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171.
Seiichiro Yonemura Isamu Nouchi Seiichi Nishimura Gen Sakurai Kazuki Togami Kazuyuki Yagi 《Biology and Fertility of Soils》2014,50(1):63-74
No-tillage (NT) management is a promising method to sequester soil C and mitigate global warming caused by agricultural activities. Here, we report 4 years of continuous soil respiration rates and weekly nitrous oxide (N2O) and methane (CH4) emissions in NT and conventional-tillage (CT) plots in a typical Japanese volcanic soil. Overall, the soil respiration, N2O emission, and CH4 uptake decreased significantly in the NT plot. A difference in soil respiration and N2O emission between the two plots began after the tillage treatment and the incorporation of crop residues and fertilizers, whereas the CH4 uptake did not vary significantly during the fallow period after the treatments. The N2O emission was higher from the CT than from the NT plot during the fall. The overall lower CH4 uptake in the NT than in the CT plot likely resulted from a combination of decreased soil gas diffusivity and higher mineral N content at the soil surface. Higher soil respiration and N2O emission occurred in the NT plot in the summer of 2003 and were plausibly caused by an increase in the soil moisture content that resulted from lower temperatures during July and August; the higher soil moisture must have accelerated the decomposition of organic matter accumulated in the topsoil. These results indicate that NT management is generally effective for the mitigation of the total GWP by reducing soil respiration and N2O emission in temperate regions; however, NT management may increase rather than decrease these emissions when fields experience cool summers with frequent rainfall. 相似文献
172.
Tumor necrosis factor (TNF)-alpha is thought to be one of the cytokines that account for bovine leukemia virus (BLV)-induced B-cell lymphoproliferative disorder, however, information on TNF-alpha expression in B-cells is limited. In this study, the expression of TNF-alpha in IgM(+) B-cells from BLV-infected sheep with or without lymphocytosis was determined. Freshly isolated IgM(+) B-cells from three sheep with lymphocytosis constitutively transcribed TNF-alpha mRNA. Although TNF-alpha mRNA expression in IgM(+) B-cells was transiently up-regulated after cell culture, TNF-alpha mRNA expression was markedly higher in lymphocytotic sheep when compared to that of non-lymphocytotic sheep or uninfected sheep. Expression of membrane-bound TNF-alpha on IgM(+) B-cells was also augmented in lymphocytotic sheep. TNF-alpha expression in lymphocytotic sheep may support the proliferation of B-cells. 相似文献
173.
This paper reports on a study comparing three spectroscopic measurements (interactance, reflectance, and transmittance) in the Vis/NIR range for the detection of internal insect infestation with different damaged levels in jujubes (Hovenia acerba Lindl.). Stepwise discriminant analysis was used to derive the discriminant functions based on the effective wavelengths that had maximum discriminatory potential for the different internal conditions. The results show that both interactance in the long-wave NIR (LWNIR) and transmission in the visible and short-wave near-infrared (VSWNIR) wavelength ranges have an obvious advantage over reflectance for every range in completely distinguishing infested from intact jujubes. However, interactance and reflectance in the VSWNIR wavelength range exhibited higher classification accuracies in sorting severely damaged jujubes from slightly infested and intact samples. Furthermore, transmission had clear advantages over both interactance and reflectance for distinguishing slightly infested jujubes from intact jujubes in the VSWNIR range. 相似文献
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Tran TU Suzuki K Okadome H Ikezaki H Homma S Ohtsubo K 《Journal of agricultural and food chemistry》2005,53(4):1108-1118
Changes in the taste of japonica, hybrid, and indica brown and milled rice, stored for 10 months at low (5 degrees C, 65-70% relative humidity) and room temperatures were observed by physicochemical analyses and a novel method using a taste sensing system. During storage, some properties increased or decreased while others were fairly constant. The main taste components of cooked rice such as sweetness (sucrose) and umami tastes (glutamic acid and aspartic acid) were reduced during storage, whereas glucose and fructose increased. The increase of fat acidity and consequent decrease of the pH value of the cooking solution may contribute to the off-taste of cooked stored rice. A taste sensing system with 10 lipid membrane sensors was also used to classify new and old rice samples using principal component analysis. Fresh and room temperature stored japonica and indica rice could be clearly distinguished; however, it was not possible to differentiate the samples stored at low temperature. 相似文献
177.
Wen X Enokizo A Hattori H Kobayashi S Murata M Homma S 《Journal of agricultural and food chemistry》2005,53(7):2684-2689
ApV is a brownish polymer with zinc-chelating activity in brewed coffee. We investigated in this study the effects of roasting on the zinc-chelating, reducing, and antioxidative activities of ApV from light-, medium-, and dark-roasted coffee. We also discuss the effect on the zinc-chelating activity of adding milk to the brewed coffee. The chelating activities of ApVs were evaluated by the tetramethyl murexide method. As the intensity of roasting increased, the yield of ApV increased, and the brown color and molecular weight of ApV respectively became darker and higher. Increasing the degree of roasting also decreased the zinc-chelating activity of ApV. The reducing activities of ApVs estimated by the indophenol method were stronger than those of ascorbic acid. Both the antioxidative activity estimated by the ABTS assay and the reducing activity of ApV increased with roasting. When milk was added to instant coffee and its ApV was prepared, the zinc-chelating activity of ApV was not changed. 相似文献
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Tanaka S Mannen K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):351-354
Butorphanol tartrate (BT) was injected into mice before injection with acetylcholine in a murine model infected latently with pseudorabies virus. The analgesic effect and its influence on virus reactivation were observed. Mice preinjected with BT showed suppression of screaming, moving and excitation and the same level of movement after excitation as mice injected with PBS. In the group injected with BT i.p., one mouse died and another developed diarrhea with increased virus excretion. These results showed that BT has analgesic effects by both injection routes, s.c. and i.p.; however, BT induced death as a side effect, especially with i.p. injection. The injection route for BT should therefore be investigated further. 相似文献