Time-dependent cosmic ray modulation in the heliosphere is studied by using a two-dimensional time dependent modulation model. To compute realistic cosmic ray modulation a compound approach is used, which combines the effect of the global changes in the heliospheric magnetic field magnitude and the current sheet tilt angle to establish realistic time dependent diffusion and drift coefficients. This approach is refined by scaling down drifts additionally (compared to diffusion) towards solar maximum. The amount of drifts needed in the model to realistically compute 2.5 GV proton and electron and 1.2GV electron and helium intensities, as measured by Ulysses from 1990 to 2004, is established. It is shown that the model produces the correct latitudinal gradients evident from the observations during both the Ulysses fast latitude scan periods. Also, much can be learned on the magnitude of perpendicular diffusion in the polar direction, K┴θ, especially for solar minimum conditions and for polarity cycles when particles drift in from the poles. For these periods K┴θ = 0.12K║ in the polar regions (with K║ the parallel diffusion coefficient)and K┴θ /K║ can vary between 0.01 to even 0.04 in the equatorial regions depending on the enhancement factor toward the poles. The model is also applied to compute radial gradients for 2.5 GV cosmic ray electrons and protons in the inner heliosphere. It is shown that, for solar minimum, and in the equatorial regions, the protons (electrons) have a radial gradient of 1.9 %/AU (2.9 %/AU), increasing for both species to a very fluctuating gradient varying between 3 to 4 %/AU at solar maximum. Furthermore, the model also computes realistic electron to proton and electron to helium ratios when compared to Ulysses observations, and charge-sign dependent modulation is predicted up to the next solar minimum expected in 2007. Lastly the model is also applied to model simultaneously galactic cosmic ray modulation at Earth and along the Voyager 1 trajectory, and results are compared with> 70 MeV count rates from Voyager 1 and IMP8. To produce realistic modulation, this model gives the magnitude of perpendicular diffusion in the radial direction as K┴r/K║= 0.035 and that the modulation boundary seemed to be situated between at 120 AU and 140 AU. / Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2005.

Primary visual cortex is a classic model to study experience-dependent brain plasticity. In early life, if one eye is deprived of normal vision, there can be a dramatic change in the ocular dominance of the striate cortex such that the large majority of neurons lose responsiveness to the deprived eye and, consequently, the ocular dominance distribution shifts in favor of the open eye. Interestingly, the visual experience dependent plasticity following monocular deprivation (MD) occurs during a transient developmental period, which is called the critical period. MD hardly induces ocular dominance plasticity beyond critical period. The mechanisms underlying ocular dominance plasticity during the critical period are not fully understood. It has been proposed that long-term depression (LTD) may underlie the loss of cortical neuronal responsiveness to the deprived eye. However, discordant results have been reported in terms of the role of LTD and LTP in visual plasticity due to the lack of specific blockers. Here we report the prevention of the normally-occurring ocular dominance (OD) shift to the open eye following MD by using a specific long-term depression (LTD) blocking peptide derived from the GluR2 subunit of the a-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid receptor (AMPAR). We were able to prevent the shift of OD to the open eye with systemic or local administration of the GluR2 peptide. Both electrophysiological and anatomical approaches were taken to demonstrate the peptide effect. Moreover, enhancing LTD with D-serine, a NMDA receptor co-agonist, brought back the ocular dominance plasticity in adult mice subject to four-day MD and, therefore, reopened the critical period. Our data indicate that LTD plays an essential role in visual plasticity during the critical period and the developmental regulation of LTD may account for the closure of critical period in adult. In an additional study, we have found anisomycin, a protein synthesis inhibitor, produces a time-dependent decline in the magnitude of the field EPSP (fEPSP) in mouse primary visual cortex and that this anisomycin-mediated fEPSP depression occludes NMDA receptor dependent LTD. In contrast, another two protein synthesis inhibitors, emetine and cycloheximide, have no effect either on baseline synaptic transmission and or on LTD. We propose that anisomycin-LTD might be mediated by p38 MAP kinase since anisomycin is also a potent activator of the P38/JNK MAPK pathway. In agreement with notion, the decline of the fEPSP caused by anisomycin can be rescued by the application of the P38 inhibitor SB203580, but not by the JNK inhibitor SP600125. The occlusion of LFS-LTD by anisomycin-induced fEPSP decline suggests that common mechanisms may be shared between the two forms of synaptic depression. Consistent with this view, bath application of the membrane permeant peptide discussed above, which specifically blocks regulated AMPA receptor endocytosis, thereby preventing the expression of LFS-LTD, prior to anisomycin treatment significantly reduced the anisomycin-induced decline of the fEPSP. In conclusion, this study indicates that anisomycin produces long-lasting depression of AMPA receptor-mediated synaptic transmission by activating P38 MAPK-mediated endocytosis of AMPA receptors in neonatal mouse visual cortex.

Background: There is little information on how the quality of oral health services in long-term care (LTC) facilities is conceptualized or assessed. Objectives: This study aims to develop a model for assessing the quality of oral healthcare services in LTC facilities. Methods: This study is divided into four main steps. Firstly, I examined literature for existing concepts relating to program evaluation and quality assessment in healthcare to build a theoretical framework appropriate to dental geriatrics. Secondly, I explored as an ethnographic case study a comprehensive oral healthcare program within a single administrative group of 5 LTC facilities in a large metropolis by interviewing 33 participants, including residents and their families, nursing staff, administrators and dental personnel. I also examined policy documents and made site visits to identify other attributes influencing the quality of the program. Thirdly, I drafted the assessment model combining a theoretical framework with empirical information from the case study. And lastly, I tested the feasibility and usability of the model in another dental geriatric program in northern British Columbia. I applied the assessment model by conducting 15 interviews with participants in the program, made site-visits to the 5 facilities, and reviewed documents on the development and operation of the program. Results: A combination of theory-based evaluation and quality assurance provided six sequential and iterative steps for quality assessment of oral health services in LTC. The empirical information supported the theoretical framework that a program of oral healthcare in a LTC context should be assessed for quality from multiple perspectives; it should be comprehensive; and it should include the three main attributes of quality - capacity, performance, and outcomes. Participants revealed 20 quality indicators along with suggested program objectives which encompass eight quality dimensions such as effectiveness, efficiency, and patient-centered. Conclusion: The model provides a unique system for assessing the quality of dental services in LTC facilities that seems to meet the needs of dental and non-dental personnel in LTC.

Older adults with developmental disabilities often experience similar age-related health changes as their typically developing peers. However, they also face challenges associated with aging with a life-long disability. Because of the changes in life expectancy for people with developmental disabilities, there is a growing need for long-term residential care. The current study examines a sample of 90 counties in the state of Georgia. In addition to descriptive analysis, regression analysis was used to examine bed availability with county type (urban, rural, and metropolitan), age, race, income, education, and disability status as potential predictors. Preliminary analyses revealed that rural counties, on the whole, had more beds available than urban or metropolitan counties. However, these results were partially mediated by the following within county variables: adult disability status, income, older age, and racial makeup of the county.

The mobile telecommunication industry has experienced a very rapid growth in the recent past. This has resulted in significant technological and architectural evolution in the wireless networks. The expansion and the heterogenity of these networks have made their operational cost more and more important. Typical faults in these networks may be related to equipment breakdown and inappropriate planning and configuration. In this context, automated troubleshooting in wireless networks receives a growing importance, aiming at reducing the operational cost and providing high-quality services for the end-users. Automated troubleshooting can reduce service breakdown time for the clients, resulting in the decrease in client switchover to competing network operators. The Radio Access Network (RAN) of a wireless network constitutes its biggest part. Hence, the automated troubleshooting of RAN of the wireless networks is very important. The troubleshooting comprises the isolation of the faulty cells (fault detection), identifying the causes of the fault (fault diagnosis) and the proposal and deployement of the healing action (solution deployement). First of all, in this thesis, the previous work related to the troubleshooting of the wireless networks has been explored. It turns out that the fault detection and the diagnosis of wireless networks have been well studied in the scientific literature. Surprisingly, no significant references for the research work related to the automated healing of wireless networks have been reported. Thus, the aim of this thesis is to describe my research advances on "Automated healing of LTE wireless networks using statistical learning". We focus on the faults related to Radio Resource Management (RRM) parameters. This thesis explores the use of statistical learning for the automated healing process. In this context, the effectiveness of statistical learning for automated RRM has been investigated. This is achieved by modeling the functional relationships between the RRM parameters and Key Performance Indicators (KPIs). A generic automated RRM architecture has been proposed. This generic architecture has been used to study the application of statistical learning approach to auto-tuning and performance monitoring of the wireless networks. The use of statistical learning in the automated healing of wireless networks introduces two important diculties: Firstly, the KPI measurements obtained from the network are noisy, hence this noise can partially mask the actual behaviour of KPIs. Secondly, these automated healing algorithms are iterative. After each iteration the network performance is typically evaluated over the duration of a day with new network parameter settings. Hence, the iterative algorithms should achieve their QoS objective in a minimum number of iterations. Automated healing methodology developped in this thesis, based on statistical modeling, addresses these two issues. The automated healing algorithms developped are computationaly light and converge in a few number of iterations. This enables the implemenation of these algorithms in the Operation and Maintenance Center (OMC) in the off-line mode. The automated healing methodolgy has been applied to 3G Long Term Evolution (LTE) use cases for healing the mobility and intereference mitigation parameter settings. It has been observed that our healing objective is achieved in a few number of iterations. An automated healing process using the sequential optimization of interference mitigation and packet scheduling parameters has also been investigated. The incorporation of the a priori knowledge into the automated healing process, further reduces the number of iterations required for automated healing. Furthermore, the automated healing process becomes more robust, hence, more feasible and practical for the implementation in the wireless networks.

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4th International Conference on Advances in Experimental Structural Engineering, Ispra, Lombardy, Italy, June 29-30, 2011

Person-centred care is a holistic care approach that aims to build up and support the personhood of residents with dementia, and thereby enhance quality of life. Through a review of the literature on mealtimes in long term care homes, four main aspects of person-centred mealtime care were identified: providing food choices and preferences, supporting residents’ independence, promoting the social side of eating, and showing respect. Using a critical realist lens, this descriptive qualitative study examined current implementation of person-centred mealtime care, the influences on its implementation, and steps to more fully adopt a person-centred approach. Semi-structured interviews were conducted with 52 staff from four diverse long term care homes in southern Ontario. Participants included frontline workers, registered health care professionals, and managers. Interviews were transcribed and analysed for themes. A conceptual framework was developed through analysis of the interview data, identifying five key ways to support staff to provide person-centred care: forming a strong team, working together to provide care, enabling staff to know the residents better, equipping staff with a toolbox of strategies, and creating flexibility to optimize care. Specific strengths and areas for improvement in implementation of person-centred mealtime care were identified and explained using this conceptual framework. Elements of the framework were also applied to explain important considerations for hiring staff, educating and training staff, developing a culture of good teamwork, and involving family members and volunteers in mealtime care. / Canadian Foundation for Dietetic Research; Alzheimer Society of Canada

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