shear stress

(redirected from Tangential stress)
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Related to Tangential stress: Radial stress

shear stress

the force acting in shear flow expressed per unit area; units in the CGS system: dynes/cm2.
Farlex Partner Medical Dictionary © Farlex 2012

shear stress

A frictional force tangential to the direction of a flowing fluid, the force of which is directly related to the fluid’s viscosity shear stress. In blood vessels, shear stress acts on endothelium and is the mechanical force responsible for the acute changes in luminal diameter. 

Stress parallel to a given surface (e.g., a fault plane) that results from forces applied parallel to the surface or from remote forces transmitted through surrounding rock.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


(stres) [Fr. estresse, narrowness]
1. Any physical, physiological, or psychological force that disturbs equilibrium
2. The consequences of forces that disturb equilibrium.
3. Force applied per unit area. In the physical sciences, stresses include forces that deform or damage materials, such as impact, shear, torsion, compression, and tension. These physical stresses are particularly important in certain branches of health care, e.g., dentistry or orthopedic surgery, and in biotechnology industries, e.g., in the design and use of prostheses, grafts, and perfusion pumps.

Physiological stresses include agents that upset homeostasis, such as infection, injury, disease, internal organ pressures, or psychic strain.

In psychology, stresses include perceptions, emotions, anxieties, and interpersonal, social, or economic events that are considered threatening to one's physical health, personal safety, or well-being. Marital discord; conflicts with others; battle, torture, or abuse; bankruptcy; incarceration; health care crises; and self-doubt are all examples of conditions that increase psychic stresses. The response of an organism or material to stress is known as adaptation. See: adaptation; anxiety; fracture; homeostasis; Laplace, law of; relaxation response

critical incident stress

One's emotional reaction to a catastrophic event such as a mass casualty incident or the death of a patient or coworker. Often such events negatively affect the well-being of health care providers.

oxidative stress

The cellular damage caused by oxygen-derived free radical formation. The three most important are superoxide (O2-), hydrogen peroxide (H2O2), and hydroxyl ions; these are produced during normal metabolic processes as well as in reaction to cell injury. The extent of their damaging potential can be decreased by antioxidants.
See: antioxidant; free radical; superoxide; superoxide dismutase

prenatal stress

Anxiety, tension, depression, or other psychological discomfort experienced by a pregnant woman.

shear stress

Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
For single-cycle pipe freezing, Figures 6(a) and 6(b) show the tangential stress [[sigma].sup.*.sub.[theta]] and radial displacement [u.sup.*] , respectively, along the inner edge of the inhomogeneous frozen wall as a function of the nonuniform coefficient of ground press [lambda] and of the excavation unloading ratio [eta].
As can be seen in Figures 6 and 7, radial and tangential stresses decrease linearly along the radial direction.
The difference in the shear stress of the interlayer at the interfaces and the tangential stress jump is smaller when the residual surface tension amplitude is smaller.
Caption: FIGURE 7: Tangential stress field per unit twist [[tau].sup.2]/[alpha]; a = 2, b = 1; [k.sub.1] = [k.sub.3] = 1, [k.sub.2] = 2.
As the inverse simulations were performed based on the forward solution of tangential stress field, the reconstructed temperature fields do not match with the direct temperature field.
We can assume that the tangential stress and normal stresses from deformation along the other axes are missing: [[sigma].sub.y] = [[sigma].sub.z] = [[tau].sub.xy] = [[tau].sub.xz] = [[tau].sub.yz] = 0.
When the tangential stress [[sigma].sub.3] in the tensile state is selected as the judgment standard of the pressure arch, the lateral pressure coefficient is [xi] = 0.2, and the pressure arch line is shown in Figure 10.
The motion of a fluid can be obtained as a result of several effects such as various types of motion of the boundaries, application of a body force, wall that applies a tangential stress on the fluid or application of a pressure gradient.
Hydra-Cell diaphragm pumps from WANNER INTERNATIONAL are claimed to impose only low levels of tangential stress on the pumped fluid making them ideal for pumping a wide range of shear sensitive materials.
The stresses can be high, especially the tangential stress if the contact is not lubricated.
Figures 5 and 6 show the variations of the radial stress [[sigma].sub.rr] and tangential stress [[sigma].sub.[phi][phi]] with respect to the radius r, respectively.