Damage progression

By examining the dispersion properties of surface acoustic waves, the layer thickness and mechanical properties of layered solids can be obtained using the SAM. It can be used to analyze the wear damage progress [104], and detect the defects of thermally sprayed coatings [105]. 

Progression factors hasten decline in kidney function after initiation of kidney damage. Progression factors include glycemia in diabetics, hypertension, proteinuria, and smoking. 

M.F. Horstemeyer et al Numerical, experimental, nondestructive, and image analyses of damage progression in cast A356 aluminum notch tensile bars. Theor. App. Fracture Mech. 

Within a certain degree of hepatocellular damage, liver cell functions remain completely or widely intact at least, no impaired partial functions are yet detectable under clinical conditions. As liver damage progresses, however, numerous cellular functions become increasingly affected, so that clinically relevant disorders become evident. Thus impairment of the hepatic excretory capacity can be taken as a criterion of parenchymal damage. 

As renal tubular damage progresses the concentration of serum creatinine increases. One of the most severe cases in the Cd-polluted Kakehashi River basin had a serum creatinine value of 4.4 mg/100 ml. Progression to renal failure was evidenced by high blood nitrogen, severe anemia, acidosis, hyponatremia, hyperphosphatemia and hypocalcemia [81]. It was reported that four out of six itai-itai disease patients died of uremia [82]. 

The ability of the renal cells to make 1.25 dihydroxycholecalciferol fulls as the renal tubular damage progresses. Calcium absorption is reduced and there is a tendency towards hypocalcaemia. Parathyroid hormone is stimulated in an attempt to restore plasma ealcium to normal, and high circulating PTH may have adverse effects on bone if this is allowed to continue (Fig. 2). Secondary hyperparathyroidism causes the changes in bone which are characteristic of renal osteodystrophy. 

In the earlier stages of tissue damage, cytoplasmic enzymes may leak from cells when membrane permeability has altered (Keil 1990). As the severity of tissue damage progresses, enzymes normally present in subcellular organelles will he released into the circulation (Schmidt and Schmidt 1987 Bouma and Smit 1988). The molecular mass of the enzyme also governs its cellular and renal clearances. There are considerable variations in the published data for plasma half-lives (or clearance rates from plasma), and these variations are partly due to the different methodologies used for these measurements and the lack of suitable enzyme preparations. 

Weigmann, H.D. Analysis and quantification of hair damage. Progress Report No. 2.TRI Princeton, Princeton, NJ (1991). 

Takemura K, Fujii T. Fatigue strength and damage progression in a circular-holenotched GRP composite under combined tension/torsion loading. Compos Sci Technol 1994 52 519-26. 

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