Aging effect permeability

Guo, J.-H. Robertson, R.E. Amidon, G.L. Influence of physical aging on mechanical properties of polymer free films the prediction of long-term aging effects on the water permeability and dissolution rate of polymer film-coated tablets. Pharm. Res. 1991, 8 (12), 1500-1504. 

Fig. 35. Oxygen permeability decay through BPA—BnzDCA films illustrating physical aging effects for the following film thicknesses o, 33 p,m , 28 p,m O, 9.7 / m A, 4.4 jiim V, 1.85 Atm . , 0.99 Atm , 0.74 Atm , 0.58 Atm A, 0.25 Atm. Reprinted from Ref 131 with permission from Elsevier..

Gorodeski GI [2005] Aging and estrogen effects on transcervical—transvaginal epithelial permeability. J Clin Endocrinol Metab 90 345-351... 

Ceramide is now included in some skin creams which are claimed to be beneficial to the skin, preventing drying and reducing the effects of ageing. Linoleoyl-ceramide is present in the skin where it restricts water permeability, preventing excessive water loss from the skin. 

The method of placement makes shoterete potentially more variable and more anisotropic than normal concrete. Consequently, the development of the physical and mechanical properties such as strength, shrinkage, permeability and durability is drastically different from those of normal concrete. The effects are particularly noticeable during the very early and later ages [107, 109, 117]. 

Mechanism of Action-. A selective vascular endothelial growth factor (VEGF) antagonize that selectively binds and activates receptors located on the surface of vascular endothelial cells. Therapeutic Effect Blocks angiogenesis and vascular permeability and inflammation which contribute to the progression of the neovascular (wet) form of age-related macular degeneration (AMD). 

Depending on the susceptibility of the raw material to aging, physical, chemical, and/or microbiological stability should be assessed. This is especially true for liquid or semisolid ingredients, in which interaction with the container or permeability of the container to air and moisture could have a detrimental effect on the raw material. 

Olsen, T.W., et al. 1995. Human scleral permeability. Effects of age, cryotherapy, transscleral diode laser, and surgical thinning. Invest Ophthalmol Vis Sci 36 1893. 

Anthony, D.C., et al. 1997. Age-related effects of interleukin-p on polmorphonuclear neutrophil-dependent increases in blood-brain barrier permeability in rats. Brain 120 435. 

For concrete at early ages the most important is the effect of chemical processes on its transport and strength properties, e.g. porosity n=f(Thydr)> intrinsic permeability T=f(Thydr,d), and mass source related to the hydration tn-hydr = f (Thydr) Creep of concrete is modeled by means of the solidification theory [17], where the degree of cement hydration Thy dr is used as the volume fraction of the load-bearing portion of hydrated cement. 

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