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31.
We intensively surveyed the concentrations of chemical species in aerosols and gases using a four-stage filter-pack method at a site in Japan facing the Sea of Japan in winter with 6-h sample intervals. A few chloride species emitted anthropogenically were detected, and the HCl (g) concentration was quite low. The number of chloride species artifacts was also low. The HNO3 (g) concentration was significantly higher when the monitored air mass passed over the Korean Peninsula compared to when it did not pass over the Korean Peninsula. In addition, the HNO3 (g) concentration was significantly higher when the air mass arrived at the monitoring site by passing the route at lower latitude than the latitude of the monitoring site. On the other hand, the SO2 (g) concentration showed no change between various trajectories of the air mass. The $ {\text{NH}}^{ + }_{4} $ (p)/non-seasalt- (nss-) $ {\text{SO}}^{{2 - }}_{4} $ (p) ratio was intermediate between the compositions of (NH4)2SO4 and NH4HSO4 when the air mass passed over the Korean Peninsula, whereas it was intermediate between NH4HSO4 and H2SO4 when the air mass did not pass over the Korean Peninsula. We detected the transboundary transport of sulfur dioxide with high time-resolution monitoring at two separate monitoring points: the current monitoring site and Oki Island.  相似文献   
32.
Night break treatment was applied to Eustoma grandiflorum ‘Nail Peach Neo’ using light sources with different red (R: 660 ± 30 nm): far-red (FR: 730 ± 30 nm) ratios or FR light intensities in order to investigate growth and flowering responses. Flower initiation and induction were promoted by night break treatment with a low R:FR light source, but was delayed by a high R:FR ratio. The promotion or delay of flower bud formation was accompanied by a decrease or an increase, respectively, in the number of nodes on the main stem at anthesis to the first floret. The difference between date of visible bud with plants under night break treatment and that of the control was approximated with high accuracy by a sigmoid function of the logarithms of R:FR ratio. The threshold R:FR ratio demarcating the promotion and delay of date of visible bud was about 5.3 under the experimental conditions used. The critical R:FR ratios for promotion or delay of visible bud would be about 0.5 and 50.0, respectively. In addition, the time from planting to visible bud was approximated with an exponential function of FR light intensity. The maximum acceleration of date of visible bud by long-day treatment would be 20 days, and the critical FR light intensity would be 2.0 μmol m−2 s−1. It is concluded that growth and flowering of E. grandiflorum can be regulated by long-day treatment using light sources with different R:FR ratios or FR light intensities.  相似文献   
33.
In the present study, we investigated the histological, immunohistochemical and ultrastructural characteristics of cytoplasmic blood plasma inclusions that spontaneously occurred in a rat liver. Histologically, a number of cytoplasmic inclusions were observed in the liver of an 8-week-old female SD rat. These inclusions were strongly positive for PAS staining and resistant to diastase digestion. Immunohistochemical analyses revealed that these inclusions were positive for albumin and IgG; however, most of them were negative for LAMP-1 and LAMP-2. Ultrastructurally, the inclusions were surrounded by limiting membranes and composed of moderately electron dense, homogenous materials. These characteristics described here represent valuable information for pathological examination in toxicity studies.  相似文献   
34.
Miniature Ping (mPing) is the first active miniature inverted-repeat transposable element to be identified in rice, and its mobilization is activated by stress treatments. We have examined the mobilization of mPing in four NERICA (New Rice for Africa) lines and 13 interspecific lines. All 17 lines are inbred progenies derived from crosses between Oryza sativa variety WAB56-104 as the recurrent parent and the O. glaberrima variety CG14 as the donor parent. We found that 16 of the 17 lines studied inherited mPing together with its autonomous partner, Pong, from WAB56-104. Transposon display of mPing disclosed polymorphic banding patterns among these lines. Most importantly, seven of the lines displayed clear polymorphic banding patterns for mPing, indicating that mPing might have been mobilized in these lines. Locus-specific PCR analysis also confirmed the mobilization of mPing. These results signify that interspecific hybridization may activate the transposition of mPing. Based on these results, we discuss the potential use of the mPing system as an efficient tool for gene tagging in interspecific hybrid rice.  相似文献   
35.
A confirmatory scan for the regions of bovine chromosome 1 segregating the quantitative trait loci (QTL) influencing birthweight, weaning weight, yearling weight, and preweaning and postweaning average daily gains was performed by genotyping half‐sib progeny of four Japanese Black sires using microsatellite DNA markers. Data were analyzed by generating an F‐statistic every 1 cM on a linkage map by the regression of phenotype on the probabilities of inheriting an allele from the sire after adjusting for the fixed effects of sire, sex, parity and season of birth as well as age as a covariate. Permutation tests at chromosome‐wide significance thresholds were carried out over 10 000 iterations. A significant QTL for birthweight at 114 cM was detected in the sire 2 family. This identification of a birthweight QTL in Japanese Black cattle may be useful for the implementation of marker‐assisted selection.  相似文献   
36.
Black soybeans have been used as a food source and also in traditional medicine because their seed coats contain natural phenolic compounds such as proanthocyanidin and anthocyanin. The objective of this research is to reveal the genetic variation in the phenolic compound contents (PCCs) of seed coats in 227 black soybean cultivars, most of which were Japanese landraces and cultivars. Total phenolics were extracted from seed coats using an acidic acetone reagent and the proanthocyanidin content, monomeric anthocyanin content, total flavonoids content, total phenolics content, and radical scavenging activity were measured. The cultivars showed wide genetic variation in PCCs. Each of the contents was highly correlated with one another, and was closely associated with radical scavenging activity. PCCs were also moderately associated by flowering date but not associated by seed weight. Cultivars with purple flowers had a tendency to produce higher PCCs compared with cultivars with white flowers, suggesting that the W1 locus for flower color can affect phenolic compound composition and content. Our results suggest that developing black soybean cultivars with high functional phenolic compounds activity is feasible.  相似文献   
37.
Cultivated soybeans (Glycine max) are derived from wild soybeans (Glycine soja) and can be crossed with them to produce fertile offspring. The latter exhibit greater genetic variation than the former, suggesting a possibility that wild soybeans contain storage proteins with properties different from and better than those of cultivated soybeans. To identify a wild soybean suitable for breeding a new soybean cultivar, we analyzed seed proteins from 390 lines of wild soybeans by electrophoresis. We found some lines containing electrophoretic variants of glycinin and beta-conglycinin subunits: one line containing a small alpha' subunit of beta-conglycinin and two and five lines containing small A3 and large A4 polypeptides of glycinin, respectively. Beta-Conglycinin and glycinin containing such variant subunits exhibited solubility and emulsifying ability similar to those of the predominant types of wild and cultivated soybeans. Glycinins containing small A3 and large A4 gave a shoulder derived from the start of denaturation at a temperature 4 degrees C lower than that of glycinin from the predominant types of wild and cultivated soybeans, although their thermal denaturation midpoint temperatures were very similar to each other. Cloning and sequencing of the predominant and variant subunit cDNAs revealed that the small alpha' and the small A3 lacked 24 amino acid residues in the extension region and four amino acid residues in the hypervariable region, respectively, and that the large A4 did not have an insert corresponding to the difference in the electrophoretic mobility but Arg279 and Gln305 were replaced by glutamine and histidine, respectively, in the hypervariable region. These suggest that small differences even in the hypervariable region can affect the thermal stability, as well as the electrophoretic mobilities, of the proteins.  相似文献   
38.
The detection and mapping of segregating quantitative trait loci (QTL) that influence withers height, hip height, hip width, body length, chest width, chest depth, shoulder width, lumbar width, thurl width, pin bone width, rump length, cannon circumference, chest girth, abdominal width and abdominal girth at weaning was conducted on chromosomal regions of bovine chromosome one. The QTL analysis was performed by genotyping half‐sib progeny of five Japanese Black sires using microsatellite DNA markers. Probability coefficients of inheriting allele 1 or 2 from the sire at specific chromosomal locations were computed. The phenotypic data of progeny were regressed on these probability coefficients in a within‐common‐parent regression analysis using a linear model that included fixed effects of sex, parity and season of birth, as well as age as a covariate. F‐statistics were calculated every 1 cM on a linkage map. Permutation tests of 10 000 iterations were conducted to obtain chromosome‐wide significance thresholds. A significant QTL for chest width was detected at 91 cM in family 3. The detection of this QTL boosts the prospects of implementing marker‐assisted selection for body conformation traits in Japanese Black beef cattle.  相似文献   
39.
A simulation analysis and real phenotype analysis were performed to evaluate the impact of three different relationship matrices on heritability estimation and prediction accuracy in a closed‐line breeding of Duroc pigs. The numerator relationship matrix (NRM), single nucleotide polymorphism (SNP)‐based genomic relationship matrix (GRM) (GS), and haplotype‐based GRM (GH) were applied in this study. We used PorcineSNP60 genotype array data (38 114 SNPs) of 831 Duroc pigs with four selection traits. In both heritability estimation and prediction accuracy, the accuracy depended on the number of animals with records. For heritability estimation, a large difference in the results among three relationship matrices was not shown, but the trend of the estimated heritabilities between GRMs, that is GS < GH, was shown in this population. For the accuracy of prediction values in test animals, the accuracies of prediction values obtained by two GRMs were higher than that by the NRM in this population. The accuracies obtained by GRMs using animals with no records were lower than that by the NRM using animals with their performance records, but were close to that by the NRM using animals with full‐sib testing records.  相似文献   
40.
Gassericin A, a bacteriocin produced by Lactobacillus gasseri LA39, has a cyclic structure linking N‐ and C‐terminal amino acids. Gassericin A was expressed in Escherichia coli JM109 as a biotinylated fusion protein on the basis of the DNA sequence of mature bacteriocin. A positive clone accumulated the bacteriocin, with no activity, as a soluble fusion protein in the cytoplasm. After release of an N‐terminal tag with factor Xa protease, gassericin A was converted into an active peptide having N‐ and C‐termini. The total amount of purified bacteriocins (expressed and native) was 480 µg/L and 370 µg/L, respectively. However, the specific activity of expressed gassericin A was 15 AU/mg lower than that of native bacteriocin (2600 AU/mg). Although the actual Mr (molecular weight) of the expressed bacteriocin should be 5666, the peptide showed the same mobility (Mr 3800) in sodium dodecylsulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) as native cyclic gassericin A, suggesting that the expressed peptide retains compact folding of the molecule similar to that of native gassericin A.  相似文献   
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