In this article Author discusses the problem of false interpretations of the earliest history of the Slavic people undertaken by Polish 19th century historians. He also analyses the attitude of various historians towards their colleagues' forgeries.

In the paper the model of the disturbing potential based on the lower-degree harmonic spherical polynomials and the local density model of topographic masses has been proposed. Topographic masses are represented by DTM. The model parameters are fixed by the use of quasigeoid heights as well as a dense network of gravity points. Preliminary analyses of the model's robustness of gravimetric data errors have also been included.

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) may be formed during combustion of Diesel and gasoline rud and may be produced in gas-phase reactions of polycyclic aromatic hydrocarbons (PAHs) with oxides of nitrogen. These compounds can form a significant fraction olthc mainly direct-acting mutagenie compounds present in extracts of ambient air particles. Using own analytical method of nitro-PAHs determination, concentrations or total PAHs, nitro- and dinitro-PAHs in urban and non-urban area of three cites of Upper Silesia in Poland were measured. The dependence between concentration of PAHs and nitro-pAHs in urban and non-urban area as well as their distribution depending on roadway distance were searched. The study showed a significant influence of road transport on the levels ofnitro-PAHs concentration.

The study area of the Nida valley was examined to investigate variations in groundwater and surface water levels, as well as the interaction between them. In the valley, there were three branches. The two actives were the Nida River itself and the Smuga Umianowicka branch while the Stara Nida branch was dry during the measurement session. Over a 12-month period from June 2021 to June 2022, 7 monitoring points were equipped with piezometers, comprising 5 groundwater points and 2 surface water points. The monitoring frequency was set to 30 minutes. The results of this research indicate that there are significant differences in the water level at the same observed point at different times. This study demonstrates seasonal changes in both surface water and groundwater levels with higher levels in autumn and winter and lower levels in spring and summer, which are closely tied to the changes in meteorological conditions during the research period, such as precipitation and air temperature. The study results also indicate that during summer and winter at the Nida River and its riparian area, losing stream is the primary process occurring in the studied reach. Conversely, during autumn and spring, the main process is gaining stream. At the human-maintained Smuga Umianowicka branch and in its riparian area, losing stream is the main process during summer and autumn, and gaining stream is the main process during spring. During winter, losing stream and gaining stream processes can occur simultaneously, and neither process takes place mainly.

We have presented dielectric and conductivity studies of two liquid crystal (LC) compounds- p-octyloxybenzoic acid (8OBA) and p-decyloxybenzoic acid (10OBA). Dielectric permittivity study of those compounds gives the evidence of space charge polarization and ionic conductance in the samples. Dielectric permittivity is found to be the highest for 8OBA than 10OBA. Both compounds found to exhibit positive dielectric anisotropy. Splay elastic constant as a function of temperature has also been investigated. Frequency and temperature dependent electrical conductivity of these two LC compounds have been studied in detail. Activation energy has been estimated from both dc and ac conduction process.