The aim of the research was to explore a new locality of Galeopsis angustifolia (Lamiaceae), a rare taxa in Poland. The floristic composition of a plant community with G. angustifolia was determined. The species was recorded along the railway line from Pyrzyce to Stargard Szczeciński, near to the railway station in Okunica village, not used since 2004. Currently, the plant community with G. angustifolia occupies a transect >300 m in length. It is also sporadically found in the areas adjacent to the railway line. The species penetrates into ruderal communities from the Artemisietea vulgaris class and creates plant communities with Galeopsis angustifolia, a dominant species in the patches. Synanthropic species, e.g., Rubus caesius, Convolvulus arvensis, Senecio viscosus, meadow species, e.g., Arrhenatherum elatius, Potentilla reptans, Pastinaca sativa, and mosses of dry and rocky habitats also form plant communities with Galeopsis angustifolia. Keywords rare species; Galeopsis angustifolia; railway areas; plant communities IntroductionRailway lines create specific environmental and soil conditions for plant growth. Species growing in these biotopes have distinctive ecological features; they are tolerant to excessive light, temperature fluctuations, resistant to the strong effect of precipitation, frost, erosion, wind, and air movement initiated by passing trains [1]. Despite harmful abiotic factors, railway lines create a habitat for many plant species from different ecological groups. Wildlife developed along railway lines has been the object of interest of many naturalists for many years. A lot of attention has been dedicated to flora growing in railway areas [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], including rare and protected plant species growing along railway embankments [22][23][24][25]. Galeopsis angustifolia from Lamiaceae is one of the rare species that grows in railway habitats in Poland [26,27].Galeopsis angustifolia (Ehrh.) Hoffm. is an annual plant with a height of 10-40 cm and a grey-hairy stem, without firm bristles near the nodes. It is characterized by lance-shaped or narrow lance-shaped leaves and by entire or softly corrugated leaf margins with 4 pairs of teeth at the most. The flowers are small (15-25 mm), with a red-violet perianth, gathered in pseudo-whorls. The calyx is very hairy, usually without glands, with visible veins in the lower parts and three times shorter than the corolla. The fruit is an ovoid nutlet which contains numerous seeds. It blooms from June till October [28,29]. According to the ecological indicator values, this species prefers warm regions and microhabitats (T = 5-4), and it grows in full light (L = 5). It is adapted to dry places (W = 2), rich in calcium carbonate (R = 5), poor in nutrients (Tr = 2) and organic matter (H = 2), scree and gravel [27].

Asclepias syriaca L. is on the invasive species list in Poland. Its sites are scattered, with the exception of cultivation sites; they are also not well identified in the country and that is why they have not been presented in the ATPOL (Distribution Atlas of Vascular Plants in Poland) yet. In this study, spatial structure of A. syriaca population against phytocenotic and soil conditions in Widuchowa (West Pomerania) were examined. Number of specimens, their density per 1 m 2 , and mean crowding were determined. In addition, the population spatial structure type was identified through observations and by calculation of the dispersion coefficient. On the basis of the conducted research, it was found that the investigated population comprised 1 500 specimens and occupied the area of 38 m 2 . It exhibited regular spatial distribution type (dispersion coefficient<1) and was characterized by high value of mean shoot density, which amounted to 29 spec./1 m 2 (max. 35 spec./1 m 2 ). On the basis of the conducted chemical analysis of the soil from the A. syriaca habitat, the substrate was classified as alkaline soil (pH=7.3-7.6), of low total nitrogen (0.07-0.15%), as well as low total carbon content (0.8-1.45%).

Gaucher disease is a lysosomal storage disorder caused by deficiency of human acid beta-glucosidase. Recent x-ray structural elucidation of the enzyme alone and in the presence of its inhibitor was done, which provided an excellent template for further studies on the binding of substrate, product and inhibitor. To draw correlations between the clinical manifestation of the disease driven by point mutations, L444P and L444R, and the placement and function of putative S-binding sites, the presented theoretical studies were undertaken, which comprised of molecular dynamics and molecular docking methods. The obtained results indicate the D443 and D445 residues as extremely important for physiological functionality of an enzyme. They also show, although indirectly, that binding of the substrate is influenced by an interplay of E235 and E334 residues, constituting putative substrate binding site, and the region flanked by D435 and D445 residues.