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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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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.
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Antioxidant, anti-proliferative and immunomodulatory effect of fruits, vegetables and mushrooms in vitro
Doskočil, Ivo ; Havlík, Jaroslav (advisor) ; Orsák, Matyáš (referee)
Recently there has been an increasing interest in discovering of new species of plants and mushrooms which have antioxidant or anti proliferative activity. The interest is caused by the fact that these species have medicinal and food utilization. These properties of plants and mushrooms can be used when dealing with many diseases which may be connected with oxidative stress (inflammatory bowel disease, cardiovascular disease, hypertension, and tumour disease, etc.).
The thesis propounds characteristics of in vitro antioxidant and anti proliferative activity of 19 types of juices and 28 methanol extracts of fruits and vegetables, which are common parts of a diet. In the thesis there are also characteristics of 13 ethanol extracts of edible mushrooms of the order of Polypore (Popyporales). Antioxidant activity was quantifie by 2, 2 diphenyl 1 picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), and inhibition of nitric oxide (NO) production. Cytotoxicity was measured by MTT (3 (4,5 dimethylthiazol 2 yl) 2,5 diphenyltetrazolium bromide. Immunomodulatory activity was determined by an assay of phagocytic activity of human neutrophil granulocytes. Further a total phenolic content (TPC) and total beta glucan content were investigated; these are considered to be the potentially active constituents participating in mentioned activities.
From the obtained results it is evident that juices (TPC = 1603.2 mg GAE/L; ORAC = 438.5 umol TE/g)
and a bilberry (Vaccinium myrtillus) fruit extract (ORAC 836.6 umol TE/g; DPPH = 404.6 umol TE/g) showed
the highest antioxidant activity of all tested samples of fruits and vegetables. Capsicum (Capsicum L.)
juices (TPC = 642.1 mg GAE/L; ORAC = 127.9 umol TE/g) and a radish (Raphanus sativus L.) extract
(ORAC 724.5 umol TE/g; DPPH = 52.2 umol TE/g) also proved to have the high values of antioxidant activity. From the tested fruits and vegetables the following inhibited to produce a nitric oxide: onion (Allium cepa L) juices (lowered the NO production by 57%), tangerine juices (Citrus reticulata Blanco)(by 52%), broccoli (Brassica oleracea var. botrytis italic) extract (by 21%), and orange (Citrus sinensis Pers.) extract (by 10%). Concerning edible
mushrooms, Lentinus tigrinus (Bull.) Fr. (TPC = 216.2 umol GAE/g of extract), Ganoderma lucidum (Curtis) P. Kras (TPC = 257.9 umol GAE/g of extract), and Royoporus badius (Pers.) A.B. De (TPC = 257.8 umol GAE/g of extract) presented the highest phenolic content. Sparassis crispa (Wulfen) Fr. (117.4 mg/g of extract) had the highest content of beta glucan. Substantial effect on phagocytic activity of granulocytes was noticed in connection with Neolentinus lepideus (Fr.) Redhead & Ginns, Polyporus squamosus (Huds.) Fr., and S. crispa. In connection with the latter of mentioned mushrooms, a moderate inhibitory effect towards HT 29 human colorectal adenocarcinoma cell line
(IC50 = 107 ug/ml of extract) was noticed.
The results indicate that the tested plants and mushrooms can be beneficial when reducing the negative effects of oxidative stress. The oxidative stress has been recognized as a contributing factor to a whole range of diseases and the reduction of the oxidative stress may lead to the decrease in the possibility of the diseases´ progression. The results show the possible favourable effects on the human health. When evaluating the results, the following fact should be taken into consideration; the in vitro tests and screenings are considered to be the first phase of systematic research of the effects and serve for the choice of respondents for further detailed studies.
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Provision of alternative refuse collection for a real estate surrounded by foreign property
Kvapil, Radek ; Štindl, Michal (referee) ; Klika, Pavel (advisor)
The thesis deals with possible ways of drainage and wastewater disposal. The issue of wastewater discharge to the environment has been closely monitored in recent years, and there is an apparent effort to improve the current situation.The dissertation discusses and compares three selected options – access to improved sanitation, building reservoirs and domestic wastewater treatment plant.The final section is dedicated to a comparison of acquisition and operating costs over time and to subsequent evaluation of the most suitable option. For the sake of clarity and assessment of potential solutions, the locality in the administrative area Vysoké Mýto - Domoradice has been selected as a model. The local authorities have been designing a public storm sewer, and given that it is surrounded by land, this issue will need to be addressed.
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Study of dielectrical properties of organic material thin films
Pospíšil, Jan ; Boušek, Jaroslav (referee) ; Mikula, Milan (referee) ; Zmeškal, Oldřich (advisor)
The dissertation is focused on the study of electric and especially dielectric properties of thin film organic materials with their huge potential for optoelectronics and other industrial sectors. The theoretical part deals with the use of organic materials in organic photovoltaic cells, the methods of deposition techniques and characterization. The theoretical knowledge of the dielectric spectroscopy, including methods for determining the physical properties and evaluation of experimental data are also described. The experimental part is devoted to the study of small molecule organic solar cells with bulk heterojunction composed of electron donor molecule of DPP(TBFu)2 and electron acceptor fullerene derivatives, such as PC60BM, PC70BM and TC60BM. The experimental part is divided into two main parts. The first part deals with the study of processes occurring at the interface between the active layer and the contact; the second part is focused on transport processes inside the structure of photovoltaic cells and also contains a study of perovskite solar cells.
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The study of the influence of the single entry and pillar mining method in seam No. 40 in Jan-Karel protective shaft pillar, location CSA Mining Plant 1 on Jan and shaft No. 2 downcast shafts and on the CSA 3 upcast air shaft, surface and surface objects
Ptáček, Jiří ; Kajzar, Vlastimil ; Koníček, Petr ; Kukutsch, Radovan ; Waclawik, Petr ; Jiránková, E.
The presented method single entry room and pillar solves the possibility of applying single entry room and pillar mining method, where roadheaders are used, newly in two variants. According to the first of them will be entries and intra-entries inundated with a time lag with fly ash mixtures. The second variant will be excavated only basic entries with a width of 6.8 meters. They will not be flooded. The purpose of the study is also adding calculations of potential and the expected impact of single entry room and pillar method on the surface and surface objects and also the expected impact on the shafts in Jan-Karel protective shaft pillar.
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Nation-building in Iraq after 2003
Aliová, Naďa ; Karásek, Tomáš (advisor) ; Střítecký, Vít (referee)
The main aim of the master thesis titled "Nation-Building in Iraq after 2003" is to evaluate the success of nation-building processes in Iraq between 2003 and 2011. The analytical approach of the German political scientist Jochen Hippler serves as a theoretical and terminological starting point. The thesis is divided into five chapters. The first chapter deals with the general and conceptional problems and of the terms "nation" and "nation-building". This is followed by a brief overview of Iraqi history. The next part is devoted to Hippler's three central elements of successful nation-building applied to the Iraqi context (i.e. integrating ideology, national integration and state-building). The third chapter explores whether ethnosectarian identities are subordinate to Iraqi national identity. The forth chapter is focused on Kurdish- Iraq relations and its potential implications for territorial (and economic) cohesion of Iraq and the following chapter deals with capabilities of the state apparatus concerning governance, providing security and delivering basic services. In conclusion, the level of success is summarized in the three dimensions respectively as well as with regad to overall nation- building process in Iraq.
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Analysis of the Economy of the Town Horní Planá
SOUČKOVÁ, Lucie
The diploma thesis is focused on budgetary economy of selected minucipality, in this case the town Horní Planá. There are described functions of the municipality, its institutions and a property, separation of the property and management with it. The thesis is focused on a budgetary economy of a municipality, a budget, a budget composition, where are defined budgetary incomes and expeditures and subsequently a budgetary outlook is analyzed there. The aim of this thesis is to analyze the economy of the town Horní Planá, which is performed on the data in the next five years, based on the analysis recommend possible measures to achieve the optimum relationship between the economy, efficiency and effectiveness, or finding potential funding sources. Partial aims are evaluation of the progression budgets in the period and to determine the effects of ganges of incomes and expenditures in different years, to analyze cash flow over the period and evaluate influences on cash flow and the analysis of the property of selected municipality and its funding.
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THE DRAMATICAL SCRIPT AS A NECESSARY BASIS FOR SPACIAL REALIZATOIN
Tretiag, Štěpán ; KORČÁK, Jakub (advisor) ; HRBEK, Daniel (referee)
Using the concrete examples of my practical bachelor work my intent is to retrospectively describe and reflect on our scenic realization of the play Missing by south-African author Reza de Wet. The essence of a modern dramatic direction is to perceive the script of a play as a model which becomes a basis for its interpretation and the subsequent staging of the play. It is the process from the initial interpretation to final scenic realization I wish to focus on in my work.In the first part I will be dealing with creation of a physical space, that being stage design. I will try to capture what lead us to its final shape and how the basis for that can be found in the script of the play as well as the potential capability of the physical space to become a dramatic space. Its ability to create a platform for the actors to proceed from and how can it provoke them into acting, in particular. In the second part I will be dealing with the dramatic space, ergo the spacial expression of relationships and themes. I will proceed again retrospectively, focusing on how we managed to achieve the stage image which is functioning as a materialized metaphor. I will focus mostly on non-verbal actions, but with regard to the fact, that dramatical script is the basis for our realization of the play.
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