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31.
Plant Foods for Human Nutrition - The two main components from a Nelumbo nucifera leaf extract (NnEx) were investigated for their ability to prevent triglyceride accumulation and promoting...  相似文献   
32.
Desorption experiments were conducted on 21 soils at 3 atrazine concentrations. The Freundlich isotherm was used to estimate atrazine desorption. For the relationship between Freundlich isotherm coefficients, log K F and 1 / n, 1 / n was also represented by a linear regression of log K F as in the case of atrazine adsorption. All the linear regression lines of desorption exhibited larger slopes and intercepts than those of adsorption. When the atrazine concentration was high, the slope and intercept values were smaller than those for the desorption regression lines. The results showed that the larger the capacity of a soil to adsorb atrazine, the lesser the amount of atrazine desorbed. For the cultivated soils except for Andisols, the percentages of atrazine taken from solutions using the sequential exchange method after the first adsorption experiments, were the same as those desorbed from soils in relation to the initial amount adsorbed. Thus, reversible adsorption occurred in the soils due to weak physical adsorption.  相似文献   
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The mechanical properties of 613 small clear specimens of 35 species (11 ring-porous hardwoods, 19 diffuse-porous hardwoods, and 5 softwoods) were evaluated. The aim of the study was to examine indexes of wood quality that are easy to measure and that exhibit a high correlation with bending performance and hardness that are essential properties of hardwood products. The modulus of rigidity, dynamic modulus of elasticity, bending properties (modulus of elasticity, modulus of rupture, stress at the proportional limit, absorbed energy, Tetmajer’s modulus), dynamic energy absorption by an impact bending test, compressive strength parallel to the grain, shear strength, partial bearing strength, and Brinell’s hardness were measured. A high correlation was found between dynamic modulus of elasticity and static modulus of elasticity. Bending stress at the proportional limit was found to be approximately equivalent to the compressive strength parallel to the grain. Static energy absorption correlated with dynamic energy absorption. Tetmajer’s modulus was found to be closely related to the ratio of the initial stiffness within the elastic range to the secant modulus at the maximum load. A high correlation was observed between Brinell’s hardness and partial bearing strength. The difference in the regression coefficients obtained for these correlations between the species groups was small. Part of this study was presented at the All Division 5 Conference of IUFRO, Taipei, October 2007  相似文献   
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Three rearranged phragmalin-type limonoids, khayanolide A, khayanolide B and 1-O-acetylkhayanolide B, and a mexicanolide-type limonoid, khayalactol, have been isolated from the stem bark of Khaya senegalensis (Desr) A Juss (Meliaceae). The antifeedant and growth-inhibitory activities of the isolated compounds were evaluated on Spodoptera littoralis (Boisduval). When added to an artificial diet, khayanolide A, khayanolide B and 1-O-acetylkhayanolide B showed antifeedant activity in a concentration-dependent manner. Khayalactol exhibited strong antifeedant activity without significant differences at all of the tested concentrations (7.5-100 mg kg(-1)). Khayanolide B was the most potent antifeedant with an ECso of 2.19 mg kg(-1). The results also revealed that the isolated compounds caused marked larval growth inhibition on S littoralis after 7 days of feeding on treated diet; this effect was concentration-dependent. Khayanolide B was the most active growth inhibitor among the isolated compounds, with an EC50 of 6.96 mg kg(-1).  相似文献   
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Oocyte-specific linker histone H1foo is localized in the oocyte nucleus, either diffusely or bound to chromatin, during the processes of meiotic maturation and fertilization. This expression pattern suggests that H1foo plays a key role in the control of gene expression and chromatin modification during oogenesis and early embryogenesis. To reveal the function of H1foo, we microinjected antisense morpholino oligonucleotides (MO) against H1foo into mouse germinal-vesicle stage oocytes. The rate of in vitro maturation of the antisense MO group was significantly lower than that of the control group. Eggs that failed to extrude a first polar body following injection of antisense MO arrested at metaphase I. Additionally, co-injection of in vitro synthesized H1foo mRNA along with antisense MO successfully rescued expression of H1foo and improved the in vitro maturation rate. There was no difference in the rate of parthenogenesis between the antisense MO and control groups. These results indicate that H1foo is essential for maturation of germinal vesicle-stage oocytes.  相似文献   
38.
This work aimed to measure the cross-sectional moisture distribution in a cylindrical body using a double-glass-tube model filled with water and to construct an electric network model that explains the effects of moisture distribution. A new impedance measurement system introducing an intermediate electrode was exploited. The electrode was used to segregate the target local current from the whole current in a cross section of a specimen. Three model cylinders with different moisture distributions were used, and absolute values of impedance and phase were measured over the frequency range 1 kHz to 1 MHz. By introducing an intermediate electrode, frequency responses of the impedance and the phase showed characteristic changes in the high-frequency range associated with the moisture distributions. The trends were simulated numerically by using electric network analysis. The proposed method enabled measurement of a selective current path in the cross section of a cylindrical body.  相似文献   
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After the tsunami caused by the Great East Japan Earthquake, marine sediment was taken from the sea bottom and deposited over local agricultural fields. The marine sediment already contained an unknown amount of heavy metals, due to anthropogenic activities prior to the tsunami, which might affect plants, animals, and humans. Furthermore, soil salinity in tsunami-inundated land greatly increased. Three different amounts of steel slag were employed as pretreatment agent in order to improve agricultural soil quality. The soil samples treated with 2% of steel slag present a remarkable increase of A. thaliana biomass production with low BCF and TF values for most of the heavy metals. It was concluded that steel slag pretreatment used in the tsunami-inundated agricultural lands produced a noteworthy improvement in soil quality which lead to a positive stimulative effect on plant growth, and the slag addition treatment proved to be a promising treatment that might be used for phytostabilization of slightly contaminated soils.  相似文献   
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