The study was carried out to investigate the interactive effects of exogenous melatonin and excess amounts of zinc and copper on the growth and physiological parameters, antioxidant defense system and nutritional balance of cannabis seedlings. Cannabis sativa L. plants, grown under a completely randomized design, were irrigated with complete Hoagland’s nutrient solution. CuSO ₄ (0, 50 and 150 µM) and ZnSO ₄ (0, 50 and 100 µM) and their combinations were supplied to 21-day-old seedlings for 2 weeks. During the second week, melatonin was added to the nutrient solution at 100 μM. Zn and Cu stress led to reduced growth and physiological parameters, it promoted oxidative stress, changes in antioxidant enzymes activity and imbalance of mineral nutrients in cannabis seedlings. However, melatonin alleviated the growth retardation and physiological disorders of seedlings under normal conditions and heavy metal stress. The content of reduced glutathione and the activity of antioxidant enzymes such as glutathione reductase and ascorbate peroxidase were improved by melatonin. Excess amounts of zinc and copper changed the pattern of nutritional elements distribution in cannabis seedlings. Cu and Zn caused reduced content of Fe, Ca and K ions in shoots and roots. Melatonin treatment was able to adjust the nutrients content in metal-stressed seedlings up to the level of the control. Exogenous melatonin reduced toxic levels of Cu and Zn in seedlings overloaded with copper and zinc. MT also raised K, Ca and Fe concentrations in roots and shoots of seedlings under stress. Our results support the idea that melatonin acts as a powerful antioxidant, it can also be considered as a potent regulator of ion homeostasis in cannabis seedlings under heavy metal toxicity. Further studies still need to investigate the alleviatory effects of melatonin under field conditions.

The investigation described herein discusses the morpho-anatomical characteristics of xylem parenchyma cells of European ash stems undergoing heartwood formation. The research material comprised of cross and radial sections of wood obtained from stems at breast height of 91-year-old ash trees, half of which had visible ash dieback symptoms. The radial section of the wood samples was stained with acetocarmine to detect nuclei and with I2KI solution to observe starch grains in parenchyma cells, both of radial and axial systems. Additionally, microscopic slides were stained with Alcianblue Safranin-O, and fluorescence microscopy was applied to detect lignified cell walls. The color of sapwood and heartwood distinctly differed – heartwood extracts were detected in approx. 47 rings. Most of the parenchyma cells had nuclei present in both wood zones. Also starch grains were detected in the majority of the tree rings of the researched samples. All of the xylem parenchyma cell walls of axial and radial systems were lignified. The research revealed that lignification, parenchyma cells death and the release of heartwood extracts are processes remote in time and space. Furthermore, parenchyma cell walls lignification did not figure as a sign of the upcoming parenchyma cells death. Based on the current research, ash dieback disease might slightly impact the development paths of parenchyma cells. Compared with scores reported for other trees, European ash parenchyma cells longevity is indeed remarkable.

This is the second part of an article featuring the Polish philatelic magazines published by the Polish Philatelic Association, its affiliates as well as other publishers. The article also discusses various projects aimed at the digitalization of the philatelic magazines and making the back issues available online.

This article discusses the theatre section in Gazeta Żydowska published under the control of the occupation authorities in the Generalgouvernement in 1940–1942. The paper focused first of all on theatres in the Warsaw ghetto. The news and reviews were to create the impression that Jewish culture was flourishing and the situation in ghetto was normalizing as the residents were adapting to the new conditions.

This article deals with a debate in the pages of the interwar press over a memorial landscape park opened in 1932 at Żelazowa Wola, the birthplace of Fryderyk Chopin. Designed by Franciszek Krzywda- Polkowski, the park provoked a flood of opinions and commentaries from contemporary cultural luminaries. The discussions raged mostly in literary periodicals as well as popular newspapers and magazines. The article attempts to reconstruct the narrative patterns of the debate around its two poles, represented by the admirers and opponents of Krzywda-Polkowski's innovative design.

This article looks at press studies of the newspapers and periodicals that have been published in Zielona Góra, beginning with the pre-1945 Grünberger Wochenblatt. A turning point in the history of the region's press studies was the publication in 2000 of Andrzej K. Piasecki's monograph Lubuska czwarta władza (Zielona Góra's Fourth Estate); it was followed by a historical survey of the press of the Gorzów Wielkopolski subregion by Krzysztof Wasilewski. While research is coordinated by the Cyrian Norwid Library (among others a co-sponsor of a volume titled Oblicza prasy Ziem Zachodnich 1945–2012), the periodical Zielonogórskie Studia Bibliotekoznawcze provides a platform for new work. The latest publication in the field is Jolanta Chwastyk-Kowalczyk's monograph Pro Libris. Czasopismo Literacko-Kulturalne; a study of the newspaper Gazeta Nowa is in progress.

Ecological themes have now become a major topic in children's books and magazines. In 2017–2021 the learn-and-play magazine Kukbuk Dzieciaki ( Cookbook Kids), aimed at educating a more aware and knowledgeable food consumer, also gave a lot of attention to the promotion of eco-friendly habits. The article analyzes the publisher's strategy of combining the didactic purpose ('saving the planet' and teaching good dietary habits) with the commercial side of his enterprise.