Role of demyelination in the persistence of neurological and mental impairments after COVID-19

Long-term neurological and mental complications of COVID-19, the so-called post-COVID syndrome or long COVID, affect the quality of life. The most persistent manifestations of long COVID include fatigue, anosmia/hyposmia, insomnia, depression/anxiety, and memory/attention deficits. The physiological basis of neurological and psychiatric disorders is still poorly understood. This review summarizes the current knowledge of neurological sequelae in post-COVID patients and discusses brain demyelination as a possible mechanism of these complications with a focus on neuroimaging findings. Numerous reviews, experimental and theoretical studies consider brain demyelination as one of the mechanisms of the central neural system impairment. Several factors might cause demyelination, such as inflammation, direct effect of the virus on oligodendrocytes, and cerebrovascular disorders, inducing myelin damage. There is a contradiction between the solid fundamental basis underlying demyelination as the mechanism of the neurological injuries and relatively little published clinical evidence related to demyelination in COVID-19 patients. The reason for this probably lies in the fact that most clinical studies used conventional MRI techniques, which can detect only large, clearly visible demyelinating lesions. A very limited number of studies use specific methods for myelin quantification detected changes in the white matter tracts 3 and 10 months after the acute phase of COVID-19. Future research applying quantitative MRI assessment of myelin in combination with neurological and psychological studies will help in understanding the mechanisms of post-COVID complications associated with demyelinatio

Синергизм и синергические эффекты в технологии переработки полимеров

The work deals with the terms synergism and synergic systems evolution. The analysis of literatre sources in which the results of synergic effects study in polymer`s technology are presented, is carried out. Modern approaches to estimate synergic effects, identification, analysis and synergic systems forming are reviewed, and that allows scientifically-based solving the practical receipt-biilding tasks of polymer materials and their processing technological processes parameters choice.В работе отражена эволюция терминов синергизм, синергический эффект, синергическая система. Проведен анализ литературных источников, в которых представлены результаты изучения эффектов синергизма в технологии переработки полимеров. Рассмотрены современные подходы к оценке эффектов синергизма, идентификации, анализу и формированию синергических систем, что позволяет научно обоснованно решать практические задачи рецептуростроения полимерных материалов и выбора параметров технологических процессов их переработки

Structuring ampelographic collections by phenotypic characteristics and comparing the reaction of grape varieties to climate change

Modern climate changes task breeders to adapt viticulture to the new natural resource potential of the regions. A necessary condition is the assessment and analysis of current trends in changing the characteristics of contrasting groups of varieties. The aim of the study is to identify homogeneous groups  of varieties of an ampelographic collection and to compare the rates of reaction  of their agrobiological parameters to climate changes. Material for the study consists of observations of 21 agrobiological characteristics of 109 grape varieties from the Don ampelographic collection named after Ya.I. Potapenko (Novocherkassk) with an observation period from 10 to 36 years in 1981–2017. The sample included  Vitis vinifera L. varieties and the V. vinifera L. × V. labrusca L. and V. vinifera L. × V. amurensis Rupr. interspecific hybrids, and hybrids from crosses between V. vinifera L. and several American species. Homogeneous groups  of characteristics and varieties are identified by principal component analysis (PCA) and analysis of variance (ANOVA) methods. Trends in changing the agrobiological characteristics of the varieties and groups  of varieties are calculated.  PCA revealed  that the main differentiating factor of the studied fragment of the ampelographic collection is the size of the bunch; the second, the yield; the third, the time of ripening. The values of the factors are contrasting in varieties of different  directions  of use and taxonomic origin, which was confirmed  by ANOVA. The groups  of the V. vinifera × V. labrusca and V. vinifera × V. amurensis hybrids do not differ significantly from each  other  in most  indicators,  exceeding V. vinifera varieties in the  number of elements of productivity, winter hardiness and yield. Complex hybrids with American species have an intermediate position  between these  groups exceeding all groups  in bunch  weight.  All groups  of cultivars show trends  towards  a reduction in productive period,  an increase  in the mass of bunch  and yield, sugar content and a decrease in acidity. The V. vinifera × V. labrusca hybrids are distinguished by the highest growth  rate of the bunch  mass caused  by a reduction in the duration of active growth  and a decrease in the percentage of fruit-bearing shoots.  A higher  reduction rate of the production period  and a decrease in acidity were observed in later varieties. Regression analysis showed that the acceleration of the ripening of grapes is largely due to rising temperatures

Физическое представление и расчет начала кипения в пульсационной тепловой трубе

Отримано формулу для розрахунку теплового потоку, який забезпечує початок кипіння теплоносія в пульсаційній тепловій трубі (ПТТ), і визначено нижню границю ефективної роботи ПТТ. Показано, що основними факторами, що впливають на величину цього теплового потоку, є рушійний капілярний напір та швидкість руху парової бульбашки. Формулу для визначення теплового потоку було отримано для замкнених ПТТ, виготовлених з міді, з водою як теплоносій. Інформація про величину теплового потоку є необхідною для подальшого проектування систем охолодження різноманітних теплонавантажених елементів, чутливих до перегріву, наприклад світлодіодів перспективних освітлювальних пристроїв.LED development is accompanied by the need to ensure a constructive solution for the thermal conditions problem. For this purpose one can use pulsating heat pipes (PHP), that operate more efficiently after the start of heat carrier boiling. This article describes the physical representation and formula that allows determining the boiling point, which is a lower bound of the PHP effective operating range. It is shown that the main factors influencing the required heat flow are driving capillary pressure and velocity of the vapor bubble. The formula was obtained for the closed PHP made of the copper with water as a heat carrier. Information about this heat flux can be used for further design of cooling systems for heat-sensitive elements, such as LED for promising lighting devices.Получена формула для расчета теплового потока, обеспечивающего начало кипения теплоносителя в пульсационной тепловой трубе (ПТТ), т. е. определяющего нижнюю границу эффективной работы ПТТ. Показано, что основными факторами, влияющими на искомую величину теплового потока, являются движущий капиллярный напор и скорость движения парового пузырька. Формула для определения теплового потока была получена для замкнутых ПТТ, изготовленных из меди, с водой в качестве теплоносителя. Информация о величине теплового потока необходима для дальнейшего проектирования систем охлаждения различных теплонагруженных элементов, чувствительных к перегреву, например светодиодов перспективных осветительных устройств

Characterization of the core bacteriobiome in the rhizosphere of greenhouse vegetables: taxonomic diversity and putative functions

The aim of the study. The aim was to profile 16S rRNA gene diversity and to assess functional potential of bacterial assemblages in the rhizosphere of some unconventional vegetables grown in protected greenhouse conditions in West Siberia. Location and time of the study. Novosibirsk, Russia, 2016. Methodology. At the end of the growing season in the middle of September the rhizosphere soil was collected from the plants of wax gourd (Benincasa hispida), bitter melon (Momordica charantia), kiwano (Cucumis metuliferus) and cowpea (Vigna unguiculata) grown on peat-based substrate in a polyethylene-protected greenhouse that has been in operation for more than 40 years. The metagenomic DNA was extracted and amplified with V3-V4 primers for 16S rRNA genes, and the amplicons sequenced with Illumina MiSeq. The obtained OTUs tables were used to predict putative functions by running through the FAPROTAX database. Main results. The rhizosphere bacteriobiome was dominated by Proteobacteria (32±11% of the total number of sequence reads), Acidobacteria (23±7%) and Actinobacteria (18±3%) phyla, together accounting for about three quarters of the rhizosphere bacteriobiome. In total 20 bacterial phyla were found. The rhizosphere bacteriobiome was surprisingly diverse with Shannon index ranging 7.0–7.5. The number of the observed operational taxonomic units (OTUs) per sample was very high, ranging 4,500–4,900, and the potential number of OTUs estimated as 5,100–5,700; all those OTUs were evenly and equitably represented in the bacteriobiome, and dominance indices (Simpson dominance and Berger-Parker) were very low. The main dominant OTU represented Bradyrhizobiaceae family and accounted for just 1% on average. Overall the study identified 27 OTUs belonging to the Bradyrhizobiaceae family, but only four of them were ascribed to nitrogen fixation by FAPROTAX. Function prediction by FAPROTAX also suggested that bacteriobiome had a marked potential for the carbon cycle, denitrification, aromatic compound and plant polymer degradation, but no plant pathogens. The biggest difference in rhizosphere bacteriobiome diversity was observed between the bitter melon and the other three vegetable crops: bitter melon had much increased abundance of Arthrobacter and Sphingomonas as compared with wax gourd, kiwano and cowpea, and increased number of bacterial species associated with aromatic compounds degradation. Conclusion. Based on the finding that the studied rhizosphere bacteriobiomes were very diverse, we conclude that the crops were able to recruit diverse microbiota from the peat-based soil substrate, which, in its turn, means that diverse soil substrate microbiota has been sustained over several decades of the greenhouse operation. All crops apparently shaped distinct bacteriobiomes in their rhizosphere, which ideally should be included into studies of plant-associated bacterial diversity profiles for breeding and sustainable production.The aim of the study. The aim was to profile 16S rRNA gene diversity and to assess functional potential of bacterial assemblages in the rhizosphere of some unconventional vegetables grown in protected greenhouse conditions in West Siberia. Location and time of the study. Novosibirsk, Russia, 2016. Methodology. At the end of the growing season in the middle of September the rhizosphere soil was collected from the plants of wax gourd (Benincasa hispida), bitter melon (Momordica charantia), kiwano (Cucumis metuliferus) and cowpea (Vigna unguiculata) grown on peat-based substrate in a polyethylene-protected greenhouse that has been in operation for more than 40 years. The metagenomic DNA was extracted and amplified with V3-V4 primers for 16S rRNA genes, and the amplicons sequenced with Illumina MiSeq. The obtained OTUs tables were used to predict putative functions by running through the FAPROTAX database. Main results. The rhizosphere bacteriobiome was dominated by Proteobacteria (32±11% of the total number of sequence reads), Acidobacteria (23±7%) and Actinobacteria (18±3%) phyla, together accounting for about three quarters of the rhizosphere bacteriobiome. In total 20 bacterial phyla were found. The rhizosphere bacteriobiome was surprisingly diverse with Shannon index ranging 7.0–7.5. The number of the observed operational taxonomic units (OTUs) per sample was very high, ranging 4,500–4,900, and the potential number of OTUs estimated as 5,100–5,700; all those OTUs were evenly and equitably represented in the bacteriobiome, and dominance indices (Simpson dominance and Berger-Parker) were very low. The main dominant OTU represented Bradyrhizobiaceae family and accounted for just 1% on average. Overall the study identified 27 OTUs belonging to the Bradyrhizobiaceae family, but only four of them were ascribed to nitrogen fixation by FAPROTAX. Function prediction by FAPROTAX also suggested that bacteriobiome had a marked potential for the carbon cycle, denitrification, aromatic compound and plant polymer degradation, but no plant pathogens. The biggest difference in rhizosphere bacteriobiome diversity was observed between the bitter melon and the other three vegetable crops: bitter melon had much increased abundance of Arthrobacter and Sphingomonas as compared with wax gourd, kiwano and cowpea, and increased number of bacterial species associated with aromatic compounds degradation. Conclusion. Based on the finding that the studied rhizosphere bacteriobiomes were very diverse, we conclude that the crops were able to recruit diverse microbiota from the peat-based soil substrate, which, in its turn, means that diverse soil substrate microbiota has been sustained over several decades of the greenhouse operation. All crops apparently shaped distinct bacteriobiomes in their rhizosphere, which ideally should be included into studies of plant-associated bacterial diversity profiles for breeding and sustainable production

ПАРАЗИТОЛОГИЧЕСКИЙ КОНТРОЛЬ ОБЪЕКТОВ СЕЛЬСКОХОЗЯЙСТВЕННОГО РЫБОВОДСТВА

Objective of research: to perform the parasitological monitoring we have to study the parasite fauna in fishes from different fish farm factories, calculate the index of similarity, estimate the influence of abiotic and biotic factors on the ecosystem of fish-breeding reservoirs. Materials and methods: parasitological monitoring of factory fish farms was conducted by the method of complete and incomplete parasitological examination taking into account the data obtained from various fish-breeding reservoirs. Results and discussion: the parasite fauna of cyprinid fishes is represented by 56 species, carriage of causative agents of parasitic diseases in fishes is detected. Index of similarity of parasite fauna in carps has been studied and typification of agricultural reservoirs carried out. Index of  similarity between the parasite fauna in carp and herbivorous fish was 22–33 %, carp and rough fish - 18–30,7 %. Influence of abiotic (oxidability, reduction of oxygen and nitrogen ammonia concentration, mineralization) and biotic – anthropogenic factors (violation of processing technologies, veterinary and sanitary rules of fish transport and fish farming operations) on fish infestation with parasites was studied. The role of parasitological monitoring in prevention and elimination of fish diseases was shown.Цель исследования – с целью паразитологического контроля изучить паразитофауну рыб на различных объектах сельскохозяйственного рыбоводства, рассчитать индекс общности, оценить влияние абиотических и биотических факторов на экосистему рыбоводного водоема. Материалы и методы. Паразитологический контроль объектов рыбоводства проводили методом полного и неполного паразитологического исследования, учитывая многолетние данные, полученные в условиях водоемов разных зон рыбоводства. Результаты и обсуждение. Паразитофауна карповых рыб представлена 56 видами, выявлено носительство возбудителей смешанных паразитарных болезней рыб. Изучен индекс общности паразитофауны карпа и проведено типирование сельскохозяйственных водоёмов. Индекс общности паразитофауны карпа с растительноядными рыбами составил 22–33 %, карпа и сорных рыб – 18–30,7 %. Изучено влияние абиотических (окисляемости, снижения кислорода, аммонийного азота и минерализации) и биотических – антропогенных факторов (нарушение технологий, ветеринарно-санитарных правил при перевозках рыб и эксплуатации хозяйств) на зараженность рыб паразитами. Показана роль паразитологического контроля в профилактике и ликвидации болезней рыб

ОЗДОРОВЛЕНИЕ РЫБОВОДНОГО ХОЗЯЙСТВА ОТ БОЛЕЗНЕЙ ОСУШЕНИЕМ ПРУДОВ С ИСПОЛЬЗОВАНИЕМ РЫБОСЕВОБОРОТА

Objective of research: to present the actuality and novelty of application of fish and grass “rotation” because this allows to reveal new data on pond drainage planning which is the most effective in sanitation of the fish farm.Materials and methods: To determine the most effective cycle for the summer drying of ponds, we studied ecological and epizootological features of fishing ponds, which had been used after drying within 1 and 5 years. As research object served 8 fish ponds: 4 drained ponds under crop (40 ha), 4 – overflowed (40 ha) and filled with one-year carps (2,5-З thousand ind./ha) and silver carps (1,2-1,4 thousand ind./ha).Results and discussion: The results of comparative research on anti-epizootic efficacy of pond drying at different periodicity of 1 and 5 years with the use of fish and grass “rotation” are provided. Data on decreased invasion of fishes (carp, silver carp) by parasites, absence of causative agents of infection, improved blood indicators, increased fish production at annual pond drying (with the use of fish and grass “rotation”) compared with the pond drying of 5 year periodicity are presented. Advantages of economic efficacy of the annual frequency of pond drying are confirmed: twice increased commercial fish production; reduced expenses for purchase of food (own barley and wheat production), drugs, disinfectants, fertilizers that allow increasing economic revenue and making profit.Цель исследований вызвана актуальностью и новизной применения рыбосевооборота, так как это позволяет выявить новые знания о наиболее эффективной для оздоровления хозяйства схемы осушения прудов.Материалы и методы. Для выявления наиболее эффективной периодичности летования прудов было изучено эколого-эпизоотическое состояние нагульных прудов, эксплуатируемых после осушения в течение 1 года и 5 лет. Объектами изучения были 8 нагульных прудов: четыре осушенных и засеянных сельскохозяйственными культурами (400 га), четыре залитых (400га) и зарыбленных годовиками карпа (2,5-Зтыс.шт./га) и толстолобика (1,2-1,4тыс.шт/га).Результаты и обсуждение. Приведены результаты сравнительного изучения противоэпизоотической эффективности разной периодичности осушения прудов (через 1 год и 5 лет) с использованием рыбосевооборота. Показано снижение заражённости рыб (карпа, толстолобика) паразитами, отсутствие возбудителей инфекций, улучшение показателей крови, увеличение рыбопродуктивности при годичной периодичности осушения прудов (с использованием рыбосевооборота) по сравнению с периодичностью осушения в 5 лет. Подтверждены преимущества экономической эффективности годичной периодичности осушения прудов: увеличилось в 2 раза производство товарной рыбы, уменьшились затраты на приобретение кормов (за счет собственного кормопроизводства зерновых - ячменя, пшеницы), лечебных препаратов, дезинфицирующих средств, удобрений, что увеличило выручку в хозяйстве и позволило получать прибыль

The Use of Multicolor Flow Cytofluorometry in White Blood Cell Differential: HematoFlow Conception

Aim. To develop reference intervals for white blood cell subpopulations in peripheral blood using Cytomics FC500 flow cytometer and CytoDiffTM reagent (Beckman Coulter). Materials & Methods. The trial included the analysis of blood samples of healthy donors (n = 315) using Cytomics FC500 flow cytometer and CytoDiffTM reagent cocktail composed of 6 antibodies in 5 colors (CD36-FITC, CD2-PE, CD294-PE, CD19-ECD, CD16-Cy5, CD45-Cy7) and enabling to count 17 cell populations. Results. The data obtained by means of multicolor flow cytofluorometry included the reference values of white blood cell populations in peripheral blood. In 1 first-time donor a lymphoproliferative disease was detected. It was subsequently confirmed by immunophenotyping; B-cell chronic lymphocytic leukemia was diagnosed. Conclusion. Multicolor flow cytofluorometry using CytoDiffTM is considered to be a new step toward an improved WBC differential evaluation aimed mainly at reducing the volume of blood smear analysis using light microscopy at large laboratories, enhancing objectivity, precision and reproducibility of results. WBC differential extended with the count of lymphocyte and monocyte subpopulations can be regarded as modern donor blood screening to detect changes in the pattern of lymphocyte subpopulations as grounds for further examination of donors

О рецептуростроении клеев с постоянной «липкостью» на основе бутадиен-нитрильных каучуков

The optimal set of the properties of elastomeric glues can be achieved by the right ratio of components. The combined influence of resins, plasticizers and agents of tackiness on the properties of adhesive compositions was studied.Оптимального комплекса свойств эластомерных клеев можно достигнуть благодаря правильному соотношению компонентов. Изучено совместное влияние на свойства клеевых композиций смол , пластификатора и агента липкости