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The effect of the application of acidified porous hydrate calcium silicate (APS) in nursery bed soil and porous hydrate calcium silicate (PS) in paddy fields on the growth of rice plants ( Oryza sativa L. cv. Hitomebore) was examined in 2002 and 2003. The results revealed the following: 1) Shoot dry weight of rice seedlings increased by APS treatment in nursery bed soil. The tiller number of rice plants after transplanting in both years also increased by APS treatment in nursery bed soil, and in 2003, the tiller number in the treatment with a combination of APS in nursery bed soil and PS in paddy fields was significantly higher than that in the other treatments until the maximum tiller number stage. Furthermore, the root length of rice plants 14 d after transplanting increased by APS treatment in nursery bed soil. 2) Silicon concentration in the soil solution significantly increased by PS treatment in paddy fields, and the concentration of dissolved carbon oxide increased by APS treatment in nursery bed soil. 3) Only in the APS treatment the rice yield was 341 g m−2, while 400 and 450 g m−2 in the PS and both APS and PS treatments, respectively, in 2003. Percentages of ripened grains in the plots without PS treatment ranged from 57 to 63%, respectively, while, those in the PS treated plots were 82%. The numbers of panicles and ripened grains in both APS and PS treatments were the highest among the treatments. Based on the above results, we concluded that both APS in nursery bed soil and PS in paddy field treatments were effective in improving the silicon nutrition and growth of rice plants, and that this effect was enhanced by a combination of treatments with the two.  相似文献   
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The contributions of cation exchange and mineral weathering to the neutralization of acidity in the Jingahata watershed in central Japan were estimated through a laboratory weathering experiment and runoff chemistry measurements. The laboratory experiment was conducted in a stirred-flow reactor for a whole soil sample collected from the C horizon in the watershed. The concentration ratios of base cations (Ca2+, Mg2+, K+ and Na+) to Si (BC/Si) released during the steady-state stage of the laboratory experiment were in good agreement with the ratios of the net flux of base cations to the flux of Si in the streamwater (BC N ET/Si L).This result suggests that the acidity in the watershed is neutralized primarily by mineral weathering without causing a net loss of base cations from exchange sites. The alkalinity/acidity balance estimated for the watershed shows that the total weathering rate of base cations is approximately 3.26 keq ha?1 yr?1. Weathering of plagioclase (An41) contributes 83% of the total weathering rate. The dominant acidity source is CO2 released within the soil horizons, accounting for roughly 85% of the total acidity flux (3.20 keq ha?1 yr?1). This high internal production of acidity suppresses the relative importance of atmospheric acidity inputs (0.3 keq ha?1 yr?1).  相似文献   
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In this study were successfully observed the one- (1H, 13C) and two-dimensional (1H-13C, 1H-15N, 1H-31P) NMR spectra of milk directly without any pretreatment. The signals of each NMR spectrum were assigned, and their existing states were also analyzed. Lactose existed in a free state in milk. The signals due to the butyric acid chain can be assigned among the other fatty acid chains. Monounsaturated fatty acid (oleic acid chains) and polyunsaturated fatty acid chains (linoleic and linolenic acid) were assigned by their characteristic signals. The signals from citrate, N-acetylcarbohydrates, and lecithin could be observed directly in the 1H-13C HSQC NMR spectra; the assignment of their signals was made through the 1H-13C, 1H-15N, and 1H-31P HMBC spectra of extracted milk. Signals from creatine and N-acetylcarbohydrates were detected for the first time.  相似文献   
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Acanthocephalan everted cystacanths were detected in the intestines of 61 out of 555 feral raccoons (Procyon lotor) trapped between May 2003 and April 2005 in the western region of mainland Japan (Honshu). All collected specimens were identified as the species of birds including 3 Centrorhynchus species (C. bazaleticus, C. elongatus, and C. teres), Sphaerirostris lanceoides, Plagiorhynchus ogatai, Porrorchis oti, and Southwelina hispida. Three species, C. bazaleticus, C. teres, and S. lanceoides, were new to distribution records in Japan and the Far East. Recovery rates of these acanthocephalans were higher from the raccoons trapped in spring and early summer (range 8.3-36.8%, average 21.5%) than during the remainder of the year (range 0-20.0%, average 6.3%). The reason for this seasonal change is unknown. There is little information on the acanthocephalan fauna of wild birds in Japan, however, recovery of the cystacanths from the feral raccoons captured through the year might provide useful information on the fauna and geographical distribution of avian acanthocephalans.  相似文献   
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A new bacterial black spot disease was observed on Odontoglossum, Odontioda, Odontocidium, and Vuylstekeara orchids in Japan. Typical symptoms on the leaves were dark or black spots (or both) with a yellow halo. The causal agent was identified as Burkholderia andropogonis (Smith 1911) Gillis, Van Van, Bardin, Goor, Hebbar, Willems, Segers, Kersters, Heulin and Fernandez 1995. The isolates were pathogenic on four original host orchids, Phalaenopsis orchid, and tulip; they were not pathogenic on white clover or corn after needle stab inoculation. An antibiotic bactericide (oxytetracycline/streptomycin mixture WP) was most effective for controlling the disease.  相似文献   
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Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high‐density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep.  相似文献   
40.
Conserving pig genetic resources and improving their productivity is important to increase returns over investment in developing countries. The purebred, first‐cross, rotational cross and backcross matings representing production systems based on pig breeds indigenous to the country and exotic pig breeds were investigated. The number of pigs in the nucleus and commercial herds necessary to produce a defined quantity of pork was considered. The amount of heterosis between the indigenous and exotic breeds, superiority in meat production, and degree of inferiority in reproductive performance of the exotic breed compared with that of the indigenous breed were investigated. The number of breeding pigs in the whole system was in the following order: pure breeding (PB) > first‐cross (F1) > rotational cross (RC) > backcross (BC) systems. The number of breeding pigs in the nucleus herds of the RC and BC systems was smaller than that in the nucleus herds of the PB and F1 systems. The degree of inferiority in reproductive performance of the exotic breed compared with that of the indigenous breed affected the efficiency of the production system.  相似文献   
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