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The purpose of this paper is to estimate the influence of long‐term, whole‐body exposure of rats to strong, static electric field with physical parameters generated nearby high voltage direct current (HVDC) transmission lines on the intensity of reactive oxygen species generation analyzed indirectly, basing on the measurement of malone dialdehyde level, as well as on the activity of enzymatic antioxidant defence system.

In rats exposed to static electric field with intensity of 16, 25 and 35 kV/m, respectively, or sham‐exposed eight hours daily for 56 days, in the obtained plasma, erythrocytes lysates and liver homogenates the activity of some antioxidant enzymes as well as the concentration of malone dialdehyde were determined with use of spectrophotometric and kinetic methods.

It was observed that long‐term exposure of rats to static electric field causes only temporary compensatory changes in the concentration of malone dialdehyde and transient changes in the activity of enzymatic antioxidant system, both in blood and in liver tissue in the form of temporary inhibition of activity of most antioxidant enzymes during exposure cycle, with subsequent compensatory increase in this activity after the end of exposure cycle, enabling maintenance of prooxidant‐antioxidant balance in the organism of experimental animals and inhibition of peroxidation process.

Presented data indicate that construction of air HVDC transmission lines, according to actual compulsory regulations, enables serious health hazards related to persistent disturbances of prooxidant‐antioxidant balance to be avoided.

In the experiment it was confirmed, for the first time, that long‐term exposure to strong static electric field causes transient compensatory changes of prooxidant‐antioxidant balance in living organisms.

The aim of this paper is to find a fast-acting numerical model of the phase shifter.

The 3D FE model of the investigated unit is presented and compared with the results of the measurements. Due to its size, it is not suitable for transient analyses. The simplified 2D finite elements approach is discussed afterwards, with the identity of the magnetic energy stored in both models as the criterion of similarity between 2D and 3D models.

The introduction of scaling factors for the magnetic permeability values in particular volumes of the two-transformer set of the phase shifter enabled acceptable accuracy in calculations of the basic exploitation parameters of the phase shifter.

The developed methodology allows the analysis of the exploitation conditions of two separated transformers connected in a power grid inside the single finite elements model.

Although the numerical models of power transformers are extensively discussed in the literature, the usage of the equivalent fast 2D model for the representation of two cooperating transformers at load conditions was not published yet.

Changes in food retailing (globalization, concentration) have negative impacts on smaller, “traditional” food retail businesses. Their market share decreasing year by year. The purpose of this study is to examine and compare the financial performances of these businesses under the given circumstances and current economic environment in a Hungarian and a Romanian county.

The study is based on two complete databases, including all companies that behoove retail food activity (considering the NACE cod) in the counties of Hajdu-Bihar (Hungary) and Cluj (Romania). The database analyzed contains the financial statements for five consecutive years for 212 and 690 businesses. Databases were examined by the most typical financial indicators using the multivariate and univariate analysis of variance and the k-medoid cluster analysis methods.

The results of the analysis have shown that there are differences in the number of retail food companies in the case of two counties, both in number and in financial performance. Companies in Hajdú-Bihar county perform better in terms of financial ratios than those in Cluj county. The groups created by k-medoids cluster analysis are relatively well distinguished in the case of Hajdú-Bihar county, while the picture is much more mixed in the case of Kolozs county. However, it is also important to note that the companies analyzed should generally perform better to survive.

Among the limitations of the study, it is important to note that the findings are relevant only to the two counties examined. Another limiting factor is that quite several companies had to be excluded from the analysis due to missing data or outliers.

The study presents for the corporate decision-makers the current performance of the companies of the sector examined in the two counties. The results of the study highlight the business areas of concern in management. The findings show that they need to change this performance to strengthen their market position. We believe that it is not enough to complain about the expansion of the supermarket chains, but they should take appropriate actions to improve their situation. Based on the results of the study, it can be concluded that there is a need to improve the financial efficiency of retail food companies in both counties to survive in the long run. This improvement is essential because retailers can play an important role in smaller settlements and narrower residential environments.

Comparative analysis of retail food companies in similar counties in these two neighboring countries has not been conducted using complex financial analysis. The study revealed the common and/or individual characteristics of these companies.