Second-order optical nonlinearity χ(2) is induced in glass films by corona poling. The glass films are fabricated by radio-frequency sputtering Corning7059 onto Pyrex glass substrates. The values of second-order nonlinear coefficient d33 of the corona-poled glass films are estimated to be ∼0.5 pm/V. Using the corona-poled glass films as a waveguide, phase-matched second-harmonic generation has been demonstrated in the glass films for the first time. The origin of the χ(2) is considered to be related to the defects in the glass films.

Several experiments were performed to elucidate the origin of the second-order optical nonlinearity χ(2) induced in the corona-poled Corning 7059 glass films. The values and the time decay of the second-harmonic coefficient d33 were measured for the glass films poled on several different kinds of substrates. The value of d33 was found to be dependent on the kinds of substrates. It was also observed that the glass films poled on a soda-lime substrate showed faster time decay of d33 than those poled on a Pyrex glass substrate. The glass films were also poled at room temperature, and the values of d33 were measured as a function of poling time. As a result, the value of d33 increased with the poling time and approached a value which was close to that obtained for the glass films poled at 100 °C. From the experimental results, it is speculated that the space charge formed in the vicinity of the interface between the glass film and the substrate contributes to the creation of the χ(2). The planar charge density at the glass-film–substrate interface is derived, and the experimental results are discussed.

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Novel, supramolecular, anisotropic hydrogels (called MC-PDGI gels) are presented in this study. These MC-PDGI gels consist of multi-cylindrical lipid bilayers aligned in a uniaxial manner and embedded in a soft hydrogel matrix. The bilayers and the hydrogel interact weakly due to hydrogen bonding. These MC-PDGI gels swell after exposure to water, which causes their volume and diameter to increase while simultaneously causing their length to decrease. This anisotropic swelling-induced contraction behavior is the result of competition between the isotropic elasticity of the hydrogel matrix and the interfacial tension of the lipid bilayers. Moreover, the MC-PDGI gels exhibit unique quasi one-dimensional diffusion behavior owing to the difficulty of molecular penetration through the multi-layered lipid bilayers. These materials would be useful for prolonged drug release or as an actuator.

In order to elucidate the mechanisms of breast-feeding-induced resistance to respiratory syncytial virus (RSV) infection, groups of breast-fed and bottle-fed infants with this infection were tested at the onset of illness and then again 1 and 2 weeks later for the presence of interferon (IFN) as well as of virus-specific lymphocyte transformation (LTF) activity. Alpha-IFN was detected in nine out of ten breast-fed infants, while it was found in only 11 out of 21 bottle-fed subjects. The rate of the detection of IFN was significantly higher in the former group (P less than .05). Mean levels of IFN activity were also higher in breast-fed infants than in bottle-fed subjects during the course of the illness. It was noted, however, that previous breast feeding elicited little enhancing effect on the IFN response of infants with RSV infection. Combining the two feeding groups, suppressed LTF activity to RSV seemed to be related to a positive IFN response, although the association was not statistically significant. These observations suggest that breast feeding has unique mechanisms for modulating the immune response of infants with RSV infection.