Role of coupling delay in oscillatory activity in autonomous networks of excitable neurons with dissipation

We study numerically the effects of time delay in networks of delay-coupled excitable FitzHugh Nagumo systems with dissipation. The generation of periodic self-sustained oscillations and its threshold are analyzed depending on the dissipation of a single neuron, the delay time, and random initial conditions. The peculiarities of spatiotemporal dynamics of time-delayed bidirectional ring-structured FitzHugh-Nagumo neuronal systems are investigated in cases of local and nonlocal coupling topology between the nodes, and a first-order nonequilibrium phase transition to synchrony is established. It is shown that the emergence of oscillatory activity in delay-coupled FitzHugh-Nagumo neurons is observed for smaller values of the coupling strength as the dissipation parameter decreases. This can provide the possibility of controlling the spatiotemporal behavior of the considered neuronal networks. The observed effects are quantified by plotting distributions of the maximal Lyapunov exponent and the global order parameter in terms of delay and coupling strength.Comment: 14 pages, 17 figure

ENGINEERING OF MEDICAL DATA PROCESSING WEB PORTAL

Medical data processing web portal for medical scientists. The web portal will combine medical data from different scientists to conduct collaborative research.Работа выполнена в рамках государственного задания ФГБОУ ВО УГМУ Минздрава России на 2021 г. № 056-00054-21-00 от 17.12.2020 г., тема: «Индивидуализация подбора комплексной геропрофилактической терапии»

Archaeal communities of frozen Quaternary sediments of marine origin on the coast of Western Spitsbergen,

The archaeal composition of permafrost samples taken during drilling of frozen marine sediments in the area of the Barentsburg coal mine on the east coast of Grønfjord Bay of Western Spitsbergen has been studied. The study was based on the analysis of the V4 region of the 16S rRNA gene, carried out using next generation sequencing. This is the second part of the work dedicated to the prokaryotic composition of the Western Spitsbergen, the fi rst part was devoted to the domain of Bacteria. The general phyla of the the Archaea domain were Euryarchaeota, Bathyarchaeota, Thaumarchaeota and Asgardarchaeota. As a result of phylogenetic analysis of the dominant operational taxonomic units, representatives of methanogenic methane- and ammonium-oxidizing archaea, as well as heterotrophic archaea were found. Methanobacteria class of methanogenic archaea was found in the controversial genesis, while methane-oxidizing archaea of the Methanomicrobia class of Methanosarcinales order were found in the marine permafrost of Cape Finneset: ANME-2a, -2b group was found in layers 8.6 and 11.7 m, and a group ANME-2d (Candidatus Methanoperedens) – in a layer of 6.5 m. Ammonium-oxidizing archaea of the phylum Thaumarchaeota was present in all types of permafrost, while Nitrososphaerales was detected in controversial genesis permafrost, and the order-Nitrosopumilales in the marine permafrost or controversial genesis ones. Representatives of phylum Bathyarchaeota were found in the stratigraphicly most ancient samples under this study. Superphylum Asgardarchaeota was met exclusively in the layers of permafrost with marine genesis and was represented by phyla Lokiarchaeota, Thorarchaeota and another group belonging to this superphylum that was not identified by us. The presence in the marine permafrost terrace of Cape Finneset at 11.7 m depth of methane, ethylene and ethane, as well as the composition of the archaeal community gives this layer to assume in it the presence of microbiological processes of the anaerobic oxidation of methane, probably received from Tertiary deposits before freezing. The results obtained are represented the permafrost of Spitsbergen as a rich archive of genetic information of little studied prokaryotic groups

Farit Gabidinovich Avkhadiev (on his 70th birthday)

This article about mathematical results of F.G. Avkhadiev

Comparative Evaluation of Custom-Made Components and Standard Implants for Acetabular Reconstruction in Revision Total Hip Arthroplasty

Background.The use of custom-made acetabular components is one of the promising methods for reconstruction of the acetabulum in cases of significant defects, including those associated with pelvic bone dissociation. It allows achieving stable fixation and restoring the biomechanics of the hip joint. Aimofthestudy to compare the results of using individually designed components, supportive antiprotrusion rings, augments, and hemispherical components in revision total hip arthroplasty for type IIIB bone defects according to Paprosky classification. Methods.The study analyzed the treatment outcomes of 90 patients with type IIIB bone defects who underwent revision total hip arthroplasty between 2017 and 2022. Patients were divided into three groups: the first group received individually designed acetabular components, the second group received augments with hemispheres, and the third group had antiprotrusion cages implanted. The analysis included the reasons for revision surgery, operation duration, blood loss volume, and type of revision procedure. Pain and functional outcomes were assessed with WOMAC, Harris Hip Score, and VAS scales. Results.3D-printed constructs were more frequently implanted in patients with pelvic bone dissociation. The first group showed a significantly positive dynamic in functional outcomes. Complications were diagnosed in 27 (30%) cases: joint instability (dislocation) in 10 (11.1%) patients, periprosthetic infection in 8 (8.8%), aseptic loosening in 4 (4.4%), and sciatic nerve neuropathy in 5 (5.5%) patients. The number of these complications was higher in the second and third groups of patients. Conclusion.Custom-made implants using 3D technologies are a preferable option for revision total hip arthroplasty in patients with type IIIB defects according to Paprosky classification, especially in cases of pelvic bone dissociation