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A series of new poly(ethylene oxide) (PEO)-based copolyimides varying in hard segment structure are reported in this work as CO2 selective separation membranes. Their structural diversity was achieved by using different aromatic dianhydrides (4,4′-oxydiphthalic anhydride (ODPA), 4,4’-(hexafluoroisopropylidene)diphthalic anhydride (6FDA)) and diamines (4,4′-oxydianiline (ODA), 4,4′-(4,4′-isopropylidene-diphenyl-1,1′- diyldioxy)dianiline (IPrDA), 2,3,5,6-tetramethyl-1,4-phenylenediamine (4MPD)), while keeping the content of PEO (2000 g/mol) constant (around 50%). To get a better insight into the effects of hard segment structure on gas transport properties, a series of aromatic polyimides with the same chemistry was also studied. Both series of polymers were characterized by 1HNMR, FTIR, WAXD, DSC, TGA, and AFM. Permeabilities for pure He, O2, N2, and CO2 were determined at 6 bar and at 30 °C, and for CO2 for pressures ranging from 1 to 10 bar. The results show that OPDA-ODA-PEO is the most permeable copolyimide, with CO2 permeability of 52 Barrer and CO2/N2 selectivity of 63, in contrast to its fully aromatic analogue, which was the least permeable among polyimides. 6FDA-4MPD-PEO ranks second, with a two times lower CO2 permeability and slightly lower selectivity, although 6FDA-4MPD was over 900 times more permeable than OPDA-ODA. As an explanation, partial filling of hard domain free voids by PEO segments and imperfect phase separation were proposed.

The paper reinterprets the chronology of a weight found in 1961 on Góra (Mount) Chełmska in Koszalin and a symbol placed on one of its poles. The symbol was believed by some scholars to be a runic sign. A re-analysis of the find has revealed that the weight is not an early medieval artefact and the sign is not a rune but a municipal mark.

The results of studies of the vertical gradient of aerosol concentration measurements made during cruises of r/v ‘Oceania’ between 2008 and 2012 are presented. Using the results from those experiments, sea spray emission fluxes were calculated for all particles of sizes in the range from 0.5 μm to 8 μm, as well as for particles of sizes from fifteen channels of 0.5 μm width. The information obtained was further used to calculate the Sea Salt Generation Function (SSGF) for the Baltic Sea depending on the wind speed and the aerosol size distribution.

In the pathogenesis of chronic otitis media (COM), much attention is paid to the molecular mechanisms of local inflammatory reactions in which mast cells (MCs) may be involved due to their role not only in allergic but also inflammatory processes. The aim of this study was to assess the density of mast cells in chronic otitis media in relationship to different clinical courses of COM, bacterial infections and types of disease. The MCs expression was measured immunohistochemically in paraffin-embedded granulation tissue specimens taken during surgery, by staining with a monoclonal antibody against tryptase. The density of tryptase-positive mast cells was lower in tissue samples from the group with a good clinical course than in those from the group with poor healing and recurrence (p = 0.006). There were no differences between the groups of patients with granulomatous and cholesteatomatous chronic otitis media (p = 0.66) or between the groups of patients with and without bacterial infection (p = 0.30), although the density of mast cells was lower for those with Pseudomonas aeruginosa/Proteus sp./ /Staphyloccocus MRSA infection. In conclusion, the expression of mast cells in chronic otitis media granulation tissue was found to differ depending on the clinical course of the disease, but not on bacterial infection or type of COM. This may suggest that mast cells contribute to the maintenance of the inflammatory process, but not to antibacterial defense in chronic otitis media. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 3, pp. 479–485)

A three-dimensional baroclinic sigma-coordinate model was applied to study the circulation and thermohaline variabilityin the coastal zone in the south-eastern Baltic Sea. The model is based on the Princeton Ocean Model code of Blumberg & Mellor(1987), known as POM, and has the horizontal resolution of ~5 km and 24 sigma-levels in the vertical. The hydrodynamic conditions and variability of water and salt exchange between the Gulf of Gdansk and the Baltic Proper, and the renewal of water masses in the Gulf of Gdansk due to atmospheric forcing are analyzed. The numerical simulations were performed with real atmospheric forcings as well as with homogeneous (spatially uniform) wind fields over the whole Baltic Sea. The numerical simulations showed that the atmospheric forcing (winds) can play a significant role in shaping the renewal of bottom saline waters in the Gulf of Gdansk. Two regions of inflow/outflow of saline waters responsible for the salinity regime were located. The overall water exchange between the Gulf and the Baltic Proper as well as the exchange of saline bottom waters appear to be strongly dependent on wind conditions. The net flux of water of salinity >9 PSU is of the order of 48000-100000 m3 s-1. SE, E, S and NE winds were foundto exert the greatest influence on salinity conditions in the Gulf of Gdansk. Estimates of saline (salinity >9 PSU) water residencetime based on the model simulation yielded values from 46 days for SE winds to 153 days for NW winds.

This paper presents the results of an attempt to reproduce, with theaid of a numerical circulation model, the hydrological conditions observedin the coastal area of the southern Baltic in September 1989.A large fall in surface layer seawater temperature was recordedin September 1989 at two coastal stations in the vicinity ofKolobrzeg and Wladyslawowo. This upwelling-like phenomenon was assumed tobe related to the specific anemobaric situation in September 1989,however typical of this phenomenon to occur along the Polish Baltic coast(Malicki & Mietus 1994). A three-dimensional (3-D) sigma-coordinatebaroclinic model of the Baltic Sea, with a horizontal resolution of~5 km and 24 sigma-levels in the vertical, was applied to investigatewater circulation and thermohaline variability. Hindcastnumerical simulation showed that the model provided a good reproductionof the temporal history of the surface seawater temperature and theduration of the upwelling-like fall, but that the model results wereunderestimated. The maxima of this large fall in the surface layertemperature at both coastal stations are closely related to the phase ofchange of the upwelling-favourable wind direction to the opposite one.The results of simulation runs showed details of upwelling developmentdue to wind field fluctuations in time and differences in shaping thetemperature and current patterns in conjunction with the variations intopography and coastline features in some areas along the Polish coast.Two different hydrodynamic regimes of water movements along the coastresulting from topographical features (the Slupsk Bank) can be distinguished.From the model simulation the specific conditions for the occurrence anddevelopment of upwelling at the eastern end of the Polish coast(in the vicinity of Wladyslawowo) can be deduced.

A three-dimensional (3-D) sigma-coordinate baroclinic model is used to investigate water circulation and thermohaline variability in the Baltic Sea. Two versions of the horizontal resolution of ~ 10 km and ~ 5 km with 24 sigma-levels in the vertical are considered. The model is based on the Princeton Ocean Model code of Blumberg & Mellor (1987) and Mellor (1993), known as POM. This paper presents details of simulation strategies and briefly discusses the 'reality' of the results of modelling. The model's capabilities of simulating the characteristic hydrographic features of the Baltic Sea were tested for 3 months (August-October 1995), a simulation related to the period of the PIDCAP'95 experiment (Pilot Study for Intensive Data Collection and Analysis and Precipitation) (Isemer 1996). The model results are compared with the in situ measurements of temperature and salinity at selected hydrographic stations, collected during cruises of r/v 'Oceania' in September and October 1995. Comparison of computed and measured temperature and salinity shows that the model reproduces the vertical structure of seawater temperature and salinity in relatively good accordance with the in situ observations. The differences between the calculated and observed values of temperature and salinity are c. 1-2oC and c. 1-2 PSU, depending on the location of the hydrographic station.

The study focuses on the hydrodynamic processes in the southern Baltic Sea, with special interest in the Stolpe Channel – the only deep water connection between Bornholm Basin to the west and Gdansk and Gotland Basins to the east. The Channel is an area of strong interactions of wind- and density-driven currents that may lead to a complex flow structure. A three-dimensional numerical model was applied to an analysis of processes mentioned above. Three model versions of different spatial resolution (5, 3 and 1Nm) were used to investigate an influence of this parameter on the model results. The simulations were performed for four main wind directions, for a variable in time wind speed. It was shown that water circulation in the southern Baltic is to a high degree dependent on local anemobaric conditions. The results confirm the hypothesis of Krauss and Brugge that the flow in the Channel is opposite to the wind direction. Numerical grid step can have a decisive influence on the modeled circulation patterns, especially when barotropic and baroclinic flow components counteract. In such situations – when the flow is bidirectional and mesoscale eddies are generated – high resolution of the model is particularly important.