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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.
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The Wine Market in the Czech Republic and the Politics of Wine
Vlašicová, Eliška ; Tomšík, Karel (advisor) ; Malý, Michal (referee)
The dissertation thesis is focusing on the wine market in the Czech Republic. The aim is to identify weaknesses in the wine sector in order to formulate recommendations for improving a current situation in the sector. The Common Agricultural Policy of the European Union and the Common Market Organisation for Wine was presented in the theoretical part of the thesis, where also theoretical aspects of a market including supply and demand were described, as well as an agri-food market and its specifics, wine commodity chain, determinants of demand, supply and prices of wine. In the following chapters an analysis of the wine market, especially with emphasis on the production potential of vineyards in the Czech Republic was created, and demand, supply and price of wine including a price transmission in the commodity chain of wine were modelled based on a regression analysis. The significant influence on demand of wine have had previous values of wine consumption and wine prices, substitutes consumptions (prices of substitutes were not a significant factors), household income and salary, a quality of the wine and awards in international competitions. Significant factors of the side of supply including the price of wine grapes, the price of wine, vineyard area, production of wine grapes, some aspects of weather and certain subsidies. A climate change, which is in progress, may result to the expansion of viticulture and winemaking in the Czech Republic and also to a change of varieties in vineyards. Demand has in the commodity chain of wine greater impact than the supply. It can have a negative effect on growers or winemakers. Planting of vines is not sufficient to maintain current levels of a production potential of vineyards in the Czech Republic. The ideal amount of annual planting vines should be about 655 ha. A related issue is financing a vineyards renewal, which is costly. Based on a financial analysis of small and medium-sized wine companies, it was found that these businesses cannot afford the renewal of vineyards from its own resources and will require grant assistance of the state, eventually EU.
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Freezing technology of bull sperm in relation to its survivability and fertilization ability
Doležalová, Martina ; Stádník, Luděk (advisor) ; Jiří, Jiří (referee)
The aim of optimalization the insemination doses production is to provide the highest fertilization ability of spermatozoa during the demanding proces of processing fresh semen and its subsequent cryopreservation. Temperature changes causes spermatozoa damage during the cooling and freezing. Spermatozoa is exposed to cold shock and many others limiting factors, which leads to cell death and therefore to decline of fertilization ability of thawed insemination doses. For increasing spermatozoa resistance, exactly the plasma membrane resistance against cold shock was fraction of egg yolk LDL cholesterol (low density lipoprotein) at various concentrations into the comercially produced diluents added. It is believed that LDL acts possitively to plasma membrane and helps to maintain the fertilization ability of spermatozoa after thawing. Following step in the proces of insemination doses production is slow cooling of diluted semen and equilibration, when the straws are store at cooling box for 30 minutes to 240 hours. This period is necessary to penetrate of certain diluent components into the spermatazoa also maintain the balance between their intracellular and extracellular concentration. Also important is subsequent freezing temperature gradient of insemination doses. The most suitable freezing method is based on computer controlled temperature decline in freezing chamber which allows the precise control of ice crystals formation that could tear and kill the cell.
During 2012 to 2016 was repeatedly collected semen from the group of breeding bulls (n = 27, Holstein and Czech Fleckvieh breed) at AI centre. Semen which fulfill the standard entrance conditions in first step was evenly into several parts divided. For dilution the three types of comercially diluents AndroMed, Bioxcell and Triladyl with and without LDL addition were used. Into the diluents AndroMed and Bioxcell the concentration of LDL 4 %, 6 % and 8% into the dilent Triladyl 6 %, 8 % and 10 % was added. Diluted semen was filled into the glass capillares with volume 0,1 ml and temperature +4 °C. Subsequently the sample was placed to cold bath (0°C) for 10 minutes. Then the volume of capillare with physiological solution (37 °C) was mixed and for next 120 minutes was incubate. The effect of cold shock to proportion of live spermatozoa was evaluated by using Eosin and Nigrosine staining technique during heat test of spermatozoa survivability after spermatozoa heating and after 120 minutes of incubation.
The more suitable semen diluents which provide the higher spermatozoa resistance against cold shock were AndroMed and Bioxcell. Together the possitive effect of LDL addition into the diluents to lower decrease of proportion of live spermatozoa during heat test was found (P<0.05). The most suitable LDL concentration which had a favorable influence at spermatozoa resistance against cold shock was 6 % in diluent Bioxcell. Values of the proportion of live sperm were higher at the beginning of the heat test (+1.31% to + 3.2%) and after 120 minute incubation (+5.82% to +8.41%) compared to other diluents with and without addition of LDL.
In the next step the process of equilibration was optimized, is an important part of insemination doses production. The effect of the length of equilibration for subsequent fertilization ability of spermatozoa was evaluated using spermatozoa motility based of CASA and proportion of live spermatozoa after thawing and during heat survival test lasting 120 minutes (37 ° C). Suitable semen was diluted by comercially used diluent AndroMed based on soya lecithin, filled into the straws (0.25 ml), cooled and equilibrated in cooling box for 30, 120 and 240 minutes and freezed in programmable freezing box applying four types of freezing curves differing in temperature rate decline. There was used standard and by producer recommended 3. phase freezing curve, then 2. phase freezing curve, and 3. phase freezing curve with slower as well as rapid decline of temperature rate in freezing chamber, compared with standard freezing curve. The highest spermatozoa motility was found using 240 minutes of equilibration by +2.72% and +4.58% compared to other lengths of equilibration (P <0.05 to 0.01). The highest proportion of live spermatozoa was found using 120 minutes of equilibration (+6.87 % and +8.68 %). The highest average spermatozoa motility during heat test after thawing was achieved by using 2. phase freezing curve (from +2.97% to +10.37%, P <0.05), also in the proportion of live spermatozoa (from + 4.37% to +8.82%, P <0.01). When evaluating interaction between the length of equilibration and freezing curve (standard 3. phase and 2 . phase freezing curve), the highest average spermatozoa motility and proportion of live spermatozoa using 240 minutes of equilibration by both freezing curves was reached, there was no statistically significant differences. As well as, in all evaluated parts of this study the individual differences between ejaculate of bulls and within semen from one bull (P <0.05) as secondary effect were found.
To maintain good fertilization ability of semen during cryopreservation is necessary to increase the spermatozoa resistance against cold shock using addition of correct concentration of LDL into the commercially used diluents AndroMed and Bioxcell. Subsequently the fertilization ability of insemination dose is influenced by cooling, the length of equilibration and freezing. The length of equilibration 120 minutes and more as well as gentle way of freezing according to freezing curve, which ensures a gradual decrease of temperature in freezing chamber provided the higher average spermatozoa motility and proportion of live spermatozoa.
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Point to Line Mappings and Other Line Parameterizations not only for Hough Transform
Havel, Jiří ; Kälviäinen, Heikki (referee) ; Lefevre, Sebastien (referee) ; Herout, Adam (advisor)
Tato práce se zabývá Houghovou transformací (HT). HT je nejčastěji používána pro detekci přímek nebo křivek, ale byla zobecněna i pro detekci libovolných tvarů. Hlavní téma této práce jsou parametrizace přímek, speciálně PTLM - zobrazení bodů na přímky. Tyto parametrizace mají tu vlastnost, že bodům v obrázku odpovídají přímky v parametrickém prostoru. Tato práce poskytuje důkazy některých vlastností PTLM. Za zmínku stojí existence páru PTLM vhodného pro detekci a efekt konvoluce v obrázku na obsah parametrického prostoru. V práci jsou prezentovány dvě implementace HT. Obě využívají k akceleraci grafický hardware. Jedna využívá GPGPU API CUDA a druhá zobrazovací API OpenGL. Jako aplikace detekce přímek je uvedena část detekce šachovnicových markerů použitelných pro rozšířenou realitu.
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Location-aware data transfers scheduling for distributed virtual walkthrough applications.
Přibyl, Jaroslav ; Sochor, Jiří (referee) ; Sojka, Eduard (referee) ; Zemčík, Pavel (advisor)
Důležitou součástí aplikací procházení distribuovanou virtuální scénou je proces plánování přenosu dat. Jeho hlavním úkolem je zajištění efektivního přenosu dat a maximální kvality renderovaného obrazu. Největší vliv na kvalitu renderované scény mají omezení síťového připojení. Tyto omezení lze redukovat pomocí multi-resolution reprezentace dat scény, určováním priorit stahování jednotlivých částí scény, a přednačítáním dat. Pokročilé metody pro určování priorit a přednačítání částí scény jsou založeny na predikci pohybu uživatele vycházející z matematického popisu jeho pohybu. Tyto metody jsou schopny predikovat následující pozici uživatele jen v krátké vzdálenosti od jeho aktuální polohy. V případě náhlých, ale pravidelných změn směru pohybu uživatele jsou tyto metody nedostatečné co do přesnosti i délky predikce. V této práci je navrhnut komplexní přístup k řešení plánování přenosu dat splňující i tyto požadavky. Navrhované řešení využívá predikci pohybu uživatele založenou na znalostech k určení priority stahování dat i předstahování částí scény. Provedené experimenty nad testovacími daty ukazují, že navržené schéma plánování přenosu dat umožňuje dosažení vyšší efektivity přenosu dat a vyšší kvality renderovaného obrazu během průchodu testovací scénou.
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Digital Repository in Practice - More Than Just a Data Storage
Andrejčíková, Naděžda
Research generates ever more data. For guidance in these data a digital repository of published results of science and research should serve as well as a digital repository containing these scientific data. Metadata are very important in this process. They can link related data from completely different external sources. In our paper, we focus on the use of external resources in building institutional repositories.
Slides: idr-1036_1 -  PDF; idr-1036_2 - PDF
Video: idr-1036_3 -  MP4
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Personal income taxation from employment, self-employment and rental income in 2014
HOUFOVÁ, Petra
The aim of my diploma thesis is to analyze the principles of personal income taxation including social contributions and health insurance. Overall personal income tax is composed of five different partial tax bases. The first partial tax base consists of income from employment, the second one is self employed income, the third is income from rental property, the fourth is income from capital and the last is "other income". This thesis will deal with the first four partial tax bases. In the theoretical section I have described the most important concepts of personal income tax structure, social contribution and health insurance. The practical part is divided into four chapters according to partial tax base. I have chosen six different amounts from 100 000 CZK to 5 000 000 CZK which were used for tax calculation. The main goal is to compare partial tax bases of personal income tax in 2014.
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Cultural Centres
Adolfová, Barbora ; PROKOP, Petr (advisor) ; KAŠPAR, David (referee)
This thesis is concentrated on cultural centres built between years 1960 and 1990 in the former socialist Czechoslovakia. Six cultural centres have been chosen and analyzed to conclude the purposes they serve as well as the programs they offer. These chosen cultural centres are run as municipal organisations financed from the town budgets. The six towns where they are located are similar to each other in terms of their history, size and the time when their cultural centres were built. All of these centres share difficulties with the lack of cultural interest of local citizens, bad technical shape of the buildings in question and low budget.
The aim of this thesis is to compare the functioning of these six cultural centres and conclude whether being directly funded and influenced by the municipal councils has a positive impact and should serve as a model for cultural centres or should be replaced by a different one. It also focuses on cooperation between the management of cultural centres and municipal officials, cooperation with other local cultural institutions and cultural centres from different towns.
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Characteristics of the working behavior of Czechs and Ukrainians
BYKOVA, Sofia
The aim of this work is to create a transparent and comparable characteristics of the work behavior phenomenon within the cultures of those states - what is common and what is different between them, or maybe incompatible .It is supposed to have some analysis of possible conflicts and their connection with the mentality. The primary reason of this aim choosing is the specialty I study. My work contains information that could be interesting and useful not only for me and my future job, but also for managers and other employees. Overview of examined issues contains specific points, such as the fundamentals of economic psychology and behavioral economics (symbiosis of psychological and economic opinion on motivation and rationality of individuals), theories of motivation and reaction to different occurrence, characteristic of the term "mentality", general points about the human impact of the world economy. For realizing the goals of my work the following hypotheses have been proposed - Czech and Ukrainian mentality have significant differences, though these cultures are close. - Ukrainian and Czech employees are able to work effectively in a team and find a "common language" in the workplace. The difference in mentality does not obstruct on it. - Employers could be interested in the Ukrainian employees taking into account their high concernment and motivation. All three of the hypotheses were confirmed by observed data and comparison of mentality characteristics. Czechs are often tolerant to other cultures, moreover Ukrainian culture is not much different and does not create difficulties in the working relationship. Based on the fact that the chosen company has no conflicts associated with work behavior and differences in mentality, it's hard to define my contribution to this organization work.
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