Osmotic resistance

Rgure 4.7. Evolution of the osmotic resistance H normalized by >w/ for PDMS-in-water emulsions. The dashed line is a visual guide. The solid line corresponds to the best fit of the normalized data obtained by Mason et al. [7]. (Adapted from [31].)... 

A set of experiments was performed at variable droplet sizes. The graph in Fig. 4.7 shows the dependence of the normalized (by Kint/a) osmotic resistance as a function of the oil volume fraction. The normalized values fall onto a single curve within reasonable experimental uncertainty. The results were compared to the normalized data obtained by Mason et al. [7] in the presence of surfactants. These latter are represented as a solid line that corresponds to the best fit to the experimental points (Eq. (4.18)). It is worth noting that the normalized pressures in solid-stabilized emulsions are much larger than the ones obtained in the presence of surfactants. 

As reported in this chapter, the microscopic origin of both compressibility and elasticity of dense emulsions is rather well understood. Emulsions have elastic properties arising from either surface tension or surface elasticity and plasticity. Some protein-stabilized emulsions obey the same phenomenology as solid-stabilized emulsions they exhibit substantially higher osmotic resistances and higher shear moduli than surfactant-stabilized emulsions [38 0]. Moreover, they are strongly resistant to water evaporation. Proteins possess the ability to form... 

C6Hs)3PCH2Si(OCH2CH2)3N]+I produces a stabilizing effect on erythrocyte membranes at concentrations of 1 7/ml. The zone of the minimum osmotic resistance of erythrocytes is 0.46% of the NaCl concentration and the zone of the maximum osmotic resistance is 0.38%, thus exceeding the control values57). 

Isotetrandrine Effect on osmotic resistance of human erythrocyte membrane 365... 

Osmotic resistance of erythrocytes was studied by the method of HCl-hemolysis [10],... 

Changes in the erythrocytes osmotic resistance were not observed. Adsorption of total plasma proteins on modified MC was lower than 12 %, but it was about 60 - 70 % on unmodified particles. Table 6 summarizes the results obtained of MC sorption efficiency to substances of different molecular mass in donor plasma. The sorption mechanism of low and middle molecular weight substances (phenobarbital and cyanocobalamin) on iron-carbon and restored-iron MC is apparently connected with absorption of molecules into the sorbent s pores. Iron-carbon composites have a more porous structure than restored-iron, therefore the... 

Recently, it was suggested [191] to control the depth of functionalization of the beads in order to reduce the diffusion path within a bead and facilitate the ion exchange and r eneration processes. The core of the so-caUed shaUow-sheU resins has no functional sites at all. Such cation exchangers exhibit improved osmotic resistance and good mechanical strength, their regeneration proceeds faster and the consumption of regenerants is smaller. 

The shape and fragility of red cell membranes are greatly influenced by their free cholesterol content, and bile salts have been shown to affect the free cholesterol content of red cell membranes in at least two ways (79). Serum cholesterol transesterase activity is inhibited by bile salts, and thus removal of free cholesterol from the membrane, which is facilitated by esterification, is delayed. Bile salts induce a shift in the cell/serum free cholesterol partition ratio in favor of the cell, so that supranormal concentrations of cholesterol occur in the cells. Such cells are flat and osmotically resistant and appear as target cells on stained smears. Patients with jaundice, especially obstructive jaundice, have numerous target cells, and it has been postulated that increased concentrations of bile salts in the serum of such patients may account for the target cell formation (79). 

Figure VII - IS. Effectiveness of pressure increase as a function of the ratio between the osmotic resistance and the membrane resistance.

Leiken and Eng (1963), in a typical study, reported that three of seven Pb-poisoned children showed evidence of shortened erythrocyte survival. Hemberg et al. (1967) employed H -labeled difluorophosphonate and Berk et al. (1970) used C " -labeled glucose to demonstrate reduced erythrocyte survival via tracer kinetics. Earlier studies also documented that cell survival is impaired through the joint operation of increased erythrocyte fragility and increased osmotic resistance of cell membranes. A commonly accepted... 

Altered cell fragility and osmotic resistance. Hemolytic anemia from cell destruction. 

A normocytic or microcytic, hypochromic anemia is most frequently observed, but macrocytosis has been seen in the final stages of GD (Feinberg and Quigley 1946, Reich et al. 1951). The life span of the red cells has been found shortened in the few cases so examined (Motulsky et al. 1958). Usually osmotic resistance is normal (Pick 1933, Burger 1934), but a hemolytic component with increased red cell fragility may exist (Sobel and Kaye 1942). Hemoglobinuria was observed in... 

The acanthocytes are of normal size. Osmotic resistance is usually decreased, while mechanical resistance is increased. Hemoglobin concentration is normal or sHghtly decreased an atypical hemoglobin has not been found. Mild anemia was seen in some patients. Upon incubation at 37 and 4 C for 48 hours hemolysis is increased in the presence of acanthocytosis (Ways and Simon 1964). 

According to the osmotic-resistance nitration model, the formation of a foulant layer on the membrane surface may affect permeate flux in two different ways ... 

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