The influence of maize residues on the mobility and binding of benazolin: investigating physically extracted soil fractions

The amount of non-extractable residues and the distribution of benazolin and its metabolites were evaluated three months after herbicide application (14C-labelled) in physically extracted soil fractions of topsoil layers of undisturbed soil columns with and without incorporated maize straw (14C-labelled). In addition, a variety of wet-chemical and spectroscopic methods were used to characterise the structure of organic carbon within the different soil fractions. The addition of crop residues increased the amount of dissolved organic carbon, enhanced the aromaticity of the organic carbon structure and enforced the aggregation of organomineral complexes. After incorporation of crop residues, an increase in the formation of metabolic compounds of benazolin and of non-extractable residues was detected. These results indicate that the addition of crop residues leads to a decrease in mobility and bioaccessibility of benazolin and its metabolites.     

Bendiocarbamate induced structural alterations in rabbit thymus after experimental peroral administration

In this study histological structure of rabbit thymus after bendiocarbamate (2,3-isopropyledene-dioxyphenyl methylcarbamate) administration was studied. Bendiocarbamate was perorally administered for 90 days. At Day 3, 10, 20, 30, 60, 90 morphometric analysis was realized. Quantitative evaluation showed that in the control group thymus cortex forms 57.94 +/- 7.10% and medulla 35.94+/- 7.38%. In almost all experimental groups significantly higher relative volume of cortex and lower relative volume of medulla was detected. Detail morphometric analysis found that the number of thymocytes per constant area and the diameter of tymocytes was decresed after bendiocarbamate administration. The number and diameter of reticular cells was not affected. Results of this study suggest negative effect of bendiocarbamate on the formation of thymus structures.     

Concentration of heavy metals in various children's herbal tea types and their correlations

This investigation was undertaken to determine the concentrations of cadmium, lead, mercury, zinc, copper and magnesium in six tea types used as children's tea. Six types of tea of different herbal composition used for children's consumption (T1, T2, T3, T4, T5 and T6) were analyzed in three subsequent collections. The analysis of cadmium showed that the concentration was very similar in all types of children's tea, ranging from 0.233 to 0.369 mg/kg. Lead concentrations were in the range of 0.340–1.564 mg/kg without any significant differences. The analysis of mercury detected very low concentration of this metal in all samples (0.002–0.004 mg/kg). In zinc, the values ranged from 36.633 to 71.711 mg/kg, with significant differences (p < 0.001) according to tea type. Copper concentration was 10.089–30.178 mg/kg with the highest value in T4. The concentration of magnesium was significantly higher in tea T1 and T2 (102.311 and 129.422 mg/kg) in comparison with other tea types where the level was 19.811–37.411 mg/kg. The maximum tolerable limit determined by Codex Alimentarius was not exceeded in any sample. In general, correlation analysis detected high positive correlation between cadmium and lead (r = 0.89), cadmium and mercury (r = 0.92) and between lead and mercury (r = 0.77).     

Of Domestic and Wild Guinea Pigs: Studies in Sociophysiology, Domestication, and Social Evolution

Cavia aperea   and Galea musteloides) and domestic (Cavia aperea f. porcellus) guinea pigs, which summarizes general rules for many group-living mammals. It is shown that social interactions have consequences not only for the individuals' reproductive success but also for their degrees of stress and welfare. The way in which individuals interact is controlled not only by the present environment but also by the previous social experiences which they have gathered during their behavioral development. Furthermore, the study of ontogeny does not begin at birth, because prenatal social factors acting on pregnant females can also affect the way in which the offspring will interact when adult. In addition, to understand the genesis of interactions between domesticated animals implies knowledge of the behavioral and physiological changes which occurred during the process of domestication. Finally, understanding the social interactions among individuals of the wild ancestor of the domesticated form requires knowledge of how their behavior patterns were brought about by natural selection during the process of social evolution.     

Untersuchungen zur Nachhaltigkeit der Sanierung von Tributylzinnkontaminiertem Hafensediment durch Landablagerung

To allow ships to pass, most harbours have to be liberated from sedimented material. These sediments often contain high concentrations of tributyltin (TBT), which is used as a biocide in antifouling paints. Thus, the problem of a disposal which is acceptable with respect to a minimum risk for humans and the environment arises. The aim of our project was to assess land deposition as an alternative in dealing with TBT-contaminated harbour sediments. Therefore, we followed the biological degradation of TBT under aerobic and anaerobic conditions at different temperatures using defined laboratory experiments, and got important information about the land deposition, performing field measurements including biomonitoring. The biological degradation of TBT is faster under aerobic conditions and with increasing temperature. The half-lives found show the dependency of the degradation rates on the temperature between 5–55°C. The degradation rate determined for water under the same conditions (just biological degradation, without photolysis) is almost 4 times higher than in sediment. The field studies showed degradation rates of a maximum of 10–15% per year in untreated sediment and 30% per year in restacked sediments. We did not observe any interference of released TBT with ground water or surrounding areas. The TBT uptake in plants was low. Based on our results a multidimensional risk evaluation was performed, concerning the TBT and its degradation products dibutyltin (DBT) and monobutylin (MBT) released from the deposition areas. The land deposition appears to be a sustainable solution for dealing with TBT-contaminated harbour sediments.