A new method was investigated to produce nanopatterns on polymeric surfaces with high resolution, good productivity, and low cost. It has certain advantages when compared with such conventional techniques as nanoimprint lithography (NIL), hot embossing, and injection molding. Polyvinyl alcohol (PVA) was utilized for preparation of the stamp with nanopatterns on its surface. The nanoimprinted PVA film was inserted into the cavity and the polymer melt was injected into the mold. Nanopatterns with pillars smaller than 100 nm were produced on the polymeric surface. The water soluble PVA film was used as the inserted template to overcome the difficulties of releasing the nanopatterned film from the substrate.

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Background and purpose: Apoptosis is a fundamental process required for neuronal development but also occurs in most of the common neurodegenerative disorders. In an attempt to obtain an anti-apoptotic neuroprotective compound from natural products, we isolated the diterpenoids, pinusolide and 15-MPA, from B. orientalis and investigated their neuroprotective activity against staurosporine (STS) -induced neuronal apoptosis. In addition, we determined the anti-apoptotic mechanism of these compounds in rat cortical cells. Experimental approach: Primary cultures of rat cortical cells injured by STS were used as an in vitro assay system. Cells were pretreated with pinusolide or 15-MPA before exposure to STS. Anti-apoptotic activities were evaluated by the measurement of cytoplasmic condensation and nuclear fragmentation. The levels of cellular peroxide, malondialdehyde (MDA) and [Ca 2 þ ] i , as well as the activities of superoxide dismutase (SOD) and caspase-3/7, were measured. Key results: Pinusolide and 15-MPA, at a concentration of 5.0 ìM, reduced the condensed nuclei and rise in [Ca 2 þ ] i that accompanies apoptosis induced by 100 nM STS. Pinusolide and 15-MPA also protected the cellular activity of SOD, an antioxidative enzyme reduced by STS insult. Furthermore, the overproduction of reactive oxygen species and lipid peroxidation induced by STS was significantly reduced in pinusolide and 15-MPA treated cells. In addition, pinusolide and 15-MPA inhibited STS-induced caspase-3/7 activation. Conclusions and Implications: These results show that pinusolide and 15-MPA protect neuronal cells from STS-induced apoptosis, probably by preventing the increase in [Ca 2 þ ] i and cellular oxidation caused by STS, and indicate that they could be used to treat neurodegenerative diseases.

Central core heating in helicon plasmas was simulated in some full wave codes considering classical collision without knowing the clear central heating mechanism since the damping rate of helicon wave was known to be low. However, collisional damping of a fast helicon wave may not be negligible when the fast wave approaches mode conversion surface (MCS) in an inhomogeneous plasma. In this study collisional damping rate of a helicon wave is estimated near MCS from the cold plasma dispersion relation. In the presence of sufficient collision, the WKBJ approximation in inhomogeneous helicon plasmas can be applied even near MCS. The collisional damping rate near MCS is found to be high enough to explain the central heating of helicon plasmas by the helicon wave itself. In this heating mechanism, high density near MCS suffices for the helicon mode and it is closely related to operating parameters such as magnetic field, driving frequency and antenna geometry.

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