55 research outputs found
Surface-plasmon-polariton wave propagation guided by a metal slab in a sculptured nematic thin film
Surface-plasmon-polariton~(SPP) wave propagation guided by a metal slab in a
periodically nonhomogeneous sculptured nematic thin film~(SNTF) was studied
theoretically. The morphologically significant planes of the SNTF on both sides
of the metal slab could either be aligned or twisted with respect to each
other. The canonical boundary-value problem was formulated, solved for SPP-wave
propagation, and examined to determine the effect of slab thickness on the
multiplicity and the spatial profiles of SPP waves. Decrease in slab thickness
was found to result in more intense coupling of two metal/SNTF interfaces. But
when the metal slab becomes thicker, the coupling between the two interfaces
reduces and SPP waves localize to one of the two interfaces. The greater the
coupling between the two metal/SNTF interfaces, the smaller is the phase speed.Comment: 17 page
Down-Regulation of the Canonical Wnt Ξ²-Catenin Pathway in the Airway Epithelium of Healthy Smokers and Smokers with COPD
Background: The Wnt pathway mediates differentiation of epithelial tissues; depending on the tissue types, Wnt can either drive or inhibit the differentiation process. We hypothesized that key genes in the Wnt pathway are suppressed in the human airway epithelium under the stress of cigarette smoking, a stress associated with dysregulation of the epithelial differentiated state. Methodology/Principal Findings: Microarrays were used to assess the expression of Wnt-related genes in the small airway epithelium (SAE) obtained via bronchoscopy and brushing of healthy nonsmokers, healthy smokers, and smokers with COPD. Thirty-three of 56 known Wnt-related genes were expressed in the SAE. Wnt pathway downstream mediators b-catenin and the transcription factor 7-like 1 were down-regulated in healthy smokers and smokers with COPD, as were many Wnt target genes. Among the extracellular regulators that suppress the Wnt pathway, secreted frizzled-related protein 2 (SFRP2), was up-regulated 4.3-fold in healthy smokers and 4.9-fold in COPD smokers, an observation confirmed by TaqMan Real-time PCR, Western analysis and immunohistochemistry. Finally, cigarette smoke extract mediated up-regulation of SFRP2 and down-regulation of Wnt target genes in airway epithelial cells in vitro. Conclusions/Significance: Smoking down-regulates the Wnt pathway in the human airway epithelium. In the context that Wnt pathway plays an important role in differentiation of epithelial tissues, the down-regulation of Wnt pathway ma
Application of microarrays to identify and characterize genes involved in attachment dependence in HeLa cells
Variable viscosity and surface thermal capacity effects in transient natural convection flows
Transient Heat and Mass Transfer of Liquid Droplet Ignition at the Spreading over the Heated Substrate
Numerically Predicted Transient Temperature and Velocity Profiles During Natural Convection Heating of Canned Liquid Foods
A Cartesian grid generation technique for 2-D non-Newtonian blood flow through a bileaflet mechanical heart valve
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