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Abstrakt

Accurate estimation of soil permeability is crucial in many geotechnical applications. Empirical and theoretical equations based on soil particle size distribution (PSD) offer a fast and cheap way for preliminary estimation of permeability in granular soils, however the results obtained from various formulas available in the literature often show significant discrepancies. While several comparative studies on this topic have been published, no definite conclusions can be drawn on the performance of the predictive equations in comparison with in-situ permeability measurements. Many formulas require porosity or void ratio as input parameter, which is difficult to obtain for granular soil in-situ. In this study we applied 30 predictive equations to estimate permeability of sandy soil in an outwash plain deposit. The equations were divided into 5 groups, based on their structure and the required input parameters. Empirical formulas were used to estimate the expected in-situ porosity range. The obtained permeability values were compared to the results of in-situ permeameter measurements and pumping tests. Significant differences in the results and in their sensitivity to porosity were found between the 5 groups of methods. In general, simple equations which do not include porosity were in better agreement with measurements than the other groups.
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Autorzy i Afiliacje

Wioletta Gorczewska-Langner
1
ORCID: ORCID
Anna Gumuła-Kawecka
1
ORCID: ORCID
Beata Jaworska-Szulc
1
ORCID: ORCID
Rafael Angulo-Jaramillo
2
ORCID: ORCID
Adam Szymkiewicz
3
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, ul. Narutowicza11, 80-233 Gdansk, Poland
  2. Laboratoire LEHNA, 3, rue Maurice Audin, 69518 Vaulx-en-Velin, Franc
  3. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, ul. Narutowicza 11, 80-233 Gdansk, Poland

Abstrakt

A total of sixty five taxa of marine phytoplankton (diatoms, dinoflagellates, silicoflagellates and cyanoprokaryotes) were recorded in the transect from the cold region of the Antarctic (Weddell Sea) up to La Plata Bay, Argentine in the late austral summer (March 1989). Diatoms were the dominant group in a south-north transect from the Seal-Bay (Princess Martha Land, the Antarctic). Most of the phytoplankton species of the cold Antarctic region disappeared around 50°S where there is a steep water temperature gradient. The diatom flora declined in the regions of increasing temperature, i.e. between 60° and 50° S and was replaced by dinoflagellates of the genus Ceratium. Large centric diatom genera Corethron, Rhizosolenia, Chaetoceros and Dactyliosolen represented the most apparent phytoplankton part. The most common of the small centric diatom genera were Thalassiosira, Asteromphalus, Actinocyclus and Coscinodiscus, while several species of Navicula and Nitzschia were the most abundant pennate forms. The presence of a considerable number of freshwater pennate diatoms, characterized as indifferent in the halobion spectrum and mostly periphytic, might be attributed to survival strategies during their development on the floating coastal ice.

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Autorzy i Afiliacje

Athena Economou-Amilli
Josef Elster
Jiří Komárek

Abstrakt

The species diversity of the Bryozoa in Kongsfjorden was determined based on quantitative, depth-stratified (0-30 m) samples collected by SCUBA divers (1996, 1998). One hundred and one species and 16 varieties of the three orders Cyclostomata, Ctenostomata and Cheilostomata - are reported from Kongsfjorden. Ten species are presumably new. The bryozoan fauna of Svalbard is mainly represented by Arctic and boreal-Arctic species and varieties. The few amphiboreal and subtropical-boreal species found most likely reach their northern limit of distribution near Spitsbergen. The distribution of the Bryozoa within Kongsfjorden was determined by depth and location sampled. The number of taxa increased, generally, with depth and distance from tidal glaciers located in the inner fjord. Relative decreases in species number occurred at 15-20 m depth in the middle to outer fjord. This is most likely explained by a change of water mass properties, i.e. a transition from the surface water layer to deeper marine water.

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Autorzy i Afiliacje

Valentina I. Gontar
Haakon Hop
Andrey Yu. Voronkov

Abstrakt

Hans Georg Gadamer w swoich rozważaniach nad istotą hermeneutyki w szczególny sposób akcentuje rolę języka w poznaniu i rozumieniu świata. W artykule podejmowana jest próba znalezienia zastosowania hermeneutyki Gadamera w prowadzonych przez lingwistów badaniach nad językowym obrazem świata. Pierwsza część pracy poświęcona jest językowemu obrazowi świata (JOS) w lingwistyce, druga dotyczy zaś hermeneutyki Hansa Georga Gadamera. Trzeci rozdział, łączący tematykę dwóch poprzednich, odpowiada na pytanie stawiane jako cel pracy. Prezentowane tu rozważania mieszczą się w szerszej refleksji nad filozoficznymi podstawami badań lingwistycznych.
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Autorzy i Afiliacje

Zuzanna Sima
1

  1. Ośrodek Międzyobszarowych Indywidualnych Studiów Humanistycznychi Społecznych, Uniwersytet Jagielloński, Kraków, Polska

Abstrakt

We consider the Debreu private ownership economy in which all consumption plans belong to a proper linear subspace of the commodity-price space ℝl. This geometric property of consumption sets means that there is a dependency between quantities of some commodities in all consumption plans. Competitive mechanism makes producers adjust their plans of action to the same dependency. It results in the mild evolution of the production sector to offer production plans which are also contained in the given subspace of ℝl. Modified production system and the initial consumption system can form an economy in equilibrium. The aim of this paper is to model gentle changes of producers’ activity that give equilibrium in the Debreu economy with consumption system reduced to a proper subspace of ℝl without considering additional costs.

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Autorzy i Afiliacje

Agnieszka Lipieta

Abstrakt

Plants adapt to extremely low temperatures in polar regions by maximizing their photosynthetic efficiency and accumulating cryoprotective and osmoprotective compounds. Flowering plants of the family Poaceae growing in the Arctic and in the Antarctic were investigated. Their responses to cold stress were analyzed under laboratory conditions. Samples were collected after 24 h and 48 h of cold treatment. Quantitative and qualitative changes of sugars are found among different species, but they can differ within a genus of the family Poaceae. The values of the investigated parameters in Poa annua differed considerably depending to the biogeographic origin of plants. At the beginning of the experiment, Antarctic plants were acclimatized in greenhouse characterized by significantly higher content of sugars, including storage reserves, sucrose and starch, but lower total protein content. After 24 h of exposure to cold stress, much smaller changes in the examined parameters were noted in Antarctic plants than in locally grown specimens. Total sugar content and sucrose, starch and glucose levels were nearly constant in P. annua, but they varied significantly. Those changes are responsible for the high adaptability of P. annua to survive and develop in highly unsupportive environments and colonize new regions.
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Autorzy i Afiliacje

Irena Giełwanowska
Elżbieta Łopieńska-Biernat
Marta Pastorczyk
Krystyna Żółtowska
Robert Stryiński
Ewa Zaobidna

Abstrakt

Sens życia Jewgienija Trubieckoja (1863–1920) to jedno z ważniejszych dzieł renesansu religijno-filozoficznego w Rosji. Porusza kwestię wartości ludzkiego życia mimo oczywistości zła, przemocy i upadku moralnego. W tym celu rosyjski myśliciel odwołał się do filozofii wszechjedności i kategorii objawienia, przy czym to drugie rozumiał w sposób szeroki i wąski. W szerokim znaczeniu objawia się nieustannie wyższa sensowność (wszechjedność), dzięki czemu człowiek może poznawać i rozwijać się, natomiast w wąskim znaczeniu objawił się Jezus Chrystus, który w paschalnej tajemnicy odsłonił ludzkości najgłębszy sens życia. Każdy człowiek może przyjąć albo odrzucić treść objawienia. Przyjąć objawiony sens pomaga świadomość kolektywna, doświadczenie wspólnotowe, życie w Kościele, Eucharystia, wzajemna odpowiedzialność nie tylko za braci w wierze, ale także za całe stworzenie. W niniejszym artykule omówiono także kwestie objawienia naturalnego i objawienia w religiach niechrześcijańskich oraz warunków i specyfiki objawienia chrześcijańskiego.
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Autorzy i Afiliacje

O. Adam Trochimowicz OFMCap

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