Mathematics

The system of kinetic equations was proposed describing the joining of heterogeneous DNA fragments by DNA-ligase. The DNA fragments were considered as flexible rods and characterized only by molecular weights and concentrations. The program for calculating the concentrations of all circular and linear DNA forms is described. The program has been written in FORTRAN IV and calculations were made with EC 10--10. For the maximal yield of the multimeric circular DNA molecules it is recommended to begin the ligation at a high DNA concentration and then after a certain fixed time to dilute the reaction mixture. The optimum time intervals and ratios of fragment concentrations were calculated. The yield of different ligation products has been determined. The calculations of optimum reaction conditions were carried out for the construction of hybrid molecules containing DNA fragments with or without selective genetic markers.

The kinetics of different DNA forms formation were studied during the ligation reaction. Reaction was carried out using as a model BamH1 DNA fragments of plasmid pBR322 and DNA-ligase of bacterophage T4. The products of the reaction were separated with 1% agarose gel, followed by DNA quantitation in the corresponding bands by scanning fluorimeter. The kinetics of the ligation reaction were measured in the range of DNA concentrations from 1 to 100 micrograms/ml. The system of differential equations, that described the kinetics of the ligation reaction, was obtained. This has no analytical solution, but may be approximately calculated with a computer. The analysis of kinetic equations was made in order to optimize the ligation reaction. The optimal DNA concentrations were found allowing the maximal yield of multimer circular DNA forms. The simple formula for calculatng these concentrations were developed. The yield of circular DNA multimers might be increased if the reaction is carrie...

The Karhunen-Loeve (KL) Transform is an optimal method for approximating a set of vectors or images, which was used in image processing and computer vision for several tasks such as face and object recognition. Its computational demands and its batch calculation nature have limited its application. Here we present a new, sequential algorithm for calculating the KL basis, which is

The extent to which phonological, visual-spatial short-term memory (STM), and nonsymbolic quantitative skills support the development of counting and calculation skills was examined in this 14-month longitudinal study of 125 children. Initial assessments were made when the children were 4years 8months old. Phonological awareness, visual-spatial STM, and nonsymbolic approximate discrimination predicted growth in early calculation skills.These results suggest that both the approximate number system and domain-general phonological and visual-spatial skills support early calculation. In contrast, only performance on a small nonsymbolic quantity discrimination task (where the presented quantities were always within the subitizing range) predicted growth in cardinal counting skills. These results suggest that the development of counting and the development of calculation are supported by different cognitive abilities.

This paper investigates a vertical-cavity surface-emitting laser (VCSEL) model in which the first two, rotationally symmetric, linearly polarised optical modes (LP01 and LP02) are excited. A general form of optical feedback is studied, in which the electric fields of the two modes can couple via the external-cavity round-trip. This is in contrast to previous studies in which each field receives

Argumentation-based negotiation approaches have been proposed to capture realistic negotiation contexts where all issues being negotiated are not fixed a priori and the negotiatorýs beliefs may be influenced during the negotiation process. We have proposed a novel Bayesian network based argumentation and decision making framework that allows agents to utilize models of other agents. We discuss a decision mechanism for

An increase in demand for medicinal herbs and their recognized secondary metabolites as active ingredients has been observed in recent decades. Due to boom in herbal industry an overuse of herbs has lead to extinction or has lowered the supply of lead compounds. ...