60 research outputs found
КОМБИНИРОВАННЫЙ МЕТОД СПЕКТРАЛЬНОГО ОЦЕНИВАНИЯ ПРИ ПОЛУЧЕНИИ СВЕРХРАЗРЕШЕНИЯ ПО ЧАСТОТЕ
Evaluating of the power spectral density (SPM) of signal are usually performed through procedures using classical methods spectral analysis based on the discrete Fourier transform. This approach to spectral analysis is computationally efficient and provides acceptable results. However, in spite of these advantages, a classical method has a number of fundamental limitations. The most important of these is the limitation of the frequency resolution. For the solution of a problem of increase in the frequency resolution, in practice such methods as MUSIC, EV, Berg, MD assessment etc. In article presents classical methods of estimation power spectrum density, method the minimum error variance (MD estimate) and developed combined method.Оценивание спектральной плотности мощности (СПМ) сигнала обычно выполняется с помощью классических методов спектрального анализа, основанных на дискретном преобразования Фурье. Такой подход к спектральному анализу эффективен в вычислительном отношении и обеспечивает получение приемлемых результатов. Однако, несмотря на указанные достоинства, классическим методам присущ ряд принципиальных ограничений. Наиболее важное из них – это ограничение разрешающей способности. Для решения задачи повышения частотного разрешения на практике используются такие методы, как MUSIC, EV, Берга, МД-оценка и т. д. [1]. В статье рассматриваются классические методы оценки спектральной плотности мощности, метод минимума дисперсии ошибки (МД-оценка) и разработанный комбинированный метод
СРАВНИТЕЛЬНЫЙ АНАЛИЗ РАЗРЕШАЮЩЕЙ СПОСОБНОСТИ АЛГОРИТМОВ СПЕКТРАЛЬНОГО ОЦЕНИВАНИЯ
The classical methods of evaluating the energy spectra of discretized deterministic and stochastic processes are generally based on the use of procedures that use the fast Fourier transformation (FFT). The classical approach to spectral analysis is effective in respect of computational and provides asymptotically reliable estimates for very extensive classing signals, satisfying the hypothesis of stationary, ergodicity and limits the large sample volume. Limitations of classical spectral estimates especially apparent when analyzing short data records. However, just such a situation is typical for most practical applications, because many processes have measurable short duration or rapidly changing spectra in time.Классические методы оценки спектров дискретизованных детерминированных и случайных процессов обычно основаны на применении процедур, использующих быстрое преобразование Фурье (БПФ). Классический подход к спектральному анализу эффективен в вычислительном отношении и обеспечивает получение асимптотически достоверных оценок для весьма обширного класса сигналов, удовлетворяющих гипотезе стационарности, эргодичности и ограничению выборки большого объема. Ограничения классических спектральных оценок особенно сильно проявляются при анализе коротких записей данных. Однако именно такая ситуация является типичной для большинства практических приложений, поскольку многие измеряемые процессы обладают малой длительностью или же быстро изменяющимися во времени спектрами
Study of the curvature of forging from titanium alloy in the process of forging
В роботі розглянуто формозмінення титанового сплаву ВТ-6 шляхом математичного моделювання при ковальської витяжці за різними схемами кування в комбінованих бойках. Основною метою дослідження була оптимізація отримання прямолінійності поковки при реалізації протяжки за різними схемами для можливості автоматизації режимів деформування і зниження необхідності подальшого правлення. Результатом роботи є отримання даних про викривлення поковки щодо зони деформації в межбойковом просторі та аналіз причин, що його викликають.Purpose. The main aim of the study is to optimize the straightness of obtaining forgings with the implementation of the drawing process by different schemes for possible automatization modes of deformation and reduce the need for further edits of forgings. Design/methodology/approach. The main research method is a computer simulation of forging process of titanium billets. To determine the degree of curvature of the forgings at the end of the process has been developed a method which allows to determine the deviation of the Central axis of the billet from the normal. Findings. As a result of this work were made the conclusions about the schemes of forging of forgings on the degree of their curvature. Developed and improved forging scheme that allows to achieve the minimal curvature of the billet during the forging process, and also to achieve the minimal uneven distribution of deformations in the metal. Originality/value. The results of this work are applicable in the industrial production of forgings made from titanium alloys and can be the basis for writing computer programs for automatization of the forging process on the automated forging complexes.В работе рассмотрено формоизменение титанового сплава ВТ-6 путем математического моделирования при кузнечной вытяжке по разным схемам ковки в комбинированных бойках. Основной целью исследования ставилась задача оптимизация получения прямолинейности поковки при реализации протяжки по разным схемам для возможности автоматизации режимов деформирования и снижения необходимости последующей правки. Результатом работы является получение данных об искривлении поковки относительно оси зоны деформации в межбойковом пространстве и анализ причин его вызывающих
Approaches of Russian oil companies to optimal capital structure
Oil companies play a vital role in Russian economy. Demand for hydrocarbon products will be increasing for the nearest decades simultaneously with the population growth and social needs. Change of raw-material orientation of Russian economy and the transition to the innovative way of the development do not exclude the development of oil industry in future. Moreover, society believes that this sector must bring the Russian economy on to the road of innovative development due to neo-industrialization. To achieve this, the government power as well as capital management of companies are required. To make their optimal capital structure, it is necessary to minimize the capital cost, decrease definite risks under existing limits, and maximize profitability. The capital structure analysis of Russian and foreign oil companies shows different approaches, reasons, as well as conditions and, consequently, equity capital and debt capital relationship and their cost, which demands the effective capital management strategy
CHANGE IN CONTENT OF GLYCOPROTEINS ON THE SURFACE OF ENDOTHELIAL CELL CULTURE EA.HY 926 AND INTIMA OF INTERNAL CAROTID ARTERIES UNDER THE INFLUENCE OF MAGNESIUM OROTATE
Aim. To study changes in the glycoproteins content in the glycocalyx of endothelial cells under the influence of magnesium orotate.Material and methods. Endotheliocytes of cell culture EA.hy 926 were examined before and after addition of the magnesium orotate to the culture medium. Intimal endothelium of internal carotid arteries, fragments of which were obtained by sequential execution of bilateral resection of the arteries before and after course of treatment with magnesium orotate was also investigated. Anthony’ method (1931), designed for the study of glycoproteins in the bacteria capsule and adapted by L.V. Didenko (2013) for eukaryotes was used to detect glycoproteins. The scanning electron microscopy with simultaneous x-ray microanalysis was applied.Results. Total number of Cu2+-signals per one scanning field in the mapping of samples for Cu2+ as the indirect index of proteoglycan content in EA.hy 926 endothelial cell culture before incubation with magnesium orotate was 6928±124, and after incubation with magnesium orotate – 7592±131. Number of Cu2+-signals on the surface of the internal carotid artery intima before treatment with magnesium orotate was 5015±407, and after treatment – 6100±152 per one scanning field.Conclusion. A significant increase in the content of glycoproteins on the surface of EA.hy926 endothelial cell culture (+10%) and internal carotid artery intima (+22%) under the influence of magnesium orotate was found
Financial Aspects of Technological Concept for Energy Efficiency Enhancement during Stripper Wells Development in Tomsk Region
The issue of operating costs cutting in terms of falling oil prices on the world market actualizes the challenge to find technological solutions to reduce electricity consumption during well operation. This is especially important for stripped-wells of small deposits in Tomsk region. The correlation analysis between the cost of oil production, electricity, heat and fuel consumption during the extraction of one ton of oil allowed the authors to focus on the financial aspect of such technological solutions like periodic well operation in the Shinginskoye field as well as to recommend the application of this method at the other fields in Tomsk region
Novel allosteric mechanism of p53 activation by small molecules for targeted anticancer therapy
Given the immense significance of p53 restoration for anti-cancer therapy and that p53-activating molecules are in clinical trials, elucidation of the mechanisms of action of p53-activating molecules is of the utmost importance. Here we report a discovery of a novel allosteric modulation of p53 by small molecules, which is an unexpected turn in the p53 story. We identified a structural element involved in allosteric regulation of p53, whose targeting by small molecules RITA, PpIX and licofelone blocks the binding of two p53 inhibitors, MDM2 and MDMX, thereby restoring p53 function. Deletion and mutation analysis followed by molecular modeling and its thorough validation, identified the key p53 residues S33 and S37 targeted by RITA and PpIX. We propose that the binding of small molecules to the identified site in p53 induces a conformational trap preventing p53 from the interaction with MDM2 and MDMX. These results point to a high potential of allosteric activators as targeted drugs. Our study provides a basis for the development of therapeutics with a novel mechanism of action, thus extending the p53 pharmacopeia
A CRISPR Dropout Screen Identifies Genetic Vulnerabilities and Therapeutic Targets in Acute Myeloid Leukemia
Acute myeloid leukemia (AML) is an aggressive cancer with a poor prognosis, for which mainstream treatments have not changed for decades. To identify additional therapeutic targets in AML, we optimize a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening platform and use it to identify genetic vulnerabilities in AML cells. We identify 492 AML-specific cell-essential genes, including several established therapeutic targets such as , , and , and many other genes including clinically actionable candidates. We validate selected genes using genetic and pharmacological inhibition, and chose as a candidate for downstream study. inhibition demonstrated anti-AML activity by inducing myeloid differentiation and apoptosis, and suppressed the growth of primary human AMLs of diverse genotypes while sparing normal hemopoietic stem-progenitor cells. Our results propose that KAT2A inhibition should be investigated as a therapeutic strategy in AML and provide a large number of genetic vulnerabilities of this leukemia that can be pursued in downstream studies.This work was funded by the Kay Kendall Leukaemia Fund (KKLF) and the Wellcome Trust (WT098051). G.S.V. is funded by a Wellcome Trust Senior Fellowship in Clinical Science (WT095663MA) and work in his laboratory is funded by Bloodwise. C.P. is funded by a Kay Kendall Leukaemia Fund Intermediate Fellowship (KKL888)
A high content screen for mucin-1-reducing compounds identifies fostamatinib as a candidate for rapid repurposing for acute lung injury
Drug repurposing has the advantage of identifying potential treatments on a shortened timescale. In response to the pandemic spread of SARS-CoV-2, we took advantage of a high-content screen of 3,713 compounds at different stages of clinical development to identify FDA-approved compounds that reduce mucin-1 (MUC1) protein abundance. Elevated MUC1 levels predict the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and correlate with poor clinical outcomes. Our screen identifies fostamatinib (R788), an inhibitor of spleen tyrosine kinase (SYK) approved for the treatment of chronic immune thrombocytopenia, as a repurposing candidate for the treatment of ALI. In vivo, fostamatinib reduces MUC1 abundance in lung epithelial cells in a mouse model of ALI. In vitro, SYK inhibition by the active metabolite R406 promotes MUC1 removal from the cell surface. Our work suggests fostamatinib as a repurposing drug candidate for ALI
Study of an Experimental Prototype of the DTeT Detector in the Proton Beam of a Radiotherapeutic Accelerator
- …