8 research outputs found

    The size of Wiman-Valiron disks

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    Wiman-Valiron theory and results of Macintyre about "flat regions" describe the asymptotic behavior of entire functions in certain disks around points of maximum modulus. We estimate the size of these disks for Macintyre's theory from above and below.Comment: 20 page

    Minimum modulus of gap power series

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    Neopterin-induced expression of intercellular adhesion molecule-1 (ICAM-1) in type II-like alveolar epithelial cells

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    Production and release of proinflammatory mediators such as tumour necrosis factor-alpha and neopterin are common events following the activation of the cellular immune system. Concerning inflammatory disorders of the lung, e.g. sepsis or sarcoidosis, high serum neopterin levels have been reported to correlate well with the severity of the disease. These situations are often associated with an increased expression of ICAM-1 reported to be induced in type II alveolar epithelial cells. In our study we investigated the potential effects of neopterin on ICAM-1 synthesis in the type II-like pneumocyte cell line L2. Detection of ICAM-1 gene expression by reverse transcriptase-polymerase chain reaction revealed a dose-dependent effect of neopterin, with maximum impact following 12-h incubations. Comparable results were obtained when ICAM-1 protein synthesis was measured via a cell-based ELISA. In a second set of experiments we were able to show that coincubation of L2 cells with pyrrolidine dithiocarbamate (PDTC) significantly suppressed neopterin-induced ICAM-1 synthesis. Since PDTC is known to be a potent inhibitor of NF-ÎșB, the stimulating effects of neopterin on ICAM-1 gene expression and protein generation may be mediated by activation of this transcription factor. From these data we conclude that neopterin stimulates ICAM-1 production in L2 cells. In vivo, these effects may contribute to the prolongation of the inflammatory response, including cytotoxic cell host defence mechanisms that impair the functions of the airway epithelium

    From Grain to Floodplain: Evaluating heterogeneity of floodplain hydrostatigraphy using sedimentology, geophysics, and remote sensing

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    Stratigraphy is a fundamental component of floodplain heterogeneity and hydraulic conductivity and connectivity of alluvial aquifers, which affect hydrologic processes such as groundwater flow and hyporheic exchange. Watershed-scale hydrological models commonly simplify the sedimentology and stratigraphy of floodplains, neglecting natural floodplain heterogeneity and anisotropy. This study, conducted in the upper reach of the East River in the East River Basin, Colorado, USA, combines point-, meander-, and floodplain-scale data to determine key features of alluvial aquifers important for estimating hydrologic processes. We compare stratigraphy of two meanders with disparate geometries to explore floodplain heterogeneity and connectivity controls on flow and transport. Meander shape, orientation, and internal stratigraphy affected residence time estimates of laterally exchanged hyporheic water. Although the two meanders share a sediment source, vegetation, and climate, their divergent river migration histories resulted in contrasting meander hydrofacies. In turn, the extent and orientation of these elements controlled the effective hydraulic conductivity and, ultimately, estimates of groundwater transport and hyporheic residence times. Additionally, the meanders’ orientation relative to the valley gradient impacted the hydraulic gradient across the meanders—a key control of groundwater velocity. Lastly, we combine our field data with remotely sensed data and introduce a potential approach to estimate key hydrostratigraphic packages across floodplains. Prospective applications include contaminant transport studies, hyporheic models, and watershed models. © 2019 John Wiley & Sons, Ltd

    Entire and Meromorphic Functions

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