INFLUENCE OF WEATHER CONDITIONS ON HONEY BEE VISITS (Apis mellifera carnica) DURING SUNFLOWER (Helianthus annuus L.) BLOOMING PERIOD

The objective of the investigation was to determine influence of weather conditions on activity of honey bees during blooming time of six sunflower hybrids. The investigation was carried out in 2002 growing season at Kneževi Vinogradi located in Baranja county, north-eastern edge of Croatia. Honey bees communities were moved to the field trial site inside Langstroth-Rooth\u27s bee-hives. Honey bees visiting sunflower head inflorescence was measured at 100, 200, and 300 meters by counting honey bees four times a day (9.00 am, 11.00 am, 1.00 pm, and 5.00 pm). The influence of weather conditions was analysed by Spearman correlation coefficient. Results of the investigation show significant differences regarding honey-bee visit to the head inflorescences in six hybrids, as well as significant influence of air temperature, humidity, precipitation, minimum and maximum air temperature, as well as wind strength

Microstructural and Electrical Features of Yttrium Stabilised Zirconia with ZnO as Sintering Additive

Adding ZnO reduces sintering temperature of yttria stabilized zirconia. Adding up to 0.5 wt% of ZnO is possible to densify to 8 mol% yttria stabilized zirconia (TZ8Y) to 95% of relative density at 1300 °C, besides, the electrical conductivity increases about 30% at 800 °C when compared to pure TZ8Y with the same relative density and average grain size. These results show that TZ8Y co-doped with ZnO can be a potential electrolyte to solid oxide fuel cells and electrolyzer cells

RNA Interference in Schistosoma mansoni Schistosomula: Selectivity, Sensitivity and Operation for Larger-Scale Screening

RNA interference (RNAi) is a technique to selectively suppress mRNA of individual genes and, consequently, their cognate proteins. RNAi using double-stranded (ds) RNA has been used to interrogate the function of mainly single genes in the flatworm, Schistosoma mansoni, one of a number of schistosome species causing schistosomiasis. In consideration of large-scale screens to identify candidate drug targets, we examined the selectivity and sensitivity (the degree of suppression) of RNAi for 11 genes produced in different tissues of the parasite: the gut, tegument (surface) and otherwise. We used the schistosomulum stage prepared from infective cercariae larvae which are accessible in large numbers and adaptable to automated screening platforms. We found that RNAi suppresses transcripts selectively, however, the sensitivity of suppression varies (40%–>75%). No obvious changes in the parasite occurred post-RNAi, including after targeting the mRNA of genes that had been computationally predicted to be essential for survival. Additionally, we defined operational parameters to facilitate large-scale RNAi, including choice of culture medium, transfection strategy to deliver dsRNA, dose- and time-dependency, and dosing limits. Finally, using fluorescent probes, we show that the developing gut allows rapid entrance of dsRNA into the parasite to initiate RNAi

ANALYSIS OF SUBSIDIES IN CROATIAN BEEKEEPING

Beekeeping in Croatia unlike many other productions was not subsidized until mid nineties. At the time of introduction of first subsidies honey market was very inefficient, and there was hardly any market for other bee products. Several years of implementation enables first analyses. The investigation is based on two complementary data sets, quantitative data on production and subsidies and farmers attitude toward importance of various measures. Croatian beekeepers compared with their colleagues from other transitional countries make business quite well. Major characteristics of Croatian beekeeping are low density (2.7 beehives per km2), relatively high degree of concentration (22.7 beehives per beekeeper) and relatively intensive production (20 kg of honey per beehive and year). Additional importance to the beekeeping gives the export being more than 1/10 of honey production. Introduction of subsidy for honey production in 1998 resulted in 12% increased annual production in 1999. Besides, a number of beehives increased by 11% in 1999, after just one year of beekeeping subsidy. According to HSSC-a in 1997 Croatian beekeepers produced 16000 queens. In 2001 they produced already 38968. Investigation of farmers’ attitude toward influence of various subsidies on their business decisions showed that more than half of beekeepers claimed they were not influenced at all. Subsidies for honey production and queen production had, partially or fully influence on decisions of 25% beekeepers. Subsidy for queen testing had partially or fully influence on decisions of 25% beekeepers. Subsidy for beekeeping was the most important for beekeepers (30.8% of beekeepers were partially or fully influenced), although implementation of this measure was difficult since there is no registry of the beekeepers