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Determination of Total Antioxidant Capacity in Select Food products and Dietary Supplements by Flow Injection Analysis with Chemiluminiscent Detection
Průchová, Karolína ; Rychlovský, Petr (advisor) ; Hraníček, Jakub (referee)
In this diploma thesis, a functional method for the determination of total antioxidant capacity by flow injection analysis with the chemiluminiscent detection was successfully developed. Luminol in carbonate buffer (composed of Na2CO3, NaHCO3 and (NH4)2CO3), with Cu2+ ionts as a catalyst, was used as a chemiluminiscent reagent. Chemiluminiscent radiation was induced by a diluted solution of hydrogen peroxide, a long-lasting chemiluminiscence was observed. First part of this thesis is dedicated to the optimalisation of the experimantal conditions for antioxidant capacity measurements as well as to the construction of apparatus for flow measurings. L-ascorbic acid was used as a standard. In the second part of this thesis the freshly developed method was used to determinate total antioxidant capacity of real food product simples, namely tea and coffee simples, beers, wines, chocolates, fresh fruit juices and selected food supplements. Results of this analysis were expressed as a vitamin C equivalent antioxidant capacity (VCEAC) related to standard, in mg/ml for liquid simples and in g/mg for solid simples. Results obtained are: tea simples 53 - 347 mg/1g of dried product, coffee simples 399-449 mg/g of dried product, beers 1,1-1,4 mg/ml, wines 4,2 - 4,8 mg/ml, fresh lemon juice 4,7 mg/ml, fresh kiwi juice 2,1...

Men's awareness about the issue of testicular cancer.
POSPÍŠILOVÁ, Markéta
Theoretical solution Testicles are the primary male sexual organs producing testosterone. They not only make sperm but also secondary sexual features and the whole personality. We should mainly pay attention to testes in oncology because there are more occurrences of tumors with the men of younger age. These men might be very sensitive about the problems concerning sexual system and that is why the bachelor thesis deals with the issues of men's knowledge of testicular cancer. There is basic information in the thesis about organs anatomy, factor of disease, diagnostics and medical treatment. The thesis is further focused on secondary preventive measures and method of self-examination of testicles. It helps to recognize the problem in time which is in this kind of cancer very crucial. There is also mentioned the role of nurses and their instruction to men about the prevention of testicular cancer, medical care of the patient during the diagnostics, pre-operative preparation, postoperative care and other healing process. Aim of the Thesis Aim 1 Find out how much men are aware in the field of testicular cancer? Aim 2 Find out the change of behavior of men to their health after the operation of testicles? Research Question n. 1 How much men are aware about the problem in their risk age? Question n. 2 How much men are aware of self-examination methods? Question n. 3 In what field has changed the men's behavior to their health after the operation of testicles? Methodology To be able to find out necessary data, qualitative method was picked. To the collection of information was used method of half-standard interview with the questions to the concrete issues. Five respondents in a risk age were approached to the research in the case of malignant tumors origin on testicles and five respondents who had already undergone the treatment of this disease. Information was analyzed, consequently put to the categories and finally evaluated. Results Results of the research showed that men are mostly aware of the problems of testicular cancer. They usually underestimate this disease because they are not informed about the issue enough. Men usually know about the symptoms but most of them have wrong idea about the age occurrence and medical treatment. Preventive method of self-examination is for men usually unknown. Respondents who underwent operation of malignant tumor of testicles are about this method properly instructed. Frequently, according to the results, they make light the return of the disease and also do not practice the self-examination method regularly. Results also revealed that this disease is still somehow a taboo. Some respondents with the successful cure admitted that they were ashamed for this diagnoses. Conclusion The research showed us that men are not informed enough about the malignant tumor of testicles. This also confirms the fact that healthy men do not know the self-examination method. According to the results men who underwent the treatment of testicular cancer are now more informed but they usually underestimate the necessity to do the self-examination regularly. They also admitted in the interview that they were not informed enough before the disease. If they were, their health problem could have been discovered earlier and the high risk of metastasis could have been lower. For all this there is a need to increase the knowledge of the malignant testicle tumors in population which will influence the regular usage of self-examination method and it can also change the attitude of men to their health. Bachelor thesis contains pamphlet about the origin of testicular cancer. It is intended for men who are in risk age and it will be offered as a practical usage in medical facility.

Sorption and Stabilization of Metals/Mettalloids by Innovative Synthesized Sorbent Amochar.
Ouředníček, P. ; Trakal, L. ; Komárek, M. ; Pohořelý, Michael
Remediation of contaminated soil which is based on stabilization and immobilization of potential\nhazardous substance by sorption materials has been studied intensively nowadays. Biochar – activated organic carbon belongs to this group of stabilizing agents which can adsorb wide range of contaminants, including metals/metalloids. Surface area of the biochars is quite large in general and functional groups (e.g. COO–) can form chelates or alkaline elements on the surface, which is represented by cation exchange capacity. Altogether with the high pH values (7.00 – 10.00), biochars are quite effective sorbents and can adsorb metals/metalloids from the solution (ground water), especially in acidic soils (in the environments affected by intensive mining activities). Sorption\neffectiveness can be increased (especially for As (V) or Cr (VI) sorption) by modification of biochar by various types of secondary oxides. Innovative sorbent AMOchar (AMO + biochar) has been synthesized currently. The product was prepared by adding of biochar to the reaction solution during amorphous manganese oxide (AMO) synthesis. The AMOchar was formed mainly by Mn-oxalates which had coated surface of the pristine biochar. AMOchar composite was able to remove significantly higher amounts of various metal(loid)s from the solution despite the rather high pH of the material. Sorption effectiveness was high not only in case of Pb (II) sorption (almost 99%), and Cd(II) (51.2%), but also a very high amount of As(V), 91.4%. Additionally, both AMOchar composite was able to reduce Mn leaching. This can avoid potential post-contamination caused by the dissolution of less stable Mn-oxalates as observed in the pure AMO.
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Arctic tundra dendrochronology
Lehejček, Jiří ; Svoboda, Miroslav (advisor) ; Monika, Monika (referee)
Historically unprecedented environmental change in the Arctic ecosystems is often given into the context of its past and possible future development. In the region where instrumental meteorological observations are scarce archives need to be investigated in order to address this issues. The comprehensive synthesis one of the archives: long-live circumpolar evergreen Juniperus communis L. shrub is presented here. 20 individuals from southwest Greenland were investigated at the cell anatomy level to understand the ecology of the species and unhide its potential for environmental and climate reconstructions. The findings are as follows: i) Stop of exponential cross-sectional conduit-lumen widening with increasing age is in contrast with conduit-lumen nature of trees. This indicates that shrubs do not need to saturate their water and nutrient demands via traits of classical hydraulic conductivity law but rather developed different mechanisms. Extreme weather conditions result in prostrate growth form. However, different weather factors probably influence shrub growth differently: While snow and wind act mechanically (a), temperature influences the form of growth physiologically (b). a) So long as the young shrub stem has high resilience to bend back to an upright position after snow melt and so long as it can withstand the wind during the vegetation season it most likely grows upright and the conduit-lumens widen. b) Temperature, resp. freeze-thaw events are responsible for the shrubs preference of safety (finite size of conduit-lumens) over hydraulic efficiency, thus not allowing for more primary growth. All of these (and other) factors are apparently working together and the transition of vertical to more horizontal growth is gradual. As a consequence, the conduit-lumen sizes may not have to be further increased (due to ecophysiological restrictions possibly also must not) because water is no longer transported against gravity. ii) Observed age/growth trend has to be taken into consideration for further employment of the wood anatomical parameter in paleoenvironmental studies. That is, shrub cell parameters can only be used for this purposes if correctly detrended. This allows for more accurate as well as longer reconstructions because youth trend was often neglected in reconstructions based on shrub annual-rings. iii) The south-western Greenland Ice-Sheet (GrIS) melt rates reconstruction is presented for the whole 20th century. This part of GrIS is considered as the most active. According to the presented reconstruction current GrIS melt rates are not uncommon for the last century being comparable to first decades of 20th century. This finding is particularly important contribution to the debate on Atlantic meridional overturning circulation (AMOC). Too high fresh water inputs into the Northern Atlantic from GrIS melting may slow down or even stop the AMOC which would result in more continental climate in Europe. Presented results indicate that this threshold lies higher than observed current melt rates of GrIS. Fascinating Juniperus comunnis species has shown to be able to address many ecological as well as environmental open questions and due to its longevity and abundant distribution has a great potential to become an important player in the Arctic research.

Information content in vocalization of guinea pigs (Cavia porcellus): individual distinction and recognition of predators
Baklová, Aneta ; Baranyiová, Eva (advisor) ; František, František (referee)
Guinea pigs represent domesticated precocious rodents which became common pets. From the first day after birth they are fully vocal. This thesis was devoted to the vocalization of pups. The aim of the thesis was to 1) determine the age when the vocal individuality in whistle sound is demonstrable; 2) test possible ultrasonic signals emitted by young guinea pigs; 3) study the antipredator reactions and alarm calls to aerial (bird of prey) and terrestrial (dog) predators and human (control test). A total of 16 guinea pig pups were tested for vocal individuality, 28 pups for ultrasonic vocalization and 27 adolescents for predator recognition. When testing vocal ontogeny during the first 9 days after birth, I observed changes in temporal, frequency and parameter of intensity . When I test vocal individuality by cross-validated discriminant function analysis (DFA) based on ten acoustic parameters, calls were classified to correct animals with following success: day 1 = 71.9%, day 3 = 58.8%, day 5 = 53.10%, day 7 = 50.60% and day 9 = 63.10%. The highest frequency in whistle was 30.03 kHz. In predator discrimination reactions as freezing, fleeing and vigilance were observed. In the presence of dog, guinea pigs reacted for the longest time and most frequently by freezing. When confronted with a bird of prey, I observed for a longest time and most often fleeing and then freezing. When exposed to a human, guinea pigs showed mostly vigilance. Almost no vocalization was observed except for two events of alarm calls - drrr as in the presence of dog and chirrup as reaction to bird of prey. The following conclusions can be drawn from the presented results: 1) vocal individuality of guinea pigs is demonstrable immediately after birth and the rate of individually different vocal parameters changes with age; 2) guinea pigs are able to produce sound up to 30 kHz, i.e. within the ultrasound range, but signals of high frequencies are not crucial for their communication; 3) guinea pigs discriminate between terrestrial and aerial predators, but they emit alarm calls rather rarely.

Influence of meadow management on the migration behavior of selected species of butterflies
Bubová, Terezie ; Langrová, Iva (advisor) ; Farkač, Jan (referee)
Migrations are the key process and one of the basic biological features, which allow survival of endangered species in fragmented landscape. In the last decades, agriculture intensification, industry and urbanization caused that number of natural butterfly habitats has significantly decreased. The localities originally suitable for butterflies are currnetly converted to farmland or building plots. This PhD thesis aimed to find a compromise solution of meadow management, which should allow a commercial use and concurrently do not jeopardize the continued existence of endangered or threatened species. The main idea of this study was in the intentional emigration causing in the middle of flight period, which should lead into resettlement of the population to another (potentially more suitable) locality. Possibility of aimed manipulation with butterfly emigrations would be considered as a major breakthrough in their protection. The investigated species Phengaris nausithous (Bergsträsser, 1779) and Phengaris teleius (Bergsträsser, 1779) are both considered to be flagship species for protection of European butterflies at open meadows. This study is based on research, which was carried out in 2013-2015 at 17 patch in localities Dolní Labe, Czech Republic. In above mentioned years, one selected meadow was mowed in the middle of flight season and the emigrations were then monitored using mark-release-recapture method. Results of population and migration characteristics were calculated in MARK 8.1 software. Subsequently, the effect of mowing on emigration (comparison of emigrations from the meadow before and after mowing) was evaluated using Statistica 13. The hypotheses of this study were based on the assumption, that the loss of resources after well-timed mowing should increase the activity of adult butterflies. During the monitoring, number of emigrations was increased only in flight season 2015. Unfortunately, the statistical evaluation did not show significant effect of mowing on migrations. On the other hand, the hypothesis dealing with colonization of nearest meadows was confirmed. Effect of intentional emigration caused by management interventions was unfortunately not proved. However, we found out, that even though the population at one mowed meadow decreased clearly, the metapopulation size at the locality remained more or less stable. At investigated (mowed) meadow, there was observed a sharp decline of P. nausithous abundance. On the other hand, P. teleius population was only slightly reduced. It is therefore conceivable, that P. teleius are not as susceptible to innapropriate term of mowing. The results obtained in our research conclusively displayed no possible positive effect of mowing in the middle of flight season and a necessity of suitable management maintenance at localities inhabited by Phengaris butterflies.

Playing as a means of increasing motivation in teaching vocational subjects
Kolmanová, Linda ; Hanušová, Marie (advisor) ; Drahomíra, Drahomíra (referee)
Bachelor thesis called A play as a means of improving motivation in teaching vocational subjects, is used for the needs of their insight into the problems of motivation in school and its improvement through the activation methods specifically games. The theoretical part brings basic concepts that relate to the themes of the motivation in school and activation methods in education, which are the basis for the development of the practical part. In the practical part is through the observation and the final test in the learning block validated the proposed board game of economic, as the activation method for increasing the motivation of the economic sector. Last but not least, the results are presented and carried out.

Corrosion behavior of plasma coatings CuAl10 and CuAl50 on magnesium alloy AZ 91
Kubatík, Tomáš František ; Stoulil, J. ; Stehlíková, K. ; Slepička, P. ; Janata, Marek
The most common magnesium alloy AZ 91 is widely used as a structural material, but its use is limited at higher temperatures and high humidity. Plasma spraying is a technology that allows to prepare protective metallic and non-metallic coatings on a wide variety of substrates including magnesium and its alloys. In this study, CuAl10 and CuAl50 were plasma sprayed on magnesium alloy AZ 91 with the aim to study corrosion resistance of the plasma sprayed coatings. The corrosion resistance of layers was evaluated by the method of electrochemical potentiodynamic measurement as well as long-term corrosion tests in a condensation chamber with 0.5 mol\nNaCl at the temperature of 35 °C for 1344 hours. Layers with 1, 2, 5 passes and passes of CuAl10 with the thickness ranging from 75 to 716 mm and CuAl50 with the thickness ranging from 64 to 566 mm were prepared. The increased corrosion velocity was observed in the case of thin layers of 2 and 5 passes due to the development of a galvanic corrosion couple. The CuAl10 layer prepared with ten passes has an outstanding corrosion resistance.

Possibilities in monitoring of laser welding process
Horník, Petr ; Mrňa, Libor
With increasing demands on the quality of the welds, it is usual to apply automated machine welding with monitoring of the welding process. The resulting quality of the weld is largely affected by the behavior of keyhole. However, its direct observation during the welding process is practically impossible and it is necessary to use indirect methods. At ISI we develop optical methods of monitoring the process based on analysis of radiation of laser-induced plasma using Fourier and autocorrelation analysis. Observation of keyhole inlet opening is partially possible through a coaxial camera mounted on the welding head and the subsequent image processing. A high-speed rear camera to understand the dynamics of the plasma plume. Through optical spectroscopy of the plume, we can study the excitation of elements in a material. Shielding gas flow can be visualized using schlieren method.

Multimedia Data Processing in Heterogeneous Distributed Environment
Kajan, Rudolf ; Ferko,, Andrej (referee) ; Míkovec, Zdeněk (referee) ; Herout, Adam (advisor)
Pervasive computing sa zameriava odstránenie zložitostí pri interakcii s výpočtovou technikou a zvýšenie efektivity pri jej každodennom používaní. Ale i po viac ako 15 rokoch od sformulovania hlavných cieľov Pervasive computingu existujú aspekty interakcie ktoré stále nie sú súčasťou užívateľskej skúsenosti s dnešnou technológiou. Bezproblémová integrácia s prostredím vedúca k technologickej neviditeľnosti, alebo interakcia naprieč rôznymi zariadeniami predstavujú stále veľkú výzvu. Hlavným cieľom tejto práce je prispieť k tomu, aby sa ciele Pervasive computingu priblížili k realizovaniu tým, že predstavíme spôsob intuitívneho zdieľania informácií medzi osobným a verejne umiestneným zariadením. Predstavili sme tri interakčné techniky, ktoré podporujú intuitívnu výmenu obsahu medzi osobným zariadením a zdieľaným displejom. Tieto techniky sú založené na prenose videa, rozšírenej realite a analýze pohľadových dát. Okrem interakčných techník sme tiež predstavili mechanizmus pre získavanie, prenos a rekonštrukciu aplikačného stavu na cieľovom zariadení.