Modeling Graph Languages with Grammars Extracted via Tree Decompositions

Work on probabilistic models of natural language tends to focus on strings and trees, but there is increasing interest in more general graph-shaped structures since they seem to be better suited for representing natural language semantics, ontologies, or other varieties of knowledge structures. However, while there are relatively simple approaches to defining generative models over strings and trees, it has proven more challenging for more general graphs. This paper describes a natural generalization of the n-gram to graphs, making use of Hyperedge Replacement Grammars to define generative models of graph languages.9 page(s

Molecular Characterization of the Transmission and Early Diversification of Hepatitis C Virus

Hepatitis C virus (HCV) is a medically important RNA virus in the Flaviviridae family. It persists in chronically infected individuals by replicating in hepatocytes and by evolving as a genetically diverse quasispecies that evades host immune pressures. However, transmission, with its attendant population bottlenecking, represents a period of relative vulnerability and is of particular importance with respect to viral natural history, immunopathogenesis, treatment intervention, and vaccine development. A precise molecular characterization of HCV transmission and early diversification has not previously been possible. In this dissertation work, it was hypothesized that HCV genomes that are transmitted from one individual to the next giving rise to productive clinical infection (termed transmitted/founder or T/F genomes) could be unambiguously identified by single genome sequencing (SGS), mathematical modeling, and phylogenetic inference. This hypothesis was tested in cohorts of acutely infected human subjects with community acquired HCV infection and in human-to-human and human-to-chimpanzee HCV transmission pairs. The resulting data showed that HCV transmission was generally associated with a stringent population bottleneck and that early virus evolution was characterized by diversification of discrete, low diversity sequence lineages. These findings enabled an unambiguous phylogenetic inference of T/F genomes, a precise characterization of early molecular pathways of viral sequence evolution, and a refined estimate of the in vivo mutation rate of HCV, which was at least 5-fold lower than previously reported. These efforts further allowed for the molecular identification, cloning, and analysis of full-length T/F viral genomes, which like most HCV clones, were restricted in their in vitro replication capacity. Altogether, our findings provide a substantially enhanced molecular view of HCV transmission and early diversification in natural human infection and illustrate a novel experimental approach to the proteome-wide analysis of HCV that may aid future vaccine development efforts

Semantic Parsing with Bayesian Tree Transducers

Many semantic parsing models use tree transformations to map between natural language and meaning representation. However, while tree transformations are central to several state-of-the-art approaches, little use has been made of the rich literature on tree automata. This paper makes the connection concrete with a tree transducer based semantic parsing model and suggests that other models can be interpreted in a similar framework, increasing the generality of their contributions. In particular, this paper further introduces a variational Bayesian inference algorithm that is applicable to a wide class of tree transducers, producing state-of-the-art semantic parsing results while remaining applicable to any domain employing probabilistic tree transducers.9 page(s

The main course was mealworms: the epistemics of art and science in public engagement

The authors share an emerging analytical approach to designing and studying STEAM programs that focuses on how programs integrate the respective epistemic practices—the ways in which knowledge is constructed—of science and art. They share the rationale for moving beyond surface features of STEAM programs (e.g. putting textiles and electronics on the same table) to the discipline-specific ways in which  participants engage in creative inquiry and production. They share a brief example from a public STEAM event to demonstrate the ways in which this approach can foster reflection and intentionality in the design and implementation of STEAM programs

The Determinants of Privatised Enterprise Performance in Russia

Using data from a large enterprise-level panel designed to address this issue, we account for enterprise performance in Russia. We link performance to four aspects of the economic environment: enterprise ownership; corporate governance; market structures and competition; and financial constraints. We conclude that private ownership and improved performance are not correlated, though restructuring is positively associated with the competitiveness of the market environment. These findings on private ownership support those of previous studies, e.g. Earle and Estrin (1997). Moreover, we find evidence that financially unconstrained firms are better in their undertaking of restructuring measures then financially constrained firms. Further analysis suggests that causality runs from restructuring to financial constraint, rather than the reverse. Finally, our findings indicate strong complementarities between the four factors influencing improved company performance, confirming the view that these factors need to be considered jointly.Privatisation, enterprise performance, competition, corporate governance, investment

Financial characteristics of the nonprofit organisation: theory and evidence for the assessment of the financial condition of South African public universities

In this thesis, an analytical framework is developed for the assessment of the financial condition of South African public universities. Foundational constructs of nonprofit economics are applied in the consideration of financial theories of nonprofit organisations in general, and public universities in particular. From this review, a number of hypotheses are developed. Each of these specifies a positive or negative association between a university's financial condition and a particular dimension of its assets, liabilities, equity, revenues, expenses and surplus. From the nonprofit financial analysis literature, ratios and indicators relevant to these hypotheses are selected. Audited data from the annual financial statements of the universities for the seven year period 2007 to 2013 are substantially transformed in mitigation of failures in accounting, auditing and accountability. The adjusted accounting numbers are used to calculate the financial indicators applicable to each university. Exploratory factor analysis is implemented to categorise and organise this large indicator set on the basis of identified associations with a smaller number of factors. It is found that the financial condition of South African public universities is defined by two broad financial characteristics, capital and revenue. Assessment of the capital dimension is informed by a focus on institutional equity, with particular emphasis on expendable equity and its proportionate relationships with surplus, total capital, and total expenses. The revenue dimension is appropriately evaluated in the context of a comparative and interactive consideration of the three main components of South African public university revenue, as well as the proportionate relationship between non-staff operating expenses and total expenses. The framework displays considerable levels of stability and consistency over the seven year review period, and its constructs are, in addition, robust to the application of multiple alternative confirmatory tests involving financial data that are independent of the factor solutions. The financial condition assessment framework developed in this thesis offers a contribution to a broader discourse in nonprofit finance and accounting, with a focus on public university finances

Experiencing dialysis : a descriptive phenomenological study of nurses and patients in dialysis satellite units

Experiencing Dialysis: A Descriptive Phenomenological Study of Nurses and Patients in Dialysis Satellite Units Dialysis satellite units (DSU) have been a method of treatment delivery in the UK since the 1980s. Units were developed to expand dialysis provision and serve a number of patients from specific geographical areas. There is a dearth of research related to satellite unit dialysis. Most research related to haemodialysis usually incorporates satellite unit patients in their findings. Available research is related to measurable parameters of medical treatment. At the start of the research there was no research related to nursing experience on satellite units. Nursing experience was examined generally and specifically around aspects such as stress. Research relating to patient experience is based upon methodologically accepted approaches such as measuring stress, coping, compliance and quality of life. These methods frequently reduce experience into statistics that, while they have a range of application, often miss the depth of meaning related to experience. Patients express a great deal of satisfaction about their experiences of satellite units and are reluctant to return to a main unit for treatment. This expression of experience stimulated the research question ‘What is the experience of patients and nurses in dialysis satellite units?’ The research aims to examine the subjective experience of both nurses and patients. The research will aim to describe structures of experience to shed light upon expressions of satisfaction and reluctance. The means for examining subjective experience required the use of a qualitative research method. The descriptive phenomenology of Husserl was chosen for its distinct structure and theory free approach to studying phenomena of the Lifeworld. The method of data collection was provided by a novel phenomenological interview structure which incorporated the use of imaginative variation. Observation as a method of data collection was also used because it provided aspects of experience that would remain hidden through interview method alone. Spradley’s (1980) descriptive matrix was used to guide observations. A combination of both methods increases phenomenological adequacy. Three DSUs provided the field of study. A total of twenty five patients and twelve staff members were interviewed. Ethical approval was obtained for the research. 5 Data analysis was undertaken with a modified version of Giorgi’s (1985) phenomenological method of data reduction by meaning units and generalization. Imaginative variation was applied for structural clarity and structural coding was applied for adequacy. Four general structures of experience were synthesised to provide a constitution of phenomena. 1. Experiencing Illness. Illness is context structure that gives meaning to dialysis. Minimalization of illness is structured through the absence of doctors, not seeing illness and distancing illness by referral to the main unit. 2. Time Saved. Time is saved for the patient through fewer patients for dialysis, time distraction, and absence of illness. Staff save time through preparation and planning and making time available for patients. 3. Feeling Safe: Repetition, routine, familiarity, predictability, nearness and closeness, being known, knowing others and not thinking of illness all provide an experience structure of feeling safe. 4. Freedom to Practice: Making a difference. Feeling isolated and an awareness of responsibility leads to decision thoughtfulness. Thoughtfulness enhances decision making giving a sense of autonomy, confidence and freedom to practice. These facets of experience enable nurses to make a difference to patient care. The findings of the research identify the patient desire to avoid experiencing illness improves coping ability. Satellite unit nurses develop enhanced skills and expertise that enables quality patient care. The experience of nurses is congruent with other nurse-led units. Implications for practice are the development of autonomy and responsibility which would enhance service provision for patients. An innovative application of phenomenology involving observation and imaginative variation can produce accurate descriptions of structure of experience.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Computerized clinical decision support for the early recognition and management of acute kidney injury: a qualitative evaluation of end-user experience

Background - Although the efficacy of computerized clinical decision support (CCDS) for acute kidney injury (AKI) remains unclear, the wider literature includes examples of limited acceptability and equivocal benefit. Our single-centre study aimed to identify factors promoting or inhibiting use of in-patient AKI CCDS. Methods - Targeting medical users, CCDS triggered with a serum creatinine rise of ≥25 μmol/L/day and linked to guidance and test ordering. User experience was evaluated through retrospective interviews, conducted and analysed according to Normalization Process Theory. Initial pilot ward experience allowed tool refinement. Assessments continued following CCDS activation across all adult, non-critical care wards. Results - Thematic saturation was achieved with 24 interviews. The alert was accepted as a potentially useful prompt to early clinical re-assessment by many trainees. Senior staff were more sceptical, tending to view it as a hindrance. ‘Pop-ups’ and mandated engagement before alert dismissal were universally unpopular due to workflow disruption. Users were driven to close out of the alert as soon as possible to review historical creatinines and to continue with the intended workflow. Conclusions - Our study revealed themes similar to those previously described in non-AKI settings. Systems intruding on workflow, particularly involving complex interactions, may be unsustainable even if there has been a positive impact on care. The optimal balance between intrusion and clinical benefit of AKI CCDS requires further evaluation

Minimum acceptable place standards

Minimum acceptable place standard