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排序方式: 共有221条查询结果,搜索用时 15 毫秒
11.
Anim Boanyo?DansohEmail author Akio?Koizumi Takuro?Hirai 《Journal of Wood Science》2003,49(5):405-410
A study was undertaken to evaluate the effect of glue application and placement of butt-joints on the compressive and tensile properties in a butt-jointed lamination. The aim was to provide background information for producing butt-jointed, glued, laminated timber. Three butt-jointed lamination models were prepared from spruce-pine-fir (S-P-F) dimension lumber with glued and nonglued butt joints, with different placements of the butt joints in the models. The axial stiffness and strength properties were assessed using both compressive and tensile tests. The results of the study indicated that for the compressive lamination model the application of glue at the butt joint gave more stiffness than the nonglued butt joint. Neither glue application nor placement of the joint had a statistically significant effect on the compressive strength. There were no significant differences between the glued and nonglued butt joint for either tensile strength or stiffness. 相似文献
12.
Takashi?KamiyamaEmail author Hiroyuki?Yamauchi Takuro?Iwai Shoichi?Hanawa Yukihiko?Matsuyama Satoshi?Arima Yuichi?Kotani 《Fisheries Science》2005,71(6):1295-1303
ABSTRACT: Sea water environmental conditions over annual cycles were investigated and compared between two oyster farming areas, western Hiroshima Bay and Oginohama Bay (a branch of Ishinomaki Bay) in Miyagi Prefecture, to appropriately manage oyster culture or more efficiently utilize farming areas. The environmental parameters of temperature, salinity, nutrient concentrations (NO2 –N, NO3 –N, NH4 –N, PO4 –P, and SiO2 –Si) and size-fractionated chlorophyll- a (<0.2, 2–20, >20µm), and abundances of microzooplankton were measured in each bay at the surface, and 2 and 5 m depth layers. Differences in the annual mean values and results with monthly paired Student's t -tests showed that salinity was lower, and temperature, nutrient (especially PO4 –P) and chlorophyll- a concentrations, and abundance of microzooplankton, were higher in Hiroshima Bay than in Oginohama Bay. Differences in environmental conditions between inshore and offshore areas of each bay suggest that inflows of river water in western Hiroshima Bay and sea water from offshore had the most significant effects on the environmental conditions. It is concluded that such oceanographic and biological differences strongly affect the oyster farming system, especially regarding the optimum usage of offshore areas in Summer under clean, cold and stable seawater conditions, rather than food quantity in Hiroshima Bay, and under more abundant food conditions in Oginohama Bay. 相似文献
13.
14.
Zhang Chengming Nobuhiro Tanaka Maria Stefanie Dwiyanti Matthew Shenton Hayato Maruyama Takuro Shinano Chu Qingnan Xie Jun Toshihiro Watanabe 《水稻科学》2022,29(1):76-88
Ionomic profiles are primarily influenced by genetic and environmental factors. Identifying ionomic responses to varietal effects is necessary to understand the ionomic variations among species or subspecies and to potentially understand genetic effects on ionomic profiles. We cultivated 120 rice (Oryza sativa) varieties to seedling stage in identical hydroponic conditions and determined the concentrations of 26 elements (including 3 anions) in the shoots and roots of rice. Although the subspecies effects were limited by the genus Oryza pre-framework and its elemental chemical properties, we found significant differences in ionomic variations in most elements among the aus, indica and japonica subspecies. Principal component analysis of the correlations indicated that variations in the root-to-shoot ionomic transport mechanisms were the main causes of ionomic differences among the subspecies. Furthermore, the correlations were primarily associated with the screening of varieties for elemental covariation effects that can facilitate breeding biofortified rice varieties with safe concentrations of otherwise toxic elements. The japonica subspecies exhibited the strongest elemental correlations and elemental covariation effects, therefore, they showed greater advantages for biofortification than the indica and aus subspecies, whereas indica and aus subspecies were likely safer in metal(loid) polluted soils. We also found that geographical and historical distribution significantly defined the ionomic profiles. Overall, the results of this study provided a reference for further association studies to improve the nutritional status and minimize toxicity risks in rice production. 相似文献
15.
A Hashimoto M Takiguchi K Hirai H Kida L E Carmichael 《The Japanese journal of veterinary research》2001,49(3):249-253
A serological survey for antibodies to minute virus of canines (MVC) by use of a hemagglutination-inhibition (HI) test was performed on sera collected from dogs in the Tokai area of Japan. Forty-one of 266 (15.4%) sera had positive titers of 1:40 or higher against the MVC. Results suggest that MVC may have been present in dogs in Japan since, at least, 1990. From this serosurvey, MVC appears to be established in the dog population in Japan. MVC may have a role as a newly recognized viral pathogen of dogs in Japan. 相似文献
16.
Summary Soybean DNA fingerprints were analyzed by digoxigenin-labeled oligonucleotide probes complementary to simple repetitive sequences. The clearest and most polymorphic patterns were obtained with (AAT)6 as a probe, with which all 47 soybean cultivars tested could be distinguished. However, DNA fingerprints of individuals within cultivars showed the same pattern. Using (CT)8, (GAA)5 or (AAGG)4 as probes, clear polymorphic patterns among cultivars and accessions in the subgenus Soja (Glycine max and Glycine soja) were not observed, while quite different patterns were found in accessions in the subgenus Glycine. The results suggest that G. max and G. soja are closer in their genome structure. DNA fingerprints of reciprocal crosses between cultivars and accessions in the subgenus Soja were similar, and contained bands of both parents. In an F2 population from these crosses, such bands segregated in a Mendelian fashion. 相似文献
17.
Nitrogen-fixing activity in decomposing litter of three tree species at a watershed in eastern Japan
Takashi Yamanaka Keizo Hirai Shuhei Aizawa Shuichiro Yoshinaga Masamichi Takahashi 《Journal of Forest Research》2011,16(1):1-7
Nitrogen fixation during litter decomposition was studied for 34 months using litterbags containing newly fallen litter of
coniferous species Cryptomeria japonica and Pinus densiflora and that of deciduous species Quercus serrata. Litterbags were set in contact with the forest floor in a deciduous broad-leaved forest near the top of a slope and in a
C. japonica stand at the middle of the slope at a watershed in eastern Japan. Nitrogen-fixing activity, estimated by acetylene reduction
after 16 and 19 months of incubation, was 62.65–3.86 nmoles C2H4 h−1 g−1 DW in Cryptomeria litter, but only 1.07–0.09 in Pinus and 0.72–0.04 in Quercus. The rate of N increase in decomposing litter was highest in Cryptomeria. Fungal biomass in decomposing litter, estimated by ergosterol content, increased during the initial 16 months of incubation
in Cryptomeria and Quercus, and during the initial 19 months of incubation in Pinus. The litter decomposition rate was highest in Cryptomeria among the three species, due to increased N content and fungal biomass in Cryptomeria litter. Thus, N increase in decomposing Cryptomeria litter affects the subsequent N dynamics and decomposition pattern. 相似文献
18.
To evaluate windthrow resistance with respect to stem breakage, a nondestructive method for determining the shape of trunk
cross sections was developed. In this method, the coordinates of multiple gauge points set on the perimeter of a trunk are
calculated by measuring the distances between them. The shape between the gauge points is generated with the use of a profile
gauge placed between them. Measurement tests were conducted using profile gauges with lengths of 300 and 900 mm on model specimens
with four shape patterns and four different diameters. The accuracy of the estimation was verified by comparing the section
modulus calculated for the generated image and for the photograph. The average ratio of section modulus (generated/photo)
for all specimens was 0.994, which indicates that the proposed method is highly accurate. The section moduli of hollow trunks
can be evaluated using the profile method together with the drill resistance technique on the condition that 26% of the trunk
diameter could be drilled without skew. 相似文献
19.
The behavioral function of a pheromone released by males of the army-worm moth Pseudaletia unipuncta was investigated both in laboratory wind-tunnel experiments and in experiments with moth-baited traps in the field. Such male moth scents have been thought to act at close range as sexual stimulants for females of the same species. However, the only obvious effect of the P. unipuncta male pheromone was upon other males, decreasing their tendency to approach sexually receptive, pheromone-releasing females and to exhibit copulatory behavior when near those females. The adaptive significance of the male pheromone may be related to the increased reproductive efficiency that results if multiple males are prevented from competing for a single female. 相似文献
20.
Asagiri M Hirai T Kunigami T Kamano S Gober HJ Okamoto K Nishikawa K Latz E Golenbock DT Aoki K Ohya K Imai Y Morishita Y Miyazono K Kato S Saftig P Takayanagi H 《Science (New York, N.Y.)》2008,319(5863):624-627
Cathepsin K was originally identified as an osteoclast-specific lysosomal protease, the inhibitor of which has been considered might have therapeutic potential. We show that inhibition of cathepsin K could potently suppress autoimmune inflammation of the joints as well as osteoclastic bone resorption in autoimmune arthritis. Furthermore, cathepsin K-/- mice were resistant to experimental autoimmune encephalomyelitis. Pharmacological inhibition or targeted disruption of cathepsin K resulted in defective Toll-like receptor 9 signaling in dendritic cells in response to unmethylated CpG DNA, which in turn led to attenuated induction of T helper 17 cells, without affecting the antigen-presenting ability of dendritic cells. These results suggest that cathepsin K plays an important role in the immune system and may serve as a valid therapeutic target in autoimmune diseases. 相似文献