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Belt conveyors - theory and design
Žáček, Petr ; Pokorný, Přemysl (referee) ; Malášek, Jiří (advisor)
This bachelor’s thesis deals about the calculation and design of belt conveyors with focusing also on the atypical design solutions. Contains the basic classification, design solutions and complex calculation of belt conveyors. Also contains an overview of producers of purchased parts and units.
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Use of the modern separation techniques for the analysis of insect pheromones
Žáček, Petr ; Jelínek, Ivan (advisor) ; Pacáková, Věra (referee) ; Cvačka, Josef (referee)
(EN) Communication mediated by chemical compounds (semiochemicals) is the most important way of information transfer in insects, especially in the social species. Gas chromatographic methods (one-dimensional, two-dimensional comprehensive, and preparative arrangement) coupled with mass spectrometric and/or electroantennographic detector were used for volatile or semivolatile semiochemicals analysis in various insect species. In this Thesis, biosynthesis of the bumblebee male sex pheromone in species Bombus terrestris, B. lucorum, and B. lapidarius was studied using putative biosynthetic precursors (sodium acetate, fatty acids) labeled with 2 H and 14 C. For the purpose of labeled volatile metabolites analysis, a method of separation and detection of isotopically labeled compounds in two-dimensional comprehensive gas chromatography was studied (2 H, 13 C). An "inverse isotope effects" was confirmed for compounds labeled with both isotopes in all examined types of columns. Concerning the biological samples, analysis of in vitro incubated tissues with labeled sodium acetate showed that pheromone components are synthesized de novo in the labial gland in B. terrestris and B. lucorum. Nevertheless, experiments of in vivo incubation of deuterated fatty acids confirmed biotransformation of the precursors...
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Preparation of affinity surfaces for clinical diagnostics
Kalaninová, Zuzana ; Pompach, Petr (advisor) ; Žáček, Petr (referee)
Botulinum toxins are group of protein venoms produced by Clostridium bacteria. These toxins belong to the most toxic substances causing paralytic disease called botulism. The endopeptidase activity of the toxins leads to the blockage of neurotransmitters release to neural junctions. Since the first symptoms of botulism are observed within 48 hours and toxin remains active for months, botulinum toxins are considered as potential bio- terrorism agents. For successful treatment, fast assays for detection of the toxin presence and type are highly required. This work presents a new method that could be potentially used for determination of botulotoxin in various matrices. The method is based on the detection of products of botulinum toxin A (BoNT/A) endopeptidase activity by affinity surfaces prepared by ambient ion soft landing and MALDI mass spectrometry. For immobilization and subsequent enrichment of biotinylated products of BoNT/A activity, proteins with high affinity to biotin - avidin, neutravidin and streptavidin - were used. The presented method, which combines affinity surfaces with MALDI mass spectrometry is sensitive, robust and fast and might be potentially used for detection of BoNT/A activity. Key words: ambient ion soft landing, neutravidin, botulinum toxin A, BoNT/A, MALDI/TOF mass...
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Analysis of a human body odour using comprehensive two-dimensional gas chromatography
Bušovská, Radka ; Sobotníková, Jana (advisor) ; Žáček, Petr (referee)
Body odour perception plays an important role in human mate choice, especially in women. It was previously proposed that women select partners whose body odour resembles that of woman's fathers. Yet, this phenomenon has only been confirmed using ethological studies based on subjective perception of body odour similarities. Therefore, the aim of my diploma thesis was to test this hypothesis instrumentally using comprehensive GC×GC-TOFMS and subsequent multidimensional analyses of body odour chemical profiles of male partners and fathers of adult women. Body odour sampling from left and right axilla of fathers and partners of 41 women (altogether 164 samples) was performed using cotton swabs, which were then frozen and extracted into hexane. Typical human volatile substances, such as hydrocarbons, carboxylic acids, esters, alcohols, aldehydes, ketones, sterols and terpenes were detected in all examined samples. Using a newly available "tile-based" chromatographic alignment algorithm, we obtained a set of 341 compounds systematically occurring in male axillary odour. The principal component analysis was used to calculate Euclidean distances for all pairs of the studied male subjects. These estimates of "chemical distances" revealed to be significantly smaller for father-partner pairs of individual...
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Use of the modern separation techniques for the analysis of insect pheromones
Žáček, Petr
(EN) Communication mediated by chemical compounds (semiochemicals) is the most important way of information transfer in insects, especially in the social species. Gas chromatographic methods (one-dimensional, two-dimensional comprehensive, and preparative arrangement) coupled with mass spectrometric and/or electroantennographic detector were used for volatile or semivolatile semiochemicals analysis in various insect species. In this Thesis, biosynthesis of the bumblebee male sex pheromone in species Bombus terrestris, B. lucorum, and B. lapidarius was studied using putative biosynthetic precursors (sodium acetate, fatty acids) labeled with 2 H and 14 C. For the purpose of labeled volatile metabolites analysis, a method of separation and detection of isotopically labeled compounds in two-dimensional comprehensive gas chromatography was studied (2 H, 13 C). An "inverse isotope effects" was confirmed for compounds labeled with both isotopes in all examined types of columns. Concerning the biological samples, analysis of in vitro incubated tissues with labeled sodium acetate showed that pheromone components are synthesized de novo in the labial gland in B. terrestris and B. lucorum. Nevertheless, experiments of in vivo incubation of deuterated fatty acids confirmed biotransformation of the precursors...
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Preparation of affinity surfaces for clinical diagnostics
Kalaninová, Zuzana ; Pompach, Petr (advisor) ; Žáček, Petr (referee)
Botulinum toxins are group of protein venoms produced by Clostridium bacteria. These toxins belong to the most toxic substances causing paralytic disease called botulism. The endopeptidase activity of the toxins leads to the blockage of neurotransmitters release to neural junctions. Since the first symptoms of botulism are observed within 48 hours and toxin remains active for months, botulinum toxins are considered as potential bio- terrorism agents. For successful treatment, fast assays for detection of the toxin presence and type are highly required. This work presents a new method that could be potentially used for determination of botulotoxin in various matrices. The method is based on the detection of products of botulinum toxin A (BoNT/A) endopeptidase activity by affinity surfaces prepared by ambient ion soft landing and MALDI mass spectrometry. For immobilization and subsequent enrichment of biotinylated products of BoNT/A activity, proteins with high affinity to biotin - avidin, neutravidin and streptavidin - were used. The presented method, which combines affinity surfaces with MALDI mass spectrometry is sensitive, robust and fast and might be potentially used for detection of BoNT/A activity. Key words: ambient ion soft landing, neutravidin, botulinum toxin A, BoNT/A, MALDI/TOF mass...
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Use of the modern separation techniques for the analysis of insect pheromones
Žáček, Petr
(EN) Communication mediated by chemical compounds (semiochemicals) is the most important way of information transfer in insects, especially in the social species. Gas chromatographic methods (one-dimensional, two-dimensional comprehensive, and preparative arrangement) coupled with mass spectrometric and/or electroantennographic detector were used for volatile or semivolatile semiochemicals analysis in various insect species. In this Thesis, biosynthesis of the bumblebee male sex pheromone in species Bombus terrestris, B. lucorum, and B. lapidarius was studied using putative biosynthetic precursors (sodium acetate, fatty acids) labeled with 2 H and 14 C. For the purpose of labeled volatile metabolites analysis, a method of separation and detection of isotopically labeled compounds in two-dimensional comprehensive gas chromatography was studied (2 H, 13 C). An "inverse isotope effects" was confirmed for compounds labeled with both isotopes in all examined types of columns. Concerning the biological samples, analysis of in vitro incubated tissues with labeled sodium acetate showed that pheromone components are synthesized de novo in the labial gland in B. terrestris and B. lucorum. Nevertheless, experiments of in vivo incubation of deuterated fatty acids confirmed biotransformation of the precursors...
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Use of the modern separation techniques for the analysis of insect pheromones
Žáček, Petr ; Jelínek, Ivan (advisor) ; Pacáková, Věra (referee) ; Cvačka, Josef (referee)
(EN) Communication mediated by chemical compounds (semiochemicals) is the most important way of information transfer in insects, especially in the social species. Gas chromatographic methods (one-dimensional, two-dimensional comprehensive, and preparative arrangement) coupled with mass spectrometric and/or electroantennographic detector were used for volatile or semivolatile semiochemicals analysis in various insect species. In this Thesis, biosynthesis of the bumblebee male sex pheromone in species Bombus terrestris, B. lucorum, and B. lapidarius was studied using putative biosynthetic precursors (sodium acetate, fatty acids) labeled with 2 H and 14 C. For the purpose of labeled volatile metabolites analysis, a method of separation and detection of isotopically labeled compounds in two-dimensional comprehensive gas chromatography was studied (2 H, 13 C). An "inverse isotope effects" was confirmed for compounds labeled with both isotopes in all examined types of columns. Concerning the biological samples, analysis of in vitro incubated tissues with labeled sodium acetate showed that pheromone components are synthesized de novo in the labial gland in B. terrestris and B. lucorum. Nevertheless, experiments of in vivo incubation of deuterated fatty acids confirmed biotransformation of the precursors...
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