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This paper studies a model of a population with non-overlapping generations and density-dependent regulation of birth rate. The population breeds seasonally, and its reproductive potential is determined genetically. The model proposed combines an ecological dynamic model of a limited population with non-overlapping generations and microevolutionary model of its genetic structure dynamics for the case when adaptive trait of birth rate controlled by a single diallelic autosomal locus with allelomorphs A and a. The study showed the genetic composition of the population, namely, will it be polymorphic or monomorphic, is mainly determined by the values of the reproductive potentials of heterozygote and homozygotes. Moreover, the average reproductive potential of mature individuals and intensity of self-regulation processes determine population dynamics. In particularly, increasing the average value of the reproductive potential leads to destabilization of the dynamics of age group sizes. The intensity of self-regulation processes determines the nature of emerging oscillations, since scenario of stability loss of fixed points depends on the values of this parameter. It is shown that patterns of occurrence and evolution of cyclic dynamics regimes are mainly determined by the features of life cycle of individuals in population. The life cycle leading to existence of non-overlapping generation gives isolated subpopulations in different years, which results in the possibility of independent microevolution of these subpopulations and, as a result, the complex dynamics emergence of both stage structure and genetic one. Fixing various adaptive mutations will gradually lead to genetic (and possibly morphological) differentiation and to differences in the average reproductive potentials of subpopulations that give different values of equilibrium subpopulation sizes. Further evolutionary growth of reproductive potentials of limited subpopulations leads to their number fluctuations which can differ in both amplitude and phase.

The results of homology modeling of HydSL, a NiFe-hydrogenase from purple sulphur bacterium Thiocapsa roseopersicina BBS are presented in this work. It is shown that the models have larger confidence level than earlier published ones; a full-size model of HydSL hydrogenase is presented for the first time. The C-end fragment of the enzyme is shown to have random orientation in relation to the main protein globule. The obtain models have a large number of ion pairs, as well as thermostable HydSL hydrogenase from Allochromatium vinosum, in contrast to thermolabile HydAB hydrogenase from Desulfovibrio vulgaris.

Often decisions in social groups are made by consensus. This applies, for example, to the examination in the technical committee for standardization (TC) before the approval of the national standard by Rosstandart. The standard is approved if and only if the secured consensus in the TC. The same approach to standards development was adopted in almost all countries and at the regional and international level. Previously published works of authors dedicated to the construction of a mathematical model of time to reach consensus in technical committees for standardization in terms of variation in the number of TC members and their level of authoritarianism. The present study is a continuation of these works for the case of the formation of coalitions that are often formed during the consideration of the draft standard to the TC. In the article the mathematical model is constructed to ensure consensus on the work of technical standardization committees in terms of coalitions. In the framework of the model it is shown that in the presence of coalitions consensus is not achievable. However, the coalition, as a rule, are overcome during the negotiation process, otherwise the number of the adopted standards would be extremely small. This paper analyzes the factors that influence the bridging coalitions: the value of the assignment and an index of the effect of the coalition. On the basis of statistical modelling of regular Markov chains is investigated their effects on the time to ensure consensus in the technical Committee. It is proved that the time to reach consensus significantly depends on the value of unilateral concessions coalition and weakly depends on the size of coalitions. Built regression model of dependence of the average number of approvals from the value of the assignment. It was revealed that even a small concession leads to the onset of consensus, increasing the size of the assignment results (with other factors being equal) to a sharp decline in time before the consensus. It is shown that the assignment of a larger coalition against small coalitions takes on average more time before consensus. The result has practical value for all organizational structures, where the emergence of coalitions entails the inability of decision-making in the framework of consensus and requires the consideration of various methods for reaching a consensus decision.