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Detection of paroxysmal atrial fibrillation and atrial flutter
Krmela, Jan ; Němcová, Andrea (referee) ; Smíšek, Radovan (advisor)
This bachelor thesis deals with the problem of atrial fibrillation and flutter, the pathophysiology of these arrhythmias and their automatic detection. It includes a theoretical introduction necessary to understand the basal anatomy of the heart, its function, the origin and description of the electrocardiogram and a chapter on cardiac arrhythmias. It also includes a review of automatic detection of atrial fibrillation. The databases used in the practical part of the thesis are also described. The implementation of heart rhythm classification and automatic detection of the beginning and end of paroxysmal episodes is performed in MATLAB environment, the proposed algorithm is tested on the described databases and the results are evaluated.
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Robust detection of systolic peaks in PPG signal
Gálík, Pavel ; Smital, Lukáš (referee) ; Němcová, Andrea (advisor)
This bachelor thesis deals with systolic peak detection and their usage within the PPG signal. PPG signal is widely used by portable devices like smartwatch which contributes to monitoring of vital functions during the day. The theoretical part describes heart morphology and ECG signal development which is related to PPG. Furthermore, the PPG signal is described together with its usage and recording methods. Other part describes chosen methods for systolic peak detection. The practical aim of this bachelor’s thesis is to record data and to create own PPG signal database. ECG signal has been recorded as a referential value. The algorithm for systolic peak detection has been developed and tested. In conclusion achieved results are discussed with findings of different authors.
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Application of microbial oils in cosmetics
Reichertová, Klára ; Uhlířová, Renata (referee) ; Němcová, Andrea (advisor)
This bachelor thesis is focused on the application of microbial oil in a cosmetic product. Eight strains of yeasts of the genus Metschnikowia were examined, namely Metschnikowia pulcherrima 145, Metschnikowia pulcherrima 147, Metschnikowia pulcherrima 149, Metschnikowia andauensis 129, Metschnikowia andauensis 1241, Metschnikowia sinensis 1244, Metschnikowia zizyphicola 1247 and Metschnikowia shanxiensis 1250 for production of microbial oil. Substrates made of technical hemp (hemp flour, hydrolyzate and a mixture of leaves and flowers) were used for cultivation. The cultivation was performed at reduced temperature with the advantage of lipid production. The composition and ratio of fatty acids were determined by gas chromatography According to these resulst was choosen the best lipid producer and the most abundant substrate. This was the strain Metschnikowia zizyphicola 1247 and the substrate of hemp flour. At the end of the practical part was prepared a cream, into which the microbial oil was mixed. Finally, an evaluation of the oil with regard to its use in cosmetics and a comparison with vegetable oil with the same fatty acid profile are given.
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Analysis of authenticity of some food products with fruit component by molecular and instrumental techniques
Pecháček, Michal ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This master’s thesis was focused on determining the authenticity of some food products with fruit component by molecular and instrumental techniques. The thesis was divided into theoretical and practical part. The theoretical part of the work was focused on food adulteration, methods of determining the food authenticity, analysed types or technologies of production of individual food products, which were analysed in this work. This part was also focused on molecular and instrumental techniques, which are currently used to determine the food authenticity. The practical part of the thesis was divided into molecular and instrumental part. Within the molecular part, DNA isolation was performed using the EliGene Plant DNA Isolation kit. Inhibitors such as polysaccharides seemed to be the biggest problem during the DNA isolation. Therefore, an isolation method using pectinase incubation was performed. The isolated DNA was subsequently subjected to PCR and the resulting PCR products were analysed by a melting curve analysis. This method was used for ITS2 primers, which were used for the plant DNA detection. In the case of species-specific primers BAS1 and Pa3LTP that were used for the peach and apricot detection, high resolution melting (HRM) analysis was performed. During HRM, the focus was on the melting temperature of the specific PCR products. The melting temperature of the BAS1 specific product was set at 78,4 °C and at 86,43 °C for the specific product of Pa3LTP primers. Finally, specific PCR products were subjected to agarose gel electrophoresis. In the case of ITS2 primers, which served to verify the amplifiability of plant DNA, a band of 500 bp was detected. In the case of species-specific primers BAS1 and Pa3LTP, bands from 100 to 150 bp were detected. In the instrumental part of this thesis the HPLC/PDA analysis of the phenolic compounds was performed. The most suitable procedure for the analysis of phenolic substances was the purification procedure using ethanol without further concentration At the end of the work, the individual methods were compared with each other. At the same time, the influence of the matrix on the overall determination of food authenticity was monitored. While molecular techniques could be used to determine the food authenticity by determining the presence of specific DNA, instrumental techniques would be more suitable for detecting food adulteration and detecting specific substances.
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Sensory quality of French cheese Brie de Meaux in connection with chemical and microbial composition
Májková, Monika ; Němcová, Andrea (referee) ; Vítová, Eva (advisor)
This thesis deals with the assessment of the effect of storage of French Brie de Meaux (AOC) on its volatile (aromatic) compounds, free and bound fatty acids and microbial composition, in relation to its sensory quality. The theoretical part is devoted to cheeses with white mould on the surface. In the experimental part, the influence of temperature and storage time on the sensory quality and safety of cheese is assessed. In the storage experiment, the cheeses were stored for 21 days at 5 °C (one bulk, one vacuumed) and at 20 °C. The samples were evaluated by SPME-GC-MS for volatile (aromatic) compounds. Fatty acids were identified and quantified by GC-FID after conversion to methyl esters using BF3. RT-PCR method was used for microbial profile. Fifty-nine volatile compounds were identified in the samples and contribute to the flavour characteristics of the cheese. Among the fatty acids, palmitic, oleic, myristic and stearic acids were predominant. The microbial profile confirmed Micrococcus luteus as a contaminant in cheese stored at 20°C, while the other contaminants were not detected positively. From a sensory point of view, the standard cheese (analysed immediately after purchase) together with cheese stored at 5 °C in vacuum form for 21 days was the best performing cheese.
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Monitoring the nutritional profile of edible fats and oils after culinary treatments
Chadimová, Markéta ; Vítová, Eva (referee) ; Němcová, Andrea (advisor)
This diploma thesis studies changes in the nutritional composition (especially fat changes) of selected fats and oils after various culinary treatments and during their storage under unsuitable conditions. Fats and oils are classified as so-called triacylglycerols, ie they are composed of glycerol and three fatty acids. It is the fatty acids bound to glycerol that determine the properties of fat and its stability. Eight types of fats and oils (sunflower oil, rapeseed oil, olive oil, coconut oil, linseed oil, butter, ghee and lard) were used for the analysis. The flaxseed oil sample was stored for 3 months in unfavorable storage conditions, ie in the light and in the heat. Other fats and oils were used for frying, baking, stewing, grilling and frying meat and onions. The aim of the work was to compare changes of fatty acids, changes of fat numbers and compare the amount of vitamin E contained in individual oils before and after culinary treatments. The results of the analysis showed that fat samples did not show significant changes in fat numbers, fatty acids or vitamin E after culinary treatments or improper storage. From this I conclude that fats and oils have been exposed to high temperatures and unsuitable conditions for a short time. The largest difference in the composition of fatty acids was measured for sunflower oil, where a higher amount of trans fatty acids was measured after treatment and overall a lower proportion of PUFA was measured than before treatment. As sunflower oil has a high content of polyunsaturated MK and a low smoke point, this result was expected. The highest concentration of vitamin E was found in rapeseed oil.
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Influence of clinical nutrition in elderly patients
Jančarová, Kateřina ; Matejovičová,, Milena (referee) ; Němcová, Andrea (advisor)
This master’s thesis deal with the influence of supplementation with omega-3 fatty acids on cognitive functions and on the blood marker of clients in the retirement home. The main target of this thesis is demonstrate the improvement of cognitive functions and lipid and glycemic profile after supplementation with the dietary supplement. Suplementation was serve to the clients for the period of 3 months 3 times a day in the amount of 5 ml per dose. In the teoretical part of the thesis was explained the process of aging and the problematics of omega-3 fatty acids. The practical part evaluates the three-month supplementation with a dietary supplement and its mainly focus to cognitive tests MMSE and blood test results. The thesis is deal with effect of the product on the blood marker, mainly the lipid profile and glycemic profile were determined. Laboratory analysis was used to determine lipid numbers. Fatty acids analysis was performed by gas chromatography and vitamins analysis was performed by liquid chromatography. Based on recent findings, it was assumed that supplementation of omega-3 fatty acids can improve the cognitive functions in older adults as well as their lipid and glycemic profile. The improvements have been confirmed in cognitive functions but not in lipid profile. This facts may have been influenced by several factors, such as inappropriate composition of the menu, the consumption of foods with a high content of saturated fatty acids outside the menu, the administration of medication or overall short supplementation time period.
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Monitoring the influence of stress factors on yeasts of the genus Metschnikowia using molecular techniques
Kuljovská, Tereza ; Kovalčík, Adriána (referee) ; Němcová, Andrea (advisor)
Molecular techniques are used widely nowadays, especially in the identification of various species of microorganisms, and provide reliable and accurate results in a relatively short period of time. This work deals with the characterization of Metschnikowia yeasts exposed to various stress factors and the monitoring of their genomic DNA by PCR-DGGE and PFGE methods. The work was focused on the analysis of ribosomal rDNA, specifically the ITS1 and 5,8-ITS2 regions and genes encoding the domains D1/D2, that are part of the large 26S rDNA ribosomal subunit, which are commonly used in the characterization of fungal eukaryotic communities. Three types of stress factors were selected for the experiments: osmotic stress (NaCl environment), oxidative stress (addition of H2O2 to the medium) and nutritional stress (addition of hemp flour / leaves and flowers as a carbon source). The analysis was performed for particular strains Metschnikowia andauensis, Metschnikowia pulcherrima, M. chrysoperlae, M. shanxiensis, M. sinensis and M. zizyphicola. The results showed that addition of the NaCl, H2O2 and hemp components at higher concentrations to the production media does not disrupt the ribosomal DNA when detected by PCR-DGGE. Mutations have not been observed by comparing these strains with yeast that was cultivated under optimal conditions. Despite stress factors, PFGE analysis of karyotypes showed that DNA of some yeast species does not prove any damage and remain intact. Remaining strains proved certain degree of damage, and bands were not detected on the gel for these strains. In the given circumstances, it can be stated that the high adaptability of these species to a stress environment makes them promising biotechnology producers. These yeasts have great potential for usage in agriculture as a tool for biocontrolling of fruit or vines.
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Encapsulation of active substances and possibilities of their application in anti-aging products
Horváthová, Iveta ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aims of this thesis were encapsulation of selected active substances and their possible application in cosmetic products with anti-aging effects. 6 kinds of active substances were studied – lipophilic vitamin E and vitamin A, hydrophilic vitamin B1 and vitamin B2, and phenolic compounds ferulic acid and chlorogenic acid. In theoretocal part, the general characteristics of active compounds and their use are described. It also includes the description of used methods. Practical part was focused on characterisation of active compounds from the perspective of antioxidant activity and encapsulation into liposomes from soy and sunflower lecithin. Encapsulation effectivity, size, stability and long-term stability of liposomes after four weeks were determined. The most suitable liposomes with active compounds were also tested for safety on human skin cells using the MTT test of cytotoxicity on keratinocytes HaCaT. Furthernore, 3 types of cosmetic products were prepared – day cream, night cream and skin serum. Each kind of cosmetic product was devided into 4 types – the product without any active compounds, the product containing free active compounds, the product with liposomes with active compouds and the product containing empty liposomes. As active compounds all our tested substances were used. Final products were tested 14 days on 15 female volunteers. Before and after products usage parametres of their skin were measured to analyze effect of products on skin rejuvenation. Volunteers were also rating sensory analysis of cosmetic products. The part of this thesis was also creating an online questionnaire about anti-aging cosmetics for publicity to find out the popularity of this kind of cosmetics.
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