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Dispersed reinforcement influence on the maturation of polymercement materials
Zaťko, Petr ; Jakubík, Aleš (referee) ; Bydžovský, Jiří (advisor)
The diploma thesis is focused on polymercement materials with dispersed reinforcement. The aim of this work is development of suitable polymercement mixture and monitoring of the impact of dispersed reinforcement on the course of maturation of these materials and physico-mechanical properties. The effect of high temperatures on the properties of the mortar is also examined. Emphasis is placed on the use of alternative resources and byproducts. Mixed binder of cement and slag and admixture of microsilica was used. Recycled cellulose was used as dispersed reinforcement and was compared with commercial polypropylene fibers.
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Development of new technology of sand autoclaved aerated concrete with using of secondary raw materials
Ondříčková, Pavlína ; Suchý, Peter (referee) ; Drochytka, Rostislav (advisor)
Autoclaved sand aerated concrete is a modern building material with high thermal insulation properties. Only sand is used as the primary silicate component of aerated concrete in the Czech Republic. For the more favourable economic and ecological properties of aerated concrete, the use of secondary raw materials is used in this work. The secondary raw materials examined included fluidized bed and fly ash, slag and glass recycled. The aerated concrete composite with secondary admixtures was developed under hydrothermal conditions of a laboratory autoclave for 7 and 12 hours at 190°C. From the secondary raw materials tested, a 10% glass recycler additive yielded the highest strength. Other additives that have a positive effect on mechanical properties include SAKO and Oslavany. From the results of the work it is evident that the use of secondary raw materials increases the strength, improves the rheology of the mixture and supports the formation of tobermorite.
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Study of fruit ripening and storage
Langová, Jiřina ; Zemanová, Jana (referee) ; Babák, Libor (advisor)
There are many changes in fruit quality during its ripening and storage. The following four apple varieties were studied: Champion, Glostr, Golden Delicious and Idaret. Amount of reducing sugars, total amount of sugars, quantities of acids, refractive solids and loss of starch were monitored. The changes of parameters, the differences between the varieties and differences in storage were compared. Parameters were monitored from mid-August 2008, when the apples ripened. After the harvest, apples were stored in a cool box at 2 - 3 ° C and at room temperature 20 - 23 ° C. Apples stored in the cool box were analyzed till the end of March 2009, and apples stored at room temperature until the beginning of January 2009. Total quantity of sugars in all varieties increases before harvest, while it decreases after picking the apples. The quantity of reducing sugars in apples rises gradually and after their picking it falls significantly in apples stored at 20 - 23 ° C. In apples stored in the cool box it continues rising until the end of November, and then it also decreases. Losses of starch are considerable and they are accelerated after the harvest. The quantity of acids also decreases throughout and amounts of refractive solids increases. For all varieties there are significant changes in storage at 20 - 23 ° C. Temperature, therefore, significantly affects processing of sugars and acids in fruit respiration.
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Aktuálna problematika zrenia mäsa vo vzťahu k očakávaniam a požiadavkám zo strany spotrebiteľa
Gago, Branislav
This work investigates the effect of aging on meat quality. The research is based on a review of current scientific literature, including studies on biochemical and sensory changes that occur during aging. In particular, i compared the effects of aging on marbling, tenderness, flavor and moisture content. Further, the effects of different aging processes such as dry aging and wet aging were discussed. In addition, the economic and health benefits of aged beef were also investigated. The results showed that aging can have a positive effect on the quality and flavor of the meat, leading to increased tenderness and marbling, as well as improved flavor and juiciness. Additionally, dry aging has been found to be more effective in increasing beef quality compared to wet aging. Finally, the economic and health benefits of ripening were emphasized.
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The role of cumulus cells during the maturation of mammalian oocytes
Meniuková, Kateřina ; Krylov, Vladimír (advisor) ; Drutovič, David (referee)
Cumulus cells in the ovarian follicles emerge by differentiation from somatic granulosa cells. They are located around the oocytes in stratified clusters and their innermost layer is called the corona radiata. Cytoplasmic microvilli of cumulus cells pass through zona pellucida to the proximity of the oolema, where formation of gap junctions enables signalling and metabolic codependency. Oocytes produce factors affecting processes in cumulus cells, including their metabolism and viability. By modulating the abundance of cyclic nucleotides in oocytes, cumulus cells allow the maintenance of meiotic arrest, providing time for oocytes to finish their growth and gain competence for maturation. Because oocytes have a very limited ability to process glucose, metabolic cooperation with cumulus cells enables them to gain the energy needed for processes associated with growth and maturation. Several metabolic pathways of glucose processing create energy substrates for the formation of ATP, which they then transport to the oocytes. They also regulate the amount of lipid droplets in oocytes and protect them from cellular toxicity. An increase in the concentration of luteinizing hormone in the follicle just before ovulation induces the transmission of the signal for cumulus expansion. Interruption of the...
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Technologie výroby a kvalitativní parametry sýrů parmezánového typu
Karpsteinová, Sára
This bachelor thesis is dedicated to the topic: Production technology and quality parameters of parmesan type cheeses. The first part of the literature search deals with the general characteristics of Parmesan type cheeses. The second part describes the input raw materials, namely milk, rennet, milk cultures and salt. The next part of the thesis focuses on the technology of Parmesan cheese production. The individual steps of production include: preparation of the raw material, production of the curd, pressing and moulding, salting and maturation. This is followed by a section on European Union trademarks, which include: Protected Designation of Origin (PDO), Protected Geographical Indication (PGI) and Traditional Speciality Guaranteed (TSG). The next section describes the specific cheese-producing countries and the individual representatives of Parmesan type cheese. The cheese types are Grana Padano, Parmigiano Reggiano and Pecorino from Italy, Sbrinz from Switzerland, Džiugas from Lithuania and Gran Moravia from the Czech Republic. The last section deals with the sensory parameters of Gran Moravia Vecchio and Parmigiano Reggiano.
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Changes of selected indicators during the aging of beer
NOVÁK, Jan
The diploma thesis deals with the monitoring of selected quality parameters of chemical analysis during the beer maturation. The course of the change in alcohol content, the actual and apparent extract in the beer, the extract of the original wort and the degree of fermentation of the beer were monitored. Results of the analysis of beers from the Mini-Brewery of the Faculty of Agriculture of the University of South Bohemia in České Budějovice and the brewery Litovel, a.s. are compared in a uniform technological time of production at the end of maturation just before bottling with samples of beers purchased in the market network in the Czech Republic.
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Transcriptional activity of the genes characterizing developmentally competent cytoplasm in bovine oocytes.
Pešanová, Denisa ; Němcová, Lucie (advisor) ; Kalous, Jaroslav (referee)
4 Abstract The antral follicle provides a specialized microenvironment or niche, which is necessary for production of high quality oocyte. The developmental competence of bovine oocyte is influenced by the follicle size. Oocytes originated from medium or larger follicles (≥6 mm) have greater developmental competence (ability to develop to the blastocyst stage). The changes in cytoplasmic factors, for example mRNAs, could explain differences in oocyte developmental potential. Using Bovine Oligonucleotide microarrays the differences in gene expression profiles of oocytes at germinal vesicle and MII stages from medium (MF, 6-10 mm) or small (SF, 2-5 mm) follicles were characterized. The aim was to find differencies between oocytes diverse developmental competence. The expression fold change between the two experimental groups was in 61 genes. Subsets of 15 differentially expressed genes were validated by quantitative RT-PCR. Before maturation, significant differences were confirmed at the level of ATP5C1, MAP3K13, MTRF1L, TAF1A and UBL5. Subpopulations of oocytes were classified according to atresia of cumulus cells and follicle size. We determined the level of 12 individual transcripts after maturation. ATP5F1 remained stable in all experimental groups of oocytes. The level of BRD7 transcript remained stable...
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