123 research outputs found

    Why Nations Succeed: The Society and the State

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    The state is essential to economic development because it provides the framework within which such development can either falter or flourish. Unfortunately, much of the empirical work on the subject is very limited in scope and the theory too amorphous. The case studies usually do not analyze trends prior to the state’s colonial experience nor do they identify key variables, but rather incorporate many details without explaining their significance. This study aims to help fill these gaps by including the role of society. Utilizing China, I am able to trace the impact of the state and society upon economic development many hundreds of years prior to colonialism through a “within-case” analysis and then across cases through regression models. Ultimately, this study will hone current theories surrounding the state’s and society’s roles in economic development and provide more concrete direction for future research

    Relation of carbon dioxide in flue gases to the efficiency of a boiler

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    This thesis was undertaken to demonstrate the practical utility of measuring the efficiency of a Heine Boiler, installed in the Power Plant at the Missouri School of Mines, by the amount of COâ‚‚ in the flue gases. The tests were made on a new boiler which had recently been installed in the Power Plant. The boiler and setting being new, the tests should show a high percentage of COâ‚‚ in the flue gases and a high evaporative efficiency by the boiler --page 3

    A Man-Machine Competitive Game: A Naval Duel

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    The research reported here is the development of a man-machine game in which the competitors are the captain of a submarine and the commander of an opposing task force. This naval game has been implemented and tested in the Problem Solving Facility of the University of Pennsylvania under Contract NOnr 551(48) sponsored by the Methodology Division, Office of Naval Research. The broad objective of this research has been to experiment with and develop a man-machine framework in which an executive, scientist or engineer may employ strategies and tactics in an operational environment. A complete functional description of the game will be given in this report. This chapter provides an overview of the game and cites its salient characteristics. Chapter 2 presents the game through a play-by-play record of one competitor in an actual duel. Chapter 3 presents the various aspects of the Problem Solving methodology and developed tactics by means of three annotated duels. This also illustrates the versatility of the game and demonstrates the competitors\u27 capability to interact with the computer. Chapter 4 summarizes our research to date and lists planned refinements to the game. Additional documentation of the game structure is provided in the appendices

    The CATFISH study protocol: an evaluation of a water fluoridation scheme

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    Abstract Background Tooth decay is the commonest disease of childhood. We have known for over 90 years that fluoride can prevent tooth decay; it is present in nearly all toothpastes and can be provided in mouthwashes, gels and varnishes. The oldest method of applying fluoride is via the water supply at a concentration of 1 part per million. The two most important reviews of water fluoridation in the United Kingdom (the York Review and MRC Report on water fluoridation and health) concluded that whilst there was evidence to suggest water fluoridation provided a benefit in caries reduction, there was a need to improve the evidence base in several areas. Methods/Design This study will use a natural experiment to assess the incidence of caries in two geographical areas, one in which the water supply is returned to being fluoridated following a discontinuation of fluoridation and one that continues to have a non-fluoridated water supply. The oral health of two discrete study populations will be evaluated - those born 9 months after the water fluoridation was introduced, and those who were in their 1st year of school after the introduction of fluoridated water. Both populations will be followed prospectively for 5 years using a census approach in the exposed group along with matched numbers recruitment in a non-exposed control. Parents of the younger cohort will complete questionnaires every 6 months with child clinical examination at ages 3 and 5, whilst the older cohort will have clinical examinations only, at approximately 5, 7 and 11 years old. Discussion This project provides a unique opportunity to conduct a high quality evaluation of the reintroduction of a water fluoridation scheme, which satisfies the inclusion criteria stipulated by the York systematic review and can address the design issues identified in the MRC report. The research will make a major contribution to the understanding of the costs and effects of water fluoridation in the UK in the 21st Century. Its findings will help inform UK policy on this important public health intervention and may have a significant impact on public health policy in other developed countries. There is currently true equipoise in relation to the effectiveness of water fluoridation in contemporary populations and while the biological plausibility is well established, there is a need to examine impact on the changing epidemiological status of dental decay

    QTLs for shelf life in lettuce co-locate with those for leaf biophysical properties but not with those for leaf developmental traits

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    Developmental and biophysical leaf characteristics that influence post-harvest shelf life in lettuce, an important leafy crop, have been examined. The traits were studied using 60 informative F9 recombinant inbed lines (RILs) derived from a cross between cultivated lettuce (Lactuca sativa cv. Salinas) and wild lettuce (L. serriola acc. UC96US23). Quantitative trait loci (QTLs) for shelf life co-located most closely with those for leaf biophysical properties such as plasticity, elasticity, and breakstrength, suggesting that these are appropriate targets for molecular breeding for improved shelf life. Significant correlations were found between shelf life and leaf size, leaf weight, leaf chlorophyll content, leaf stomatal index, and epidermal cell number per leaf, indicating that these pre-harvest leaf development traits confer post-harvest properties. By studying the population in two contrasting environments in northern and southern Europe, the genotype by environment interaction effects of the QTLs relevant to leaf development and shelf life were assessed. In total, 107 QTLs, distributed on all nine linkage groups, were detected from the 29 traits. Only five QTLs were common in both environments. Several areas where many QTLs co-located (hotspots) on the genome were identified, with relatively little overlap between developmental hotspots and those relating to shelf life. However, QTLs for leaf biophysical properties (breakstrength, plasticity, and elasticity) and cell area correlated well with shelf life, confirming that the ideal ideotype lettuce should have small cells with strong cell walls. The identification of QTLs for leaf development, strength, and longevity will lead to a better understanding of processability at a genetic and cellular level, and allow the improvement of salad leaf quality through marker-assisted breeding

    Adjusting for unmeasured confounding in nonrandomized longitudinal studies: a methodological review

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    OBJECTIVE: Motivated by recent calls to use electronic health records for research, we reviewed the application and development of methods for addressing the bias from unmeasured confounding in longitudinal data. DESIGN: Methodological review of existing literature SETTING: We searched MEDLINE and EMBASE for articles addressing the threat to causal inference from unmeasured confounding in nonrandomised longitudinal health data through quasi-experimental analysis. RESULTS: Among the 121 studies included for review, 84 used instrumental variable analysis (IVA), of which 36 used lagged or historical instruments. Difference-in-differences (DiD) and fixed effects (FE) models were found in 29 studies. Five of these combined IVA with DiD or FE to try to mitigate for time-dependent confounding. Other less frequently used methods included prior event rate ratio adjustment, regression discontinuity nested within pre-post studies, propensity score calibration, perturbation analysis and negative control outcomes. CONCLUSIONS: Well-established econometric methods such as DiD and IVA are commonly used to address unmeasured confounding in non-randomised, longitudinal studies, but researchers often fail to take full advantage of available longitudinal information. A range of promising new methods have been developed, but further studies are needed to understand their relative performance in different contexts before they can be recommended for widespread use

    Overview of Noninterpretive Artificial Intelligence Models for Safety, Quality, Workflow, and Education Applications in Radiology Practice

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    Artificial intelligence has become a ubiquitous term in radiology over the past several years, and much attention has been given to applications that aid radiologists in the detection of abnormalities and diagnosis of diseases. However, there are many potential applications related to radiologic image quality, safety, and workflow improvements that present equal, if not greater, value propositions to radiology practices, insurance companies, and hospital systems. This review focuses on six major categories for artificial intelligence applications: study selection and protocoling, image acquisition, worklist prioritization, study reporting, business applications, and resident education. All of these categories can substantially affect different aspects of radiology practices and workflows. Each of these categories has different value propositions in terms of whether they could be used to increase efficiency, improve patient safety, increase revenue, or save costs. Each application is covered in depth in the context of both current and future areas of work
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