Gill Reaction to Pollutants from the Tamiš River in Three Freshwater Fish Species,Esox lucius L. 1758, Sander lucioperca (L. 1758) and Silurus glanis L. 1758: A Comparative Study

The study evaluated the effects of waterborne pollutants from the Tami? River on gill histology and possible differences in gill reaction patterns between three freshwater fish species, pike Esox lucius L. 1758, pike‐perch Sander lucioperca (L. 1758) and wels catfish Silurus glanis L. 1758 from the Tami? River. Gills from analysed fish species showed moderate to intense histopathological alterations. The most frequent progressive alteration was hyperplasia of epithelium, whereas the most frequent regressive alteration was epithelial lifting. Circulatory disturbances were most often manifested in the form of hyperaemia. During comparative analysis, differences in gill indices, reaction and alteration indices, as well as in gill and filament prevalence between analysed species, were observed. Although all analysed fish species did show both progressive and regressive alterations, there was a significant difference in the level of expression of these reaction patterns. Gill index obtained for pike clearly stands out as the lowest. Wels catfish showed the highest progressive reaction index, significantly higher in comparison with the other two species (P < 0.05), while pike‐perch showed the highest regressive reaction index, also significantly higher in comparison with the other species (P < 0.001). These results may implicate species‐specific gill reactions and thus present a useful tool for better understanding toxic mechanisms of various pollutants.     

Chigger mites (Acari: Trombiculidae) from wild birds in Costa Rica, with a description of three new species

Three new species of chigger mites, Eutrombicula costaricensis sp. n., Eutrombicula passerinoruni sp. n., and Eutrombicula hectochaeta sp. n. are described from wild birds from Costa Rica. Two species, Eutrombicula pacae (Floch et Fauran, 1957) and Parasecia findata (Brennan, 1969), are recorded for the first time in Costa Rica and on new host species. Data on the distribution of Blankaartia sinnamaryi (Floch et Fauran, 1956) in Costa Rica are also reported.     

Evidence for genetic diversity of Toxoplasma gondii in selected intermediate hosts in Serbia

To contribute to the insight into the worldwide population structure of Toxoplasma gondii, we genetically characterized a total of eight strains isolated from intermediate hosts including humans, sheep and pigeons in Serbia. Although parasite DNA was detected in 28.2% (60/213) of the human samples from 162 patients serologically suspected of active toxoplasmosis, as well as in 5/7 seropositive pigeons and in 2/12 seropositive sheep examined, multilocus PCR-RFLP genotyping, using SAG1, 5′SAG2, 3′SAG2, GRA6, 5′GRA7 and 3′GRA7 as markers, was successful in only four human isolates (of which one was isolated from both the bronchoalveolar lavage fluid and blood samples of a single patient), one sheep and three pigeons. Of the eight isolates, five were type II (62.5%), one was type III, one was atypical, and one had a type I allele at GRA6 as the single locus genotyped. Although type II, as elsewhere in Europe, predominated, these results may suggest a higher genetic diversity of T. gondii in Serbia, reflecting local environmental contamination and also the geographical position of the country in South-East Europe.     

Landscape effect for the Cervidaes Cervidae in human-dominated fragmented forests

We analyse the relationships between the main Cervidae [moose (Alces alces), red deer (Cervus elaphus) and roe deer (Capreolus capreolus)] species and a complex of environmental factors in an extensive fragmented landscape of Central Lithuania. The highest determining positive influence on moose density was the proportions of wet forest sites. In forest complexes with fewer proportions of wet sites, the most important factor was the total forest area. The proportion of shrub cover, upland and dense undergrowth area, and road density also has significant effect on moose density. The total area of forest complexes has the highest determining positive influence on red deer density. The highest density of red deer was calculated in large forest complexes (>2,745 ha) with a <17.6 % proportion of pine and <36.5 % of deciduous forests. Other significant factors were core area, road density and urbanization level. Forest edge density has the highest influence on the roe deer populations. The highest density of roe deer was recorded on forest areas with >51 m ha^?1 of edges in wet forest (>25.4 %) dominating areas. The proportion of deciduous, coniferous mixed and pine forest, also shrub and density of edges also had significant effect.     

Spectral sensitivity in the photodegradation of fir wood (Abies alba Mill.) surfaces: colour changes in natural weathering

Activation spectra of wood under natural irradiation were investigated in detail in this work. The main purpose was to study colour changes on the wood surface over time and into the depth during natural light exposure and thus to further contribute to the optimization of surface-protecting treatments. In a natural weathering test, three 80-μm-thick strips of fir wood forming the surface layer of a wood composite were exposed to light under a series of glass cut-off filters. Samples were withdrawn at intervals and tested for colour changes. Identification of the most detrimental wavebands of light causing photodegradation was performed based on recorded colour changes. With chronological development of exposure, the colour changes shifted ever deeper into the surface and further into the visible region of the spectrum. A relatively narrow waveband from 360 to 435 nm was identified in the activation spectra to be the most active band, causing the greatest proportion of recorded colour changes. However, also visible light of wavelengths up to 515 nm significantly contributed to colour changes of the surface layers.     

N. femoralis, N. obturatorius and N. ischiadicus: deviation in creation in the dogs

Two hundred and twelve dog cadavers belonging to different breeds were examined, to investigate the formation of the femoral, obturator and the sciatic nerve. Besides the commonly described formation patterns of the mentioned nerves, some variations were also found. These variations were not gender-related, but on the other hand we discovered a certain correlation between the variations appearing in the formation of the femoral, obturator and the sciatic nerve. In 74.05% of cases, the femoral nerve was formed from ventral branches of the 4th, 5th and 6th lumbar nerve, and 16.98% of the dogs had the nerve formed from ventral branches of the 3rd, 4th and 5th lumbar nerve. Many dogs (i.e. 2.30%) had the femoral nerve formed from the ventral branches of the 5th, 6th and 7th, the 3rd, 4th, 5th and 6th or the 4th, 5th, 6th and 7th lumbar nerve, respectively. In 1.88% of dogs in particular, the femoral nerve was formed from ventral rami of the 4th and 5th lumbar nerve. In 66.98% of the examined dogs, the obturator nerve was formed from the ventral branches of the 4th, 5th and 6th lumbar nerve, followed by 16.59% of the dogs with the obturator nerve formed from the ventral rami of the 4th and 5th lumbar nerve and 9.43% of dogs in which the nerve was formed from the ventral branches of the 5th and 6th lumbar nerve. In 4.71% of dogs, the obturator nerve was formed from the ventral rami of the 4th, 5th, 6th and 7th lumbar nerve, while only 2.30% of the examined dogs had the same nerve formed from the ventral branches of the 5th, 6th and 7th lumbar nerve. The sciatic nerve was formed from ventral branches of the 6th and 7th lumbar nerve and the 1st sacral nerve in 86.79% of the dogs. In 5.18% of cases, the same nerve was formed from a junction of the ventral branches of the 7th lumbar and the 1st and 2nd sacral nerve, and, in the same percentage of cases, it was formed from a junction of ventral branches of the 6th and 7th lumbar nerve and the 1st and 2nd sacral nerve. In 2.83% of the dogs, it was formed from a junction of the ventral branches of the 6th and 7th lumbar and the 1st sacral nerve. The correlation of variations established in the formation of the femoral, obturator and the sciatic nerve was not statistically significant.     

Assessment of the retardation of selected herbicides onto Danube sediment based on small column tests

Journal of Soils and Sediments - This study utilizes column tests to investigate the retardation of certain herbicides with different hydrophobicities (atrazine, alachlor and trifluralin) during...     

Impact of controlled redox conditions on nickel in a serpentine soil

Purpose  

Serpentine soils exist in many regions around the world; they are naturally enriched with nickel (Ni). An adequate understanding of soil processes determining Ni solubility is a special need particularly since less research has been addressed to Ni behavior under dynamic and controlled redox conditions. Our aim was (1) to characterize the properties of a serpentine soil and (2) to determine the impact of predefined redox windows on the mobility and dynamics of Ni in a serpentine soil.     

Changes in the content of free sulphydryl groups during postharvest wheat and flour maturation and their influence on technological quality

The main aim of this study was to determine the changes in free sulphydryl content during postharvest wheat and flour maturation. The content of free sulphydryl groups was determined from wet gluten over 50 days of wheat postharvest maturation and over 14 days of flour maturation by varying incubation temperatures (30 and 37 °C) and incubation times (0, 45, 90 and 135 min). The amount of free sulphydryl groups increased during postharvest wheat and flour maturation as well as with the increase in temperature and gluten incubation time. The additional aim of this study was to find the interrelation between the content of free sulphydryl groups and selected parameters of technological quality by means of Principal Component Analysis. During wheat/flour maturation, the strengthening of protein structure was observed manifested by the increase in gluten index and Mixolab protein network weakening (C2), and changes in dough resistance as well. The incubation temperature of 37 °C affected the weakening of protein structure manifested by the decrease in gluten index and resistance, and increase in extensibility. Strong differentiation of examined varieties in terms of selected quality indicators was observed upon pre-defined maturation period, probably due to the expression of their intrinsic properties.