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81.
Kano R Kudo A Kamiya H Kobayashi Y Maeda R Omata Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(10):1095-1097
To clarify the role of progesterone in the development of immune responses during pregnancy against Neospora caninum infection, C57BL/6 mice were given a progesterone pellet, and measured on Interferon-gamma and interleukin-4 production following the infection. IFN-gamma production in the prescribed group was significantly lower than that in the intact group on day 40 post administration. IL-4 producing cell population in the prescribed group was larger than that in the intact group. These results suggest that progesterone may alter the balance of cytokine production, and that the bias toward type 2 immune response may remain for a certain period after the infection. 相似文献
82.
Hikaru Kitahara Yoichi Okura Toshiaki Sammori Akiko Kawanami 《Journal of Forest Research》2000,5(4):231-236
Universal Soil Loss Equation (USLE), originally developed by the USDA for agricultural lands and then used throughout the
world, was applied in mountainous forest terrain in Japan. The slope length and steepness factors were extended for long slope
lengths and steep slopes by recalculating the data from available literature in Japan and by using data from supplementary
erosion experiments. As such, we conclude that the USLE can be used successfully to estimate surface erosion on long, steep
mountainous forest slopes. The cover and management factors of many kinds of natural and artificial forest stands, cutting
types, and disturbance regimes were calculated from the literature. The support practice factors of many types of soil and
water conservation practices were also calculated from published information. Based on these results, we showed that the USLE
can be applied to estimations of soil erosion from wide areas including many kinds of agricultural and forest lands.
This study was funded by the Agricultural, Forestry, and Fishery Technology Council Office for comprehensive studies on agriculture,
forestry, and fisheries and the agricultural, forestry, and fishery trading, resources, and environments. 相似文献
83.
Several previous studies in Japan have examined differences in rainfall interception amounts induced by differences in forest properties by comparing the annual rainfall interception ratios (annual rainfall interception divided by annual rainfall) from various sites without considering variations in meteorological conditions between sites. Rainfall interception actually depends on meteorological conditions as well as forest properties. This study examined variations in the annual interception ratio relating to the variation in annual rainfall, which would be the primary factor relating to the interception ratio, across Japan with the use of a rainfall interception model assuming the same forest properties (i.e., the canopy storage capacity, canopy closure, leaf area index (LAI), and the bulk coefficient for sensible heat transfer). The ratio ranged between 0.12 and 0.24 across Japan and was highly correlated to annual rainfall. This indicates that considering the variation in annual rainfall is critical for assessing the difference in rainfall interception amounts induced by forest properties. We reconsidered the results of previous studies in Japan that compared annual interception ratios between sites with different forest properties: (i) there is no clear difference in interception amounts between broadleaf and coniferous forests and (ii) there is a positive correlation in stem density and interception amounts for coniferous forests. These results still held when considering differences in annual rainfall between sites. 相似文献
84.
Yoichi Kojima Ayaka Kawabata Hikaru Kobori Shigehiko Suzuki Hirokazu Ito Rie Makise Masaki Okamoto 《Journal of Wood Science》2016,62(6):518-525
Wood-based materials are fabricated with adhesives composed of various materials derived from fossil fuels. It is difficult to identify replacements for these chemical adhesives. This study explored nanofiber technologies as an alternative to these adhesives. In this study, we focused on reinforcement effects of lingo-cellulose nanofiber (LCNF) on fiberboards made from softwood and hardwood fiber. We discuss the density effects of reinforcement with LCNF because the density of medium-density fiberboard (MDF), which is widely used for construction, is standardized at about 0.60–0.80 g/cm3. Fiberboards were manufactured with three densities (0.60, 0.75, and 1.00 g/cm3). For softwood fiberboards, the bending properties for LCNF-mixed boards were higher than those for the control fiberboards at all densities. In this paper, control fiberboard means fiberboard with fiber only. For hardwood fiberboards, the bending properties for LCNF-mixed fiberboard for 1.00 g/cm3-density board were higher than those for the control fiberboard. For internal bond strength (IB), the IB for LCNF-mixed fiberboard was higher than that for the control fiberboard. The thickness swelling (TS) and weight change (WC) with water absorption for fiberboards containing LCNF were lower than those for control fiberboards. As a conclusion, physical and mechanical properties of the resulting fiberboards were significantly improved with the addition of LCNF, especially for softwood fiberboards, due to close binding between LCNF and wood fibers. 相似文献
85.
Masanobu Ohshiro Ichiro Nakamura Hikaru Akamine Masanobu Tamaki Prasanta Chitta Bhowmik 《Plant Production Science》2016,19(1):61-72
Soil types and fertilizer regimes were evaluated on growth, yield, and quality of Amaranthus tricolor lines, IB (India Bengal), TW (Taiwan), BB (Bangladesh B), and BC (Bangladesh C) in developing management practices in Okinawa. Growth and yield of all amaranth lines were higher in gray soil (pH 8.4) than in dark red soil (pH 6.6) and red soil (pH 5.4). The combined NPK fertilizer resulted in highest growth parameters and yield of amaranths in all soils. Nitrogen fertilizer alone did not affect growth parameters and yield of amaranths in dark red and red soils. Growth parameters and yield increased similarly with the 30, 40, and 50 g m?2 of NPK fertilizer in BB line, and with the 20, 30, 40, and 50 g m?2 in BC line. Agronomic efficiency of NPK fertilizer at 50 g m?2 was not prominent on the amaranths, compared to the fertilizer at 40 g m?2. Amaranth lines had higher Na in dark red and red soils, while K and Mg in gray soil, Ca in gray and red soils, and Fe in dark red soil. The NPK fertilizer resulted in higher Na, Ca, Mg, and P in BB line in glasshouse. These minerals in BB line were not clearly affected, but in BC line were lower with NPK fertilizer at 20–50 g m?2 in field. These studies indicate that gray soil is best for amaranth cultivation and combined NPK fertilizer at 20–40 g m?2 is effective in gray soil in Okinawa for higher yield and minerals of amaranth. 相似文献
86.
87.
The color of Undaria pinnatifida after boiling is an important factor determining its marketable value. Our previous study showed that decreased nutrients and elevated irradiance resulted in increases of lightness and yellowness (i.e., discoloration) of this alga. However, little is known about the optimal levels of nutrients and irradiance required to decrease these color values and the combined effects of these factors and boiling. We conducted two culture experiments to test the effects of nutrients (non-enriched and 1.25, 5, and 25% PESI enriched treatments), irradiance (0, 10, 30, and 180 µmol m?2 s?1), and boiling on lightness L*, redness a*, and yellowness b* of this alga. L* and b* did not differ between non-enriched and 1.25–5% PESI treatments, but were lower in the 25% PESI treatment. L* and b* were lowest at 0–10 µmol m?2 s?1, although negative growth occurred at 0 µmol m?2 s?1. Decreased irradiance had a positive or little effect on a* before boiling, but had a negative effect after boiling. These results suggest that around 25% PESI and 10 µmol m?2 s?1 were the optimal levels to decrease the three color values of this species after boiling. 相似文献
88.
This study examined the effects and optimal conditions of double heat‐shock treatment (HST) for the suppression of cleavage in fertilized willow minnow (Gnathopogon caerulescens) eggs. In addition, we performed a cytological analysis of the nucleus and mitotic apparatus dynamics before and after HST. Tetraploidy occurred at the highest frequency (45.4%) when the first HST was delivered 25 min after fertilization and the second 15 min later. In this group, the spindle atrophied immediately after completion of the second HST; subsequently, three distinct patterns were observed in the nucleus and mitotic apparatus of the first cell cycle. In the first pattern, one pole disappeared and a monopolar spindle formed; chromosomes were unable to separate and accumulated at one pole where they formed a large nucleus. In the second pattern, the poles were dispersed or localized to one side of the nucleus, resulting in the failure of chromosomes to separate and the formation of a single nucleus. In the third pattern, the first cleavage was completed normally. Thus, double HST can block the first cleavage division by eliminating one centrosome or bringing two poles close together, giving rise to a subset of tetraploid embryos. 相似文献
89.
长江三峡花岗岩坡面管流产流特性研究 总被引:19,自引:4,他引:19
含有大孔隙的土体 ,如花岗岩风化壳及其上形成的土层水分运动规律并不遵从达西定律 (Darcy L aw) ,大孔隙中运动的水流称为管流 (pipe flow)。在花岗岩地区 ,由于管流的普遍存在 ,从土壤剖面流出的水量远远超出在达西法则定义下流出的水量。为研究土壤水分渗透中非遵从达西定律的土管 (大孔隙 )管流运动规律 ,在位于长江三峡的湖北省秭归县花岗岩坡面进行了管流流量、坡面渗流、地表径流和降雨过程等项目的观测和研究。发现管流在该地区是一种普遍存在的现象 ,管流过程中的水分运动不遵从达西定律 ,其流量在坡面渗流中占的比重约为 10 %~ 30 % ,土管在土壤剖面中所占面积虽然很小 ,但其水分通量远大于相同降雨条件下的土壤剖面水分渗透通量。 相似文献
90.
Effects of oceanic-climate changes on the abundance of Pacific saury (Cololabis saira) in the northwestern Pacific during the last half century were investigated. Abundance indices of both large and medium size groups exhibit interannual–decadal variations, but their patterns were different. The large and medium size groups of saury are corresponding to the recruitments of winter- and spring-cohort, respectively. The abundance of large size group saury was significantly correlated with the winter sea surface temperature (SST) in the Kuroshio region, whereas the medium size group saury showed high correlations with SST in the Kuroshio–Oyashio transition zone and the Oyashio region, indicating that the two size groups are affected by subtropical and subarctic environment, respectively. Significant negative correlation between the abundance index and the southern oscillation index (SOI) suggested that El Niño-southern oscillation (ENSO) events have marked impacts on the large size group saury. Subtropical high pressure index and far east zonal index also show high correlations with the abundance of both large and medium size group saury, indicating a linkage between large-scale atmospheric circulation and the abundance of saury. These correlations demonstrate that the abundance of Pacific saury is directly affected by the SST fields through large-scale atmosphere–ocean interactions from the equatorial Pacific to mid- and high-latitude areas such as El Niño events. 相似文献