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81.
In this study, a forestry profit model for carbon dioxide (CO2) emission trading was constructed using southeast Georgia, USA, as the model area. The value of CO2 credits regarding forest stores of carbon was calculated using the stock changing method, the average storing method, the ton-year method, and the returning CO2 credit method. Based on this model, the CO2 price at which an afforestation interest rate reaches its maximum in each 5-year interval at a cutting age of 10–50 years was calculated, considering the influence on the cutting age by introducing emission trading. The cutting age at which an afforestation interest rate reaches its maximum was 32 years. The cutting age shortened with the rise of CO2 price in all four accounting methods. Assuming the dealing CO2 price, we can forecast what the present cutting age will be according to the stock changing method and the average storing method in regard to this model. Assuming this CO2 price and using the ton-year method and the returning CO2 credit method, we can forecast that the present cutting age is not going to change.  相似文献   
82.
83.
ABSTRACT: A facile synthesis of Tyrian purple, a valuable purple dye derived from gastropod mollusks in ancient times, has been accomplished. Tyrian purple, 6,6'-dibromoindigo, was easily obtained by three steps of reactions from the commercially available 6-bromoindole, on the basis of a biosynthetic pathway of indigo and biological precursors of the purple. Iodination of 6-bromoindole, followed by acetoxylation with silver acetate in acetic acid, afforded 6-bromo-3-acetoxyindole, whose alkaline hydrolysis accompanying air oxidation produced Tyrian purple.  相似文献   
84.
Organic-inorganic hybrid zeolite materials containing an organic framework have been synthesized by partially superseding a lattice oxygen atom by a methylene group. The use of methylene-bridged organosilane as a silicon source gives zeolite materials containing an organic group as lattice (ZOL), with several zeolitic phases such as the MFI and the LTA structures. Through various characterization methods, the presence of methylene frameworks (Si-CH2-Si) that replace siloxane bonds (Si-O-Si) has been verified, although the Si-C bonds are partly cleaved to give rise to terminal methyl groups. The shape-selective lipophilicity of a ZOL material indicates that it is not a physical mixture of conventional zeolite and amorphous organic-containing material but contains a genuine organic-inorganic hybrid zeolite.  相似文献   
85.
ABSTRACT:   Thirteen strains of labyrinthulids were isolated from the coastal area of Kagoshima Bay, Kagoshima Prefecture, Japan and from Batan Bay, Panay Island, the Philippines by using diatom double-layer agar plates. The cells of labyrinthulid isolates grew axenically on the dead bacterial cells and extract plus egg yolk agar medium (NSBEY agar). Three representative isolates were demonstrated to belong to the labyrinthulid phylogenetic group (LPG) based on 18S  rDNA sequence analysis. As bacteriolytic activity of labyrinthulid isolates was examined, it was found that they could lyze only the dead cells of gram-negative bacteria and not those of gram-positive bacteria during incubation in both agar and liquid media. The optimum temperature range for bacteriolysis was 25–31°C. Orange carotenoid pigment was accumulated during the stationary growth phase of strain 00-Bat-05, Philippine isolate, cultured in an L-shaped tube containing a bacterial dead cell suspension. Concomitant rapid cell movement of developing zoospores was observed.  相似文献   
86.
In this study, we compared the developmental ability of somatic cell nuclear transfer (SCNT) embryos reconstructed with three bovine somatic cells that had been synchronized in G0‐phase (G0‐SCNT group) or early G1‐phase (eG1‐SCNT group). Furthermore, we investigated the production efficiency of cloned offspring for NT embryos derived from these donor cells. The G0‐phase and eG1‐phase cells were synchronized, respectively, using serum starvation and antimitotic reagent treatment combined with shaking of the plate containing the cells (shake‐off method). The fusion rate in the G0‐SCNT groups (64.2 ± 1.8%) was significantly higher than that of eG1‐SCNT groups (39.2 ± 1.9%) (P < 0.05), but the developmental rates to the blastocyst stage of SCNT embryos per fused oocytes were similar for all groups. The overall production efficiency of the clone offspring in eG1‐SCNT groups (12.7%) per recipient cow was higher than that in G0‐SCNT groups (3%) (P < 0.05). The mean birth weight of cloned calves and the average calving score in the G0‐SCNT groups (48.1 ± 3.4 kg and 3.3 ± 0.3, respectively) was significantly higher (P < 0.05) than those of eG1‐SCNT groups (37.2 ± 2.1 kg and 2.3 ± 0.2, respectively). Results of this study indicate that synchronization of donor cells in eG1‐phase using the shake‐off method improved the overall production efficiency of the clone offspring per transferred embryo.  相似文献   
87.
Growth of the tumor autoinduced by 20-methylcholanthrene (MC) in rats was inhibited after administration of Toxoplasma lysate antigen (TLA). The antitumor activity of TLA was most obvious in the early stage of tumoral growth. When TLA was administered to rats before the appearance of tumour, tumor formation was delayed slightly. Histopathological studies revealed dense growths of spindle tumor cells in untreated control rat, while enlarged central necrosis with the infiltration of lymphocytes and neutrophils was apparent in TLA-treated rats. According to the immunohistological examination of tumor tissue with anti-Thy-1 antibody, the rats treated with TLA showed large Thy-1 positive granular cells, whereas the untreated rats indicated only a few small Thy-1 positive cells. These observations indicate that TLA is a useful modifier of biological responses to MC-induced tumors.  相似文献   
88.
A nationwide epidemiological survey of Babesia gibsoni infection in non-fighting dogs was conducted using an improved ELISA with recombinant B. gibsoni thrombospondin-related adhesive protein (BgTRAP). A total of 1206 dogs from 27 prefectures were examined and 128 (10.6%) tested positive. In the eastern part of Japan, 39 dogs out of the 559 (7.0%) examined were positive, while 89 dogs out of 647 (13.8%) tested positive in the western part of Japan. Although the percentage of dogs that tested positive was significantly (p=0.0001) lower in the eastern part compared to the western part of Japan, overall these results indicate that B. gibsoni infection of dogs has a widespread geographic distribution throughout the country. A history of tick infestation was identified as a significant risk factor for B. gibsoni infection (p=0.0091), while sex (p=0.9411), age (p=0.0920) and breed (p=0.0549) of dogs were not statistically significant risk factors. These results indicate that tick infestation is the most dominant risk factor for B. gibsoni infection of non-fighting dogs in Japan and suggest that other B. gibsoni transmission routes, such as fighting and transplacental transmission, may be less important.  相似文献   
89.
A seroepidemiological survey of Neospora caninum infection among dogs in Japan was conducted using species-specific enzyme-linked immunosorbent assay with recombinant surface antigen (Nc-SAG1t). Among 1,206 dogs examined, 126 dogs (10.4%) from 30 prefectures from Hokkaido to Okinawa were positive to N. caninum infections, which were more frequently detected in females than males. Siberian Huskies showed the highest positive rate compared with the other breeds. Dogs with pyometra and diabetes mellitus showed the higher positive rates than dogs with other diseases or without diseases.  相似文献   
90.
This methodological review suggests what to do and what not to do in short‐chain fatty acid (SCFA) research for researchers, supervisors, scientific reviewers, and regulatory officers. High viscosity of gut contents, existence of bacterial biofilm and of mucus layer at the mucosal surface, and rapid absorption of SCFAs make it difficult to know their concentrations at the very surface of the mucosa. As lumen or fecal concentration of SCFAs does not reflect their rate of production, these parameters should not be used as measures of SCFA production or absorption. Effects of SCFAs can vary and even become opposite at different dose, time of/after exposure or time of the day. Thus, results without dose–response, time‐course, and diurnal variance experiments can be seriously misleading. It is also to note that too much emphasis on n‐butyrate should be avoided.  相似文献   
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