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The dynamics of the species richness, breeding density, and structure of the community of birds occupying nest-boxes upon a 50-fold reduction of atmospheric emissions from the Middle Ural Copper Smelter was analyzed based on long-term continuous observations (1989–2020). The total density in the deciduous forest was lower in the heavily polluted zone (impact zone) than in the background zone, while there were no differences in the coniferous forest between the zones. The total breeding density of the community of hole-nesters increased in the impact zone over the 30 years (especially, in the deciduous forest in 2010–2020) after the significant reduction of industrial emissions. The breeding density of the two most abundant species varied in different directions: it increased for pied flycatcher and decreased for common redstart. This led to a change of dominants in the impact zone: redstart dominating until 2012 was replaced by pied flycatcher. The differences in the dynamics of species density are probably determined by the beginning of vegetation recovery near the smelter, which is favorable for pied flycatcher but not for redstart.

The study of the state of green spaces in urbanized areas is important due to their sanitary, hygienic and aesthetic role in the harsh climatic conditions of the Arctic. The objects of research were the green spaces of the urban-type settlement Nikel (the Murmansk region). The assessment of the distribution of tree and shrub species by categories of life state was carried out; revealed damage to leaves by atmospheric emissions, insects and fungi. A high degree of damage from pollution was noted in birch, mountain ash and bird cherry; aspen up to 85 % damaged by aphids; mechanical damage to the trunks was noted in about 26 % of the surveyed trees; 5 % of trees have frost cracks in the trunk. In the course of a comparative assessment of the chemical composition of birch leaves growing in the urbanized territory of Nikel and in forest ecosystems along the gradient of atmospheric pollution in the impact zone of the Pechenganikel plant, it was found that the concentrations of pollutants in birch leaves in technologically disturbed areas exceed background values. Birch leaves in the southern direction from the plant accumulate higher concentrations of Ni, Cu, Pb, Co, Fe than in the western and northern directions. In 2019, the concentrations of heavy metals in birch leaves increased compared to the previous study period (2004). In the urban area, the content of pollutants exceeds not only the values of the regional background, but also the levels identified in forest ecosystems along the gradient of atmospheric pollution. Concentration coefficients Cc show abnormally high values for Ni, Cu, Pb, Co, Fe; the maximum Cc values are noted for Ni and Co.

Evaporation kinetics of tramp elements (M = As and Sn) in liquid iron were investigated by high-temperature gas–liquid reaction experiments and a phenomenological kinetic model. Residual content of As or Sn in the liquid iron ([pct M]) during the evaporation was measured in the temperature range of 1680 °C to 1760 °C. [pct As] and [pct Sn] decreased faster as the reaction temperature and [pct C]0 increased. Assuming first-order reaction kinetics, the apparent rate constants (kM) were obtained at each reaction temperature and [pct C]0. [pct M] in a liquid iron during the top-blown oxygen steelmaking process was simulated, with an emphasis on enlarging the reaction surface area by forming a large number of liquid iron droplets. The surface area and the droplet generation rate were obtained based on the oxygen-blowing condition. The whole surface area increased up to ∼163 times the initial liquid iron (bath) surface area, due to the generation of the droplets. Using the kM obtained in the present study, the evaporation of M during the top-blown oxygen steelmaking process for 200 tonnes of liquid iron was simulated. For a condition of [pct M]0 = 0.005 (M = As and Sn), As and Sn could be removed from the liquid iron, which was seen to be much improved by the consideration of the droplet generation. However, additional actions are required to improve the evaporation rate, as the evaporation rate in the BOF process was not fast enough to be practically considered.

The composition, structure, and spatial distribution of zoobenthos in streams of the Bukhtarma River basin are described and quantitative indicators of benthos in the lower course of the Bukhtarma River are given. The predominance of insects from the orders of mayflies, caddisflies, and freckles is characteristic of the water-courses in the Bukhtarma River basin and is associated with the presence of stony soils in the rivers, rapid flow, moderate-cold-water temperature regime, and high oxygen content in the water – factors that are most favorable for these groups of invertebrates. To assess the ecological state of surface waters in the streams under study by bioindication methods, TBI, BMWP, ASPT, and ERT biotic indices are used. The taxonomic composition of each of the studied watercourses and river sections is formed in accordance with specific environmental conditions associated with natural and anthropogenic factors. It is established that watercourses in the reference areas can be used as reference ones in accordance with the requirements of the EU Framework Water Directive, and the characteristics of invariant States of biocenoses of the lower course of the Bukhtarma River in the impact zone are also given using the criteria of the V. A. Abakumov system of ecological modulations.

Trade turnover of food products between Poland and its neighbouring countries on the external eastern border of the European Union (Ukraine, Belarus and Russia) is an important element of the international trade exchange of Poland. The registered trade turnover had an impact on the Polish economy, whereas, from the point of view of development of areas located within the border impact zone, the unregistered trade that is part of cross-border shopping was of great importance. The aim of the paper is to examine the dynamics and trends of changes in terms of the share of cross-border shopping in the total trade turnover of food products with the above-mentioned countries over the period 2013-2018. A case study analysis conducted in all three countries showed that there was a steady increase in the share of unregistered trade in the total trade volume throughout the entire research period. (original abstract)

The review of literature sources has allowed determining the mechanism of seismic blasts waves in jointed rock mass. The author presents the theoretical formulas for calculating stresses, relative strains and displacement velocities induced in rock mass by large-scale blasts. The formulas take into account the detonation characteristics of explosives, the borehole diameter, the length of explosive charges, the number of simultaneously blasted charges per groups and the factor of explosion energy redistribution to rock throw. Moreover, the formulas include the properties of rocks between the blasting point and a guarded object, and on the exposed surface of a guarded object. The compressive stresses, relative strains and displacement velocities in rocks are calculated from the formulas. The theoretically found change in the displacement velocity versus distance agrees with the field measurement data obtained in an open pit mine of Polyus company. The formulas of stresses and relative strains were used to define seismic impact exerted by large-scale blasts on the barrier of dry dock No. 1. Based on the calculated results, the recommendations are developed on reduction of seismic impact of blasts during dredging in the dock. The research findings are applicable to developing blasting regulations toward reduction in seismic impact of large-scale explosions on exposed surfaces in rock mass, as well as on the ground surface structures and buildings.

Longitudinal inhomogeneity of tracks inscribed in a YAG crystal and the statistics of nonlinear transmittance of the writing beam is studied under conditions of direct femtosecond laser writing in non-thermal mode. Nonlinear transmittance fluctuations inherent in the laser writing were discovered, and their correlation with track inhomogeneity is established. A model of femtosecond laser writing in crystals is built that includes three modes of plastic deformation in the laser impact zone. The modification threshold of the femtosecond direct laser writing is identified with reaching yield stress.

The design of vehicle impact zone is of great significance for passive safety protection of trains. This study introduces a novel design method of impact zone based on the concept of linear impact ...

The paper presents data on the involvement of local populations of bank vole (Clethrionomys glareolus) in the biogeochemical cycles of Cu, Zn, Cd, and Pb at territories strongly chemically polluted by large nonferrous metallurgical plant in the Middle Urals (in 1990–1992) and after a significant decrease in its emissions (in 2015–2017). At maximally polluted areas (impact zone), the animal-controlled transit Cu, Cd, and Pb flows approached their background values by the end of the study period, and the Zn flow simultaneously twofold decreased compared to the background areas. At moderately polluted areas (buffer zone), no significant changes in the metal fluxed were detected for any of the elements. The specifics of the transit flows of the elements at variably polluted areas are controlled by the concentrations of these elements in the diet of the animals and by the abundance of voles. Thereby the manyfold (fifty-fold) decrease in the emissions did no result in an equivalent decrease in the concentrations of the metals in the animal rations at the polluted areas. The main reason for the changes was a structural transformation in the community of the small mammals, which led to a drastic decrease in the bank vole population in the impact zone. The simultaneous effects of the analyzed factors over the study period of time (25 years) resulted in intensification (in the background zone), retardation (impact zone), and stabilization (buffer zone) of the biogeochemical exchange of the elements.

Influence of laser pulse treatment on structural state and strength characteristics of subsurface layer in Armco iron has been investigated. The yield stress of this layer was estimated from structural characteristics observed experimentally. The yield stress was shown to depend on the degree of ultra-fine and nanoscale grain refinement and the density of dislocations. The correlation between the degree of hardening and dislocation density in the laser impact zone was established.

Perfluorooctanoic acid (PFOA) was used as a fluoropolymer manufacturing aid at a fluoropolymer production facility in Parkersburg, WV from 1951 to 2013. The manufacturer introduced a replacement surfactant hexafluoropropylene oxide dimer acid (HFPO–DA) that has been in use at this site since 2013. Historical releases of PFOA and related epidemiological work in this area has been primarily focused on communities downstream. To provide an update on the ongoing impacts from this plant, 94 surface water samples and 13 soil samples were collected mainly upstream and downwind of this facility. PFOA was detected in every surface water sample with concentrations exceeding 1000 ng/L at 13 sample sites within an 8 km radius of the plant. HFPO–DA was also found to be widespread with the highest levels (>100 ng/L) found in surface water up to 6.4 km north of the plant. One sample site, 28 km north of the plant, had PFOA at 143 ng/L and HFPO–DA at 42 ng/L. Sites adjacent to landfills containing fluorochemical waste had PFOA concentrations ranging up to >1000 ng/L. These data indicate that downwind atmospheric transport of both compounds has occurred and that the boundaries of the impact zone have yet to be fully delineated.

On the Kola Peninsula, peat bog soils and Al–Fe-humus podzols (according to the WRB classification, Cryic Ombric Fibric Histosols and Folic/Histic Albic Podzols, respectively) are the most common. However, comparison of their level of pollution with heavy metals (HM) has never been carried out. The purpose of this work is a comparative analysis of the level of HM pollution of the upper horizons of peat bog soils and Al–Fe-humus podzols in the impact zone of the copper-nickel plant. Soil testing was carried out in 37 closely located habitats (forest and swamp) situated in the zone of atmospheric emissions of the Severonickel plant (Murmansk region). The total content of Ni and Cu in soil samples was determined by atomic absorption spectrometry after their dissolution in a mixture of concentrated acids HNO3 and HCl. Statistical analysis of the soil analysis results was carried out in Statistica 12 using nonparametric Kruskel – Wallis, Mann – Whitney and Wilcoxon tests. It was established that both types of studied soils did not significantly differ in the total content of HM in the upper horizons of the soil profile. The level of pollution of compared soils is determined by the distance from the source of pollution, the rose of the prevailing winds and the orography of the terrain. The Ni content in almost all soil samples exceeds the Cu concentration, which is due to the excess of atmospheric emissions of technogenic Ni compounds compared to the content of Cu compounds in them. The phytotoxicity of both types of studied soils varies widely: from its complete absence to a high and very high degree. At the same level of soil pollution with HM swamp habitats are more prosperous due to better moisture content of peat bog soils.

Among residents of the Bryansk and Gomel regions of Russia and Belarus, who were exposed to the so-called “iodine attack” as a result of the 1986 Chernobyl Nuclear Power Plant accident, there was a sharp increase in thyroid disease. Therefore, the natural iodine deficiency in soils was an important additional risk factor that could cause adverse reactions primarily among children, for whom the incidence of thyroid cancer in Belarus increased by 76 times. Potatoes belong to one of the main ration-forming foods for local population. In this regard, in 2007–2017, 97 settlements were surveyed in the affected areas, in which samples of local arable soils and potatoes were taken from 138 private subsidence farms (PFs).The iodine content in the studied soils of the private farms of the Bryansk region ranged from 0.11 to 3.5 mg/kg (air-dry weight). The content of iodine in potatoes grown on these soils varied within a considerably wider interval: from 0.002 to 0.119 mg/kg (wet weight), averaging 0.033 mg/kg, which indicates a generally low iodine transfer to this particular product. The data obtained deserve attention when organizing monitoring and carrying out measures for the prevention of iodine deficiency.

Selective Laser Melting (SLM) – as one of a number of additive manufacturing techniques – is a promising method for the manufacturing of complex structures and may bring about significant improvements in the context of custom-made designs and lightweight constructions. However, the complex multiphysical processes occurring during SLM necessitates the establishment of appropriate constitutive and process models in order to quantitatively predict the properties of the final workpiece. In particular, the accurate determination of process-induced eigenstresses is a challenging yet important task. In this work, a constitutive modelling framework stemming from phase transformations in shape memory alloys is adopted to the modelling of the changes of state during SLM. This model is based on energy densities and energy minimisation in general and specifically serves as a basis for further enhancements such as the consideration of multiple solid phases of the underlying material. This is particularly considered important due to the fact that the cooling rates during SLM are heterogeneously distributed and that thus different solid phases may form out of the molten material pool. As a first step, the present overall model comprises three phases of the material, namely powder, molten, and re-solidified material. The thermomechanically fully coupled Finite-Element-based process model incorporates approaches for, e.g., the laser beam impact zone and the layer construction model.

The Nypa fruticans Wurmb (Nypa), a true mangrove palm, is abundant in the Sundarbans reserved forest of Bangladesh. Leaves are the primary product obtained from the Nypa, which are often used as thatching materials and source of income for the forest-dependent communities in the Sundarbans Impact Zone (SIZ) of Bangladesh. Hence, this study aimed to assess the usefulness of the Nypa leaf collection as a livelihoods strategy in the SIZ of Bangladesh. A total of 90 Nypa leaf collectors from three coastal unions were interviewed by administering a semi-structured interview schedule. Effects of social factors [age, education level and household (HH) members involved in income generation] and economic factors (primary, secondary and tertiary occupation) on the HH total income of the Nypa leaf collectors were analyzed using linear regression and Pearson’s correlation, respectively. Moreover, the effect of physical factors on the HH total income was analyzed by ANOVA and linear regression. Results suggested that income from the Nypa leaf collection, though making only a quarter percent of HH total income, was constrained by underdeveloped infrastructure, inaccessibility to fair market price, limitations of financial capital and frequent attack of Royal Bengal tiger (Panthera tigris tigris). The study, therefore, suggests that Nypa leaf collection from the Sundarbans alone could not be a sustainable livelihoods strategy for the forest-dependent communities in the SIZ of Bangladesh. Diversified and advanced husbandry activities, which have the potential to further reduce dependency on forest resources, would strengthen the livelihoods strategy and ultimately conserve the resources of the Sundarbans.

Disperse and chemical composition and morphometric-mineralogical peculiarities of dust from Trypilska thermal power plant (TPP) fly ash were investigated. Analytical data are analyzed regarding the content of suspended particles from the air within the influence zone of TPP (10 km). As a research material we used dust picked up from the air and leaves of Amaranthus. According to the study results, it was found that suspended particles undifferentiated by composition are mainly finely divided (less than 10 μm) fractions of silicates (aluminosilicates), sulfur crystals (sulphides, sulfates), zirconium oxides with copper, sodium, potassium, calcium, magnesium, sulfur, chlorine, single phos-phorus inclusions and fluoride. The shape of the dust particles is predominantly conglomerate-like with the adherence of fine particles of different shapes from a perfectly spherical to a fragile with sharp edges. The content of silicon dioxide in the chemical composition of the dust reaches 70-20%. The presence of zirconium and "reactive silica" in the content of the researched dust confirms its mainly man-made genesis. After all, "reactive silica" (Si–) can only be formed as a result of high-temperature processing of quartz particles. Quartz aerosol particles formed during combustion of coal, actively interact with gases, acids, heavy metals with the formation of "quartz microcontain-ers", carrying toxic substances. Getting into the human body, particles of quartz bring on its surface compounds that are strong toxins, carcinogens and mutagens. Acute fragments of quartz crystals cause mechanical damage to the tissues of the body. The dust fly ash from Trypillya TPP represents a significant environmental hazard for the population and vegetation of the 10-km zone. Inhalation of the dust by a person causes the development of respiratory diseases, namely: fibrosis, granulomas, silicosis. Deposition of the ash dust on the surface of the leaves leads to the drying of the plant because the biologically active silicon in the dust leads to the formation of calcium silicate mi-crostalagmites in the tissues of leaves that overlap the stomata.

We rely on a policy experiment in the New York City Police Department (NYPD) to address the well-known problems of omitted variable bias and infra-marginality in traditional outcomes tests of racial bias in police stops. The NYPD designated specific areas as impact zones and deployed extra officers to these areas and encouraged them to conduct more intensive stop, question, and frisk activity. We find that the NYPD are more likely to frisk black and Hispanic suspects after an area becomes an impact zone compared to other areas of the city.