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

Innovative Unified Approach to Enterprise Interoperability

В последнее время все больше внимания уделяется понятию «блокчейн». Большинство специалистов проводит прямую параллель с биткоином (современной цифровой валютой), но мало кто задумывался о его технических возможностях: блокчейн может быть использован как инструмент облачного взаимодействия на предприятии, обеспечивающий высокий уровень интероперабельности систем и защищенность данных, так необходимых оборонным предприятиям. По мнению авторов, применение блокчейна в системе управления предполагает, что объектом управления будет являться децентрализованная распределенная система, а сама система управления будет характеризоваться определенными свойствами, а именно: транспарентность системы, высокая степень защиты интеллектуальной собственности, наглядность процессов.Recently, more and more attention has been paid to the concept of «blockchain». Most experts draw a parallel with bitcoin (a modern digital currency), but few people have thought about its technical capabilities: the blockchain can be used as a tool for cloud interaction in the enterprise providing a high level of system interoperability and data security, so necessary for defense enterprises. According to the authors, the use of blockchain in the management system assumes that the object of management will be a decentralized distributed system, and the management system itself will be characterized by certain properties, namely: transparency of the system, a high degree of intellectual property protection, visibility of processes

FIVE YEAR OUTCOMES OF CERAMIC-ОN-CERAMIC AND CERAMIC-ОN-POLYETHYLENE BEARINGS IN HIP JOINT REPLACEMENT

In view of the increasing number of hip joint replacement volume there remains the key issue of improving prosthesis survivorship which directly depends on the friction couple. Material and methods. The authors have analyzed five year outcomes of two bearing types (head and insert) used in hip replacement: ceramic-on-ceramic (CoC) in 324 patients and ceramic-on-polyethylene (CoP) in 300 patients. Totally 550 patients were operated in the period starting 2010 till 2014, including 74 patients underwent bilateral hip replacement. The authors divided patients based on gender and also into three age groups: 20-40, 41-60 and 61-80 years old. The largest group comprised 156 women aged 41-60 years (28.4%). Additional grouping of patients was made based on gender, age and bearing diameter.36 mm diameter bearing was characterized of the most frequent use. Functional outcomes were assessed by Harris Hip Score. Statistical analysis was made with Statistica 10 software. Statistical significant was observed at p<0.05.Results.28 mm diameter bearing were rarely (19.5%) applied and mainly in women which is related to need for use of smaller acetabulum components and inability to implant a larger insert.36 mm diameter bearing were used most frequently, CoC articulation of36 mm was used in men in 34% of cases and in women – in 18.12% of cases.40 mm articulations were implanted in women two times less than in men which is related to a smaller diameter of acetabulum in women. Generally, CoC bearings were implanted more often in men which can be explained by a bigger social demand as well as a higher anti-luxation stability of large diameter bearings. Dislocations of implants occurred in 5 (0.91%) patients: in 4 patients with CoP bearingand in one patient with CoC articulation. Four revision procedures (0.64%) were made due to deep periprosthetic infection: two surgeries in each group. Harris Hip Score evaluation in CoC group demonstrated excellent and good outcomes in 99.2% of cases, and in CoP group – in 97.5% of cases.Conclusion. The authors observed no ceramic fractures or acoustic effects during 60 months follow up. It’s reasonable to increase CoC bearing diameter to achieve a better anti-luxation effect. CoC bearing selection should depend on patient’s activity and social demands but not only on the age. Based on study observations the authors forecast a higher survivorship of CoC couple within 15-20 years and expect to prove this conclusion in further studies

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

Обоснование параметров машинной технологии приготовления органобактериальных удобрений

Questions connected with a solution of a problem of providing plants with nitrogen by means of nitrogen-fixing biological preparations application were considered. Requirements to quality of organo-bacterial fertilizers preparation on the basis of composts and the nitrogen-fixing biological preparations of Extrasol group were stated. Theoretical and experimental researches for justification of possibility of biological products application together with peat-manure composts were conducted. A project of technological process and experimental facilities for organo-bacterial mix preparation with a set quality level of biological product distribution in compost were developed. In the course of experiment the time length of mixing was modified from 1 to 12 min. There were set the values of rotation frequency of a rotor mixer: 40, 60, 80 and 100 rpm. Uniformity of biological product distribution in the mix was estimated by coefficient of a variation of a control element for which sugar beet seeds were used. It was revealed that quality of biopreparation distribution in the compost mass depends on the rotor mixer rotation frequency and time length of mixing. At the constant mixing time with increase in frequency of rotation quality of distribution in the mass of the control element estimated by variation coefficient at first decreases, and then at achievement of the frequency of 65-70 rpm it starts to increase. Quality of distribution is influenced positively also by time length of mixing. With the constant frequency of rotor mixer rotation uniformity of mixing was stabilized after 3-4 min. When facilities loading to 50 kg of mix (49 kg of compost +1 kg of a biological product) the coefficient of a control element variation characterizing distribution quality made 10-13 percent with a frequency of rotation of 65 rpm and time of mixing of 3 min.Рассмотрели вопросы, связанные с решением проблемы обеспечения растений азотом посредством применения азотофиксирующих биопрепаратов. Изложили требования к качеству приготовления органо-бактериальных удобрений на основе компостов и азотофиксирующих биопрепаратов группы Экстрасола. Провели теоретические и экспериментальные исследования по обоснованию возможности применения биопрепаратов совместно с торфо-навозными компостами. Разработали проект технологического процесса и экспериментальную установку для приготовления органо-бактериальной смеси с заданным уровнем качества распределения биопрепарата в компосте. В процессе эксперимента изменяли продолжительность перемешивания от 1 до 12 мин. Установили значения частоты вращения ротора-смесителя: 40, 60, 80 и 100 об/мин. Равномерность распределения биопрепарата в смеси оценивали коэффициентом вариации контрольного элемента, в качестве которого использовали семена сахарной свеклы. Выявили, что качество распределения биопрепарата в массе компоста зависит от частоты вращения ротора-смесителя и времени перемешивания. При фиксированном времени перемешивания с увеличением частоты вращения качество распределения в массе контрольного элемента, оцениваемого коэффициентом вариации, сначала уменьшается, а затем при достижении частоты 65-70 об/мин начинает увеличиваться. На качество распределения положительно влияет также продолжительность перемешивания. При фиксированной частоте вращения ротора-смесителя по истечении 3-4 мин равномерность перемешивания стабилизируется. Определили, что при загрузке в установку до 50 кг смеси (49 кг компоста + 1 кг биопрепарата) коэффициент вариации контрольного элемента, характеризующий качество распределения биопрепарата, составил 10-13 процентов при частоте вращения 65 об/мин и времени перемешивания 3 мин

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

Сравнительный анализ плотности печени по данным КТ и низкодозной КТ органов грудной клетки

The introduction of LDCT-based screening programs into clinical practice allows an additional assessment of the liver. It is known that medium-to-severe steatosis can be detected using LDCT. However, taking into account the increased image noise level and the fact that the liver is always only partly in the scan area, the question arises as to how accurately the liver density can be determined in LDCT relative to routine CT.Purpose. Thus, the following objectives of this study have been established:• To identify the differences between the mean density of the liver as measured by a CT and an LNDT.• To compare the mean density between CT and LDCT in different patient subgroups depending on the mean liver density (<40 HU, 40–50 HU, 50–60 HU, and >60 HU).• To determine the effect of image noise level on the mean liver density values on LDCT compared to CT.Materials and methods. We analyzed 30000 patient records from 2017 to 2019.Inclusion criteria: We included patients with both thoracic non-contrast CT and an LDCT and the time interval between the studies of less than 27 days.Exclusion criteria: The absence of CT-LDCT pair, presence of focal liver lesions, known liver diseases, operated liver, anemia with blood density decrease below 40 HU, hands along the body instead of overhead.Study protocol: LDCT was performed at 135 kV. The routine CT was at 120 kV. Scan length: from lung apex to pleural sinuses. The average radiation dose with LDCT was 0.6–0.8 mSv, and 2.8–4.6 mSv with routine CT. All scans were performed on two 64-detector units from the same manufacturer.We measured liver density with the CTLiverExam software algorithm for automatic liver densitometry.The statistical processing was done using the Stata14 program.Results. We used data from 61 patients for statistical analysis. The average age was 53 years. The ratio of men to women was 23:38.We did not observe statistically significant differences between CT and LDCT. With a breakdown by the initial liver density level, it turned out that in the subgroup 40-50 HU, the differences were statistically significant. No correlation between liver density and standard deviation for CT was revealed (p = 0.338). There was a mild anticorrelation for LDCT with a coefficient of -0.686 (p < 0.0001).Conclusion. Our study shows that liver density measurement in thoracic LDCT is valid. In the context of lung cancer screening programs. An analysis of the image noise/liver density ratio on the LDCT shows an inversely proportional relationship: the higher the noise level, the more significant a “decrease” in liver density. This factor must be taken into account when interpreting the results CT and LDCT.Жировой гепатоз – распространенный вид патологии, своевременное выявление которой позволяет избежать прогрессирования заболевания и развития необратимых изменений. Известно, что по данным стандартной компьютерной томографии (КТ) и низкодозной КТ (НДКТ) можно достоверно выявлять стеатоз средней и тяжелой степеней, в том числе при исследовании органов грудной клетки (ОГК). Таким образом внедрение в клиническую практику скрининговых программ с помощью НДКТ позволяет проводить дополнительную оценку состояния печени.Цель исследования: оценка возможностей корректного определения средней плотности печени при НДКТ ОГК для выявления признаков жирового гепатоза при проведении скрининговых исследований.Материал и методы. Проанализированы результаты КТ и НДКТ ОГК 30 000 пациентов, выполненных за период 2017–2019 гг. Критериями включения в разработку являлось наличие у пациента данных КТ и НДКТ в промежутке менее 27 дней между исследованиями. Исследования, при которых в печени выявлены образования, пациенты после операций на печени, с анемией, при снижении плотности крови менее 40 HU, с опущенными вдоль туловища руками во время исследования и при некорректной сегментации печени при обработке изображений не включались в анализ.Исследования НДКТ и КТ были выполнены на 64-срезовых томографах. Протяженность сканирования: от верхушки легких до плевральных синусов. Напряжение при низкодозном протоколе было равно 135 кВ, при стандартном – 120 кВ. Средняя лучевая нагрузка при НДКТ составила 0,6–0,8 мЗв, при стандартной КТ – 2,8–4,6 мЗв.Автоматический анализ изображений проводился с помощью разработанного ПО для автоматического измерения плотности печени, статистический анализ – с помощью программы Stata14 (StataCorp LLC, College Station, Texas, США).Результаты. Отобраны результаты исследований 61 пациента, которые соответствовали заданным критериям. Соотношение мужчин к женщинам составило 23:38, средний возраст – 53 года.При сравнительной оценке рентгенологической плотности печени при КТ и НДКТ на всей выборке  статистически значимых отличий не выявлено (p < 0,480), при этом отмечалось незначительное повышение средних значений плотности при использовании низкодозных протоколов сканирования: 52,81 HU при НДКТ и 51,88 HU при КТ.Оценка исследований, разбитых на подгруппы в зависимости от плотности печени, показала, что в подгруппе  40–50 HU полученные данные отличаются статистической значимостью (p < 0,0003), тогда как в остальных группах подобная взаимосвязь не выявлена (p < 0,753, p < 0,269, p < 0,077). При НДКТ отмечена средняя антикорреляция между плотностью и среднеквадратическим отклонением с коэффициентом -0,686 (p < 0,0001).Обсуждение. Результат статистического анализа показал, что данные плотности печени при НДКТ сопоставимы с КТ. Это позволяет выявлять пациентов с жировым гепатозом средней и тяжелой степеней,не повышая дозу лучевой нагрузки.Анализ влияния шумовых помех на плотность печени при НДКТ показал, что чем выше уровень шума, тем интенсивнее снижаются данные плотности печени, что необходимо учитывать при трактовке результатов. Отсутствие единых значений плотности печени, различающих ее нормальные значения от сниженных, затрудняет интерпретацию данных, находящихся в диапазоне 40–50 HU, что требует проведения дальнейших исследований