We have examined the correlation between heat tolerance and small heat shock protein (sHSP) expression under heat stress conditions in potato (Solanum tuberosum l.). The relative heat tolerance of nine potato cultivars grown under greenhouse conditions was determined using the electrolyte leakage assay (el A), a standard quantitative assay for heat tolerance. Three cultivars differing in heat tolerance were selected and designated as heat-tolerant (' laura'), moderately sensitive (' liseta') and heat-sensitive ('Agria') genotypes. The expression of cytosolic HSP18 and chloroplast HSP21 was analyzed at the protein level in the leaves of selected cultivars, both ex vitro- and in vitro-grown , after heat stress or control treatment. Immunoblot analysis revealed heat-induced HSP18 and HSP21 expression in all examined genotypes. A similar pattern of examined sHSP expression was observed ex vitro and in vitro: heat-tolerant ' laura' accumulated higher levels of both HSP18 and HSP21 compared to heat-sensitive ' liseta' and ' Agria'. Our results indicate that elA combined with im- munoblot analysis of sHSP accumulation under HS conditions, might be considered as a reliable procedure in screening potato genotypes for heat tolerance. to our knowledge, this is the first study where sHSP expression between ex vitro- and in vitro-grown potato plants was compared.

In order to obtain multifunctional materials with good biocompatibility and antimicrobial effect, hydroxyapatite (HAp) doped with Zn2+ was synthesized by hydrothermal method. Powders with different content of zinc ions were synthesized and compared with undoped HAp to investigation of Zn2+ ion influence on the antimicrobial activity of HAp. Analyses of undoped and Zn2+-doped powders before and after thermal treatment at 1200oC were performed by SEM and XRD. Antimicrobial effects of powders were examined in relation to Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans in liquid medium. The results showed that the obtained powders have good antimicrobial activity, but higher antimicrobial activities of powders doped with Zn2+ were observed after annealing at 1200°C. For powders annealed at 1200°C in vitro biocompatibility tests MTT and DET with MRC-5 fibroblast cells in liquid medium were carried out. Based on MTT and DET tests it was shown that powders do not have a significant cytotoxic effect, which was confirmed by SEM analysis of MRC-5 fibroblast cells after theirs in vitro contact with powders. [Projekat Ministarstva nauke Republike Srbije, br. III 45019 and FP7-REGPOT-2009-1 NANOTECH FTM]

This paper deals with the production of limestone at the stable plant separation of the open pit 'Duboki potok-Bijela rijeka'. Besides that, the effects of different levels of production and material flows were researched. Research was carried out in a fixed plant separation of the open pit limestone 'Duboki potok-Bijela rijeka' in Duboki Potok. Positions of research were on the secondary part of separation (impact crusher, routers materials, funnels, rubber conveyors, vibrating screens, etc). In the course of using different methods of measuring material flow, calculating capacity conveyors, laboratory methods where used in measuring size and distribution obtained material, and particle shape. The research results were reported in: - particle size distribution diagrams of the obtained aggregate stone with the best bands of particle size distribution - defining the functional dependence of impact crusher gap size distribution and structure of the obtained materials.

The present paper analyzes the operation of the plant for washing stone aggregate 0/2 mm. Researches were conducted on a semi fixed plant for washing aggregates at the open pit 'Drenik' in Srebrenik. Positions of exploration works were on dispenser entrance points, hydrocyclones, distribution system for water supply rubber belt conveyors, etc.). The methods for measuring material flow, calculation the capacity of conveyors, laboratory methods for grain-size distribution of the obtained material were used in this work. The research results are present in the form of tabular data and dependence diagrams of filler content (fractions of technical stone aggregate, granulation -0.063 mm) on capacity of dosed material.