Distribution of calcium

A), distribution of calcium ( Ca) and (B), potassium ( K) in the mature zone of flax hypocotyl constituted of cells which had stopped their elongation. (C), distribution of calcium in young flax hypocotyl constituted of elongating cells. (D), small areas of calcium accumulation in the aisles of the intercellular spaces. 

To determine how controlled manipulation of digestion conditions influences the distribution of calcium among possible ligands from a food or meal. 

Bulk liquids from the self-chosen diets of the volunteers in HS-II and HS-III have not been analyzed, however, milk was included with the 2nd plate food composites. Table IV is a summary of the distribution of calcium in the self-chosen food composites. Final... 

Table IV. Distribution of Calcium Content of Self-Chosen Diet Composites...

Hoskins B, Ho IK. 1982. Chlordecone-induced alterations in content and subcellular distribution of calcium in mouse brain. J Toxicol Environ Health 9 535-544. 

Calcium is the major mineral component of bone and normal repair and remodelling of bone is reliant on an adequate supply of this mineral. Calcium uptake in the gut, loss through the kidneys and turnover within the body are controlled by hormones, notably PTH and 1,25 dihydroxy cholecalciferol (1,25 DHCC or 1,25 dihydroxy vitamin D3 or calcitriol). Refer to Figure 8.12 for a summary of the involvement of PTH and vitamin D3 in controlling plasma calcium concentration. These two major hormones have complementary actions to raise plasma calcium concentration by promoting uptake in the gut, reabsorption in the nephron and bone resorption. Other hormones such as thyroxine, sex steroids and glucocorticoids (e.g. cortisol) influence the distribution of calcium. 

In the preceding sections, we have discussed the marine processes that control calcium carbonate s formation, dissolution, and delivery to the seafloor. Their combined effects determine the geographic distribution of calcium carbonate in marine sediments seen in Figure 15.5. As noted earlier, the global distribution of calcareous sediments does not seem to follow that of plankton production. This points to the overriding importance of the processes that control the dissolution and sedimentation of calcium carbonate. 

Parameters influencing the distribution of calcium carbonate with increasing water depth in equatorial Pacific sediment. Note that fi is reported as a percentage (%). Source From van Andel, Tj. H., et al. (1975). Cenozoic History and Paleoceanography of the Central Equatorial Pacific Ocean, Geological Society of America, Boulder, CO, p. 40. 

Mecfianism of Action A cinchona alkaloid that relaxes skeletal muscle by increasing the refractory period, decreasing excitability of motor end plates (curare-like), and affecting distribution of calcium with muscle fiber. Antimalaria Depresses oxygen uptake, carbohydrate metabolism, elevates pH in intracellular organelles of parasites. Therapeutic Effect Relaxes skeletal muscle produces parasite death. Pharmacokinetics Rapidly absorbed mainly from upper small intestine. Protein binding 70%-95%. Metabolized in liver. Excreted in feces, saliva, and urine. Half-life 8-14 hr (adults), 6-12 hr (children). 

Hsu, Peng-Cheng and W. H. Adolph, The distribution of calcium in leafy... 

The fairly wide distribution of calcium phosphates in complex solutions containing typical dissolved constituents in equilibrium bottom ash leachates can be explored using thermodynamic modeling. Such calculations are useful to discern the role of solution phase complexation of the major cations, typically via OH , CF, SO , HCOJ, and COi . 

Figure 5.11 Effect of pH on the distribution of calcium ( ), inorganic phosphorus (O), magnesium (O) and citrate (A) between the colloidal and soluble phases in bovine milk.

Hohman, W., Schraer, H. The intracellular distribution of calcium in the mucosa of the avian shell gland. J. Cell. Biol. 30, 317 (1966)... 

The uptake of Ca2+ by sporulating cells is of interest as it involves the reversal of the normal distribution of calcium between the intracellular compartment and the external medium. It is not... 

The distribution of calcium carbonate in sediments with ocean depth shows wide variations. In open ocean basins, where rates of detrital sedimentation are moderate to low, sediments above 3000 meters water depth are generally high in calcium carbonate, whereas sediments below 6000 meters generally have very low calcium carbonate content. Between these depths there is a poor correlation between the weight % calcium carbonate and depth (Smith et al., 1968). Turekian... 

Biscaye P.E., Kolia V. and Turekian K.K. (1976) Distribution of calcium carbonate in surface sediments of the Atlantic Ocean. J. Geophys. Res. 81, 2595-2603. 

Calcium Content of Starch Isolated from Lime-Treated Corn. Starch is the major component of the corn grain and derived products (see Table VII). To explore in more detail the distribution of calcium after the nixtamalization process, calcium was measured in starch isolated from untreated and lime-treated com. These analyses (see Table VIII) indicated that calcium was fixed or bound in some way to the starch. There was approximately 2.9 times more calcium in starches isolated from lime-treated corns than in starches isolated from untreated grains. Figure 7 shows micrographs of isolated starches. 

Calcium chloride is both hygroscopic and deliquescent. Thus, solid material will absorb moisture from the air or snow and ice until it dissolves, and the solution will continue to absorb moisture until an equilibrium is reached between the vapor pressure of the solution and that of the air. At 95 percent relative humidity, one pound of anhydrous calcium chloride will absorb 17.3 lb of water. The ability of calcium chloride to absorb moisture makes it useful in many construction, commercial, and industrial applications. Table 26.13 gives the market distribution of calcium chloride.47 U.S. demand for calcium chloride in 2000 was 1.3 million tons. 

Walaas SI, Nairn AC, Greengard P (1983b) Regional distribution of calcium- and cyclic adenosine 3 5 -monophosphate-regulated protein phosphorylation systems in mammalian brain. II. Soluble systems. J Neurosci 3 302-311. 

McRitchie DA, Hardman CD, Halliday GM (1996) Cytoarchitectural distribution of calcium binding proteins in midbrain dopaminergic regions of rats and humans. J Comp Neurol 364 121-150. 

Figure 3. General distribution of calcium carbonate with increasing water depth in deep ocean basins (after Ref. 9)...

The Distribution of Calcium Carbonate Saturation States and Their Relation to Sediment Marker Levels... 

NWA Oil is basaltic in composition, with enrichments in aluminum, calcium, and titanium relative to chondrites, and is ferroan, with an mg of 36. NWA 011 has a cumulate-eucrite-like REE pattern (Figure 6). However, Afanasiev et al. (2000) report that NWA Oil has a negative europium anomaly and samarium content of 13.3 X Cl, more like those expected for a mafic melt composition. Yamaguchi et al. (2002) suggest that the heterogeneous distribution of calcium phosphate is the likely explanation for this discrepancy. This is supported by their hafnium and tantalum analyses, which are at 12.8 X Cl and... 

Archer D. E. (1996a) An atlas of the distribution of calcium carbonate in sediments of the deep sea. Global Biogeochem. 

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