Modelling and Optimisation of Single Junction Strain Balanced Quantum Well Solar Cells

In an attempt to find the optimum number of wells for maximum conversion efficiency a pair of otherwise identical strain balanced samples, one containing 50 wells and the other 65 wells have been characterised. The 65 well sample is found to possess a lower predicted efficiency than the 50 well sample, suggesting that the optimum well number lies between these values. Devices grown using tertiary butyl arsine (TBAs) are found to possess comparable conversion efficiencies to the control cells grown using arsine and slightly superior dark IV characteristics, indicating that TBAs may be substituted for arsine without loss of device efficiency and may even be beneficial to cell performance. Several fundamental refinements to the existing quantum efficiency model of are explored. Firstly, expressions for the strained band gaps are derived. A value for the conduction band offset is . determined using the difference in energy between the heavy and light hole exciton peaks in low temperature photo current scans and found to be 0.55??0.03. The magnitude of the el-hhl exciton binding energy is also estimated from these scans and found to be in excellent agreement with the value obtained from a simple, parameterized expression for the exciton binding energy. Finally, an absolute calculation for the absorption coefficient is incorporated into the quantum efficiency model and values for the heavy and light hole in-planes masses are obtained. The model is found to underestimate the level of absorption in the intrinsic region by an amount consistent with estimates of the magnitude of the reflection from the back surface. The conversion efficiency of a sample predicted using SOL is compared to an independently obtained value. Good agreement is observed between the two results (25.3% and 25.7% for 317 suns AM1.5D). Additionally, an optimum structure for illumination by the AM1.5D spectrum was found to be a 120A well ofIno.lGaAs.Imperial Users onl

The internet: a reliable source for pregnancy and birth planning? A qualitative study

Aims and objectives: The study aims to explore why and how pregnant women use the internet as a health information source, what overall effect it has on their decision making and how this is affecting their interaction with their health care professional. Background: As the internet has become primarily a source of information among mothers-to-be, health care professionals require greater understanding of the impact of such technology to provide adequate support and advice to new mothers. Selection criteria: Pregnant women, from the time of their first meeting with their midwife until birth, were approached for the study. Supplementary criteria included: age 18 and above, living within Frimley Heath Foundation Trust, and fluency in the English language. Data collection and analysis: This was a primary research study with data collected through an online survey. As the purpose of the study was to collect data on an impact that cannot be directly observed, an online questionnaire was utilised to collect both qualitative and quantitative data. The data was analysed and presented thematically. Results: In accordance with the UK government policy to promote registration of clinical studies and public access to research findings affecting health and social care, the research is registered on the public database. Authors’ conclusion: The use of the internet as a source of pregnancy-related information has become increasingly popular and influential among childbearing women. As health professionals, midwives have a responsibility to acknowledge the fact that women access the internet for support and pregnancy-related information. For the wider profession, midwifery leaders need to set the direction of travel for their profession in engaging with social media and provide guidance on directing pregnant women towards sources of information which are both evidence-based and valid

The calcitonin gene peptide family in health and malignant disease

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Implementing peace settlements: multiple motivations, factionalism and implementation design

This research seeks to explain the obstacles to the implementation of peace settlements and to the consolidation of more co-operative and stable political systems in the aftermath of civil conflicts. Peace processes are explored through comparative observation and the theoretical modelling of strategic interactions in the immediate post-settlement implementation process. The study develops the argument that in the factionalism that characterises parties to a civil conflict, and in the multiple motivations that drive individual and group members to support these factions, he the explanations for successful, stalled or unravelled implementation processes. It further considers the proposal that the design of the implementation process, and the political economy at the regional and international level, will have a determining effect on the outcome of implementation to the extent that they impact on the intra-party struggle between factions In developing this argument a new model of implementation - the ‘mtraformation factionalism' or IFF model - is proposed The plausibility of the ‘mtraformation factionalism5 model and its predictions on the design of the implementation process are empirically explored by the application of a number of hypotheses to a dataset of 25 post-settlement civil conflicts This is supported by a further analysis of three in-depth case studies in which the institutional procedures that appear to facilitate the successful implementation of negotiated peace settlements are highlighted

The efficacy of the Teach-back Method of education on readmission rates in heart failure patients within 30 days of discharge

Background: The teach-back method is a method of education that is being used with heart failure patients in order to improve their quality of education and lower readmission rates. This literature review is aimed at synthesizing studies conducted to determine the efficacy of the teach-back method with this specific patient population. Methods: Electronic searches of CINAHL and PubMed were performed through James Madison University libraries. Articles selected for inclusion were evaluated for study design, relevance, and sample size. Results: Three studies met eligibility criteria, these studies showed statistically significant evidence that the teach-back method did reduce readmission rates in heart failure patients. Discussion: Hospital education programs should include the teach-back method in their existing education program in order to reduce readmission rates. Further studies should be done on a more diverse population and the long term results of the teach-back method. Keywords: heart failure, education, teach-back, readmission rates, discharge education, quality improvemen

The synthesis, spectroscopic and electrochemical characterisation of Ru(II) polypyridyl complexes containing hydroquinone

A range of mononuclear and dinuclear [Ru(bpy)2L]+ and [Ru(bpy)2(L)Ru(bpy)2]2+ complexes where L is 3(2’,5,-dimethoxyphenyl)-5-(pyndm-2’’-yl)-lH-r,2’,4’-tnazole, 3 (2 \ 5 ’ -dimethoxyphenyl)-5-(pyrazin-2”-yl)-1H-1’ ,25,4 ’ -tnazole, l,4-bis(5’-(pyndin-2”- yl)-1H-1’ ,2 ’ ,4’ ,-tnazol-35 -yl)-2,5-dimethoxyphenyl, l,4-bis(5’-(pyrazin-2,,-yl)-lHr ,2 ,,4,r tnazol-3’-yl)-2,5-dimethoxyphenyl and their hydroquinone and qumone analogues are reported in this thesis. Chapter one is an introductory chapter, which provides relevant background information and assists in placing the ideas and data contained in the main body of this thesis in context, while chapter two denotes the methods and procedures employed during the synthesis and characterisation of the complexes presented in the subsequent chapters. In chapter three the first group of ruthenium (II) polypyndyl complexes are described. These complexes are characterised by the presence of tnazole moieties and a dimethoxyphenyl group. These dimethoxyphenyl compounds represent model complexes for examination of the ensuing hydroquinone and qumone complexes. Synthesis of the hydroquinone and qumone complexes was also achieved via these dimethoxyphenyl counterparts. Chapter four pertains to the synthesis and charactensation of the mononuclear and dinuclear hydroquinone complexes, which differ only from the dimethoxyphenyl complexes by the presence of a dihydroxyphenyl group. These complexes exhibit behaviour comparable in a number of ways to their dimethoxy analogues except for additional redox processes in the anodic region of their cyclic voltammograms. These dihydroxyphenyl complexes also display interesting spectroelectrochemical behaviour, which was not noted in the spectra of the protected analogues, and that hence may be indicative of proton transfer between the hydroquinone and tnazole moieties. The synthesis and charactensation of the qumone complexes, which contain qumone moieties in place of the dihydroxy groups, is descnbed in chapter five. There is no quenching of the excited state noted for these complexes. All of the compounds obtained have been charactensed using [HNMR, IR, UV/Vis and emission spectroscopies both at room and low temperatures and in neutral and acidic media. The acid-base properties of each of the complexes have also been investigated in aqueous solutions. The electronic structures of the mononuclear pyndine containing qumone and hydroquinone complexes have been examined using Gausssum and DOS spectra have hence been generated in order to ascertain the nature of the HOMO and LUMO levels. In the final chapter, chapter six, a comprehensive examination of the behaviour of the range of complexes is provided and a number of observations and conclusions are proffered along with suggestions for future work. Generally, the behaviour of each of the complexes was found to differ depending both on whether the complex contained a pyrazyl or a pyndyl group and on the nature of the pendant phenyl moiety Emission, lifetime, electrochemical and spectroelectrochemical analyses of the pyrazine containing complexes suggest that switching of the excited states of these complexes from the bipyndyl moiety to the ligand occurs upon protonation of the complex. Three appendices are also provided the first of which, appendix I, contains additional NMR data Appendix II contains in-depth electrochemical studies exploring solvent conditions and identifying the optimum working-electrode Finally, appendix III compnses of additional syntheses undertaken dunng these studies, which have not been included in the mam body of the thesi

The Awakening: Empowered by water what are the personal and political implications for female activists in the Irish Anti-Water charges movement?

This research seeks to identify what are the personal and political implications for female activist in the Irish anti-water charges movement? While this movement is not a women-only organisation, nor is it concerned with gender-specific issues, the key findings in this research will demonstrate an astute and growing political awareness among women and a determined commitment to active political engagement. While this has not yet awakened any great ambition for these women to enter the structural political arena, their desire to have systematic and cultural change in Irish politics may hold the key for fuller female participation in the future. This thesis will argue that women are such a powerful resource to the anti-water charges movement; they can greatly influence and shape the organisations political goals. If the women‟s concerns and objectives are genuinely taken on board by the broader movement, there could be a popular push for a more accountable political system and culture that also facilitates women to take their place equally alongside men in Irish politics. Rather than trying to „fit‟ women into the current political system via gender-quotas, a change in system and culture, proposed and endorsed by women, may attract more able females into the Irish political arena by default. In order for the movement to embrace these concerns, it also has to organisationally demonstrate internal participatory practices and a culture that values and recognises the key contribution these women make

Temporal effects of maternal psychological distress on child mental health problems at ages 3, 5, 7 and 11: analysis from the UK Millennium Cohort Study

Background: Psychological distress is common among women of childbearing age, and limited longitudinal research suggests prolonged exposure to maternal distress is linked to child mental health problems. Estimating effects of maternal distress over time is difficult due to potential influences of child mental health problems on maternal distress and time-varying confounding by family circumstances. Methods: We analysed the UK Millennium Cohort Study, a nationally representative sample with data collected throughout childhood. Adopting a marginal structural modelling framework, we investigated effects of exposure to medium/high levels of maternal psychological distress (Kessler-6 score 8+) on child mental health problems (Strengths and Difficulties Questionnaire borderline/abnormal behaviour cut-off) using maternal and child mental health data at 3, 5, 7 and 11 years, accounting for the influence of child mental health on subsequent maternal distress, and baseline and time-varying confounding. Results: Prior and concurrent exposures to maternal distress were associated with higher levels of child mental health problems at ages 3, 5, 7 and 11 years. For example, elevated risks of child mental health problems at 11 years were associated with exposure to maternal distress from 3 years [risk ratio (RR) 1.27 (95% confidence interval (CI) 1.08–1.49)] to 11 years [RR 2.15 (95% CI 1.89–2.45)]. Prolonged exposure to maternal distress at ages 3, 5, 7 and 11 resulted in an almost fivefold increased risk of child mental health problems. Conclusions: Prior, concurrent and, particularly, prolonged exposure to maternal distress raises risks for child mental health problems. Greater support for mothers experiencing distress is likely to benefit the mental health of their children

What Could Really Excellent Civic Engagement Look Like in a Technological University?

The purpose and motivation for civic engagement in an Irish Technological University is clear, as it achieves strategic objectives at a national level for both Higher Education and community sectors. The Technological Universities Act 2018 (http://www.irishstatutebook.ie/eli/2018/act/3/enacted/en/print) defines a Technological University (TU) as having a specific focus on community and business engagement, in addition to traditional university functions of teaching, learning, and research. Even the latter were required to be relevant at regional, national, and international levels. We argue that in line with this mission, technological universities should embed deep collaboration with community partners to work towards the UN Sustainable Development Goals (SDGs) (2015 https://sustainabledevelopment.un.org/?menu=1300). This vision paper considers what excellent civic engagement in a TU could look like, if designed into structures and processes, to progress the SDGs. We draw on relevant research and our experiential knowledge as university and community organisation staff. We focus on four SDGs relevant to both the processes and content of civic engagement: quality education; reduced inequalities; sustainable cities and communities; and partnership for the goals. We draw learning from a case study of community engaged research within the curriculum to present a vision for how a TU can embed this work. We also provide recommendations to overcome critical challenges. While Ireland is our focus, our vision has international relevance too