84 research outputs found

    Study of a novel type of the optical modes in VCSELs

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    We study novel side-emitting modes in VCSEL microcavities. These modes correspond to π-shaped propagation along the mesa diameter, reflection from angled mesa walls and bottom Bragg reflector. We believe this study of π-modes is important for optimization of VCSEL design for improvement of efficiency

    Assessment of Resistance in <i>Burkholderia pseudomallei</i> to Benzalkonium Chloride and Antibiotics

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    The aim of the study was to investigate the features of resistance formation in Burkholderia pseudomallei to quaternary ammonium compounds, as well as to analyze its influence on the development of antibiotic resistance.Materials and methods. 10 strains of melioidosis causative agent with typical cultural and morphological properties have been studied. The selection of variants resistant to benzalkonium chloride was carried out by successive passages on a dense nutrient medium with the addition of a disinfectant in increasing concentrations. The determination of sensitivity to benzalkonium chloride was performed through serial dilutions in agar, to antibacterial drugs from the groups of sulfonamides, β-lactams and tetracyclines – using disk diffusion method. Statistical processing of the obtained results was conducted with the help of the Microsoft Excel 2019 software. Arithmetic mean values and errors of mean values were calculated. The significance of differences between the parameters was determined applying Student’s t-test.Results and discussion. All parental strains showed a similar degree of resistance to the disinfectant compound and most of the strains – susceptibility to the antibiotics tested. Cultivation of B. pseudomallei strains on a nutrient medium with the addition of benzalkonium chloride led to an increase in resistance to this disinfectant. In addition, an increase in the level of resistance to all studied antibiotics was found. Statistical processing of the data collected revealed a significant correlation between the change in sensitivity to benzalkonium chloride and the emergence of resistance to amoxicillin/ clavulanic acid and ceftazidime. It was found that the causative agent of melioidosis, with a natural high susceptibility to benzalkonium chloride, has a high potential for developing resistance to this disinfectant compound, which is of practical importance in the development of disinfection regimens using quarternary ammonium compounds. For the first time, a direct correlation between a decrease in the sensitivity to benzalkonium chloride in B. pseudomallei and emergence of resistance to amoxicillin/clavulonic acid and ceftazidime has been demonstrated

    About the Volunteer Movement at the Medical College URGUPS

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    В статье дан анализ понятия «волонтёрство», как добровольческое движение, его историческое понимание и современная трактовка. Определены задачи, формы и виды деятельности добровольческого движения. Сделан акцент в понимании волонтерства как фактора духовно – нравственного воспитания студенческой молодежи и важного направления деятельности медицинского колледжа города Екатеринбурга.The article focuses on understanding the term "volunteering". The tasks of the volunteer movement as an element of spiritual and moral development in college are defined

    Механизмы обеспечения достоверности и надежности передачи данных по радиоканалу с использованием эстафетной технологии и их реализация на трансиверах с модуляцией LoRa

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    The article is devoted to a detailed description of the algorithms of the operation of the relay-race data transmission system over a radio channel, which ensure high reliability of transporting the results of monitoring the operation of extended objects to the central control panel. The feature of the system is operation at a low power level of transmitters, energy efficiency, which ensures a long-term operation without maintenance, the ability to replace failed elements quickly without stopping the entire system, mobility —  quick installation and start-up of the system. Energy efficiency and operation of the radio channel with a low transmitter power level is ensured by the use of SX 1276 (LoRa) transceivers. The accuracy and reliability of data transmission is ensured by original algorithms, which are described in the paper. In the relay data transmission system, it is possible to use up to 255 relay nodes with their installation at a distance of up to 4 km from each other. Two options of building a system with relay-race transmission have been developed: a system with a simple handover, a system with transmission «Through one». The second option provides more reliable data transfer and higher probability of uptime. With the number of relay nodes equal to 50, the probability of failure-free operation of a simple system is 0.268, and for the system with «Through one» transmission is 0.985. Luchinin A. S., Malygin I. V., Starikov S. I., Chechetkin V. A., Shegal A. A., Belkov S. A. Mechanisms of ensuring the accuracy and reliability of data transmission over a radio channel using relay technology and their implementation on transceivers with LoRa modulation. Ural Radio Engineering Journal. 2023;7(2):191–217. (In Russ.) DOI: 10.15826/urej.2023.7.2.006.Статья посвящена детальному описанию алгоритмов работы системы эстафетной передачи данных по радиоканалу, обеспечивающих высокую надежность транспортировки результатов наблюдения за работой протяженных объектов на центральный пульт контроля. Особенностью системы является работа на малом уровне мощности передатчиков, экономичность по потреблению электроэнергии, обеспечивающая длительную работу без обслуживания, возможность быстрой замены вышедших из строя элементов без остановки всей системы, мобильность —  быстрая установка и запуск системы. Экономичность энергопотребления и работа радиоканала с низким уровнем мощности передатчиков обеспечиваются применением трансиверов SX 1276 (LoRa). Достоверность и надежность передачи данных обеспечивается оригинальными алгоритмами, описание которых приводится в статье. В системе эстафетной передачи данных возможно использование до 255 узлов ретрансляции с установкой их на расстоянии до 4 км друг от друга. Разработаны два варианта построения системы с эстафетной передачей: система с простой эстафетной передачей и система с передачей «через одного». Второй вариант обеспечивает более надежную передачу данных и более высокую вероятность безотказной работы. При числе узлов ретрансляции, равном 50, вероятность безотказной работы простой системы составляет 0,268, а системы с передачей «через одного» —  0,985. Лучинин А. С., Малыгин И. В., Стариков С. И., Чечеткин В. А., Шегал А. А., Бельков С. А. Механизмы обеспечения достоверности и надежности передачи данных по радиоканалу с использованием эстафетной технологии и их реализация на трансиверах с модуляцией LoRa. Ural Radio Engineering Journal. 2023;7(2):191–217. DOI: 10.15826/urej.2023.7.2.006

    Значение экспрессии рАКТ1 при диффузной В-крупноклеточной лимфоме

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    Aim. To evaluate the prognostic value of pAKT1 expression by tumor cells in patients with diffuse large B-cell lymphoma.Materials and methods. The study included 90 patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL), who were treated at the clinic of Kirov Research Institute of Hematology and Blood Transfusion from 2014 to 2017 and received standard first-line polychemotherapy according to the R-CHOP regimen. Using immunohistochemical and morphometric methods, the relative number of tumor cells expressing pAKT1 was determined. Using the two-sided Fisher’s exact test, the relationship of different levels of marker expression with clinical and laboratory parameters of patients and long-term treatment results was analyzed. The impact of pAKT1 on the risk of an adverse event was assessed using the Cox regression analysis.Results. Overexpression of pAKT1 is associated with unfavorable clinical characteristics of patients with DLBCL, excessive expression of the BCL2 and c-Myc oncoproteins, as well as with low rates of overall and progressive survival. Overexpression of pAKT1 is an independent prognostic factor and statistically significantly affects the risk of an adverse outcome in DLBCL.Conclusion. The degree of pAKT1 expression is an informative criterion that allows to predict the course of diffuse large B-cell lymphoma. It is advisable to use the indicated marker when stratifying patients into risk groups.Цель – оценить прогностическое значение экспрессии рАКТ1 опухолевыми клетками у больных диффузной В-крупноклеточной лимфомой.Материалы и методы. В исследование включены 90 пациентов с впервые диагностированной диффузной В-крупноклеточной лимфомой (ДВККЛ), наблюдавшиеся в клинике института с 2014 по 2017 г. и получавшие стандартную полихимиотерапию первой линии по схеме R-CHOP. С помощью иммуногистохимического и морфометрического методов определено относительное количество экспрессирующих рАКТ1 опухолевых клеток. С помощью точного двухстороннего критерия Фишера проанализирована взаимосвязь различных уровней экспрессии маркера с клинико-лабораторными показателями пациентов и отдаленными результатами лечения. Оценку влияния рАКТ1 на риск наступления неблагоприятного события проводили с помощью регрессионного анализа Кокса.Результаты. Гиперэкспрессия рАКТ1 ассоциирована с неблагоприятными клиническими характеристиками больных диффузной В-крупноклеточной лимфомой, избыточной экспрессией онкобелков BCL2, cMyc, а также низкими показателями общей и беспрогрессивной выживаемости. Гиперэкспрессия рАКТ1 является независимым фактором прогноза и статистически значимо влияет на риск возникновения неблагоприятного исхода при ДВККЛ.Заключение. Степень экспрессии рАКТ1 является информативным критерием, позволяющим прогнозировать течение диффузной В-крупноклеточной лимфомы. Указанный маркер целесообразно использовать при стратификации пациентов на группы риска

    Competence of mosquitoes <i>Culex pipiens f.</i> molestus as carriers of West Nile virus under various temperature conditions

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    Introduction. The Culex pipiens mosquito is one of the proven vectors of the West Nile virus (WNV). Culex pipiens f. molestus (Cx. p. f. molestus) is a synanthropic, autogenous, widespread form of the species that can feed on a broad range of hosts, including humans. The temperature of the habitat of insects affects the potential for virus transmission, which determines the likelihood of them carrying the pathogen of West Nile fever. The goal is an experimental study of the temperature of the habitat of larvae on the competence of mosquitoes Cx. p. f. molestus as carriers of WNV. Materials and methods. We used a strain of the WNV (WNV_Volg601/18 genotype 2) and a laboratory culture of mosquitoes Cx. p. f. molestus. The concentration of the virus was detected by plaque formation using Vero cells. Insects were infected orally at the larval stage, with subsequent incubation at 20, 22 or 28C. 72 hours after the emergence of all adults from the pupae, the mosquitoes were immobilized by cold, the sex of imago was determined, the salivary glands were isolated from the females, and the presence of WNV in glandes and its titer were detected. Results. The titer of WNV sufficient to transmit the pathogen through the insect biting was observed in the salivary glands of insects kept at a temperature of 22 and 28C, with the virus titer rising with the temperature increasing. No virus was detected in the salivary glands of female insects kept at a temperature of 20C. Conclusion. Thus, it appears that the habitat temperature is an important factor limiting the replication and content of WNV in the salivary glands of Cx. p. f. molestus

    Secure radio communication systems using encoded signal in time, frequency and phase

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    The original algorithm of transfer 8-bit digital data with use of signal, discretely-encoded in the timing, frequency and phase using the matrix of Costas and of Walsh functions, providing high reserve of work and security from broadband and narrow-band interferences is developed. The algorithms of generation and processing of signals on the receiving side is realized in FPGA of type XC7k325T (Xilinx).A radio communication system on the SDR technology (software defined radio) on the basis of the AD 9361 transceiver (Analog Devices).Разработан оригинальный алгоритм передачи 8-бит цифровых данных с использованием сигнала, дискретно-кодированного по времени, частоте и фазе с помощью матрицы Костаса и функций Уолша. Обеспечивается высокая скрытность работы и защищенность от широкополосных и узкополосных помех. Алгоритмы формирования сигналов и обработки их на приемной стороне реализованы в ПЛИС типа XC7k325T (Xilinx). Система радиосвязи реализована по технологии SDR (программно определяемое радио) на основе трансивера AD 9361 (Analog Devices)

    A screening for serum markers of arbovirus infections in healthy blood donors from the Volgograd Region

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    Volgograd region is considered to be endemic West Nile fever (WNF) area due to the established circulation of the West Nile virus (WNV) therein. Some previous independent studies examining samples collected on the territory of the Volgograd region revealed markers related to the California serogroup (CSG), Sindbis and Ukuniemi viruses. WNF, CSG, Sindbis and Ukuniemi fever mainly being asymptomatic posing thereby a threat of virus spread due to transfusiological manipulations along with vector-borne transmission are manifested by diverse clinical signs. The study was aimed at detection of antibodies specific to West Nile, tick-borne encephalitis, California serogroup (Tyaginya, Inko), Sidbis, and Ukuniemi viruses in blood donors from the Volgograd region. For this, 404 blood sera samples collected from blood donors residing in the Volgograd as well as the Volgograd region were examined by ELISA. It was found that percentage of blood serum samples positive for arbovirus-specific antibodies was 18.32%. Among the, 67 out of 404 (16.58%) samples contained anti-WNV antibodies, 3 out of 279 (1.08%) samples — to tick-borne encephalitis virus, 1 out of 92 (1.09%) — to California serogroup fever and Ukuniemi viruses, and 2 out of 92 (2.17%) — to Sindbis fever virus. Importantly, the peak number of IgG and IgM WNV-positive samples was found among residents of Volgograd (29 out of 110, 26%) and Oktyabrsky district (7 out of 25, 28%). In addition, anti-Sindbis, Ukuniemi and CSG virus antibodies were detected in blood serum samples from blood donors residing in the Kalachevsky region and the city of Volgograd. Analyzing age-related distribution and percentage of seropositive subjects in each age group showed as follows: the lowest percentage (14.5%) was positive for anti-WNV, Sindbis, Ukuniemi and CSG virus antibodies in blood donors aged 32–41 years, whereas the peak percentage (25%) — in the subjects aged 52–61 years. Thus, virus specific antibodies detected in healthy individuals in the aforementioned region evidence about potential recovery after asymptomatic infections. In this regard, further research is required to determine a role of the such arboviruses in the structure of regional infectious diseases. The data obtained suggest a need to continue serological arbovirus monitoring in the Volgograd region

    HARDWARE AND SOFTWARE SYSTEM FOR PSYCHOFUNCTIONAL STATE CORRECTION

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    Рассмотрены некоторые результаты разработки аппаратно-программной системы (АПС) электромагнитного излучения для коррекции стресса. Показано, что АПС с амплитудной модуляцией по псевдо-случайному закону при крайне низких уровнях мощности излучения позволяет корректировать психофункциональное состояние человека.Some results of the development of a hardware-software system (HSS) of electromagnetic radiation for stress correction are considered. It is shown that HSS with amplitude modulation according to a pseudo-random law at extremely low levels of radiation power makes it possible to correct the psycho-functional state of a person
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