Dynamic stills and clip trailers

We propose a method for generating visual summaries of video. It reduces browsing time, minimizes screen-space utilization, while preserving the crux of the video content and the sensation of motion. The outputs are images or short clips, denoted as dynamic stills or clip trailers, respectively. The method selects informative poses out of extracted video objects. Optimal rotations and transparency supports visualization of an increased number of poses, leading to concise activity visualization. Our method addresses previously avoided scenarios, e.g., activities occurring in one place, or scenes with non-static background. We demonstrate and evaluate the method for various types of videos.     

Crystallization behavior and viscoelasticity of bamboo‐fiber composites

This article deals with the effect of the kneading temperature on the crystallization of a matrix polymer and the viscoelasticity of a bamboo‐fiber‐reinforced biodegradable polymer composite. Upon the investigation of poly(butylene succinate) after melt mixing, spherulite generation was observed with polarized light microscopy and differential scanning calorimetry measurements. An increase in the spherulite dimensions was observed at high kneading temperatures (>150°C) in both the neat polymer and the bamboo‐fiber composite. Spherulite growth was initiated from the bulk matrix polymer and not from the surface of the bamboo fibers. The kneading temperature influenced the melt viscoelasticity above the melting point of poly(butylene succinate) but did not influence the viscoelasticity below the melting point. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 603–612, 2005     

Fabrication of diffractive optical elements inside polymers by femtosecond laser irradiation

Bragg-type gratings were prepared by irradiation inside a series of optical polymers with femtosecond laser pulses and the preparation conditions of the grating were examined. Repeated scanning irradiation with femtosecond laser pulses formed gratings due to refractive index changes inside polymers. Among the polymers examined in the present study, polymethylpentene (PMP) showed the highest diffraction efficiency, which was an order of magnitude higher than those of other optical polymers. The density of PMP was the lowest among the polymers evaluated in the present study, and the large volume contraction based on its low density was responsible for the larger refractive index change of PMP. Furthermore, we fabricated large-area diffractive optical elements (DOEs) in PMP measuring 15 × 25 mm² by widening the scanning area.     

Performance simulation of solar-boosted ocean thermal energy conversion plant

Ocean thermal energy conversion (OTEC) is a power generation method that utilizes small temperature difference between the warm surface water and cold deep water of the ocean. This paper describes the performance simulation results of an OTEC plant that utilizes not only ocean thermal energy but also solar thermal energy as a heat source. This power generation system was termed SOTEC (solar-boosted ocean thermal energy conversion). In SOTEC, the temperature of warm sea water was boosted by using a typical low-cost solar thermal collector. In order to estimate the potential thermal efficiency and required effective area of a solar collector for a 100-kWe SOTEC plant, first-order modeling and simulation were carried out under the ambient conditions at Kumejima Island in southern part of Japan. The results show that the proposed SOTEC plant can potentially enhance the annual mean net thermal efficiency up to a value that is approximately 1.5 times higher than that of the conventional OTEC plant if a single-glazed flat-plate solar collector of 5000-m² effective area is installed to boost the temperature of warm sea water by 20 K.     

Selective steam reforming of methanol over silica-supported copper catalyst prepared by sol–gel method

Silica-supported copper prepared by a sol–gel method can selectively catalyze methanol steam reforming to hydrogen and carbon dioxide at 250 °C. The catalytic activity increases with the copper content up to 40 wt.%. The selectivity to carbon monoxide with the catalysts containing 20–40 wt.% of copper is significantly lower than that with a commercial Cu/ZnO/Al₂O₃ catalyst. Copper particles are highly dispersed in the catalyst whose Cu content is 20 wt.% or less. After the reaction at 250 °C the particles are present as Cu₂O with the mean crystallite size less than 4 nm. In the catalyst with the Cu content of 30–50 wt.%, the fine Cu₂O particles coexist with large metallic Cu particles whose mean crystallite size is 30–40 nm after the reaction. The large metallic particles are supposed to contribute to the reaction as well as the fine Cu₂O particles although the surface area is estimated to be significantly smaller than that of the latter.     

Transmission electron microscopy study on the growth of zinc oxide crystals under hydrothermal conditions

ZnO crystals were grown in the presence of ZnO nanorod seeds under hydrothermal conditions while the same location on the ZnO nanorod was repeatedly observed by transmission electron microscopy. The surface of the ZnO seed crystal was covered with an amorphous layer during the early stages of crystallization (0.5-1.5 h). This amorphous layer was subsequently transformed into nanocrystals after 3.0 h. Finally, after 5.0 h, ZnO seeds suddenly grew preferentially in the [001] direction. These results suggest that the formation process of an amorphous ZnO layer on the surface of the seed crystals and its subsequent crystallization plays an important role in the induction of further crystal growth of ZnO nanorods.     

D-allose protects against endotoxemic acute renal injury

D-allose is a monosaccharide. We previously reported that D-allose attenuated renal injury by inhibiting the activation of neutrophils after renal ischemia/reperfusion. Lipopolysaccharide (LPS) triggers sepsis syndrome by activating monocytes to produce proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha, which potently stimulates the activation of neutrophils. This study was undertaken to examine the effects of D-allose on renal injury in the systemic inflammatory response induced by LPS administration, with emphasis on systemic TNF-alpha and the activation of neutrophils in the rat kidney. Serum and renal TNF-alpha, renal cytokine-induced neutrophil chemoattractant (CINC)-1, and myeloperoxidase (MPO) concentrations, and renal function after LPS administration were evaluated. D-allose (400 mg/kg body weight) inhibited LPS-induced increases in serum and renal TNF-alpha concentrations and renal CINC-1 and MPO concentrations after LPS administration, as well as the subsequent neutrophil-mediated renal injury. These findings may have important implications in understanding the biologic functions of D-allose. D-allose may prove useful in protecting against acute renal injury in systemic inflammatory responses to LPS.     

Programmable self-assembly of metal ions inside artificial DNA duplexes

The ultimate bottom-up approach for the construction of functional nanosystems requires the precise arrangement of atoms and molecules in three dimensions. DNA is currently one of the most prominent molecules able to self-assemble into complex networks and is therefore regarded as the 'silicon of the nano-world'. Metals and metal ions, in contrast, are the atomic building-blocks needed in such materials to establish functions such as electrical conductivity or magnetism. Here we report a new concept, which efficiently combines metal ions and DNA. The DNA structure is used as a matrix to program robustly the complexation of different metal ions under precise control with regard to element, number and composition.     

Low-temperature synthesis of ZnO nanorods using a seed layer of zinc acetate/sodium dodecyle sulfate nanocomposite

Aligned ZnO nanorods were synthesized by a simple hydrothermal method without calcination. A seed layer of zinc acetate (ZnAc₂)/sodium dodecyle sulfate (SDS) nanocomposite was used for nucleation of ZnO nanorods. First, a ZnAc₂/SDS composite was deposited on a Si substrate by spin-coating. And then, ZnO nanorods were grown under hydrothermal conditions at 90 °C. ZnO crystals were grown in the direction of c-axis perpendicular to the surface of the Si substrate. However, nucleation did not occur on the substrate of a ZnAc₂ seed layer without SDS, indicating that the presence of the ZnAc₂/SDS seed enhanced the nucleation of ZnO crystals. These results show that high dispersion of ZnAc₂ in the nanocomposite effectively assists a nucleation of ZnO crystals.