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Body size as an implicit factor: case studies of life-history strategies and behaviour
Šimková, Olga ; Frynta, Daniel (advisor) ; Sedláček, František (referee) ; Rehák, Ivan (referee)
Body size has a potential to influence almost any trait in animal biology. The thesis contains four case studies (I - IV) covering four various situations and four various taxa, mainly squamate reptiles (Lepidosauria). Body size is a connecting factor for all these studies, in which I and my co-authors tried to elucidate various implications of body size. I. The sex ratio in Cuban boa (Chilabothrus angulifer) litters is often male or female biased. The neonates are so large, that are able to accept the same type of prey as are adults (in contrast to the other Chilabothrus species). We found that both the sexes are of the same size and shape at birth. Large size of the neonates a long lifespan lead to considerable generation overlaps. This could clarify our findings that small females produce sons whereas the larger ones deliver daughters. Males are smaller than females, probably also less philopatric and refuse food during breeding season. We can conclude that females manipulate the sex ratio of neonates according to its own body size, in order to decrease the probability of competition with their own offspring. II. Mangrove-dwelling monitor lizard (Varanus indicus) shows one of the greatest degrees of sexual size dimorphism among monitor lizards. We recorded the growth of the individuals from...
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Ontogeny and evolution of body size and sexual size dimorphism in reptiles
Frýdlová, Petra ; Frynta, Daniel (advisor) ; Moravec, Jiří (referee) ; Zrzavý, Jan (referee)
Monitor lizards (Varanidae) are morphologically very uniform in body shape, but much diversified in body size along both phylogenetic and ontogenetic axes. A striking sexual size dimorphism exists in monitor lizards; they are capable of fast growth, metabolism and sexual maturation. I collected the data concerning body size of particular species and verified the validity of Rench's rule, which said that there is bigger difference in body size of a conspecific male and females growing with larger body size of the species. Males are markedly bigger than females. In the next step, I focused on the model species of monitor lizards, Varanus indicus. I monitored its ontogeny very carefully. I found that this monitor lizard has pronounced sexual size dimorphism, but there are only small differences in body shape. It is capable of rapid growth and sexual maturation. The sexual dimorphism in body shape is only poor, but still measurable right in those places where the selection pressures were expected. Blood sampling monitored biochemical and haematological parameters. The concentrations of the biochemical parameters revealed the economy of resources of particular sexes partially, the costs of body growth and reproduction. Although both sexes produce the same amount of biomass (the body growth of males vs. the...
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Lizard growth and the ontogeny of sexual size dimorphism
Meter, Brandon ; Starostová, Zuzana (advisor) ; Kupfer, Alexander (referee) ; Vrtílek, Milan (referee)
Růst byl u plazů historicky považovaný za neukončený. Tento obecně sdílený předpoklad byl v posledních letech zpochybněn a narůstaly důkazy o ukončeném růstu u ještěrů. Tento obrat způsobila především analýza růstových plotének kostí, která ukázala jejich uzavření a tím nemožnost dalšího prodlužování kostí, což způsobuje dosažení konečné velikosti těla. Paralelně s touto změnou v nahlížení na ukončený růst byly zpochybněny i dlouhodobé předpoklady o zásadní přímé roli energetického rozpočtu a s ním spojených trade-offs v ovlivňování růstu. Tento posun v perspektivě ovlivňuje nejen naše chápání individuálního růstu, ale také se odráží ve studiu souvisejícího znaku - pohlavního dimorfismu ve velikosti (SSD) - rozdílu ve velikosti mezi pohlavími v rámci druhu. Existují tři hlavní hypotézy o příčinách SSD u plazů: pohlavně-specifické náklady na reprodukci, ovlivnění růstu samčími gonadálními androgeny a ovariálními hormony. Tato práce přináší další důkazy o ukončeném růstu u ještěrů a diskutuje jeho důsledky pro evoluci SSD. Review o růstu zaměřené na gekona Paroedura picta, kde jsou větší samci než samice, zdůrazňuje značnou kanalizovanost růstu a současně poskytuje základ o úvahách týkajících se proximátních příčin SSD. V této práci dále předkládám podporu pro pravděpodobnou roli ovariálních hormonů...
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The Influence of Social Networks on Parents in Relation to Infant and Toddler Nutrition
Hromadová, Lenka ; Weidenthalerová, Edita (advisor) ; Honzejková, Kateřina (referee)
This bachelor thesis focuses on the influence of social networks on parental decision-making regarding infant and toddler feeding. Early nutrition is critical to child development and influences future health. Parenting is a decision-filled challenge, especially with such a vast amount of information from various sources, including social media, which can cause confusion and uncertainty about the best childcare. The aim of this paper is to assess how much parents trust information from influencers compared to expert recommendations, and how social media influences their preferences regarding their children's nutrition. The theoretical section covers the basics of nutrition in the first three years of life, including breastfeeding, infant formula, and transition to solid foods. The practical part explores how parents use social networks as a source of information about infant and toddler nutrition and how this information influences their decision-making. This section also analyses trends and myths on social media. The results show that parents strongly trust pediatricians and consider them a reliable source of information on child nutrition, in contrast to low trust in advice and recommendations from influencers. This result suggests that parents tend to rely on verified experts. Providing accurate and...
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Impact of selected probiotic bacteria on juvenile host growth in gnotobiotic mouse model
Drgoňová, Veronika ; Janďourek, Ondřej (advisor) ; Konečná, Klára (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Study program: Pharmacy Author: Veronika Drgoňová Supervisor: PharmDr. Ondřej Janďourek, Ph.D. Consultant: Mgr. Martin Schwarzer, Ph.D. Title of diploma: Impact of selected probiotic bacteria on juvenile host growth in gnotobiotic mouse model This thesis expands understanding of the ability of Lactiplantibacillus plantarum WJL bacteria to support the growth of gnotobiotic hosts in models of chronic malnutrition. It was investigated whether other bacteria also have similar capabilities and whether these traits are species- and strain-specific. Strains of Bifidobacterium longum ssp. longum and Bifidobacterium adolescentis were tested in a gnotobiotic juvenile mouse model of chronic malnutrition and their impact on the host's somatotropic axis was monitored. Concurrently, it was analysed how malnutrition affects the bacteria in the host's gut and the level of its colonization. Germ-free C57BL/6J mice were mono-colonized via intragastric gavage with the aforementioned bacterial strains. The mice were mated after confirming stable colonization and F1 male offspring were weaned on the 21st day after birth onto an experimental diet with low protein and fat content. Their growth was monitored weekly by...
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Workplace reconstruction project
Šmahel, Jiří ; Bartošek, Vladimír (referee) ; Juřica, Pavel (advisor)
This master's thesis focuses on managing a workplace reconstruction project, from which the company anticipates opportunities for growth and improvement of individual processes. The selected company has been dealing with issues of insufficient production capacity and the segregation of its workplaces for a long time. One potential solution is relocating to another facility, however it requires reconstruction first. The thesis contains a proposal how such a reconstruction could take place.
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NPS Customer Loyalty Analysis and Proposals for its Strengthening
Klvaňa, Martin ; Sieck,, Ellen (referee) ; Konečná, Zdeňka (advisor)
Tato diplomová práce je zaměřená na možnosti posílení loajality zákazníků společnosti Atlas Copco Compressor Technique. Teoretická část objasňuje pojmy jako marketingový výzkum, dotazník, zákazník či loajalita. Závěr první části je věnován modelu Net Promoter Score, programu, který je také použit k vypracování samotné analýzy součastné spokojenosti a loajality zákazníků. Výsledky z této analýzy spolu s pozorováním, které autor v podniku provedl, slouží v závěrečné části práce k návrhům, které by měly mít za následek zvýšení počtu loajálních zákazníků této společnosti.
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Evaluation of Building Company
Palasová, Lenka ; Puchýř,, Bohumil (referee) ; Hroníková, Marta (advisor)
Master`s thesis named „Evaluation of Building Company“ is focused on the explanation of the concept of value and his various forms and use, the definition of procedure of evaluation of company, some parts of the procedure are broken down, but the main part of this thesis is a description of used methods of evaluation of company. In the practical part particular company is evaluated by selected methods based on statements of accounts and other obtained information.
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Mutual interaction of multiple cracks growing in the particulate composite with brittle matrix under conditions of sub-critical crack growth
Slávik, Ondrej ; Ševeček, Oldřich (referee) ; Majer, Zdeněk (advisor)
In the first part of the submitted diploma thesis, the knowledge in the sphere of the fracture mechanics, related to the practice part of this thesis are summarized. In that the 2D parametrical numerical model of the particle composite with multiple cracks was created, using the finite elements method. Thanks to this model it is possible to find specific configurations which are showing the existance of multiple mutual interactions between these cracks, just by simple manipulation of the input data. In the calculations the influence of the residual stresses was considered which are formed during production of the material. The effect of the subcritical crack growth was taken into account as well in this thesis.
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