National Repository of Grey Literature 28 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Plant defence against arsenic toxicity: a key role of arsenate reductase?
Jurčíková, Martina ; Mašková, Petra (advisor) ; Hála, Michal (referee)
Arsenic in its various forms is one of the most toxic environmental contaminants, which is also taken up by plants and can affect their vitality. The risk category is crops where As contamination reduces the overall yield and through which As enters the food chain. Its inorganic (arsenite and arsenate) and organic (methylated) forms are taken up by roots and rhizomes, where they can either accumulate or be translocated and subsequently stored in shoots. Arsenate reductase is an enzyme that catalyses the reduction of arsenate to arsenite, thereby affecting not only the overall toxicity of As in the plant, but also its transport between underground and aboveground organs. However, the interplay of the different mechanisms of As uptake, translocation and detoxification has not been investigated in detail. The aim of this bachelor thesis was to analyze and compare the importance of arsenate reductase in these processes in the model organism Arabidopsis thaliana, in a rice crop and in the arsenic hyperaccumulator Pteris vittata. The different tolerance of these organisms to As and their differences in the preferential site of As deposition in leaves or seeds could be used for different purposes, such as in the phytoremediation of As-contaminated soils, or in limiting the uptake or translocation of As to...
Development of cereal products for specifc nutrition with addition of fruits and vegetables
Růžičková, Magdalena ; Kubalová, Michaela (referee) ; Bendová, Agáta (advisor)
This bachelor thesis focuses on developing gluten-free cereal products for special nutrition. The main focus is on increasing the concentration of phenolic compounds and antioxidants in cereals by adding fruit and vegetable components. The theoretical part includes findings from professional literature on cereals, gluten-free cereals and their chemical composition. A chapter devoted to celiac disease and gluten-free diet was also included. Furthermore, the theoretical part focuses on possible methods of enrichment and also on selected fruits and vegetables used in the experimental part. In the experimental part, five samples of gluten-free cereals were analysed, namely black, red, brown and white rice and corn. The concentration of flavonoids, polyphenols, antioxidants, carbohydrates, proteins, -carotenes, anthocyanins, gluten, -glucans, fatty acids and lipophilic vitamins was determined in the cereal samples. Selected samples were also tested for antimicrobial activity. The black rice sample showed the best results in the majority of the measurements. Selected samples of eight types of fruit (cranberry, raspberry, strawberry, blueberry, blackcurrant, mango, banana, kiwi) and four types of vegetables (broccoli, carrot, green pea, beetroot) were also analysed. The concentration of flavonoids, polyphenols, antioxidants, carotenes, anthocyanins, ascorbic acid and lipophilic vitamins was determined in these samples. Antimicrobial tests were performed on selected fruit and vegetable samples Among the fruit samples, the best results in the majority of measurements were in blueberry and blackcurrant samples. Among the vegetable samples, the best results were obtained from the beetroot sample. From the best cereal, fruit and vegetable samples were created porridges as a final product. In these samples, the concentration of polyphenols and antioxidants was determined. The highest concentration of both compounds was found in the porridge with black rice and blueberry.
Obilniny ve výuce geografie zemědělství
DOČEKAL, Lukáš
The aim of the bachelor thesis is to create teaching texts for teaching the geography of cereals, namely for teaching at universities, upper-secondary schools and elementary schools. First, the individual cereals grown in the world are presented in detail - their botanical and morphological characteristics, their origin, development and breeding, followed by a description of the use of cereal products, the characteristics of natural conditions and agro-techniques of cereals and the geographical distribution of cereals in the world. Part of the bachelor's thesis is also an analysis of university, upper-secondary and elementary school textbooks containing the subject of the geography of agriculture, which are subsequently used in the creation of teaching texts. Tables, maps and extensive literature are part of the bachelor thesis.
Characterization of waste rice substrates and their potential utilization by microorganisms
Kapar, Jiří ; Duroňová, Kateřina (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis was to characterize some cereal substrates. Based on the results of group parameters the most suitable substrate for cultivation of model industrial microorganisms was proposed. Analysis of total phenolics, reducing sugars and total sugars was performed spectrophotometrically. Using high-performance liquid chromatography with refractometry index detection content of individual mono-and disaccharides was measured. Saccharides were extracted from cereal substrates by water and then acid hydrolysis was applied. Two rice substrates were then used as nutrition sources for cultivation of two model industrial microorganisms: yeast Rhodotorula glutinis and bacterium Bacillus subtilis. Before use to production media substrates were processed by chemical and enzyme hydrolysis and analyzed. Production of microbial biomass in media with modified waste substrates was evaluated.
Wireless transmission interference modeling (AWGN, Rayleigh, Rice fading channels)
Hloušek, Tomáš ; Gleissner, Filip (referee) ; Mikulka, Jan (advisor)
This thesis describes and models wirelesss transmission intereferences in real communication channels. A signal received on a fading channel is subjected to a multiplicative distortion and to the usual additive noise. Real channel adds to the signal noise and fadings. Gaussian noise is a result of channel awgn. Fadings is implicated by multipath propagation of signal in Rayleigh and Rician channels. Main goal of this project is to program BERsolve, which is created in tool GUIDE in Matlab. User program BERsolve makes it possible to analyse bit error rate and symbol error rate for some types of channel models, which are defined by standard COST207. BERsolve offers some other functions i.e. display time behaviour, constellation diagram and spectrum. This program provides us with an overview representation of problem by multipath interferences in communication channels.
Channel estimation in CDMA systems
Kadlec, Petr ; Prokopec, Jan (referee) ; Kejík, Petr (advisor)
The subject of this work deals with the problem of channel estimation for CDMA systems. This method of multiple access when individual users share the same full bandwidth simultaneously and are differentiated with any of pseudorandom sequences, is now the most perspective method. That is proved by its wide implementation in mobile networks of the third generation and higher systems. This work describes basic theory principles of spread spectrum, above all DS-CDMA (Direct Sequence-CDMA) and furthermore some phenomena of radio wireless channel that affect changes in transmitted signal in its way from transmitter to receiver. Terms of fading, multipath propagation, loss, refraction, scattering of the wave and Rice and Rayleigh probability density functions are mentioned. The third chapter deals with yet known and used capabilities of channel estimation. Differences, advantages and disadvantages of so-called blind estimation or training-based estimation are discussed. Two algorithms: LS method and sliding correlator are analyzed in more detail. There is also description of their simulations in Matlab and some results of these simulations are discussed. The last chapter deals with comparison of main characteristics and achievable accuracy of wireless channel impulse response estimation by both methods, and their possible utilization in real live.
Analysis of some active substances in different products from rice
Valentová, Radka ; Melounová, Jitka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis is focused on analysis of selected biologically active substances in different kinds of natural and peeled rice. In rice samples phenolic compounds, antioxidant activity, content of saccharides and vitamin C were analysed. Active substances and saccharides were analysed by UV-VIS spectrophotometry and RP-HPLC-UV/VIS. Content of phenolic compounds and saccharides was measured before and after acid hydrolysis. The content of these compounds increased several times because of release of active substances from glycosides. As a part of diploma thesis basic sensory analysis was performed and consumer questionnaires were evaluated. The highest level of antioxidant activity was detected in Indian Wild rice. The highest content of total polyphenols and flavonoids was detected in Red Rice Natural before acid hydrolysis. After acid hydrolysis the highest content was detected in Indian Wild rice. The highest content of individual flavonoids, phenolic acids and catechins was detected in natural rice Indian Wild, Rice Three colours and in two samples of rice parboiled. The highest content of total and reducing saccharides was found in rice Indian Wild before hydrolysis, while after hydrolysis the content was very similar in all rice samples. The amount of individual monosaccharides after acid hydrolysis increased, while total content of disaccharides decreased. The highest value of simple sugars was detected in rice parboiled and Indian Wild rice. The content of vitamin C was detected only in four rice kinds - in two samples of rice parboiled, Rice Three colours and rice Indian Wild.
Simulation of the Transmission Channels for the Digital Television DVB-T/H
Kučera, Jan ; Ulovec,, Karel (referee) ; Kratochvíl, Tomáš (advisor)
This thesis focuses on analysis, classification, simulation and assessment of the signal fading in the scope of terrestrial digital television reception. This is a phenomenon associated with signal multipath propagation caused by the reflection, dispersion and diffraction of electromagnetic waves in interaction with relief and artificial obstacles. Wave propagation issues in a specific landscape are not the central theme of this project. Signal transmission between the transmitter and receiver is defined by channel profile models. Attention is directed not only to static reception but also to portable and mobile reception. Simulation of this phenomenon takes place in the software environment of MATLAB. In the framework of this project program fundament was created which allows simulate the signal processing across the entire communication chain of television broadcasting, including its transmitting and receiving parts.
Potential of genetic engineering for breeding plants tolerant to abiotic stresses: cold resistance in rice
Lotová, Gabriela ; Lipavská, Helena (advisor) ; Janská, Anna (referee)
With increasing population and climate change, there has been an increase in efforts to breed more efficient crops. Genetic engineering has opened unprecedented breeding possibilities in developing plants with desired traits. Transgenic crops with better qualities, including resistance to adverse environmental conditions, can contribute to solving problems of hunger and malnutrition in developing countries. Although society perceives genetically modified crops rather negatively, these crops are widely used as feed for livestock and outside Europe also for human nutrition. Because of the complexity of resistance to abiotic stress, the utility of genetic manipulations for the breeding of resistant plants was previously not anticipated. However, it turned out that modification of the stress signalling cascade or transcription factors can lead to success. This thesis summarizes the possibilities of genetic modification of crops, which may result in better tolerance to cold, and is mainly focused on rice. Part of the work deals with transduction of cold signal, whose modification can also result in increased tolerance to cold. Another part deals with transcription factors that activate expression of low temperature- resistant genes. The greatest attention is paid to CBF/DREB transcription factors that...
Evaluation of functional properties of selected vegetable flours
VÍTKOVÁ, Věra
This bachelor thesis deals with basic structure, nutritional properties, production and use of flours. There are information about cereals and legumes, which are used for productions of flours. This thesis talks about food intolerances, which can be a reason why change basic flours of wheat, barley, oat and rye to another. Practical part is about 14 flours, which were tested on dry matter, humidity, nitrogen substances content, proteins, protein electrophoretic profiles (patterns), solubility, water and fat holding capacity, formation of gels and changes of colours during a boiling. The results of this research are information about nutrition and functional properties of tested flours.

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