Recent evidence indicates that the mature neocortex retains a higher degree of plasticity than traditionally assumed. Up- and down-regulation of synaptic strength, long-term potentiation (LTP) and long-term depression (LTD), is thought to be the primary mechanism mediating experience-dependent plasticity of cortical networks. The present thesis investigate factors that regulate adult cortical plasticity, focusing on the role of neuromodulators, recent sensory experience, and different anatomical divisions of the cortex in influencing synaptic strength. First, I investigated the role of the neuromodulator histamine in gating plasticity in the primary visual cortex (V1) of urethane anesthetized adult rats. Histamine applied locally in V1 produced an enhancement of LTP elicited by theta burst stimulation (TBS) of dorsal lateral geniculate nucleus (dLGN) and allowed a sub-threshold TBS to produce stable LTP. Second, the impact of visual deprivation on LTP in V1 was assessed. Animals that received 2 and 5 hr dark exposure showed greater potentiation of field potentials when stimulated though retinal light flashes or weak TBS of the dLGN, which failed to induce LTP in control animals kept in continuous light. Third, I performed a detailed characterization of LTP induced by different TBS protocols, recording in either the monocular or binocular segment of both V1 hemispheres (i.e., ipsi- and contralateral to the stimulated dLGN). Stronger, NMDA receptor-independent LTP was found in the contralateral V1. Interestingly, weak TBS induced LTD that was NMDA receptor-dependent in the ipsilateral V1. Furthermore, a lower LTP induction threshold was observed in the binocular than the monocular segment of ipsilateral V1. Lastly, I investigated cholinergic modulation of sensory-induced activity in the barrel cortex. Basal forebrain stimulation enhanced multi-unit activity elicited by whisker deflection, an effect that was more pronounced for weaker response driven by a secondary whisker than principal whisker deflection. This thesis demonstrates that neocortical plasticity consists of multiple forms of synaptic modification. Adult cortical plasticity is greatly influenced by preceding activity of the synapse by various neuromodulator systems, and by anatomical subdivisions within primary sensory cortex fields. Together, these mechanisms may facilitate the detection, amplification, and storage of inputs to primary sensory fields of the neocortex. / Thesis (Ph.D, Psychology) -- Queen's University, 2010-04-29 14:02:30.742

Many molecules and the complex interactions between them underlie plasticity in the cerebellum. However, the exact relationship between cerebellar plasticity and the different signalling cascades remains unclear. Calcium-calmodulin dependent protein kinase II (CaMKII) regulates many forms of synaptic plasticity, but very little is known about its function during plasticity induction in the cerebellum. The aim of this thesis is to contribute to a better understanding of the molecular mechanisms that regulate the induction of synaptic plasticity in cerebellar Purkinje cells (PCs). The focus of the thesis is to investigate the role of CaMKII isoforms in the bidirectional modulation of plasticity induction at parallel fibre (PF)-PC synapses. For this investigation, computational models that represent the CaMKII activation and the signalling network that mediates plasticity induction at these synapses were constructed. The model of CaMKII activation by calcium-calmodulin developed by Dupont et al (2003) replicates the experiments by De Koninck and Schulman (1998). Both theoretical and experimental studies have argued that the phosphorylation and activation of CaMKII depends on the frequency of calcium oscillations. Using a simplified version of the Dupont model, it was demonstrated that the CaMKII phosphorylation is mostly determined by the average calcium-calmodulin concentration, and therefore depends only indirectly on the actual frequency of calcium oscillations. I have shown that a pulsed application of calcium-calmodulin is, in fact, not required at all. These findings strongly indicate that the activation of CaMKII depends on the average calcium-calmodulin concentration and not on the oscillation frequency per se as asserted in those studies. This thesis also presents the first model of AMPA receptor phosphorylation that simulates the induction of long-term depression (LTD) and potentiation (LTP) at the PF-PC synapse. The results of computer simulations of a simple mathematical model suggest that the balance of CaMKII-mediated phosphorylation and protein phosphatase 2B (PP2B)-mediated dephosphorylation of AMPA receptors determines whether LTD or LTP occurs in cerebellar PCs. This model replicates the experimental observations by Van Woerden et al (2009) that indicate that CaMKII controls the direction of plasticity at PF-PC synapses. My computer simulations support Van Woerden et al’s original suggestion that filamentous actin binding can enable CaMKII to regulate bidirectional plasticity at these synapses. The computational models of intracellular signalling constructed in this thesis advance the understanding of the mechanisms of synaptic plasticity induction in the cerebellum. These simple models are significant tools for future research by the scientific community.

Thesis (Ph.D. in Pharmacology) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 100-118).

Thesis (M.Sc.)--Memorial University of Newfoundland, 1998. / Typescript. Bibliography: leaves 84-96.

Thesis (M.Arch.)--University of Hong Kong, 2002. / Includes special study report entitled : Art and garden in health care design. Includes bibliographical references. Also available in print.

The basic theoretical basis: According to demographic development the average and maximum lifespan prolongs. Therefore global population spends a bigger part of adulthood in their old age. This phenomenon is irreversible and brings significant changes into global geriatric nursing and we need to take note of the care that is provided to old patients. The seniors form an irreplaceable and a more and more considerable part of population, they create a varied group with individual needs, priorities and demands in sickness as in health. It is the very polymorbidity of senior patients which is often the reason for a long-term hospitalization. Nowadays, for these purposes more and more beds are built in long-term care facilities (LTCF) which are officially defined as specialized medical institutions which provide care to patients whose health states cannot be substantially improved by any medical treatment as they worsen without a continuous care. The life quality of seniors and the quality of the provided care in these facilities are the main long-term care level indicators. The goals of the thesis: 1) Ascertain the life quality of seniors hospitalized in long-term care institutions. The research questions: 1) How does the hospitalization of seniors in LTCF influence their subjectively perceived quality of life? 2) In which areas do seniors hospitalized in LTCF feel the difference of life quality in LTCF and at home? 3) How are the patients in LTCF satisfied with the quality of health care? 4) Within the rise of seniors' life quality in LTCF, in which areas should the nurse improve the provided care? Methods employed: For the empirical part of the thesis the qualitative analysis of gathered data method was used. The data accumulation was implemented by semi-structured interviews with clients-patients hospitalized in LTCF. The instructions for the interviews were adopted from a QOL Research Unit life quality model of the university in Toronto. This model emphasizes the individual's relations towards the surroundings and the possibilities of maintaining and improving skills. It is divided into 3 categories - existence, togetherness and adaptability. Interview transcriptions create a part of the thesis on an enclosed CD. For illustrative purposes, the results of the research were transformed into mind maps using the XMind software. There are also annotations with respondents' quotations concerning individual map as a part of the thesis. The results: The analysis of in-depth interview gathered information brought several factors which are highly subjective and have a logical level of individuality. The results concerning the research of the seniors' life quality dimensions are more or less in agreement with the basic division found in professional literature. However, they bring a further view on these dimensions and introduce subjective opinions, wishes and evaluation of seniors who found themselves in unknown environment of LTCF. The positive influence of nurses, which often impact the satisfaction of seniors in a medical institution, proved its importance. However, it was the area of communication skills of medical staff which was mentioned as lacking or insufficient. Also the fields of free time activities, seniors' adaptation in LTCF and social isolation were found to be neglected. Conclusion: The long-term care becomes, thanks to demographic development, the most rapidly evolving kind of health care. The emphasis on life quality of hospitalized seniors, as their biggest consumers, should be a matter of course for every medical and social facility. The contribution of the thesis is in detailed mapping of the issue of life quality in LTCF, warning against lack in health care and the neglected fields of life quality.

abstract: Anti-trafficking research recognizes several populations affected by Commercial Sexual Exploitation (CSE) in the United States (U.S.), yet it has not yet recognized long-term survivors, whose experiences of CSE occurred from the 1960s through the 2000s. Rendering long-term survivors invisible erases the history of CSE in the U.S. and prevents an accurate assessment of the true scope of CSE that it extends from infancy through adulthood. The most grievous CSE cultures target both boys and girls beginning at infancy and extending through early childhood. This project provides a foundation for understanding who long-term survivors are, the types of CSE they experienced, and their experiences of survivency in the decades after exiting. This study utilized interviews and surveys to collect data from 35 long-term survivors, regarding their experiences in the years past exiting. In addition, it also included a systematic analysis of 43 survivor-authors who have documented their experiences in 76 published writings. Findings show that long-term survivors display tenacity and resourcefulness in dealing with complex, intersecting issues. Their experiences of creating new, meaning-filled identities, reconnecting with humanity, and building a positive view of the world can help pave the way for a smoother road of restoration for younger survivors. / Dissertation/Thesis / Doctoral Dissertation Justice Studies 2019

Long-term potentiation (LTP) and depression (LTD) are activity dependent long-lasting changes in synaptic efficacy and have been proposed as mechanisms for learning and memory. Although the exact relationship of LTP and LTD to memory is not known, they do share some properties and mechanisms that relate to memory, such as the strengthening and weakening of synapses. LTP and LTD have been studied extensively in hippocampal brain-slice preparations, due to its relatively organized structure, ease of induction, and its critical function in memory storage. Less work has been done in the neocortex despite the belief that it is heavily involved in the storage of long-term memories. Activity dependent plasticity has also been demonstrated in the basal ganglia in vivo and in vitro, but the results have been somewhat inconsistent. The experiments presented in this thesis explore a novel form of neural plasticity in two excitatory pathways (corticostriatal and thalamocortical) of the basal ganglia motor loop in the intact brain in awake, freely behaving rats. In thalamocortical slice preparations, simultaneous presynaptic stimulation and postsynaptic depolarization can induce L TP in animals prior to the critical period. However the results presented in this thesis show that applied stimulation to the thalamocortical pathway failed to produce either LTP or LTD in the awake freely moving animal.Corticostriatal LTD has been shown in slice preparations following direct tetanic stimulation of the striatum. In the current experiment, cortical stimulation failed to induce LTD although there was an observable decrease in the evoked potential following low-frequency stimulation. Corticostriatal L TP has been shown to depend on the type of stimulation applied. High-frequency and theta burst stimulation produced long-lasting changes in response amplitude in the corticostriatal pathway, with theta burst stimulation appearing to be the more effective stimulation protocol for inducing LTP in both the early and late components. Paired stimulation of the substantia nigra pars compacta and cortex indicated a modulatory action of dopamine on corticostriatal synaptic plasticity. Pairing led to a stable increase in the amplitude of LTP of both early and late components. We also report that a temporal relationship exists in the striatum with respect to the release of nigral dopamine and cortical glutamate. Simultaneous stimulation produced a more robust L TP compared to the two other conditions in which there was an applied stimulation delay to either the corticostriatal or nigrostriatal pathway. The results demonstrate the mechanistic differences, not only between the thalamocortical and corticostriatal pathways, but also slice and anesthetized preparations. The results also emphasize the need for further study on mechanisms of L TP and LTD in the various excitatory and inhibitory pathways of the basal ganglia motor loop. / Thesis / Doctor of Philosophy (PhD)

No description available.

The subject of my thesis is "Comparison of development of depreciation methods of long-term assets and their influence on the tax base". The aim of this study was to capture the development of methods of depreciation, amortization of transferring these methods into the numerical expression and assess the impact of the development of depreciation to the tax base. This work does not cover only the current depreciation issues, but focuses on the development of depreciation for the period from 1995 to 2010. Development of income taxes, depreciation rates and coefficients from 1995 - 2010 was favorable for taxpayers. The tax rate was decreasing. Depreciation rates have increased and rates fell, which provoked a reduction of the minimum period of depreciation.