28 research outputs found

    Agrochemical methods for reducing the translocation ability of heavy metals in sod-podzolic soil

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    Received: January 25th, 2022 ; Accepted: March 17th, 2022 ; Published: April 4th, 2022 ; Correspondence: [email protected] impact of technogenesis on the agricultural landscape contributes to the contamination of all its components by heavy metals. The main measure to protect the environment from the input of heavy metals is the prevention of pollution, which is achieved by improving the technology of agricultural production. The development of methods for the agrochemical rehabilitation of technogenically polluted soil, which ensure the receipt of environmentally safe crop products, is an urgent task. The paper presents the results of a lysimetric experiment on the study of the use of fertilizer systems for the purpose of remediation of heavy-metal-contaminated soddy-podzolic soil. It has been experimentally established that the translocation ability of heavy metals and, as a result, the accumulation of toxicants in grain and tilled crops is reduced when using an organomineral fertilizer system. All the studied fertilizer systems reduced the entry of dangerous ecotoxicants - lead and cadmium, into the infiltration water, and also caused the immobilization of Cu and Zn

    DIELECTRIC PROPERTIES OF POLYURETHANE NANOCOMPOSITES MODIFIED BY FULLERENE С60 AND NANODIAMONDS

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    The paper describes preparation of polyurethane composites infused with nano- and macro-sized carbonaceous fillerswith a different surface nature (with a hydrophobic surface-fullerene C60, fullerene soot, with a hydrophilic surface nano-diamonds, nano-diamond charge), with loading varying from 0.1 to 0.5 wt. % by in situ polymerization. The obtained nano-composites were measured by the method of dielectric spectroscopy to determine the nature of the influence of the surface origin and particle size on the structure and properties of the finished material. It was found that loading of fillers leads to the decrease in the process of α-relaxation activation energycompared to neat polyurethane (PU). It was revealed that the non-specific π-π interaction for nanosized fillers dominates over specific H-bonding, which can be related to the oxygen groups on the shells of nano-diamonds. The dielectric spectroscopy demonstrated that the glass transition temperature values of the nano-composites increase in comparison with neat PU, manifesting the so-called "antiplasticizating phenomenon", while composites with macro-sized filler exhibit a typical plasticizing effect for traditional fillers. The greatest value of the D parameter (fragility) corresponds to a sample with fullerene soot. The coincidence of activation energies of Maxwell-Wagner-Sillars polarization for different fillers means that the dimensions of the hard domains in the polymer have not changed

    Observation Of Very High Energy Cosmic-ray Families In Emulsion Chambers At High Mountain Altitudes (i)

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    Characteristics of cosmic-ray hadronic interactions in the 1015 - 1017 eV range are studied by observing a total of 429 cosmic-ray families of visible energy greater than 100 TeV found in emulsion chamber experiments at high mountain altitudes, Chacaltaya (5200 m above sea level) and the Pamirs (4300 m above sea level). Extensive comparisons were made with simulated families based on models so far proposed, concentrating on the relation between the observed family flux and the behaviour of high-energy showers in the families, hadronic and electromagnetic components. It is concluded that there must be global change in characteristics of hadronic interactions at around 1016 eV deviating from thise known in the accelerator energy range, specially in the forwardmost angular region of the collision. A detailed study of a new shower phenomenon of small-pT particle emissions, pT being of the order of 10 MeV/c, is carried out and its relation to the origin of huge "halo" phenomena associated with extremely high energy families is discussed as one of the possibilities. General characteristics of such super-families are surveyed. © 1992.3702365431Borisov, (1981) Nucl. Phys., 191 BBaybrina, (1984) Trudy FIAN 154, p. 1. , [in Russian], Nauka, MoscowLattes, Hadronic interactions of high energy cosmic-ray observed by emulsion chambers (1980) Physics Reports, 65, p. 151Hasegawa, ICR-Report-151-87-5 (1987) presented at FNAL CDF Seminar, , Inst. for Cosmic Ray Research, Univ. of TokyoCHACALTAYA Emulsion Chamber Experiment (1971) Progress of Theoretical Physics Supplement, 47, p. 1Yamashita, Ohsawa, Chinellato, (1984) Proc. 3rd Int. Symp. on Cosmic Rays and Particle Physics, p. 30. , Tokyo, 1984, Inst. for Cosmic Ray Research, Univ. of Tokyo(1984) Proc. 3rd Int. Symp. on Cosmic Rays and Particle Physics, p. 1. , Tokyo, 1984Baradzei, (1984) Proc. 3rd Int. Symp. on Cosmic Rays and Particle Physics, p. 136. , Tokyo, 1984Yamashita, (1985) J. Phys. Soc. Jpn., 54, p. 529Bolisov, (1984) Proc. 3rd Int. Symp. on Cosmic rays and Particle Physics, p. 248. , Tokyo, 1984, Inst. for Cosmic Ray Research, Univ. of TokyoTamada, Tomaszewski, (1988) Proc. 5th Int. Symp. on Very High Energy Cosmic-Ray Interactions, p. 324. , Lodz, 1988, Inst. for Cosmic Ray Research, Univ. of Tokyo, PolandHasegawa, (1989) ICR-Report-197-89-14, , Inst. for Cosmic Ray Research, Univ. of TokyoCHACALTAYA Emulsion Chamber Experiment (1971) Progress of Theoretical Physics Supplement, 47, p. 1Okamoto, Shibata, (1987) Nucl. Instrum. Methods, 257 A, p. 155Zhdanov, (1980) FIAN preprint no. 45, , Lebedev Physical Institute, MoscowSemba, Gross Features of Nuclear Interactions around 1015eV through Observation of Gamma Ray Families (1983) Progress of Theoretical Physics Supplement, 76, p. 111Nikolsky, (1975) Izv. Akad. Nauk. USSR Ser. Fis., 39, p. 1160Burner, Energy spectra of cosmic rays above 1 TeV per nucleon (1990) The Astrophysical Journal, 349, p. 25Takahashi, (1990) 6th Int. Symp. on Very High Energy Cosmic-ray Interactions, , Tarbes, FranceRen, (1988) Phys. Rev., 38 D, p. 1404Alner, The UA5 high energy simulation program (1987) Nuclear Physics B, 291 B, p. 445Bozzo, Measurement of the proton-antiproton total and elastic cross sections at the CERN SPS collider (1984) Physics Letters B, 147 B, p. 392Wrotniak, (1985) Proc. 19th Cosmic-Ray Conf. La Jolla, 1985, 6, p. 56. , NASA Conference Publication, Washington, D.CWrotniak, (1985) Proc. 19th Cosmic-Ray Conf. La Jolla, 1985, 6, p. 328. , NASA Conference Publication, Washington, D.CMukhamedshin, (1984) Trudy FIAN, 154, p. 142. , Nauka, Moscow, [in Russian]Dunaevsky, Pluta, Slavatinsky, (1988) Proc. 5th Int. Symp. on Very High Energy Cosmic-Ray Interactions, p. 143. , Lodz, 1988, Inst. of Physics, Univ. of Lodz, PolandKaidalov, Ter-Martirosyan, (1987) Proc. 20th Int. Cosmic-Ray Conf., Moscow, 1987, 5, p. 141. , Nauka, MoscowShabelsky, (1985) preprints LNPI-1113Shabelsky, (1986) preprints LNPI-1224, , Leningrad [in Russian]Hillas, (1979) Proc. 16th Int. Cosmic-Ray Conf., Kyoto, 6, p. 13. , Inst. for Cosmic Ray Research, Univ. of TokyoBorisov, (1987) Phys. Lett., 190 B, p. 226Hasegawa, Tamada, (1990) 6th Int. Symp. on Very High Energy Cosmic-Ray Interactions, , Tarbes, FranceSemba, Gross Features of Nuclear Interactions around 1015eV through Observation of Gamma Ray Families (1983) Progress of Theoretical Physics Supplement, p. 111Ren, (1988) Phys. Rev., 38 D, p. 1404Dynaevsky, Zimin, (1988) Proc. 5th Int. Symp. on Very High Energy Cosmic-Ray Interaction, p. 93. , Lodz, 1988, Inst. of Physics, Univ. of Lodz, PolandDynaevsky, (1990) Proc. 6th Int. Symp. on Very High Energy Cosmic-Ray Interactions, , Tarbes, France(1989) FIAN preprint no. 208, , Lebedev Physical Institute, Moscow(1990) Proc. 21st Int. Cosmic-Ray Conf., Adelaide, 8, p. 259. , Dept. Physics and Mathematical Physics, Univ. of Adelaide, AustraliaHasegawa, (1990) ICR-Report-216-90-9, , Inst. for Cosmic-Ray Research, Univ. of TokyoTamada, (1990) Proc. 21st Int. Cosmic-Ray Conf., Adelaide, 1990, 8. , Dept. Physics and Mathematical Physics, Univ. of Adelaide, AustraliaTamada, (1990) ICR-Report-216-90-9(1981) Proc. 17th Int. Cosmic-Ray Conf., Paris, 5, p. 291(1990) Proc. Int. Cosmic-Ray Conf., Adelaide, 1990, 8, p. 267. , Dept. Physics and Mathematical Physics, Univ. of Adelaide, Australia(1989) Inst. Nucl. Phys. 89-67/144, , preprint, Inst. Nucl. Phys., Moscow State UnivSmilnova, (1988) Proc. 5th Int. Sym. on Very High Energy Cosmic-Ray Interactions, p. 42. , Lodz, 1988, Inst. of Physics, Univ. of Lodz, PolandGoulianos, (1986) Proc. Workshop of Particle Simulation at High Energies, , University of Wisconsin, Madison, USAIvanenko, (1983) Proc. 18th Int. Cosmic-Ray Conf., Bangalore, 1983, 5, p. 274. , Tata Inst. Fundamental Research, Bombay, IndiaIvanenko, (1984) Proc. Int. Symp. on Cosmic-Rays and Particle Physics, p. 101. , Tokyo, 1984, Inst. for Cosmic Ray Research, Univ. of Tokyo(1988) 5th Int. Symp. on Very High Energy Cosmic-Ray Interactions, p. 180. , Lodz, 1988, Inst. of Physics, Univ. of Lodz, Poland(1990) Proc. 21st Int. Cosmic-Ray Conf., Adelaide, 1990, 8, p. 251. , Dept. Physics and Mathematical Physics, Univ. of Adelaide, Australia(1991) Izv. AN USSR No. 4, , to be publishedNikolsky, Shaulov, Cherdyntseva, (1990) FIAN preprint no. 140, , Lebedev Physical Institute, Moscow, [in Russian](1987) Proc. 20th Int. Cosmic-Ray Conf., Moscow, 1987, 5, p. 326. , Nauka, Mosco

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Сравнение методов модуляционной интерференционной микроскопии, ДНК-спектрометрии, ДНК-цитометрии и проточной цитофлюориметрии при оценке индуцированной фитогемагглютинином активности лимфоцитов крови человека

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    Rationale: The study of the structural particulars and functional state of immune cells and primarily lymphocytes is of great importance for both fundamental and clinical medicine. It requires the development of simple and reliable analytic methods that would allow for fast and effective real-time assessment of cell activity.Aim: To evaluate the effectiveness of the interference microscopy compared to DNA spectrometry, DNA cytometry, and flow cytometry with an internalized fluorescent label CFSE (carboxyfluorescein succinimidyl ester) in the assessment of PHA-induced proliferation of human blood lymphocytes.Materials and methods: Phytohemagglutinin (PHA)-induced proliferative activity of blood lymphocytes from 10  healthy volunteers was studied with various methodological strategies. Blast transformation of lymphocytes was induced by their incubation for 5 days with PHA 5 μg/mL. The cell proliferative activity was assessed as follows: 1) by DNA spectrometry at 260/280 nm using Tecan Infinite 200  Pro with a  specialized NanoQuant Plate™; 2)  by cytophotometry followed by cell distribution analysis assessing deoxyribonucleic acid (DNA) content after staining with Felgen's dye with an imaging system based on an Olympus BX41 light microscope with a ProgRes CF camera; 3) by flow cytometry using an internalized fluorescent label CFSE; the analysis was performed with a BD FACS Calibur flow cytometer; 4) by measurement of the lymphocyte interference profile with a  modulation interference microscope MIM-340 (Schwabe, Russia). The functional activity of the nucleus (FAN) was determined and used as a criterion for assessment of the lymphocyte functional state.Results: Incubation of lymphocytes with PHA led to an increase in the linear size by 22.2±2.8%, a  decrease in phase height by 46.3±4.7% (p=0.019), and an increase in FAN by 75.9±9.4%, vs control (p=0.046). As measured by isolated DNA spectroscopy, PHA stimulation of lymphocytes was associated with an increase in the amount of DNA by  55% vs baseline (409.8±22.3  ng/μL and 264.3±25.0  ng/μL, respectively, p=0.049). Felgen's reaction revealed that the proportion of nuclei containing more than 2n DNA was 2% in the control cells and 14.8% in the PHA-activated lymphocytes, with a  difference between the groups of 12.8%. CFSE staining with subsequent incubation and assessment by flow cytofluorimetry demonstrated an increase in the percentage of proliferating cells from 1.68±0.9% in the control to 55.56±5.6% (p=0.00068) in the mitogen-stimulated sample.Conclusion: Modulation interference microscopy does not require the sample preparation and demonstrated comparable and even higher effectiveness compared to conventional methods for assessment of lymphocyte activity. At the same time, it allows for evaluation of the lymphocyte functional state in real time in the process of cultivation. This opens ample opportunities for evaluation immune cells for research and diagnostic purposes. Актуальность. Исследование структурных особенностей и  функционального состояния клеток иммунной системы и  прежде всего лимфоцитов имеет большое значение как для фундаментальной, так и  для клинической медицины. Необходима разработка простых и надежных методов анализа, позволяющих быстро и  эффективно оценивать активность клеток в реальном времени.Цель  – оценить эффективность использования метода интерференционной микроскопии в  сравнении с  классическими методами (ДНК-спектрометрия, ДНК-цитометрия и  проточная цитофлюориметрия с  использованием интернализованной флюоресцентной метки CFSE (carboxyfluorescein succinimidyl ester)) при оценке индуцированной фитогемагглютинином (ФГА) пролиферации лимфоцитов крови человека.Материал и  методы. ФГА-индуцированную пролиферативную активность лимфоцитов крови 10  здоровых добровольцев оценивали с  использованием различных методических подходов. Бласт-трансформацию лимфоцитов вызывали их инкубацией в  течение 5  суток в присутствии 5 мкг/мл ФГА. Пролиферативную активность клеток оценивали 1) методом ДНКметрии  – в  специализированном планшете Tecan NanoQuant PlateTM путем измерения оптической плотности, на планшет-ридере Infinite 200 Pro; 2) методом цитофотометрии с последующим анализом распределения клеток по содержанию дезоксирибонуклеиновой кислоты (ДНК) после окраски красителем Фельгена с помощью системы визуализации на базе светового микроскопа Olympus BX41, видеокамеры ProgRes CF; 3) методом проточной цитометрии с  использованием интернализованной флюоресцентной метки CFSE, анализ проводили на проточном цитометре BD FACS Calibur; 4) измерением параметров интерференционного профиля лимфоцитов при помощи модуляционного интерференционного микроскопа МИМ-340 («Швабе», Россия). В  качестве критерия оценки функционального состояния лимфоцитов определяли функциональную активность ядра (англ. functional activity of the nucleus, FAN).Результаты. Инкубация лимфоцитов с  ФГА приводила к  увеличению линейного размера клеток на 22,2±2,8%  мкм, уменьшению фазовой высоты на 46,3±4,7%  нм ( p=0,019) и  увеличению FAN на 75,9±9,4% по сравнению с контролем (p=0,046). По данным спектроскопии выделенной ДНК, стимуляция лимфоцитов ФГА сопровождалась увеличением количества ДНК на 55% по сравнению с исходным значением (до 409,8±22,3 против 264,3±25,0 нг/мкл, p=0,049). Реакция Фельгена выявила, что в контрольной выборке ядра, содержащие ДНК в  количестве, превышающем 2n, составляют 2%, а в выборке активированных ФГА лимфоцитов – 14,8% с разницей между группами 12,8%. Окраска лимфоцитов CFSE с последующей инкубацией проточной цитофлюориметрией культивированных клеток показала повышение процента пролиферирующих клеток с 1,68±0,9% в контроле до 55,56±5,6%  (p=0,00068) под влиянием митогена.Заключение. По сравнению с  классическими методами оценки активности лимфоцитов метод модуляционной интерференционной микроскопии не требует пробоподготовки, показывает сопоставимую и  даже большую эффективность, при этом позволяет изучать функциональное состояние лимфоцитов в  реальном времени в динамике культивирования. Это открывает широкие возможности для оценки клеток иммунной системы в исследовательских и диагностических целях

    Adaptive infrastructure and technological opportunities for the development of the digital enterprise economy

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    The development of digital enterprises takes place in constantly changing conditions, requiring the use of adequate infrastructure and technological capabilities to adapt to change, withstanding competition in domestic and foreign markets. The priority areas in the implementation of infrastructure and technological opportunities for the development of digital enterprises are updated strategic management technologies, non-standard mechanisms for increasing economic activity of the population, better digital financial instruments, as well as effective cybersecurity and economic adaptation systems required in the new economic conditions.Развитие цифровых предприятий происходит в постоянно меняющихся условиях, требующих использования соответствующей инфраструктуры и технологических возможностей для адаптации к изменениям, выдерживая конкуренцию на внутреннем и внешнем рынках. Приоритетными направлениями в реализации инфраструктуры и технологических возможностей для развития цифровых предприятий являются обновленные технологии стратегического управления, нестандартные механизмы повышения экономической активности населения, более совершенные цифровые финансовые инструменты, а также необходимые эффективные системы кибербезопасности и экономической адаптации в новых экономических условиях
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