42 research outputs found
Strategy of mine ventilation control in optimal mode using fuzzy logic controllers
The issues related to improving the efficiency of automatic ventilation control systems of mines that regulate the air supply to the mine in accordance with the need are considered. During the tests of such a system in the 3RU mine of OAO Belaruskali, the shortcomings of its existing, implementation, associated with the incorrect choice of the most difficult-to-ventilate direction, were revealed. The possibilities of implementing a control strategy, in which the system automatically determines the optimal configuration of the operating modes of fans and regulators, are demonstrated. As an alternative to the implemented algorithms, it is proposed to use a fuzzy control device to account for the nonlinearity of the dependence of the input and output parameters of ventilation equipment and to set the conditions for the optimal operating mode of the system in a declarative form. To assess the effectiveness of the proposed approach, the data of simulation modeling of the current ventilation mode and the transition from one ventilation mode to another are analyzed with comparison with the actual data of the system operation. The simulation results show that the use of an upgraded control scheme for the main ventilation fan based on fuzzy logic in the implementation of automatic ventilation control systems makes it possible to eliminate the possibility of a shortage of fresh air in the regulated directions of its movement, as well as excessive power consumption of the main ventilation fan
On the nature of picobirnaviruses
The picobirnaviruses (Picobirnaviridae, Picobirnavirus, PBVs) are currently thought to be animal viruses, as they are usually found in animal stool samples. However, no animal model or cell culture for their propagation has yet been found. In 2018, a hypothetical assumption about PBVs belonging to prokaryotic viruses was put forward and experimentally substantiated. This hypothesis is based on the presence of Shine–Dalgarno sequences in the genome of all PBVs before three reading frames (ORF) at the ribosomal binding site, with which the prokaryotic genome is saturated, while in the eukaryotic genome such regions occur with low frequency. The genome saturation with the Shine–Dalgarno sequences, as well as the preservation of this saturation in the progeny, according to scientists, allows us to attribute PBVs to prokaryotic viruses. On the other hand, there is a possibility that PBVs belong to viruses of eukaryotic hosts – fungi or invertebrates, since PBVlike sequences similar to the genome of fungal viruses from the families of mitoviruses and partitiviruses have been identified. In this regard, the idea arose that, in terms of reproduction mode, PBVs resemble fungal viruses. The divergence of views on the true PBV host(s) has sparked discussions among scientists and required further research to elucidate their nature. The review highlights the results of the search for a PBV host. The reasons for the occurrence of atypical sequences among the PBV genome sequences that use an alter native mitochondrial code of lower eukaryotes (fungi and invertebrates) for the translation of viral RNAdependent RNA polymerase (RdRp) instead of the standard genetic code are analyzed. The purpose of the review was to collect arguments in support of the hypothesis about the phage nature of PBVs and to find the most realistic explanation of the reasons for identifying nonstandard genomic sequences for PBVs. Based on the hypothesis about the genealogical relationship of PBVs with RNA viruses from other families with similar segmented genomes, such as Reoviridae, Cystoviridae, Totiviridae and Partitiviridae, virologists support the assumption of a decisive role in the origin of atypical PBVlike reassortment strains between PBVs and viruses of the listed families. The collected arguments given in this review indicate a high probability of a phage nature of PBVs. The data presented in the review show that the belonging of PBVlike progeny to prokaryotic or eukaryotic viruses is determined not only by its genome saturation level with a prokaryotic motif, standard or mitochondrial genetic code. The primary structure of the gene encoding the viral capsid protein responsible for the presence or absence of specific proteolytic properties of the virus that determine its ability for independent horizontal transmission into new cells may also be a decisive factor
Picobirnaviruses: prevalence, genetic diversity, detection methods
This article presents a general overview of the prevalence, genetic diversity and detection methods of picobirnaviruses (PBVs), which are small, non-enveloped icosahedral viruses with a segmented double-stranded RNA genome consisting of two segments taxonomically related to the genus Picobirnavirus of the family Picobirnaviridae. This review of scientific papers published in 1988–2019 provides data on the PBV distribution in the nature and a broad host range. PBV infection is characterized as opportunistic, the lack of understanding of the etiological role of PBVs in diarrhea is emphasized, since these viruses are detected both in symptomatic and asymptomatic cases. The concept of PBV infection as a chronic disease caused by a long-lasting persistence of the virus in the host is considered. Such factors as stress syndrome, physiological conditions, immune status and host age at the time of primary PBV infection influence the virus detection rate in humans and animals. The possible zoonotic nature of human PBV infection is noted due to the capacity for interspecies PBV transmission acquired during evolution as a result of the reassortment of the genome segments of different viruses infecting the same host. Data providing evidence that PBVs belong to eukaryotes and a challenging hypothesis stating that PBVs are bacterial viruses are presented. The need to intensify work on PBV detection because of their wide distribution, despite the complexity due to the lack of the cultivation system, is emphasized. Two strategies of RT-PCR as main PBV detection methods are considered. The genomes of individual representatives of the genus isolated from different hosts are characterized. Emphasis is placed on the feasibility of developing primers with broader specificity for expanding the range of identifiable representatives of the genus PBV due to a huge variety of their genotypes. The importance of effective monitoring of PBV prevalence for studying the zoonotic and anthroponotic potential using metagenomics analysis is highlighted, and so is the possibility of using PBV as a marker for environmental monitoring
Impact on the budget of ONLS program of vedolizumab introduction for the treatment of inflammatory bowel disease
Aim. Evaluation of the impact on the budget of the program for the provision of necessary medications (ONLS program) for the inclusion of a new drug vedolizumab for the treatment of adult patients with moderate or severe active ulcerative colitis (UC) and moderate or severe active Crohn’s disease (CD). Material and methods. The analysis provides a retrospective study based on published data. Based on the results of the auctions for the purchase of compared drugs, the size of the target population of the patients was calculated in the framework of ONLS. The calculation was carried out taking into account the proportion of drugs used for the therapy of inflammatory bowel diseases (IBD) in the total volume of purchased inhibitors of TNF-a. For the target group identified, the budget load is determined with the gradual replacement of TNFa inhibitors with vedolizumab. The horizon of the study was 3 years. The calculations used the average tender prices for the package of the preparation for 2016. Results. It is established that the cost of 1 year of therapy with vedolizumab is lower than that for infliximab, adalimumab or golimumab. The inclusion of vedolizumab in ONLS implies the subsequent replacement of TNFa inhibitors by vedolizumab: in the first year in 11% of patients with UC and 15% of patients with CD, in the second year in 17 and 32%, respectively, in the 3rd year 28 and 43% respectively. This allows to reduce the budget impact for 3 years for the treatment of UC by 11,9 million rubles, and for CD therapy by 24,1 million rubles. With the increase in the share of vedolizumab on the market by replacing TNFa inhibitors, budgetary savings are increasing. Vedolizumab therapy is the most effective option in the treatment of IBD from a clinical and clinico-economic point of view in comparison with TNFa inhibitors. Conclusion. The inclusion of the drug vedolizumab in ONLS is pharmacoeconomically feasible. The use of vedolizumab in terms of Budget impact Analysis is preferable to the current treatment regimen including infliximab, adalimumab, golimumab and cerolizumab pegol
The relationship of fracture toughness coefficients and geophysical characteristics of rocks of hydrocarbon deposits
This paper contains the results of laboratory tests to determine the fracture toughness coefficient KIC of rocks for terrigenous and carbonate objects by three methods. The tests were carried out by different methods due to the lack of a standard method for determining the fracture toughness characteristics of rocks in Russia. We used the following methods for determining the KIC coefficient: the extension of core specimens with an annular fracture, the action of a concentrated load on a beam specimen with a fracture and the method of bending semi-circular samples with a fracture according to ISRM recommendations.
The paper presents the relationship of the fracture toughness coefficients with the P-wave velocity and porosity. The obtained dependencies characterize the general trend of changing for the studied parameter and can be used in the design of hydraulic fracturing in the fields for which tests were conducted
ECOLOGICAL AND ENERGY ADVANTAGES OF USING OF GENERATOR GAS FROM MUNICIPAL SOLID WASTE
In this paper main advantages of using generator gas, obtained by gasification of municipal solid waste, compared to traditional incineration are analyzed. This article considers the scope of use of the generator gas. The paper describes the environmental and energy aspects of the gasification of municipal solid waste.В данной работе проанализированы основные преимущества использования генераторного газа, полученного при газификации твёрдых бытовых отходов, по сравнению с традиционным сжиганием. Рассмотрены сферы применения генераторного газа. В работе изложены экологические и энергетические аспекты газификации твёрдых бытовых отходов
Лечение хронических воспалительных заболеваний у детей – ДРАМа хеликобактериоза
It was determined the effectiveness of scheme of treatment of children with chronic inflammatory diseases of upper part of digestive tract, associated with Helicobacter pylori. The scheme included: De-nol, Rabeprazole, Amoxicillin, Macmiror (DRAMa). In the research took part 47 children in the age 9,0 ± 0,2. It was acquired 100% eradication level of Helicobacter pylori.Определена эффективность схемы лечения детей с хроническими воспалительными заболеваниями верхнего отдела пищеварительного тракта, ассоциированными с Helicobacter pylori. Схема включала: де-нол, рабепразол, амоксициллин, макмирор (ДРАМа). В исследовании участвовали 47 детей в возрасте (9,0 ± 0,2) года. Получен 100%-й уровень эрадикации Helicobacter pylori
Новые возможности дренажной хирургии рефрактерной глаукомы
Glaucoma is a socially significant disease, which is consistently ranked first or second among causes of visual impairment and blindness. Difficulties with diagnosis verification, treatment algorithms, monitoring, patient compliance to treatment regimens that occur at a certain stage of therapy, as well as medication prescriptions inefficiency lead to progressive vision loss. Numerous surgical techniques often have limited effectiveness. Drainage use is aimed at reducing excessive scarring in filtration area and creating one or more paths of intraocular fluid resorption. The review presents currently existing approaches to refractory glaucoma drainage surgery. Different implant groups are described in details, including those reducing excessive scarring, intracameral drainages and Schlemm's canal implants. Current perceptions of viscocanalostomy and canaloplasty effectiveness in glaucoma surgery are recounted. The advantages of implants, designed to maintain the Schlemm's canal volume, are specified. NiTi is a promising new material for use in glaucoma drainage surgery. Technical characteristics of biocompatibility, possibilities of modern engineering and technical lasers for processing NiTi allow to use this material on microstructural level.Глаукома относится к социально значимым заболеваниям, стабильно находясь на первом или втором местах среди причин ухудшения зрения и слепоты. Трудности с верификацией диагноза, алгоритмами лечения, наблюдения, приверженностью пациента схемам лечения, возникающая на определенном этапе терапии неэффективность медикаментозных назначений приводят к прогрессирующей потере зрения. Многочисленные методики хирургического воздействия зачастую имеют ограниченную эффективность. Использование эксплантодренажей направлено как на снижение избыточного рубцевания в фильтрационной зоне, так и создание одного или нескольких путей резорбции внутриглазной жидкости. В обзоре представлены существующие на сегодняшний день подходы к дренажной хирургии рефрактерной глаукомы. Отдельно рассмотрены группы имплантатов, снижающих избыточное рубцевание, интракамеральные дренажи и имплантаты шлеммова канала. Описаны существующие представления об эффективности вискоканалостомии и каналопластики при хирургии глаукомы. Приведены преимущества имплантатов, направленных на поддержание объема шлеммова канала. Никелид титана - новый перспективный материал для использования в дренажной хирургии глаукомы. Технические характеристики, биологическая совместимость, возможности современного машиностроения и технических лазеров для обработки никелида титана позволяют использовать этот сплав на микроструктурном уровне
Влияние несостоятельности анастомоза на онкологические результаты лечения больных раком прямой кишки
Background. The effect of anastomotic leakage (AL) on oncological outcomes after total mesorectumectomy is controversial.Objective: to investigate the influence of AL and other factors on oncological outcome.Materials and methods. Data of 67 patients underwent total mesorectumectomy with normal healing were compared with those for 16 patients who experienced AL. Long-term oncological outcomes were analysed.Results. Median follow-up was 43 months. AL rate was 19.4 % (16 cases out of 83). Following factors had negative influence on lower 4-year disease-free survival rate and reached statistical significance in univariant analysis: tumor invasion (hazard ratio (HR) 8.8; 95 % сonfidence interval (CI) 1.4–13.7; р = 0.01), metastases in regional lymph nodes (HR 3.5; 95 % CI 1.2–12.3; р = 0.03), tumor stage (р = 0.048), level of tumor differentiation (HR 0.1; 95 % CI 0–0.6; р <0.0001), tumor stenosis (HR 8.8; 95 % CI 1.4–13.7; р = 0.002), AL (HR 3.9; 95 % CI 1.6–37.1; р = 0.01). In the logistic regression analysis independent risk factors for the development of recurrence were not revealed.Conclusion. AL was not proved to be a risk factor of worse oncological outcome. Hence, additional adjuvant treatment or extended follow-up on the basis of the occurrence of AL after low anterior resection of rectal cancer might not be justified.Цель исследования – оценить влияние НА и других факторов риска на онкологический результат лечения.Материалы и методы. Данные 67 пациентов, перенесших тотальную мезоректумэктомию, с целостным анастомозом сравнивали с данными 16 пациентов с диагностированной НА. Проанализированы долгосрочные онкологические результаты.Результаты. Медиана наблюдения составила 43 мес. Частота НА составила 19,3 % (16 случаев из 83). В однофакторном анализе статистически значимыми факторами, снижающими уровень 4-летней выживаемости, стали степень инвазии опухоли (отношение рисков (OР) 8,8; 95 % доверительный интервал (ДИ) 1,4–13,7; р = 0,01), наличие метастазов в регионарных лимфатических узлах (OР 3,5; 95 % ДИ 1,2–12,3; р = 0,03), стадия болезни (р = 0,048), уровень дифференцировки опухоли (ОР 0,1; 95 % ДИ 0–0,6; р <0,0001), стенозирующий характер опухоли (OР 8,8; 95 % ДИ 1,4–13,7; р = 0,002), НА (OР 3,9; 95 % ДИ 1,6–37,1; р = 0,01). В логистическом регрессионном анализе независимых факторов риска развития рецидива не выявлено.Заключение. НА не является фактором риска плохого онкологического исхода. Таким образом, дополнительное лечение адъювантом или сокращение интервала динамического наблюдения за пациентами, имевшими в анамнезе НА после низких передних резекций прямой кишки, не оправдано