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In the third year of the project we have accomplished its main goal -- a simple, unified description for the swelling of particle-encapsulating vesicles as they approach osmotic lysis, which
is confirmed by experiments. In parallel, we have completed a new theory for the kinetics of micellization.

We have extended the theory for the osmotic swelling of vesicles, which was developed in the first year, to account for membrane stretching. We have shown that the critical behavior, discovered within the original theory, remains present (albeit in a modified form) in the extended theory as well. This implies that the swelling of various vesicles containing various solutes could be described in a unified way -- i.e., swelling curves measured in various experimental systems could be collapsed onto a single universal curve upon proper rescaling. Thanks to a collaboration with the experimental group of Dr. P. Peterlin (University of Ljubljana), established in the second
year of the project, we have been able to check this remarkable prediction. The theory has been very nicely confirmed. Apart from the theoretical understanding of osmotic swelling, the combination of the new theory and the experiment has yielded two extra benefits: (i) a new and highly accurate method to measure permeability coefficients of various solutes through bilayer membranes; (ii) a rare experimental access to a subtle issue of membrane physics -- the number of effective degrees of freedom participating in the statistical mechanics of a membrane. These results are being prepared for publication. They have been presented in a workshop on thin sheets and membranes at the Aspen Center for Physics in September 2010.

We have developed a new theory for the kinetics of formation of nano-scale amphiphilic aggregates (micelles), which are widely used as self-assembled capsules. A free-energy approach has been employed, which allows treating the various stages of micellization on a single
footing. Our analysis highlights the marked differences in the kinetics of closed systems, containing a fixed amount of amphiphilic molecules, vs. open ones, which are in contact with a reservoir of molecules. These results have been submitted for publication.

The graduate student who worked on models of vesicle swelling, Mr. E. Haleva, received the PhD degree in March 2010. The graduate student who worked on aggregation of amphiphilic molecules, Ms. R. Hadgiivanova, received the PhD degree in August 2010.