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Number of results: 401
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Abstract

The chlorophyll a content was measured at 62 oceanographic stations. At each station samples were collected from eight standard depths between the water surface and 150 m. Integrated values (chlorophyll α mg/m2) are used in the presentation of the results and discussion. The recorded quantities of chlorophyll α were rather high, amounting to as much as 634 mg/m2. The areas with high chlorophyll a content (> 200 mg/m2) were located in the region of the Anvers Island and Brabant Island, on the shelf around Joinville Island and opposite the Antarctic Sound, close to Clarence Island and beyond the regions recommended in the BIOMASS-SIBEX programme to the east and south of the South Orkney Islands. In the acetonie extracts of photosynthetizing pigments large quantities of phytoxanthin were found using the TLC method, what precludes the use of the Lorenzen method for determination of chlorophyll α and its degradation products.
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Abstract

Results of an oceanographic survey along the edge of drifting pack ice in the area between Elephant Island and the South Orkney Islands are reported. The influence of sea ice on hydrological factors was very weak. It was not possible to develop oceanographic features characteristic for marginal sea-ice zones in the areas with well marked surface currents and dynamic hydrological conditions. The spatial distribution of chlorophyll was governed by water stability, although during our survey, areas with enhanced vertical stability could not be described in terms of a sea-ice edge influence.
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Abstract

In 1979 54 water samples were collected at two oceanographic stations located in Admiralty Bay. Ranges of seasonal changes were found for the values of ten parameters: water temperature, salinity, dissolved О, pH, the contents of PO4 , Si, NO2, NO3, chlorophyll α and plant carotenoids at six depths between surface and 400 m. Data for temperature and salinity showed the absence of distinct thermoclines or haloelines which reflects the very low stability of waters in the Bay. The concentrations of nutrients were high during the entire year and they were not limiting for phytoplankton growth. Only nitrates decreased distinctly during algal blooms. The high dynamics of waters in the Bay causes a lowering in the chlorophyll α content to a maximum of about 2 mg/m3. Oceanographic, hydrochemical and hydrological conditions in Admiralty Bay are typical for the Antarctic shelf waters in this geographical region.
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Abstract

Jerzy Jedlicki was one of the most prominent Polish historians, whose activity extended to more spheres of intellectual and public life. His works dealing, for instance, with Polish intelligentsia in the nineteenth century, have importantly contributed to Polish historiography and intellectual life. The pro memoria note focuses on Jedlicki as a lecturer, a historian with a widely-recognised output, and a political commentator. Although of expressly leftist views, Jedlicki remained open-minded for other ideological views and interpretations.
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Abstract

We talk to Dr. Maciej Jórdeczka from the PAS Institute of Archaeology and Ethnology in Poznań about archaeological surprises, Neolithic medicine and paying respect to our deceased.
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Keywords digital humanist

Abstract

Dr. Maciej Maryl, Head of the Digital Humanities Center and Deputy Director at the Institute of Literary Research, Polish Academy of Sciences, talks about the table where innovations are born, the limits of literariness, and Polish humanities projects that can conquer the world.
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Abstract

This paper discusses particular traits of historical thinking, including the role of the historian’s mentality in the perception of history.
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Abstract

Ore and non-ore mineralization in cracks filled with hydrocarbons in the dark grey Upper-Devonian limestone has been found in the Józefka quarry of Upper Devonian limestone and dolomite near the Górno village near Kielce at Holy Cross Mts. Poland. Hydrocarbons in the liquid form and iron and copper sulphides appears hear in the fault zone as joints filling. The wall rocks are impregnated by hydrocarbons giving them black color. Hydrocarbon impregnations appears also following the bedding planes The coexistence of ore mineralization and hydrocarbon suggests their common origin and migration from deep-seated sources, that may be the Silurian Ordovician or Lower to Middle Devonian black shales. The metallic-hydrocarbon compounds were suggested as metals carrier. Ore and non-ore mineralization in cracks filled with hydrocarbons in the dark grey Upper-Devonian limestone has been found in the Józefka quarry of Upper Devonian limestone and dolomite near the Górno village near Kielce at Holy Cross Mts. Poland. Hydrocarbons in the liquid form and iron and copper sulphides appears hear in the fault zone as joints filling. The wall rocks are spotty impregnated by hydrocarbons giving them black color. Hydrocarbon impregnations appears also following the bedding planes The coexistence of ore mineralization and hydrocarbon suggests their common origin and migration from deep-seated sources, that may be the Silurian Ordovician or Lower to Middle Devonian black shales. The metallic-hydrocarbon compounds were suggested as metals carrier.
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Abstract

Coarse-scale studies on chlorophyll a distribution in a region covering the Scotia Front zone showed an increased chlorophyll content and its deeper distribution at stations situated in the frontal zone. The sources of chlorophyll α were probably both the phytoplankton released from melting ice as well as spring bloom.
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Abstract

The aim of the article is a preliminary assessment of the possibility of using ATES (Aquifer Thermal Energy Storage) technology for the seasonal storage of heat and cold in shallow aquifers in Poland. The ATES technology is designed to provide low-temperature heat and cold to big-area consumers. A study by researchers from the Delft University of Technology in the Netherlands indicates very favorable hydrogeological and climate conditions in most of Poland for its successful development. To confirm this, the authors used public hydrogeological data, including information obtained from 1324 boreholes of the groundwater observation and research network and 172 information sheets of groundwater bodies (GWBs). Using requirements for ATES systems, well-described in the world literature, the selection of boreholes was carried out in the GIS environment, which allowed aquifers that meet the required criteria to be captured. The preliminary assessment indicates the possibility of the successful implementation of ATES technology in Poland, in particular in the northern and western parts of the country, including the cities of: Gdańsk, Warsaw, Wrocław, Bydgoszcz, Słupsk, and Stargard.
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Keywords fossilized bones

Abstract

Fossilized bones help scientists not only identify the age of rocks, but also to determine the ancient environment and climate in which ancient humans and animals once lived. One just needs to know the right methods to use.
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Abstract

Extensive efforts have been made for many years by the power generating industry to replace conventional solid and liquid insulation with synthetic materials. Those measures are aimed at increasing the load capacity, improved fire safety and extending transformer life during exploitation. Modern insulating materials include aramid fibre-based paper and insulating fluids made of synthetic and natural esters. The paper presents research results of the electrostatic charging tendency (ECT) of mixtures of fresh and aged mineral oil Trafo En with synthetic ester Midel 7131 and natural ester Midel 1204. The measurements were taken in a flow-through system using the pipes made of metal, cellulose and aramid paper. The influence of the liquid flow velocity, the type of material of the measuring pipe and the mixture content on the level of the streaming electrification current generation was determined.
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Keywords Antarctic fishes

Abstract

During austral summer of 1979 in the area of Elephant Island ten species of fish representatives of five families, were identified.
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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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Abstract

The results of the detailed seismoacoustic profilling (CSP, boomar) are presented. The investigation has been carried out in February 1985 and 1988 during two Geodynamical Expeditions organized by the Institute of Geophysics of the Polish Academy of Sciences. The boomar penetration of the caldera floor went down to 150 msec. Four seismoacoustic units of volcanic formations have been determined. The unit A corresponds to pre-caldera series and occurred only in the border part of the flooded caldera. The unit contains mainly pyroclastic rocks (consolidated agglomerates and tuffs) and probably some intercalations of lavas. The units B, C and D fill up the caldera bottom and correspond to post-caldera series. The units are composed of pyroclastic rocks, containing also materials redeposited by lahars, glaciers, landwaters and by wind. The units C and D (the youngest one) were certainly deposited under water. All the units are cut by numerous faults, vents and other types of intrusions. The larger faults, en echelon type, are situated around the bottom and form a ring-fracture. Caldera was formed by succesive stages of collapsing. This process is not finished yet and volcanic activity is still alive (especially in the western part of the flooded caldera).
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Abstract

On the ground of results obtained by the seismoacoustic profiling carried out in 1985 and primary examination of core samples the following main seismoacoustic units are distinguished and characterized: unit A — bedrock, unit B — till and/or compacted glaciomarine deposit, unit C — glaciomarine ice-front deposit, unit D — glaciomarine mud. These results enabled to present the distribution of seismoacoustic units along the fiord and its extension on the shelf, as well as to determine a relation of bottom structures to Late Vistulian(?) deglaciation and the action of Holocene tributary glaciers, probably during the Little Ice Age. The position of marginal structures corresponding to local retreat stages of the glacier front is also presented.
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Abstract

A sea floor investigation was performed in the fiord of Hornsund by means of the seismoacoustic profiling, echosounding and core sampling. The main seismoacoustic sea floor units were recognized (the methods used according to Kowalewski et al. 1987a) and characterized on the basis of their relations to geomorphology and geological evolution. The bathymetrical sketch and the resulting geomorphological description of the bottom were prepared. The surface of the sea bottom and the surface of the bedrock displayed an irregular high relief with large sills dividing the fiord sea floor into several basins. Four main types of the sills were distinguished: burried sills, accumulative sills, rock sills and rock-accumulative sills. Within the internal Basins I and II there were thick (up to 170 m) covers of the glaciomarine ice-front deposit with changing thin ( 1 -5 m) blanket of the glaciomarine muds at the bottom surface. The Basin III had a cover of the glacial and glaciomarine deposits of variable lithology, genesis and age. The most external Basin IV had a cover o f glaciomarine muds up to 4 0 - 5 0 m thick, deposited on the tills. Four main glacial episodes were recognized, most probably referring to the stadials of Lisbetdalen, Slaklidalen, Revdalen and to the Little Ice Age.
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Abstract

Typically applied static (i.e. non-agitated) cultures do not provide sufficient conditions for efficient propagation of suspended non-adherent cells, in general. Feasibility of small-scale wave-type agitated single-use bioreactors for gentle agitation underlies applicability of such systems for scaling-up of fragile biomass of animal cells. The basic aim of the study was to compare the results of non-adherent HL-60 cell propagation performed referentially as the batch culture in typical static (i.e. non-agitated) disposable culture flasks (50 cm3 of culture medium) and in ReadyToProcess WAVETM25 bioreactor system (GE Healthcare) equipped with disposable culture bag (300 cm3 of culture medium) subjected to continuous wave-type agitation. The density and viability of HL-60 cells were significantly higher for the bioprocess subjected to wave-type agitation, than in the reference static culture. The values of the specific rate of glucose consumption per cell (rglc=cell) exhibited by HL-60 cells maintained in the system with continuous wave-type agitation was significantly lower (i.e. up to more than 42%) than the values noted for the static culture, for exactly the same time-points of two compared cultures. The results of the studies undoubtedly and comprehensively confirmed the applicability of the studied disposable bioreactor with wave-induced agitation as the right platform for proceeding the propagation of non- adherent HL-60 cells and for providing the culture conditions required by HL-60 cells for sustainable metabolism.
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Abstract

Certain chemical parameters such pH, specific electric conductivity (SpC) and concentrations of chloride ions (Cl-) have been analysed in samples of precipitation collected close to the Polish Polar Station at Hornsund (PPS), SW Spitsbergen. On the basis of seasonal data from years 1993-1994 and 1998-1999, some differences are apparent from the two sets. There is also a marked difference in the seasonal results, especially with respects to pH values; summer precipitation (pH of which can be as low as 3.78) is much more acidic than winter. This was particularly notable in respect of the summer of 1993, and was presumably the result of a relatively unusual atmospheric circulation and a high influx of airborne contaminants from Europe. The wide variation in specific electrical conductivity measurements is considered to be related to variations in wind direction and speed. That precipitation the highest total dissolved salts, of 11.7 mm w.e. (water equivalent), (November 1993), provided 10.7 g of salt per square metre of tundra near the Polish Polar Station. The proximity of the sea, consequently the development of marine aerosols, largely determines the chemical nature of the precipitation. Thus, variations in the chloride ion concentrations during the study periods more or less reflect the variations in the marine aerosol influences on the nature of the polluted precipitation. An analysis of the atmospheric circulation reveals that the most acid precipitation occurs most frequently in the C-8 type of circulation (cyclonic S + SW) and also, less so, for type C-3 (anticyclonic S + SW).
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Abstract

Measurements of CO2 concentrations in soil air were taken in the summer seasons of 1998 and 2001 in SW Spitsbergen. The measurements were carried out in three small non-glaciated catchments in the Hornsund region close to the Polish Polar Station. The preliminary measurements were made using a Dräger's pump and ampules which contained an alkaline absorbent (1998). Later (2001), a new more accurate apparatus which uses a gravimetric method was tested. A variety of different geographical situations was chosen for the CO2 measurements. These included areas which differed in respect of the local hydrology, terrain relief, exposure to solar radiation, distance from the sea and quantity of seabird excrements in the soil. The measured concentrations of soil CO2 varied between 0.05 and 0.3% (with one exceptionally high value close to 0.5%). Owing to the local conditions, the differences between CO2 concentrations seem closely to relate to the specific properties of each catchment. Much of the biogenic CO2 present in water that circulates in tundra catchments which have a limestone foundation becomes involved in the dissolution of that limestone. In July 2001, about 40% of the CO2 was used in the dissolution of the carbonate rocks (30.3 kg/km2 month), the “free” CO2 being transported to the sea at Isbjřrnhamna Bay (40.4 kg/km2 month). In contrast, the water flowing through acidic rocks are rich in “free” CO2. The concentrations of dissolved and transported HCO3– ions from the polar catchments are closely correlated with variations in the daily production of biogenic CO2.
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