The aim of this study was to detect the correlation between the change in the ambient temperature and adaptation of the pronephros – the main haematopoietic organ in fish, which so far has not been subject of research. Compared with other teleosts and their number of blood cells in peripheral blood, tench (Tinca tinca L. 1758) showed the corresponding trend of changes in number of pronephros haematopoietic cells after exposure to increased water temperature. The number of all haematopoietic cell lines was changed during the conditions of thermal stress (P<0.01; P<0.05). The number of erythroblasts was significantly reduced due to shift of haemoglobin curve of dissociation to the right. Leukopoietic cells were increased significantly as a response of pronephros to stress and all endocrine mediators of the stress (cortisol, leukine, etc.). The number of prothrombocytes was slightly decreased due to mobilisation into peripheral blood as in the case of cell precursor of monocytes. Eosinophilic and basophilic granuloblasts were not found in tench pronephros. Correlation (R) between body mass and total length was 0.526. Sex-specific variation of haematopoietic cells number in the same group was not observed (P>0.05), but it was significant between males or females among different groups (P<0.01; P<0.05 respectively).

In this study, concentrations of lead Pb, cadmium Cd and arsenic As were tested in 177 samples of fresh vegetables produced in the area of Zenica. This locality is exposed to the strong influence of high emissions of various pollutants primarily originating from metallurgical and thermal power plants, but also from local heating plants. The accumulation of heavy metals is followed by the types of vegetables: tuber and root, bulb, leaf, fruiting and legume from the group of fruiting vegetables. Preparation of samples was done with microwave digestion. The concentration of the selected metals in solutions after digestion was determined on Induced coupled plasma mass spectrometry (ICP-MS). The percentage participation of contents Pb, Cd and As, either higher or lower than the maximum allowable amount prescribed by the applicable law, was calculated in all 177 samples. The results showed that different groups of vegetables have different ability to adopt and accumulate heavy metals. The largest number of samples containing Pb content above the maximum level (ML) was in the group of leaf vegetables, then in the roots and finally in bulb groups. Cd was at the very limit with the maximum level in the parsley sample, while all other tested samples were in compliance with the applicable regulations. Two of the tested samples of the parsley leaves group had an increased content of As according to the legal regulations.

This paper gives the methodology for driving power calculation of an apron feeder for ore transportation on the example of the apron feeder DO-F in the open pit of the Copper Mine Majdanpek. The analysis was done by calculation for given operating parameters. The apron feeder layout is also presented, as well as the technical characteristics of the driving unit elements.

We investigate global dynamics of the following systems of difference equations , , , where the parameters , , , , , and are positive numbers and the initial conditions and are arbitrary nonnegative numbers. This system is a version of the Leslie-Gower competition model for two species. We show that this system has rich dynamics which depends on the part of parametric space.