Pre-Service Teachers’ Mathematics Language and Reflection in the Context of an Early Childhood Mathematics Methods Course

Thesis (Ph.D.)--University of Washington, 2016-06

Major Depressive Disorder, Suicidal Ideation, and Suicide Attempt in Twins Discordant for Cannabis Dependence and Early-Onset Cannabis Use

Background: Previous research has reported both a moderate degree of comorbidity between cannabis dependence and major depressive disorder (MDD) and that early-onset cannabis use is associated with increased risks for MDD. Objective: To examine whether associations between both lifetime cannabis dependence and early cannabis use and measures of MDD, suicidal ideation, and suicide attempt persist after controlling for genetic and/or shared environmental influences. Design: Cross-sectional survey of twin pairs discordant for lifetime cannabis dependence and those discordant for early cannabis use. Setting: General population sample of twins (median age, 30 years). Participants: Two hundred seventy-seven same-sex twin pairs discordant for cannabis dependence and 311 pairs discordant for early-onset cannabis use (before age 17 years). Main Outcome Measures: Self-report measures of DSM-IV-defined lifetime MDD, suicidal ideation, and suicide attempt. Results: Individuals who were cannabis dependent had odds of suicidal ideation and suicide attempt that were 2.5 to 2.9 times higher than those of their non-cannabis-dependent co-twin. Additionally, cannabis dependence was associated with elevated risks of MDD in dizygotic but not in monozygotic twins. Those who initiated cannabis use before age 17 years had elevated rates of subsequent suicide attempt (odds ratio, 3.5 [95% confidence interval, 1.4-8.6]) but not of MDD or suicidal ideation. Early MDD and suicidal ideation were significantly associated with subsequent risks of cannabis dependence in discordant dizygotic pairs but not in discordant monozygotic pairs. Conclusions: Comorbidity between cannabis dependence and MDD likely arises through shared genetic and environmental vulnerabilities predisposing to both outcomes. In contrast, associations between cannabis dependence and suicidal behaviors cannot be entirely explained by common predisposing genetic and/or shared environmental predispositions. Previously reported associations between early-onset cannabis use and subsequent MDD likely reflect shared genetic and environmental vulnerabilities, although it remains possible that early-onset cannabis use may predispose to suicide attempt.

The use of cusum analysis in the early detection and management of hospital bed occupancy crises

Objective: To assess the value of cusum analysis in hospital bed management. Design: Comparative analysis of medical patient flows, bed occupancy, and emergency department admission rates and access block over 2 years. Setting: Internal Medicine Services and Emergency Department in a teaching hospital. Interventions: Improvements in bed use and changes in the level of available beds. Main outcome measures: Average length of stay; percentage occupancy of available beds; number of patients waiting more than 8 hours for admission (access block); number of medical patients occupying beds in non-medical wards; and number of elective surgical admissions. Results: Cusum analysis provided a simple means of revealing important trends in patient flows that were not obvious in conventional time-series data. This prompted improvements in bed use that resulted in a decrease of 9500 occupied bed-days over a year. Unfortunately and unexpectedly, after some initial improvement, the levels of access block, medical ward congestion and elective surgical admissions all then deteriorated significantly. This was probably caused by excessive bed closures in response to the initial improvement in bed use. Conclusion: Cusum analysis is a useful technique for the early detection of significant changes in patient flows and bed use, and in determining the appropriate number of beds required for a given rate of patient flow.

Early practical experience and the social responsiveness of clinical education: Systematic review

Objectives To find how early experience in clinical and community settings (early experience) affects medical education, and identify strengths and limitations of the available evidence. Design A systematic review rating, by consensus, the strength and importance of outcomes reported in the decade 1992-2001. Data sources Bibliographical databases and journals were searched for publications on the topic, reviewed under the auspices of the recently formed Best Evidence Medical Education (BEME) collaboration. Selection of studies All empirical studies (verifiable, observational data) were included, whatever their design, method, or language of publication. Results Early experience was most commonly provided in community settings, aiming to recruit primary care practitioners for underserved populations. It increased the popularity of primary care residencies, albeit among self selected students. It fostered self awareness and empathic attitudes towards ill people, boosted students' confidence, motivated them, gave them satisfaction, and helped them develop a professional identity. By helping develop interpersonal skills, it made entering clerkships a less stressful experience. Early experience helped students learn about professional roles and responsibilities, healthcare systems, and health needs of a population. It made biomedical, behavioural, and social sciences more relevant and easier to learn. It motivated and rewarded teachers and patients and enriched curriculums. In some countries,junior students provided preventive health care directly to underserved populations. Conclusion Early experience helps medical students learn, helps them develop appropriate attitudes towards their studies and future practice, and orientates medical curriculums towards society's needs. Experimental evidence of its benefit is unlikely to be forthcoming and yet more medical schools are likely to provide it. Effort could usefully be concentrated on evaluating the methods and outcomes of early experience provided within non-experimental research designs, and using that evaluation to improve the quality of curriculums.

A probabilistic switch model of information flow in social networks: Application for virtual circuits to organizational design

Network building and exchange of information by people within networks is crucial to the innovation process. Contrary to older models, in social networks the flow of information is noncontinuous and nonlinear. There are critical barriers to information flow that operate in a problematic manner. New models and new analytic tools are needed for these systems. This paper introduces the concept of virtual circuits and draws on recent concepts of network modelling and design to introduce a probabilistic switch theory that can be described using matrices. It can be used to model multistep information flow between people within organisational networks, to provide formal definitions of efficient and balanced networks and to describe distortion of information as it passes along human communication channels. The concept of multi-dimensional information space arises naturally from the use of matrices. The theory and the use of serial diagonal matrices have applications to organisational design and to the modelling of other systems. It is hypothesised that opinion leaders or creative individuals are more likely to emerge at information-rich nodes in networks. A mathematical definition of such nodes is developed and it does not invariably correspond with centrality as defined by early work on networks.

Acupressure for the in-patient treatment of nausea and vomiting in early pregnancy: A randomized control trial

Objective: The purpose of this study was to evaluate the efficacy of acupressure at the P6 point for the in-patient treatment of severe nausea and vomiting in early pregnancy. Study design: This was a prospective single-blind randomized control trial that involved 80 patients with nausea and vomiting plus ketonuria before 14 weeks of gestation. Results: There was no difference between length of stay, amount of medication, or fluid required between the acupressure and placebo groups, although acupressure reduced the number of patients who stayed >= 4 nights in the hospital. Acupressure was well tolerated and not associated with an increase in perinatal morbidity or death. Conclusion: The use of acupressure Lit the P6 point does not reduce the amount of antiemetric medication that is required, the requirement for intravenous fluid, and median duration of inpatient stay more than the use of placebo. A small reduction was seen in the number of women who required >= 4 days in the hospital. (c) 2006 Mosby, Inc. All rights reserved.

How can experience in clinical and community settings contribute to early medical education? A BEME systematic review

Review date: Review period January 1992-December 2001. Final analysis July 2004-January 2005. Background and review context: There has been no rigorous systematic review of the outcomes of early exposure to clinical and community settings in medical education. Objectives of review: (1) Identify published empirical evidence of the effects of early experience in medical education, analyse it, and synthesize conclusions from it. (2) Identify the strengths and limitations of the research effort to date, and identify objectives for future research. Search strategy: Ovid search of. BEI, ERIC, Medline, CIATAHL and EMBASE Additional electronic searches of: Psychinfo, Timelit, EBM reviews, SIGLE, and the Cochrane databases. Hand-searches of: Medical Education, Medical Teacher, Academic Medicine, Teaching and Learning in Medicine, Advances in Health Sciences Education, Journal of Educational Psychology. Criteria: Definitions: Experience: Authentic (real as opposed to simulated) human contact in a social or clinical context that enhances learning of health, illness and/or disease, and the role of the health professional. Early: What would traditionally have been regarded as the preclinical phase, usually the first 2 years. Inclusions: All empirical studies (verifiable, observational data) of early experience in the basic education of health professionals, whatever their design or methodology, including papers not in English. Evidence from other health care professions that could be applied to medicine was included. Exclusions: Not empirical; not early; post-basic; simulated rather than 'authentic' experience. Data collection: Careful validation of selection processes. Coding by two reviewers onto an extensively modified version of the standard BEME coding sheet. Accumulation into an Access database. Secondary coding and synthesis of an interpretation. Headline results: A total of 73 studies met the selection criteria and yielded 277 educational outcomes; 116 of those outcomes (from 38 studies) were rated strong and important enough to include in a narrative synthesis of results; 76% of those outcomes were from descriptive studies and 24% from comparative studies. Early experience motivated and satisfied students of the health professions and helped them acclimatize to clinical environments, develop professionally, interact with patients with more confidence and less stress, develop self-reflection and appraisal skill, and develop a professional identity. It strengthened their learning and made it more real and relevant to clinical practice. It helped students learn about the structure and function of the healthcare system, and about preventive care and the role of health professionals. It supported the learning of both biomedical and behavioural/social sciences and helped students acquire communication and basic clinical skills. There were outcomes for beneficiaries other than students, including teachers, patients, populations, organizations and specialties. Early experience increased recruitment to primary care/rural medical practice, though mainly in US studies which introduced it for that specific purpose as part of a complex intervention. Conclusions: Early experience helps medical students socialize to their chosen profession. It. helps them acquire a range of subject matter and makes their learning more real and relevant. It has potential benefits for other stakeholders, notably teachers and patients. It can influence career choices.

Some results on the design of field experiments for comparing unreplicated treatments

In early generation variety trials, large numbers of new breeders' lines need to be compared, and usually there is little seed available for each new line. A so-called unreplicated trial has each new line on just one plot at a site, but includes several (often around five) replicated check or control (or standard) varieties. The total proportion of check plots is usually between 10% and 20%. The aim of the trial is to choose some good performing lines (usually around 1/3 of those tested) to go on for further testing, rather than precise estimation of their mean yield. Now that spatial analyses of data from field experiments are becoming more common, there is interest in an efficient layout of an experiment given a proposed spatial analysis. Some possible design criteria are discussed, and efficient layouts under spatial dependence are considered.

Using Developmental Theories to Inform the Design of Technology for Children

Electronic Blocks are a new programming environment, designed specifically for children aged between three and eight years. As such, the design of the Electronic Block environment is firmly based on principles of developmentally appropriate practices in early childhood education. The Electronic Blocks are physical, stackable blocks that include sensor blocks, action blocks and logic blocks. Evaluation of the Electronic Blocks with both preschool and primary school children shows that the blocks' ease of use and power of engagement have created a compelling tool for the introduction of meaningful technology education in an early childhood setting. The key to the effectiveness of the Electronic Blocks lies in an adherence to theories of development and learning throughout the Electronic Blocks design process.

Accommodating intraocular lenses:a review of design concepts, usage and assessment methods

The correction of presbyopia and restoration of true accommodative function to the ageing eye is the focus of much ongoing research and clinical work. A range of accommodating intraocular lenses (AIOLs) implanted during cataract surgery has been developed and they are designed to change either their position or shape in response to ciliary muscle contraction to generate an increase in dioptric power. Two main design concepts exist. First, axial shift concepts rely on anterior axial movement of one or two optics creating accommodative ability. Second, curvature change designs are designed to provide significant amplitudes of accommodation with little physical displacement. Single-optic devices have been used most widely, although the true accommodative ability provided by forward shift of the optic appears limited and recent findings indicate that alternative factors such as flexing of the optic to alter ocular aberrations may be responsible for the enhanced near vision reported in published studies. Techniques for analysing the performance of AIOLs have not been standardised and clinical studies have reported findings using a wide range of both subjective and objective methods, making it difficult to gauge the success of these implants. There is a need for longitudinal studies using objective methods to assess long-term performance of AIOLs and to determine if true accommodation is restored by the designs available. While dual-optic and curvature change IOLs are designed to provide greater amplitudes of accommodation than is possible with single-optic devices, several of these implants are in the early stages of development and require significant further work before human use is possible. A number of challenges remain and must be addressed before the ultimate goal of restoring youthful levels of accommodation to the presbyopic eye can be achieved.

The design and piloting of an eBusiness design studio

This paper describes the establishment and early use of an eBusiness Design Studio in Aston Business School at Aston University which is located in Birmingham in the UK. It was originally conceived as an R&D aid as much as a teaching resource. However the bulk of its use to date has been in the support of Masters level modules (courses) and this description will focus on that application in the first instance. We have less experience of its use in an R&D context but we will make some preliminary comments on this in a later section.

Design and construction for traditional house building

This study is concerned with quality and productivity aspects of traditional house building. The research focuses on these issues by concentrating on the services and finishing stages of the building process. These are work stages which have not been fully investigated in previous productivity related studies. The primary objective of the research is to promote an integrated design and construction led approach to traditional house building based on an original concept of 'development cycles'. This process involves the following: site monitoring; the analysis of work operations; implementing design and construction changes founded on unique information collected during site monitoring; and subsequent re-monitoring to measure and assess Ihe effect of change. A volume house building firm has been involved in this applied research and has allowed access to its sites for production monitoring purposes. The firm also assisted in design detailing for a small group of 'experimental' production houses where various design and construction changes were implemented. Results from the collaborative research have shown certain quality and productivity improvements to be possible using this approach, albeit on a limited scale at this early experimental stage. The improvements have been possible because an improved activity sampling technique, developed for, and employed by the study, has been able to describe why many quality and productivity related problems occur during site building work. Experience derived from the research has shown the following attributes to be important: positive attitudes towards innovation; effective communication; careful planning and organisation; and good coordination and control at site level. These are all essential aspects of quality led management and determine to a large extent the overall success of this approach. Future work recommendations must include a more widespread use of innovative practices so that further design and construction modifications can be made. By doing this, productivity can be improved, cost savings made and better quality afforded.

User interface design support for the development of knowledge-based systems

The present scarcity of operational knowledge-based systems (KBS) has been attributed, in part, to an inadequate consideration shown to user interface design during development. From a human factors perspective the problem has stemmed from an overall lack of user-centred design principles. Consequently the integration of human factors principles and techniques is seen as a necessary and important precursor to ensuring the implementation of KBS which are useful to, and usable by, the end-users for whom they are intended. Focussing upon KBS work taking place within commercial and industrial environments, this research set out to assess both the extent to which human factors support was presently being utilised within development, and the future path for human factors integration. The assessment consisted of interviews conducted with a number of commercial and industrial organisations involved in KBS development; and a set of three detailed case studies of individual KBS projects. Two of the studies were carried out within a collaborative Alvey project, involving the Interdisciplinary Higher Degrees Scheme (IHD) at the University of Aston in Birmingham, BIS Applied Systems Ltd (BIS), and the British Steel Corporation. This project, which had provided the initial basis and funding for the research, was concerned with the application of KBS to the design of commercial data processing (DP) systems. The third study stemmed from involvement on a KBS project being carried out by the Technology Division of the Trustees Saving Bank Group plc. The preliminary research highlighted poor human factors integration. In particular, there was a lack of early consideration of end-user requirements definition and user-centred evaluation. Instead concentration was given to the construction of the knowledge base and prototype evaluation with the expert(s). In response to this identified problem, a set of methods was developed that was aimed at encouraging developers to consider user interface requirements early on in a project. These methods were then applied in the two further projects, and their uptake within the overall development process was monitored. Experience from the two studies demonstrated that early consideration of user interface requirements was both feasible, and instructive for guiding future development work. In particular, it was shown a user interface prototype could be used as a basis for capturing requirements at the functional (task) level, and at the interface dialogue level. Extrapolating from this experience, a KBS life-cycle model is proposed which incorporates user interface design (and within that, user evaluation) as a largely parallel, rather than subsequent, activity to knowledge base construction. Further to this, there is a discussion of several key elements which can be seen as inhibiting the integration of human factors within KBS development. These elements stem from characteristics of present KBS development practice; from constraints within the commercial and industrial development environments; and from the state of existing human factors support.

Early cognitive profiles of emergent readers:a longitudinal study

This longitudinal study examined the contribution of phonological awareness, phonological memory, and visuospatial ability to reading development in 142 English-speaking children from the start of kindergarten to the middle of Grade 2. Partial cross-lagged analyses revealed significant relationships between early performance on block design and matching letter-like forms tasks and later reading ability. Rhyme awareness correlated with later reading ability during the earliest stages, but onset awareness did not emerge as important until after the children had started reading. Digit span correlated significantly with future reading ability at every stage. These findings indicate that although phonological awareness, phonological memory, and visuospatial ability are all necessary for emergent reading, their relative importance varies across the first 2 years of reading development.

Design and analysis of distributed utility maximization algorithm for multihop wireless network with inaccurate feedback

Distributed network utility maximization (NUM) is receiving increasing interests for cross-layer optimization problems in multihop wireless networks. Traditional distributed NUM algorithms rely heavily on feedback information between different network elements, such as traffic sources and routers. Because of the distinct features of multihop wireless networks such as time-varying channels and dynamic network topology, the feedback information is usually inaccurate, which represents as a major obstacle for distributed NUM application to wireless networks. The questions to be answered include if distributed NUM algorithm can converge with inaccurate feedback and how to design effective distributed NUM algorithm for wireless networks. In this paper, we first use the infinitesimal perturbation analysis technique to provide an unbiased gradient estimation on the aggregate rate of traffic sources at the routers based on locally available information. On the basis of that, we propose a stochastic approximation algorithm to solve the distributed NUM problem with inaccurate feedback. We then prove that the proposed algorithm can converge to the optimum solution of distributed NUM with perfect feedback under certain conditions. The proposed algorithm is applied to the joint rate and media access control problem for wireless networks. Numerical results demonstrate the convergence of the proposed algorithm. © 2013 John Wiley & Sons, Ltd.