This dissertation focuses on the production of knowledge that contributes to economic growth through the accumulation of human capital and technological change. More specifically, I look at the proclivity and effectiveness of different types of universities and colleges to send individuals on to pursue a doctoral degree in science or engineering (S&E) and how PhD attainment relates to characteristics of students who attend these institutions and the faculty who teach at these institutions. A tobit estimation is employed to test for institution effects, the effect of student and faculty characteristics, and also the impact of economic factors. To partially control for selection, survey results from the Higher Education Research Institute (HERI) are used to determine students’ desire for a PhD when entering and exiting college. I find that student and faculty characteristics matter, as do economic variables. Unobservable and/or un-measureable characteristics affecting PhD output, which differ systematically by type of institution, however, remain even after controlling for the aforementioned variables. Based on the analysis in this dissertation, I conclude that much of what are typically regarded as tier effects on PhD output are in fact due to the selective matching between students and their undergraduate institutions. By adding measures for selective matching and proxies for individual opportunities, we see that ability, faculty characteristics and accomplishments, and peer effects maintain significant, positive effects on rates of PhD output. Finally, rates vary not only by institution type, but also by field.

Proof planning is a paradigm for the automation of proof that focuses on encoding intelligence to guide the proof process. The idea is to capture common patterns of reasoning which can be used to derive abstract descriptions of proofs known as proof plans. These can then be executed to provide fully formal proofs. This thesis concerns the development and analysis of a novel approach to proof planning that focuses on an explicit representation of choices during search. We embody our approach as a proof planner for the generic proof assistant Isabelle and use the Isar language, which is human-readable and machine-checkable, to represent proof plans. Within this framework we develop an inductive theorem prover as a case study of our approach to proof planning. Our prover uses the difference reduction heuristic known as rippling to automate the step cases of the inductive proofs. The development of a flexible approach to rippling that supports its various modifications and extensions is the second major focus of this thesis. Here, our inductive theorem prover provides a context in which to evaluate rippling experimentally. This work results in an efficient and powerful inductive theorem prover for Isabelle as well as proposals for further improving the efficiency of rippling. We also draw observations in order to direct further work on proof planning. Overall, we aim to make it easier for mathematical techniques, and those specific to mechanical theorem proving, to be encoded and applied to problems.

This thesis addresses the problem of generating a range of natural sounding pitch contours for speech synthesis to convey the specific meanings of different intonation patterns. Where other models can synthesise intonation adequately for short sentences, longer sentences often sound unnatural as phrasing is only really considered at the sentence level. We build models within a framework of prosodic structure derived from the linguistic analysis of a corpus of speech. We show that the use of appropriate prosodic structure allows us to produce better contours for longer sentences and allows us to capture the original style of the corpus. The resulting model is also sufficiently flexible to be adapted to suitable styles for use in other domains. To convey specific meanings we need to be able to generate different accent types. We find that the infrequency of some accent and boundary types makes them hard to model from the corpus alone. We address this issue by developing a model which allows us to isolate the parameters which control specific accent type shapes, so that we can reestimate these parameters based on other data.

The intention of most film editing is to create the impression of continuous action (“continuity”) by presenting discontinuous visual information. The techniques used to achieve this, the continuity editing rules, are well established yet there exists no understanding of their cognitive foundations. This thesis attempts to correct this oversight by proposing that “continuity” is actually what perceptual and developmental psychologists refer to as existence constancy (Michotte, 1955): “the experience that objects persist through space and time despite the fact that their presence in the visual field may be discontinuous” (Butterworth, 1991). The main conclusion of this thesis is that continuity editing ensures existence constancy by creating conditions under which a) the visual disruption created by the cut does not capture attention, b) existence constancy is assumed, and c) expectations associated with existence constancy are accommodated after the cut. Continuity editing rules are shown to identify natural periods of attention withdrawal that can be used to hide cuts. A reaction time study shows that one such period, a saccadic eye movement, occurs when an object is occluded by the screen edge. This occlusion has the potential to create existence constancy across the cut. After the cut, the object only has to appear when and where it is expected for it to be perceived as continuing to exist. This spatiotemporal information is stored in a visual index (Pylyshyn, 1989). Changes to the object’s features (stored in an object file; Kahneman, Treisman, & Gibbs, 1992), such as those caused by the cut, will go unnoticed. A duration estimation study shows that these spatiotemporal expectations distort due to the attention withdrawal. Continuity editing rules show evidence of accommodating these distortions to create perceived continuity from discontinuous visual information. The outcome of this thesis is a scientific understanding of filmic continuity. This permits filmmakers greater awareness of the perceptual consequences of their editing decisions. It also informs cognitive scientists of the potential of film as an analogue for real-world perception that exposes the assumptions, limitations, and constraints imposed upon our perception of reality.

No description available.

Background At least 111 schools and colleges of nursing across the nation provide both PhD and DNP programs (AACN, 2014a). Collaboration between nurses with doctoral preparation as researchers (PhD) and practitioners (DNP) has been recommended as essential to further the profession; that collaboration can begin during the educational process. Purpose The purpose of this paper is to describe the development and implementation of successful DNP and PhD program collaboration, and to share the results of that collaboration in an educational setting. Methods Faculty set strategic goals to maximize the effectiveness and efficiency of both new DNP and existing PhD programs. The goals were to promote collaboration and complementarity between the programs through careful capstone and dissertation differentiation, complementary residency activities, joint courses and inter-professional experiences; promote collegiality in a blended on-line learning environment through shared orientation and intensive on-campus sessions; and maximize resources in program delivery through a supportive organizational structure, equal access to technology support, and shared faculty responsibilities as appropriate to terminal degrees. Discussion Successes such as student and faculty accomplishments, and challenges such as managing class size and workload, are described. Conclusions Collaboration, collegiality and the sharing of resources have strengthened and enriched both programs and contributed to the success of students, faculty. These innovative program strategies can provide a solid foundation for DNP and PhD collaboration.

The hippocampus, in humans and rats, plays crucial roles in spatial tasks and nonspatial tasks involving episodic-type memory. This thesis presents a novel computational model of the hippocampus (CA1, CA3 and dentate gyrus) which creates a framework where spatial memory and episodic memory are explained together. This general model follows the approach where the memory function of the rodent hippocampus is seen as a “memory space” instead of a “spatial memory”. The innovations of this novel model are centred around the fact that it follows detailed hippocampal architecture constraints and uses spiking networks to represent all hippocampal subfields. This hippocampal model does not require stable attractor states to produce a robust memory system capable of pattern separation and pattern completion. In this hippocampal theory, information is represented and processed in the form of activity patterns. That is, instead of assuming firing-rate coding, this model assumes that information is coded in the activation of specific constellations of neurons. This coding mechanism, associated with the use of spiking neurons, raises many problems on how information is transferred, processed and stored in the different hippocampal subfields. This thesis explores which mechanisms are available in the hippocampus to achieve such control, and produces a detailed model which is biologically realistic and capable of explaining how several computational components can work together to produce the emergent functional properties of the hippocampus. In this hippocampal theory, precise explanations are given to why mossy fibres are important for storage but not recall, what is the functional role of the mossy cells (excitatory interneurons) in the dentate gyrus, why firing fields can be asymmetric with the firing peak closer to the end of the field, which features are used to produce “place fields”, among others. An important property of this hippocampal model is that the memory system provided by the CA3 is a palimpsest memory: after saturation, the number of patterns that can be recalled is independent of the number of patterns engraved in the recurrent network. In parallel with the development of the hippocampal computational model, a simulation environment was created. This simulation environment was tailored for the needs and assumptions of the hippocampal model and represents an important component of this thesis.

There is much interest in the study of midbrain dopaminergic (mDA) neurons as their functions include the regulation of motor function, emotion and reward pathways. Furthermore the dysfunction of these neurons is implicated in a number of human disorders such as Parkinson’s disease (PD), addiction and schizophrenia. PD is characterised by the degeneration of mDA neurons of the substantia nigra pars compacta (SNc), therefore, research into the specification and development of mDA neurons is of particular interest in relation to this disease. An understanding of the development of mDA neurons may lead to new methods of preventing their degeneration or potentially a human ES cell derived source of mDA neurons that could be used for transplantation in PD patients. Pitx3 is a bicoid-related homeodomain protein with an expression pattern restricted to the mDA neurons of the SNc and ventral tegmental area (VTA), within the central nervous system. To directly investigate a role for Pitx3 in mDA neuron development, I have analysed a line of transgenic mice with a green fluorescent protein (GFP) reporter under the control of the endogenous Pitx3 promoter. Use of the targeted GFP reporter as a midbrain dopaminergic lineage marker in the phenotypically normal heterozygous mice identified previously unrecognised ontogenetically distinct subpopulations of dopaminergic cells within the ventral midbrain. These subpopulations were detectable at E12.5 based on their temporal and topographical expression of Pitx3 and TH. Analysis of the Pitx3 null mice revealed that Pitx3 is required for the survival of a subset of nascent mDA neurons at the beginning of their terminal differentiation. The loss of mDA neurons via apoptosis continued throughout development resulting in a complete absence of SNc neurons whilst the VTA remained relatively intact in adult Pitx3 null mice. In addition, during embryonic development Pitx3 deficiency caused a loss of tyrosine hydroxylase (TH) expression specifically in the SNc dopaminergic neurons. Analysis of chimeric mice made with Pitx3 null and Pitx3 heterozygous ES cells revealed that Pitx3 acts in a cell autonomous manner. These findings point to two roles for Pitx3 in SNc mDA neurons, one in their survival and the other in regulation of TH expression. Taken together, these studies suggest that the ontogenetically distinct subpopulations may provide the molecular basis for the specific dependence of substantia nigra DA neurons on Pitx3. In addition, to establish whether the subpopulations identified at E12.5 do form the SNc and VTA, respectively, a strategy to track the fate of the earliest Pitx3- expressing cells has been initiated. In order to achieve this I have created transgenic mice in which a tamoxifen inducible form of Cre recombinase is under the control of the endogenous Pitx3 promoter. These mice can be crossed with existing mice which contain a ubiquitously expressed Cre-inducible reporter, such as LacZ or GFP, to give a temporally and spatially restricted reporter expression.

The importance of spiritual care by nurses for health and recovery has become increasingly topical in the last decade. However, there is little research into why nurses should give spiritual care. Whilst bodily caring has always been associated with nurses and nursing, spiritual care has been seen as the concern of religious ministers. The steady decline of people belonging to conventional religions in secular British society is paralleled by an upsurge of interest in spiritualities. But why nurses should give spiritual care is unclear. This qualitative, interdisciplinary study aims to explore why nurses are asked to give spiritual care to patients by considering whether there is something amiss with nursing care that would be remedied by the addition of spiritual care. To investigate this, spiritualities and bodily caring are considered in tension with each other. By using feminist standpoint epistemological approaches I propose to: a) allow the everyday experiences of nurses in giving nursing care to be expressed; b) demonstrate that themes of nursing care as comforting, compassionate caring challenge claims that the addition of spiritual care is necessary; c) show that nurses conform to the perverse body/spirit dualisms of dominant patriarchal institutions and cultural norms in describing bodily nursing care as spiritual and d) present living models of nurses and nursing care as meaningful materialist world views. Material for the study was obtained in semi-structured, one-to-one conversational interviews with eighteen experienced practising nurses. Stories of nursing care were interpreted and analysed within nursing theories of spiritual care as either imperative or integral to nursing care. Body/spirit critiques in feminist informed theologies provided a further theoretical framework for analysis. The thesis describes the everyday distress that nurses experience. The feminist design created a vehicle for fresh constructs of care by nurses not previously identified in studies of spiritual care by nurses. The findings provide an evidence base for practising nurses to validate their own skills; for managers and policy makers in planning support for nurses to give nursing care, as well as for chaplains and others to listen and respond to care matters.

Book designers and manuscript artists have inserted illustrations into narrative works for centuries now. This practice is an intelligent behaviour that requires specialised knowledge of the text and the external parameters affecting the selection and placement criteria. This thesis offers a model for automation of illustration insertion into a narrative discourse. The model presented here is a significant improvement to the crudest method of dividing the text into equal parts and inserting one illustration into each part. This study starts from the position that narratives are expressions of mental representations of a sequence of events in various modes of discourse. Here, this mental representation is referred to as ‘the story’. When coupled with a mode of discourse, the story becomes a narrative. Thus, a story can be expressed as oral, written, pictorial, or film narratives. If they all express the same sequence of events, they are telling the same story. In an illustrated narrative, while the written discourse expresses the event sequence in the form of sentences, illustrations depict them using pictorial elements. The insertion of illustration into written narrative is analogous to collating two texts into one, based on their event content. In this process, sentential representation of events are collated against the pictorial expressions of the same events. Thus, for the purposes of automation, this study claims that an investigation into the locations of events can lead to potential locations for illustration insertions. However, the list of potential illustration locations can be improved further through eliminating the events that are not depictable. This model is also able to further improve on the insertion policy by incorporating event constraints as parameters for event priorities. If a set of event types is given preference in the illustration policy, the model is able to prioritise the list accordingly. Furthermore, the model is able to allow the samedegree of customisation for preferred characters, locations, or time in the story. The prioritisation can be applied to the entire narrative, or smaller chunks of the narrative text such as chapters or sections. The model is developed via the study of the verb roots of sentences – denoting the event types – in the discourse of Mohl’s critical edition of the Shāhnāma, the Persian epic composed by Abu al Qāsium Firdausī in 400/1010. A collection of 109 illustrated manuscripts of the Shāhnāma was considered in this study. These manuscripts come from various traditions of Persian paintings and cover a long period from the early 14th century to the late 19th century. A population of nearly 6,000 Shāhnāma illustrations were annotated. Each illustration is linked to a sentence in the narrative. The bottom-up approach to the study of verb distribution in the written discourse against the illustration location distribution indicates that illustration distribution follows the same trend as that of the depictable event distribution in the discourse. Particular event tokens displayed a high rate of illustration rendering them as all time favourite events. In summary, this study claims that investigation into the distribution of events in a narrative discourse provides a model for the insertion of illustrations into a narrative work.