Optical bistability in nonlinear system with two loops of feedback

A model of nonlinear optical system surrounded by two loops of feedback is investigated. The cell with the vapor of rubidium - type atoms is taken in the capacity of nonlinear element. Two modes of near-resonant electromagnetic field interacting with the cell are involved in the feedback. Two-dimensional optical bistability domain in location of input field intensities is obtained and dependence of its form and magnitude from the system parameters (photon detunings, feedback factor etc.) is investigated. "Input - output" relations corresponding to different trajectories in the bistability domain are obtained. Cross-hysteresis is studied.Comment: 7 pages, 14 figures, conference ICONO/LAT 2010, Kazan, Russi

“Ural-20R” combines loading drives evaluation in two-stage development of the face

The technological features of the use of high-performance Ural-20R combines in the conditions of potash mines in Russia are described. It is shown that when the capacity of the worked potash seams is over 4 m, a two-layer ore extraction is used. The formation of cutting process, implemented by the second course of the combine in the treatment chamber, is carried out by an incomplete section of the executive bodies. The standard control system, display and protection of the Ural-20R combine does not allow monitoring and reliable estimation of the magnitude of dynamic components on the drives of the mining machine loads, as well as tracking the feed rate of the combine to the face. The regulation of the operating parameters and the assessment of the degree of loading of the drives of the excavating machine in real time are assigned to the operator. The fundamentals of the experimental research methodology for assessing the loading of drives of Ural-20R combines with the destruction of the potash mass by an incomplete section of the executive bodies are described. The device and the operating procedure of the “Vatur” software-recording complex, which measures, records and records the electrical parameters of the drive motors of a mining machine, is described. The process studies results of forming loads on drive elements of Ural-20R combines when mining a face with an incomplete section of executive bodies are presented. It is proved that the work of combine harvesters on the undercut of the formation with a high feed rate is accompanied by significant dynamic loads on the drives of planetary organs and an overload of the drives of the Berm organs, which leads to an accelerated consumption of the resource and emergency failures of the gearboxes and motors of the extraction machine

Результаты исследования продуктивности откормочных свиней в технологическом модуле

Due to the high intensity and profitability of production, pig breeding is an engaging activity for both large agricultural enterprises and farms. Today, however, all the production growth comes from large pig farms and complexes. The share of small-scale farms decreases annually due to the need for modern scienceintensive technical and technological planning solutions that reduce labor costs and maximize the use of animal genetic potential. To solve this problem, the authors have developed a project and manufactured a prototype of a technological module for fattening pigs. The fattening period of pigs was 100 days from the age of three months. Studies showed that average daily gains ranged from 520 to 906 g and feed conversion ratio from 3.05 to 3.6 depending on the year. The consumption of water, electricity, and labor required for animals to gain 1 kg of live weight varied in the range of 6.54-8.25 liters/kg, 0.028-0.069 kWh/kg, and 0.031-0.064 person-hours/kg, respectively. The content of harmful gases such as CO2, NH3, and H2S generally complied with the maximum permissible concentrations, except for some time intervals during the cold season, so it was proposed to install an additional forced air extraction system during this period. The effectiveness of using the developed technological module on small-scale commercial enterprises, based on the obtained technical and economic indicators, is comparable to the hands of large pig farms.Ввиду высокой интенсивности и рентабельности производства свиноводство является привлекательным видом деятельности как для крупных сельскохозяйственных предприятий, так и для фермерских хозяйств. Однако на сегодняшний день весь рост производства приходится на крупные свинофермы и комплексы. Доля мелкотоварных предприятий ежегодно сокращается ввиду отсутствия современных наукоемких технико-технологических и планировочных решений, обеспечивающих снижение трудозатрат и максимальное использование генетического потенциала животных. Для решения обозначенной проблемы авторами статьи был разработан проект и изготовлен опытный образец технологического модуля для откорма свиней. Срок откорма свиней составлял 100 дней с трехмесячного возраста. Исследования показали, что среднесуточные приросты варьировали от 520 до 906 г, а коэффициент конверсии корма – от 3,05 до 3,6 в зависимости от периода года. Затраты воды, электроэнергии и труда, необходимые для набора животными 1 кг живой массы, изменялись в диапазонах 6,54–8,25 л/кг, 0,028–0,069 кВт·ч/кг и 0,031-0,064 чел.-ч/кг соответственно. Содержание вредных газов таких как СО2, NH3, H2S, в целом соответствовало предельно допустимым концентрациям, за исключением некоторых временных промежутков в холодное время года, поэтому была предложена установка дополнительной принудительной системы отвода воздуха в данный период. Эффективность использования разработанного технологического модуля на мелкотоварных предприятиях, исходя из полученных технико-экономических показателей, сопоставима с показателями крупных свиноводческих предприятий

Spatial movement of the Wels catfish (Silurus glanis) in the Danube

Wels catfish (Silurus glanis, Linnaeus, 1758) is one of the most targeted species for recreational and commercial fishing in the Danube River, even though studies of behavior and movement patterns of Wels catfish in the Danube are rare. Wels catfish was caught downstream of Iron Gate II hydropower dam and tagged with an ultrasonic transmitter (Vemco Ltd, V16TP). Nine autonomous receivers (Vemco Ltd, VR 2W) recorded detections of spatial movement downstream of Iron Gate II dam between Serbia and Romania for almost two years, between the years 2015 and 2017. Our telemetry data found that Wels catfish exhibit relatively short movements within a maximum range (≈ 12 km), but as a territorial species most of the time it was recorded by the two receivers, close to the Iron Gate dam and location where it was caught. The longest displacement from the preferable place under Iron Gate II dam was migration to Romanian ship lock and turbines located in the right arm of the Danube River. Location under the river dam is already recognized as a place of aggregation of the fish and thus preference of predatory catfish is strongly connected with food availability. Our data revealed that dam and ship lock blocked further migration of this fish. The last signal received was during the winter 2017, which was a period with extremely low temperature and ice cover on the Danube River. Considering the fact that the ice displaced whole receiver deployment downstream the dam, we might conclude that the tagged catfish disappeared because of ice movement during the winter season. Results can be used for management ensuring habitat requirements and developing of restoration and conservation strategies

Circadian activity of the Wels catfish (Silurus glanis) in the Danube River

In this study, the movements and behaviour of Wels catfish (Silurus glanis, Linnaeus, 1758) were monitored during the different seasons when the water level in the river changed significantly. Wels catfish was caught on the Danube River, rkm 863, and tagged with an ultrasonic transmitter. Deployed Vemco receivers recorded detections of spatial movement between years 2015 and 2017. Our telemetry data found relatively short movements within a maximum range (~12km), but as a territorial species most of the time it was recorded by the two receivers, close to the Iron Gate dam and location where it was caught. Circadian rhythm showed that in the summer period, nocturnal activity is evident while during winter Wels catfish stayed most of the time at the same depth under the water surface. Wels catfish changed depths during the autumn and spring when more activity was recorded. The last signal received was during the winter 2017, which was period with the low temperatures and ice cover on the Danube River. This research shows the value and importance of installing coded acoustic transmitters in fish and monitoring their movement using a series of autonomous receivers deployed in the Danube River. Research by telemetry can be used to better understand fish behaviour and movements and to help improve large river management measures

LAPAROSCOPIC SURGERY IN TREATMENT OF ENDOMETRIAL CANCER (RESULTS OF 7-YEAR CLINICAL EXPERIENCE AT THE N.N. PETROV NATIONAL MEDICAL RESEARCH ONCOLOGY CENTER)

Introduction. The main method of treatment of endometrial cancer, the most common oncological disease, is surgery. Introduction of high-tech operations into gynecological practice promoted active use of laparoscopy in treatment of malignant tumors of the endometrium.Objective. To evaluate effectiveness of video endoscopic surgery in treatment of endometrial cancer.Materials and methods. In the period from 2010 to 2016, 1127 patients with endometrial cancer underwent surgery using video endoscopic complex with high resolution cameras at the N.N. Petrov National Medical Research Oncology Center, Ministry of Health of Russia.Results.  Using video endoscopic technology, excision of the uterus with appendages was performed in 588 (52.3 %) patients, excision of the uterus with appendages and pelvic lymph node dissection was performed in 523 (46.4 %) patients including 16 (1.4 %) patients with serous and papillary serous forms of endometrial cancer who also underwent omentectomy. No intraoperative complications were observed. In the majority of patients, postoperative period was characterized by early activization, satisfactory intestinal peristalsis on day 1, minimal complications, absence of contraindications for adjuvant beam therapy.Conclusion. Video endoscopic technology is a modern method of surgical treatment allowing to perform the full scope of planned radical surgical intervention in patients with endometrial cancer irrespectively of age and concomitant disorders with minimal traumatization, risk of intraand postoperative complications as well as favorable and fast rehabilitation period

Expression of some molecular and biological markers in esophageal tumors of various stages and grades

Objectives: immunohistochemical study of the expression of molecular and biological markers (p53, bcl-2 and ki-67) in esophageal tumors of various stages and grades, and evaluation of the markers in the disease prognosis. Material and methods: the study included 30 patients of a retrospective group with stage II-III squamous cell carcinoma of the esophagus. Immunohistochemical study of paraffi n sections was performed using primary mouse monoclonal antibodies against p53, bcl-2 and ki67, and Reveal Polyvalent HRP-DAB Detection System. Results: diff erences in the rates and expression of molecular and biological markers (p53, bcl-2 and ki-67), controlling apoptosis and proliferation, depended on the tumor stage and grade. Conclusions: fdvanced cancer of the esophagus demonstrated an increase in rates and expression of p53+ and ki-67, as well as in the proliferative activity of tumor cells. Bcl-2 expression was more frequent and intensive in stage II tumors, compared to stage III. Esophageal tumors of higher grades were characterized with higher rates and expression of p53 and ki-67, and conversely for the bcl-2 expression. Th e revealed diff erences can be used in the disease prognosis

An integrated approach to environmental management

Abstract The issues of improving the system of environmental management on the basis of knowledge management, risk-based approach, environmental monitoring are covered in the article. As a result of the carried out researches the algorithm of improvement of system of ecological management is developed. The model of improvement of ecological monitoring is offered. Practical recommendations for improving environmental safety and placing points of observation of the state of the environment are presented.</jats:p