UTILIZATION OF STATIONARY UNDERWATER SURVEILLANCE SYSTEMS FOR THE ESTIMATION OF UNDERWATER CURRENTS AND SEA DISTURBANCE PARAMETERS

Системы стационарного подводного видеонаблюдения, разработанные в ТОИ ДВО РАН, помимо решения задач наблюдения за состоянием морской биоты прибрежных акваторий залива Петра Великого (Японское море) могут применяться для оценивания характеристик морского волнения и подводных течений. Эти характеристики важны как в контексте сопровождения наблюдений за жизнедеятельностью морских организмов информацией о гидрологических условиях их существования, так и сами по себе – как важные параметры состояния природной среды. В статье рассмотрены несколько методик измерения сигналов вариаций подводных течений и оценивания на их основе частотных свойств поверхностного волнения. Основная идея состоит в отслеживании на основе анализа видео горизонтальных движений легких маркеров под воздействием на них течений. В первой части работы приведены примеры использования искусственных маркеров двух видов – закрепленных на тонкой нити теннисных шариков с небольшой положительной либо отрицательной плавучестью и установленных на дне вертушек. Показано, что при небольших глубинах установки камер частотные свойства сигналов горизонтальных движений маркеров хорошо воспроизводятся в сигналах поверхностного волнения в диапазонах ветровых волн, корабельных волн, волнения зыби, сейшевых колебаний уровня моря с периодами от десятков секунд до десятков минут. Во второй части работы рассмотрены технологии измерений, основанные на использовании естественных маркеров–полей органических и неорганических взвесей, перемещаемых водными потоками перед камерой, либо растительности, изменяющей свой наклон под действием течений. Они могут применяться при отсутствии либо выходе из строя искусственных маркеров. Stationary systems for underwater video surveillance designed in POI FEB RAS apart from solving tasks of marine biot monitoring in the off-shore strip of Peter the Great Bay can be used for estimating characteristics of sea disturbance and underwater currents. These characteristics are essential both for supplementing the observations of life activities of marine organisms with hydrological existence conditions and by itself, as vital parameters of environmental conditions. This work considers several methods of measuring signals of variations of underwater currents and estimating frequency properties of sea disturbance on its basis. The main idea is to track horizontal movements of light markers driven by underwater currents based on the video analysis. The first part of the article presents examples of the utilization of markers of two types: tennis balls with slightly positive or negative buoyancy mounted on thin thread and propellers mounted on the bottom. It is shown that at a small depth of the camera installation, the frequency properties of the signals of markers horizontal movements are easily reproduced in signals of sea surface disturbance in the range of wind waves, sea swells, seiche oscillations of the sea level with a period from tens of seconds to tens of minutes. The second part of the article considers technologies of measurements based on the utilization of natural markers, such as fields of organic and inorganic suspended matter moved by water streams in front of a camera or submerged vegetation, which inclination angle is changed under the influence of currents. These approaches can be used in the absence of artificial markers or their failure.

DHA Modulates Immune Response and Mitochondrial Function of Atlantic Salmon Adipocytes after LPS Treatment

Adipocytes play a central role in overall energy homeostasis and are important contributors to the immune system. Fatty acids (FAs) act as signaling molecules capable to modulate adipocyte metabolism and functions. To identify the effects of two commonly used FAs in Atlantic salmon diets, primary adipocytes were cultured in the presence of oleic (OA) or docosahexaenoic (DHA) acid. DHA decreased adipocyte lipid droplet number and area compared to OA. The increase in lipid load in OA treated adipocytes was paralleled by an increase in iNOS activity and mitochondrial SOD2-GFP activity, which was probably directed to counteract increase in oxidative stress. Under lipopolysaccharide (LPS)-induced inflammation, DHA had a greater anti-inflammatory effect than OA, as evidenced by the higher SOD2 activity and the transcriptional regulation of antioxidant enzymes and pro- and anti-inflammatory markers. In addition, DHA maintained a healthy mitochondrial structure under induced inflammation while OA led to elongated mitochondria with a thin thread like structures in adipocytes exposed to LPS. Overall, DHA possess anti-inflammatory properties and protects Atlantic salmon against oxidative stress and limits lipid deposition. Furthermore, DHA plays a key role in protecting mitochondria shape and function.

ALGORITHM FOR A FORMATION OF A SMALL TRAINING SET USING A MULTILAYER PERCEPTRON FOR A PRIORI ESTIMATES

The paper proposes an algorithm for the formation of a small training set, which ensures a reasonable quality of a surrogate machine learning model trained using this set. The algorithm uses multilayer perceptron to estimate heuristics and select the best next sample for the inclusion in a set. The paper tests the algorithm proposed applying it to the problem of deformation and breaking of a thin thread under the action of a transverse load pulse on it. The possibility to generalize the approach and apply it to building surrogate machine learning models for other physical problems is discussed.

The Miracle of Music: A Conversation with Ennio Morricone

In a conversation with Emanuele Colombo, Ennio Morricone—one of the great contemporary composers—discusses the maestro’s relation to the Society of Jesus. One of the highlights of this interview is a thin thread that unites the masterful soundtrack Morricone composed for the 1986 movie The Mission (on the Jesuit reducciones in Paraguay) with a Mass he dedicated to the first Jesuit pope, Francis, on the occasion of the 200th anniversary of the Society of Jesus’s restoration (2014)

Experimental Studies of the Effect of Vortex Disturbances on the Flow Around the Wing Model at Low Reynolds Numbers

Results of experimental investigations in subsonic wind tunnels, which studied the impact of artificial forcing on the flow in the boundary layer of straight wing model were described. The feature of this work is the use of such locally impact that can change the general flow pattern. The influences of the angle of attack, free stream turbulence level, and wake behind thin thread on the flow near the wing profile were studied at this paper. The method of oil-film based on titanium dioxide was applied for flow visualization, also hot-wire measurements were used. The obtained results were analyzed with the aim of finding the most efficient ways of vortex control to the flow