Photocatalytic oxidation of CO with various oxidants by Mo oxide species highly dispersed on SiO2 at 293 K

The photocatalytic oxidation of CO into CO₂ with oxidants such as NO, N₂O and O₂ proceeded efficiently on a Mo/SiO₂ with high Mo dispersion under UV light irradiation. It was found that the reaction rate greatly depended on the kind and concentration of the oxidant. Photoluminescence investigations reveal the close relationship between the reaction rate and the relative concentration of the photo-excited Mo⁶⁺-oxide species, i.e. charge transfer–excited–triplet state (Mo⁵⁺–O⁻)^*, under steady-state reaction conditions. Moreover, the photocatalytic oxidation of CO with O₂ in excess H₂ was carried out to test suitability for applications to supplying pure H₂. This reaction was seen to proceed efficiently on Mo/SiO₂ with a high CO conversion of 100% and CO selectivity of 99% after 180 min under UV light irradiation, showing higher photocatalytic performance than TiO₂ (P-25) photocatalyst. UV–vis, XAFS, photoluminescence and FT-IR investigations revealed that the high reactivity of the charge transfer–excited–triplet state (Mo⁵⁺–O⁻)^*, with CO as well as the high reactivity of the photoreduced Mo-oxide species (Mo⁴⁺-species) with O₂ to produce the original Mo-oxide species (Mo⁶⁺O²⁻), played a crucial role in the reactions.     

Effects of surfactants and inorganic phosphates upon apparent viscosities of pigment-water (50–50) suspensions

The effects of various types of surfactants and inorganic phosphates upon the apparent viscosities of pigment-water (50/50) suspensions are examined. The additions of surfactants or inorganic phosphates to the pigment-water suspensions depress the apparent viscosities from the values of more than 10,000 centipoise to those of ca. 10 centipoise. The concentration of surfactants or inorganic phosphates required to depress the apparent viscosity depends upon the chemical composition and the mol wt of surfactants or inorganic phosphates. The effects are correlated with zeta potential, adsorption, and pH data.     

Direct observation of the interaction between vortices and dislocations in superconducting crystals by a cryo-Lorentz EM (interaction between vortices and dislocations)

Quantized magnetic flux lines (vortices) in a Nb foil were directly observed in different magnetic fields up to 200 G by a cryo-Lorentz electron microscope. The interaction of vortices with dislocations in the specimen was examined and clarified; edge-on dislocations weakly pin individual vortices at magnetic fields below 100 G. In higher magnetic fields the formation of a regular hexagonal vortex lattice started preferentially at in-plane dislocations. At 200 G the Abrikosov vortex lattice was formed with small domains, whose centre included the dislocations, showing their important role on the formation of the vortex lattice. For a NbTi foil no clear image of vortices could be seen, because the surface was rough due to the formation of fine grains and precipitates.     

Performance of plastic gear made of carbon fiber reinforced poly-ether-ether-ketone

A carbon fiber (CF) reinforced poly-ether-ether-ketone (PEEK) gear was prepared by injection molding, and its gear performance was evaluated. It was found that the wear process of the CF reinforced PEEK gear significantly varied depending on the test conditions, such as the kind of the partner gear combined and whether a lubricant exists on the engagement region or not. It was assumed that the existence of transfer film at the engagement region, the affinity between PEEK and CF, the compression modulus as well as surface hardness of the partner gear, and the characteristics of CF play a role of differentiation in the wear depth.     

Preparation and mechanical properties of polystyrene–clay hybrids

Polystyrene–clay hybrids (PSCHs) were prepared by melt blending a styrene vinyloxazoline copolymer with organophilic clay. In the PSCHs, the silicate layers of the clay were delaminated and dispersed homogeneously to the nanometer level. The moduli of the PSCHs were higher than that of the PS copolymer. For example, the tensile modulus of the PSCH with 5 wt % clay was 1.4 times higher compared to that of the PS copolymer. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3359–3364, 1999     

Oral Squamous Cell Carcinoma Contributes to Differentiation of Monocyte-Derived Tumor-Associated Macrophages via PAI-1 and IL-8 Production

Tumor-associated macrophages (TAMs) promote cancer cell proliferation and metastasis, as well as anti-tumor immune suppression. Recent studies have shown that tumors enhance the recruitment and differentiation of TAMs, but the detailed mechanisms have not been clarified. We thus examined the influence of cancer cells on the differentiation of monocytes to TAM subsets, including CD163⁺, CD204⁺, and CD206⁺ cells, in oral squamous cell carcinoma (OSCC) using immunohistochemistry, flow cytometry, and a cytokine array. Furthermore, we investigated the effect of OSCC cells (HSC-2, SQUU-A, and SQUU-B cells) on the differentiation of purified CD14⁺ cells to TAM subsets. The localization patterns of CD163⁺, CD204⁺, and CD206⁺ in OSCC sections were quite different. The expression of CD206 on CD14⁺ cells was significantly increased after the co-culture with OSCC cell lines, while the expressions of CD163 and CD204 on CD14⁺ cells showed no change. High concentrations of plasminogen activator inhibitor-1 (PAI-1) and interleukin-8 (IL-8) were detected in the conditioned medium of OSCC cell lines. PAI-1 and IL-8 stimulated CD14⁺ cells to express CD206. Moreover, there were positive correlations among the numbers of CD206⁺, PAI-1⁺, and IL-8⁺ cells in OSCC sections. These results suggest that PAI-1 and IL-8 produced by OSCC contribute to the differentiation of monocytes to CD206⁺ TAMs.     

No. 3Vol. 42, No. 2, pp. 94–101, 2008Effect of Birch (Betula platyphylla Sukatchev var. japonica Hara) sap on cultured human epidermal keratinocyte differentiation

The beauty of ideal skin texture is closely associated with dermal moisture factors. The key factors of skin moisture are NMF (natural moisturizing factor) and skin normal barrier function. The former keeps dermal surface moisture, and the later protects from excess water loss. So we have searched for the ingredient that improves these factors. Birch sap has been widely used as an effective drink for anti-fatigue and anti-stress. However, the effect of birch sap on skin as a cosmetic agent has not been known entirely. In this study, we investigated the effects of birch ( Betula platyphylla Sukatchev var. japonica Hara) sap on human skin. Birch sap induced epidermal keratinocyte differentiation properties in vitro . We assessed two epidermal differentiation agents. Filaggrin is a precursor protein of NMF, and involucrin is one of the precursor proteins of the cornified cell envelope (CE), which is related to normal barrier function. We have evaluated the production of these proteins where birch sap was applied to human normal keratinocytes. Birch sap not only increased mRNA expression of filaggrin and involucrin, but also accelerated these proteins production. Otherwise, birch sap did not have any influence for IL-6 production, which is related to inflammatory and aberrant keratinocyte proliferation. The results of induced differentiation properties on birch sap-treated keratinocytes are very similar to the differentiation induced by calcium in vitro . This similarity suggested that birch sap has a differentiation inducible property on in vitro cultured keratinocytes. Our study suggested that birch sap is able to control both moisturizing- and barrier-related factor production. From these effects, birch sap provides appropriate epidermal functions and skin homeostasis, and revealed itself as a very useful ingredient in the cosmetic field.     

An unsteady flow structure on a heated rotating disk under mixed convection

A flow field under mixed convection on a heated rotating disk has been measured using an ultrasonic velocity profiler (UVP). The measured velocity field is a spatio‐temporal one as a function of radial coordinates and time. The objective of this paper is to clarify the vortex structure caused by the instability between buoyancy and centrifugal force. The vortex appears under typical conditions of Reynolds numbers and Grashof numbers and it moves toward the outside of the disk. This behavior can be classified into two patterns. The size of the vortex structure decreases with an increasing Reynolds number and increases with the Grashof number. The traveling velocity of the vortex increases with the Grashof number. Moreover, it decreases with an increasing Reynolds number in spite of increasing centrifugal force. According to these results, the region dominated by natural, forced, and mixed convection is classified in the relationship between Reynolds and Grashof numbers. © 2005 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(6): 407–418, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20074     

Estimation and characterisation of major royal jelly proteins obtained from the honeybee Apis merifera

Royal jelly (RJ) contains many components, including proteins. We focused on major royal jelly proteins (MRJPs) under natural conditions, and attempted to determine the content ratios and molecular forms of MRJPs by size-exclusion HPLC, SDS–PAGE, 2-DE and MALDI TOF/TOF MS. Soluble RJ proteins were extracted by dialysis followed by several centrifugation techniques. Soluble RJ proteins were universally separated into five peaks (640 kDa, 280 kDa, 100 kDa, 72 kDa and 4.5 kDa) by size-exclusion HPLC on a Superose 12 column. Among these peaks, both the 280 kDa and 72 kDa peaks were major, but the intensity of the 280 kDa peak differed markedly among original RJ samples (n = 70). The main 280 kDa protein was separated into a 55 kDa band by reducing and non-reducing SDS–PAGE. This protein was also separated into multiple spots ranging from pH 4.2 to 6.5 by 2-DE. These spots were identified as MRJP 1 by MALDI TOF/TOF MS. From these results, MRJP 1 was thought to comprise an oligomer complex linked by non-covalent bonds under natural conditions. Another major protein, the 72 kDa peak on Superose 12 HPLC, was identified as MRJP 2.