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Lipid composition of biological membranes as a pace-maker of metabolic rate and life-histories
Šimonová, Kateřina ; Tomášek, Oldřich (advisor) ; Vojtek, Libor (referee)
Slože í iologi ký h e rá á zásad í vliv a pol e as e é ast é k seli , jako je apříklad DHA, jsou vel i itlivé k poškoze í vol ý i radikál , oproti o o e as e ý MUFA a as e ý SFA ast ý k seli á . předpokladu, že spolu s e as e ostí e rá se zv šuje o idač í u poškoze í a ásled ě r hlost stár utí, vz ikla a e akerová teorie stár utí Tato h potéza je slože á ze dvou částí. Prv í z týká souvislosti ezi slože í e rá a délkou života, kd živoči hové s ví e e as e ý i e rá a i s v šší pero idač í i de e a počte dvoj ý h vaze ěli ít, dík v šší itlivosti k o idač í u kratší délku života Tato část ašla této rešerši podporu. Druhá část týkají í se slože í e rá a r hlosti eta olis u, la větši ou studií v vrá e a. Me rá ů v šší r hlostí eta olis u spíše é ě e as e é oproti e rá á živoči hů po alejší eta olis e , se e ašla sig ifika t í korela e ož h potézou.
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Physiological adaptations associated with body size and longevity in endothermic vertebrates
Pazdera, Lukáš ; Tomášek, Oldřich (advisor) ; Blažek, Radim (referee)
Abstact Lifespan is related to a number of physiological processes that are interconnected. Longevous species are assumed to have evolved certain physiological adaptations that slow down ageing rate and enable long lifespan. The aim of my thesis was to review physiological traits that has been hypothesised to be associated with lifespan, and to evaluate the empirical support for such hypotheses. Studies testing the association of these traits with body size has also been included in my thesis, as body size is known to be tightly related to lifespan. Traits that are reviewed in my thesis due to their hypothesised coevolution with lifespan are as follows: metabolic rate (i.e., a total amount of energy expended by the organism per unit of body mass and unit of time), oxidative stress resistance, telomere length and rate of telomere shortening and intensity of stress and immune responses. Key words: Lifespan, longevity, survival, reproduction, oxidative stress, free radicals, reactive oxygen and nitrogen species, metabnolic rate, immunity, antioxidants
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Seasonality of reproduction in tropical birds
Kačírek, Vojtěch ; Sedláček, Ondřej (advisor) ; Tomášek, Oldřich (referee)
The aim of of this paper is to summarize the knowledge of reproduction seasonality of tropical birds. Work includes characteristics of individual tropical environment and changes in abiotic conditions, focusing on the question, in what sense are tropics aseasonal and what is not. The work includes an overview of methodologies for collecting data during field research focused on monitoring reproduction in birds. The main part of this work is to compare the differences between biogeographic regions, regions and their stimuli, which most commonly lead to the creation of seasonal reproduction, followed by a comparison of individual functional groups of birds (food guilds). Powered by TCPDF (www.tcpdf.org)
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Secondary sexual traits and ageing
Novotná, Kateřina ; Tomášek, Oldřich (advisor) ; Svobodová, Jana (referee)
Sexual selection is a key evolutionary mechanism that is based on differential reproductive success among individuals. Sexual selection drives evolution of sexual dimorphism and secondary sexual traits. These traits are often of ornamental character and may function as indicators of individual quality and viability in mate-choice. Ornamental traits may signal viability in two ways: either directly, when their expression reflects body condition and ornament predicts the probability of future survival; or indirectly, if their expression is age-dependent and intense ornament express only individuals that proved the ability to survive to old age. Ornament expression may also decline in old age, however, as a result of negative effect of senescence. The aim of my thesis was to assess, whether, and which, ornaments signal individual age and survival in free-ranging vertebrates with determinate growth and whether is ornament expression affected by senescence.
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Carotenoid allocation and redox homeostasis in birds
Mojžišová, Kateřina ; Tomášek, Oldřich (advisor) ; Svobodová, Jana (referee)
In many species carotenoid-based ornaments plays fundamental role in sexual selection. It is believed that carotenoid-based ornaments act as indicators of individual quality and condition during mate-choice, as associations between their expression, individual fintess and various condition indicators were observed. Despite the long-term research, mechanisms ensuring signalling honesty remain unknown. Currently, the most accepted hypothesis suggests antioxidant properties of carotenoids, and, therefore, a trade-off between their allocation to ornamentation or defence against free radicals. The antioxidant function of carotenoids in vivo was challenged in birds, however, and alternative hypotheses were proposed, assuming either carotenoid loss due to free-radical oxidation, or harmful (pro- oxidant) effects of high carotenoid levels in the body, or interconnection of metabolic pathways for both, the carotenoid conversion and homeostatic control of mitochondrial respiration and redox state. These hypotheses assume differing allocation of carotenoids under elevated oxidative stress, which we tested using experimental manipulations of oxidative state and carotenoid intake in adult male zebra finches (Taeniopygia guttata). The results are inconsistent with all the alternative hypotheses, but partly...
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Oxidative stress and condition-dependence of ornamental signals of quality in socially monogamous songbird
Valášek, Stanislav ; Tomášek, Oldřich (advisor) ; Sedláček, Ondřej (referee)
6 ABSTRACT Conditional ornaments plays irreplaceable role in sexual selection in non-small part of by sexual reproduction reproducing animals. Fastidiousness of generating and later also carrying of these ornaments which show condition of their wearer, burdens also metabolism in non-small scale. This thesis tests hypothesis of mutual addiction between conditional ornaments, as the indicators of qualities of individuals and metabolism, as the most significant source of free radicals which are responsible for oxidative stress. The real weight of influence of ornament fastidiousness on organism, resp. on redox state, is tested in this thesis. Manipulations which were performed with individual males of model species should point how much the selected factors correlate each other. The barn swallow (Hirundo rustica) is the model species. Analyses of dates collected during trapping which were realized in breeding seasons in 2012 and 2013 does not show any important trends between observing variables. This fact is confirmed by minimal differences and inconsistent variability of levels of measured antioxidants - oxidoreductases, superoxide dismutase and glutathione peroxidase. The marginal effect of manipulations with one of the conditional ornaments which are presented in model species supports the hypothesis of...
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Mechanisms of relationship between melanin-based colouration and behavioural syndromes in birds
Nacházelová, Martina ; Javůrková, Veronika (advisor) ; Tomášek, Oldřich (referee)
Melanins are the most common pigments incorporated into birds' feathers. Since melanin-based coloration is variable in the extent and intensity, its function is considered to be particularly cryptic and mechanical, hardening the feather structure. However, recently it has been found that melanin- based coloration also has a signaling function, due to the observed correlation between this type of coloration and many physiological and behavioral traits. These relationships follow from the pleiotropic effects of genes regulating the melanocortin system and the physiological effects of testosterone and corticosterone, which are involved in melanogenesis. This work describes genetic and physiological mechanisms of the relationship between melanin-based coloration and behavioral traits in birds and, based on available studies, supports the signaling function of this type of coloration. Melanin-based coloration has been shown to be positively correlated with aggressiveness and dominance, sexual activity, coping with stress, a fast strategy of exploratory behavior, parental care, and anti-predator behavior in many bird species. However, despite intense research interest in this topic in last decade, it is worth noting that more experiments focused on species with a distinct sexual dichromatism or...
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Physiological and hormonal mechanisms influencing ejaculate quality in birds
Mojžišová, Kateřina ; Tomášek, Oldřich (advisor) ; Svobodová, Jana (referee)
Sexual selection is an important mechanism of evolution. In addition to precopulatory sexual selection, arising when males compete for female partners, there is also postcopulatory sexual selection (sperm competition), when females copulate with more males. Even though most avian species are socially monogamous, most of them are also partially promiscuous. In such species, sperm competition is an important factor increasing variability in reproductive success between males. Male's success in sperm competition is primarily determined by sperm concentration, total sperm count and morphology and motility of spermatozoa. My bachelor thesis summarizes knowledge about the hormonal a physiological mechanisms that influence semen quality. This is especially the effect of sex and other hormones, physiological and oxidative stress, environmental conditions, antioxidant mechanism and composition of sperm cell membrane. Besides evaluating their influence on ejaculate quality on intraspecific level, I also describe their differences between avian species with respect to the differences of sperm competition.
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Outdoor Robot
Tomášek, Ondřej ; Burian, František (referee) ; Žalud, Luděk (advisor)
This work deals with navigation of the mobile outdoor robots. It is divided in two parts. In the first part, the mobile robots and their control problem is examined. The technical means for navigation and obstacles avoidance are described and the mathematical means for sensor data fusion and optimal position estimation of the robot are outlined. In the second part the hardware of the robot is described and furthermore it deals with description of the practically realized algorithms for obstacles avoidance and robot navigation.
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Guide to the Post-conference excursion Sandstone Landscapes: Diversity, Ecology and Conservation
Mikuláš, Radek ; Adamovič, Jiří ; Cílek, Václav ; Hendrych, J. ; Líčenková, M. ; Mertlík, J. ; Mrkáček, Z. ; Petříček, V. ; Tomášek, O. ; Šoltysová, L. ; Vacková, D. ; Herben, Tomáš ; Kopřivová, L.
The Kokořínsko PLA, Bohemian Paradise PLA and Polická vrchovina Highland represent a high-diversity "sandstone phenomenon". Sandstones of the Bohemian Paradise can be considered as optimum for development of microrelief features influenced by saet erosion and case hardening.
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