The Inhibition Effect of Photo-Cross-Linking between Probes in Photo-Induced Double Duplex Invasion DNA

Double duplex invasion (DDI) DNA is a useful antigene method that inhibits expression of genomic DNA. We succeeded in performing photoinduced-DDI (pDDI) using ultrafast photo-cross-linking. 5-Cyanouracil (^CNU) has been used in pDDI to inhibit photo-cross-linking between probes, but its importance has not been clarified. Therefore, in this study, we evaluated the effect of spacer (S) and d-spacer (dS) that exhibit photo-cross-linking ability similar to that of ^CNU. ^CNU exhibited the highest pDDI efficiency, and S, dS, and T were not very different. The photo-cross-linking inhibitory effect was better with S and dS than with thymidine (T). Conversely, the thermal stability was significantly lower with S and dS than with T. The results suggest that the pDDI efficiency is determined by the balance between the photo-cross-linking inhibitory effect and the thermal stability, which is the introduction efficiency for double-stranded DNA. Therefore, ^CNU, which has a photo-cross-linking inhibitory effect and a high T_m value, showed the highest inhibitory efficiency.     

Relationship between IgA Nephropathy and Porphyromonas gingivalis; Red Complex of Periodontopathic Bacterial Species

IgA nephropathy (IgAN) has been considered to have a relationship with infection in the tonsil, because IgAN patients often manifest macro hematuria just after tonsillitis. In terms of oral-area infection, the red complex of periodontal bacteria (Porphyromonas gingivalis (P. gingivalis), Treponema denticol (T. denticola) and Tannerella forsythia (T. forsythia)) is important, but the relationship between these bacteria and IgAN remains unknown. In this study, the prevalence of the red complex of periodontal bacteria in tonsil was compared between IgAN and tonsillitis patients. The pathogenicity of IgAN induced by P. gingivalis was confirmed by the mice model treated with this bacterium. The prevalence of P. gingivalis and T. forsythia in IgAN patients was significantly higher than that in tonsillitis patients (p < 0.001 and p < 0.05, respectively). A total of 92% of tonsillitis patients were free from red complex bacteria, while only 48% of IgAN patients had any of these bacteria. Nasal administration of P. gingivalis in mice caused mesangial proliferation (p < 0.05 at days 28a nd 42; p < 0.01 at days 14 and 56) and IgA deposition (p < 0.001 at day 42 and 56 after administration). Scanning-electron-microscopic observation revealed that a high-density Electron-Dense Deposit was widely distributed in the mesangial region in the mice kidneys treated with P. gingivalis. These findings suggest that P. gingivalis is involved in the pathogenesis of IgAN.     

Calcium Silicate Carbonation Products

calcium silicates such as C₃S, βT-C₂S, and γgM-C₂S ^† were carbonated under saturated humidity at room temperature. Carbonation products were examined by DT-TGA, gasphase mass spectroscopy, and XRD. Two types of carbonate were produced: one type, which was rather poorly crystallized, was decarbonated at a very low temperature, below 600°C; the other type was a crystalline phase such as calcite, aragonite, and/or vaterite which was decarbonated above 600°C. The data were compared to existing data for calcium carbonates and basic calcium carbonates. The results suggest that an amorphous calcium silicate hydrocarbonate was one of the carbonation products which formed during the hydration/carbonation reaction.     

The effect of the volume fraction of dispersed phase on toughness of injection molded polypropylene blended with SEBS,SEPS, and SEP

The effect of the volume fraction of a dispersed phase on improvement in the toughness of injection‐molded isotactic polypropylene (i‐PP), blended with a styrenic thermoplastic elastomer, has been studied. The volume fraction of the dispersed phase, which indicates compatibility between elastomer and i‐PP, depends on the molecular structure of a soft segment and the copolymerization ratio of styrene. The volume fraction of the dispersed phase of the i‐PP blended with styrene‐ethylene‐propylene‐styrene tri‐block copolymer (SEPS) was higher than that of the i‐PP blended with styrene‐ethylene‐butylene‐styrene tri‐block copolymer (SEBS). The volume fraction of the dispersed phase increases as the copolymerization ratio of styrene increases. Improvement in the toughness of the blended i‐PP clearly depends on relaxation of strain constraint by void formation from the dispersed phase. Its efficiency proved to be dependent on the strength and the volume fraction of the dispersed phase depending on the compatibility between elastomer and i‐PP. POLYM. ENG. SCI., 45:1630–1638, 2005. © 2005 Society of Plastics Engineers     

Layer-by-layer growth of graphene layers on graphene substrates by chemical vapor deposition

We demonstrate a synthesis of graphene layers on graphene templates prepared by the mechanical exfoliation of graphite crystals using a developed chemical vapor deposition (CVD) apparatus that has a furnace with three temperature zones and can regulate the temperatures separately in each zone. This results in individual control over the decomposition reaction of the carbon feedstock and the growth of graphene layers by activated carbon species. CVD growth using multi-temperature zones provides wider temperature windows appropriate to grow graphene layers. We observed that graphene layers proceed by a layer-by-layer growth mode using an optical microscopy, an atomic force microscopy, and Raman spectroscopy. This result suggests that a graphene growth technique using the CVD apparatus is a potential approach for making graphene sheets with precise control of the layer numbers.     

Selective oxidation of methanol in exhaust gas containing aromatic compounds

The activity of exhaust catalysts of methanol and gasoline mixture fueled automobiles is inhibited by coexistent aromatic compounds contained in the exhaust stream. One approach to avoid this inhibition could be the utilization of a molecular-sieve effect. It seems probable that the migration of aromatic compounds, which have larger molecular sizes than that of methanol, will be blocked by these supports and methanol will selectively reach the active sites of the catalysts. Thus, we examined the simultaneous oxidation of methanol and toluene over some ion-exchanged Pt/zeolite catalysts. Experimental results showed that ion-exchanged Pt/zeolite catalysts are less affected by coexistent toluene and have a higher selectivity for methanol oxidation compared with an alumina-supported platinum catalyst, suggesting that the use of these catalysts is effective for oxidizing methanol in the exhaust stream containing aromatic compounds. Among the catalysts tested, a Pt/H-MOR catalyst was found to be the most effective for the oxidation of methanol and effectively catalyzed the reaction in the presence of toluene even at low temperature.     

Fluid flow and heat transfer of natural convection over upward‐facing,horizontal, heated plate shrouded by a parallel insulated plate

The present paper describes experimental results on the fluid flow and heat transfer of natural convection between a horizontal, heated plate facing upward and an insulated cover plate. The experiments were carried out with water. The width of the test plates W and their gaps H were changed from W = 50 to 250 mm and H = 10 to 30 mm and ∞ (no cover plate). The visualization studies with dye and liquid crystal thermometry revealed that the roll cells whose axes are perpendicular to the flow direction appear and become dominant over the heated plate on decreasing the gap. These roll cells inhibit the heat transfer, and thus, the heat transfer coefficients become smaller than those without a cover plate. It was found that the flow and heat transfer in the region near the plate edges are unaffected by the cover plate. The conditions of the above reduced heat transfer were determined empirically. Moreover, nondimensional correlations for the local and the overall heat transfer coefficients of the heated plates are proposed based on the present heat transfer results. © 2000 Scripta Technica, Heat Trans Asian Res, 29(4): 333–346, 2000     

Application of eddy current inversion technique to the sizing of defects in Inconel welds with rough surfaces

This paper evaluates the applicability of eddy current inversion techniques to the sizing of defects in Inconel welds with rough surfaces. For this purpose, a plate Inconel weld specimen, which models the welding of a stub tube in a boiling water nuclear reactor is fabricated, and artificial notches machined into the specimen. Eddy current inspections using six different eddy current probes are conducted and efficiencies were evaluated for the six probes for weld inspection. It is revealed that if suitable probes are applied, an Inconel weld does not cause large noise levels during eddy current inspections even though the surface of the weld is rough. Finally, reconstruction of the notches is performed using eddy current signals measured using the uniform eddy current probe that showed the best results among the six probes in this study. A simplified configuration is proposed in order to consider the complicated configuration of the welded specimen in numerical simulations. While reconstructed profiles of the notches are slightly larger than the true profiles, quite good agreements are obtained in spite of the simple approximation of the configuration, which reveals that eddy current testing would be an efficient non-destructive testing method for the sizing of defects in Inconel welds.