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This work provides the first results on activity concentrations, inventories and activity ratios of the artificial and natural fallout (Cs, Pu, Pu, Am, Pb) and lithogenic radionuclides (Ra, Ra, K) in soils and lake sediments of the inland Spitsbergen. The depths of activity peaks of the artificial radionuclides point to accumulation of up to 10 cm thick deposits during last 50 years. The activity ratios of the radionuclides suggest global fallout as their source. Despite low annual precipitation the inventories of fallout radionuclides in sites not affected by the secondary deposition agree with those reported from the more humid areas of Spitsbergen. [ABSTRACT FROM AUTHOR]

Many alkaloids containing a tetrahydro- β-carboline skeleton have well-known therapeutic effects, leading to increased interest in the synthesis of these natural products. Enantiomers of N-Boc-protected 1-hydroxymethyl-1,2,3,4-tetrahydro- β-carboline [(±)- 7], 1-hydroxymethyl-6-methoxy-1,2,3,4-tetrahydro- β-carboline [(±)- 8], and 1-hydroxymethyl-6-fluoro-1,2,3,4-tetrahydro- β-carboline [(±)- 9] were prepared through enzymecatalyzed asymmetric acylation of their primary hydroxyl group. The preliminary experiments were performed in a continuous-flow system, while the preparative-scale resolutions were done as batch reactions. Excellent enantioselectivities ( E>200) were obtained with Candida antarctica lipase B (CAL-B) and acetic anhydride in toluene at 60 °C. The recovered alcohols and the produced esters were obtained with high enantiomeric excess values ( ee≥96 %). The O-acylated enantiomers [( S)- 10-( S)- 12)] were transformed into the corresponding amino alcohols [( S)- 7-( S)- 9)] with methanolysis. Microwave-assisted Boc removals were also performed and resulted in the corresponding compounds ( R)- 4-( R)- 6 and ( S)- 4-( S)- 6 without a drop in the enantiomeric excess values ( ee≥96 %). [ABSTRACT FROM AUTHOR]

Floods in the northern foreland of the Tatra Mountains considerably contribute to the total flood damage in Poland. Therefore, the question whether the magnitude and frequency of floods have changed in this region is of high interest. This study aims at investigating the inter-decadal variability of magnitude, frequency and seasonality of floods since the mid-twentieth century, to better understand regional changes. The analysis was accomplished in a multi-temporal approach whereby trends are fitted to every possible combination of start and end years in a record. Detected trends were explained by estimating correlations between the investigated flood parameters and different large-scale climate indices for the northern hemisphere, and by trends found in intense precipitation indices, number of days with snow cover, cyclonic circulation types, temperature and moisture conditions. Catchment and channel changes that occurred in the region over the past decades were also considered. Results show that rivers in the area exhibit considerable inter-decadal variability of flows. The magnitude and direction of short-term trends are heavily influenced by this inter-decadal variability; however, certain patterns are apparent. More extreme, although perhaps less frequent floods are now likely to occur, with a shift in the seasonality, decreasing flood magnitudes in winter and increasing during autumn and spring. The identification of the factors contributing to the occurrence of flood events and their potential changes is valuable to enhance the flood management in the region and to improve the resilience of the population in this mountainous area. [ABSTRACT FROM AUTHOR]

Poa annua L. (annual bluegrass) is the only non-native flowering plant species that has successfully established a breeding population in the maritime Antarctic and has been shown to maintain a soil seed bank. The characteristic of the spatial structure of the Antarctic population of this species is the formation of distinct dense clumps-tussocks. In the temperate zone the species is only loosely tufted. We focused on the characteristics of seed deposition associated with the tussocks and some aspects of the spatial heterogeneity of the soil seed bank of P. annua in the Antarctic. We wanted to assess the microspatial structure of the soil seed bank of annual bluegrass at Arctowski Station. Therefore we compared the number of seeds deposited underneath and in the vicinity of P. annua clumps. Our results indicate that P. annua in the Antarctic maintains a soil seed bank comparable to species typical for the polar tundra. The microspatial structure of P. annua soil seed bank in the Antarctic is highly associated with the presence of tussocks. Seeds are deposited underneath the tussock rather than in the vicinity of the clump. Our results also indicate that seeds are able to survive the Antarctic winter and readily germinate under optimal conditions. [ABSTRACT FROM AUTHOR]

Six strains of Psychrobacter spp. isolated from guano of little auks collected on Spitsbergen island (Arctic) carried nine plasmids that were fully sequenced. These replicons (ranging in size from 2917 to 14924 bp) contained either repA (ColE2-type) or repB (iteron-type) replication systems of a relatively narrow host range, limited to Psychrobacter spp. All but one of the plasmids carried predicted mobilization for conjugal transfer systems, encoding relaxases of the MOB, MOB or MOB families. The plasmids also contained diverse additional genetic load, including a type II restriction-modification system and a gene encoding a putative subunit C of alkyl hydroperoxide reductase (AhpC)-an antioxidant enzyme and major scavenger of reactive oxygen species. Detailed comparative sequence analyses, extended to all plasmids identified so far in psychrophilic bacteria, distinguished groups of the most ubiquitous replicons, which play a key role in horizontal gene transfer in cold environments. [ABSTRACT FROM AUTHOR]

The study analyses the numbers of days with strong winds in Krakow during the period 2000-2007 using anemometric records and fire department data. Patterns are identified in the seasonal and annual variation of strong winds. Particular attention is devoted to extreme events. Based on measurements, the study finds that strong winds mostly occurred in winter. Fire department call-out data show that repair of damage caused by strong winds and gusts of wind was needed equally as frequently in summertime. Strong winds accompanying summer storms are often of a local nature and are not always recorded by weather stations. Wind damage was mapped using requests for fire department assistance. [ABSTRACT FROM AUTHOR]