1,514 research outputs found

    Print engine color management using customer image content

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    The production of quality color prints requires that color accuracy and reproducibility be maintained to within very tight tolerances when transferred to different media. Variations in the printing process commonly produce color shifts that result in poor color reproduction. The primary function of a color management system is maintaining color quality and consistency. Currently these systems are tuned in the factory by printing a large set of test color patches, measuring them, and making necessary adjustments. This time-consuming procedure should be repeated as needed once the printer leaves the factory. In this work, a color management system that compensates for print color shifts in real-time using feedback from an in-line full-width sensor is proposed. Instead of printing test patches, this novel attempt at color management utilizes the output pixels already rendered in production pages, for a continuous printer characterization. The printed pages are scanned in-line and the results are utilized to update the process by which colorimetric image content is translated into engine specific color separations (e.g. CIELAB-\u3eCMYK). The proposed system provides a means to perform automatic printer characterization, by simply printing a set of images that cover the gamut of the printer. Moreover, all of the color conversion features currently utilized in production systems (such as Gray Component Replacement, Gamut Mapping, and Color Smoothing) can be achieved with the proposed system

    Rapid response tools and datasets for post-fire modeling: linking Earth Observations and process-based hydrological models to support post-fire remediation

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    Preparation is key to utilizing Earth Observations and process-based models to support post-wildfire mitigation. Post-fire flooding and erosion can pose a serious threat to life, property and municipal water supplies. Increased runoff and sediment delivery due to the loss of surface cover and fire-induced changes in soil properties are of great concern. Remediation plans and treatments must be developed and implemented before the first major storms in order to be effective. One of the primary sources of information for making remediation decisions is a soil burn severity map derived from Earth Observation data (typically Landsat) that reflects fire induced changes in vegetation and soil properties. Slope, soils, land cover and climate are also important parameters that need to be considered. Spatially-explicit process-based models can account for these parameters, but they are currently under-utilized relative to simpler, lumped models because they are difficult to set up and require spatially-explicit inputs (digital elevation models, soils, and land cover). Our goal is to make process-based models more accessible by preparing spatial inputs before a fire, so that datasets can be rapidly combined with soil burn severity maps and formatted for model use. We are building an online database (http://geodjango.mtri.org/geowepp /) for the continental United States that will allow users to upload soil burn severity maps. The soil burn severity map is combined with land cover and soil datasets to generate the spatial model inputs needed for hydrological modeling of burn scars. Datasets will be created to support hydrological models, post-fire debris flow models and a dry ravel model. Our overall vision for this project is that advanced GIS surface erosion and mass failure prediction tools will be readily available for post-fire analysis using spatial information from a single online site

    A Novel Transgenic Rat Model of Robust Cerebral Microvascular Amyloid with Prominent Vasculopathy

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    Accumulation of fibrillar amyloid β protein in blood vessels of the brain, a condition known as cerebral amyloid angiopathy (CAA), is a common pathology of elderly individuals, a prominent comorbidity of Alzheimer disease, and a driver of vascular cognitive impairment and dementia. Although several transgenic mouse strains have been generated that develop varying levels of CAA, consistent models of associated cerebral microhemorrhage and vasculopathy observed clinically have been lacking. Reliable preclinical animal models of CAA and microhemorrhage are needed to investigate the molecular pathogenesis of this condition. Herein, we describe the generation and characterization of a novel transgenic rat (rTg-DI) that produces low levels of human familial CAA Dutch/Iowa E22Q/D23N mutant amyloid β protein in brain and faithfully recapitulates many of the pathologic aspects of human small-vessel CAA. rTg-DI rats exhibit early-onset and progressive accumulation of cerebral microvascular fibrillar amyloid accompanied by early-onset and sustained behavioral deficits. Comparable to CAA in humans, the cerebral microvascular amyloid in rTg-DI rats causes capillary structural alterations, promotes prominent perivascular neuroinflammation, and produces consistent, robust microhemorrhages and small-vessel occlusions that are readily detected by magnetic resonance imaging. The rTg-DI rats provide a new model to investigate the pathogenesis of small-vessel CAA and microhemorrhages, to develop effective biomarkers for this condition and to test therapeutic interventions

    Ozone depletion events observed in the high latitude surface layer during the TOPSE aircraft program

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    During the Tropospheric Ozone Production about the Spring Equinox (TOPSE) aircraft program, ozone depletion events (ODEs) in the high latitude surface layer were investigated using lidar and in situ instruments. Flight legs of 100 km or longer distance were flown 32 times at 30 m altitude over a variety of regions north of 58° between early February and late May 2000. ODEs were found on each flight over the Arctic Ocean but their occurrence was rare at more southern latitudes. However, large area events with depletion to over 2 km altitude in one case were found as far south as Baffin Bay and Hudson Bay and as late as 22 May. There is good evidence that these more southern events did not form in situ but were the result of export of ozone-depleted air from the surface layer of the Arctic Ocean. Surprisingly, relatively intact transport of ODEs occurred over distances of 900–2000 km and in some cases over rough terrain. Accumulation of constituents in the frozen surface over the dark winter period cannot be a strong prerequisite of ozone depletion since latitudes south of the Arctic Ocean would also experience a long dark period. Some process unique to the Arctic Ocean surface or its coastal regions remains unidentified for the release of ozone-depleting halogens. There was no correspondence between coarse surface features such as solid ice/snow, open leads, or polynyas with the occurrence of or intensity of ozone depletion over the Arctic or subarctic regions. Depletion events also occurred in the absence of long-range transport of relatively fresh “pollution” within the high latitude surface layer, at least in spring 2000. Direct measurements of halogen radicals were not made. However, the flights do provide detailed information on the vertical structure of the surface layer and, during the constant 30 m altitude legs, measurements of a variety of constituents including hydroxyl and peroxy radicals. A summary of the behavior of these constituents is made. The measurements were consistent with a source of formaldehyde from the snow/ice surface. Median NOx in the surface layer was 15 pptv or less, suggesting that surface emissions were substantially converted to reservoir constituents by 30 m altitude and that ozone production rates were small (0.15–1.5 ppbv/d) at this altitude. Peroxyacetylnitrate (PAN) was by far the major constituent of NOy in the surface layer independent of the ozone mixing ratio

    Medicinal Plants Used for the Treatment and Management of Bilharziasis and Other Parasitic Infections Affecting Humans in Zimbabwe: A Systematic Review

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    The World Health Organization (WHO) estimated that at least 251.4 million people from 78 countries were in need of preventative care for bilharziasis in 2021. Globally, soil-transmitted helminth infections are present in at least 24% of the world’s population. Tropical and subtropical areas have a wide distribution of infections with a high prevalence in the sub-Saharan Africa. The aim of this study was to document plants that have been traditionally used in Zimbabwe to manage bilharziasis and other parasitic infections. The literature review was based on published papers and abstracts retrieved from the online databases. Books, book chapters, scientific reports and theses from universities in Zimbabwe that were available online were also used in this review. Plants with the reported traditional usage against bilharziasis and other parasitic infections were recorded from the data retrieved. In total, 68 species were used to treat and manage bilharzia and other parasitic infections. Most of these medicinal plants were used to treat and manage schistosomes (fluke or worm). A total of 76.5% of the medicinal plants reported have been scientifically validated and documented to exhibit anthelmintic activity. In conclusion, Zimbabwe has a plethora of medicinal plants that can be used to manage bilharziasis and other parasitic infections

    Para a noção de transformação curricular

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    Neste artigo é evidenciada a relação entre currículo e conhecimento, abordando-se o conhecimento escolar na sua seleção, organização e transformação, a partir de uma revisão do conceito de transposição didática e da proposição dos conceitos de transformação curricular e transformação didática. Qualquer debate sobre o currículo exige a dilucidação do conhecimento e uma reflexão sobre os seus diversos significados, sobretudo quando a educação se torna num projeto amplo de questionamento da realidade social. Para além de várias questões colocadas acerca do conhecimento escolar e do modo como a sua organização pode ser realizada, procura-se centrar o debate numa reflexão sobre as fronteiras entre conhecimentos e esclarecer que, sobre essa temática, jamais poderão existir respostas fechadas.This article highlights the link between curriculum and knowledge, the approach of school knowledge’s selection, organization and transformation is based on a revision of the concept of didactic transposition and on the proposal of the concepts of curriculum and didactic transformation. Debates on curriculum demand an explanation and a reflection on the multiple meanings of knowledge mainly when education aims to be a broad project to contest social reality. It aims to focus the discussion on a reflection regarding the borders between knowledges and to show that in this subject there are never closed answers.Dans cet article est mis en évidence le rapport entre le curriculum et la connaissance, en abordant la connaissance scolaire dans sa sélection, son organisation et sa transformation à partir d’une révision du concept de transposition didactique et de la proposition des concepts de transformation du curriculum et de transformation didactique. Toute discussion sur le curriculum exige la dilucidation de la connaissance et une réflexion sur ses plusieurs signifiés, surtout quand l’éducation devient un projet plus large de mise en question de la réalité sociale. Au delà des plusieurs questions posées autour de la connaissance scolaire et de la manière comme son organisation peut être réalisée, on cherche á fixer le débat dans une réflexion sur les frontières entre connaissances et éclaircir que, sur cette thématique jamais ne pourront exister des réponses absolues.En este trabajo se pone en evidencia la relación entre el currículum y el conocimiento, abordándose el conocimiento escolar en su selección, organización y transformación desde una revisión del concepto de transposición didáctica y de la proposición de los conceptos de transformación curricular y transformación didáctica. Cualquier discusión sobre el currículum requiere la aclaración del conocimiento y una reflexión sobre sus diversos significados, especialmente cuando la educación se convierte en un proyecto más amplio de cuestionamiento de la realidad social. Además de varias preguntas sobre el conocimiento escolar y el modo en el que su organización puede tener lugar, se intenta centrar el debate en una reflexión sobre las fronteras entre conocimientos y aclarar que en esta temática jamás podrán existir respuestas cerradas.(undefined
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