A high performance dye-doped cholesteric liquid crystal (CLC) laser is demonstrated by incorporating a passive CLC reflector to the active cell. The polarization-conserved CLC reflector effectively increases the distributed feedback cavity length which, in turn, results in a significant enhancement in lasing efficiency and a dramatic reduction in beam divergence. The lasing characteristics are ...

Based on the VMS survey of the compact array antenna CA02, the effects of gravity deformation were examined in AT 39.3/115. The dominant cause of gain loss and beam distortion was identified to be the deformation of the main reflector surface with elevation. This report examines whether active displacements in the sub-reflector and/or feed might compensate for the aperture wavefront errors. All...

The transcription factor TWIST is an important factor in regulating epithelial-mesenchymal transition (EMT) and tumor metastasis. To explore the functions of TWIST in hypopharyngeal cancer, we investigated if overexpression of TWIST has an effect on FaDu cell morphology, and if alteration of TWIST has an effect on E-cadherin, N-cadherin, c-fos, MM...

The effect of D-cycloserine on the establishment of twist states in Bacillus subtilis macrofibers was examined. Macrofibers produced in the presence of the drug differed in twist compared with those produced in its absence. The degree of twist alteration was dependent on the concentration of D-cycloserine in the growth medium. Macrofibers of different twist states representative of the entire t...

Basic helix-loop-helix (bHLH) transcription factors are known as key regulators for mesenchymal differentiation. The present study showed that overexpression of Twist-1, a bHLH transcription factor, suppresses bone morphogenetic protein (BMP)-induced osteoblast differentiation, and downregulation of endogenous Twist-1 enhances BMP signaling. Maximal inhibition of BMP signaling was observed when...

BACKGROUND Epithelial-mesenchymal transition (EMT) is associated with tumor hypoxia. EMT is regulated, in part, by the action of TWIST, which inhibits of E-cadherin expression and may interfere with the p53 tumor-suppressor pathway. METHODS We examined the expression of TWIST, E-cadherin, hypoxia-inducible factor 1α (HIF1α), and p53 by immunohistochemistry in 123 cases of ovarian epithelial c...

A design criterion that permits truly omnidirectional reflectivity for all polarizations of incident light over a wide selectable range of frequencies was used in fabricating an all-dielectric omnidirectional reflector consisting of multilayer films. The reflector was simply constructed as a stack of nine alternating micrometer-thick layers of polystyrene and tellurium and demonstrates omnidire...

This paper investigates mechanisms of enhanced light absorption exhibited by ultrathin Si solar microcells integrated with a periodically nanostructured, semitransparent metallic reflector. This backside reflector comprises periodic nanoscale relief features formed by soft-imprint lithography with a thin (~35 nm) coating of Au. The work shows that microcells placed in direct contact above the n...

We report here the design of a new type of high efficiency grating coupler, based on single crystalline Si nanomembrane overlay and stacking. Such high efficiency diffractive grating couplers are designed for the purpose of coupling light between single mode fibres and nanophotonic waveguides, and for the coupling between multiple photonic interconnect layers for compact three-dimensional verti...

The far-field reflector problem is a well-known inverse problem arising in geometric optics. It consists in creating a mirror that reflects a given point light source to a prescribed target light at infinity. In this article, we study this problem under the common design constraint that the mirror is convex and is the graph of a polynomial over a given plane. We propose a method that iterativel...