The following essay examines how literary narration can transmit the historical memories and aesthetic emotions related to the tragic exile experience of the Ubykh people. When Russia subjugated the northwest Caucasus (present-day Sochi, Russia) in the 1860s, the Ubykh were expelled by Russian troops and had to flee to Turkey. The survivors were scattered around Turkey and assimilated into Turkish culture. The Last of the Departed (1974), a historical novel by Bagrat Shinkuba, an Abkhazian writer, narrating about one of the most tragic events in the history of exiles – the death of the Ubykh people and their language – shows that historical fiction may be an instrument contributing to the memorialization of ethnic identity. It also exposes the ideological accents and focusing of the displayed events.

Growth and photosynthetic characteristics, inducibility of the CAM pathway and the functioning of the antioxidant defense system were investigated in Rosularia elymaitica (Crassulaceae) under drought and UV stresses. Drought did not substantially affect the growth of the plants, but it significantly reduced leaf thickness as well as osmotic potential, water potential and relative water content. In contrast, UV radiation treatment affected neither growth nor the water relations of leaves. Water limitation for 12 days caused a significant increase in nighttime PEPC and NAD-MDH activity and an increase in Δtitratable acidity relative to well-watered plants. The nighttime CO2 net assimilation rate increased significantly in drought-stressed plants but was still negative, resembling a C3-like pattern of gas exchange. Twenty days of UV treatment, increased Δtitratable acidity slightly and increased only daytime PEPC activity, and did not affect other parameters of carbon metabolism. As judged by maintenance of membrane integrity and stable amounts of H2O2 under UV stress, the antioxidant defense system effectively protected the plants against UV radiation. In contrast, oxidative stress occurred under severe drought stress (20 days of withholding water). Except for higher daytime APX activity in the UV-treated plants, enzyme activity in the control and in the drought- and UV-stressed plants did not show any diurnal fluctuation during 24 h. Temporal changes in Δtitratable acidity and ΔPEPC activity coincided closely with those of antioxidant enzymes; both started to increase after 12 days of drought stress. These results indicate that drought stress but not UV radiation induced the CAM-cycling pathway in R. elymaitica.

We study the migrants' assimilation, which we conceptualize as forming human capital productive on the labor market of a developed host country, and we link the observed frequent lack of assimilation with the relative deprivation that the migrants start to feel when they move in social space towards the natives. We presume that the native population is heterogeneous and consists of high-skill and low-skill workers. The presence of assimilated migrants might shape the comparison group of the natives, influencing the relative deprivation of the low-skill workers and, in consequence, the choice to form human capital and become highly skilled. To analyse this interrelation between assimilation choices of migrants and skill formation of natives, we construct a coevolutionary model of the open-to-migration economy. Showing that the economy might end up in a non-assimilation equilibrium, we discuss welfare consequences of an assimilation policy funded from tax levied on the native population. We identify conditions under which such costly policy can bring the migrants to assimilation and at the same time increase the welfare of the natives, even though the incomes of the former take a beating.

The analysis of water self-purification process includes headstreams of rivers in the Upper Silesian agglomeration: the Bierawka, the Kłodnica, Bielszowicki creek and the Szotkówka. These are rivers characterized by small natural flows and a significant anthropogenic pol I utant load. Results of our own research on the self-purification rate were used. The attention was focused on biodegradable substances. The biodegradation rate coefficient k, and water assimilative capacity were determined. Within the same rivers, their particular parts differ in types of a riverbed and swift currents alternate with slow flows. In the case of Bielszowicki creek and the Szotkówka River impoundments were observed, which results in different self-purification conditions. In all investigated parts the rate of organic substance removal, characterized byk, coefficients, was usually much higher than the literature values for comparable rivers, which usually are below 2.0, rarely exceeding 3.0. The creek impoundments occurring in the watercourse beds do not always have a positive impact on the water quality. The role of the creek impoundments in the river self-purification process and their impact on water ecosystems require separate investigations.

For majority of running waters point pollution sources are the main sources of pollution. Knowing the water self-purification capacity one can modify the quality of waters through proper management of the discharged pollutants. This study focuses on identifying such solutions for pollutant discharge into the Kłodnica and Bytomka rivers, which would allow for achieving at least the Ill class of surface water quality. Simulation of selected wastewater management scenarios was carried out. The best solutions for the water environment were identified. Only environmental effects which resulted in improvement of the water quality were analyzed. The economical aspect of actions, the undertaking ofwhich is indispensable for achieving the assumed goal, was not taken into account. The selection of the best solutions considering the cost effectiveness cannot be made until a feasibility study for particular undertakings has been completed. Sal i nity and biodegradable pollutants determined by BOD coefficient were taken into consideration. The simulation was carried out using an integrated simulation model IRM (Integrated River Model). In order to protect the river from excessive salinity the optimum solution for the Bytomka River would be desalination, whereas for the Kłodnica River- directing salty mining waters outside its catchment. For protection from biodegradable pollutants the only solution would be tightening the effectiveness criteria for municipal wastewater treatment. Meeting the minimum standards for wastewater treatment, currently obligatory in municipal wastewater treatment plants, will not ensure the assumed water purity level in these rivers.

Influence exerted by various concentrations (0.01 to 50 ppm) of some chlorinated hydrocarbons (Aroclor 1254, Aroclor 1242, pp'DDE, pp'DDT and Lindane (ɣ НСН)) upon the photosynthetic assimilation of 14C02 in Antarctic marine diatom assemblage dominated by Corethron criophilum and some species of Nitzschia (Fragilariopsis group) has been investigated. The photosynthesis was fully inhibited by Lindane (ɣ HCH) in all applied concentrations To smaller extent the photosynthetic process was inhibited in turn by Aroclor 1242, pp'DDE and pp'DDT successively. Aroclor 1254 proved to be the least toxic. The possibility of the decrease of the primary production of the Antarctic diatoms caused by the chlorinated hydrocarbons was discussed.

The aim of this paper is twofold: to estimate the unsteady pressure-flow variations in gas transmission pipelines using the ensemblebased data assimilation approach and to analyse the strength of steel tubes reinforced with composite sleeves containing localized part-wall thickness loss caused by corrosion while taking into consideration a safe operating pressure of the pipeline. For a steel thin-walled cylinder containing a partwall metal loss, a flexible wrap of fibreglass as well as carbon glass with epoxy resin are determined. The strength of the repaired pipeline with two kinds of materials for sleeves is investigated taking into consideration the internal pressure at the defect location. For the case study, a section of the Yamal transit pipeline on the Polish territory is selected. The results enable pipeline operators to evaluate the strength of corroded steel pipelines and develop optimal repair activities, which are of vital importance for the maintenance and operation of underground steel networks.

The Author presents in this paper a concept of research on the Jewish ethos internalized in the groups representing main political trends that were popular among the Polish Jewry in the interwar Poland (1918-1939). These trends are: Zionism, Socialism, Folkizm and a policy of Assimilation. Analysis of above group's ethos covers research on the following issues: values and attitudes constituting the ethos of a specific group, sources and function of the ethos and instruments of communication used in transmission of the ethos.