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21.
Summary Hereditary changes of certain Mendelian traits in red pepper after grafting are described. It is suggested that these changes are induced by a mechanism similar to that of transformation in higher organisms.The abstracts of this paper and the parts to follow have been presented at the XIII International Congress of Genetics held in August 1973 at Berkeley, California, USA as both a contributed paper and an exhibit including real herbarial specimen and color pictures of the variants genetically analyzed.  相似文献   
22.
Turbulent diffusion from a fixed point-source is classified according to the length of the observation time with the aid of modern diffusion theory. The diffusion zone in the downwind is shown to consist of the linear, cuspidal, and parabolic zones. The effect of the observation time on the diffusivity coefficients and plume spreading is also discussed.  相似文献   
23.
ABSTRACT

Following the Fukushima Daiichi Nuclear Power Plant accident of 2011, the potential for radiocesium transfer from contaminated soils, such as Andosols, to agricultural crops became a significant concern. Andosols account for up to 70% of paddy soils in the northern and northwest areas of Tochigi Prefecture, where the radiocesium concentration is 1000 Bq kg?1 or greater in the soil of some fields. The present study was carried out in order to determine the phytoavailability of radiocesium in Andosols by comparing it with that of gray lowland soils in the first 3 years following the accident. The transfer factor (TF) tended to be higher in Andosols than in gray lowland soils, leading to higher radiocesium concentrations in brown rice grown in Andosols. The exchangeable potassium (Ex-K2O) in Andosols was highly and negatively correlated with TF, followed by clay. The Ex-K2O value was positively correlated with the clay/total carbon (T-C) value, suggesting that a high T–C ratio could weaken K2O adsorption on clay mineral sites; hence, the low clay/T-C values can partially explain the relatively large TF values of Andosols. Samples with Ex-K2O contents less than 200 mg kg?1 and with low clay/T-C values showed striking decreases in TF values from 2011 to 2012. However, the decrease from 2012 to 2013 was quite small; radiocesium in these samples was potentially available for rice uptake for a long time, likely due to the reversible adsorption and fixation characteristics of allophane. Most gray lowland soil samples showed very low TF values over the 3 years of the study, except for those with TF values greater than 0.1 due to low Ex-K2O and clay contents; the geometric mean (GM) value of TF was below 0.01 in 2012. The extraction of exchangeable radiocesium (Ex-Cs) with a 1 mol L?1 ammonium acetate solution may not be an appropriate method for explaining the variability in radiocesium TF in Andosols. This is because the Ex-Cs value was significantly correlated with Ex-K2O in Andosols, but not in gray lowland soils, indicating that Ex-K2O explained this variability in relation to Ex-Cs.  相似文献   
24.
Charge state distribution (CSD) and hydrogen/deuterium (H/D) exchange of preparations of alpha-lactalbumin (alpha-Lac) and beta-lactoglobulin (beta-Lg) were investigated using electrospray ionization mass spectrometry (ESI-MS). Storage of alpha-Lac at pH 3 resulted in substantial changes in its CSD, with the emergence of new ion species and shifts toward higher charge state, indicating less stable conformation. ESI spectra of alpha-Lac kept at pH 5.5 for 4 days showed stable conformation; however, extending the storage period resulted in substantial changes in CSD and a decrease in the stability of holo-alpha-Lac (Ca(2+)-bound form). In comparison to apo-alpha-Lac, the relative intensity of holo-alpha-Lac was higher at pH 6.8 but lower at pH 8 during the storage period. beta-Lg showed stable CSD at pH 3, substantial changes at pH 5.5, and minor changes at pH 6.8 and 8 during storage. The H/D exchange results demonstrate that the conformation of holo-alpha-Lac was more stable than that of apo-alpha-Lac and that the conformation of beta-Lg variant B was more stable than that of the beta-Lg variant A. Kinetics of H/D exchange indicated that alpha-Lac and beta-Lg fractions obtained from whey protein preparations have the same or improved conformational stabilities compared to those of alpha-Lac and beta-Lg standards. The presence of four or more hexose residues in alpha-Lac enhanced its conformational stability; the presence of two hexose residues in beta-Lg resulted in a less stable conformation.  相似文献   
25.
The performance of a commercially available microtiter plate ELISA kit for the determination of the neonicotinoid insecticide imidacloprid was evaluated for sensitivity, selectivity, influence of organic solvent used for extraction procedure, matrix interference originated from agricultural sample, accuracy, and method comparison with conventional HPLC analysis. The limit of detection for the kit (0.1 or 0.5 ng/mL) was determined. The working range (1-39 ng/mL) experimentally calculated on the basis of a criterion, which is determined as the range from I(20) to I(80), was comparable to that established by the manufacturer (1-50 ng/mL). The linearity of the standard curve based on the kit-assembled standard solutions agreed with the one based on the self-made standard solutions. Specificity studies indicate that the imidacloprid monoclonal antibody can readily distinguish the target compound from other structurally related neonicotinoid analogues and some metabolites, with the exception of clothianidin, the cross-reactivity of which was approximately 12%. To extract imidacloprid from an agricultural sample (apple) as simply and rapidly as possible, some extraction methods were examined. Consequently, the extraction method with hand-shaking for 5 min was the best among the examined methods. For the analysis of imidacloprid in apple samples, it was extracted directly with methanol and the extracts were diluted 10-fold (100-fold in the well) with water prior to ELISA analysis. No significant matrix interference was observed with the dilution factor. Recoveries of imidacloprid from fortified apple samples ranged from 87.7 to 112.0%. The results obtained with the ELISA kit correlated well with those by the reference method (conventional HPLC analysis) for apple samples (r > 0.998). These findings strongly indicate that the ELISA kit may be employed routinely for an on-site imidacloprid residue analysis of apple samples.  相似文献   
26.
27.
We previously determined that five rather hydrophobic metabolites appeared in blood plasma after oral administration of cyanidin 3-O-beta-D-glucopyranoside, but a group of hydrophilic metabolites still remained unidentified. In the present study, 12 hydrophilic metabolites found were collected from urine and plasma samples by high-performance liquid chromatography (HPLC) and then analyzed by tandem MS spectrometry. From the MS spectra, four metabolites out of 12 were assigned as glucuronides of cyanidin 3-O-beta-D-glucopyranoside and six out of 12 were glucuronides of the primary metabolites of cyanidin 3-O-beta-D-glucopyranoside (O-methyl cyanidin 3-O-beta-D-glucopyranoside). Extended glucuronides of cyanidin 3-O-beta-D-glucopyranoside and O-methyl cyanidin 3-O-beta-D-glucopyranoside showed their maximum plasma concentrations at 15 and 60 min (or 30 min) after oral administration, respectively. Their maximum plasma concentrations ranged from 15 to 70 nM. From the profile of urinary-excreted anthocyanins after intravenous administration, it was deduced that extended glucuronides of cyanidin 3-O-beta-D-glucopyranoside and O-methyl cyanidin 3-O-beta-D-glucopyranoside were mainly produced in the liver rather than by intestinal flora. The area under the plasma concentration curve was 0.25 micromol min/L for extended glucuronides of cyanidin 3-O-beta-D-glucopyranoside and 0.14 micromol min/L for O-methyl cyanidin 3-O-beta-D-glucopyranoside, respectively, when evaluated as cyanidin 3-O-beta-D-glucopyranoside equivalent, indicating that extended glucuronidation is a critical pathway in cyanidin 3-O-beta-D-glucopyranoside metabolism in rats.  相似文献   
28.
Percentile growth curves are often used as a clinical indicator to evaluate variations of children’s growth status. In this study, we propose empirical percentile growth curves using Z-scores adapted for Japanese Thoroughbred horses, with considerations of the seasonal compensatory growth that is a typical characteristic of seasonal breeding animals. We previously developed new growth curve equations for Japanese Thoroughbreds adjusting for compensatory growth. Individual horses and residual effects were included as random effects in the growth curve equation model and their variance components were estimated. Based on the Z-scores of the estimated variance components, empirical percentile growth curves were constructed. A total of 5,594 and 5,680 body weight and age measurements of male and female Thoroughbreds, respectively, and 3,770 withers height and age measurements were used in the analyses. The developed empirical percentile growth curves using Z-scores are computationally feasible and useful for monitoring individual growth parameters of body weight and withers height of young Thoroughbred horses, especially during compensatory growth periods.  相似文献   
29.
The variations in the light-dependent herbicidal activity against Echinochloa oryzicola of a number of 4-pyridone-3-carboxanilides with various substituents on the anilide and pyridone rings have been examined by use of physicochemical substituent parameters and regression analysis. The effects of substituents of the anilide ring were such that the activity was related parabolically not only with the substituent hydrophobicity (π) but also with the steric bulk parameter (Es) of the bulkier ortho substituent. The effect of substituents at the 1-position of the pyridone ring was analysed with steric(STERIMOL L and B5) and electronic(γ1) parameters. That of substituents at the 5-position of the pyridone ring was explained by a parabolic function of a steric (MR) parameter. Analyses of the activity of 105 analogs confirmed that our previous selection of a candidate compound in this series for field trials was indeed appropriate in terms of physicochemical substituent effects.  相似文献   
30.
To clarify the roles of granulated metrial gland (GMG) cells for successful pregnancy in rats, GMG cells in beige rats (genotype: DA-bg/bg), whose NK cells show lysosomal dysfunction because of abnormalities in cytoplasmic granules, were examined in mid- and late-pregnancy by light and electron microscopies. The GMG cells of beige rats were significantly less in number than those of the two controls (genotypes: DA-bg/+ and DA-+/+) in mid- and late-pregnancy, and this accompanied a low reproductive performance in the beige rats. The size of intracellular granules in the GMG cells of the beige rats was larger than for the two controls on each corresponding day of pregnancy. These results suggest that the activity of rat GMG cells and peripheral NK cells might be influenced by the beige gene, which is involved in reproductive performance.  相似文献   
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