No abstract

Effects of surface type and area were shown to be important in the yield of cell-size liposomes, but not in determining their size. The liposomes were prepared by dissolving lipids in a chloroform-methanol solution and then evaporating the solvent under nitrogen in the presence of glass beads. After evaporation of the solvent, which was rapid due to the increased surface area, the dried lipids were then swollen in water at high temperatures (higher than the phase transition of the lipids), which led to formation of giant liposomes. The number of liposomes prepared in the presence of Pyrex glass beads, which increase more than lOO-times the surface. area of lipid-glass contact, is more than 5-times larger than in the control experiments without glass beads. The yield of liposomes in the presence of another type of glass bead was almost the same as in the control experiments. These effects may be due to long-and short-range intermolecular interactions in the glass/water/lipid system.

Real-time control systems typically receive streams of sampled data signals, process them, and generate output to control devices via actuators. Control system components make assumptions about sampling rate and other characteristics, such as filtering, of data streams. These application-specific semantic dependencies and time-sensitive semantic properties are usually not explicit in the source code implementation. This paper discusses an approach to modeling the system architecture of realtime applications, capturing semantic dependencies, and recording time-sensitive properties. Analysis of the model can identify inconsistencies in a system design and can determine the impact of a system change. This architectural dependency model can evolve incrementally to record hidden side effects, as they are discovered during maintenance, and prevent such errors in the future.

No abstract