The structure of the background errors in a global wave model.

One of the main limitations to current wave data assimilation systems is the lack of an accurate representation of the structure of the background errors. For example, the current operational wave data assimilation system at the Australian Bureau of Meteorology (BoM) prescribes globally uniform background error correlations of Gaussian shape with a length scale of 300 km and the error variance of both the background and observation errors is defined to be 0.25 m². This thesis describes an investigation into the determination of the background errors in a global wave model. There are two methods that are commonly used to determine background errors: the observational method and the 'NMC method'. The observational method is the main tool used in this thesis, although the 'NMC method' is considered also. The observational method considers correlations of the differences between observations and the background, in this case, the modelled Significant Wave Height (SWH) field. The observations used are satellite altimter estimates of SWH. Before applying the method, the effect of the irregular satellite sampling pattern is examined. This is achieved by constructing a set of anomaly correlations from modelled wave fields. The modelled wave fields are then sampled at the locations of the altimeter observations and the anomaly correlations are recalculated from the simulated altimeter data. The results are compared to the original anomaly correlations. It is found that in general, the altimeter sampling pattern underpredicts the spatial scale of the anomaly correlation. Observations of SWH from the ERS-2 altimeter are used in this thesis. To ensure that the observations used are of the highest quality possible, a validation of the European Remote Sensing Satellite 2 (ERS-2) SWH observations is performed. The altimeter data are compared to waverider buoy observations over a time period of approximately 4.5 years. With a set of 2823 co-located SWH estimates, it is found that in general, the altimeter overestimates low SWH and underestimates high SWH. A two-branched linear correction to the altimeter data is found, which reduces the overall rms error in SWH to approximately 0.2 m. Results from the previous sections are then used to calculate the background error correlations. Specifically, correlations of the differences between modelled SWH and the bias-corrected ERS-2 data are calculated. The irregular sampling pattern of the altimeter is accounted for by adjusting the correlation length scales according to latitude and the calculated length scale. The results show that the length scale of the background errors varies significantly over the globe, with the largest scales at low latitudes and shortest scales at high latitudes. Very little seasonal or year-to-year variability is detected. Conversely, the magnitude of the background error variance is found to have considerable seasonal and year-to-year variability. By separating the altimeter ground tracks into ascending and descending tracks, it is possible to examine, to a limited extent, whether any anisotropy exists in the background errors. Some of the areas on the globe that exhibit the most anisotropy are the Great Australian Bight and the North Atlantic Ocean. The background error correlations are also briefly examined via the 'NMC method', i.e., by considering differences between SWH forecasts of different ranges valid at the same time. It is found that the global distribution of the length scale of the error correlation is similar to that found using the observational method. It is also shown that the size of the correlation length scale increases as the forecast period increases. The new background error structure that has been developed is incorporated into a data assimilation system and evaluated over two month-long time periods. Compared to the current operational system at the BoM, it is found that this new structure improves the skill of the wave model by approximately 10%, with considerable geographical variability in the amount of improvement.Thesis (Ph.D.) -- University of Adelaide, School of Mathematical Sciences, 200

Photodissociation of the OD radical at 226 and 243 nm

The photodissociation dynamics of state selected OD radicals has been examined at 243 and 226 nm using velocity map imaging to probe the angle–speed distributions of theD(2S) and O(3P2) products. Both experiment and complementary first principle calculations demonstrate that photodissociation occurs by promotion of OD from high vibrational levels of the ground X 2Π state to the repulsive 1 2Σ− state

Palliative care for cirrhosis: a UK survey of health professionals' perceptions, current practice and future needs

Objective: To determine the knowledge and practice patterns of a UK cohort of relevant healthcare professionals (HCPs) about delivering palliative care in cirrhosis, and to inform priorities for future research. / Design: An on-line questionnaire survey with closed and open responses. / Setting: HCPs identified from the mailing list of special interest groups in hepatology and gastroenterology (liver), general practice and specialist palliative care (SPC) across the UK. / Results: Of the 6181 potential contacts identified, 517 HCPs responded. Most believed a role exists for SPC in caring for people with cirrhosis, but many SPC HCPs felt ill prepared to provide good care to those facing death. Further training was needed in managing liver-related symptoms, symptom control and end of life issues. All HCP groups wished to increase community provision of palliative care support, but many general practitioners felt unable to manage advanced cirrhosis in the community. There were differences in the optimal trigger for SPC referral with liver HCPs less likely to refer at symptom deterioration. Prognostication, symptom management and service configuration were key areas identified for future research. / Conclusions: All who responded acknowledged the role of SPC in caring for those dying with cirrhosis and need for further training to improve confidence and enable joint working between SPC, general practice and liver teams. Low response rates make it difficult to generalise these findings, which require further validation

"I am in other people's hands as regards my health" A sociological critique of health care encounters of people with cirrhosis. A secondary analysis

OBJECTIVES: People with cirrhosis are encouraged to participate in shared decision-making with their doctors, but studies suggest that doctors limit the amount of information that is shared. In this study we explore the presence of medical power in clinical encounters in 2015 from a patient perspective and highlight its effects on healthcare interactions. METHODS: Qualitative semi-structured interviews were conducted with ten people with cirrhosis attending a tertiary liver transplant centre in southern England. We explored their understanding of their disease and prognosis, and their participation in decision-making. Using the lens of medical power as a framework, we analysed findings into thematic sentences to summarise key ideas whilst preserving the complexity of identified concepts. RESULTS: Three key concepts explained patient perspectives of their communication with doctors: (1) portraying a positive image to doctors, (2) avoiding confrontation with doctors, (3) feeling powerless in the face of doctors' medical knowledge. These concepts show deeper dynamic issues of power during healthcare encounters, illustrated by participants' reluctance to voice their concerns and express themselves, challenge decisions, or seek information. CONCLUSION: People with cirrhosis struggle to articulate their concerns or challenge decisions on their care and treatment and may worry about potential consequences. Our findings demonstrate the continuing persistence of issues of power at play in contemporary health care

Macrostructural Analyses of Cinderella Narratives in a Large Nonclinical Sample

Purpose: Macrostructural narrative analyses are important clinical measures, revealing age-related declines and disorder-related impairments in the accuracy, completeness, logical sequencing, and organization of content. The current study aims to provide preliminary data on typical aging and psychometric evidence supporting multilevel Main Concept, Sequencing, and Story Grammar (MSSG) analyses that capture these aspects of narratives. Method: Transcripts of Cinderella narratives for 92 healthy control participants stratified across four age brackets from the online database AphasiaBank were coded by Richardson and Dalton (2016) for main concept (MC) analysis. In the current study, MSSG analyses were completed for (a) logical sequencing, independently and in combination with Mc accuracy and completeness (MC + sequencing), and (b) story grammar organization (i.e., inclusion of episodic components and complexity of episodes). Interrater agreement (99%-100%) revealed highly reliable scoring. Results: Descriptive statistics for the typically aging sample are presented for sequencing, MC + sequencing, total episodic components, and episodic complexity. Scores for participants over 60 years of age were lower (poorer) than scores for those 20-59 years of age, supporting the construct validity of score use for identifying age-related declines in performance. Conclusions: This study\u27s novel MSSG analyses of narrative production efficiently assess the logical sequencing and story grammar organization of content in healthy controls. Preliminary reliability and validity evidence support the use of all scores to measure age-related changes in narrative macrostructure. Data from this typically aging sample provide a foundation for future research and clinical assessment aimed at quantifying narrative deficits in adults with communication disorders

Women reporting sport: Still a man’s game?

While it is generally known that sports journalism is an area of gender disparity, no major academic study has established the proportion of women sports writers in the UK press. Although female sports broadcasters have increased their visibility in the United Kingdom, the same is not true in the print media. This research first examines the current visibility of women sports journalists in the national UK press, by counting by-lines according to gender. Second, a study explores if the 2012 London Olympic Games had any effect on the proportion of female sports writers in the UK press, by comparing sports by-lines in a sample 6 months before and after the games. Furthermore, these results are compared to a decade earlier to see if the situation has improved. The findings indicate that the proportion of female sports writers in the UK press is lower than in comparable countries, with little improvement over time

Main Concept, Sequencing, and Story Grammar Analyses of Cinderella Narratives in a Large Sample of Persons with Aphasia

Recently, a multilevel analytic approach called Main Concept, Sequencing, and Story Grammar (MSSG) was presented along with preliminary normative information. MSSG analyses leverage the strong psychometrics and rich procedural knowledge of both main concept analysis and story grammar component coding, complementing it with easy-to-obtain sequencing information for a rich understanding of discourse informativeness and macrostructure. This study is the next critical step for demonstrating the clinical usefulness of MSSG’s six variables (main concept composite, sequencing, main concept+sequencing, essential story grammar components, total episodic components, and episodic complexity) for persons with aphasia (PWAs). We present descriptive statistical information for MSSG variables for a large sample of PWAs and compare their performance to a large sample of persons not brain injured (PNBIs). We observed significant differences between PWAs and PNBIs for all MSSG variables. These differences occurred at the omnibus group level and for each aphasia subtype, even for PWAs with very mild impairment that is not detected with standardized aphasia assessment. Differences between PWAs and PNBIs were also practically significant, with medium to large effect sizes observed for nearly all aphasia subtypes and MSSG variables. This work deepens our understanding of discourse informativeness and macrostructure in PWAs and further develops an efficient tool for research and clinical use. Future research should investigate ways to expand MSSG analyses and to improve sensitivity and specificity

Impacts of local human activities on the Antarctic environment

We review the scientific literature, especially from the past decade, on the impacts of human activities on the Antarctic environment. A range of impacts has been identified at a variety of spatial and temporal scales. Chemical contamination and sewage disposal on the continent have been found to be long-lived. Contemporary sewage management practices at many coastal stations are insufficient to prevent local contamination but no introduction of non-indigenous organisms through this route has yet been demonstrated. Human activities, particularly construction and transport, have led to disturbances of flora and fauna. A small number of non-indigenous plant and animal species has become established, mostly on the northern Antarctic Peninsula and southern archipelagos of the Scotia Arc. There is little indication of recovery of overexploited fish stocks, and ramifications of fishing activity oil bycatch species and the ecosystem could also be far-reaching. The Antarctic Treaty System and its instruments, in particular the Convention for the Conservation of Antarctic Marine Living Resources and the Environmental Protocol, provide a framework within which management of human activities take place. In the face of the continuing expansion of human activities in Antarctica, a more effective implementation of a wide range of measures is essential, in order to ensure comprehensive protection of the Antarctic environment, including its intrinsic, wilderness and scientific values which remains a fundamental principle of the Antarctic Treaty System. These measures include effective environmental impact assessments, long-term monitoring, mitigation measures for non-indigenous species, ecosystem-based management of living resources, and increased regulation of National Antarctic Programmes and tourism activities