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The subject of the research is one of the largest World’s mine tailings disposal sites, i.e. Żelazny Most in the Legnica-Głogów Copper Mining District (south-western Poland), where flotation tailings are poured out after copper ore treatment. The protective hydraulic barrier made of 46 vertical drainage wells was characterized and evaluated in view of reduction of major contaminants (Cl, Na, SO4, Ca) migrating from the facility to its foreground. The efficiency of groundwater protection was determined on the basis of a new approach. In applied method the loads of characteristic and commonly recognizable compounds, i.e. salt (NaCl) and gypsum (CaSO4) were calculated, instead their chemical components. The temporal and spatial variability of captured main contaminants loads as well as its causes are discussed. The paper ends with the results of efficiency analyses of the barrier and with respect to the predicted increase in contaminant concentrations in the pulp poured out to the tailings site.

Lambda-like double-stranded (ds) DNA bacteriophage undergo massive conformational changes in their capsid shell during the packaging of their viral genomes. Capsid shells are complex organizations of hundreds of protein subunits [...]

Visualization of transitional intermediate state is discussed relative to maturation dynamics of a viral capsid. Dynamic aspects of prohead maturation by exploiting the ability of acidic pH to bring on conversion of HK97. Prohead II to Head I in a controlled way. Expansion in vitro by acidic pH has been induced. The changes that resulted were watched using time-resolved X-ray diffraction and cryo-electron microscopy. Three distinct intermediates were seen. They are comarable to transitional states in protein folding. The structures show the molecular events that happen in expansion.

The large size of oligomers produced during HK97 maturation is the reason why this bacteriophage's polypeptides are excluded from polyacrylamide gels after denaturation. Their enlargement is attributed to the intertwining of pentamer and hexamer rings before the covalent cross-linking of the bacteriophage's polypeptides. The adjacent protein rings catenate into a network similar to a chainmail armor. Such a structure is supported by experimental findings on the properties of these bacteriophages.

Gel electrophoresis studies reveal that the complex between the Escherichia coli chaperonin protein, GroEL and the 42 kDa major head protein of the bacteriophage HK97, gp5, is stable. The complexes of GroEL with other peptides are however, in a molten globule-like state. One subunit of gp5 binds to one of the 14 subunits of the GroEL molecule, and a shift occurs in the band position when the charge of the complex is different from the uncomplexed GroEL. Binding of a substrate protein to GroEL is followed by a net binding of solution cations to the complex.

The common laboratory strain of bacteriophage [unkeyable]--[unkeyable] wild type or [unkeyable]PaPa--carries a frameshift mutation relative to Ur-[unkeyable], the original isolate. The Ur-[unkeyable] virions have thin, jointed tail fibers that are absent from [unkeyable] wild type. Two novel proteins of Ur-[unkeyable] constitute the fibers: the product of stf, the gene that is disrupted in [unkeyable] wild type by the frameshift mutation, and the product of gene tfa, a protein that is implicated in facilitating tail fiberassembly. Relative to [unkeyable] wild type, Ur-[unkeyable] has expanded receptor specificity and adsorbs to Escherichia coli cells more rapidly., The tail fibers of the double-stranded DNA bacteriophages are the organelles through which the virus contacts its host in the first steps of the infection process. By forming specific contacts [...]

The present study reports for the first time the occurrence of selected pharmaceuticals and personal care products (PPCPs) in the shallow aquifer underlying the Kraków city. Urban groundwater samples were gathered from 11 wells, which can serve as the emergency water supply wells. Liquid chromatography with tandem mass spectrometry method with the previous pre-concentration of samples using an SPE technique was applied for the determination of the PPCPs selected. There were quantified concentrations of PPCPs from the groups of estrogens (17-α-ethinylestradiol (EE2), 2.6–18.7 ng/L), non-steroidal anti-inflammatory drugs (ketoprofen, 59.5 ng/L in 1 sample), and antimicrobial preservatives used in cosmetic production (methylparaben up to 91.5 ng/L). Triclosan was observed in all analysed water samples in concentrations above the limit of detection. The presence of the PPCPs in the shallow aquifer is an evidence that the sewer network system under the city leaks and then pollutes the urban groundwater. [ABSTRACT FROM AUTHOR]

Various types of landfills pose a direct threat to groundwater. Polluted groundwater is characterized by significantly reduced electrical resistivity. Geophysical methods -- in particular DC-resistivity methods -- are sensitive to this physical parameter. Applying these methods can allow for a spatial assessment of the groundwater quality near the landfills. The key with that approach is to recognize the geoelectrical structure of an area prior to the existence of a landfill. This information will allow for a geoelectrical background, which would most likely be an image of the natural and uncontaminated study area. Subsequent measurements will be more effective due to the possibility of comparing the current state of the area to the original state. This paper presents an example of such a study. Here, the research area of interest was located in the vicinity of an inactive tailings disposal site. In order to assess the pollution of the groundwater, a vertical electrical sounding method was applied. The results of modern measurements were compared with those from the reinterpretation of the data obtained several decades ago. The selected geoelectrical method proved to be effective, allowing for the determination of the range of contaminated groundwater in regions that were not covered by traditional hydrogeological monitoring by a piezometer network. Repetition of vertical electrical sounding in the future will allow for tracking the displacement of pollution within the aquifer. [ABSTRACT FROM AUTHOR]

Our research aimed to evaluate groundwater pollution risk in the study area in southeastern Poland, that is, in an area where the hydrogeological conditions and land use forms are similar to those of European plains. The authors' own qualitative classifications of the potential impact of major forms of land use on groundwater quality and groundwater pollution risk are proposed. The degree of this risk was assessed as the sum of ratings of intrinsic vulnerability of groundwater to pollution assessed with the original DRASTIC method and ratings of the potential impact of land use. The obtained map of groundwater pollution risk showed that 0.3% of the study area was characterized as being at very high risk, 50% as high, 45% as moderate, and 4.7% as low. In a graphical manner, spatial relationships between selected factors affecting the groundwater pollution risk and the assessed degree of risk are presented. The assessment of groundwater pollution risk employing intrinsic vulnerability of groundwater to pollution and potential impact of land use forms, together with the proposed classification of groundwater pollution risk, made it possible to determine areas of high risk of groundwater pollution in the study area in an effective manner. [ABSTRACT FROM AUTHOR]

The double stranded DNA bacteriophage HK97 provides an advantageous system for investigating the structural basis for protein self-assembly and viral capsid maturation. The solution Raman spectra of Prohead I, Prohead II, and Head II particles are structurally interpreted.