195:
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537:, the interruption of sensory nerve fibers, and functional instability, then a subject's postural sway should be altered. Joint stability can be enhanced by the use of an external support system, like a brace, to alter body mechanics. The mechanical support provided by a brace provides cutaneous afferent feedback in maintaining postural control and increasing stability.
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The most common residual disability after any sprain in the body is instability. Mechanical instability includes insufficient stabilizing structures and mobility that exceed the physiological limits. Functional instability involves recurrent sprains or a feeling of giving way of the injured joint.
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cause changes in the density that reinforce the original perturbation. Such instabilities usually require that the motions of stars be highly correlated, so that the perturbation is not "smeared out" by random motions. After the instability has run its course, the system is typically "hotter" (the
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deficits and impaired postural control in the joint. Individuals with muscular weakness, occult instability, and decreased postural control are more susceptible to injury than those with better postural control. Instability leads to an increase in postural sway, the measurement of the time and
533:. The measurement of a subject's postural sway can be calculated through testing center of pressure (CoP), which is defined as the vertical projection of center of mass on the ground. Investigators have theorized that if injuries to joints cause
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having either real part greater than zero, or, for the eigenvalues on the imaginary axis, the algebraic multiplicity being larger than the geometric multiplicity. The equivalent condition in
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instabilities can be divided into two general groups (1) hydrodynamic instabilities (2) kinetic instabilities. Plasma instabilities are also categorised into different modes – see
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in a system is said to be unstable if it evolves without bounds. A system itself is said to be unstable if at least one of its state variables is unstable.
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756:"Postural Corrections after Standardised Perturbations of Single Limb Stance: Effect of Training and Orthotic Devices in Patients with Ankle Instability"
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is that at least one of the eigenvalues is greater than 1 in absolute value, or that two or more eigenvalues are equal and of unit absolute value.
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75:, a structural beam or column can become unstable when excessive compressive load is applied. Beyond a certain threshold, structural
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Roupas, Zacharias (January 2019), "The
Gravothermal Instability at All Scales: From Turnaround Radius to Supernovae",
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motions are more random) or rounder than before. Instabilities in stellar systems include:
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greater than zero (or if zero is a repeated root). This is equivalent to any of the
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Characterized by some of the outputs or internal states growing without bounds
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Unstable flow structure generated from the collision of two impinging jets.
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715:"Effect of Orthotics on Postural Sway Following Inversion Ankle Sprain"
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increase with time, without bounds. Not all systems that are not
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83:, which in turn increases deflections. This can take the form of
246:(some analogy to the Rayleigh–Taylor instability); found in the
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606:"Parallel AMR Code for Compressible MHD or HD Equations"
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A ball on the top of a hill is an unstable situation.
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87:or crippling. The general field of study is called
182:Biot instability (surface wrinkling in elastomers)
754:Pintsaar, A.; Brynhildsen, J.; Tropp, H. (1996).
719:Journal of Orthopedic and Sports Physical Therapy
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608:. Los Alamos National Laboratory. Archived from
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479:can be unstable, if small perturbations in the
30:"Unstable" redirects here. For other uses, see
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529:distance a subject spends away from an ideal
713:Guskiewicz, K. M.; Perrin, David H. (1996).
514:Various instabilities in cold rotating disks
453:Plasma stability § Plasma instabilities
430:(similar to the Rayleigh–Taylor instability)
424:(similar to the Rayleigh–Taylor instability)
52:means that some of the outputs or internal
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23:. For the political science concept, see
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580:"Definition of BAROCLINIC INSTABILITY"
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19:For inherently unstable aircraft, see
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373:convective instability of the first
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761:British Journal of Sports Medicine
462:this paragraph in plasma stability
60:are unstable; systems can also be
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404:(similar, but different from the
357:conditional-symmetric instability
179:of a nonlinear constitutive model
809:eFluids Fluid Flow Image Gallery
468:Instabilities of stellar systems
288:convective symmetric instability
239:. Fluid instabilities include:
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161:Instability in solid mechanics
105:Instability in control systems
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422:Plateau-Rayleigh instability
402:Kelvin–Helmholtz instability
97:is a major component of all
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555:"Definition of INSTABILITY"
412:Rayleigh–Taylor instability
353:nonlocal static instability
203:Rayleigh–Taylor instability
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417:Saffman–Taylor instability
331:atmospheric thermodynamics
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635:The Astrophysical Journal
491:of rapidly rotating disks
440:Benjamin-Feir Instability
327:thermodynamic instability
32:Unstable (disambiguation)
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510:Radial-orbit instability
505:Gravothermal instability
398:Drift mirror instability
258:Hydrodynamic instability
700:10.3390/universe5010012
584:www.merriam-webster.com
559:www.merriam-webster.com
481:gravitational potential
311:Hydrostatic instability
253:Atmospheric instability
219:instabilities occur in
185:Baroclinic instability
139:characteristic equation
95:Atmospheric instability
385:mechanical instability
304:rotational instability
292:barotropic instability
276:baroclinic instability
244:Ballooning instability
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73:structural engineering
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774:10.1136/bjsm.30.2.151
604:Shengtai Li; Hui Li.
406:diocotron instability
284:conditional symmetric
280:symmetric instability
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500:Firehose instability
447:Plasma instabilities
319:vertical instability
300:shearing instability
272:Inertial instability
266:atmospheric dynamics
237:magnetohydrodynamics
89:structural stability
691:2019Univ....5...12R
647:1994ApJ...425..551M
519:Joint instabilities
369:thermal instability
345:buoyant instability
262:dynamic instability
190:Fluid instabilities
172:Elastic instability
531:center of pressure
394:BĂ©nard instability
349:latent instability
341:static instability
323:parcel instability
315:static instability
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201:simulation of the
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495:Jeans instability
177:Drucker stability
117:dynamical systems
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631:Merritt, D.
436:Instability
408:in plasmas)
377:second kind
337:Conditional
147:eigenvalues
77:deflections
66:limit cycle
64:or exhibit
50:instability
818:Categories
682:1809.07568
616:2006-05-31
434:Shock Wave
361:convective
109:See also:
101:on Earth.
68:behavior.
675:(1): 12,
365:potential
296:Helmholtz
143:real part
669:Universe
589:23 April
564:23 April
473:Galaxies
381:absolute
167:Buckling
85:buckling
81:stresses
79:magnify
792:8799602
783:1332381
741:8728531
687:Bibcode
643:Bibcode
229:plasmas
221:liquids
149:of the
137:of its
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458:Plasma
58:stable
54:states
677:arXiv
541:Notes
367:, or
225:gases
217:Fluid
135:roots
788:PMID
737:PMID
591:2018
566:2018
475:and
375:and
235:and
227:and
141:has
119:, a
778:PMC
770:doi
727:doi
695:doi
651:doi
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383:or
339:or
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313:or
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260:or
126:In
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