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Abstract

Chlorophyll a content and the density and species composition of algae were determined in drifting sea ice north of the Elephant Island (between 54-56°W and 60°30'—61°00'S) at the end of October 1986. In yellow-brownish pieces of brash ice the amount of chlorophyll α was on average 203.5 ± 149.9 mg m-3 at the density of algal cells of 255.7+137.8-103 in cm3. In not visibly discoloured ice the respective values were about 80 times lower, and in surface water about 700 times lower. 69 algal taxa were recorded in the samples, almost all of which were diatoms. Nitzschia cylindrus dominated in all the samples. A comparison of species composition in the investigated habitats revealed that the highest species similarities occurred between samples collected in discoloured ice, lower in the uncoloured ice and the lowest ones in water.

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Authors and Affiliations

Ryszard Ligowski
Maciej Lipski
Krzysztof Zieliński
ORCID: ORCID
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Abstract

Thermoluminescence datings of glacial and marine sediments from Sörkapp Land, southern Spitsbergen enabled to limit the Late and Middle Pleistocene glacial events in this area. Sediments of raised beaches at 15—18, 30—38 and 42—56 m a.s.l. in Breinesflya were TL dated for 63, 68 and 87 ka respectively. Four other dates from Lisbetdalen, Slaklidalen and Sergeijevskardet proved two glacial advances during the Sörkapp Land ( = Wiirm) Glaciation. named the Lisbetdalen Stage (47 and 41 ka) and the Slaklidalen Stage (28 and 22 ka). Glacial sediments on slopes of Gavrilovfjellet and Strupryggen were dated for 141 and 217 ka respectively. These dates prove the glaciers of the Wedel Jarlsberg Land (= Riss) Glaciation occupied a considerably larger area in southern Spitsbergen than the glaciers of the following Sorkapp Land Glaciation.

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Authors and Affiliations

Jerzy Butrym
Leszek Lindner
Leszek Marks
Ryszard Szczęsny
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Abstract

Transport properties of bronchial mucus are investigated by two-stage experimental approach focused on: (a) rheological properties and (b) mass transfer rate through the stagnant layer of solutions of mucus components (mucine, DNA, proteins) and simulated multi-component mucus. Studies were done using thermostated horizontal diffusion cells with sodium cromoglycate and carminic acid as transferred solutes. Rheological properties of tested liquids was studied by a rotational viscometer and a cone-plate rheometer (dynamic method). First part of the studies demonstrated that inter-molecular interactions in these complex liquids influence both rheological and permeability characteristics. Transfer rate is governed not only by mucus composition and concentration but also by hydrophobic/hydrophilic properties of transported molecules. Second part was focused on the properties of such a layer in presence of selected nanostructured particles (different nanoclays and graphene oxide) which may be present in lungs after inhalation. It was shown that most of such particles increase visco-elasticity of the mucus and reduce the rate of mass transfer of model drugs. Measured effects may have adverse impact on health, since they will reduce mucociliary clearance in vivo and slow down drug penetration to the bronchial epithelium during inhalation therapy.

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Authors and Affiliations

Marcin Odziomek
Martyna Kalinowska
Aleksandra Płuzińska
Antoni Rożeń
Tomasz R. Sosnowski

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