1,993 research outputs found

    Brining Constructivity to the Classroom

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    Collecting and Analyzing Eye-Tracking Data in Outdoor Environments

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    Natural outdoor conditions pose unique obstacles for researchers, above and beyond those inherent to all mobile eye-tracking research. During analyses of a large set of eye-tracking data collected on geologists examining outdoor scenes, we have found that the nature of calibration, pupil identification, fixation detection, and gaze analysis all require procedures different from those typically used for indoor studies. Here, we discuss each of these challenges and present solutions, which together define a general method useful for investigations relying on outdoor eye-tracking data. We also discuss recommendations for improving the tools that are available, to further increase the accuracy and utility of outdoor eye-tracking data

    Maternal serum alpha-fetoprotein levels in fetal hydrocephalus: a retrospective population based study

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    BACKGROUND: Although maternal serum alpha-fetoprotein (MSAFP) is a highly sensitive marker for certain congenital malformations such as open neural tube and ventral wall defects, its usefulness as a screening test for fetal hydrocephalus is uncertain. We wished to determine the distribution of maternal serum alpha-fetoprotein levels associated with fetal hydrocephalus in a population-based screening program in Manitoba, and their potential relationship to additional anomalies. METHODS: Cases of fetal hydrocephalus unrelated to neural tube defects were ascertained from multiple sources and reviewed. Cross-reference with the Manitoba Maternal Serum Screening Program database determined which mothers had undergone maternal serum screening. Mean MSAFP levels in both isolated and complex hydrocephalus were calculated and compared with the general population of screened pregnancies using Independent Samples T-tests. RESULTS: Mean MSAFP levels in 70 cases of fetal hydrocephalus were significantly higher than those of the general population of screened pregnancies (P = 0.029). This was due to the fact that mean MSAFP levels in those cases with other major anomalies were increased over those of the general population (P = 0.041); cases with hydrocephalus alone showed no significant difference (P = 0.203). Only seven cases (10%) had MSAFP levels ≥ 2.3 multiples of the median, the cut-off used in Manitoba. However, six of these (86%) had additional major and/or minor malformations. CONCLUSION: MSAFP screening has low sensitivity for fetal hydrocephalus and is rarely elevated in isolated cases. However, when fetal hydrocephalus is detected, elevated MSAFP levels indicate that the fetus is at significant risk to have additional malformations and further investigations, including chromosome breakage studies, may be indicated

    Plasmodium-Induced Inflammation by Uric Acid

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    Infection of erythrocytes with the Plasmodium parasite causes the pathologies associated with malaria, which result in at least one million deaths annually. The rupture of infected erythrocytes triggers an inflammatory response, which is induced by parasite-derived factors that still are not fully characterized. Induced secretion of inflammatory cytokines by these factors is considered a major cause of malaria pathogenesis. In particular, the inflammatory cytokine tumor necrosis factor (TNF) is thought to mediate most of the life-threatening pathologies of the disease. Here we describe the molecular characterization of a novel pathway that results in the secretion of TNF by host cells. We found that erythrocytes infected by Plasmodium accumulate high concentrations of hypoxanthine and xanthine. Degradation of Plasmodium-derived hypoxanthine/xanthine results in the formation of uric acid, which triggers the secretion of TNF. Since uric acid is considered a “danger signal” released by dying cells to alert the immune system, Plasmodium appears to have co-evolved to exploit this warning system. Identifying the mechanisms used by the parasite to induce the host inflammatory response is essential to develop urgently needed therapies against this disease

    Identification of Vehicle Health Assurance Related Trends

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    Trend analysis in aviation as related to vehicle health management (VHM) was performed by reviewing the most current statistical and prognostics data available from the National Transportation Safety Board (NTSB) accident, the Federal Aviation Administration (FAA) incident, and the NASA Aviation Safety Reporting System (ASRS) incident datasets. In addition, future directions in aviation technology related to VHM research areas were assessed through the Commercial Aviation Safety Team (CAST) Safety Enhancements Reserved for Future Implementations (SERFIs), the National Transportation Safety Board (NTSB) Most-Wanted List and recent open safety recommendations, the National Research Council (NRC) Decadal Survey of Civil Aeronautics, and the Future Aviation Safety Team (FAST) areas of change. Future research direction in the VHM research areas is evidently strong as seen from recent research solicitations from the Naval Air Systems Command (NAVAIR), and VHM-related technologies actively being developed by aviation industry leaders, including GE, Boeing, Airbus, and UTC Aerospace Systems. Given the highly complex VHM systems, modifications can be made in the future so that the Vehicle Systems Safety Technology Project (VSST) technical challenges address inadequate maintenance crew's trainings and skills, and the certification methods of such systems as recommended by the NTSB, NRC, and FAST areas of change

    Standardising Costs or Standardising Care? Qualitative Evaluation of the Implementation and Impact of a Hospital Funding Reform in Ontario, Canada

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    Background  Since 2011, the Government of Ontario, Canada, has phased in hospital funding reforms hoping to encourage standardised, evidence-based clinical care processes to both improve patient outcomes and reduce system costs. One aspect of the reform – quality-based procedures (QBPs) – replaced some of each hospital’s global budget with a pre-set price per episode of care for patients with specific diagnoses or procedures. The QBP initiative included publication and dissemination of a handbook for each of these diagnoses or procedures, developed by an expert technical group. Each handbook was intended to guide hospitals in reducing inappropriate variation in patient care and cost by specifying an evidence-based episode of care pathway. We explored whether, how and why hospitals implemented these episode of care pathways in response to this initiative. Methods  We interviewed key informants at three levels in the healthcare system, namely individuals who conceived and designed the QBP policy, individuals and organisations supporting QBP adoption, and leaders in five case-study hospitals responsible for QBP implementation. Analysis involved an inductive approach, incorporating framework analysis to generate descriptive and explanatory themes from data. Results  The 46 key informants described variable implementation of best practice episode of care pathways across QBPs and across hospitals. Handbooks outlining evidence-based clinical pathways did not address specific barriers to change for different QBPs nor differences in hospitals’ capacity to manage change. Hospitals sometimes found it easier to focus on containing and standardising costs of care than on implementing standardised care processes that adhered to best clinical practices. Conclusion  Implementation of QBPs in Ontario’s hospitals depended on the interplay between three factors, namely complexity of changes required, internal capacity for organisational change, and availability and appropriateness of targeted external facilitators and supports to manage change. Variation in these factors across QBPs and hospitals suggests the need for more tailored and flexible implementation supports designed to fit all elements of the policy, rather than one-size-fits-all handbooks alone. Without such supports, hospitals may enact quick fixes aimed mainly at preserving budgets, rather than pursue evidence- and value-based changes in care management. Overestimating hospitals’ change management capacity increases the risk of implementation failure

    Achieving equity through 'gender autonomy': the challenges for VET policy and practice

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    This paper is based on research carried out in an EU Fifth Framework project on 'Gender and Qualification'. The research partners from five European countries investigated the impact of gender segregation in European labour markets on vocational education and training, with particular regard to competences and qualifications. The research explored the part played by gender in the vocational education and training experiences of (i) young adults entering specific occupations in child care, electrical engineering and food preparation/service (ii) adults changing occupations
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