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61.
Phosphoglucoisomerase (PGI) was studied to establish the genetic system of the isozymes in section Cepa of Allium. The results of isozyme analyses using 15 cultivars and clones in two cultivated species A. fistulosum and A. cepa, eight strains in four wild species A. altaicum, A. galanthum, A. oschaninii and A. vavilovii and a total of 10 hybrids between A. fistulosum and A. cepa and between the cultivated and wild species revealed that: 1) PGI was a dimeric enzyme; 2) the two cultivated and four wild species had a common gene locus Pgi-1 where six alleles were identified; and 3) A. fistulosum had Pgi-1 F-1 and Pgi-1 F-2, A. cepa had Pgi-1 A-1 and Pgi-1 A-2, A. altaicum had Pgi-1 F-1, A. galanthum and A. vavilovii had Pgi-1 A-1, and A. oschaninii had Pgi-1 A-1, Pgi-1O-1 and Pgi-1 O-1. The intra- and inter-specific polymorphisms of PGI isozymes are expected to be valuable tools for the genetics and practical utilization of the wild species in section Cepa.  相似文献   
62.
The present study examined the Serum 3-methylhistidine concentrations and energy-associated variables of 5 healthy Holstein cows and 5 Holstein cows with ketosis. The serum total cholesterol and apolipoprotein B-100 concentrations and lecithin-cholesterol acyltransferase (LCAT) activity of the ketotic cows were lower than those of the healthy cows 14 days before parturition. The serum non-esterified fatty acid (NEFA) concentration on the day of parturition and 3-methylhistidine concentration 14 days after parturition were higher in the ketotic cows. The serum 3-methylhistidine concentration 14 days after parturition was negatively correlated with the serum LCAT activity 14 days before parturition and was positively correlated with the serum NEFA concentration on the day of parturition. Insufficiency of cholesterol metabolism and acceleration of body fat degradation occur before parturition in cows with ketosis, and these characteristics are correlated with acceleration of protein degradation after parturition.  相似文献   
63.
The accident at the Fukushima Daiichi Nuclear Power Plant (FNPP) released a large amount of radioactive substances into the environment. Furthermore, beef contaminated with radioactive cesium above the 500 Bq/kg safety standard was circulated in the food chain in 2011. Japanese consumers remain concerned about the safety of radioactively contaminated food. In our previous study, we detected a linear correlation between radioactive cesium (137Cs) activity in blood and muscle around 500 to 2500 Bq/kg in cattle. However, it was unclear whether the correlation was maintained at a lower radioactivity close to the current safety standard of 100 Bq/kg. In this study, we evaluated 17 cattle in the FNPP evacuation zone that had a 137Cs blood level less than 10 Bq/kg. The results showed a linear correlation between blood 137Cs and muscle 137Cs (Y = 28.0X, R2 = 0.590) at low radioactivity concentration, indicating that cesium radioactivity in the muscle can be estimated from blood radioactivity. This technique would be useful in detecting high‐risk cattle before they enter the market, and will contribute to food safety.  相似文献   
64.
15 years ago an interim report for an intense environmental program was compiled concerning the location of the islands of Japan at the meteorological down stream of the East Asian Countries. Parts of sulfur dioxide and other air pollutants, those supposed to cause acid deposition are emitted from the eastern parts of the Asian continent, especially in China. The air pollutants flow down to the east to spread over these islands. This acid deposition is projected to cause damage to forest resources of Japan in the future by increasing air pollutants emanating from the continent. A long term project by a research group at Keio University commenced in 1985 to identify ways of preventing this damage to the forests. The group formed the JACK Air Surveillance Network in China and South Korea in order to collect the first precise air pollution data in this region, as well as to identify a reliable partner for the project. On the completion of the JACK project, a highly cooperative group was formed between the researchers of Keio University and those in Chengdu, Sichuan province of China and has effectively worked since 1991. The goal of the project is the formation of an Inland Environmental Information Center in inland China to be accomplished by 2005. To launch a 10 year project by the center, a nation wide campaign is planned to raise the awareness of the population, specifically the lower socio-economic group on the effect of environmental issues. It is suggested that this education campaign take effect in inland China no later than 2025 for the preservation of the forests on the Islands of Japan.  相似文献   
65.
Habitat structure in Oku-Nikko, Japan, has been substantially modified by the overabundance of sika deer (Cervus nippon). A deer-proof fence (15.0 km and 900 ha) was constructed in 2001 to conserve vegetation. Although the understory inside the fence is dominated by Sasa nipponica (hereafter, Sasa), an important forage plant for deer, that outside the fence is dominated by Aster ageratoides leiophyllus (hereafter, Aster), an unpalatable plant to deer, and, partly, by bare floor. In this study, we examined the effects of deer on ground-dwelling insects and earthworms, the primary food resources of raccoon dogs (Nyctereutes procyonoides), and, thus, the bottom-up cascading effects of the herbivore on the omnivorous carnivore. Between July and September 2008, we examined the abundance of insects and earthworms by pitfall trapping and hand-sorting methods, respectively, both inside and outside the fence. The abundance of earthworms and insects (Scarabaeidae and Rhaphidophoridae) was higher on forest floors with Aster and/or bare floors outside the fence than on those with Sasa inside the fence. These results indicate that the increasing deer population in this area probably increased the number of these invertebrates outside the fence by modifying understory vegetation and/or depositing dung. Furthermore, the sighting rates of raccoon dogs obtained by spotlight counts were greater outside than inside the fence, suggesting that deer probably exert bottom-up cascading effects on raccoon dogs, at least during May to November, when the invertebrates are predominantly fed on by the omnivorous carnivore.  相似文献   
66.
Two taurine breeds, Japanese Black and Holstein, established from geographically distant origins and selected for different uses, beef and dairy, were extensively genotyped using a genome‐wide single nucleotide polymorphism (SNP) chip with more than 1000 animals of each breed. The genetic structure was examined by principal component analysis, in which the first principal component clearly separated the two breeds and explained more than 15% of the variance. Highly differentiated SNPs were detected throughout the genome, some of which were clustered within small regions on BTA4 (79.2–79.7 Mb, Btau4.0) and BTA26 (22.2–23.6 Mb). A breed assignment test was developed using 18 highly differentiated SNPs to distinguish Japanese Black from F1 (Japanese Black × Holstein) and Holstein. The error rate that an F1 or Holstein animal is misjudged as Japanese Black was expected to be < 0.8%, while the error rate that a Japanese Black animal is misjudged as F1 or Holstein was expected to be < 0.001%. This test provides a reliable and powerful method to detect breed label falsification in retail beef.  相似文献   
67.
In June 2006, a large number of small black spots containing a branching network of black hyphae developed on shipped Satsuma mandarin fruits grown in greenhouses, which markedly decreased their commercial value. The fungus that was frequently isolated from the damaged fruits was identified as Cladosporium cladosporioides. Inoculation of fruits with the fungus caused the same symptoms, and the fungus was reisolated from the diseased fruits. The disease caused by this fungus has not been previously documented in citrus fruits; we name this new disease “sooty spot” on the basis of its symptoms.  相似文献   
68.
69.
The water chemistry of 51 headwater streams was studied in the Tanzawa Mountains, western fringe of Southern Kanto Plain, Japan. The relationships to soil N processes and catchment topography were also evaluated using a geographic information system with fine-scale map data. The average concentration of total dissolved N was 0.74 mg-N L−1, of which 95% consisted of NO3 -N. Stream N concentrations were not different among bedrock geologies and among vegetations of the catchments. Stream NO3 -N marginally correlated to soil nitrification. Stream NO3 -N also tended to be high in areas with steep and south-facing slopes. These results imply that N transport from Tanzawa forest ecosystems is related to hydrological and biological processes associated with catchment topography. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
70.
More than 200,000 tons of scallop shells are disposed annually alone in Japan. Nanoparticles derived from scallop shells have the potential to adsorb gaseous formaldehyde; therefore, such discarded shells have now been tested as additive filler in plywood adhesive by mixing high specific surface area, urea-modified shell nanoparticles with a resorcinol–formaldehyde resin. With this procedure, it was found that the emission of formaldehyde from the resulting plywood could be substantially reduced. The urea-modified scallop shell nanoparticles were prepared by two different methods: (1) a dry method where the shells were treated by planetary ball-grinding under ambient conditions—a completely dried powder was obtained after addition of the surface-modifying urea solution; (2) a moist method by treating dry ground shell particles in a wet grinding process with the urea solution, followed by centrifugation to obtain a paste. The specific surface area of the nanoparticles obtained by both treatments was 42 ± 3 m2/g. Measurement of the subsequent formaldehyde emission showed that the addition of the modified scallop shell nanoparticles substantially reduced the formaldehyde emission from plywood. The reduction of the specific mass uptake of urea depends on the nanoparticles which especially was the case when resins containing nanoparticles processed by the moist method were used.  相似文献   
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