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This article examines the international crude oil trade and the international petroleum trade through econometric analysis and complex network analysis, focusing on the aspects of the driving forces and resistances for the oil trade and competitive or cooperative relationships among countries. The crude oil trade network and the petroleum trade network are constructed. Positional and role analysis reveals that countries can be divided into five positions in the crude oil trade network and twenty-five positions in the petroleum trade network. The relationships among countries within or between positions are discussed and recognized as competitive or cooperative. The bilateral oil trade analysis shows that various factors within countries have influence on bilateral trade volume. The analysis also implies that restrictions on trade partner selection due to geographical resistance forces neighboring oil-importing countries to choose similar oil-exporting countries, which corresponds with the results of the complex network analysis. The complex network analysis shows that the countries in the same position belong to the same region. Furthermore, the analysis results imply that the diversification in petroleum-exporting countries reduces the supply disruption risk for importing countries.

The effects of several electrolyzed waters were evaluated on the permeation of model base, acid and non-ionized compounds, lidocaine (LC), benzoic acid (BA), and isosorbide mononitrate (ISMN), respectively, through excised hairless rat skin. Strong alkaline-electrolyzed reducing water (ERW) enhanced and suppressed the skin permeation of LC and BA, respectively, and it also increased the skin permeation of ISMN, a non-ionized compound. On the contrary, strong acidic electrolyzed oxidizing water (EOW) enhanced BA permeation, whereas suppressing LC permeation. Only a marginal effect was observed on the skin permeation of ISMN by EOW. These marked enhancing effects of ERW on the skin permeation of LC and ISMN were explained by pH partition hypothesis as well as a decrease in skin impedance. The present results strongly support that electrolyzed waters, ERW and EOW, can be used as a new vehicle in topical pharmaceuticals or cosmetics to modify the skin permeation of drugs without severe skin damage.

Bactericidal activities of several electrolyzed waters were evaluated by time-kill assay using Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Strongly acidic electrolyzed oxidizing water (EOW) showed remarkably high bactericidal activity against all four bacterial strains, including a spore-forming bacterium, B. subtilis. Strongly alkaline electrolyzed reducing water (ERW) exhibited high bactericidal activity against gram-negative bacteria (E. coli and P. aeruginosa), whereas it showed low or no bactericidal activity against gram-positive bacteria. In contrast, hydrogen water (HW) showed only low bactericidal activity against two (S. aureus and P. aeruginosa) of the four strains tested, and weak acidic electrolyzed reducing water (WA-ERW) did not show any bactericidal activity. Thus, it was demonstrated that among several electrolyzed waters, EOW possessed high bactericidal activity against all four bacterial strains regardless of gram-negative or gram-positive status and against their spore formation. It was also suggested that some electrolyzed waters might be applicable as disinfectants or antiseptic agents instead of normal purified water in pharmaceutical preparations or cosmetics.

This study was conducted to evaluate the pretreatment effects of different in vivo moxibustion on the permeation of a model high molecular compound, FITC-dextran, with a mean molecular weight of 4 kDa (FD-4), through excised hairless rat skin. Direct or indirect moxibustion (0.10 g moxa) was pretreated consecutively 4 times every 5 min on the abdomen of hairless rats, and the permeation of FD-4 was determined through the excised skin over 8h from 30 min after starting the first moxibustion. This consecutive moxibustion pretreatment showed a significant increase in the skin temperature as well as skin permeation of FD-4 compared with the control group (no moxibustion pretreatment). Quantitative parameters showed an increase in skin temperature and skin permeation: the area under the skin temperature over control temperature-time curve during one burning cycle (5.0 min) (AUCtemp) or the maximum skin temperature during moxibustion (Tmax) and the cumulative amount of FD-4 permeated through skin over 8h (Q8) or steady-state flux were increased by moxibustion pretreatment. Then, the effect of pedestal thickness (distance from the moxa cylinder and skin surface), shape of the moxa cylinder (5mm diameter, 13 mm height or 9 mm diameter, 7 mm height), burning materials (moxa or aromatic incense), pedestal component (paper, potato or ginger) and moxibustion pretreatment method (direct or indirect moxibustion) was evaluated on the AUCtemp or Tmax and Q8 or flux. The amount of protein leached from the skin surface was also determined as an inflammatory index by this moxibustion pretreatment. When the skin temperature was increased to 60 degrees C, the Q8 or flux as well as the amount of protein leached were markedly increased. When the skin temperature was controlled to 42 to 45 degrees C by an adequate selection of pedestal thickness, shape of the moxa cylinder, burning materials, pedestal component and moxibustion pretreatment method, on the other hand, protein leaching remained unaltered, but the Q8 or flux significantly increased with the Tmax. This study thus provides credible evidence that moxibustion pretreatment increases the skin permeation of high molecular compounds.