Interstitial areas

The Iherzolitic shergottites are magnesian (Mg —70) olivine - clinopy roxene - chromite cumulates, dominated by coarse-grained poikilitic pigeonite enclosing rounded olivine (and chromite) crystals, with interstitial areas... 

Honeycomb Partial coalescence of nodules with softer interstitial areas produces a honeycomb-like effect... 

Pebble-cobble beaches consist of materials ranging in size from 2 to 256 mm. Some fine materials may be present in the interstitial areas between pebbles and there may also be large boulders in the area. Oil readily penetrates pebble-cobble beaches through the open spaces between the rocks. Retention of the oil may be low as it is often flushed out from the interstitial areas by natural tide or wave action. Oil will likely concentrate on the upper reaches, however, where there is little flushing action. As wave action constantly rearranges or reworks the sediments, few animals and plants are present, especially in the middle intertidal zone. Pebble-cobble beaches are not considered a sensitive beach type. 

Darcy Equation. The bulk resistance to flow of an incompressible fluid through a solid matrix, as compared to the resistance at and near the surfaces confining this solid matrix, was first measured by Darcy [23]. Since in his experiment the internal surface area (interstitial area) was many orders of magnitude larger than the area of the confining surfaces, the bulk shear stress resistance was dominant. 

Figure 5. A cross section through a Hz/ phase that illustrates that the interstitial areas (stipled) break the axial symmetry of the Hu tubes. The water cores (hatched) are in the center. A few lipids are shown in the leftmost cylinder for orientation. Lipid hydrocarbon chains fill the interstitial as well as the annular regions. Deviations from the mean hydrocarbon chain-segment density or in the mean extended length of the chains correspond to an entropically expensive set of chain configurations.

Support particle Nonpolar Interstitial area bonded phase (mobile phase)... 

Tissues or interstitial area—contains 25 percent of body fluids... 

A six compartments model representing the pharmacokinetics of dust movement within the alveolar area of the lungs and lymph nodes was proposed by Smith (1985) including free particles and two macrophage departments on the alveolar surfaces, temporary and encapsulation particles in the interstitial area, and particles in lymph nodes. Seven processes control the quantities of particles in each of the three areas ... 

Penetration of free particles through the alveolar membrane into the cells and interstitial area ... 

Sequestration of free particles or particles in macrophages in the interstitial area by fibrosis or other processes ... 

This is the process that controls the movement of water and small molecules in solution (electrolytes, nutrients) between the capillaries and the surrounding interstitial area. 

On the basis of these assignments and of his X-ray studies Sikka proposes that during fatigue weaker Van der Waal s and possibly some backbone bonds are broken. This has a twofold effect. The loosening of the structure permits on one hand the PS chains to locally rearrange themselves in a more perfect manner and to reduce the average intraphenyl and interchain distances. The local rearrangements are, on the other hand, accompanied by an increase in free volume in interstitial areas between the domains of improved order. 

The encephalopathy induced by lead toxicity is most hkely due to a compromise in the blood-brain barrier. Brain edema occurs in the interstitial area and appears due to compromised blood vessels integrity. The brain capillaries and blood vessels have endothelial cells that contain tight junctions and act as a seal or carrier that excludes many plasma proteins and organic molecules and impedes Na and K exchange. Elevated lead levels disrupt these vessels, and plasma proteins such as albumin enter the interstitial spaces, as do some ions. This increases osmotic pressure, and water accumulates in response. The increased interstitial fluid flows into the cerebrospinal fluid. The edema causes in an increase in intracranial pressure and restricts blood flow to the brain. The direct mechanisms by which the blood-brain barrier and blood vessels that compose the barrier may be compromised may be due to astrocytes appearing to be vulnerable to the toxic effects of lead. The astrocytes cover the walls of the brain blood vessels, and lead can injure these structures. 

With prolonged exposure to particulate matter at sufficiently high concentrations, the particulate matter continuously deposited in the alveolar spaces can trigger a sustained inflammatory reaction. The inflammation can alter particle clearance, initially increase the rate of clearance, and then later canse inhibition of clearance. This, in turn, intensifies the inflammatory reaction, which further impairs clearance and enhances the rate of particle accumulation in the alveolar region. Some of these particles are found in the interstitial areas and others in the alveolar spaces, where aggregates of macrophages, particles, and proteinaceous material may be observed. Adjacent epithelial cells become hypertrophic, hyperplastic, and occasionally, metaplastic. Freqnently, bronchiolar epithelium may appear to be extending down into the alveoli. This pattern of particle-indnced overload disease has been described in detail in rats chronically exposed to diesel exhaust or carbon black particles (39,40). The extent to which similar lesions are produced in humans exposed to similar levels of diesel soot or carbon black is not well understood. 

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