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Content of cesium-137 in fungi in selected localities in the Novohradské hory
SCHNEIDEROVÁ, Kateřina
The Novohradské Mountains were increasingly contaminated with cesium-137 in places where large amounts of radiocesium were washed out of the radioactive cloud caused by the accident of the Chernobyl nuclear power plant on April 26, 1986. Another source of cesium-137 was the testing of nuclear weapons, which was in the 50s and 60s of the 20th century carried out in the atmosphere of nuclear powers. From contaminated soil, cesium-137 enters the food chain and thus causes internal contamination of the population. For this reason, the activity concentration of cesium-137 in food (especially in edible mushrooms) is regularly determined. The aim of this thesis was to compare the activity concentrations of cesium-137 in samples of edible fungi collected in selected localities of the Novohradské Mountains. Transfer factors in individual fungal species were determined and compared. The thesis also focused on the comparison of the activity concentration of cesium-137 in the cap and in the stem of the mushroom. The samples were measured by gamma spectrometry. The values of activity concentration of cesium-137 in edible mushrooms differed according to their classification into the systematic group. Higher values of activity concentrations were measured in basidiomycete fungi compared to lower values recorded in gill fungi. High values of activity concentrations of cesium-137 have been repeatedly found, especially in the imleria badia (Xerocomus badius). The lowest value of the activity concentration of cesium-137 was measured in the representative of the parasol mushroom (Macrolepiota procera). The transfer factor as a ratio between the activity concentration of cesium-137 in the mushroom and the activity of cesium-137 in the soil is an important parameter for estimating the dose of internal exposure to radionuclides that a person receives in contaminated foods. The highest determined transfer factors were calculated for imleria badia (Xerocomus badius), the blusher (Amanita rubescens) and golden chanterelle mushroom (Cantharellus cibarius). Out of a total of 58 samples, in 78 % of the samples the values of the activity concentration of cesium-137 in the cap were higher than the values of the activity concentration in the stem and in 22 % of the samples the activity concentrations in the cap were lower than in its stem. The determined cap/stem ratio confirmed that three quarters of the edible mushrooms examined preferentially accumulated cesium-137 in the cap and one quarter of the mushrooms more accumulated cesium-137 more in their stem.
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Epidemiological Situation at a Pharmacy.
SCHNEIDEROVÁ, Kateřina
Airborne respiratory infections are among the most frequent diseases. Airborne respiratory infections afflict both children and adults; they can pose a potential threat to persons already suffering from another primary illness or those with impaired immunity. A disease-carrying person transpires pathogens through droplets or biological aerosol when coughing, sneezing or talking. Such ways of illness transmission pose a risk of nosocomial infection dissemination in medical facilities. The objective of this Bachelor's thesis is to quantify microbiological pollution in the indoor environment and evaluate the negative influence, if any, of bacterial contamination on the health of patients occurring at the pharmacy. The laboratory work part of the thesis aimed at the sampling, processing and identification of airborne infection agents at a medical facility (pharmacy) in the period of May 2018 to February 2019. The sampling method used was the method of passive collection (platform settling method). The principle of this method is that microorganisms present in the air settle over blood agar in a Petri dish. The factors evaluated in analyzing microbiological pollution of indoor air included the influences of air temperature and humidity at the pharmacy, as well as the number of persons present at the time of taking the sample. Pursuant to Decree n. 6/2003, which sets hygienic limits for biological indicators in indoor environments of frequented premises in medical facilities, the maximum limit is 500 CFU/m3 (CFU is a unit used to estimate the count of viable bacteria). The counts found during the review period have never reached the limit. The values measured showed that there is a certain degree of positive correlation between the air temperature, air humidity and CFU count per dish. Comparisons between the number of patients and the CFU count per dish demonstrated no distinct cross-correlation between the two factors. As far as the representations of individual groups of identified microorganisms in the samples are concerned, the G+ Staphylococcus spp. group takes a prevalent share, counting for more than 50 % of microorganisms in the samples, and as much as 75 % in some samples. G- rods follow, with a share of as much as 46 %, further followed by G+ diplococcus and tetracoccus bacteria with a share of as much as 43 %. Of the focus pathogens, the occurrence of Staphylococcus aureus and Streptococcus pyogenes were confirmed. The results of my bachelor's thesis did not confirm any overlimit microbiological pollution of the pharmacy indoor air or a significant occurrence of bacterial respiration infection agents. In conclusion, in terms of bacterial contagion, indoor air at pharmacies can be seen as a low risk.
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Physical security precautions
SCHNEIDEROVÁ, Kateřina
Creating a system of measures to prevent unauthorized person or impede access to classified information, or at least attempt to record it. You must select individuals who will have access to classified information, training and defence. Finally, we must not forget the administrative security - system measures in the production, reception, registration, processing, storage, transport and archiving of classified information.
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