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1.
Journal of Plant Diseases and Protection - The antagonistic rhizobacterium, Pseudomonas fluorescens strain LRB3W1, controls cabbage Fusarium yellows caused by Fusarium oxysporum f. sp. conglutinans... 相似文献
2.
In Japan, the lifetime cycle of most housing lasts around 20–30 years. A governing factor in this respect is poor durability
due to old-fashioned use of the house. As a solution of this problem, houses can be built with a skeleton structure that allows
free partition of spaces by future owners. To develop the skeleton structure effectively, multistory frames with spans of
6 to 10 m are required. For this reason, attention has been focused on the behavior of multistory timber frame structures.
In this article, two types of wooden portal frame structures are proposed. Both structures have improved vertical columns
with short horizontal members glued in. The aim of this study was to investigate structurally effective solutions with these
types of columns. The first type of the new structure changed the location of the moment-transmitting ductile connection with
the improved columns. The second type of structure used an extended panel zone. Nine portal frame specimens were tested. The
stiffness values were improved by around 1.7 and 3.5 times when compared with the control, and the strength was improved by
around 1.25 and 1.45 times. 相似文献
3.
Spatially distributed morphological characteristics of macropores in forest soils of Hitachi Ohta Experimental Watershed, Japan 总被引:1,自引:0,他引:1
Shoji Noguchi Yoshio Tsuboyama Roy C. Sidle Ikuhiro Hosoda 《Journal of Forest Research》1997,2(4):207-215
Morphological characteristics of macropores in forest soil profiles were investigated at Hitachi Ohta Experimental Watershed
in Japan. Nine individual profiles at different locations (various spatial scales in a catchment) and twenty profiles at one
site (a small spatial scale) were excavated to the bedrock to investigate density, origin, diameter, direction, and gradient
of macropores. Macropore densities in a soil profile ranged from 3.5 to 29.1 per m and from 5.4 to 75.1 per m2, respectively. Subsurface erosion, root channels, and interactions between subsurface erosion and root channels accounted
for 36.9, 36.5, and 19.0%, of the described macropores. The mean macropore diameter in organic-rich soil layer (17–20 mm)
was larger than in the B horizon (11–14 mm) at both spatial scales. The dominant gradients of all macropores in the organic-rich
soil layer and B horizon were at negative oblique angles. Approximately 90% of the macropores in the organic-rich soil layer
and approximately 80% of the macropores in the B horizon fell within the range between −50 and 50 degree planar direction.
Subsurface flow and root systems are believed to play important roles in determining the morphological characteristics of
macropores. These characteristics appear to have variable influences in different soil horizons rather than at different spatial
scales.
A part of this paper was presented at the 103th (1992) and 105th (1994) Annual Meetings of Japanese Forestry Society. 相似文献
4.
Tomo’omi Kumagai Koichiro Kuraji Hironori Noguchi Yuri Tanaka Katsunori Tanaka Masakazu Suzuki 《Journal of Forest Research》2001,6(4):257-264
Environmental factors, such as global solar radiation, wind speed, air temperature, humidity, and CO2 concentration, were measured above and within the canopy of a tropical rainforest in Lambir Hills National Park, Sarawak,
Malaysia. Few data concerning the environment of this forest have been reported. Intensive observations were carried out in
1998, 1999, and 2000 with the following results: (1) The fraction of global solar radiation reaching the upper layer of the
canopy varied with global solar radiation above the canopy. Even though the global solar radiation above the canopy fluctuated,
the fraction of that reaching the lower canopy and the ground was constantly approximately 5%. (2) The fraction of wind speed
reaching each layer of the canopy increased with wind speed above the canopy. Little wind was usually present at the lower
canopy. (3) The daytime air temperature at the canopy top was higher than that near the ground. The maximum difference between
the air temperature at the canopy top and that at the ground was about 5°C, and the diurnal temperature ranges at the canopy
top and those at the ground were about 8°C and about 5°C, respectively. The highest daytime water vapor pressure occurred
within the canopy and particularly near the ground. Vertical gradients of water vapor pressure during the day were steep,
probably because of high transpiration. (4) In the 1998 observation the minimum and the maximum CO2 concentrations were 360 ppm in the day and 450 ppm at night, while in the 2000 observation the minimum and the maximum CO2 concentrations were 350 ppm in the day and 540 ppm at night. The higher CO2 concentration in the daytime and the lower concentration at night observed during the 1998 observation period were probably
due to reduced photosynthesis and soil respiration caused by exceptional dry conditions during the observation period. 相似文献
5.
Summary The acoustic emissions (AEs) under partially compression were monitored with two softwood and one hardwood specimens in very eary stages of decay by a brown- and a white-rot fungus. Even slightly decayed specimens emitted AEs immediately after beginning of loading, typically when partial compression stress was applied to brown-rotted wood with the flat-headed attachment. With sound specimens of three wood species, only a few AEs were generated until the load reached at the proportional limit. These results suggest that AE monitoring will be one of the feasible means to detect the incipient stages of decay in a field test.The authors thank the Weyerhaeuser Research Grants Program for its aid in this investigation 相似文献
6.
Kyotaro Noguchi Tadashi Sakata Takeo Mizoguchi Masamichi Takahashi 《Journal of Forest Research》2005,10(6):435-441
Fine roots are a key component of forested ecosystems, but available information is still limited. This study examined the
production and mortality of fine roots less than 1 mm in diameter in a Japanese cedar (Cryptomeria japonica D. Don) plantation located on the Kanto Plain in central Japan. We used a minirhizotron technique in combination with soil
coring, and collected data for 1 year (May 2002–May 2003). Fine root production and mortality were determined from changes
in the lengths of individual fine roots on minirhizotron tubes. Both fine root production and mortality rates were greater
in the upper soil than in lower soil levels. Both rates were seasonal, with higher values in summer than in winter; this trend
was more pronounced in upper soil levels. These results suggest that environmental conditions, such as temperature or soil
properties, affect the production and mortality rates of fine roots. Fine root production and mortality occurred simultaneously,
and their rates were similar, which may have led to unclear seasonal changes in fine root standing crop estimates. Soil coring
indicated that the fine root biomass of this stand was about 120 g m−2, of which 40% was from Japanese cedar. The estimated rates of dry matter production and mortality of total fine roots, including
understory plants, were both approximately 300 g m−2 year−1. 相似文献
7.
8.
The attracting effect of paralytic shell poison (PSP) on eight toxic snail species (Polinices didyma, Natica lineata, N. vitellus, Zeuxis sufflatus, Niotha clathrata, Oliva miniacea, O. mustelina, O. hirasei) and two non-toxic species (Pomacea canaliculata, Satsuma bairdi) was investigated. Eight toxic species were reported to contain tetrodotoxin, and three out of these contained minor PSP.
The minimum lethal dose of PSP in most toxic gastropods was estimated to be more than 150 MU PSP/20 g body weight, but in
non-toxic gastropods was less than 15 MU PSP/20 g body weight. After the attracting test, all toxic gastropods showed significant
positive linear relationship (Y=3.716X+0.363, r=0.8427) between comparative attracting variation and the toxicity reported. The relationship between PSP resistance ability
and the toxicity also had a positive correlation (Y=0.91X+210.090, r=0.6803). However, the non-toxic species showed a negative response. This indicates that PSP is an attractant for toxic snails. 相似文献
9.
10.
Toyoshima K Noguchi R Hosokawa M Fukunaga K Nishiyama T Takahashi R Miyashita K 《Journal of agricultural and food chemistry》2004,52(8):2372-2375
Sardine oil was obtained by centrifugation of surimi wastewater without heating or chemical refining. This oil (CE) showed light yellow color and the peroxide value was less than 1.0 meq/kg. The main lipid class of CE was triacylglycerol (TG) (>99%). These features indicate that CE can be directly used as food materials without further purification. Commercial sardine oil (CO) is usually prepared via some kind of refining process with high temperature (250 degrees C) and chemical treatment. The comparative study on the physiological effects of these sardine oils (CE and CO) revealed that the dietary sardine oils were more effective in reducing abdominal fat pads, plasma total cholesterol, and TG levels of rats than was a soybean oil diet (control). Furthermore, these effects were greater in CE than CO, although there was little difference in the fatty acid composition of both oils. Although the main lipid class of CE was TG (>99%), CE was prepared by centrifugation from surimi waste and directly used as dietary fat without further purification. Therefore, CE may contain some kinds of minor components, which could be attributed to the higher physiological activity of CE. To reveal the involvement of the minor compounds in CE, we prepared TG from CE by column chromatography and measured its effect on lipid metabolism of rats. TG from CE also showed the reducing effects on abdominal fad pads and plasma lipid levels. The effect of TG from CE was almost the same as that of original CE, suggesting that the higher nutritional activity of CE than CO may not be due to the minor compounds in CE. 相似文献