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Abstract: Objectives: Epidemiological and animal studies have shown that maternal obesity predisposes the offspring to obesity and the metabolic syndrome, possibly via late-onset metabolic programming of the fetus. Little is known, however, about the metabolic effect of maternal obesity on the fetus. This study investigated the effect of a maternal high-fat diet (HFD) on fetal growth and glucose metabolism using a diet-induced obesity mouse model. Study design: Female mice (6 weeks old; C57BL/6N) were fed either a normal chow diet (NCD, 10kcal% fat) or an HFD (60kcal% fat) for 4 weeks before mating and throughout pregnancy. At 17 days of gestation, gene expression of inflammatory markers and adipokines in fetal subcutaneous adipose tissue was analyzed by quantitative real-time polymerase chain reaction. Results: HFD mice were overweight, glucose intolerant and insulin resistant compared with NCD mice of the same gestational age. Although fetal body weight was not significantly different, fetal plasma glucose and insulin levels were higher in the HFD group than the NCD group. Furthermore, examination of fetal subcutaneous adipose tissue in the HFD group revealed hypertrophy with an increase in the levels of cluster of differentiation-68, chemokine receptor-2 and tumor necrosis factor-α mRNA, but a decrease in the level of glucose transporter-4 mRNA. Conclusion: Maternal HFD causes inflammatory changes in the adipose tissue of offspring. [Copyright &y& Elsevier]

Abstract: Highly active photocatalysts were synthesized by leaching of heat-treated titanium dioxide (TiO2)/hydroxyapatite (HAp) powder with hydrochloric acid at 0.25, 0.50, 0.75mol/l, and their photocatalytic activities were evaluated from in situ Fourier transform infrared (FT-IR) study of photo-oxidation of gaseous ethanol. By changing the acid concentration, the TiO2/HAp composite had different atomic ratios of Ca/Ti (0.0–2.8) and P/Ti (0.3–2.1). It was found that phosphate group remained on the surface of TiO2 particle even in the sample treated with concentrated acid (0.75mol/l). These acid-treated samples showed higher rates for ethanol photo-oxidation than the commercial TiO2 powder, Degussa P25. The highest rate was obtained in the TiO2/HAp composite treated with the dilute (0.25mol/l) acid in spite of its low content of TiO2 photocatalyst. This enhanced photocatalytic activity was attributed to the result that the deactivation with repeated injections of ethanol gas was suppressed in the TiO2/HAp composites compared with the TiO2 powders. [Copyright &y& Elsevier]

Abstract: The kinetics of photodegradation of methylene blue (MB) dye by titanium dioxide (TiO2) powder were investigated using elementary reactions. TiO2 powders were prepared by a selective leaching method consisted of processes of CaHPO4 precipitation, heat treatment, and acid leaching to obtain high crystalline anatase. The obtained TiO2 samples had wide ranges of specific surface areas (5–23m2/g) and densities of Ti3+ defects (90–480×1012spin/g) without a significant change in the anatase phase ratio ranging 0.86–0.91 in mass ratio. The MB photodegradation rate was expressed as functions of specific surface area and density of Ti3+ defects under the experimental condition that the photodegradation rate was proportional to UV irradiation intensity and the adsorbed MB amount was proportional to specific surface area. A proposed equation for calculation of photodegradation ate demonstrated greater effect of specific surface area than density of Ti3+ defects for MB photodegradation. [Copyright &y& Elsevier]

Abstract: A novel synthesis method of a highly active photocatalyst was proposed. Titanium dioxide (TiO2) nano-particles were prepared by three-step procedure, precipitation of hydroxyapatite (HAp) on TiO2 particles, heat treatment of the TiO2/HAp composites, and acid treatment in hydrochloric acid. The unique point of this procedure is the selective dissolution of HAp to obtain exposed TiO2 surfaces. The HAp precipitation was achieved by stirring TiO2 powders in the mixtures of Ca(NO3)2 and NH4H2PO4 aqueous solutions at pH 8.5. Then, the heat-treated TiO2/HAp composites were treated with hydrochloric acid. The precipitated HAp avoided the direct contact of TiO2 particles and suppressed the phase transformation from anatase-to-rutile >200°C. The HAp also suppressed a decrease of specific surface area of TiO2 during the heat treatment. The photocatalytic activities were evaluated from an absorbance decrease of methylene blue (MB) under ultraviolet (UV) irradiation. The MB photodecomposition was approximated to the first-order reaction and the reaction rate constants of the obtained TiO2 powders heated at various temperatures were higher than those of conventional TiO2 powders heated at same temperatures. The enhanced photocatalytic activity is attributed to the suppression effects for the phase transformation to rutile phase and the decreasing of specific surface area in the heat treatment. [Copyright &y& Elsevier]

We have prepared various (Ge[sub1-y] Pb[suby])[sub1-x]Mn[subx] Te thin films by an ionized cluster beam method on BaF[sub2] (111) substrates in order to study the dependences of electrical and magnetic properties on Pb content. Carrier concentration can be controlled from 10[sub18] cm[sup-3] (y = 0.69) to 10[sup21] cm[sup3] (y = 0) by Pb content in the films with Mn content x around 0.1. Direct magnetization and magneto- transport measurements were performed and the characteristics of anomalous Hall effect agreed well with the magnetization. The Curie temperature of (Ge[sub1-y] Pb[suby])[sub1-x] Mn[subx] Te films decreased with increasing Pb content and ferromagnetic behavior was not observed in magnetotransport measurement at 9K for the films above y = 0.57. An increase of Mn content in (Ge[sub1-x]Pb[suby])[sub1-x]Mn[subx] Te films with Pb content y around 0.47 has also been tried. The Curie temperature successfully increased with increasing Mn content till x = 0.22. [ABSTRACT FROM AUTHOR]

• Effects of operational parameters for selective In recovery were studied in CCFS. • The optimized conditions of the selective recovery were described. • Dose of ascorbic acid into metal solution improves the In/Fe separation. • Excess concentration of anionic organophosphate deteriorates the separation performance. Continuous counter-current foam separation under the simultaneous injections of metal and surfactant solutions into rising foam bed was applied to recover In(III) from a sulfuric acid solution. In this system, an anionic organophosphate surfactant containing a similar structure to a phosphoric acid extractant, D2EHPA, was employed as the metal collector with addition of a nonionic co-surfactant as a foam stabilizer. Among the various commercial products available, A219B/POOE20 was elucidated as the optimum combination of anionic/nonionic surfactants. In this study, the effects of the experimental parameters such as the aqueous pH, air flow rate, and injection rates of metal and surfactant solutions were discussed in terms of the percent recovery and separation factors of In(III) over the other metals. The results were successfully obtained under the optimized conditions with a dose of ascorbic acid as a reductant for Fe(III); the percent recoveries of indium and iron; the separation factors of In/Fe, In/Cu, and In/Zn; and the enrichment ratio of indium were 97%, 1.1%, 93, 1300, 1300, and 5.5, respectively. The mixture mol ratio of mono- and di-esters of anionic A219B was derived as 35:65 by a slope analysis, and the mono-esters would influence the separation performance in the case of rich A219B concentration in foam bed. The performance comparison of this method with solvent extraction using D2EHPA or the conventional foam separation was also presented. [ABSTRACT FROM AUTHOR]