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The interaction of plants with certain types of parasites leads to the formation of galls, organised structures that create the habitat of the parasite, caused by an abnormal proliferation of host plant's cells under the influence of growth regulators, secreted by the parasite, or by the plant itself under the influence of the parasite. Arthropods, mites in particular, are the largest group of gall-inducing phytoparasites, but the mechanisms of their interaction with plants remain virtually unexplored. The interaction of the gall-inducing eriophyoid mite Fragariocoptes setiger with Fragaria viridis plants was used as a model gall-mite system where data were obtained on the changes in the histological structure of F. viridis leaf blades under the influence of the mites as well as F. viridis gene expression during gall formation. For histological purposes, gall formation was split into four stages with each corresponding to the age of the gall as well as to specific changes that occur during that period. A dramatic change of adaxial-abaxial polarity of the lamina throughout the four stages was observed. Moreover, qRT-PCR analysis of F. viridis gene expression in the developing gall revealed changes in the expression levels of certain meristem-specific genes, as well as the genes that determine adaxial-abaxial polarity and signalling of phytohormones. [ABSTRACT FROM AUTHOR]

The review represents the results of researches of vitamin D receptor characteristics and its genetic polymorphism, which is variable in different populations, and also depends on age and gender. This polymorphism determines the association of vitamin D different concentration with the probability of bronchial asthma or chronic obstructive pulmonary disease development, and therefore the different efficacy of drug correction of vitamin D deficiency. However, the scientific data are contradictory, the molecular mechanisms of connection between vitamin D and bronchial tonus or allergic reactions remain unclear, which emphasizes the importance of studies to clarify the role of vitamin D in inflammatory, immune disorders in bronchial obstructive syndrome. [ABSTRACT FROM AUTHOR]

Предложена методика топологического моделирования химико-технологических систем на основе парного взаимодействия потоков. Такое представление производственных схем дает возможность формализовать их структуру и создать язык описания, позволяющий разрабатывать программное обеспечение для создания математической модели. Определены интегральные характеристики для оценки эффективности тепломассообмена в элементах системы. Выполнена проверка на адекватность метода моделирования. [ABSTRACT FROM AUTHOR]

The increasing demand of energy sources for urban, household and industrial facilities requires strategies development for seeking new energy sources. In recent years an important problem is to have energy storage, energy production and energy consumption which fulfill the environment friendly expectations. A lot of attention is devoted to renewable energy sources. One of the most attracting among them is energy production form geothermal sources. At a few meters below the earth's surface the underground maintains a constant temperature in an approximation through the year allowing to withdraw heat in winter for heating needs and to surrender heat during summer for air-conditioning purposes. Heat pump is a rapidly developing technology for heating and domestic hot water production. Using ground as a heat source, heat exchange is carried out with heat pumps compound to vertical ground heat exchanger tubes that allows the heating and cooling of the buildings utilizing a single unit installation. Heat pump unit provides a high degree of productivity with moderate electric power consumption. In this paper a theoretical performance study of a vapor compression heat pump system with various natural and synthetic refrigerants (HFCs) is presented. Operation mode of the heat pump unit was chosen according to European Standard EN14511-2:2007 and EN255-2. An influence of discharge temperature on system performance was evaluated at different boiling temperatures. The comparison of mass flow rate and coefficient of performance for considered refrigerants at constant cooling capacity and condensation temperature was performed. [ABSTRACT FROM AUTHOR]

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The physiological state of the leaves of the small-leaved linden ( Tilia cordata), silver birch ( Betula pendula), and northern white cedar ( Thuja occidentalis) under urban conditions was assessed via recording the kinetics of chlorophyll under fluorescence induction. Different sensitivities of the plants to adverse growing conditions were revealed. The most sensitive parameters of the fluorescence JIP test, viz., PI, F/ F, and F/ F, were identified as indicators of the physiological state of the urban phytocoenosis. Recommendations for the application of the method for monitoring studies are presented. [ABSTRACT FROM AUTHOR]

The effect of phenolics, present in wastes of pulp and paper industry, on photosynthesis in microalgae Scenedesmus quadricauda has been studied, analyzing the induction curves of prompt and delayed chlorophyll fluorescence and light curves of nonphotochemical quenching of fluorescence. Energization of photosynthetic membranes was impaired at low concentrations (0.1 mM) of phenol and pyrocatechol. At higher concentrations, phenol and pyrocatechol inhibited electron transport in PS II and increased the share of Q-nonreducing centers. As a result, the rate of P reduction declined. These results indicate that the parameters of fluorescence induction curves can be used for detecting phenol and pyrocatechol in the environment at early stages of toxic effects. [ABSTRACT FROM AUTHOR]