2 resultados para Machiavelli, Niccolò, 1469-1527.

em CORA - Cork Open Research Archive - University College Cork - Ireland


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The Li-ion battery has for several years been at the forefront of powering an ever-increasing number of modem consumer electronic devices such as laptops, tablet PCs, cell phones, portable music players etc., while in more recent times, has also been sought to power a range of emerging electric and hybrid-electric vehicle classes. Given their extreme popularity, a number of features which define the performance of the Li-ion battery have become a target of improvement and have garnered tremendous research effort over the past two decades. Features such as battery capacity, voltage, lifetime, rate performance, together with important implications such as safety, environmental benignity and cost have all attracted attention. Although properties such as cell voltage and theoretical capacity are bound by the selection of electrode materials which constitute its interior, other performance makers of the Li-ion battery such as actual capacity, lifetime and rate performance may be improved by tailoring such materials with characteristics favourable to Li+ intercalation. One such tailoring route involves shrinking of the constituent electrode materials to that of the nanoscale, where the ultra-small diameters may bestow favourable Li+ intercalation properties while providing a necessary mechanical robustness during routine electrochemical operation. The work detailed in this thesis describes a range of synthetic routes taken in nanostructuring a selection of choice Li-ion positive electrode candidates, together with a review of their respective Li-ion performances. Chapter one of this thesis serves to highlight a number of key advancements which have been made and detailed in the literature over recent years pertaining to the use of nanostructured materials in Li-ion technology. Chapter two provides an overview of the experimental conditions and techniques employed in the synthesis and electrochemical characterisation of the as-prepared electrode materials constituting this doctoral thesis. Chapter three details the synthesis of small-diameter V2O5 and V2O5/TiO2 nanocomposite structures prepared by a novel carbon nanocage templating method using liquid precursors. Chapter four details a hydrothermal synthesis and characterisation of nanostructured β-LiVOPO4 powders together with an overview of their Li+ insertion properties while chapter five focuses on supercritical fluid synthesis as one technique in the tailoring of FeF2 and CoF2 powders having potentially appealing Li-ion 'conversion' properties. Finally, chapter six summarises the overall conclusions drawn from the results presented in this thesis, coupled with an indication of potential future work which may be explored upon the materials described in this work.

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Background: Self-management education may help patients with cystic fibrosis and their families to choose, monitor and adjust treatment requirements for their illness, and also to manage the effects of illness on their lives. Although self-management education interventions have been developed for cystic fibrosis, no previous systematic review of the evidence of effectiveness of these interventions has been conducted. Objectives: To assess the effects of self-management education interventions on improving health outcomes for patients with cystic fibrosis and their caregivers. Search methods: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register (date of the last search: 22 August 2013). We also searched databases through EBSCO (CINAHL; Psychological and Behavioural Sciences Collection; PsychInfo; SocINDEX) and Elsevier (Embase) and handsearched relevant journals and conference proceedings (date of the last searches: 01 February 2014 ). Selection criteria: Randomised controlled trials, quasi-randomised controlled trials or controlled clinical trials comparing different types of self-management education for cystic fibrosis or comparing self-management education with standard care or no intervention. Data collection and analysis: Two authors assessed trial eligibility and risk of bias. Three authors extracted data. Main results: Four trials (involving a total of 269 participants) were included. The participants were children with cystic fibrosis and their parents or caregivers in three trials and adults with cystic fibrosis in one trial. The trials compared four different self-management education interventions versus standard treatment: (1) a training programme for managing cystic fibrosis in general; (2) education specific to aerosol and airway clearance treatments; (3) disease-specific nutrition education; and (4) general and disease-specific nutrition education. Training children to manage cystic fibrosis in general had no statistically significant effects on weight after six to eight weeks, mean difference -7.74 lb (i.e. 3.51 kg) (95% confidence interval -35.18 to 19.70). General and disease-specific nutrition education for adults had no statistically significant effects on: pulmonary function (forced expiratory volume at one second), mean difference -5.00 % (95% confidence interval -18.10 to 8.10) at six months and mean difference -5.50 % (95% confidence interval -18.46 to 7.46) at 12 months; or weight, mean difference - 0.70 kg (95% confidence interval -6.58 to 5.18) at six months and mean difference -0.70 kg (95% confidence interval -6.62 to 5.22) at 12 months; or dietary fat intake scores, mean difference 1.60 (85% confidence interval -2.90 to 6.10) at six months and mean difference 0.20 (95% confidence interval -4.08 to 4.48) at 12 months. There is some limited evidence to suggest that self-management education may improve knowledge in patients with cystic fibrosis but not in parents or caregivers. There is also some limited evidence to suggest that self-management education may result in positively changing a small number of behaviours in both patients and caregivers. Authors' conclusions: The available evidence from this review is of insufficient quantity and quality to draw any firm conclusions about the effects of self-management education for cystic fibrosis. Further trials are needed to investigate the effects of self-management education on a range of clinical and behavioural outcomes in children, adolescents and adults with cystic fibrosis and their caregivers.