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The Russian business community has realized the need for project/targeted programme management procedures; therefore, the demand for customized project-oriented management methods goes up. In the meantime, this demand is not supplied in full, and the supply is far from being efficient. Project management methodologies need further improvement, including development of portfolio management processes applicable to investment projects developed and implemented in the construction industry. The article considers General approaches to the formalization of the management of portfolios of investment–construction projects. For the main groups of processes portfolio management (“Formation and alignment”, “Monitoring and control” and “Support and development”) deals with their constituent sub-processes. The proposed decomposition can be used for both portfolio construction and investment projects and also has an invariant character, which allows extending the proposed approaches to other system target–oriented and project–oriented management.

The paper deals with the problems of the component simulation method application in the problems of the automation of the mechanical system model formation with the further possibility of their CAD-realization. The purpose of the investigations mentioned consists in the automation of the CAD-model formation of high-speed mechanisms in automatic machines and in the analysis of dynamic processes occurred in their units taking into account their elasto-inertial properties, power dissipation, gaps in kinematic pairs, friction forces, design and technological loads. As an example in the paper there are considered a formalization of stages in the computer model formation of the cutting mechanism in cold stamping automatic machine AV1818 and methods of for the computation of their parameters on the basis of its solid-state model.

Single-stranded DNA generated in the cell during DNA metabolism is stabilized and protected by binding of ssDNA-binding (SSB) proteins. Escherichia coli SSB, a representative homotetrameric SSB, binds to ssDNA by wrapping the DNA using its four subunits. However, such a tightly wrapped, high-affinity protein-DNA complex still needs to be removed or repositioned quickly for unhindered action of other proteins. Here we show, using single-molecule two- and three-colour fluorescence resonance energy transfer, that tetrameric SSB can spontaneously migrate along ssDNA. Diffusional migration of SSB helps in the local displacement of SSB by an elongating RecA filament. SSB diffusion also melts short DNA hairpins transiently and stimulates RecA filament elongation on DNA with secondary structure. This observation of diffusional movement of a protein on ssDNA introduces a new model for how an SSB protein can be redistributed, while remaining tightly bound to ssDNA during recombination and repair processes., The primary activity of SSB proteins in DNA metabolism is to bind preferentially to ssDNA with high affinity independently of sequence (1). However, SSB proteins also have a crucial role [...]

The negative enthalpy change (deltaH(sub obs)) is examined over a much wider temperature range and as a function of monovalent salt concentration and type for SSB binding to (dT)70 under solution conditions that favor the fully wrapped (SSB)65 complex using isothermal titration calorimetry. Over this wider temperature range, a strongly temperature-dependent negative heat capacity change (deltaC(sub p,obs) is observed.

Results show that Escherichia coli homotetrameric SSB protein is transferred from one single-stranded DNA molecule to another with the need for a protein intermediate. Data indicate that the rate of transfer is dependent on the amount of free DNA binding sites within the initital SSB tetramer-single-stranded DNA donor complex.

Research has been conducted on the homotetrameric Escherichia coli SSB protein's binding to the single-stranded oligodeoxynucleotides. The kinetic mechanism of this binding has been investigated under conditions allowing the fully wrapped ssDNA complex formation and the results are reported.