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Influence of Storage Conditions on Metabolic Profile of Apples
Duroňová, Kateřina ; Vávrová, Milada (referee) ; Kráčmar, Stanislav (referee) ; Márová, Ivana (advisor)
The goal of presented dissertation has been complex analysis of changes in content of fatty acids, enzymatic and low-molecular antioxidants in apples and related evaluation of perception of originators of storage diseases for apples stored in various conditions. Main part of the work has been dedicated to study of the impact of storage of apples in modified atmosphere with reduced amount of oxygen and in reference “normal” atmosphere for six months. Next part of the work has been dedicated to study how apple storage in common, consumer affordable, conditions (storage in a cellar, in a refrigerator, and in room temperature) affects content of low-molecular antioxidants. For testing has been selected apple kinds Jonagored, Golden Delicious, Idared, Šampion, and Granny Smith. Within the scope of this work has been optimized the method for determination of fatty acids in plant material with higher content of wax. The measured values imply the apples are valuable source of many important nutrition substances like vitamins, provitamins and antioxidants. During the storage process these substances exhibit considerable protective function. Long-term storage, mainly in the atmosphere with reduced amount of oxygen (FAN), enables preservation of majority of these important nutrition substances depending on the kind of apple and conditions of storage. Freezing process is conservative to apples (mainly in the presence of protective substances), while in the process of drying the values of all monitored antioxidants decrease depending on temperature and conditions of drying. Upon the choice of the storage method one must consider nutrition, sensoric characteristic and consumer demands.
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Freezing
Ševčík, Andrej ; Chrobák, Ondřej (referee) ; Kvíčala, Petr (advisor)
The subject of diploma thesis is cycle of paintings, animation and video. This work is based on the operation system error. I focusing on well know phenomen of freezing computer and follow layering of system windows over themselves. Due to an error may arise aesthetic shape, which may refer to geometric abstraction. On this phenomenon interested me especially the elementary aspects of painting, building space on surface, geometry, movement and shape.
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Changes in selected local fruits during freezing.
Matějková, Markéta ; Melounová, Jitka (referee) ; Márová, Ivana (advisor)
This diploma thesis was focused on study of low-molecular antioxidants present in various kinds of fruits, namely berries. In theoretical part detailed characterization of antioxidants studied in presented work and their biological effects are introduced. Further, principals of processing and storage of specified species of fruits are discussed. Changes observed during storage of specific fruits are described too. In practical part changes in content of selected antioxidants in berries were followed. As studied material strawberries, raspberries, blueberries, red and black currants were used. All kind of these fruits was stored in fridge for six months using several different kind of processing. Berries were stored as whole fruits, whole osmotically processed fruits by sucrose, raw pulp and sweetened pulp. At first, starting values of selected antioxidant parameters were measured in fresh fruits (ascorbate, total antioxidant activity, total phenolics, catechins and individual flavonoids). After freezing the same parameters were measured regularly in two month periods. As the most suitable method of fruit processing, with regard to antioxidant content, storage of the whole fruits or pulp can be recommended. Content of ascorbate decreased in all forms and species of the processed fruits during all the time of storage. Oppositely, the content of other studied antioxidants exhibited fluctuations or increasing trend. Sensory analysis was proved for the whole fruits and also for whole sweetened fruits.
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Changes of enzyme activities in fruits during long-term storage
Ferdová, Jitka ; Melounová,, Jitka (referee) ; Márová, Ivana (advisor)
This study is focused on study of changes of enzyme and low-molecular weight antioxidants in different fruits during long-term storage. In theoretical part individual low-molecular weight antioxidants and enzymes are described. The main causes of fruit decay and some possibilities of fruit preservation and storage are summarized. As biological material some common fruits were chosen - green and red apples, peaches, plums and white grapes. The fruits were stored in laboratory, cellar, in refrigerator and in freezer. In freezing experiments some ways of fruit preparation and processing were tested and their influence on fruit antioxidant status was compared. Shortened storage experiment was applied on blueberries, cranberries, raspberries and strawberries too. In fruits some group parameters – total antioxidant status, dry mass content, ascorbate level, total flavonoids and total phenolics were analyzed spectrophotometrically. Individual flavonoids and phenolics were determined by RP-HPLC/UV-VIS and on-line LC/PDA/ESI-MS. Antioxidant enzyme activities (superoxide dismutase SOD, catalase CAT, polyphenol oxidase PPO and lipoxygenase LOX) were measured by spectrophotometry. The surface microscopy and cultivation of moulds from fruit surface were performed too. Influence of storage conditions on biological activities is dependent on fruit sort. Freezing is the most suitable procedure for long-term storage without significant changes of active substance content. Long-term storage in controlled temperature conditions and/or atmosphere is usable for fruits with longer storage period. In these fruits stabile levels of antioxidant enzymes are stored for relatively long time. Some of enzymes act synergistically. Enzyme activities differed according to storage phase; at the beginning mainly high SOD and LOX activities were observed. CAT and PPO are probably activated as defence systems in rippened and/or damaged fruits. Levels of total as well as individual low molecular weight antioxidants varied during storage in all sorts, generally, increased course with longer storage period can be observed.
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Low Temperature and Cryogenic Treatment of Casehardened Parts
Bílková, Lenka ; Juliš, Martin (referee) ; Kouřil, Miloslav (advisor)
This work deals with the assessment of the influence of low-temperature treatment on the structure and properties of casehardened surface layer of parts. The objective was to assess whether low-temperature treatment is sufficient, insufficient, or unnecessary for the given purpose. Gears which form a part of Zetor tractors gear boxes were used as samples. Thirteen pairs of frozen and non-frozen samples were used; they were taken from production batches throughout 2007, their hardness was assessed and furthermore, the experiment itself, freezing casehardened and hardened samples to different temperatures reaching as low as -196°C, was carried out. A moderate increase in hardness was registered with the majority of the frozen samples, which proved the effectiveness of the low-temperature treatment.
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Vliv nízké teploty na propustnost buněčných membrán a přežití rostlin
Kubovčíková, Anna
Plants are naturally exposed to low temperatures in nature. During the winter, the temperatures are the lowest and in certain places they even reach very low values. Jasmonic acid plays an important role in the plant's resistance to low temperatures. In the thesis, we have focused on the effect of the PLIP genes that produce precursors of jasmonic acid. The role of the genes in cold resistance in Arabidopsis thaliana was studied after acclimation in different light conditions. The observed parameters in plants acclimated to low temperatures were the parameters of photosynthesis, intactness of cell membranes and survival after exposure to freezing. The results of the experiments proved that the mutation of the PLIP genes cause a decrease in the integrity of the cell membranes when exposed to freezing, and conversely, the ectopically increased expression of the PLIP3 gene results in an increase in plant resistance. Based on ion leakage, we determined LT50 values for each variant, and it was shown that the difference between the most resistant transgenic line plip3 ox and the mutant line in all three PLIP genes is more than 4 °C. Subsequently, a plant survival test after freezing was performed, where it was demonstrated that the LT50 value correlated with plant survival. Chlorophyll fluorescence analysis showed that after acclimation to low temperature, there are no large differences in photosynthetic parameters between individual genotypes with modified PLIP level. The light that was applicated during acclimation had a more pronounced effect on the plants. Plants acclimated at low intensity showed higher values of non-photochemical quenching as well as greater maximum quantum yield of photosystem II. The results prove that the PLIP genes are significantly involved in the resistance of plants to low temperatures.
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Insects freezing into ice
KALÁT, Matěj
The bachelor thesis deals with the topic of insects freezing into ice. The literature research includes the history of cold tolerance in insects and their strategies in defending against freezing. The second part of the thesis discusses the results of tests of aquatic arthropods freezing into ice and their survival rates after freezing.
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The influence of rhytmical movemet on patients with Parkinson's disease
MYSLIVCOVÁ, Anna
This bachelor thesis deals with the issue of a progressive neurological disease called Morbus Parkinson, which is translated to Czech as Parkinson's disease. This disease irreversibly damages the central nervous system and cannot be cured yet. It is only possible to alleviate the symptoms by pharmacological treatment and improve the quality of life of the patients with the help of rehabilitation. The aim of the work is to describe the main issues of the disease, to clarify the possibilities of physiotherapy and to design a rhythmic exercise unit on the basis of which educational videos for home exercise of patients with Parkinson's disease were created. The first part summarizes general knowledge about Parkinson's disease, history, development and rehabilitation. Most of the work deals with the research itself, which was attended by 3 clients with Parkinson's disease. The individual case reports consist of an initial entrance examination, which also includes, for example, tests evaluating stability and gait. This is followed by two months, during which the exercises took place once a week and then the current state was compared with the results of the initial examination. The studies found and the subjective evaluation of probands show that it is appropriate to include rhythmic exercises in the rehabilitation. Due to the state of emergency lasting continuously from 5th October 2020, it was not possible to conduct group exercises, so the exercises were conducted with two patients online, which allowed patients to exercise safely at home and were not at risk of infection. One patient underwent exercises normally after loosening of the regulations issued by the government. The work can serve as a source of information for the lay and professional public and methods of solution can be used in physiotherapeutic practice.
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Účinnost vybraných postupů konzervace ryb na zachování morfometrických ukazatelů
VOGALOVÁ, Pavlína
This bachelor's thesis is focused on the topic of fish fixation and preservation. Experiments regarding various preservation methods are covered in many scientific ichthyological texts. Unfortunately, most of these works are exploring only one preservation method, so mostly there isn't the possibility of comparison with different methods using the same species. Aim of this work is introduction to preservation and fixation methods, that affect morphometric parameters of fish. Theoretical part of this thesis are procedures of fixation and preservation. The experiment itself is focusing on effect of preservation over time. Selected morphometric parameters were observed and measured in selected fish species to discover potential changes in these parameters. Measurements were being taken every two weeks for few months.
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Ecological differences between herbs and woody plants, and evolution of the herbaceous habit
Klimeš, Adam ; Herben, Tomáš (advisor) ; Lens, Frederic (referee) ; Těšitel, Jakub (referee)
Ecological differences between herbs and woody plants, and evolution of the herbaceous habit Adam Klimeš, doctoral thesis Abstract Flowering plants (angiosperms), which make up most present-day vegetation, were originally woody. While flowering plants have repeatedly given rise to herbaceous lineages since their first appearance, we lack a clear explanation for these common evolutionary events. Freezing temperatures and drought periods have been proposed as factors which had caused huge success of the younger growth form but the evidence is very limited and not in favour of these hypotheses. In this thesis, we aimed to build the foundations of research on the evolution of herbs. We outlined new potential drivers of the evolution of herbs, suggested solutions to some methodological challenges and provided evidence about differences between herbs and woody plants relevant to the hypotheses on herb evolution. To this end, we used common garden experiments with young plants of both growth forms and global trait data from public databases which we evaluated using phylogenetic comparative techniques. Annuality of aboveground biomass and fast life-strategy of herbs are characteristics which differentiate them from woody plants and which in some conditions are expected to be behind their success. Apart from the...
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