Predator population depending on lemming cycles

In this paper, a Langevin equation for predator population with multiplicative correlated noise is analyzed. The noise source, which is a nonnegative random pulse noise with regulated periodicity, corresponds to the prey population cycling. The increase of periodicity of noise affects the average predator density at the stationary state

Stochastic model for the epitaxial growth of two-dimensional islands in the submonolayer regime

The diffusion-based growth of islands composed of clusters of metal atoms on a substrate is considered in the aggregation regime. A stochastic approach is proposed to describe the dynamics of island growth based on a Langevin equation with multiplicative noise. The distribution of island sizes, obtained as a solution of the corresponding Fokker-Planck equation, is derived. The time-dependence of island growth on its fractal dimension is analysed. The effect of mobility of the small islands on the growth of large islands is considered. Numerical simulations are in a good agreement with theoretical results

Bioinformatics education course on gene networks reconstruction using online tools

Bioinformatics education requires the use of online computer tools for modeling protein-protein interactions, visual presentation of the networks, access to open databases. The usage of online bioinformatics tools makes it possible to reconstruct both protein and genes networks, and develop modeling skills for students. We consider the issues of computer reconstruction of gene networks - complexes of interacting macromolecules - using a list of genes associated with a particular disease, or a complex disorder based on public online bioinformatics tools - STRINGDB, GeneMANIA, Metascape, Cytoscape applications. Examples of computer reconstruction and visualization of gene networks of oncological diseases including glioma, breast cancer, as well as complex mental disorders such as Parkinson’s disease, schizophrenia, were recently published in co-authorship with the students. The use of only online bioinformatics tools is educational in nature, focused on students, both in mathematics and in natural sciences and medical disciplines, who do not have enough skills in computer science, programming, and writing their own code. Automatic construction of lists of genes associated with a disease using open databases (OMIM, GeneCards, MalaCards), computer reconstruction of gene networks, calculations of enrichment statistics for gene ontology categories have been successfully mastered by students. The educational bioinformatics materials designed for the students and with the students were tested at several universities in Russia, including courses in English for foreign students studied in Russia. The tasks of digitalization of medicine, the development of IT technologies are in the priority. The epidemic situation that has existed in recent years and the forced transition to distance learning had accelerated the adoption of measures to change the formats of education, the emergence of new learning platforms. Note a number of qualitatively new tasks of education in the field of digital healthcare, such as the use of blockchain technologies, the use of Artificial Intelligence (AI) methods in support of medical decision-making. Overall, the educational course developed includes a theoretical part (video lessons) and a practical part - performing tasks on the use of computer programs and databases that have found a number of applications for medical problems in the reconstruction and analysis of networks of interactions of macromolecules.Book of abstract: 4th Belgrade Bioinformatics Conference, June 19-23, 202

Quantum-enhanced interferometer using Kerr squeezing

©2023 the author(s). Ministry of Science and Higher Education of the Russian Federation (dx.doi.org/10.13039/501100003443) (Megagrant No. 075-15-2021-633); Russian Foundation for Basic Research (dx.doi.org/10.13039/501100002261) (19-29-11032); Foundation for the Advancement of Theoretical Physics and Mathematics “BASIS” (dx.doi.org/10.13039/501100012708), Ministerio de Ciencia e Innovación https://dx.doi.org/10.13039/501100004837) (Grant No. PID2021-127781NB-I00).One of the prime applications of squeezed light is enhancing the sensitivity of an interferometer below the quantum shot-noise limit, but so far, no such experimental demonstration was reported when using the optical Kerr effect. In prior setups involving Kerr-squeezed light, the role of the interferometer was merely to characterize the noise pattern. The lack of such a demonstration was largely due to the cumbersome tilting of the squeezed ellipse in phase space. Here, we present the first experimental observation of phase-sensitivity enhancement in an interferometer using Kerr squeezing.Depto. de ÓpticaFac. de Ciencias FísicasTRUEMinisterio de Ciencia e Innovación (MICINN)pu

Observation of robust polarization squeezing via the Kerr nonlinearity in an optical fibre

Squeezed light is one of the resources of photonic quantum technology. Among the various nonlinear interactions capable of generating squeezing, the optical Kerr effect is particularly easy-to-use. A popular venue is to generate polarization squeezing, which is a special self-referencing variant of two-mode squeezing. To date, polarization squeezing generation setups have been very sensitive to fluctuations of external factors and have required careful tuning. In this work, we report on a development of a new all-fibre setup for polarization squeezing generation. The setup consists of passive elements only and is simple, robust, and stable. We obtained more than 5 dB of directly measured squeezing over long periods of time without any need for adjustments. Thus, the new scheme provides a robust and easy to set up way of obtaining squeezed light applicable to different applications. We investigate the impact of pulse duration and pulse power on the degree of squeezing

The use of argon plasma coagulation in mammoplasty as a prevention of postoperative complications

The frequency of reoperations associated with complications after mammoplasty reaches 15 % during the first year. There are many ways and means for processing the soft tissues of the breast during mammoplasty, helping to reduce the risk of postoperative complications. The purpose of this work was to develop an algorithm for the application of the argon plasma technique for tissue treatment in mammoplasty. Material and methods. The study included 30 females aged 23 to 46 who underwent mammoplasty. The patients were divided into 2 groups of 15 people. In group 1, standard methods of processing soft tissues were used, and in group 2, the argon plasma technique was used in conjunction with the use of Aristo glue. Patients were observed in the early, late and distant postoperative period. Results. In the course of the study, in addition to the excellent coagulation and bactericidal action of argon plasma, the effect of “pulling up” the soft tissues of the mammary gland was found, which, in case of ptosis of I and II degrees, made it possible to use a smaller implant to achieve an optimal aesthetic result. Also, when using the argon plasma technology, no inflammatory processes were observed, the amount of exudative fluid in the drains decreased, the pain syndrome was significantly less pronounced in comparison with patients who underwent the standard method of tissue processing. Conclusions. This study confirms the fact that the use of argon plasma coagulation in the processing of breast tissue has a significant number of advantages compared to standard methods