Temporal variability in 20 chemical elements content of Parasol Mushroom (Macrolepiota procera) collected from two sites over a few years

Mature specimens of Parasol Mushroom were collected annually in the outskirts of the Siemiany (2000–2003) and Rafa (2001–2003) sites in the northern part of Poland to examine temporal variations and similarities in the composition of 20 chemical elements. Analysis was done under the same condition and using well-validated analytical methods. Elements were determined by inductively coupled plasma–atomic emission spectroscopy and cold vapour–atomic absorption spectroscopy (Hg). The ranges of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn concentrations in the caps of fruiting bodies were similar (p > 0.05; Mann-Whitney U test) for both geographically distant sites, and these specimens from Rafa were more contaminated with Pb (p < 0.05; Mann-Whitney U test). The annual collections of caps in the Siemiany site varied in Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, Na, Rb and Sr and contents (0.05 < p < 0.001), while they were similar in Cr, K, Mg, Mn, Ni, P, Pb and Zn (p > 0.05; Mann-Whitney U test). The annual collections of specimens from the Rafa site varied in contents of Ag, Al, Ba, Ca, Fe, Hg, K, Mg, Mn, P, Rb and Zn (p > 0.05), while they were similar in Cd, Co, Cr, Cu, Na, Ni, Pb and Sr (p < 0.05). The results of this study imply that metallic elements content of Parasol Mushroom collected at the same undisrupted sites, and hence keeping the same geochemical condition for mushroom development and fructification (the same stands and probably the same mycelia), can fluctuate over the years or the life-span of mycelium. Hence, when assessing the nutritional value of essential metallic elements and status of non-essential or toxic metallic elements in Parasol's Mushroom caps (and probably also of other mushrooms species) to man, the possible fluctuation in contents over time have to be taken into account.     

QSPR for prediction of subcooled vapor pressures (log PL) of polychlorinated trans-azobenzenes

In this study the values of subcooled vapor pressures (log P_L) were estimated for 209 trans chloroazobenzenes (Ct-ABs) that fill some gaps in analytical and experimental data on these compounds. There are 209 chloro derivatives of trans azobenzenes that are relatively stable and more environmentally relevant than 209 chloro cis congeners. The calculations models were based on the Quantitative Structure-Property Relationship (QSPR) scheme using the semi-empirical method (PM6) in molecular package (MOPAC) software and density functional theory (DFT) method using B3LYP functional and 6-311++G** basis set) in Gaussian 03 software method and the artificial neural networks (ANNs) prediction. The values of log P_L predicted by models used varied between ?3.94 to ?2.66 for Mono-; ?4.85 to ?2.97 for Di-; ?5.18 to ?3.17 for Tri-; ?6.02 to ?3.77 for Tetra-; ?6.64 to ?4.64 for Penta-; ?7.36 to ?4.76 for Hexa-; ?7.54 to ?5.79 for Hepta-; ?7.75 to ?6.64 for Octa-; ?7.89 to ?7.44 for Nona-Ct-Abs; and ?8.09 and ?8.13 for Deca-Ct-AB. Based on these values Ct-ABs can be grouped localized among relatively low (log P_L ?4 to ?2) and low (log P_L < ?4) mobile Persistent Organic Pollutants (POPs). Both the calculation methods employed were characterized by similar prediction ability of subcooled vapor pressure values of Ct-ABs, while those of PM6 are much more efficient due to a cheaper hardware used and around 300-fold less time spent on calculations.     

Mean annual (222)Rn concentration in homes located in different geological regions of Poland: first approach to whole country area

The paper presents the results of year-long measurements of radon (²²²Rn) concentration inside 129 buildings in Poland in relation to the geological conditions of their foundation. The authors took into account the division of the country into tectonic units, as well as the lithology of the rocks forming the bedrock of these buildings. As expected, the highest value of mean annual ²²²Rn concentration (845 Bq/m³) was recorded in a building situated in the area of the Sudetes, while the highest geometric mean (characteristic of the expected log-normal data distribution) was calculated based on measurements from buildings located within the East-European craton, in the area of Mazury-Podlasie monocline, where it reached 231 Bq/m³. Such results reflect geological conditions - the occurrence of crystalline rocks (especially U- and Ra-enriched granites and orthogneisses) on the surface in the Sudetes, and of young post-glacial sediments containing fragments of Scandinavian crystalline rocks, also enriched with U and Ra, in the area of Mazury-Podlasie monocline. However, the least expected result of the investigations was finding out that, contrary to the hitherto widespread belief, none of the major tectonic units of Poland can be excluded from the list of those containing buildings with mean annual ²²²Rn concentration exceeding 200 Bq/m³. The mean annual concentration of radon for all the buildings were much higher than the mean concentration value (49.1 Bq/m³) of indoor radon in Poland quoted so far. These results cast a completely new light on the necessity to perform measurements of radon concentration in residential buildings in Poland, no more with reference to small areas with outcrops of crystalline rocks (especially the Sudetes, being the Polish fragment of the European Variscan belt), but for all the major tectonic units within Poland.     

Profile of trace elements in Parasol Mushroom (Macrolepiota procera) from Tucholskie Forest

The aim of this study was to determine 19 elements contents and bioconcentration potential in fruiting bodies of Parasol Mushroom (Macrolepiota procera) collected from the Tucholskie Forest complex in Poland. Also discussed were Cd, Pb and Hg contents of edible caps in relation to the current regulatory standards. K, P and Mg were particularly abundant in caps and stipes, median values were 38-49, 13, and 1.6-1.6 mg/g dry weight, and followed by Ca, Na and Rb at 110-540, 44-240 and 20-50 μg/g dw, respectively. Concentrations of Al, Fe, Zn, Cu and Mn were from less than 50 to 180 μg/g dw, while concentrations of other elements were ～l.0?μg/g dw or less. Cu, K, Ag, Cd, Na, Rb, Zn and Hg were bioconcentrated (BCF >1), while Al, Ba, Fe, Mn, Co, Sr, Pb and Cr were not bioaccumulated (BCF <1). Cd and Pb content of Parasol Mushroom's edible caps collected from some sites in the Tucholskie Forest exceed the maximum levels set in the EU for cultivated mushrooms.     

Influence of solar UV radiation on the nitrogen metabolism in needles of Scots pine (Pinus sylvestris L.)

Needles of 20-year-old Scots pine (Pinus sylvestris L.) saplings were studied in an ultraviolet (UV) exclusion field experiment (from 2000 to 2002) in northern Finland (67 °N). The chambers held filters that excluded both UV-B and UV-A, excluded UV-B only, transmitted all UV (control), or lacked filters (ambient). UV-B/UV-A exclusion decreased nitrate reductase (NR) activity of 1-year-old needles of Scots pines compared to the controls. The proportion of free amino acids varied in the range 1.08-1.94% of total proteins, and was significantly higher in needles of saplings grown under UV-B/UV-A exclusion compared to the controls or UV-B exclusion. NR activity correlated with air temperature, indicating a “chamber effect”. The study showed that both UV irradiance and increasing temperature are significant modulators of nitrogen (N) metabolism in Scots pine needles.     

Microbially mediated cadmium sorption/desorption processes in soil amended with sewage sludge

A multi-compartment system was used to study the importance of microorganisms for Cd desorption from soil amended with sewage sludge and simultaneous resorption of the mobilized metal by soil constituents. Using this system made it possible to study the participation of microorganisms (Arthrobacter, Trichoderma), montmorillonite, humic acids, and iron oxides in resorption of the released Cd. A filter-sterilized water extract of root-free soil of pH 6.7 (RF) or RF supplemented with glucose (RFG) were used to mobilize Cd from soil at 14 degrees C in 48 h. Cadmium found in those extracts after 48-h incubation was recognized as bioavailable. Changes in pH values and enrichment of soil extracts with organic acids and siderophores resulted from microbial growth. RFG with lower pH and a higher content of ligands mobilized, on average, 40% of Cd introduced with sewage sludge amended soil, whereas RF mobilized only 20% of it. Sequential extractions of Cd at time 0 and Cd remaining in soil showed that RFG had mobilized Cd mostly from the fraction bound with Fe and Mn oxides. Microbial biomass accounted for only up to 3.4% (w/w) of the soil constituents used in the experiments but resorbed 25% of mobilized Cd. The chemical composition of mobilizing soil extracts and the solid-to-mobilizing-extracts volume ratio had a significant effect on the amount of bioavailable Cd. The results of the study suggest that microbial metabolites were involved in Cd mobilization, while the biomass of microorganisms was involved in Cd resorption as a biosorbent.     

Variations in the Fluoride Level in Precipitation in a Region of Human Impact

The research concerns the Wielkopolski National Park (West Poland), which suffered a huge human impact in the 1970s and 1980s owing to the nearby location of an industrial plant. Since then, fundamental technological changes that it introduced into its production of phosphate fertilizers have radically reduced the amount of pollution emitted. A three-year study (2002–2004) of fluorides in precipitation in open terrain and under tree crowns showed their concentrations to range from levels below the detection limit (0.003 mg/l) to 0.560 mg/l. Those registered under tree crowns were several times higher and indicated substantial dry deposition of fluorides on the trees. The highest values were recorded in 2003, with 43% of samples ranging from 0.01 to 0.05 mg/l, and with 51% of throughfall ranging from 0.10 to 0.50 mg/l. A strong connection was shown to exist between fluoride and sulphate concentrations in the precipitation. An analysis was made of the available data on F concentrations in the air and the dust levels around the factory, but these figures did not show an unequivocal effect on F concentrations in precipitation. A great similarity was found to occur between the fluoride content in rainwater in the Wielkopolski National Park and in the centre of the nearby Poznań metropolitan area, which indicates that there are also other F sources besides the local factory.     

Synergy between visual and auditory signals and its influence on the follow-up regulation quality.

The study aimed at verifying a hypothesis that supporting a visual signal of regulation deviation with an auditory one could improve the quality of regulation; the operator would have better information on machine operation. A special simulator was applied to follow-up tracking with a manual lever which controlled vertical movements of a cursor on a monitor screen. Simultaneously with visual information on screen, the operator was provided with an auditory deviation signal of pre-determined characteristics. 33 young males underwent the test. It was found that supporting a visual signal with an auditory one resulted in an improvement in the regulation quality by 5-6%, which proved synergy between those signals. The results may be used in designing tele- and servo-mechanisms, especially for remote control machinery, e.g., inspection robots or micromanipulators controlled by operators in a follow-up system.     

Mercury in wild mushrooms and underlying soil substrate from Koszalin, North-central Poland

Concentrations of total mercury were determined by cold-vapour atomic absorption spectroscopy (CV-AAS) in 221 caps and 221 stalks of 15 species of wild growing higher fungi/mushrooms and 221 samples of corresponding soil substrate collected in 1997-98 in Manowo County, near the city of Koszalin in North-central Poland. Mean mercury concentrations in caps and stalks of the mushroom species examined and soils varied between 30+/-31 and 920+/-280, 17+/-11 and 560+/-220, and 10+/-9 and 170+/-110 ng/g dry matter, respectively. Cap to stalk mercury concentration quotients were from 1.0+/-0.4 in poison pax (Paxillus involutus) to 2.8+/-0.7 in slippery jack (Suillus luteus). Brown cort (Cortinarius malicorius), fly agaric (Amanita muscaria), orange-brown ringless amanita (A. fulva), red-aspen bolete (Leccinum rufum) and mutagen milk cap (Lactarius necator) contained the highest concentrations of mercury both in caps and stalks, and mean concentrations varied between 600+/-750 and 920+/-280 and 370+/-470 and 560+/-220 ng/g dry matter, respectively. An estimate of daily intake of mercury from mushroom consumption indicated that the flesh of edible species of mushrooms may not pose hazards to human health even at a maximum consumption rate of 28 g/day. However, it should be noted that mercury intake from other foods will augment the daily intake rates. Species such as the sickener (Russula emetica), Geranium-scented russula (R. fellea) and poison pax (P. involutus) did not concentrate mercury as evidenced from the bioconcentration factors (BCFs: concentrations in mushroom/concentration in soil substrate), which were less than 1. Similarly, red-hot milk cap (L. rufus), rickstone funnel cap (Clitocybe geotropa) and European cow bolete (S. bovinus) were observed to be weak accumulators of mercury. Fly agaric (A. muscaria) accumulated great concentrations of mercury with BCFs reaching 73+/-42 and 38+/-22 in caps and stalks, respectively. Mercury BCFs of between 4.0+/-2.3 and 23+/-25 (caps) and 2.6+/-1.9 and 14+/-12 (stalks) were noted for the other mushroom species. Relatively great concentrations of mercury in fly agaric (A. muscaria) were due to preferential uptake of this element by this species.     

470-Million-year-old black corals from China

Phosphatic (possibly secondarily phosphatised) remains of antipatharian coralla, previously unknown in the fossil record, occur abundantly in the early Ordovician Fenxiang Formation in the Hubei Province, southern China. Probably two species (and genera) are represented, which differ in spinosity of branches. The more spinose one, Sinopathes reptans, has its lateral spines bearing regular, longitudinally arranged costellae. The early Floian geological age of this finding, about 470?Ma, supports predictions on the timing of anthozoan phylogeny derived from the molecular phylogenetic evidence. Black corals (Antipatharia) are basal to the scleractinians in the Hexacorallia clade, being more derived than sea anemones and the Zoantharia. Based on calibration of the molecular clock with Mesozoic data, the first split of lineages within the scleractinian hexacorals was proposed to take place approximately 425 million years ago. This implies that the origin of Antipatharia should precede this date. They have not been known in the fossil record because of unmineralised skeleton composed primarily of laminar chitin complexed with a protein. Unlike all recent species, the encrusting basal part of the colony dominated in the Ordovician ones and only occasionally erect branches developed, rather chaotically ramified. This presumably plesiomorphic trait seems consistent with ancient geological age and suggests that some problematic fossils from the Late Cambrian may be their, even less-derived, relatives.