination or irregularity.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


(a-tak'se-a, a?) [Gr. ataxia, lack of order]
Defective muscular coordination, esp. that manifested when voluntary muscular movements are attempted. atacticataxic (a-tak'tik, a?) (a-tak'sik, a?), adjective

alcoholic ataxia

In chronic alcoholism, ataxia due to a loss of proprioception.

bulbar ataxia

Ataxia due to a lesion in the medulla oblongata or pons.

cerebellar ataxia

Ataxia due to cerebellar disease.

choreic ataxia

Ataxia in patients with chorea.

Friedreich ataxia

See: Friedreich, Nikolaus

hysterical ataxia

Ataxia of leg muscles due to somatoform disorders.

limb ataxia

Inability to make smooth, coordinated movements of an arm or a leg, as when trying to touch an examiner's finger with an index finger or when trying to run one's right or left heel straight down the opposite shin. Limb ataxia is present when a limb that has no deficits in strength wobbles during movement or misses its target.

locomotor ataxia

Tabes dorsalis.

Marie ataxia

See: Marie, Pierre Marie

motor ataxia

Inability to perform coordinated muscle movements.

optic ataxia

Loss of hand-eye coordination in reaching for an object one has seen, due to damage to visually dedicated regions of the cerebral cortex.

sensory ataxia

Ataxia due to interference in conduction of sensory responses, esp. proprioceptive impulses from muscles. The condition becomes aggravated when the eyes are closed.
See: Romberg sign; spinal ataxia

spinal ataxia

Ataxia due to spinal cord disease.

static ataxia

Loss of deep sensibility, causing inability to preserve equilibrium in standing.
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
Mandal, "Photoluminescence in small isotactic, atactic and syndiotactic PVA polymer molecules in water," Chemical Physics, vol.
Four narrow molecular weight distribution grades of fully deuterated atactic PS (PSd8) were purchased from Polymer Source (Dorval, Quebec, Canada).
Atactic PP fibers and the polymer concrete composites were exposed at various gamma radiation doses using a [sup.60]Co source.
Mulhaupt, "Determination of plateau moduli and entanglement molecular weights of isotactic, syndiotactic and atactic polypropylenes synthesized with metallocene catalysts," Macromolecules 1998.
Intec, Wayne, NJ, which has been in business since 1980, is one of the country's leading manufacturers of modified roofing systems, both in torch-applied APP (atactic polypropylene) membranes and hot asphaltor cold-applied SBS (styrene butadiene styrene) membranes.
Polypropylenes (PP) synthesized using traditional Ziegler-Natta catalysts are generally about 95% isotactic, with a few percent atactic and some syndiotactic polymer.
Scientists have found this tendency can be overcome by adding atactic polypropylene (APP) or styrene butadiene styrene (SBS) to the asphalt mix.
studied the oxo-degradability of expanded atactic polystyrene (PS) that are formulated with cobalt and manganese based prooxidant additives [5].
The remainder of the material (if any) is atactic polymer.
Conversely, the diminution in the amount of the triads leads to a large amount of atactic insertion of the propylene monomer.
The new catalyst we have developed will broaden the molecular weight and produce resins with a fractional MFR, similar to what can be made with conventional Ziegler-Natta catalysts." Resins made with this catalyst have high purity, very little atactic content, low acidity, and low chloride levels.