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51.
52.
Veronika Solteszova Åsmund Birkeland Sergej Stoppel Ivan Viola Stefan Bruckner 《Computer Graphics Forum》2017,36(1):249-262
Real‐time volume data acquisition poses substantial challenges for the traditional visualization pipeline where data enhancement is typically seen as a pre‐processing step. In the case of 4D ultrasound data, for instance, costly processing operations to reduce noise and to remove artefacts need to be executed for every frame. To enable the use of high‐quality filtering operations in such scenarios, we propose an output‐sensitive approach to the visualization of streaming volume data. Our method evaluates the potential contribution of all voxels to the final image, allowing us to skip expensive processing operations that have little or no effect on the visualization. As filtering operations modify the data values which may affect the visibility, our main contribution is a fast scheme to predict their maximum effect on the final image. Our approach prioritizes filtering of voxels with high contribution to the final visualization based on a maximal permissible error per pixel. With zero permissible error, the optimized filtering will yield a result that is identical to filtering of the entire volume. We provide a thorough technical evaluation of the approach and demonstrate it on several typical scenarios that require on‐the‐fly processing. 相似文献
53.
Wolf C Lederer K Pfragner R Schauenstein K Ingolic E Siegl V 《Journal of materials science. Materials in medicine》2007,18(6):1247-1252
Adding the natural antioxidant α-tocopherol to ultra-high molecular weight polyethylene (UHMW-PE) can remarkably delay the
oxidation of hip cups made thereof. However, α-tocopherol is likely to undergo different chemical transformations during manufacturing
and sterilization of hip cups than in human metabolism. Therefore, the biocompatibility of the putative transformation products
has to be investigated. In-vitro tests with L929 mice fibroblast-cells gave no evidence for cytotoxicity. To further ensure
the biocompatibility, in-vitro tests with human cells were carried out in this study. Two different human cell lines, one
adherent cell line, HF-SAR, and one suspension culture, GSJO, were tested on UHMW-PE-tablets (diameter: 15 mm; thickness:
2 mm; processed according to standard procedures for artificial hip-cups) with and without α-tocopherol with respect to cell
viability, proliferation and morphology by means of cell counting, WSt-1 proliferation assay and scanning electron microscopy.
Similar proliferation rates were found with both polyethylene samples. Further, we found intact morphology in light and electron
microscopy on each substrate. The morphologic characteristics of skin fibroblasts were not changed by any material. Normal
adherence and spreading of the fibroblasts was found on controls of glass, as well as on polystyrene and on stabilized and
unstabilized polyethylene. The characteristic behaviour as suspension of the GSJO cells remained unchanged. The mitochondrial
activity, as studied by WST-1 cell proliferation reagent, was identical on each substrate during the whole observation period
of 7 days.
Christian Wolf—in partial fulfillment of a Ph.D. (Dr.mont.) thesis at the University of Leoben 相似文献
54.
Mortality from ship emissions: a global assessment 总被引:7,自引:0,他引:7
Corbett JJ Winebrake JJ Green EH Kasibhatla P Eyring V Lauer A 《Environmental science & technology》2007,41(24):8512-8518
Epidemiological studies consistently link ambient concentrations of particulate matter (PM) to negative health impacts, including asthma, heart attacks, hospital admissions, and premature mortality. We model ambient PM concentrations from oceangoing ships using two geospatial emissions inventories and two global aerosol models. We estimate global and regional mortalities by applying ambient PM increases due to ships to cardiopulmonary and lung cancer concentration-risk functions and population models. Our results indicate that shipping-related PM emissions are responsible for approximately 60,000 cardiopulmonary and lung cancer deaths annually, with most deaths occurring near coastlines in Europe, East Asia, and South Asia. Under current regulation and with the expected growth in shipping activity, we estimate that annual mortalities could increase by 40% by 2012. 相似文献
55.
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57.
Martina Culenova Andreas Nicodemou Zuzana Varchulova Novakova Michaela Debreova Veronika Smolinsk Sona Bernatova Dana Ivanisova Olga Novotna Jaromir Vasicek Ivan Varga Stanislav Ziaran Lubos Danisovic 《International journal of molecular sciences》2021,22(22)
Mesenchymal stem cells (MSCs) represent an attractive source within the field of tissue engineering. However, their harvesting often requires invasive medical procedures. Urine-derived stem cells (UDSCs) display similar properties to MSCs, and their obtention and further processing is non-invasive for the donors as well as low cost. Here, we offer a comprehensive analysis of their biological properties. The goal of this study was to analyze their morphology, stemness, differentiation potential and cytokine profile. We have successfully isolated UDSCs from 25 urine samples. First colonies emerged up to 9 days after the initial seeding. Cell doubling time was 45 ± 0.24 SD, and when seeded at the density of 100 cells/cm2, they formed 42 ± 6.5 SD colonies within 10 days. Morphological analyzes revealed that two different types of the cell populations have been present. The first type had a rice-grain shape and the second one was characterized by a polyhedral shape. In several cell cultures, dome-shaped cells were observed as well. All examined UDSCs expressed typical MSC-like surface markers, CD73, CD90 and CD105. Moreover, conditioned media from UDSCs were harvested, and cytokine profile has been evaluated showing a significantly higher secretory rate of IL-8, IL-6 and chemokines MCP-1 and GM-CSF. We have also successfully induced human UDSCs into chondrogenic, osteogenic and myogenic cell lineages. Our findings indicate that UDSCs might have immense potential in the regeneration of the damaged tissues. 相似文献
58.
A novel approach for carotenoid analysis has been developed. Orange essential oil and juice carotenoids were separated by means of comprehensive dual-gradient elution HPLC, using normal phase with a microbore silica column in the first dimension (first D), reversed phase with a monolithic C18 column in the second dimension (second D), and a 10-port switching valve as an interface. An on-line photodiode array detector was used in order to obtain absorption spectra. Peak identification was obtained by combining retention data with the UV-visible spectra. 相似文献
59.
Physical accessibility is recognised as an important driver or factor affecting landscape development in an increasing number of studies. This work uses cost-distance methods for analysis of landscape accessibility, and presents the analysis in three historical time periods focused on the effect of accessibility on landscape development in South Slovakia. First, from periods when the cultural landscape was forming, the effect of landscape accessibility on the location of settlements is given. The variables explaining the location of historical settlements are: slope steepness, accessibility to water expressed by distance to fluvial sediments and distance within 500 m from suitable soils for agriculture. The second example is from the second half of the twentieth century, when the small-scale agricultural landscape was transformed into large-scale fields suitable for industrial agriculture. Agricultural fields located on steeper slopes and closer to settlements were more likely to survive the collectivisation of agriculture. The third example shows accessibility as a factor affecting the abandonment of the remaining traditional agricultural landscapes (TAL) as a consequence of the economic and cultural changes triggered by the transition to an open market economy. The TAL located on less accessible areas are more likely affected by the abandonment. 相似文献
60.
The regulatable MAL32 promoter in Saccharomyces cerevisiae: characteristics and tools to facilitate its use
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Matthias Meurer Veronika Chevyreva Bram Cerulus Michael Knop 《Yeast (Chichester, England)》2017,34(1):39-49
Here we describe a set of tools to facilitate the use of maltose and the MAL32 promoter for regulated gene expression in yeast, alone or in combination with the GAL1 promoter. Using fluorescent protein reporters we find that under non‐inducing conditions the MAL32 promoter exhibits a low basal level of expression, similar to the GAL1 promoter, and that both promoters can be induced independently of each other using the respective sugars, maltose and galactose. While their repression upon glucose addition is immediate and complete, we found that the MAL32 and GAL1 promoters each exhibit distinct induction kinetics. A set of plasmids is available to facilitate the application of the MAL32 promoter for chromosomal modifications using PCR targetting and for plasmid based gene expression. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献