Patterns of mercury accumulation in the organs of bank vole Myodes glareolus (Rodentia, Cricetidae)

Mercury (Hg) and its compounds are among the most hazardous environmental pollutants with a high cumulative potential and they can have toxic effects on human and animal health even in low concentrations. Due to the increasing rate of human economic activity and the increase in the amount of Hg in the total cycling of matter, the study of its distribution, transformation, redistribution and accumulation in the abiotic and biotic components of various ecosystems remains important up to the present time. We assessed the content of metal in organs and tissues of the bank vole Myodes (Clethrionomys) glareolus Schreber, 1780 (Rodentia, Cricetidae), a widespread small rodent, caught in different biotopes of forest-steppe and steppe zones of Voronezh region. Measurements of Hg in samples were carried out with a mercury analyzer RA-915+ with the accessory PYRO (Lumex) using the atomic absorption method of cold steam without preliminary sample preparation (the lower limit of mercury detection in samples was 0.001 mg/kg). The sample size was 344 specimens. Mean Hg concentrations ranged from values below the analytical determination threshold to 0.887 mg/kg dry weight in the kidneys, 0.411 in the liver, 0.031 in the muscle tissue, and 0.040 in the brain. A positive correlation was found between the metal content in all possible pairs of organs (except for the “muscle – brain” pair) and a weak negative correlation was found between the Hg level and the mass of the animals. Hg concentrations in the studied organs did not differ between males and females. The metal content in the liver and kidneys of voles from the forest-steppe zone was significantly higher than in those from the steppe zone. Among all studied biotopes (meadow, pine and mixed forest, shrub thickets), the lowest concentrations were observed in animals living in pine forests, while the highest one – in more humidified bush thickets. During the vegetation season, there was a decrease in the average values of animal body mass in the samples and an increase in the content of Hg in the liver and kidneys. The results of the study are relevant in the assessment of atmospheric mercury pollution of terrestrial ecosystems using small mammals, such as Myodes glareolus, as a model object

Digital receivers for low-frequency radio telescopes UTR-2, URAN, GURT

This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. Since 1998, digital receivers performing on-the-fly dynamic spectrum calculations or waveform data recording without data loss have been used at the UTR-2 radio telescope, the URAN VLBI system, and the GURT new generation radio telescope. Here we detail these receivers developed for operation in the strong interference environment that prevails in the decameter wavelength range. Data collected with these receivers allowed us to discover numerous radio astronomical objects and phenomena at low frequencies, a summary of which is also presented.Comment: 24 pages, 15 figure

Formation of complex radiation defects in irradiated materials

Установлены принципы образования сложных вакансионных дефектов (V-кластеров), их ансамблей и закономерности формирования сверхрешеток V-кластеров. Учет дрейфовой составляющей элементарных дефектов в поле упругих напряжений V-кластера позволил адекватно описать его зарождение и развитие. Детально описаны механизмы движения V-кластеров в материале с учетом их взаимодействия друг с другом. Предложен оригинальный физико-математический формализм, в рамках которого оказалось возможным описать фазовый переход беспорядок–порядок, когда ансамбль хаотически распределенных в облучаемом твердом теле V-кластеров переходит в упорядоченное когерентное состояние – сверхрешетку. Строго определена критическая точка фазового перехода и параметры самой решетки дефектов, которые подтверждаются результатами эксперимента. Процесс упорядочения в данной системе представляется движением по материалу незатухающей волны параметра порядка, в то время как другие конфигурационные варианты состояния ансамбля V-кластеров являются быстрозатухающими флуктуациями. Показан механизм связи симметрии сверхрешетки V-кластеров и симметрии исходного кристалла. The principles of formation of the complex vacancy defects (V-clusters), their ensembles and patterns of formation of superlattices of the V-clusters are determined. The inclusion of the drift component of the elementary defects into the field of elastic stresses of the V-cluster in the analysis allowed describing its genesis and development adequately. The mechanisms of motion of the V-clusters in the material are described in detail, considering their interaction with each other. The authors have developed the original physical and mathematical formalism within which it has become possible to describe the order-disorder phase transition when an ensemble of clusters chaotically distributed in the irradiated solid transforms into an ordered coherent superlattice. The critical point of the phase transition and the parameters of the defect lattice itself are determined. They are confirmed by the experimental results. The ordering process in this system is understood as the motion of the undamped wave of order parameter through the material, while other configuration states of the V-cluster ensemble constitute rapidly damping fluctuations. The article also shows the mechanism of linking the symmetry of the V-cluster superlattice to the symmetry of the initial crystal

Формирование сложных радиационных дефектов в облучаемых материалах

The principles of formation of the complex vacancy defects (V-clusters), their ensembles and patterns of formation of superlattices of the V-clusters are determined. The inclusion of the drift component of the elementary defects into the field of elastic stresses of the V-cluster in the analysis allowed describing its genesis and development adequately. The mechanisms of motion of the V-clusters in the material are described in detail, considering their interaction with each other. The authors have developed the original physical and mathematical formalism within which it has become possible to describe the order-disorder phase transition when an ensemble of clusters chaotically distributed in the irradiated solid transforms into an ordered coherent superlattice. The critical point of the phase transition and the parameters of the defect lattice itself are determined. They are confirmed by the experimental results. The ordering process in this system is understood as the motion of the undamped wave of order parameter through the material, while other configuration states of the V-cluster ensemble constitute rapidly damping fluctuations. The article also shows the mechanism of linking the symmetry of the V-cluster superlattice to the symmetry of the initial crystal.Установлены принципы образования сложных вакансионных дефектов (V-кластеров), их ансамблей и закономерности формирования сверхрешеток V-кластеров. Учет дрейфовой составляющей элементарных дефектов в поле упругих напряжений V-кластера позволил адекватно описать его зарождение и развитие. Детально описаны механизмы движения V-кластеров в материале с учетом их взаимодействия друг с другом. Предложен оригинальный физико-математический формализм, в рамках которого оказалось возможным описать фазовый переход беспорядок–порядок, когда ансамбль хаотически распределенных в облучаемом твердом теле V-кластеров переходит в упорядоченное когерентное состояние – сверхрешетку. Строго определена критическая точка фазового перехода и параметры самой решетки дефектов, которые подтверждаются результатами эксперимента. Процесс упорядочения в данной системе представляется движением по материалу незатухающей волны параметра порядка, в то время как другие конфигурационные варианты состояния ансамбля V-кластеров являются быстрозатухающими флуктуациями. Показан механизм связи симметрии сверхрешетки V-кластеров и симметрии исходного кристалла

An Experimental Investigation of Colonel Blotto Games

"This article examines behavior in the two-player, constant-sum Colonel Blotto game with asymmetric resources in which players maximize the expected number of battlefields won. The experimental results support all major theoretical predictions. In the auction treatment, where winning a battlefield is deterministic, disadvantaged players use a 'guerilla warfare' strategy which stochastically allocates zero resources to a subset of battlefields. Advantaged players employ a 'stochastic complete coverage' strategy, allocating random, but positive, resource levels across the battlefields. In the lottery treatment, where winning a battlefield is probabilistic, both players divide their resources equally across all battlefields." (author's abstract)"Dieser Artikel untersucht das Verhalten von Individuen in einem 'constant-sum Colonel Blotto'-Spiel zwischen zwei Spielern, bei dem die Spieler mit unterschiedlichen Ressourcen ausgestattet sind und die erwartete Anzahl gewonnener Schlachtfelder maximieren. Die experimentellen Ergebnisse bestätigen alle wichtigen theoretischen Vorhersagen. Im Durchgang, in dem wie in einer Auktion der Sieg in einem Schlachtfeld deterministisch ist, wenden die Spieler, die sich im Nachteil befinden, eine 'Guerillataktik' an, und verteilen ihre Ressourcen stochastisch auf eine Teilmenge der Schlachtfelder. Spieler mit einem Vorteil verwenden eine Strategie der 'stochastischen vollständigen Abdeckung', indem sie zufällig eine positive Ressourcenmenge auf allen Schlachtfeldern positionieren. Im Durchgang, in dem sich der Gewinn eines Schlachtfeldes probabilistisch wie in einer Lotterie bestimmt, teilen beide Spieler ihre Ressourcen gleichmäßig auf alle Schlachtfelder auf." (Autorenreferat

Tribology properties changes of nanocrystalline Al–Si–N films after annealing

Методом АСМ исследованы микроструктура поверхности, шероховатость и коэффициент трения нанокристаллических пленок l–Si–N % в исходном состоянии и после воздействия отжига в вакууме при температурах 600, 800 и 900 °С.The surface microstructure, roughness and coefficient of friction of nanocrystalline Al–Si–N films in the initial state and after annealing in vacuum at of 600, 800 and 900 °C were investigated using AFM.Работа выполнена при поддержке ГПНИ «Энергетические системы, процессы и технологии» подпрограммы «Эффективные теплофизические процессы и технологии»

A Survey of Experimental Research on Contests, All-Pay Auctions and Tournaments

Many economic, political and social environments can be described as contests in which agents exert costly efforts while competing over the distribution of a scarce resource. These environments have been studied using Tullock contests, all-pay auctions and rankorder tournaments. This survey provides a review of experimental research on these three canonical contests. First, we review studies investigating the basic structure of contests, including the contest success function, number of players and prizes, spillovers and externalities, heterogeneity, and incomplete information. Second, we discuss dynamic contests and multi-battle contests. Then we review research on sabotage, feedback, bias, collusion, alliances, and contests between groups, as well as real-effort and field experiments. Finally, we discuss applications of contests to the study of legal systems, political competition, war, conflict avoidance, sales, and charities, and suggest directions for future research. (author's abstract