Research-based decision making has been advanced as a way for professionals to make a determination about the effectiveness of a potential treatment. However, informed consumers of research need to be able to determine what constitutes evidence-based practices and what criteria can be used to determine if evidence-based practices have been met. This study was a synthesis of research that involved a critical review of the empirical research studies reported in Volume 47 of the Journal of Speech, Language, and Hearing Research (JSLHR) published in 2004. This methodological research synthesis evaluated (a) the research designs used in the JSLHR studies, (b) information and rationale used to inform population validity assessment decisions, and (c) the extent to which the sampling designs, population validity rating, data analysis procedures, and the specification of generalizations and conclusions provide sufficient evidence to determine an overall rating of conclusion validity. Results indicated that less than one-fifth of the 105 research synthesis population of studies used experimental research designs. Additionally, the vast majority of the research synthesis population of studies (83.8%) were observational research designs. Only five studies out of the research synthesis population of studies (4.8%) were determined to have high population validity. In contrast, 84.8 percent of the research synthesis population of studies were found to have low population validity. That is, the studies did not contain adequate information or description of the essential sampling concerns. The vast majority or 75.3 percent of the research synthesis population of studies were rated as having low conclusion validity. Approximately one-fifth of the 105 research synthesis study population (22 studies or 20.9%) were found to have moderate conclusion validity while less than five percent of the total studies (4 of 105 studies or 3.8%) were found to have high conclusion validity. A meaningful relationship between population validity ratings and conclusion validity ratings was established. Since 81 of 105 studies have identical ratings for both population and conclusion validity, the accuracy of the prediction model developed for this study is 77.1 percent.

Since the discovery that the large-scale dynamics of galaxy clusters are dominated by dark matter, cosmologists have aspired to measure the spatial distribution of dark matter and identify its nature. Gravitational lensing, especially employing the Hubble Space Telescope (HST) has emerged as the tool-of-choice for mapping dark matter. Standing on the shoulders of the pioneering 1990's, this thesis is the first homogeneous lensing study of clusters with HST. We measure the mass and structure of an objectively-selected sample of X-ray luminous clusters at a single epoch (z ~ 0.2). We present observations often clusters (L(_x)≥8x10(^44)[0.1=2.4 keV] ergs(^-1)) and use the numerous gravitationally-lensed features in these data to constrain a detailed model of the central regions (r ~ 500 kpc) of each cluster. Our models provide an unprecedented view of cluster morphology, revealing that 60% of the sample contain significant substructure. Chandra X-ray observations confirm this is a signature of dynamical immaturity, and show that the mean temperature of the intra-cluster medium of the morphologically complex clusters is ~ 25% higher than then regular siblings. This offset results in a critical, and previously unexplored, systematic uncertainty in the use of clusters to normalise the mass power spectrum. We also use the detailed morphology of the clusters to constrain the nature of dark matter. We then exploit the clusters as gravitational telescopes, using ground-based near-infrared imaging to construct a sample of 60 gravitationally magnified Extremely Red Objects (EROs), a population that is believed to harbour important clues on the formation epoch and mechanism of massive galaxies. This unique sample overcomes the faintness of EROs (R ≥ 23, K ≥ 18) to uncover a wealth of morphological, photometric and spectroscopic evidence of diversity in both passively evolving and dusty active EROs. Coupled with our deep number counts (to K ~ 22), these observations provide important new constraints on competing theoretical models of galaxy formation.

The aim of this thesis is to investigate evidence of heating and radiative feedback in local Gould Belt star-forming regions. I discuss what impact, if any, radiative feedback is having on the star formation. I primarily use Submillimeter Common-User Bolometer Array 2 (SCUBA-2) observations from the James Clerk Maxwell Telescope (JCMT) Gould Belt legacy Survey (GBS) of nearby star-forming regions. I analyse this data in conjunction with catalogues of candidate young stellar objects (YSOcs) from mid-infrared surveys with Spitzer IRAC and MIPS surveys. I use the ratio of SCUBA-2 fluxes to calculate dust temperature, given a constant value of dust opacity spectral index, following the method of Reid & Wilson (2005). I employ a two-component beam (2CB) cross convolution to map the temperature of the Serpens MWC 297 region, achieving a resolution of 19.9′′. I employ a convolution kernel to map the temperature of the majority of the JCMT GBS, including the Aquila W40 complex, achieving a resolution of 14.8′′. I use the fellwalker clump finding algorithm to produce a global catalogue of 619 SCUBA-2 850 μm clumps across 26 distinct sub-regions of the JCMT GBS, calculating real temperatures where available. I was the PI of a proposal to observe 12CO 3-2 line emission, with the aim of decontaminating the SCUBA-2 850 μm band. I find 12CO 3-2 line contamination has a significant impact, increasing the dust temperatures calculated per pixel, on average, by 3 K where contamination is less than 10%, and by 16 K where contamination is greater than 10% (in the Aquila W40 complex). I find evidence for 12 outflows in this region, associated with active star formation. I also use archival VLA data to decontaminate both SCUBA-2 bands of free-free emission associated with massive star formation. Where compact free-free sources are sufficiently bright and optically thick, for example the B1.5Ve star MWC 297, their contribution can lead to prominent bright sources at the submillimeter wavelengths detected by SCUBA-2 and lower temperatures around Herbig stars. I present published studies of the Serpens MWC 297 region and the Aquila W40 complex. In both cases I find evidence that the presence of young OB stars is raising the temperatures of nearby clumps. Examining clumps across the JCMT GBS, I find that those clumps isolated from OB stars have a mean temperature of 15±2 K, a value that is consistent with gas temperatures (Friesen et al., 2009) and Bonnor-Ebert sphere models (Kirk et al., 2006). I find no evidence of heating from embedded low-to-medium mass YSOs. Clumps that lie within 3 pc of OB stars have a mean temperature of 21±4 K and O type stars heat clumps over the greatest range. By remodelling the heated clumps with a temperature of 15 K, I calculate that up to 10% of clumps in the JCMT GBS are no longer Jeans unstable, indicating that radiative feedback from OB stars is potentially suppressing fragmentation and allowing for the formation of more massive stars.

Various constrained frequencies of skilled model observation, under self-controlled conditions, were examined to determine whether there was an optimal frequency of modeling for learning a dance movement. Forty-eight participants with no previous dance/gymnastics experience first did a pre-test, then learned the skill over 60 interspersed observational and physical practice trials in one of four conditions that consisted of either (1) 25%, (2) 50%, (3) 75% modeling frequencies, or (4) no constraint imposed. This 60-trials acquisition phase was followed by a 24-hour post-test. Physical performance, scored by two external evaluators, revealed a significant main effect of Time from pre- to post-test (F(1, 44) = 120.43, p < .001). Cognitive representation scores revealed a main effect of Time for an image selection test (F(1, 44) = 39.09, p < .001), and a Time by Decision interaction for a forced-choice test (F(1.53, 67.48) = 7.00, p = .004). While learning was demonstrated for all measures, evidenced by higher scores at post-test than at pre-test, no main effect of Group was obtained. Consequently, the frequencies of modeling tested here under self-controlled learning conditions were equally beneficial for the learning of the novel dance skill.

While the number of techniques and procedures that surgical trainees must learn is increasing, opportunities for trainees to practice the necessary skills on patients is decreasing; the COVID-19 pandemic further limited these learning opportunities. There is a need to explore additional ways for trainees to practice and improve their performance on surgical tasks. Observing others perform tasks can improve a learner’s own performance of a task, but it is unclear how well current evidence applies to improving surgical task performance as much of the existing evidence supporting the use of observation is for non-surgical tasks. This thesis explores the influence of observing someone else demonstrate tasks on learner’s own performance of tasks relevant to surgical training. Through three experiments, we explored the influence of the type of demonstrator that a learner observes (e.g., someone who is experienced or inexperienced), and whether or not tasks that encourage the learner to think more about the quality of a demonstrator’s performance further influences the learner’s performance. The findings suggest that for learners who are new to a task, observing an experienced demonstrator is more helpful for improving performance than observing an inexperienced demonstrator. Prompting learners to think more about the quality of the demonstrator’s performance, either by requiring them to judge the demonstrator’s performance or by providing them with an expert’s judgment of the demonstrator’s performance, does not further influence the learner’s performance. The findings from this thesis provide insights into how surgical educators can optimize learner’s performance improvements on surgical tasks using observation. This thesis also provides evidence for an effective way for learners to practice surgical tasks, either in-person or remotely, before performing those tasks on patients. / Thesis / Doctor of Philosophy (PhD) / People who are training to become surgeons have a lot to learn. It is important to find ways that they can get better at tasks. We explored whether having learners watch someone else can help them get better at tasks relevant to surgery. We explored if it is better for a learner to watch someone who knows the task well or someone who is new at the task. We also explored if it is helpful for learners to think about how well the person they are watching did. We found that for learners to get better at a task, it is generally more helpful to watch someone who knows the task well. It did not help learners to think about how the person they are watching did. This helps us better understand how to help surgical learners get better at tasks from observing others before performing those tasks on patients.

The detection of a gamma-ray burst (GRB) in the solar neighborhood would have very important implications for GRB phenomenology. The leading theories for cosmological GRBs would not be able to explain such events. The final bursts of evaporating primordial black holes (PBHs), however, would be a natural explanation for local GRBs. We present a novel technique that can constrain the distance to GRBs using detections from widely separated, non-imaging spacecraft. This method can determine the actual distance to the burst if it is local. We applied this method to constrain distances to a sample of 36 short-duration GRBs detected by the Interplanetary Network (IPN) that show observational properties that are expected from PBH evaporations. These bursts have minimum possible distances in the 10(13)-10(18) cm (7-10(5) au) range, which are consistent with the expected PBH energetics and with a possible origin in the solar neighborhood, although none of the bursts can be unambiguously demonstrated to be local. Assuming that these bursts are real PBH events, we estimate lower limits on the PBH burst evaporation rate in the solar neighborhood.

Percutaneous Coronary Intervention is a common treatment for obstructive coronary artery disease, in both planned and emergency settings. Its use in the United Kingdom and elsewhere has increased dramatically in recent years due to its efficacy in the management of Acute Coronary Syndromes, increased access to PCI services, and more permissive patient selection practices. Further, a patient undergoing PCI now is likely to be treated quite differently than the same patient ten years ago, with the emergence of new interventional techniques, devices, stent types, and drugs. The widespread adoption of transradial access in favour of transfemoral access in particular has marked a new era in the delivery of PCI in the UK. Due to the rapid changes in patient and treatment characteristics, evidence generated in settings that no longer reflect the radial era is increasingly irrelevant. This thesis addresses this evidence deficit using data from the British Cardiovascular Intervention Society national PCI registry to describe contemporary trends in PCI practice and investigate the potential implications of these trends on the quality of PCI delivery. It focuses on the relationship between procedural volume, arterial access site, and short-term mortality which has not been explored in radial-era UK practice. Broadly, three research questions were posed: (1) What are the qualities and limitations of the British Cardiovascular Intervention Society PCI Registry in answering questions about routine clinical practice in the United Kingdom? (2) What is the impact on PCI outcomes of changes to the underlying patient population, changes to the selection of these patients, and changes to the treatment of these selected patients? (3) What are the consequences of these changes on the relationship of procedural volume and access site on outcomes? This thesis has showed that those centres adopting radial access more readily did not experience a decline in femoral quality, and in the most recent period were associated with better outcomes overall, particularly amongst the highest volume centres. Operator volume itself however was not associated with improved outcomes, suggesting the organisation of PCI services is not leaving operators with too few, or too many, procedures to perform competently. The current trajectory in UK practice of increasing radial adoption should continue unabated, with radial access considered as the primary access route across all clinical settings wherever possible.

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This thesis proposes a generalisation of pre-logical predicates to simply typed formal systems and their categorical models. We analyse the three elements involved in pre-logical predicates -- syntax, semantics and predicates -- within a categorical framework for typed binding syntax and semantics. We then formulate generalised pre-logical predicates and show two distinguishing properties: a) equivalence with the basic lemma and b) closure of binary pre-logical relations under relational composition. To test the adequacy of this generalisation, we derive pre-logical predicates for various calculi and their categorical models including variations of lambda calculi and non-lambda calculi such as many-sorted algebras as well as first-order logic. We then apply generalised pre-logical predicates to characterising behavioural equivalence. Examples of constructive data refinement of typed formal systems are shown, where behavioural equivalence plays a crucial role in achieving data abstraction.