Використання поляриметрії для вимірювання рельєфу місцевості

The article discusses modern geodetic measurement methods of relief, their advantages and disadvantages. It is also offered a polarimetric measurement method of relief. This method is intended for measuring relief and can also be used to measure slope road and airport paving, railways to geometric description of the surface complex engineering objects, such as bridges, roofs of buildings, architectural elements.Статья посвящена проблеме использования поляриметрии для измерения рельефа местности. Предложен поляриметрический метод измерения. В сравнении с существующими методами измерения поляриметрический метод обеспечивает сокращение времени и при этом обеспечивает высокую точность. Он обеспечивает непрерывность и высокую точность измерения за счёт использования поляриметра, высокую скорость и низкую трудоемкость измерительного процесса за счёт автоматизации процесса измерения.Статтю присвячено проблемі використання поляриметрії для вимірювання рельєфу місцевості. Запропоновано поляриметричний метод вимірювання. У порівнянні з наявними методами вимірювання поляриметричний метод забезпечує скорочення часу вимірювання й при цьому забезпечує високу точність. Він забезпечує неперервність і високу точність вимірювання завдяки застосуванню поляриметра, високу швидкість і низькі трудозатрати вимірювального процесу за рахунок автоматизації процесу вимірювання

Sensitivity of Volume-regulated Anion Current to Cholesterol Structural Analogues

Depletion of membrane cholesterol and substitution of endogenous cholesterol with its structural analogues was used to analyze the mechanism by which cholesterol regulates volume-regulated anion current (VRAC) in endothelial cells. Depletion of membrane cholesterol enhanced the development of VRAC activated in a swelling-independent way by dialyzing the cells either with GTPγS or with low ionic strength solution. Using MβCD–sterol complexes, 50–80% of endogenous cholesterol was substituted with a specific analogue, as verified by gas-liquid chromatography. The effects of cholesterol depletion were reversed by the substitution of endogenous cholesterol with its chiral analogue, epicholesterol, or with a plant sterol, β-sitosterol, two analogues that mimic the effect of cholesterol on the physical properties of the membrane bilayer. Alternatively, when cholesterol was substituted with coprostanol that has only minimal effect on the membrane physical properties it resulted in VRAC enhancement, similar to cholesterol depletion. In summary, our data show that these channels do not discriminate between the two chiral analogues of cholesterol, as well as between the two cholesterols and β-sitosterol, but discriminate between cholesterol and coprostanol. These observations suggest that endothelial VRAC is regulated by the physical properties of the membrane

Modulation of Endothelial Inward-Rectifier K+ Current by Optical Isomers of Cholesterol

Membrane potential of aortic endothelial cells under resting conditions is dominated by inward-rectifier K+ channels belonging to the Kir 2 family. Regulation of endothelial Kir by membrane cholesterol was studied in bovine aortic endothelial cells by altering the sterol composition of the cell membrane. Our results show that enriching the cells with cholesterol decreases the Kir current density, whereas depleting the cells of cholesterol increases the density of the current. The dependence of the Kir current density on the level of cellular cholesterol fits a sigmoid curve with the highest sensitivity of the Kir current at normal physiological levels of cholesterol. To investigate the mechanism of Kir regulation by cholesterol, endogenous cholesterol was substituted by its optical isomer, epicholesterol. Substitution of ~50% of cholesterol by epicholesterol results in an early and significant increase in the Kir current density. Furthermore, substitution of cholesterol by epicholesterol has a stronger facilitative effect on the current than cholesterol depletion. Neither single channel properties nor membrane capacitance were significantly affected by the changes in the membrane sterol composition. These results suggest that 1) cholesterol modulates cellular K+ conductance by changing the number of the active channels and 2) that specific cholesterol-protein interactions are critical for the regulation of endothelial Kir

Effects of millimeter wave irradiation and equivalent thermal heating on the activity of individual neurons in the leech ganglion

Many of today's radiofrequency-emitting devices in telecommunication, telemedicine, transportation safety, and security/military applications use the millimeter-wave (MMW) band (30-300 GHz). To evaluate the biological safety and possible applications of this radiofrequency band for neuroscience and neurology, we have investigated the physiological effects of low-intensity 60 GHz electromagnetic irradiation on individual neurons in the leech midbody ganglia. We applied incident power densities of 1, 2, and 4 mW/cm^2 to the whole ganglion for a period of 1 minute, while recording the action potential with a standard sharp-electrode electrophysiology setup. For comparison, the recognized U.S. safe exposure limit is 1 mW/cm^2 for 6 minutes. During the exposure to MMWs and gradual bath heating at a rate of 0.04 ºC/sec (2.4 ºC/min), the ganglionic neurons exhibited similar dose-dependent hyperpolarization of the plasma membrane and decrease in the action potential amplitude. However, narrowing of the action potential half-width during MMW irradiation at 4 mW/cm^2 was 5 times more pronounced, as compared to equivalent bath heating of 0.6 ºC. Even more dramatic difference in the effects of MMW irradiation and bath heating was on the firing rate, which was suppressed at all applied MMW power densities and was increased in a dose-dependent manner during gradual bath heating. The mechanism of enhanced narrowing of action potentials and suppressed firing by MMW irradiation, as compared to gradual bath heating, is hypothesized to involve specific coupling of MMW energy with the neuronal plasma membrane

Control method in cognitive maps based on weights increments

Когнітивні карти широко використовуються для моделювання складноструктурованих багатовимірних систем різної природи.Метою даної роботи є розробка і дослідження методу управління імпульсним процесом когнітивної карти, що використовує прирости вагових коефіцієнтів ребер в якості керуючих впливів. У статті запропоновано модель керованого імпульсного процесу для цього випадку, а також критерій оптимальності для формування управління. Виведено закон керування та досліджено стійкість замкненої системи. Алгоритм змодельовано на прикладі когнітивної карти соціальнонавчального процесу студента. Результати розробленого методу підтверджують можливість ефективного переводу вершин когнітивної карти на нові рівні.Introduction. Cognitive maps are widely used for modeling large multidimensional systems. These are weighted oriented graphs that represent concepts and relations between them. When external or internal disturbances affect the system impulse process is initiated. It is described by first-order equation in increments of vertices coordinates. A number of articles solved a problem of control in cognitive map’s impulse process by means of control theory methods. But all of them used external control inputs, i.e. resources of the vertices, for this purpose. The purpose of the article is to develop new method of control where cognitive map’s edges weights are used as controls for impulse process stabilisation. Results. New method of control of cognitive maps was developed. It is based on varying of the map’s edges weights. It was supposed that some of the vertices may affect other ones in different way, i.e. stronger or weaker. After presenting impulse process model in full coordinates weights increments were added to the difference equation. They were considered as control inputs which were generated according to the control law developed based on quadratic criterion. Stability of the closed-loop system was demonstrated. To verify the results, method was simulated using cognitive map of student’s socio-educational process. Finally we obtained that for stable cognitive map vertices’ coordinates are quickly stabilised at new levels via edges’ weights varying. Conclusion. Applying the proposed method of control based on weights varying to impulse process of cognitive map allows setting vertices coordinates on desired levelsКогнитивные карты широко используются для моделирования сложноструктурированных многомерных систем разной природы. Особой важностью обладает вопрос управления динамикой импульсного процесса в системе, описываемой когнитивной картой. Целью данной работы является разработка и исследование такого метода управления, который использует приращения весовых коэффициентов ребер когнитивной карты в качестве управляющих воздействий. В статье предложена модель управляемого импульсного процесса для этого случая, а также критерий оптимальности для формирования управления. Выведен закон управления и исследована устойчивость замкнутой системы. Алгоритм промоделирован на примере когнитивной карты социальноучебного процесса студента. Результаты разработанного метода подтверждают возможность эффективного перевода вершин когнитивной карты на новые уровни

Когнитивное моделирование динамики принятия решений для стабилизации неустойчивых режимов в социально-учебном процессе студента

Проблематика. У роботі розглядається соціально-навчальний процес студента вищого навчального закладу. При цьому він допускає представлення у формі когнітивної карти, нестійкий імпульсний перехідний процес якої є предметом дослідження у статті. Мета дослідження. Побудова когнітивної карти студента і стабілізація нестійкого імпульсного процесу в описуваному нею соціально-навчальному процесі студента. Методика реалізації. Спочатку експертним шляхом встановлено взаємозв’язки між основними поняттями предметної області, на основі чого побудовано когнітивну карту. Потім за допомогою методу модального керування з теорії автоматичного керування було розроблено алгоритм стабілізації імпульсного процесу цієї когнітивної карти через безпосереднє варіювання ресурсами системи. Результати дослідження. Моделювання підтвердило, що за допомогою запропонованої методики можна швидко стабілізувати імпульсний соціально-навчальний процес студента. При цьому значення, на яких встановлюються координати вершин когнітивної карти, є задовільними з практичної точки зору. Висновки. Проведені дослідження дали змогу знайти метод прийняття рішень для стабілізації динамічної системи, що описує соціально-навчальний процес студента.Background. The paper considers social-educational process of high school student. It allows for cognitive map representation with unstable impulse transient process which is subject of research in given paper. Objective. To build student’s cognitive map and to stabilize unstable impulse process in social-educational process described by it. Methods. Firstly, interrelations among main concepts of subject domain were set by experts. Cognitive map was built based on this. Then stabilization algorithm for this cognitive map’s impulse process by means of direct system resources varying was developed using modal control method from automatic control theory. Results. Simulation confirmed that it is possible to quickly stabilize student’s impulse social-educational process based on the proposed strategy. Here vertices coordinates are set at practically satisfactory values. Conclusions. Research provided in the paper allowed finding decision-making method to stabilize dynamic system which describes student’s social-educational process.Проблематика. В работе рассматривается социально-учебный процесс студента высшего учебного заведения. При этом он допускает представление в форме когнитивной карты, неустойчивый импульсный переходный процесс которой является предметом исследования в статье. Цель исследования. Построение когнитивной карты студента и стабилизация неустойчивого импульсного процесса в описываемом ею социально-учебном процессе студента. Методика реализации. Сначала экспертным путем установлены взаимосвязи между основными понятиями предметной области, на основе чего построена когнитивная карта. Затем с помощью метода модального управления из теории автоматического управления был разработан алгоритм стабилизации импульсного процесса этой когнитивной карты путем непосредственного варьирования ресурсами системы. Результаты исследования. Моделирование подтвердило, что с помощью предложенной методики можно быстро стабилизировать импульсный социально-учебный процесс студента. При этом значения, на которых устанавливаются координаты вершин когнитивной карты, являются удовлетворительными с практической точки зрения. Выводы. Проведенные в статье исследования позволили найти способ принятия решений для стабилизации динамической системы, описывающей социально-учебный процесс студента

Comparison of the effects of millimeter wave irradiation, general bath heating, and localized heating on neuronal activity in the leech ganglion

The use of electrically-induced neuromodulation has grown in importance in the treatment of multiple neurological disorders such as Parkinson’s disease, dystonia, epilepsy, chronic pain, cluster headaches and others. While electrical current can be applied locally, it requires placing stimulation electrodes in direct contact with the neural tissue. Our goal is to develop a method for localized application of electromagnetic energy to the brain without direct tissue contact. Toward this goal, we are experimenting with the wireless transmission of millimeter wave (MMW) energy in the 10-100 GHz frequency range, where penetration and focusing can be traded off to provide non-contact irradiation of the cerebral cortex. Initial experiments have been conducted on freshly-isolated leech ganglia to evaluate the real-time changes in the activity of individual neurons upon exposure to the MMW radiation. The initial results indicate that low-intensity MMWs can partially suppress the neuronal activity. This is in contrast to general bath heating, which had an excitatory effect on the neuronal activity. Further studies are underway to determine the changes in the state of the membrane channels that might be responsible for the observed neuromodulatory effects. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Radiation and the Risk of Chronic Lymphocytic and Other Leukemias among Chornobyl Cleanup Workers

Background: Risks of most types of leukemia from exposure to acute high doses of ionizing radiation are well known, but risks associated with protracted exposures, as well as associations between radiation and chronic lymphocytic leukemia (CLL), are not clear.
 Objectives: We estimated relative risks of CLL and non-CLL from protracted exposures to low-dose ionizing radiation.
 Methods: A nested case–control study was conducted in a cohort of 110,645 Ukrainian cleanup workers of the 1986 Chornobyl nuclear power plant accident. Cases of incident leukemia diagnosed in 1986–2006 were confirmed by a panel of expert hematologists/hematopathologists. Controls were matched to cases on place of residence and year of birth. We estimated individual bone marrow radiation doses by the Realistic Analytical Dose Reconstruction with Uncertainty Estimation (RADRUE) method. We then used a conditional logistic regression model to estimate excess relative risk of leukemia per gray (ERR/Gy) of radiation dose.
 Results: We found a significant linear dose response for all leukemia [137 cases, ERR/Gy = 1.26 (95% CI: 0.03, 3.58]. There were nonsignificant positive dose responses for both CLL and non-CLL (ERR/Gy = 0.76 and 1.87, respectively). In our primary analysis excluding 20 cases with direct in-person interviews less than 2 years from start of chemotherapy with an anomalous finding of ERR/Gy = –0.47 (95% CI: less than –0.47, 1.02), the ERR/Gy for the remaining 117 cases was 2.38 (95% CI: 0.49, 5.87). For CLL, the ERR/Gy was 2.58 (95% CI: 0.02, 8.43), and for non-CLL, ERR/Gy was 2.21 (95% CI: 0.05, 7.61). Altogether, 16% of leukemia cases (18% of CLL, 15% of non-CLL) were attributed to radiation exposure.
 Conclusions: Exposure to low doses and to low dose-rates of radiation from post-Chornobyl cleanup work was associated with a significant increase in risk of leukemia, which was statistically consistent with estimates for the Japanese atomic bomb survivors. Based on the primary analysis, we conclude that CLL and non-CLL are both radiosensitive.