Photography has a special way of bestowing extraordinary meaning on ordinary subjects – we discuss it with Izabela Łapińska from the Leon Schiller National Film School in Łódź.

Our article considers social remittances and social change in Central and Eastern Europe. We show how migration scholarship can be embedded into the wider study of social processes and relations. ‘Social remitting’ sometimes seems to be little more than a slippery catchphrase; however, this article defends the concept. If it is defined carefully and used cautiously, it should help the researcher to think about what, in addition to money, is sent from one society to another and exactly how, thus shedding light on important and insufficiently studied aspects of migration. A close-up view of the processes by which ideas, practices, norms, values and, according to some definitions, social capital and social skills are transferred by migrants across international borders helps researchers to understand more pre-cisely how migration contributes to social change or, in some cases, prevents it from occurring. Our article reviews some of the most interesting arguments and findings presented recently by other scholars and discusses aspects of social remitting which particularly interested us in our own research. The context of our research is social change in Poland: we attempt to understand how migration has con-tributed to wider patterns of social change since 1989 and exactly how it intertwines with other social trends and globalisation influences. This entails a careful focus on both structural conditions and agency and therefore on social remittances.

This article sheds light on the unintended consequences of temporary migration from Poland by com-bining Merton’s functional analysis with Levitt’s work on social remittances. In addition to economic remittances, Polish migrants have been bringing norms, values, practices and social capital to their communities of origin since the end of the nineteenth century. The article presents a juxtaposition of the non-material effects of earlier migration from Poland, dating from the turn of the twentieth century, with those of the contemporary era of migration from Poland since the 1990s. The analysis shows that some aspects, such as negotiating gender roles, the changing division of household labour, individualistic lifestyles, new skills and sources of social capital, and changing economic rationalities are constantly being transferred by migrants from destination to origin communities. Con-temporary digital tools facilitate these transfers and contribute to changing norms and practices in Polish society. The article demonstrates that migration fulfils specific functions for particular sections of Polish society by replacing some functions of the communist state (e.g., cash assistance and loans from communist factories, factory and post-coop cultures) and by facilitating their adaptation to chang-ing conditions (e.g., changing gender relations, new models of family, job aspirations and social mobility).

The paper presents the results of assessment studies of the time course for technical wear in masonry buildings located in the area of mining-induced ground deformations. By using fuzzy inference system (FIS) and the “if-then” rule, corresponding language labels describing actual damage recorded in structure components were translated into scalar outputs describing the degree of damage to the building. Adopting this approach made it possible to separate damage resulting from additional effects coming from mining-induced ground deformations and the natural wear and tear of masonry structure. By using statistical analysis an exponential function for the condition of building damage and the function of natural wear and tear were developed. Both phenomena were subject to studies as a function of time regarding the technical age of building structure. The results obtained were used to develop a model for the course of technical wear of traditionally constructed buildings used within mining areas.

In the course of natural wear and tear buildings located in mining areas are additionally exposed to forced ground deformations. The increase of internal forces in structure components induced by those effects results in creating an additional stress factor and damage. The hairline cracks and cracks of building structure components take place when the intensity value of mining effects becomes higher than the component stress resistance and repeated effects result in the decrease of structure rigidity. The observations of building behaviour in mining areas show that the intensity of mining activity and the multiplicity of its effect play a substantial role in the course of technical wear of buildings. The studies show that the level of damage resulting from mining effects adds up to natural wear and tear of the building and impairs the global technical condition as compared to similar buildings used outside mining areas.

The study makes an attempt to model a complete vibrating guitar including its non-linear features, specifically the tension-compression of truss rod and tension of strings. The purpose of such a model is to examine the influence of design parameters on tone. Most experimental studies are flawed by uncertainties introduced by materials and assembly of an instrument. Since numerical modelling of instruments allows for deterministic control over design parameters, a detailed numerical model of folk guitar was analysed and an experimental study was performed in order to simulate the excitation and measurement of guitar vibration. The virtual guitar was set up like a real guitar in a series of geometrically non-linear analyses. Balancing of strings and truss rod tension resulted in a realistic initial state of deformation, which affected the subsequent spectral analyses carried out after dynamic simulations. Design parameters of the guitar were freely manipulated without introducing unwanted uncertainties typical for experimental studies. The study highlights the importance of acoustic medium in numerical models.

Due to the lower energy consumption and waste production compared to traditional methods, the environmental bioremediation methods based on natural processes have been gradually becoming more prevalent in environmental engineering. Biological methods are used in waste management, wastewater treatment, gas treatment or soil remediation. For the low solubility of some pollutants and lower bioavailability, the use of biological methods may be hampered. This problem might be mitigated with the use of surfactants. This paper presents the results of studies regarding the eff ect of dosing a selected surfactant from the Tween group (Tween 20) on the efficiency of toluene elimination from the air by biofi ltration. The obtained maximum biofi ltration rate was 21.2 g/m3/h and 19.8 g/m3/h for the control bed and for the bed to which the Tween 20 solution was dosed, respectively. The eff ect of Tween was neutral (the effectiveness of toluene removal was insignificantly comparable to the effectiveness of the control series), it did not affect the effectiveness or limited the development of the biofilter microflora.

Tensile structures in general, achieve their load-carrying capability only after the process of initial form-finding. From the mechanical point of view, this process can be considered as a problem in statics. As cable systems are close siblings of trusses (cables, however, can carry tensile forces only), in our study we refer to equilibrium equation similar to those known from the theory of the latter. In particular, the paper regards designing pre-tensioned cable systems, with a goal to make them kinematically stable and such that the weight of so designed system is lowest possible. Unlike in typical topology optimization problems, our goal is not to optimize the structural layout against a particular applied load. However, our method uses much the same pattern. First, we formulate the variational problem of form-finding and next we describe the corresponding iterative numerical procedure for determining the optimum location of nodes of the cable system mesh. We base our study on the concept of force density which is a ratio of an axial force in cable segment to its length.