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Brains of African mole-rats in numbers: Data for testing the social brain hypothesis
Kverková, Kristina ; Němec, Pavel (advisor) ; Pavelková, Věra (referee)
The social brain hypothesis (SBH) posits that complex social environments exert a major selection pressure driving the evolution of large brains and intelligence. The hypothesis was first proposed to explain the remarkable cognitive abilities of primates and has since been extended to other vertebrate groups and gained a substantial popularity. Nevertheless, the empirical support is equivocal in virtually every group where the hypothesis has been tested. In this thesis, the SBH is tested in the African mole-rats (Bathyergidae). Mole-rats share a subterranean mode of life and similar ecologies while covering the whole social spectrum, from solitary to "eusocial". The number of brain neurons is considered a better proxy for intelligence than relative or absolute brain size. Therefore, a novel approach, the isotropic fractionator, was used to estimate the total number of neurons and other cells in five brain parts (olfactory bulbs, cerebral cortex, cerebellum, diencephalon and basal ganglia, brain stem) of eleven bathyergid species. This simultaneously allows for examining if and how mole-rats differ from other rodents with respect to brain cellular scaling rules. We found that, contrary to expectations, mole-rats generally conform to these rules, with a few exceptions. They tend to have higher...
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Physiology of special mirror eyes of molluscs, crustaceans and deep-sea fish
Remišová, Kateřina ; Hudec, René (advisor) ; Němec, Pavel (referee)
The majority of image forming systems in animal eyes are based on refractive optics. However, there are several eye types that use as a main image forming devises biological mirrors hence they are called mirror eyes. Biological mirrors are special type of tissue that reflects light beams usually by means of the constructive interference on multi-layers of alternating refractive indices. The mirror eye arrangement can be found mostly in animals living in the dim or deep water. Different types of mirror eyes have been described among molluscs, crustaceans and fishes. Moreover, the reflective superposition eyes of decapod crustaceans served as an inspiration for construction of the lobster-eye X- ray telescopes used in astrophysics. In this thesis, various types of mirror eyes are described. The overview of animals with mirror eyes is supplemented by description of their habitat. Finally, different types of mirror eyes are compared and their possible biomimetic application especially in optical technology is discussed. Powered by TCPDF (www.tcpdf.org)
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Interaction between performances in different cognitive tests: discrimination learning vs numerical competence tests and influence of the social status in the group
Kovácsová, Denisa ; Landová, Eva (advisor) ; Němec, Pavel (referee)
Absolute numerousness judgement (ANJ) is numerical competence in which the concrete number is discriminated. ANJ hasn't been tested in pigeons (Columba livia) yet. Therefore six individuals were tested in discrimination of number "three" from ratio 2 vs. 3: two pigeons on "touch screen" and all six by opening small bowls that were closed by discriminated stimulus. Pigeons didn't reach required level of 70 % (they answered with success approx. 30 - 65 %) in any testing environment. Mixed presentation was created such as control of size, possition and shape of discrimination stimulus. It was also studied wheather pigeons used alternative strategies. Success in ANJ was compared with previous discrimination tasks (Kocourková, 2016) in both environment (discrimination of reduced black and white stimulus on the cap and discrimination of round-shaped black and white areas in the Skinner box). If was found out that pigeons weren't able to learn in the same condition discrimination 2 vs. 3 stimulus during the same number of trials which they needed in the previous discrimination task. During answering to the stimulus they didn't use any alternative strategies with one exception. The effect of social hierarchy in the group on the performance of pigeons wasn't found out. Keywords: Columba livia, numerical...
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Social Brain Hypothesis: A Survey of Evidence
Kverková, Kristina ; Němec, Pavel (advisor) ; Pavelková, Věra (referee)
The social brain hypothesis was first proposed to explain the remarkable cognitive abilities of primates and has since been extended to other taxa. Generally, it posits that sociality is a major selection pressure driving the evolution of large brains and intelligence. However, there is no single version of the hypothesis and different underlying mechanisms have been proposed. Tests of the hypothesis rely on appropriate indices of social complexity and brain size, as a proxy for cognitive abilities, and difficulties are associated with choosing both these variables and obtaining precise data. Situation is further complicated by that fact that a multitude of factors potentially contributing to or constraining encephalization is highly intercorrelated. This bachelor's thesis reviews approaches to research in this field and presents a survey of relevant evidence accumulated so far. The social brain hypothesis has been tested in various ways in primates, carnivores, ungulates, cetaceans, insectivores, bats, birds, fish (cichlids), and insects. The jury is still out, since contrasting results exist for most of these groups, warranting more research to help elucidate the influence of sociality on brain evolution.
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Missa chrismatis and Its Changes in the Twentieth Century: A Comparison of Changes in Liturgy and Theology
Němec, Pavel ; Kotas, Jan (advisor) ; Opatrný, Aleš (referee)
Missa chrismatis and Its Changes in the Twentieth Century: A Comparison of Changes in Liturgy and Theology. Missa Chrismatis (Chrism Mass) is a Mass that the bishop celebrates in the Holy Week, together with his priests, which is a sign of mutual unity. During this Mass, the priests renew their priestly vows and the bishop consecrates the oil of catechumens, the oil of the sick and the chrism oil. The ceremony underwent several changes over the past century. These are reflected also in the theology, expressed in the liturgy by emphasizing of certain elements. The major reforms of the liturgy of the Mass took place in several stages in the 50`s, 60`s and 70`s of the 20th century. First, the thesis follows the basics and reasons for the use of oils in the liturgy of the Catholic Church in the context of Easter and then the historical development of the Mass, in which the oils are consecrated. Also it clearly compares the progress of the Missa chrismatis liturgy and captures differences in the liturgical texts and texts of the rite of benediction of oils in the various phases of the reform of the twentieth century. On this basis, it attempts to render the evolution in theological content. Keywords Missa Chrismatis, Benediction of Holy Oils, Chrism, The Holy Week, Maundy Thursday, Liturgical Reform.
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Neural Basis of magnetic compass orientation in C57BL/6J mice
Bláhová, Veronika ; Němec, Pavel (advisor) ; Druga, Rastislav (referee)
The ability to perceive the Earth's magnetic field has been demonstrated in a variety of animals, including representatives of all five classes of vertebrates. The physiological mechanisms underlying magnetic field sensation, however, remain largely unknown. Behavioral, physiological, neuroethological studies and studies using early response genes as neuronal activation markers indicated that a major role in the perception and processing of magnetic information play trigeminal, vestibular and visual systems. Subsequently, magnetic information seem to be integrated with multimodal sensory and motor information within the hippocampal-entorhinal system. In the majority of studies, however, birds have been used as model organisms. In this work I analyzed the neural substrate of magnetic compass orientation in the mouse strain C57BL/6J using markers c-Fos and Egr1. I found that all the aforementioned systems contain neurons responsive to the experimental magnetic fields. This finding demonstrates a complex processing of the magnetic information at level of the central nervous system.
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Magnetic field effects on exploration behaviour of rodents
Štefanská, Lucie ; Němec, Pavel (advisor) ; Sedláček, František (referee)
Magnetoreception, i.e., the ability of animals to detect magnetic field parameters, has been described in a number of phylogeneticaly distant species, including mammals. Animals that regularly undertake long migrations, as well as non-migratory species, are able to make use of directional information derived from the Earth magnetic field. Recently, this ability has been documented in laboratory mice from the C57BL/6J strain, which were used as the model organism also in our study. The aim of this thesis was to analyze the locomotory activity and behavioral parameters in mice exposed to various experimentally manipulated magnetic fields in an open field test (OFT). Overall, the effect of experimental magnetic fields on activity level and behaviors of C57BL/6J mice during OFT exploration was rather weak. Nevertheless, a detailed analysis revealed that magnetic fields influenced the angular velocity of mice in the first 20 minutes of the OFT and the following behaviors: grooming, digging, and nose-to-wall contacts. Different parameters of magnetic fields affected different behaviours in a specific manner. Changes of behavior in time were most visibly affected. These results remain open to interpretation, however, it seems that the experimentally manipulated magnetic fields might represent stimulus...
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Color vision in primates: Neurobiology and behavior
Skalníková, Petra ; Nekovářová, Tereza (advisor) ; Němec, Pavel (referee)
Trichromacy is the condition that involves three independent channels for processing color information based on three different cone types. Most mammals have dichromatic vision, trichromacy appears in primates of the Old World (including human) and partly in the New Wold primates. This thesis focuses on the mechanisms of trichromatic vision, its evolution in primates and the comparison of the primates of the Old and New World. The neuronal mechanisms underlying both trichromatic and dichromatic vision will be discussed, however we focus particularly on the potencial hypothesis for the evolution of trichromatic color vision in primates. Powered by TCPDF (www.tcpdf.org)
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Nursing Care in Patient with Acute Myocardial Infarction
Němec, Pavel ; Hošťálková, Monika (advisor) ; Burišková, Klára (referee)
The aim of this bachelor thesis is to identify the characteristics of prehospital and hospital care of patients with acute myocardial infarction. The theoretical part of the thesis summerizes clinical symptoms, diagnostical procedures and treatment of such patients. There is mentioned the importance of preventive steps, also. The differences in prehospital and hospital nursing care of acutelly ill patient are examined in detail. The practical part of the thesis uses data of Pilsen Region Rescue Service and analyzes the incidence of acute myocardial infarction in this area. Furthermore, two case studies discuss the appropriateness of nursing care. Key words: acute myocardial infarction, interventional treatment, nursing care, nursing diagnose, interventional treatment, patient
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Scaling of intelligence in mammals focused on cognitive abilities of primates
Tesař, David ; Landová, Eva (advisor) ; Němec, Pavel (referee)
Currently, there are two prevailing theories explaining the distribution and evolution of intelligence (higher cognitive) skills in animals. The first hypothesis considers that the terms of general principles of intelligence common to at least all vertebrates and individual taxa, according to this hypothesis, differ only quantitatively. The second hypothesis is based on the assumption that every animal is its cognitive abilities perfectly adapted to their environment and that it is therefore a mental adaptation to changing environmental conditions. The prerequisite of this hypothesis is the existence of qualitatively different types of cognitive abilities (types of intelligence). The aim of this work would be to provide a broader view regarding the measurement of intelligence and hypotheses concerning its development. Furthermore, the evaluation of the success of the model types of cognitive tests in primates, their interspecies comparison and for comparison with human and also compared the relative success with brain size and other factors.
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