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Congenital porto-caval shunts are rare and may have a different morphological structure (intra- and extrahepatic shunts, with or without portal blood flow). The main method of treating patients with this pathology is endovascular shunt occlusion. However, in some cases, this method is ineffective. The article contains a description of six clinical examples of surgical treatment of congenital porto-systemic shunts in children. In the diagnosis of congenital portosystemic shunts, the leading role belongs to Doppler ultrasound, multislice computed tomography, and angiography. The indication for surgical treatment was the anatomical features of the shunt, which makes endovascular occlusion technically impossible. In one observation a wide Arantian duct was diagnosed, its open ligation was performed. In another case, the portal vein emptied directly into an aneurysmal dilatation, performed reconstructive plastic surgery on the vessels of the portal vein. In the next observation, a pronounced retrograde blood flow was determined along the dilated inferior mesenteric vein, blood was discharged through the sacral plexus into the internal iliac vein. The left internal iliac vein was isolated and ligated, the dysplastic inferior mesenteric vein was ligated and partially removed. In 2 patients, the portal vein flowed directly into the inferior vena cava in the area of aneurysmal expansion; an operation was performed open ligation of the shunt. In one observation, a deep hypoplasia of the intrahepatic branches of the portal vein was diagnosed, and therefore the restoration of portal blood flow after the closure of the shunt is impossible. The child was sent to decide on a liver transplant. Each case of congenital porto-caval shunts is unique. The surgeon determines the tactics directly during the operation, depending on the morphological structure of the organs, since the preoperative examination does not always give an unambiguous idea.

Bistable relays are widely used in both general and special purpose engineering. Such relays are subdivided according to the construction principle into two groups: bistable electromagnetic polarized relays and bistable electromagnetic latching relays. In the technical literature, there is practically no information on the design of the relay of the second group. This article highlights general issues of their design using the example of high-current relays of the DP-1 series for rated currents from 25 to 100 A, which have been used for a long time in autonomous power supply systems for military equipment. The descriptions of the distinctive features of the relay construction and the principle of its operation are given. The kinematic schemes of the main mechanism of the electromagnetic and contact systems are considered. The example of constructing the opposing characteristics of the relay is shown. The paper provides the replacement scheme for calculating of magnetic system on improved method of sections and assumptions, characteristic of the given relay construction.

Introduction. MRI revealing the epileptogenic foci is the central part of the presurgical evaluation of children with focal-resistant epilepsy. Besides that, MRI seems to be a reliable instrument of treatment optimization and good prognosis. Aim. To identify epileptogenic lesions in children with resistant focal epilepsy by high resolution (HR) MRI and comparing obtained data with postsurgical morphology. Materials and methods. We assessed the results of neuroimaging, EEG, clinical neurological status, and postsurgical morphological data in 65 children with focal epilepsy who had undergone antiepileptic surgery in Russian State Children Hospital, neurosurgery department (Moscow, Russia) from 2016 to 2020. Results. The broad spectrum of epileptogenic lesions was revealed by HR MRI, including focal and diffuse cortical dysplasias (44.6%), cortical post hypoxic gliosis (27.7%), glial tumors (7.7%), Rasmussen encephalitis (10.8%), tuberous sclerosis, and Sturge-Weber syndrome (3%), small angiodysplasias (4.6%) and other. Focal cerebral dysplasia had an obvious superiority as the main etiological factor in focal epilepsy and was approved in 33.8% of all patients. In all cases, epilepsy is characterized by frequent and resistant seizures, inflicting motor arrest, and psycho-emotional deterioration. Conclusion. HR MRI and multidisciplinary investigation have to be unchangeable standards in the presurgical evaluation of children with focal epilepsy. This approach’s effectiveness has reassuring confirmation by high level (95.2%) of total coincidence MRI and morphological results.

In modern physiology, very simplified perceptions of such an essential system for the body as the respiratory system have taken root. The system analysis showed that at a physical load of more than 50 W, the tissue respiratory subsystem is activated, providing a volume blood flow rate adequate to the amount of oxygen consumed, and in the external respiratory subsystem the regulation on oxygen voltage in arterial blood is activated, and the regulation on carbon dioxide voltage is deactivated. The role of respiratory frequency in increasing the rate of diffusion through the alveolar capillary membrane is shown. For physiologists, medical professionals and trainers.

According to research tests, the rolling-and-drawing of metal in nondriven rollers reduces the rolling force by 30 to 32% as compared with the rolling in driven rollers. A new method of determining the friction coefficient for a modified process flow sheet is proposed. As shown by the calculations, continuous strip mills used in the roll-and-draw mode cut the metal strain force by 34 to 41% and the energy costs of strip rolling by 5 to 13%.

Мета: визначити особливості формування та роботи госпітальних округів, їх переваги та недоліки, які виявляють після завершення першого етапу медичної реформи, на прикладі Східного Полтавського госпітального округу, з’ясувати ступінь взаємодії між різними закладами охорони здоров’я для забезпечення якісних медичних послуг при наданні вторинної спеціалізованої медичної допомоги в межах одного госпітального округу. Матеріали і методи. Використано такі загальнонаукові методи дослідження, як статистичний метод, метод економічного аналізу та системний підхід, бібліосемантичний метод. Дослідження ґрунтується на матеріалах, наданих Східним Полтавським округом, офіційних статистичних даних. Результати. Висвітлено проблему створення госпітальних округів та механізм взаємодії закладів охорони здоров’я на прикладі Східного Полтавського госпітального округу. Визначено переваги та недоліки даного підходу під час надання вторинної медичної допомоги. Проведені дослідження вказують на те, що медична реформа, яка зумовила появу госпітальних округів та госпітальних центрів вторинної спеціалізованої медичної допомоги територіально пов’язаних з обласними адміністраціями, є досить ефективною. Система створення лікарень, які надають вторинну спеціалізовану медичну допомогу, дозволяє реалізувати принцип «гроші ходять за пацієнтом» та сприяє загальному розвитку лікарень за рахунок отримання фінансів із міського, районного або обласного бюджету для реорганізації та модернізації медичного закладу. Таким чином, відбувається вдосконалення системи надання медичних послуг, здійснюється перехід на якісно новий рівень, який є повноцінно орієнтованим на задоволення потреб хворого. Висновки. Проведена медична реформа, яка зумовила появу госпітальних округів та госпітальних центрів вторинної спеціалізованої медичної допомоги територіально пов’язаних з обласними адміністраціями, є досить ефективною. Система створення лікарень, які надають вторинну спеціалізовану медичну допомогу, дозволяє реалізувати принцип «гроші ходять за пацієнтом» та сприяє загальному розвитку лікарень за рахунок отримання фінансів із міського, районного або обласного бюджету для реорганізації та модернізації медичного закладу. Таким чином, відбувається вдосконалення системи надання медичних послуг, здійснюється перехід на якісно новий рівень, який є повноцінно орієнтованим на задоволення потреб хворого.

В современной физиологии укоренились весьма упрощенные представления о такой важнейшей для организма системе, как система дыхания. Системный анализ показал, что при физической нагрузке более 50 Вт активизируется подсистема тканевого дыхания, обеспечивающая объёмную скорость кровотока, адекватную величине потребляемого кислорода, а в подсистеме внешнего дыхания активируется регуляция по напряжению кислорода в артериальной крови, и дезактивируется регуляция по напряжению двуокиси углерода. Показана роль частоты дыхания в увеличении скорости диффузии через альвеолярнокапиллярную мембрану. Для физиологов, медицинских работников и тренеров.

Aim. To approve of diagnostic effectiveness of SWAN (SWI) images in revealing of calcium containing epileptogenic substrates in children with resistant focal epilepsy.Materials and methods. The results of MRI in children with refractory focal epilepsy obtained in the Radiology Department of the Russian State Children Hospital in the period from 2018 to 2020 were observed retrospectively. High-resolution epileptological MR protocol used for investigation of 67 children. SWAN was applied in all cases for identification of calcium containing epileptogenic substrates, including cavernomas, DVA syndrome, cortical gangliogliomas, Sturge-Weber syndrome and tuberous sclerosis complex. All images were received by using MRI 3T 750 W Discovery GE.Results. In 17 cases (25%) SWAN provided important diagnostic information about the nature of the of epileptogenic lesion, its prevalence and borders. Additional earlier invisible structural changes were revealed in 2 cases of SWS and 1 cases of FCD; and in 13 cases SWAN gave us possibility to avoid CT for approving calcium in epileptogenic focus.Conclusion. We believe that adding SWAN in to the epileptological MR protocol is the necessary step for optimizing calcium and blood degradation products identification in the structure of potential epileptogenic focuses. Moreover, it would be very effective instrument for differential diagnosis of cerebral structural changes, specifying its etiology and, hence, would have influence on the therapeutic tactic and surgical strategy in children with focal epilepsy.

Tuberous sclerosis is one of the genetically determined neurodermal syndromes, characterized by focal epilepsy, which is resistant to drug therapy in most cases. Tuberous sclerosis has not been surgically treated for a long time due to the multifocal nature of brain damage. However, using new instrumental methods the surgeon can isolate tuber – “drivers”, responsible for epileptic induction, which, therefore, can be a target for surgical removal. The article presents a clinical case of the treatment of pharmacoresistant epilepsy in a 17-year-old girl with tuberous sclerosis and normal neuropsychiatric and cognitive status; the surgeon managed to achieve a complete regression of seizures after the surgical removal of one of the tubers. Using a multimodal complex of examinations, including high-resolution magnetic resonance imaging and invasive electroencephalographic monitoring, the surgeon managed to identify the “inductor” tuber associated with the epileptic initiation zone among multiple cortical tubers. This section of the cerebral cortex was subjected to surgical resection. For the entire postoperative period (16 months) there were no seizures and antiepileptic drugs were canceled; cognitive processes, memory were improved. Thus, active surgical tactics may be effective in more than 50% of patients with tuberous sclerosis and pharmacoresistant epilepsy. This case confirms the need for a multidisciplinary examination prior to the surgery in patients with tuberous sclerosis.

Introduction. Cortical dysplasias (CDs) encompass a wide variety of disorders that in most cases lead to epilepsy, especially in infants and young children. MRI diagnosis of CDs is a major part of presurgical examination of pediatric patients with resistant focal epilepsy.Aim. To identify MR markers of CD in the immature brain and develop an MRI protocol for early diagnosis of CDs.Materials and methods. Children aged Results. The rate of detection of small-size cortical malformations, such as nodular heterotopies or focal cortical dysplasias was significantly higher in groups of patients whose brains (according to MR images) were at the infantile or adult phases of myelination. In children with the isointensive phase myelination, only large cortical dysplasias could be identified. In the first phase, the focal malformations had low amplitude signals in T2-weighted images and high amplitude signals in T1, unlike those in adult patients. In the isointensive phase, the quality of visualization was significantly reduced and provided poor diagnostic information.Conclusion. The results confirm the diagnostic significance of early (before age of 5 months) MRI testing in cases with suspected CD-associated focal epilepsy. However, at the period between 5 and 12 months of age, MR imaging was ineffective for CD diagnosing. Later, in the period from 12 to 15 months, the MRI ability to identify the CDs gradually increased. We consider the standard T2 weighted images with high TR values, the most effective MR modality for diagnosing CDs in young children.

At the moment, the design of various aircraft systems is a complex process in which you have to choose from a large number of competing versions of the developed system. Decisions that were made during development can affect various key factors, including system reliability. In this article a comparative analysis of two variants of hydraulic system power unit design for a heavy twin-engine aircraft with passenger capacity up to 300 people was carried out. For the analysis was taken a number of basic technical solutions, which were applied in such aircraft as A-350, B-787, IL-96, SSJ-100, and several others. As a result of the analysis, the most suitable version of the hydraulic system in terms of reliability and the possibility of implementing this version of the system was selected.

We present a study of the solar-cycle variations of >80 MeV proton flux intensities in the lower edge of the inner radiation belt, based on the measurements of the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) mission. The analyzed data sample covers an ~8 year interval from 2006 July to 2014 September, thus spanning from the decaying phase of the 23rd solar cycle to the maximum of the 24th cycle. We explored the intensity temporal variations as a function of drift shell and proton energy, also providing an explicit investigation of the solar-modulation effects at different equatorial pitch angles. PAMELA observations offer new important constraints for the modeling of low-altitude particle radiation environment at the highest trapping energies., accepted for publication in the Astrophysical Journal Letters

At the moment, the most perspective development direction of the aviation industry is the creation of a more electric aircraft and in this case, there are no bleed systems that taking air from the engine, which is necessary to ensure the operation of the air conditioning system and ice protection system.This article discusses the possibility of using no bleed systems and calculating the required characteristics using mathematical modeling. Simulation results show the operation modes of a centrifugal compressor and using to compare two versions of the air-cooling units in case of rotational speed of compressor is limited.The simulation results presented in this article can be used in the design of compressors for advanced electric air conditioning systems

A suspension formed as a result of ultrasonication of a mixture of graphite with N,N-dimethylformamide has been studied by 1H NMR spectroscopy. The dependence of the width of the 1H NMR signal on the N,N-dimethylformamide content of the suspension has been determined.

The Moon might be considered as an integral detector of Galactic Cosmic Rays (GCR) as it contains on its surface cosmogenic isotopes produced by nuclear reactions. Since the retrieval of lunar regolith cores by Apollo missions, there were numerous attempts to measure concentrations and depth profiles of those isotopes and reconstruct the level of cosmic radiation at 1AU at various time scales, ranging from thousands to millions of years. The data also contains encoded levels of solar activity, as the Sun affects the differential flux of GCRs in a well-known manner. All those attempts showed that our nuclear interaction codes, GEANT4 for example, need corrections to describe the lunar data, be it tweaking of cross-sections or any other methods. There are also such archives on Earth: ice cores and trees. Based on terrestrial modulation potential reconstruction we try to calibrate GEANT4 code in a transparent manner, and also present our estimates on the solar activity on time scales of 0.02 and 3 Myrs. The estimates made using our calibration procedure show values consistent with modern understanding of history of solar modulation potential, and demonstrate the necessity to establish an agreed correction method for the analysis of lunar data. We also compare our results and method with another estimation of solar modulation potential during the last 1 Myr.

The paper is focused on Stefan Czarnowski (1879-1937), early Polish sociologist, one of the founders of professional sociology in Poland, and author of an original concept in the historical sociology of culture. His ideas about forms and ways of functioning of the past in the present as well as mechanisms of nation-building (using the example of St. Patrick as a resource of formation of national identity of Irish people) are considered in the context of history of memory studies and nationalism studies.

In the paper there are presented the main tendencies of the epidemic process in rotaviral infection in the one of the southern region of Ukraine during the span of 1998-2013. There was established the prevalence of the contact-house way of the transmission in 1-year-old infants. There were determined the most spread P and G genotypes of the agent, their widely spread combinations and the dynamic changes of genotypes in this region.

Functional dependencies between all relevant parameters of wheeled vehicles of different drive types and driving conditions with maximum height of obstacle and width of ditch are obtained for the first time. The dependencies allow to ensure at the design stage the optimum axle weight distribution of machine for specified operating conditions, and thus maximum possible traction force and cross-country ability. The influence of resistance of motion on cross-country ability of wheeled vehicle is shown by specific example.

Despite the significant progress achieved in recent years, the physical mechanisms underlying the origin of solar energetic particles (SEPs) are still a matter of debate. The complex nature of both particle acceleration and transport poses challenges to developing a universal picture of SEP events that encompasses both the low-energy (from tens of keV to a few hundreds of MeV) observations made by space-based instruments and the GeV particles detected by the worldwide network of neutron monitors in ground-level enhancements (GLEs). The high-precision data collected by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) satellite experiment offer a unique opportunity to study the SEP fluxes between $\sim$80 MeV and a few GeV, significantly improving the characterization of the most energetic events. In particular, PAMELA can measure for the first time with good accuracy the spectral features at moderate and high energies, providing important constraints for current SEP models. In addition, the PAMELA observations allow the relationship between low and high-energy particles to be investigated, enabling a clearer view of the SEP origin. No qualitative distinction between the spectral shapes of GLE, sub-GLE and non-GLE events is observed, suggesting that GLEs are not a separate class, but are the subset of a continuous distribution of SEP events that are more intense at high energies. While the spectral forms found are to be consistent with diffusive shock acceleration theory, which predicts spectral rollovers at high energies that are attributed to particles escaping the shock region during acceleration, further work is required to explore the relative influences of acceleration and transport processes on SEP spectra., Comment: 26 pages, 13 figures, 2 tables

The satellite-borne PAMELA experiment was launched on the 15th June 2006 from the Baikonur cosmodrome. Till January 2016 PAMELA has detected the charged component of cosmic-rays (CRs) over a wide e ...

New results on the galactic cosmic ray (GCR) short-term intensity variation associated with Forbush decrease and co-rotating interaction regions (CIRs) measured by the PAMELA instrument between November 2006 and March 2007 are presented. Most of the past measurements on Forbush decrease events were carried out with neutron monitor detector. This tecnique allows only indirect detection of the overall GCR intensity over an integrated energy range. For the first time, thanks to the unique features of the PAMELA magnetic spectrometer, the Forbush decrease associated with the December 13th coronal mass ejection (CME) was studied in a wide rigidity range (0.4-20 GV) and for different species of GCRs detected directly in space. Using GCR protons, the amplitude and the recovery time of the Forbush decrease were studied for ten rigidity interval with a temporal resolution of one day. For comparison the helium and the electron intensity over time were also studied. The temporal evolution of the helium and proton intensity was found in good agreement while the electrons show, on average, a faster recovery time. This was interpreted as a charge-sign dependence introduced by drift motion experienced by the low rigidity (

Precision measurements of the electron component of cosmic radiation provide important information about the origin and propagation of cosmic rays in the Galaxy not accessible from the study of cosmic-ray nuclear components due to their differing diffusion and energy-loss processes. However, when measured near Earth, the effects of propagation and modulation of Galactic cosmic rays in the heliosphere, particularly significant for energies up to at least 30 GeV, must be properly taken into account. In this paper the electron ( e − ) spectra measured by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics down to 70 MeV from 2006 July to 2009 December over six-month time intervals are presented. Fluxes are compared with a state-of-the-art three-dimensional model of solar modulation that reproduces the observations remarkably well.

An evolutionary-ecological analysis of homologous variations in cranial morphological structures (phenes) has been performed at the level of populations and subspecies exposed to technogenic, climatic, and landscape-geographic changes in the environment, as well as with ecological series of 46 species and infraspecific forms differing in ecological specialization within the family Cricetidae. On this basis, consistent manifestations of phenogenetic variation have been revealed. Species with the same ecological specialization show parallel directional changes in the frequencies of homologous phenes and their individual combinations. These changes apparently have adaptive significance and result from rearrangements in the ancestral epigenetic system. It is shown that similar ecological requirements imposed by the environment historically lead to unidirectional transformations of homologous morphological structures in different species, which may account for high incidence of homoplasy as well as for the parallel and, in part, directional evolution of closely related taxa with similar ecological specialization.

The cosmic-ray lithium and beryllium ($^{6}$Li, $^{7}$Li, $^{7}$Be, $^{9}$Be, $^{10}$Be) isotopic composition has been measured with the satellite-borne experiment PAMELA, which was launched into low-Earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. The rare lithium and beryllium isotopes in cosmic rays are believed to originate mainly from the interaction of high energy carbon, nitrogen and oxygen nuclei with the interstellar medium (ISM), but also on "tertiary" interactions in the ISM (i.e. produced by further fragmentation of secondary beryllium and boron). In this paper the isotopic ratios $^{7}$Li/$^{6}$Li and $^{7}$Be/($^{9}$Be + $^{10}$Be) measured between 150 and 1100 MeV/n using two different detector systems from July 2006 to September 2014 will be presented., 13 pages, 11 figures, accepted for publication in the Astrophysical Journal. arXiv admin note: text overlap with arXiv:1512.06535

On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. The apparatus comprises a time-of-flight system, a silicon-microstrip magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anti-coincidence system, a shower tail counter scintillator and a neutron detector. The scientific objectives addressed by the mission are the measurement of the antiprotons and positrons spectra in cosmic rays, the hunt for antinuclei as well as the determination of light nuclei fluxes from hydrogen to oxygen in a wide energy range and with very high statistics. In this paper the identification capability for light nuclei isotopes using two different detector systems (Time-of-Flight and multiple dE/dx measurements in the calorimeter) and preliminary results of the isotopic ratios will be presented.