Anomalously Slow Domain Growth in Fluid Membranes with Asymmetric Transbilayer Lipid Distribution

The effect of asymmetry in the transbilayer lipid distribution on the dynamics of phase separation in fluid vesicles is investigated numerically for the first time. This asymmetry is shown to set a spontaneous curvature for the domains that alter the morphology and dynamics considerably. For moderate tension, the domains are capped and the spontaneous curvature leads to anomalously slow dynamics, as compared to the case of symmetric bilayers. In contrast, in the limiting cases of high and low tensions, the dynamics proceeds towards full phase separation.Comment: 4 pages, 5 figure

Studies on the growth of the marine microalga Dunaliella salina (Teodoresco)

The present paper reports on the growth pattern of Dunaliella salina cells cultured in different salinities and also in stressed conditions on exposure to mutagens (UV and PEG). The cultures were maintained in different salinities viz., 20, 25, 30, 35, 40, 45 and 50 ppt for a period of two weeks in triplicates and the growth rate was monitored. The peak growth (14.29 lakhs) was observed in 35 ppt on eleventh day indicating the ideal salinity for the culture of this species. The cultures in mid-exponential growth phase were exposed to UV light for 30 and 60 minutes and PEG at four doses viz. 0.125, 0.25, 0.5 and 1 gm/ml. Poorest cell growth was observed for half an hour UV treated cultures (3.51 lakhs/ml). A proportionate decrease in cell count was noticed with increase in the concentration of PEG

Domain Growth, Budding, and Fission in Phase Separating Self-Assembled Fluid Bilayers

A systematic investigation of the phase separation dynamics in self-assembled multi-component bilayer fluid vesicles and open membranes is presented. We use large-scale dissipative particle dynamics to explicitly account for solvent, thereby allowing for numerical investigation of the effects of hydrodynamics and area-to-volume constraints. In the case of asymmetric lipid composition, we observed regimes corresponding to coalescence of flat patches, budding, vesiculation and coalescence of caps. The area-to-volume constraint and hydrodynamics have a strong influence on these regimes and the crossovers between them. In the case of symmetric mixtures, irrespective of the area-to-volume ratio, we observed a growth regime with an exponent of 1/2. The same exponent is also found in the case of open membranes with symmetric composition

Video Feature Extraction Based on Modified LLE Using Adaptive Nearest Neighbor Approach

Locally linear embedding (LLE) is an unsupervised learning algorithm which computes the low dimensional, neighborhood preserving embeddings of high dimensional data. LLE attempts to discover non-linear structure in high dimensional data by exploiting the local symmetries of linear reconstructions. In this paper, video feature extraction is done using modified LLE alongwith adaptive nearest neighbor approach to find the nearest neighbor and the connected components. The proposed feature extraction method is applied to a video. The video feature description gives a new tool for analysis of video

Proof by analogy in mural

One of the most important advantages of using a formal method of developing software is that one can prove that development steps are correct with respect to their specification. Conducting proofs by hand, however,can be time consuming to the extent that designers have to judge whether a proof of a particular obligation is worth conducting. Even if hand proofs are worth conducting, how do we know that they are correct? One approach to overcoming this problem is to use an automatic theorem proving system to develop and check our proofs. However, in order to enable present day theorem provers to check proofs, one has to conduct them in much more detail than hand proofs. Carrying out more detailed proofs is of course more time consuming. This paper describes the use of proof by analogy in an attempt to reduce the time spent on proofs. We develop and implement a proof follower based on analogy and present two examples to illustrate its characteristics. One example illustrates the successful use of the proof follower. The other example illustrates that the follower's failure can provide a hint that enables the user to complete a proof