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41.
The quality of shallow groundwater in the West Lake watershed was investigated from March to July 2000. Integrating with Blackland GRASS GIS system, the DRASTIC model was used to compile the groundwater vulnerability map. A land use factor was added to the DRASTIC model and the modified model (LDRASTIC) increased the accuracy of prediction from 26.9% to 51.3%. The vulnerability map showed that the lowly, moderately and highly susceptible area predicted occupied about 11.6%, 70.9% and 17.5% of the whole watershed, respectively. Compared with the observed values of nitrate and electric conductivity, the LDRASTIC index improved the Pearson correlation coefficients from -0.010 to 0.237 and 0.380 to 0.503;both the improved coefficients were significant at the 0.01 level. The modified DRASTIC analysis showed a great potential as a screening tool for policy decision-making in groundwater management.``  相似文献   
42.
The objectives of this study were to assess and compare the environmental impacts of two types of dairy farming systems, one of which makes use of whole‐crop rice silage and the other of which is conventional, using life cycle assessment (LCA). The functional unit was defined as 1 kg of 4% fat‐corrected milk (FCM). The processes associated with the dairy farming life cycle, such as feed production, feed transport, animal management including biological activity of the animal, and waste treatment were included within the system's boundaries. Environmental impacts of the rice silage‐using and conventional dairy farming systems were 987 and 972 g CO2 equivalents for global warming, 6.87 and 7.13 g SO2 equivalents for acidification, 1.19 and 1.23 g PO4 equivalents for eutrophication, and 5.53 and 5.81 MJ for energy consumption, respectively. Our results suggest that the dairy farming system using rice silage in Japan has smaller environmental impacts for acidification, eutrophication, and energy consumption, and a larger impact for global warming compared with conventional farming. Further interpretation integrating these impact categories suggested 1.1% lower environmental impact of the rice silage‐using dairy farming system as a whole.  相似文献   
43.
The waxy mutant wheat Tanikei A6599‐4 contains little amylose and exhibits a stable hot paste viscosity. It has null alleles at the Wx‐A1 and Wx‐B1 loci and a mutated allele at the Wx‐D1 locus (Wx‐D1e). From the cross‐combination of Kanto 123 (normal amylose line) and Tanikei A6599‐4, 51 DH (doubled haploid) lines were produced and their genotypes were determined by SDS‐PAGE and a derived cleaved amplified polymorphic sequence (dCAPS) analysis. Eight genotypes were obtained at the expected ratio. Using a Rapid Visco Analyser (RVA), all the lines with the same genotype as Tanikei A6599‐4 showed a stable hot paste viscosity. The other lines did not show a stable hot paste viscosity regardless of the presence of the Wx‐D1e allele. When two genotypes with the same Wx‐A1 and Wx‐B1 alleles were compared, the one with Wx‐D1e contained less amylose and exhibited a lower final viscosity and a lower setback with RVA. Although the Wx‐D1e allele produces an almost inactive Wx protein, these findings suggest that this allele contributes at some level to starch synthesis.  相似文献   
44.
The fates of more than 300 pesticide residues were investigated in the course of beer brewing. Ground malt artificially contaminated with pesticides was brewed via steps such as mashing, boiling, and fermentation. Analytical samples were taken from wort, spent grain, and beer produced at certain key points in the brewing process. The samples were extracted and purified with the QuEChERS (Quick Easy Cheap Effective Rugged and Safe) method and were then analyzed by LC-MS/MS using a multiresidue method. In the results, a majority of pesticides showed a reduction in the unhopped wort and were adsorbed onto the spent grain after mashing. In addition, some pesticides diminished during the boiling and fermentation. This suggests that the reduction was caused mainly by adsorption, pyrolysis, and hydrolysis. After the entire process of brewing, the risks of contaminating beer with pesticides were reduced remarkably, and only a few pesticides remained without being removed or resolved.  相似文献   
45.
Mammalian embryos are most commonly cryopreserved in liquid nitrogen; however, liquid nitrogen is not available in special environments, such as the International Space Station (ISS), and vitrified embryos must be stored at −80°C. Recently, the high osmolarity vitrification (HOV) method was developed to cryopreserve mouse 2-cell stage embryos at −80°C; however, the appropriate embryo is currently unknown. In this study, we compared the vitrification resistance of in vivo-derived, in vitro fertilization (IVF)-derived, and intracytoplasmic sperm injection (ICSI)-derived mouse 2-cell embryos against cryopreservation at −80°C. The ICSI embryos had lower survival rates after warming and significantly lower developmental rates than the in vivo and IVF embryos. Further, IVF embryos had a lower survival rate after warming, but a similar rate to the in vivo embryos to full-term development. This result was confirmed by simultaneous vitrification of in vivo and IVF embryos in the same cryotube using identifiable green fluorescent protein-expressing embryos. We also evaluated the collection timing of the in vivo embryos from the oviduct and found that late 2-cell embryos had higher survival and developmental rates to full-term than early 2-cell embryos. Some early 2-cell embryos remained in the S-phase, whereas most late 2-cell embryos were in the G2-phase, which may have affected the tolerance to embryo vitrification. In conclusion, when embryos must be cryopreserved under restricted conditions, such as the ISS, in vivo fertilized embryos collected at the late 2-cell stage without long culture should be employed.  相似文献   
46.
Nitroguanidine derivatives with thiazol-5-ylmethyl moieties were prepared and their insecticidal activities against homopterous pests were tested. New synthetic routes for 2-chloro-5-chloromethylthiazole from 2,3-dichloro-1-propene and for substituted nitroguanidines from S-methyl-N-nitroisothiourea were established. Biological evaluation led to a novel insecticide (E)-1-(2-chlorothiazol-5-ylmethyl)-3-methyl-2-nitroguani dine (TI-435) which has a broad activity spectrum and is under development. ©1999 Society of Chemical Industry  相似文献   
47.
Improving productivity is an urgent issue in the swine industry if it is to compete internationally. However, lack of data about recent productivity transition obstructs stakeholder planning. This study investigated the yearly productivity trends among farrow-to-finish swine farms in Japan using annual productivity data from 2013–2018 obtained for 70 farms in Japan. The productivity parameters analyzed were pigs born alive per litter (PBA), preweaning mortality (PRWM), pigs weaned per litter (PWL), litters per mated female per year (LMFY), pigs weaned per mated female per year (PWMFY), post-weaning mortality (POWM) and marketed pigs per mated female per year (MP). Data were classified into three groups based on the size of the average female inventory and compared among groups. Results presented the mean PBA increased continuously over the 6-year period (P<0.001), and the PWL, PWMFY, and MP means began increasing after 2015 (P<0.001). These upward trends were particularly remarkable on large farms. The mean PRWM increased sharply in 2014, thus inhibiting the increases in PWL, PWMFY, and MP for the same year. The LMFY and POWM means did not change during the study period. Altogether, productivity in Japan improved markedly during the study period, indicating highly prolific sows were well utilized with suitable breeding techniques among farmers these days. Continued genetic improvement and sow management would aid further development in Japan.  相似文献   
48.
Here, we performed next-generation sequencing (NGS) on six large flying foxes (Pteropus vampyrus) collected in Indonesia. Seventy-five virus species in the liver tissue of each specimen were listed. Viral homologous sequences in the bat genome were identified from the listed viruses. This finding provides collateral evidence of viral endogenization into the host genome. We found that two of the six specimens bore partial sequences that were homologous to the plant pathogens Geminiviridae and Luteoviridae. These sequences were absent in the P. vampyrus chromosomal sequences. Hence, plant viral homologous sequences were localized to the hepatocytes as extrachromosomal DNA fragments. Therefore, this suggests that the bat is a potential carrier or vector of plant viruses. The present investigation on wild animals offered novel perspectives on viral invasion, variation, and host interaction.  相似文献   
49.
The ICR-derived glomerulonephritis (ICGN) mouse, a new inbred mouse strain with a hereditary nephrotic syndrome, is considered to be a good model of human idiopathic nephrotic syndrome and notably exhibits proteinuria and hypoproteinemia from the neonatal stage. In chronic renal disorder (CRD), anemia is a major subsequent symptom (renal anemia). The precise cause of renal anemia remains unclear, primarily owing to the lack of appropriate spontaneous animal models for CRD. To establish adequate animal models for anemia with CRD, we examined the hematological-biochemical properties and histopathological characteristics. With the deterioration of renal function, ICGN mice developed a normochromic and normocytic anemia, and exhibited normochromic and microcytic at the terminal stage. The expression of erythropoietin (EPO) mRNA both in the kidneys and liver and the EPO leak into the urine were observed in ICGN mice, indicating a disrupted metabolism of EPO in ICGN mice. In addition, a lack of iron induced by the hemolysis in the spleen and the leak of transferrin into urine as proteinuria aggravated the anemic condition. In conclusion, the ICGN mouse is a good model for anemia with CRD.  相似文献   
50.
Among food allergens of tree nuts, walnuts are a frequent cause of adverse food reactions in allergic patients. A novel sandwich enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of walnut soluble proteins in processed foods was developed. The sandwich ELISA is highly specific for walnut soluble proteins. The recovery ranged from 83.4 to 123%, whereas the intra- and interassay coefficients of variation were less than 8.8 and 7.2%, respectively. This study showed that the proposed method is a reliable tool for detection in the presence of hidden walnut proteins in processed foods.  相似文献   
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