It has been observed in case studies that computer systems evolve through three main processes: initial development, adaptive maintenance, and replacement. Often one system replaces several existing ones. Models of system evolution should therefore include the these processes for all the systems being affected. Sometimes, the cumulative effect of small improvements made during adaptive maintena...

Using the framework of kernelization we study whether efficient preprocessing schemes for the Special Treewidth problem can give provable bounds on the size of the processed instances. In this paper it is shown that Special Treewidth has a kernel with O(`) vertices, where ` denotes the size of a vertex cover. This implies that given an instance (G, k) of Special Treewidth we can efficiently red...

In chicken oocytes, proteins of the K/J family or their analogs, such as are known to be involved in mRNA processing in humans, are closely associated with nascent C-rich RNA transcripts on the loops of lampbrush chromosomes. Using labelled single stranded nucleotide probes and an antibody to protein K, these C-rich transcripts have been mapped to six different pairs of lampbrush loops situated...

When thin brittle rods such as dry spaghetti pasta are bent beyond their limit curvature, they often break into more than two pieces, typically three or four. With the aim of understanding these multiple breakings, we study the dynamics of a bent rod that is suddenly released at one end. We find that the sudden relaxation of the curvature at this end leads to a burst of flexural waves, whose dy...

The formation or suppression of particular structures is a major change occurring in development and evolution. One example of such change is the absence of the seventh abdominal segment (A7) in Drosophila males. We show here that there is a down-regulation of EGFR activity and fewer histoblasts in the male A7 in early pupae. If this activity is elevated, cell number increases and a small segme...

Carbon nanotubes (CNTs) were deposited on various substrates namely untreated silicon and quartz, Fe-deposited silicon and quartz, HF-treated silicon, silicon nitride-deposited silicon, copper foil, and stainless steel mesh using thermal chemical vapor deposition technique. The optimum parameters for the growth and the microstructure of the synthesized CNTs on these substrates are described. Th...