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Computational models of motor adaptation under multiple classes of sensorimotor disturbanceHaith, Adrian January 2009 (has links)
The human motor system exhibits remarkable adaptability, enabling us to maintain high levels of performance despite ever-changing requirements. There are many potential sources of error duringmovement to which the motor system may need to adapt: the properties of our bodies or tools may vary over time, either at a dynamic or a kinematic level; our senses may become miscalibrated over time and mislead us as to the state of our bodies or the true location of an intended goal; the relationship between sensory stimuli and movement goals may change. Despite these many varied ways in which our movements may be disturbed, existing models of human motor adaptation have tended to assume just a single adaptive component. In this thesis, I argue that the motor system maintains multiple components of adaptation, corresponding to the multiple potential sources of error to which we are exposed. I outline some of the shortcomings of existing adaptation models in scenarious where multiple kinds of disturbances may be present - in particular examining how different distal learning problems associated with different classes of disturbance can affect adaptation within alternative cerebellar-based learning architectures - and outline the computational challenges associated with extending these existing models. Focusing on the specific problem in which the potential disturbances are miscalibrations of vision and proprioception and changes in arm dynamics during reaching, a unified model of sensory and motor adaptation is derived based on the principle of Bayesian estimation of the disturbances given noisy observations. This model is able to account parsimoniously for previously reported patterns of sensory and motor adaptation during exposure to shifted visual feedback. However the model additionally makes the novel and surprising prediction that adaptation to a force field will also result in sensory adaptation. These predictions are confirmed experimentally. The success of the model strongly supports the idea that the motor system maintains multiple components of adaptation, which it updates according to the principles of Bayesian estimation.
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Vliv chladového stresu na imunitní systém za působení infekčních agens / The effect of cold stress on the immune system in the presence of infectionKratochvílová, Anna January 2021 (has links)
Although the relationship between the effects of cold and infection has been studied for a long time, the mechanisms contributing to this phenomenon have not yet been discovered. While short-term exposure to cold triggers a stress response and the production of proinflammatory cytokines, long-term cold exposure induces adaptation and anti- inflammatory shift. The role of cold adaptation in the development and the process of the organism's response to infection remains an unresolved issue. In this diploma thesis, we focused on determining the effect of cold stress or cold adaptation on the immune system of rats which was stimulated by ligands of Toll-like receptors (TLRs). The obtained results showed the importance of γδT lymphocytes and their cytokine production in the process of cold adaptation. To determine how cold adaptation affects the response to infectious agents, we studied changes in the proportion of different immune cell populations in rats treated with the TLR2/6 ligand Pam2CSK4. We determined significant changes in the activation of myeloid cells and B lymphocytes, but also in the population of γδT lymphocytes. Our obtained results suggested the importance of γδT lymphocytes and the protective effect of cold adaptation. Key words: immune system, cold stress, cold adaptation, infection,...
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Совершенствование системы адаптации молодых работников на промышленном предприятии : магистерская диссертация / Perfection of system of adaptation of young workers at the industrial enterpriseПавлос, А. В., Pavlos, A. V. January 2017 (has links)
Работа содержит теоретический анализ отечественной и зарубежной литературы по вопросам адаптации молодых работников на промышленном предприятии, а также результаты эмпирического исследования системы адаптации молодых работников на Качканарском горно-обогатительном комбинате. Автор выявил проблемы адаптации и доказал, что система адаптации молодых работников на предприятии будет более эффективна (оптимальна) при усовершенствовании работы в сфере наставничества. Диссертация содержит проекты «Школа наставников», внедрение которого имеет экономический эффект. / The work contains theoretical analysis of domestic and foreign literature on adaptation of young workers in an industrial plant, as well as the results of empirical research of the system of adaptation of young employees at Kachkanarsky GOK. The author has identified problems of adaptation and proved that the system of adaptation of young employees at the enterprise will be more efficient (optimal) if the area of mentoring will be enhanced. The thesis contains the project "School of masters", the introduction of which has an economic effect.
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