Interaction between Fe-cyanide complex and humic acids

The fate of cyanides in soil is strongly influenced by the formation of Fe cyanides, which can interact with organic and inorganic colloids and precipitate as stable compounds. Scarce information is available on the capacity of humic acids to interact with cyano-complexes and thus affect the leaching and prevent the risk of contamination of watertable. Here we show that interaction between humic acids (HAs) and ferricyanide complex led to a formation of ferricyanide-humo micelles, and that the interaction did not imply changes in the original structure of ferricyanide complex.     

What drives visitors to tourist sites to choose “green” accommodation facilities?

Environment, Development and Sustainability - Our aim is to determine the factors influencing a visitor’s decision to stay in a green accommodation facility. Visitors from six tourist sites...     

Chromium in soil layers and plants on closed landfill site after landfill leachate application

Landfill leachate (LL) usually contains low concentrations of heavy metals due to the anaerobic conditions in the methanogenic landfill body after degradation of easily degradable organic matter and the neutral pH of LL, which prevents mobilization and leaching of metals. Low average concentrations of metals were also confirmed in our extensive study on the rehabilitation of an old landfill site with vegetative landfill cover and LL recirculation after its treatment in constructed wetland. The only exception was chromium (Cr). Its concentrations in LL ranged between 0.10 and 2.75 mg/L, and were higher than the concentrations usually found in the literature. The objectives of the study were: (1) to understand why Cr is high in LL and (2) to understand the fate and transport of Cr in soil and vegetation of landfill cover due to known Cr toxicity to plants. The total concentration of Cr in LL, total and exchangeable concentrations of Cr in landfill soil cover and Cr content in the plant material were extensively monitored from May 2004 to September 2006. By obtained data on Cr concentration in different landfill constituents, supported with the data on the amount of loaded leachate, amount of precipitation and potential evapotranspiration (ETP) during the performance of the research, a detailed picture of time distribution and co-dependency of Cr is provided in this research. A highly positive correlation was found between concentrations of Cr and dissolved organic carbon (r = 0.875) in LL, which indicates the co-transport of Cr and dissolved organic carbon through the system. Monitoring results showed that the substrate used in the experiment did not contribute to Cr accumulation in the landfill soil cover, resulting in percolation of a high proportion of Cr back into the waste layers and its circulation in the system. No negative effects on plant growth appeared during the monitoring period. Due to low uptake of Cr by plants (0.10–0.15 mg/kg in leaves and 0.05–0.07 mg/kg in stems of Salix purpurea), the estimated Cr offtake from LL by plants represented only a small proportion of the LL Cr mass load during the observation period, resulting in no dispersion of Cr into the environment through leaf drop.     

Influence of parasitism on the use of small terrestrial rodents in environmental pollution monitoring

Bioaccumulation of cadmium, chromium, copper, manganese, nickel, lead and zinc in small terrestrial rodents – voles and their cestode parasite Paranoplocephala dentata was studied. Contents of Pb, Mn, Ni and Zn in the parasite were found to be higher than in the kidney and liver of the parasitized animals. Lead level in the cestode was 37 fold higher than in the liver of the infected rodents. Bioaccumulation factors of zinc, nickel and manganese in the cestode are mostly in the range from 2 to 4.5. Considering the different contents of manganese and zinc in livers of non-parasitized and parasitized rodents, kidney tissue was found to be more reliable than liver as an indicator of environmental pollution by manganese and zinc; the kidneys of parasitized animals showed no significant change in the concentrations of those elements that are accumulated in the cestode.     

Photochemical pollution indicators—an analysis of 12 European monitoring stations

Indicators were devised to classify air pollution monitoring sites according to the type of expected photochemical pollution. The indicators are based on measured ozone volume fractions, the most frequently monitored component of photochemical pollution, and in particular on two contributions: one due to the ratio of daily maximum-to-minimum ozone volume fractions and the other to observed peak values. The two contributions regarded as independent are logically connected by “and” and therefore mathematically combined by multiplication. The criterion of classification is mainly described by the mentioned ratio and incidences of ozone volume fractions exceeding the limit of 80 ppb. Twelve monitoring stations within the European network (Cooperative programme for monitoring and evaluation of long-range transmission of air pollutants in Europe, EMEP) were classified according to this indicator predicting what ozone levels can be expected at the particular sites during the growth season (April through September) into three groups: clean, medium, and polluted, based on the data for the 7 years (1997 to 2003).     

Compassion fatigue and compassion satisfaction among family physicians in the Republic of Srpska,Bosnia and Herzegovina

Aims. The aim of this study was to examine self-perceived compassion fatigue and compassion satisfaction among family physicians in Bosnia and Herzegovina and describe potential contributing factors. Methods. The cross-sectional study enrolled 120 family physicians. Professional quality of life compassion satisfaction and fatigue version 5 (ProQOL5) was used to assess compassion satisfaction and two components of compassion fatigue, secondary traumatic stress and burnout. The symptoms of chronic fatigue were evaluated using the Chalder fatigue scale. Results. The majority of family physicians had moderate levels of compassion satisfaction (70%), burnout (75%) and secondary traumatic stress (55.8%). Family physicians with higher levels of secondary traumatic stress reported chronic fatigue (p?=?0.001), longer length of service (p?=?0.024) and residency training (p?=?0.041). Chronic fatigue (p?=?0.001), living in a rural environment (p?=?0.033), larger size of practice (p?=?0.006) and high number of patients with chronic disease (p?=?0.001) were associated with a higher risk of burnout. Conclusion. Family physicians with large practices, long years of experience, a high number of chronically ill patients and experiencing chronic fatigue are at risk of developing compassion fatigue. A systematic exploration of compassion fatigue in relation to working conditions might provide an appropriate starting point for the development of preventive interventions.     

Effect of fixed-fraction subsampling on macroinvertebrate bioassessment of rivers

We investigated the effect of different subsample fractions on the variability of benthic invertebrate metrics. The results of six fractions 1/12, 1/6, 1/4, 1/3, 5/12 and 1/2 were compared to the results of the whole samples. Over 120 metrics were tested using five datasets: ecoregion Alps and four river types. In general, variability of metrics decreased with increasing subsample size, but variability varied greatly with the selected metric group and river type. Independent of river type, the highest variation was observed for the composition/abundance group metrics and the richness metrics, whereas it was low for the diversity indices and for the metrics of the sensitivity/tolerance group and intermediate for the functional metric group. For all metric groups independent of river type, the main decrease in variability occurs up to 1/4 subsample. We suggest that the effect of subsample size on variability of metrics should be tested prior to selecting potential assessment metrics.     

The StepOne real-time polymerase chain reaction detection of Salmonella sp., Salmonella enterica ser. typhimurium and enteritidis in milk and meat

The aim of this study was to follow contamination of ready to eat milk and meat products with Salmonella spp. by using the StepOne real-time polymerase chain reaction (PCR). Classical microbiological methods for detection of foodborne bacteria involve the use of pre-enrichment and/or specific enrichment, following isolation of bacteria in solid media and the final confirmation by biochemical and/or serological tests. We used the PrepSEQ Rapid Spin Sample Preparation Kit for isolation of DNA and MicroSEQ® Salmonella spp. Detection Kit for pursuance of the real-time PCR (Applied Biosystems). In samples without incubation we detected strain of Salmonella sp. in 5 out of 25 samples (swabs), as well as in the internal positive control (IPC), which was positive in all samples. This StepOne real-time PCR assay is extremely useful for any laboratory equipped by real-time PCR. It is a fast, reproducible, simple, specific and sensitive way to detect nucleic acids, which could be used in clinical diagnostic tests in the future. Our results indicated that real-time PCR assay developed in this study could sensitively detect Salmonella spp. in ready-to-eat food. This could prevent infection caused by Salmonella, and also could benefit food manufacturing companies by extending their product's shelf-life as well as saving the cost of warehousing their food products while awaiting pathogen testing results.     

Processing of whey from dairy industry waste

An investigation carried out in 11 dairies in Serbia has shows that 78.75 % of whey, a by-product of cheese industry, is emitted into river systems, thus contributing to the organic pollution of the environment. This pollution can be avoided by processing of whey into food and pharmaceuticals. It is shown that low-temperature regime of whey concentration and fractionation, based on vacuum concentration and diafiltration, preserves whey proteins undenaturated, as proved by differential scanning calorimetry method. Functional native whey proteins based food products, with potentially high immunomodulatory activity, are obtained.