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41.
Paddy and Water Environment - In recent years, Paddy Field Dams have received recognition as a measure to alleviate flooding due to torrential rains. Paddy Field Dams have been in practice in...  相似文献   
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43.
Caulogenic calli with a high differentiation potency were induced from mature embryos ofPicea jezoensis seeds stored over a long time, for 29 years, resulting in the active formation of adventitious buds. Embryos began to induce calli within 3 weeks of cultivating on LP medium containing 3 μM BAP and 1 μM 2,4-D. Then, the calli proliferated and transformed into caulogenic calli with bud primordia in 8 weeks. The caulogenic calli increased actively with the addition of 500 mg/l ofl-glutamine in the medium. Furthermore, caulogenic calli, induced on LP medium containingl-glutamine, resulted in the formation of adventitious buds, which elongated after transferring the calli into LP medium with 0.1 μM BAP, but withoutl-glutamine. It appears that the number of adventitious buds and the process of shoot elongation are influenced by the kind of nitrogen contained in the medium for callus induction. A part of this study was presented at the 107th Annual Meeting of the Japanese Forestry Society (1996).  相似文献   
44.
We exposed momi fir (Abies firma Sieb. et Zucc.) seedlings to simulated acid fog of pH 3.0 for about 3 years (from July 1999). During the last year of acid fog exposure, half of the seedlings were subjected to rhizosphere Al stress (complex stress) and the nutrient status of seedlings was determined. Chronic acid fog exposure decreased Fe and Zn concentrations in current-year and 1-year needles, and Al in 1-year needles, but had little effect on major element concentrations. Aluminum treatment had a broad impact on nutrient status in fine roots and needles. In fine roots, increases in Al and Cu concentrations and decreases in B, Mn, and Zn concentrations were observed. In 1-year needles, Al treatment increased Al, B, and Mn concentrations and decreased Cu concentration. The complex effect of acid fog with aluminum on nutrient status was relatively slight. These results show that changes in nutrient status under chronic acid fog exposure and/or Al stress are induced before the decline of photosynthesis in momi fir seedlings, mainly due to Al stress.  相似文献   
45.
The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000 in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production of good quality somatic embryos in P. densiflora.  相似文献   
46.
Reaction between maleic anhydride (MA) and wood specimens was carried out in a vapor phase reaction system. Reaction conditions such as the ratio of supplied MA to wood, initial moisture content, and reaction temperature were optimized. The MA supplied to the reaction system was effectively absorbed by the wood, and a satisfactorily high dimensional stability was achieved even at a low MA/wood ratio. The dimensional stability increased with rising initial moisture content. When the reaction was conducted at an elevated temperature (180°C), high dimensional stability was attained without remarkable weight increase and bulking. The mechanism of dimensional stabilization was discussed on the basis of the dimensional changes at high humidity and during repeated water soaking and drying. It was shown that the dimensional stabilization arises mainly from a decrease of hygroscopicity. When the reaction was conducted at 180°C, the formation of cross-links in the cell wall was apparent. Following the MA treatment, the antifungal property was remarkably enhanced and met the Japanese Industrial Standard K1571. Therefore, MA treatment in the vapor phase is an effective method to attain antifungal properties as well as high dimensional stability with a small amount of nontoxic reagent.  相似文献   
47.
In a previous paper we presented the efficacy of the extended distinct element method (EDEM) on the collapsing process simulation of timber-frame structures. The results obtained were qualitative, and the need for quantitative simulation was pointed out. In this report, we improved our simulating programs with the aim of establishing a quantitative simulation by EDEM. For this purpose, the parameters of the frame members (beam or column) were determined by comparing the simulated results of four-point bending tests with experimental results. Other parameters of plywood and joint members were determined by simulations of two rail shear and slip tests of joint parts, respectively. Using these parameters we made simulations of the collapsing process of an actual-size plywood-sheathed wall and at the same time carried out the experiments under similar conditions. Simulated load–displacement curves of the plywood-sheathed wall were similar to those obtained in the experiments, and the sequence of failure at nailed joints of the simulation model gave good agreement with that of the experimental collapsing processes. Using these processes, we believe that we established a basic quantitative simulation method to test the collapsing process of timber-frame structures.Part of this paper was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002; and at the 7th World Conference of Timber Engineering, Malaysia, August 2002  相似文献   
48.
The storage of spent maitake culture medium (SMCM) under various conditions was investigated as a potential pretreatment of SMCM for increased ethanol conversion. When SMCM was stored at 25°C for 12?weeks, the glucose yield by enzymatic saccharification increased from 22 to 52%. Selective degradation of lignin and hemicellulose occurred in SMCM during storage. The optimal storage temperature of SMCM was at the active growing temperature of maitake mycelium, which is between 25 and 30°C. Storage of SMCM under anaerobic conditions did not increase the glucose yield compared to non-stored conditions. The glucose yield from the SMCM stored for 4?weeks at 25°C was increased by about 30% with either NaOH or vibrating ball milling pretreatment. After 12?weeks of storage, the glucose yield from SMCM without any other pretreatment was higher than that of non-stored SMCM with additional pretreatments. An ethanol yield of 42.1% was obtained from SMCM stored for 12?weeks by simultaneous saccharification and fermentation, which was comparable to yields after NaOH (41.3%) or vibrating ball milling (44.1%) pretreatments. Therefore, storage of SMCM is a very useful pretreatment for bioethanol production.  相似文献   
49.
Canine osteoarthritis occurs frequently and causes secondary synovitis. Administration of nonsteroidal anti-inflammatory drugs (NSAIDs) is one of the major therapeutic options for pain management of joint diseases. Tepoxalin has an unique property as an NSAIDs that suppresses both cyclooxygenase and lipoxygenase. The purpose of this study was to evaluate antiproliferative effects of tepoxalin on cultured canine synovial cells. Cytotoxic effects of tepoxalin, carprofen, meloxicam and AA-861 on cultured canine synoviocytes were evaluated by MTT colorimetric assay. Apoptosis was detected by morphological observations with Giemsa or annexin V/Hoechst 33342 staining and by the inhibition of caspase-3 activity with N-Ac-Asp-Glu-Val-Asp-CHO (Ac-DEVD-CHO). Cytotoxic effects of tepoxalin were evident in comparison with the effects of carprofen or meloxicam. The same tendency of cytotoxicity was observed when 5-lipoxygenase was inhibited by AA-861. The morphological findings and contradictory effects of Ac-DEVD-CHO with regard to the cytotoxicity proved the proapoptotic effects of tepoxalin. In conclusion, tepoxalin might control osteoarthritic synovitis by inducing apoptosis in proliferating synoviocytes, while most NSAIDs that selectively inhibit cyclooxygenase-2 most likely would not suppress synovial proliferation.  相似文献   
50.
OmpL1 is a 31-kDa outer membrane protein characterized in 1993 and known to be expressed only in pathogenic Leptospira spp. Recombinant OmpL1 (GST-rOmpL1) was expressed for use as an ELISA antigen for the detection of anti-Leptospira antibodies. In immunoblot analysis, the protein reacted with sera of dogs infected with three different serotypes of Leptospira interrogans, while did not react with sera of dogs both uninfected negative controls and infected with Borrelia burgdorferi, which is closely related to Leptospira spp. Moreover, in ELISA using GST-rOmpL1, the optical density (O.D.) values from the positive controls were very high (1.125 +/- 0.549). In contrast, the O.D. values from clinically healthy dogs and dogs with diseases other than leptospirosis were very low (0.109 +/- 0.046 and 0.089 +/- 0.046, respectively). These data suggest that the detection of anti-Leptospira antibodies by ELISA using the GST-rOmpL1 protein can be applied for diagnosis of canine leptospirosis.  相似文献   
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