National Repository of Grey Literature 58 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Evaluation of the effects of biodegradable microplastics on biota of freshwater ecosystem via ecotoxicity tests
Procházková, Petra ; Maršálek,, Blahoslav (referee) ; Beklová, Miroslava (referee) ; Zlámalová Gargošová, Helena (advisor)
Microplastics, which are ubiquitous contaminants of freshwater ecosystems, have raised concerns regarding their potential impact on the environment. For this reason, there is an effort to replace conventional plastics with biodegradable alternatives that can easily degrade in the environment. However, the process of biodegradation of these materials requires specific conditions, such as temperature, humidity, pH, and the presence of microorganisms, which are not always met adequately. Consequently, they may fragment and form biodegradable microplastics that can affect the environment similarly to conventional microplastics. Therefore, the aim of this study was to assess the impact of microplastics of biodegradable poly(3-hydroxybutyrate) microplastics on freshwater organisms, specifically the alga Desmodesmus subspicatus, the plant Lemna minor and the crustacean Daphnia magna. Additionally, we aimed to develop a suitable analytical method for the direct detection of microplastics in the body of D. magna. Although the observed effects were not always significant, they highlighted certain secondary problems that may arise due to the presence of biodegradable microplastics in the environment These issues could be related to biodegradability and the formation of biofilm on the surface of biodegradable microplastics, leading to subsequent nutrient depletion in the surrounding environment. Therefore, the use of biodegradable plastics as a substitute for conventional materials must be approached critically.
Influence of advanced oxidative processess on ecotoxicity of pesticides
Goma, Bernadette ; Procházková, Petra (referee) ; Zlámalová Gargošová, Helena (advisor)
The topic of this bachelor thesis is a study of the influence of advanced oxidation processes on the ecotoxicity of pesticides Metazachlor and Chloridazon. Both herbicides are commonly used to protect crops such as oilseed rape, turnips, chard or fodder beet against whole range of undesirable monocotyledonous and dicotyledonous plants. Application is most often on large areas and therefore pose a high risk to the quality of the environment. The possible influence on the representatives of producers and consumers of the aquatic ecosystem was monitored in the work. Solutions of pesticides, which were subjected to selected methods of treatment using advanced oxidation processes, were tested on aquatic organisms, specifically on crustaceans Daphnia magna and aquatic plant Lemna minor. From the results of individual tests, the ecotoxicological values of EC50 and IC50 were calculated and their ecotoxicity and thus the efficiency of oxidation processes in the removal of pollutants from wastewater were compared.
Ecotoxicity tests on cellular level
Procházková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Endocrine disrupting compounds among significant environmental pollutants. They are dangerous both for humans and other organisms by affect their hormonal system. They enter the environment during production, use and disposal some chemicals, but they may be of natural origin. The aim of this work is to give a brief overview of possible methods of determination of the presence of ecotoxic substances in the environment, using the in vitro toxicity assays. These tests use cell cultures instead of test organisms. The work describes principles of ecotoxicity tests at the cellular level, such as cell viability assays, cell proliferation assays, assays based on the metabolic activity of cells or DNA microarrays. A significant part of this work is focused on the possibilities of determination of endocrine disruptors by selected assays. They are ligand binding assays, reporter gene assays (recombinant yeast assay, mammalian-based reporter gene assays) and cell proliferation assay called E-screen. Significance and rationale use of tests to prove the endocrine activities in environmental matrice is given through examples of studies in which the tests were used.
Assessment of the effectiveness of advanced oxidation processes via ecotoxicity tests
Procházková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Recently, an increasing problem in wastewater treatment is the insufficient removal of organic pollutants. These substances can be toxic to the environment already in a small amount, either acutely or chronically. The goal is therefore to develop of technologies that ensure their effective removal. One possibility is to use advanced oxidation processes. Advanced oxidation processes work on the principle of non-selective oxidation mediated by OH radicals. Several methods such as O3/H2O2 (Peroxone), UV/H2O2 or Fenton´s reaction can be used to generate them. The aim of this thesis was to evaluate the effectiveness of the used advanced oxidation processes in wastewater treatment via ekotoxicity tests. Wastewater samples treated with advanced oxidation processes on the pilot unit showed low values of acute toxicity for selected test organisms (D. magna, T. platyurus, S. alba, L. minor). For the sample of waste water that was treated with the UV/H2O2 on AOP laboratory unit, there was an increase in acute toxicity on the testing organism D. magna and L. minor. The similar effect was observer in the tests with the D. magna with the model samples treated with the same method, while the tests on the L. minor showed a reduction in toxicity.
The Business Plan for the Foundation of a Kindergarten
Soukupová, Šárka ; Procházková, Petra (referee) ; Bayerová, Vladimíra (advisor)
The master´s thesis is the proposal of the business plan for the foundation of a private kindergarten in Ivančice, as a limited liability company. The proposal is based on market needs and analysis of general and business environment, for which is typical the excess demand for services of kindergartens over their existing capacities. Organizational, marketing and especially financial plan backs up viability selected business.
Ecotoxicological evaluation of biochar via organism Folsomia candida
Marcinko, Juraj ; Procházková, Petra (referee) ; Zlámalová Gargošová, Helena (advisor)
The aim of this bachelor thesis was to ecotoxicologically evaluate selected biochar samples and to assess, using a test organism, the possible long-term and short-term effects on soil invertebrates. One of the possible uses of biomass is to convert it into biochar with subsequent application to soil. Soil fauna may be affected after biochar application, therefore ecotoxicological tests in a contact arrangement were chosen. Folsomia candida was used as the test organism. Short-term effects were recorded through escape tests, specifically low abundance of organisms in samples (I) and (T). Significant preference of organisms was observed for sample (O). Samples (I) and (T) had a further impact on the survival of organisms and on the quality of reproduction, where in some cases this caused a resolute impact. Sample (O), at different concentration levels, had no effect on the test organisms. The results of these tests approximate how soil invertebrates could be affected after biochar application.
Evaluation of the Financial Situation in the Firm and Proposals to its Improvement
Geletová, Miroslava ; Procházková, Petra (referee) ; Karas, Michal (advisor)
This bachelor’s thesis analyses the financial situation of company COMINFO, a.s. between the years of 2011-2014, with the use of chosen methods of financial analysis. Based on the results, the financial situation of the company is collectively evaluated and then recommendations are designed, that could improve current financial situation of the company.
Application of Gender Management in Selected Company
Brabcová, Zdeňka ; Procházková, Petra (referee) ; Rašticová, Martina (advisor)
This diploma thesis is focused on the application of gender management in Bosch Diesel company, situated in Jihlava. In the theoretical part the essential terms and general findings about gender management and work-life balance are explained. The practical part of the thesis deals with the chosen company, analysis of its internal environment and incentives to integrate gender management and deal with the work-life balance. Alongside with the survey in Bosch Diesel, questionnaire research in Honeywell (Brno) was accomplished, which provided an interesting comparison with the questionnaire investigation carried out in Bosch Diesel. The aim of the thesis is to prepare suitable suggestions based on the previous analysis. These suggestions are of informational character and then they could bring positive changes in some companies (and the whole society as well).
The Proposal of Motivation System in the Mining Company
Dubnický, Marek ; Procházková, Petra (referee) ; Mucha, Martin (advisor)
This bachelor thesis deals with a shortcomings of motivational system of employees in the company Hornonitrianske bane Prievidza a.s. The introductory part summarizes the theoretical knowledge and the second part includes familiarization with the company and actual manpower analysis. Consequently based on analysis I suggest a solution which would be optimal for management and simultaneously for employees.
Evaluation of the efficiency of root treatment plants via ecotoxicity tests
Konečná, Kateřina ; Procházková, Petra (referee) ; Zlámalová Gargošová, Helena (advisor)
This bachelor thesis focuses on the evaluation of the efficiency of root treatment plants using appropriately selected ecotoxicity tests. For these purposes, ecotoxicological tests in an aquatic arrangement were used, specifically with the planktonic organism Thamnocephalus platyurus and the plant Lemna minor. The evaluation was performed at a municipal root treatment plant, which treats water for 955 equivalent inhabitants. The results of tests with T. platyurus confirmed that the root treatment plant sufficiently relieves acute toxicity of water. LC50 values were determined for two samples, 213.71 ml / l for the inflow and 388.20 ml / l for the settling tank. At the outflow, these values could no longer be determined due to the low ecotoxicological effect of the water thus treated. For tests with L. minor, IC50 values were also calculated for the first two samples. For Sample No. 1, the IC50 value was calculated to be 311.25 ml / l, for Sample No. 2 to 963.35 ml / l. However, on the basis of tests of direct toxicity of waters with L. minor, it is possible to confirm even in the case of this organism, a good cleansing effect of this root treatment plant.

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