Congenital diaphragmatic eventration in two closely related British Shorthair cats

Two closely related British Shorthair cats, which died after surgery performed in the dorsal position, were presented for dissection. In both, a thin, flaccid, enlarged transparent tendinous diaphragmatic portion protruded cranially into the thoracic cavity, forming a cupola in which left, right medial and quadrate hepatic lobes were encased in both cats and the stomach in one cat. Microscopically, no muscle fibres were observed in the membrane, but numerous hepatocytes and bile ducts were incorporated in its central part. The anomaly was diagnosed as a congenital diaphragmatic eventration.     

Distribution of Potato virus Y in potato plant organs, tissues, and cells

The distribution of Potato virus Y (PVY) in the systemically infected potato (Solanum tuberosum) plants of the highly susceptible cultivar Igor was investigated. Virus presence and accumulation was analyzed in different plant organs and tissues using real-time polymerase chain reaction and transmission electron microscopy (TEM) negative staining methods. To get a complete insight into the location of viral RNA within the tissue, in situ hybridization was developed and optimized for the detection of PVY RNA at the cellular level. PVY was shown to accumulate in all studied leaf and stem tissues, in shoot tips, roots, and tubers; however, the level of virus accumulation was specific for each organ or tissue. The highest amounts of viral RNA and viral particles were found in symptomatic leaves and stem. By observing cell ultrastructure with TEM, viral cytoplasmic inclusion bodies were localized in close vicinity to the epidermis and in trichomes. Our results show that viral RNA, viral particles, and cytoplasmic inclusion bodies colocalize within the same type of cells or in close vicinity.     

Influence of land use in small karst watersheds on the chemical status of peloid sediments on the eastern Adriatic coast

Background, Aim and Scope  

Most of the cathment areas supplying water and mineral matter to the Adriatic bays with healing mud/peloids are affected by various degrees of human impact, i.e. activity that is introducing various types of contaminants to environment. The bays represent shallow marine depositional environments where organic-rich sediments accumulate. Investigations for balneological characterization of several localities along the Croatian coast have shown that these organic-rich sediments may be classified as healing mud, i.e. peloids. Healing mud due to its balneologic features is in treatment of various diseases and in improvement of the overall health conditions and general well-being. Various components of mud, particularly trace elements, could be absorbed through dermal contact. Therefore, the study of the abundance of such potentially toxic elements as As, Pb, Hg, Cd, Se, Sb, Cu, Zn in marine sediments used as healing mud is necessary in order to know their mobility and to avoid possible intoxications.     

Organic-geochemical Differentiation of Petroleum-type Pollutants and Study of Their Fate in Danube Alluvial Sediments and Corresponding Water (Pančevo Oil Refinery, Serbia)

A review is given in this paper of the up-to-date results observed in differentiation and transformation studies on petroleum-type pollutants in underground and surface waters. Water and particulate matter derived from the locality of Pan?evo Petroleum Refinery, Serbia (River Danube alluvial formations). It was shown that distributions of n-alkanes, steranes and triterpanes, and δ¹³C_PDB values of n-alkanes may successfully be used for qualitatively differentiating the petroleum-type pollutants from native organic matter in recent sedimentary formations. In underground waters, a petroleum-type pollutant is exposed to microbiological degradation which is manifested through relatively fast degradation of n-alkanes. Following an almost complete degradation of crude oil n-alkanes in underground water, the biosynthesis of novel, even carbon-number C₁₆–C₃₀ n-alkanes may be observed. It is shown that the n-alkane distribution observed in a petroleum-type pollutant may depend on the intensity of its previous interaction with water. The fate of petroleum-type pollutants in environmental waters may be predicted through laboratory simulative microbiological degradation experiments by using microorganism consortiums similar to those observed under relevant natural conditions, as well as on corresponding nutrient base.     

Spatial and vertical distribution of <Superscript>137</Superscript>Cs in soils in the erosive area of southeastern Serbia (Pčinja and South Morava River Basins)

Purpose

The area of southeastern Serbia, the P?inja and South Morava River Basins, is under the influence of very strong erosion, and the aim of this study was to investigate the vertical and spatial distribution of the ¹³⁷Cs in the eroded soils of this area.

Materials and methods

Vertical soil profiles were collected with 5-cm increments from the uppermost layer down to 20, 25, 30, 40, and 50 cm of depth, depending on the thickness of the soil layers, i.e., down to the underlying parent rocks. Measurements of ¹³⁷Cs activity concentration were performed by using the HPGe gamma-ray spectrometer ORTEC-AMETEK (34 % relative efficiency and high resolution 1.65 keV at 1.33 MeV for ⁶⁰Co), from its gamma-ray line at 661.2 keV.

Results and discussion

The mean ¹³⁷Cs activity concentration across all 18 soil profiles (for all soil layers) was found to be 20 Bq kg^?1. In the greatest number of soil profiles, the ¹³⁷Cs activity concentration was generally highest in the first soil layer (0–5 cm) and decreased with soil depth, while in a few soil profiles, the peak of either the ¹³⁷Cs activity concentration occurred in the second soil layer (5–10 cm) or the ¹³⁷Cs activity concentration was almost equal throughout the entire soil profile. The mean ¹³⁷Cs activity concentration in the first soil layer (0–5 cm) was found to be 61 Bq kg^?1, and the high coefficient of variation of 92 % pointed out high spatial variability and large range of the ¹³⁷Cs activity concentrations in the study area.

Conclusions

The obtained results indicate that in the greatest number of soil profiles, ¹³⁷Cs is present in the upper layers, with concentration decreasing with depth, as is typical in uncultivated soil. Its spatial distribution was very uneven among the surface soil layers of the investigated sites. One of the main reasons for such pattern of ¹³⁷Cs in the study area may be soil erosion. Additional investigations which would support this hypothesis are required.

     

Effects of root exudates and humic substances on weathering kinetics

The effect of complex natural organic ligands on the weathering kinetics of aluminum oxide was investigated in laboratory experiments. A peat-derived humic substance and root exudates obtained from ectomycorrhizal (Picea abies — Hebeloma crustuliniforme) and non-mycorrhizal Norway Spruce trees; and γ-Al₂O₃ were used as a model system. The experimental weathering rates are in accordance with a surface-controlled dissolution mechanism. The effect of the humic material on dissolution rates appears to depend on the degree of protonation of the humic (macro)molecules: we observed dissolution-enhancement or -inhibition at pH 3 and 4, respectively. Ectomycorrhizal exudates proved to be effective weathering agents at pH 4, as opposed to humic material and non-mycorrhizal exudates. Our results suggest that (i) the role of humic materials in mineral weathering and podzolization is different from what is commonly thought, and (ii) mineral weathering rates in the rhizosphere may be higher than in the bulk soil.     

Principal component analysis of trace elements in Serbian wheat

Trace elements (Cu, Fe, Pb, Hg, Cd, As, Mn, Zn) were analyzed quantitatively in 14 wheat samples collected from fields in all Serbian growing regions, harvested in 2002. Microelements were determined according to an atomic absorption spectrophotometric method. Principal component analyses (PCA) were performed on data matrices consisting of contents of trace elements in wheats (columns) and all Serbian wheat-growing regions (rows). It was found that four principal components account for 87.2% of the total variance in the data. The plot of component loadings showed significant groupings for concentration of some microelements. The component scores indicated the similarities among the Serbian wheat-growing regions. The loading plot reveals that there is no need to measure all of the variables to achieve the same classification. It is enough to measure one variable per group. Naturally, this conclusion is valid only within the limits of the present study of wheat grain samples from different parts of Serbia.     

Use of the BCR three-step sequential extraction procedure for the study of the partitioning of Cd, Pb and Zn in various soil samples

A slightly modified three-step sequential extraction procedure proposed by the Community Bureau of Reference (BCR) for analysis of sediments was successfully applied to soil samples. Contaminated soil samples from the lead and zinc mining area in the Mezica valley (Slovenia) and natural soils from a non-industrial area were analysed. The total concentrations of Cd, Pb and Zn and their concentrations in fractions after extraction were determined by flame or electrothermal atomic absorption spectrometry (FAAS, ETAAS). Total metal concentrations in natural soils ranged from 0.3 to 2.6 mg kg^-1 for Cd, from 20 to 45 mg kg^-1 for Pb and from 70 to 140 mg kg^-1 for Zn, while these concentrations ranged from 0.5 to 35 mg kg^-1 for Cd, from 200 to 10000 mg kg^-1 for Pb and from 140 to 1500 mg kg^-1 for Zn in soils from contaminated areas. The results of the partitioning study applying the slightly modified BCR three-step extraction procedure indicate that Cd, Pb and Zn in natural soils prevails mostly in sparingly soluble fractions. Cd in natural soils is bound mainly to Fe and Mn oxides and hydroxides, Pb to organic matter, sulphides and silicates, while Zn is predominantly bound to silicates. In contaminated soils, Cd, Pb and Zn are distributed between the easily and sparingly soluble fractions. Due to the high total Cd, Pb and Zn concentrations in contaminated soil close to the smelter, ! and their high proportions in the easily soluble fraction (80% of Cd, 50% of Pb and 70% of Zn), the soil around smelters represents an environmental hazard.     

The Characterization of Heavy Metals in the Grapevine (Vitis vinifera) Cultivar Rkatsiteli and Wild Blackberry (Rubus fruticosus) from East Serbia by ICP-OES and BAFs

Inductively coupled plasma optical emission spectroscopy, in combination with calculation of various biological factors, was used in this study not only for a simple illustration of the present status of some essential and non-essential metals such as copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As), and cadmium (Cd) in the grapevine cultivar Rkatsiteli and wild blackberry from East Serbia but also for the estimation of plant bioaccumulation potentials. Great majority of detected metal concentrations were in normal ranges except in few cases: Zn concentrations were at the level of deficiency in almost all plant parts, and some Cu and As concentrations were at the levels that could be considered phytotoxic. Biological accumulation factors provided very informative data on metal accumulation and translocation in both plants and pointed to low accumulation rates of metals except in the case of Cu, Zn, and As in some wild blackberry tissues.     

Determination of Plant-Available Nutrients in Two Wood Ashes: The Influence of Combustion Conditions

Wood ashes were traditionally used as a fertilizing agent from the very beginning of working land but the fertilizing quality varies according to the combusted biomass and also the industrial burning equipment. The differences between wood ash originated from fluid and classic boiler were investigated by X-ray powder diffraction (XRD), X-ray fluorescence spectrometry (XRF), differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), and Mehlich 3 and deionized water extraction procedures in relation to extraction time. The results, especially of the SEM and chemical extractions, have demonstrated that the type of burning boiler determines the portions of the leachable nutrient elements. The silica and alumina ash content conducted by the elevated temperature transforms the main proportion of calcium and potassium into the insoluble feldspars. Due to this effect only a small amount of nutrients could be released and served as a fertilizing matter.