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Promoting biomass utilization, the objectives of this study were to clarify the spatial distribution of nitrogen, one of the most important fertilizer components in the methane fermentation digested slurry (i.e., the digested slurry), and to establish an effective method to apply spatial-uniformly digested slurry with irrigation water in the rice paddy field. A numerical model describing the unsteady two-dimensional flow and solution transport of paddy irrigation water was introduced. The accuracy of this model was verified with a field observation. The tendencies of the TN simulated in inlet and outlet portions had good agreement with the measured data and the accuracy of the numerical model could be verified. Using the numerical model, scenario analyses were conducted to determine the method for spatial-uniform application of the digested slurry with irrigation water. The simulated results indicated that drainage of the surface water and trenches at the soil surface were effective for spatial-uniform application of the digested slurry with irrigation water in the rice paddy fields. The effect of the trenches was maximized when the surface water of the rice paddy field was drained adequately.  相似文献   
23.
Nine Suffolk sheep and 4 Holstein cattle were employed to observe electroencephalographic changes in experimental cerebrocortical necrosis. Amprolium (600 mg/kg/day) alone was given intraruminally 6 sheep and 4 cattle, all of which showed neurological signs and abnormal electroencephalograms. Both amprolium and thiamine (200 mg/day) and thiamine (50 mg/day) alone were given 2 and 1 sheep, respectively, as controls, which did not show any abnormal signs. Abnormal electroencephalograms included continuous slow waves and long-lasting spindles, both of which appeared diffusely and were seen subclinically or with neurological signs. The spindles consisted of slow waves or sharp- (or spike-) and-slow-wave complexes with or without convulsive seizures even during the convulsion stage. Conversely, the seizures occurred with the spindles or slow waves.  相似文献   
24.
Copper plates were exposed under shelters at 13 sampling sites in East Asia and their corrosion was analyzed. The corrosion products were first dissolved in water and then oxalic acid. Sulfate, nitrate and chloride in the solutions were measured by ion chromatography. The amounts of the three anions significantly differed depending on the atmospheric environment at the sites. Sulfate was a major part of the anions at Chongqing and Shanghai in China. Especially, at the urban sites in Japan, nitrate remarkably changed with the seasons, and often became the large anionic component in the summer. The amounts of chloride at most sites were at higher concentration levels compared with those at the rural sites in Japan. The anions in the copper corrosion must mainly reflect the impact of acid deposition.  相似文献   
25.
通过温室盆栽试验 ,分析和探讨了三个水平的土壤水分条件对分蘖期和成熟期收获的旱稻(OryzasativaL .)生物量累积、水分利用率 (WUE)、植株不同部位的碳同位素识别值 (CID)的影响 ,并了解了它们之间的相互关系。水分条件包括 :饱和含水量 (W1 )、饱和含水量的 70 %(W2 )、饱和含水量的 4 0 %(W3)。结果表明当土壤水分条件从W1降低到W2时 ,分蘖期收获的生物量降低 4 5 %左右 ,成熟期收获的生物量降低 1 6 %~ 1 9%;而当从W1降低到W3时 ,分蘖期收获的生物量降低 73%左右 ,成熟期收获的生物量降低 5 5 %~ 5 7%。然而 ,根据地上部干重计算而来的WUE(WUE 地上部 )和根据全株干重计算而来的WUE(WUE 全株 )则随土壤含水量的降低而增加 ,其增幅在分蘖期为 0 .0 7~ 0 .2 8gkg-1 ,在成熟期为 0 .0 7~ 0 .4 5gkg-1 。植株的CID值变幅为 1 7.0~ 2 0 .6 ,但植株不同部位间差别显著 ,分蘖期收获的样品CID值从小到大的顺序为 :根 <最近完全伸展叶 <叶芽 <茎秆 ;而成熟期收获的样品CID值从小到大的顺序为 :籽粒 <根 <茎秆 <旗叶。随着土壤含水量的降低 ,植株所有部位的CID值亦显著减小。叶部的CID值与WUE 地上部(和WUE 全株 )之间呈一致的负相关关系。  相似文献   
26.
Self-regulating systems often use robust oscillatory circuits. One such system controls the chemotactic signaling mechanism of Dictyostelium, where pulses of adenosine 3',5'-monophosphate (cAMP) are generated with a periodicity of 7 minutes. We have observed spontaneous oscillations in activation of the mitogen-activated protein (MAP) kinase ERK2 that occur in phase with peaks of cAMP, and we show that ERK2 modulates cAMP levels through the phosphodiesterase RegA. Computer modeling and simulations of the underlying circuit faithfully account for the ability of the cells to spontaneously generate periodic pulses during specific stages of development. Similar oscillatory processes may occur in cells of many different species.  相似文献   
27.
Variants of NOD2, an intracellular sensor of bacteria-derived muramyl dipeptide (MDP), increase susceptibility to Crohn's disease (CD). These variants are thought to be defective in activation of nuclear factor kappaB (NF-kappaB) and antibacterial defenses, but CD clinical specimens display elevated NF-kappaB activity. To illuminate the pathophysiological function of NOD2, we introduced such a variant to the mouse Nod2 locus. Mutant mice exhibited elevated NF-kappaB activation in response to MDP and more efficient processing and secretion of the cytokine interleukin-1beta (IL-1beta). These effects are linked to increased susceptibility to bacterial-induced intestinal inflammation and identify NOD2 as a positive regulator of NF-kappaB activation and IL-1beta secretion.  相似文献   
28.
Effects of soybean hull water-soluble hemicellulose (WSHC) on serum immunoglobulin (Ig) concentration and production of NO and IL-1beta from peritoneal macrophages were examined and compared with those of Agaricus blazei in the rat system. WSHC consisted of arabinose, galactose, xylose, glucose, and rhamnose, and the molecular weight was approximately 500000. Rats were ip administrated each sample at a dose of 0.67, 13.4, or 26.9 mg/kg/day for 14 days. The administration of WSHC resulted in significantly higher productions of IgM (p < 0.01 on day 6, p < 0.05 on day 14) and IgG (p < 0.05 on day 6) than those in other groups. When peritoneal macrophages were stimulated with various concentrations of sample (0.67, 13.4, or 26.9 mg/mL), WSHC significantly increased both NO and IL-1beta productions only at the concentration of 13.4 (mg/mL) compared with those of a saline group. These findings demonstrate that WSHC enhances humoral immunity and activation of macrophages, thereby leading to the augmentation of immune responses in rats.  相似文献   
29.
A nested air quality prediction modeling system (NAQPMS) has been developed to investigate the various processes that govern the loading of chemical species and anthropogenic aerosols at various scales of atmospheric motions in urban and regional scales. The model employs flexible horizontal grid resolution with multiple multi-level nested grids with options for one-way and two-way nesting procedures in a spherical and terrain-following coordinate. The NAQPMS is driven using meteorological fields from the NCAR/Penn State Fifth-Generation Mesoscale Model (MM5). Hourly pollutant levels of 71 stations covering Taiwan are used to evaluate the modeling system. Case simulation of a high-ozone episode occurred during April 13–15 1999 shows that the technique of the model nesting is capable of affording more realistic temporal and spatial structures of concentration fields, processes and precursors.  相似文献   
30.
An oligonucleotide complementary to a leader RNA of positive-stranded mouse hepatitis virus (MHV) was tested for the effect on the viral multiplication in mouse DBT cells. A 14-mer antisense oligonucleotide contained a sequence complementary to the conserved pentanucleotide sequence, UCUAA, of the leader RNA. A treatment of MHV-infected cells with the antisense oligonucleotide at concentrations from 5 to 25 microM had an inhibitory effect on the viral multiplication and reduced the synthesis of viral specific mRNA and proteins. No inhibitory effect was observed when the cells were treated with sense oligonucleotide and oligonucleotide which contained unrelated sequences at concentrations from 1 to 10 microM. These results showed that antisense oligonucleotide against the leader RNA reduced the multiplication of positive-stranded RNA virus, MHV.  相似文献   
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