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Number of results: 12
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Abstract

StreszczenieMetaepistemologiczny projekt Kazimierza Ajdukiewicza zwany „semantycz-n4 teorią poznania” postuluje, aby podchodzić do poznania od strony języka. Projekt ten zarazem uzasadnia ów analityczny postulat, wykazując, ze jeśli poznanie ma bye określone co do treści, to do poznania tak właśnie powinno się podchodzić. Podejście to pojmuje poznanie jako twór, na który składają się językowe znaczenia wyrażeń. Takie pojmowanie poznania posiada tę zaletę iż pozwala wykorzystać w epistemologii rezultaty uzyskane w metamatema-tyce do rozwiązywania pewnych tradycyjnych sporów epistemologicznych. Projekt formalnej teorii poznania przedstawił Roman Suszko. Inspiracją tego projektu była semantyczna teoria poznania Kazimierza Ajdukiewicza, której Roman Suszko nadal postać sformalizowaną. Kontynuatorem formalnoepiste-mologicznych badah Suszki jest Jan Wolehski. Pytanie, które autor artykułu stawia i na które udziela odpowiedzi, brzmi: jakie warunki winny bye spenio-ne, aby można było przejsc od klasycznej (subiektywnej) teorii poznania do teorii poznania rozumianej semantycznie, a w szczególności do jej sformalizo-wanej postaci, i aby zarazem wyniki uzyskane na gruncie semantycznej teorii poznania były równoważne wynikom uzyskanym na gruncie teorii poznania pojmowanej klasycznie?
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Abstract

This paper recapitulates Polish botanical and mycological research on terrestrial and freshwater Antarctic ecosystems carried out between 1977 and 2009. The main results are briefly summarized. The references encompass nearly 200 papers on floristics, taxonomy, biogeography, ecology, cytology, bioc hemistry, physiology and genetics of lichens, mosses, fungi, algae and vascular plants inhabiting soils, rocks and inland waters in the Antarctic.
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Abstract

The paper describes anatomical and physiological features of photobionts and mycobionts in Bryoria forsteri Olech & Bystrek, Caloplaca regalis (Vain.) Zahlbr., Cetraria aculeata (Schreb.) Fr., Ramalina terebrata Hook f. & Taylor, Sphaerophorus globosus (Huds.) Vain. and Usnea antarctica Du Rietz, collected in the Antarctic under varied weather conditions. Green algae from the genera Lobosphaera and Trebouxia were gathered in depressions of the cortex under the more resistant mycobiont hyphae. In photobiont cells a large amount of highly osmiophilic electron-dense PAS-negative material, lipid-like in character, was of particular interest. Similar material also filled certain areas of the aerial apoplast. A star-shaped chromatophore with central and lateral pyrenoids encompassed most of the photobiont protoplast in all the studied species. Regularly arranged thylakoids with evenly widened lumina along their entire length and osmiophilic lipid droplets adhering to their outer surfaces were visible within the pyrenoid. Inside the chloroplast, large protein inclusions tightly joined with the thylakoids were observed. The mycobionts were closely attached to each other another and with the photobionts by means of an outer osmiophilic wall layer, and formed intramural haustoria. Their protoplasts were filled with PAS-positive polysaccharides and a large amount of lipid-like substances. The photobionts were physiologically active and produced a large amount of electron-dense osmiophilic material, and PAS-positive starch grains were visible around their pyrenoids in the thalli collected in different weather conditions. The permanent reserves of nutritive materials deposited in the thalli enable these organisms to quickly begin and continue indispensable physiological processes in the extreme Antarctic conditions.
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Keywords lichenologia

Abstract

O wyboistych dla kobiety polarnych ścieżkach, wyjątkowości porostów i sztuce spełniania marzeń mówi prof. zw. dr hab. Maria A. Olech z Zakładu Biologii Antarktyki Instytutu Biochemii i Biofizyki Polskiej Akademii Nauk.
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Abstract

This paper offers a comparison of Muriella decolor specimens from different geographical regions and habitats (limestone caves in Poland and ice denuded areas near the Ecology Glacier, King George Island, South Shetland Islands, West Antarctic). Morphological and cytological variability, ecology and life strategies of M. decolor were studied in fresh samples, and also in cultures grown on agar plates. The complete life cycle, with de − tailed ultrastructural (LM and TEM) analysis are presented. The electron microscopic observations prove that materials identified as M. decolor collected in Poland and the Antarctic have distinct ultrastructural features. These include the chloroplast lamella arrangement, mitochondrial cristae structure and the cell wall thickness.
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Abstract

During three austral summer seasons cargo, expeditioner clothes and equipment of the Polish Antarctic Expedition were examined for the presence of alien propagules. Detailed inspections were undertaken at the station buildings, searching for any invertebrates. During each austral summer fresh fruits and vegetables were also inspected. A total of 359 invertebrates and their remains were found in cargo transported to Arctowski Station, or caught in the station’s facilities. The majority of samples were classified as cultivation pests (26%), food pests (43%), wood−destroying pests (4%), domestic insects and arachnids (15%). Through supply of the research station a wide range of alien organisms can be accidentally transported and ultimately introduced to the Antarctic. This study has clearly demonstrated that almost all cargo items can be a potential vector for alien organisms. Species from a broad range of biological groups can be transported to the Antarctic and remain in a viable state.
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Abstract

During three austral summer seasons, dust and soil from clothes, boots and equipment of members of scientific expeditions and tourists visiting the Polish Antarctic Station Henryk Arctowski were collected and analysed for the presence of fungal propagules. Of a total of 60 samples, 554 colonies of fungi belonging to 19 genera were identified. Colonies of the genus Cladosporium , Penicillium and non−sporulating fungus ( Mycelia sterilia ) dominated in the examined samples. The microbiological assessment of air for the presence of fungi was also conducted at two points in the station building and two others outside the station. A total of 175 fungal colonies belonging to six genera were isolated. Colonies of the genus Penicillium were the commonest in the air samples. The potential epidemiological consequences for indigenous species as a result of unintentional transport of fungal propagules to the Antarctic biome are discussed in the light of rapid climate change in some parts of the Ant − arctic and adaptation of fungi to extreme conditions.
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Abstract

Diatom assemblages from small pools and creeks on the Ecology Glacier forefield have been investigated. It is the first study in the Admiralty Bay region after the thorough taxonomic revision of the non-marine Antarctic diatom flora. A total of 122 diatom taxa, belonging to 35 genera were identified. More than 55% of all observed species have a restricted Antarctic distribution. Another 15% have a marine origin. Nitzschia gracilis Hantzsch, N. homburgiensis Lange-Bertalot and Planothidium rostrolanceolatum Van de Vijver et al. dominated the flora. Based on a DCA analysis, samples were subdivided in three groups reflecting ecological differences. Several samples (group 1) showed a mixed freshwater/marine diatom composition and are typical for coastal pools. Two other groups were separated based on the amount of limnoterrestrial taxa indicating the temporary character of some of the pools.
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