Aqueous lining layer

The existence of osmiophilic material in various forms in the aqueous lining layer has been previously reported (34,35,41,45,47,48). The appearance of osmiophilic material at the air-liquid interface in the form of a film covering the aqueous lining layer is of special interest for the retention of particles and will be discussed later in further detail. 

Figure 1 Transmission electron mierograph of normal horse trachea after osmium te-troxide-perfluorocarbon fixation The air-liquid interface is eovered by an osmiophilic film (arrow). The aqueous lining layer surrounds and covers the eilia. GC, goblet cell Cl, ciliated cell bar = 2 p,m.

The Aqueous Lining Layer and the Air-Liquid Interface of the Alveoli... 

FIGURE 10 In vitro rates of release of progesterone from PCL films, illustrating their dependence on the film thickness and drug load. The deviation from (time)l/2 kinetics reflects the contribution of an aqueous boundary layer. The solid lines were calculated assuming an aqueous boundary layer thickness of 19 ym. (From Ref. 68.)... 

Figure 19.12 (a) Experimental setup to determine the exchange dynamics of a combined NAPL-water system using the slow stirring method (SSM). (6) - (d) Measured and calculated aqueous concentrations of benzene m/p-xylene and naphthalene. The solid lines give the result of the linear bottleneck exchange model with an aqueous boundary layer thickness of 8bl = 2.4 x 1CT2 cm = 240 pm (adapted from Schluep et al., 2000). 

The surfactant film at the air-mucus interface is probably important for the rheological properties of the extracellular layer by stabilizing the aqueous layer mechanically and by reducing the evaporation of water (54,93). These are well-known functions of surfactant films if spread on top of a water surfaee (94). Fluid balance in the airway lining layer may also be influenced by the recently demonstrated effeet of surfactant in stimulating chloride secretion by airway epithelial cells (95). 

The lag-phase measurement at 234 nm of the development of conjugated dienes on copper-stimulated LDL oxidation is used to define the oxidation resistance of different LDL samples (Esterbauer et al., 1992). During the lag phase, the antioxidants in LDL (vitamin E, carotenoids, ubiquinol-10) are consumed in a distinct sequence with a-tocopherol as the first followed by 7-tocopherol, thereafter the carotenoids cryptoxanthin, lycopene and finally /3-carotene. a-Tocopherol is the most prominent antioxidant of LDL (6.4 1.8 mol/mol LDL), whereas the concentration of the others 7-tocopherol, /3-carotene, lycopene, cryptoxanthin, zea-xanthin, lutein and phytofluene is only 1/10 to 1/300 of a-tocopherol. Since the tocopherols reside in the outer layer of the LDL molecule, protecting the monolayer of phospholipids and the carotenoids are in the inner core protecting the cholesterylesters, and the progression of oxidation is likely to occur from the aqueous interface inwards, it seems reasonable to assign to a-tocopherol the rank of the front-line antioxidant. In vivo, the LDL will also interact with the plasma water-soluble antioxidants in the circulation, not in the artery wall, as mentioned above. 

Figure 3. Sensitivity curves of SPP image reversal (solid line) after 20kV EB exposure compared with a novolac-based resist (dashed line). A 0.3 //m thick resist layer was exposed to EB followed by a flood exposure using near UV radiation and then dip-developed in an aqueous THAH solution for 60 s at 25°C. TMAH concentration A 0.65 wt%, B 0.70 wt%, C 0.80 wt%, D 1.2 wt%.

CEL dye. A CEL solution was obtained by dissolving poly(N-vinylpyrrolidone) (PVP) (7 g) and Dl (5.8 g) in 50 wt% aqueous acetic acid. (87.2 g). The CEL layer was spin-coated onto a photoresist, RI-7000P (Hitachi Chemical Co.), and baked at 80T for 20 minutes. Exposure was performed with an in-house i-line reduction projection aligner. The resist was developed in a 2. 38 wt% tetramethylammonium hydroxide aqueous solution. The film thickness was measured with an Alpha-step 200 (Tencor)... 

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