465 research outputs found

    Is Smaller Always Better? - Evaluating Video Compression Techniques for Simulation Ensembles

    Get PDF
    We provide an evaluation of the applicability of video compression techniques for compressing visualization image databases that are often used for in situ visualization. Considering relevant practical implementation aspects, we identify relevant compression parameters, and evaluate video compression for several test cases, involving several data sets and visualization methods; we use three different video codecs. To quantify the benefits and drawbacks of video compression, we employ metrics for image quality, compression rate, and performance. The experiments discussed provide insight into good choices of parameter values, working well in the considered cases

    A clinical evaluation of edge induced conjuctival staining with NewVues and SeeQuence disposable lenses

    Get PDF
    Results from a previous study indicated that the Johnson & Johnson ACUVUE® disposable lens caused more conjunctival staining than the Bausch & Lomb SEEQUENCE™ lens.l The current study was performed in the same manner as the previous study to determine if the third type of disposable lens, the Ciba NewVues®, induced a significantly different amount of conjunctival staining from the Bausch & Lomb SEEQUENCE™ lens. Sixty subjects wore a SEEQUENCEn lens on one eye, and a NewVues lens on the other. Prior to dispensing the lenses, subjects were screened by two investigators to insure no conjunctival staining was present and that lens fits were acceptable. After 24 hours, a different investigator, who did not know which lens was worn on which eye, evaluated all subjects to determine the grade of conjunctival staining and the percentage of involvement for each quadrant. Weighted averages for each quadrant and lens type were computed from the grade and percentage of involvement. These weighted averages were used in a Wilcoxin signed-rank test to determine if there was a significant difference in conjunctival staining between lens types, and in a Friedman 4-way analysis to determine if any quadrants were significantly more affected than others. These analyses determined that the NewVues lens caused less conjunctival staining than the SEEQUENCE™ lens (p\u3c0.05) and that the inferior quadrant was more affected than other quadrants (p\u3c0.05)

    Flame heights and charring on a particle board – An experimental study

    Get PDF
    Vertically oriented particle-board samples were exposed to external venting flames to study the fire spread and charring behaviour along a timber façade. Variation in flame height and the height, volume, area, density, and depth of the char layer were studied to determine the impact of heat-release rate and experiment duration. There was a peak flame height after which the flame returned to steady height approximately equal to the value before the ignition of the particle board and flame heights with inert panels. Flames did not spread to the top of the panel with increased experiment duration. Char height and area were found to increase with heat-release rate but were not affected significantly by experiment duration. Char depth and volume increased with both experiment duration and heat-release rates. Char density decreased with increased experiment duration and heat-release rate.publishedVersio

    Demographic Trends in Appalachia and Implications for Enrollments in Higher Education: The Case of Marshall University

    Get PDF
    Demographic Trends in Appalachia and Implications for Enrollments in Higher Education: The Case of Marshall University Joshua Hagen, James Leonard, and Aaron Nelson Given Appalachia’s relatively depressed economic profile and limited opportunities, especially for young adults, out-migration to other regions has long been a prominent feature of the region. More recently, declining fertility rates have contributed to create a population that increasing skews toward older age groups, both in absolute numbers and as percentages of the total. This demographic dynamic has broad implications for the socio-economic future of the region. Some of these challenges, like coping with health care costs for an increasingly elderly population, have already been much discussed, but the implications for education have received little attention. This presentation will examine recent demographic trends and future projections to gauge their probable impact on higher education enrollments in the region. Given that many of these demographic trends are most pronounced in the traditional coalfield regions of southern West Virginia and eastern Kentucky, the presentation will use Marshall University as a case study. Keywords: age demographics, higher education, population geography, West Virgini

    Towards better lumpfish: Changes in size variation, cataract development, behaviour and sea lice grazing through selective breeding

    Get PDF
    The aim of this study was to evaluate whether sea lice grazing efficiency, behaviour, size variation and cataract development can be improved through selective breeding of lumpfish. A series of studies was conducted over a four-year period where distinctive lumpfish families were established initially from wild caught mature fish and latterly from established breeding lines. Four subsequent trials (called: Phase I-IV) with ten families of lumpfish (N = 480) with a mean (± SD) weight of 46.4 ± 9.4 g (Phase I), 54.8 ± 9.2 g (Phase II), 42.0 ± 7.4 g (Phase III) and 31.3 ± 2.4 g (Phase IV) were distributed among ten sea cages (5 × 5 × 5 m) during autumn 2018 to spring 2022, each stocked with 400–404 Atlantic salmon with an average initial mean (± SD) of 387 ± 9 g (Phase I), 621 ± 15 g (Phase II), 280 ± 16 g (Phase III) and 480 ± 66 g (Phase IV). All the ten cages were stocked with 48 lumpfish (12% stocking density). In all phases there was a large inter-family variation of lice grazing of lumpfish of both L. salmonis and C. elongatus. When sea lice grazing was scaled in relation to sea lice infestation numbers on the salmon the highest sea lice grazing activity was found in Phase IV and in particular in families sired from farmed parents. There was a general trend for mean start weights and standard deviations to decrease as the phases continued. A significant increase was found in frequency of behaviour associated with feeding on natural food sources and grazing sea lice from salmon during each subsequent phase. The increase in incidence of cataracts from start to end of each trial phase was significantly reduced from Phase I (16%) to Phase IV (2%). Overall, present findings showed that sea lice grazing of both L. salmonis and C. elongatus, size variation, cataract prevalence and behaviour types can be enhanced through selection and targeted breeding programs.publishedVersio

    Lack of population genetic structure of lumpfish along the Norwegian coast: A reappraisal based on EST-STRs analyses

    Get PDF
    Lumpfish is now the single most important cleaner fish species to date and there is an extensive lumpfish translocation along the Norwegian coast. A reliable baseline information about the population genetic structure of lumpfish is a prerequisite for an optimal managing of the species to minimize possible genetic translocation and avoid possible hybridisation and introgression with local populations. The current study is a follow up of the study of Jónsdóttir et al. (2018) using expressed sequence tag-short tandem repeats (EST-STRs) markers. Samples (N = 291) were analysed from six sample locations along the Norwegian coastline from south to north, with additional 18 samples of first-generation (from wild fish) reared fish from a fish farm outside Tromsø (North Norway). Present findings show a lack of population differentiation among lumpfish sampling population along the Norwegian coast using EST-STRs, which is in accordance with the findings of Jónsdóttir et al. (2018) where genomic STRs (g-STRs) were analysed. Present findings indicate that should translocated lumpfish escape from salmon sea pens in Norway, this will probably have little impact on the genetic composition of the local lumpfish population.publishedVersio

    The IκB Function of NF-κB2 p100 Controls Stimulated Osteoclastogenesis

    Get PDF
    The prototranscription factor p100 represents an intersection of the NF-κB and IκB families, potentially serving as both the precursor for the active NF-κB subunit p52 and as an IκB capable of retaining NF-κB in the cytoplasm. NF-κB–inducing kinase (NIK) controls processing of p100 to generate p52, and thus NIK-deficient mice can be used to examine the biological effects of a failure in such processing. We demonstrate that treatment of wild-type osteoclast precursors with the osteoclastogenic cytokine receptor activator of NF-κB ligand (RANKL) increases both expression of p100 and its conversion to p52, resulting in unchanged net levels of p100. In the absence of NIK, p100 expression is increased by RANKL, but its conversion to p52 is blocked, leading to cytosolic accumulation of p100, which, acting as an IκB protein, binds NF-κB complexes and prevents their nuclear translocation. High levels of unprocessed p100 in osteoclast precursors from NIK−/− mice or a nonprocessable form of the protein in wild-type cells impair RANKL-mediated osteoclastogenesis. Conversely, p100-deficient osteoclast precursors show enhanced sensitivity to RANKL. These data demonstrate a novel, biologically relevant means of regulating NF-κB signaling, with upstream control and kinetics distinct from the classical IκBα pathway

    Genomic Signatures of Local Adaptation under High Gene Flow in Lumpfish—Implications for Broodstock Provenance Sourcing and Larval Production

    Get PDF
    Aquaculture of the lumpfish (Cyclopterus lumpus L.) has become a large, lucrative industry owing to the escalating demand for “cleaner fish” to minimise sea lice infestations in Atlantic salmon mariculture farms. We used over 10K genome-wide single nucleotide polymorphisms (SNPs) to investigate the spatial patterns of genomic variation in the lumpfish along the coast of Norway and across the North Atlantic. Moreover, we applied three genome scans for outliers and two genotype–environment association tests to assess the signatures and patterns of local adaptation under extensive gene flow. With our ‘global’ sampling regime, we found two major genetic groups of lumpfish, i.e., the western and eastern Atlantic. Regionally in Norway, we found marginal evidence of population structure, where the population genomic analysis revealed a small portion of individuals with a different genetic ancestry. Nevertheless, we found strong support for local adaption under high gene flow in the Norwegian lumpfish and identified over 380 high-confidence environment-associated loci linked to gene sets with a key role in biological processes associated with environmental pressures and embryonic development. Our results bridge population genetic/genomics studies with seascape genomics studies and will facilitate genome-enabled monitoring of the genetic impacts of escapees and allow for genetic-informed broodstock selection and management in Norway.publishedVersio

    Perturbation Expansion for Option Pricing with Stochastic Volatility

    Full text link
    We fit the volatility fluctuations of the S&P 500 index well by a Chi distribution, and the distribution of log-returns by a corresponding superposition of Gaussian distributions. The Fourier transform of this is, remarkably, of the Tsallis type. An option pricing formula is derived from the same superposition of Black-Scholes expressions. An explicit analytic formula is deduced from a perturbation expansion around a Black-Scholes formula with the mean volatility. The expansion has two parts. The first takes into account the non-Gaussian character of the stock-fluctuations and is organized by powers of the excess kurtosis, the second is contract based, and is organized by the moments of moneyness of the option. With this expansion we show that for the Dow Jones Euro Stoxx 50 option data, a Delta-hedging strategy is close to being optimal.Comment: 33 pages, 13 figures, LaTeX
    corecore