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1.
A new approach is proposed for the evaluation of the brittleness of heat-treated Styrax tonkinensis wood. Heat treatment made wood more brittle when wood was heated at a higher temperature or for a longer time. The brittleness increased to four times that of the control when wood was heated at 200°C for 12 h. For treatment at 160°C, the increase in brittleness without any change in weight is thought to be possibly caused by the relocation of lignin molecules. At higher temperatures, loss of amorphous polysaccharides due to degradation is thought to become the main factor affecting brittleness. The crystallites that were newly formed after 2 h of treatment showed brittleness that was different from that of the inherent crystallites remaining after 12 h of heat treatment. This inherent crystalline cellulose possibly plays a role in brittleness. There is also the possibility of using color to predict the brittleness of heat-treated wood.  相似文献   
2.
Fibrodysplasia ossificans progressiva (FOP)-like condition was diagnosed in a Japanese domestic cat with stiffness, marked atrophy of the muscles, and limited mobility of all joints in both the pelvic limbs. Etretinate, a retinoid, was used for medical management; however, no improvement in the clinical signs was observed. Inheritance of the disorder has not yet been demonstrated. Furthermore, the clinical signs and histopathological findings of feline FOP-like condition in the present case differed from those of the previously reported cases.  相似文献   
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Asian soybean rust (ASR) caused by Phakopsora pachyrhizi is one of the most serious soybean (Glycine max) diseases in tropical and subtropical areas. A soybean line, PI 587855, showed a resistance phenotype against ASR pathogens in Japan and South America at high frequency; however, little is known of the genetic control of this resistance and chromosomal location of the corresponding locus. Therefore, the aim of this study was to study the inheritance of PI 587855 resistance and map the corresponding locus with SSR markers aiming to use the linked markers in marker‐assisted selection. In the segregating population, resistance to ASR appeared to be controlled by a single dominant gene. The ASR resistance locus was mapped near to the chromosomal region where the resistant loci, Rpp1 and Rpp1‐b, were previously mapped. Comparative genetic mapping and disease reaction profiles of other seven lines carrying Rpp1 or Rpp1‐b to four Brazilian ASR isolates revealed that the resistance reaction exhibited by PI 587855 was similar to that of Rpp1‐b‐carrying varieties which have useful resistance to South American ASR strains.  相似文献   
5.
Water adsorption capacities were evaluated for moso bamboo samples that were heated at 200°C for various times and conditioned in a closed container at 97% relative humidity at 20°C. Logistic regression analysis was used for curve fitting to the adsorption data and its parameters were analyzed. These parameters were compared with those derived previously from the Dubinin and Radushkevich theory. The properties of the heat-treated samples changed after 5 h of heating. With less than 5 h of heating, hydroxyl groups provided the main adsorption sites but their numbers decreased on heating. After 5 h, gasifi cation of the bamboo increased and capillaries formed. Part of this article was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007  相似文献   
6.
Bamboo-derived activated carbon prepared by superheated steam (BAC) exhibited performance for utilization as an electric double layer capacitor (EDLC) electrode. Pore structure and EDLC performances were investigated by comparison with phenol resin-derived activated carbon (MSP-20), which is commercially available and often used for the purpose. The nitrogen adsorption isotherm showed that BAC had a large BET-specific surface area of 1268 g/m2 with a developed pore structure, especially of the mesopore, in comparison with MSP-20. It is considered that inherent ash in bamboo promoted activation, in addition to physical activation by superheated steam. Capacitance per electrode volume (CV) was 52 F/cm3 with BAC. Because the density of BAC is high (0.78 g/cm3) compared with that of MSP-20 (0.58 g/cm3), sufficient CV for usage was obtained, although the capacitance per electrode mass (CM) at 5 mA/cm2 itself of BAC (67 F/g) was lower than that of MSP-20 (126 F/g). With IR drop, the resistance value of BAC (9.7 Ω) was lower than that of MSP-20 (10.5 Ω). Especially, the diffusion resistance of BAC disclosed to be smaller than that of MSP-20. These results indicated that BAC produced by steam activation is a promising material with a pore structure suitable for ion transfer in EDLC.  相似文献   
7.
The antifungal activities of hyoscyamine and scopolamine, major alkaloids extracted from the desert plant Hyoscyamus muticus, against two rice pathogens, Magnaporthe oryzae and Rhizoctonia solani, were studied. The minimum inhibitory concentration of hyoscyamine that resulted in distinctive inhibition (MIC50) was 1 μg/ml for both fungi. Exposure to hyoscyamine caused the leakage of electrolytes from the mycelia of both fungi. Hyoscyamine (>1 μg/ml) irreversibly delayed or inhibited conidial germination and appressorium formation in M. oryzae grown on polystyrene plates. Hyoscyamine effectively inhibited the attachment of conidia to the surface of rice (Oryza sativa) leaves and inhibited appressorium formation on the leaves. A high concentration of scopolamine (1000 μg/ml) also delayed or inhibited conidial germination in M. oryzae, but conidial germination was restored after washing the conidia with water. Antifungal activity of hyoscyamine was reduced by scopolamine. Magnaporthe oryzae infection was significantly suppressed (by >95%) in leaves of intact rice plants treated with hyoscyamine (10 μg/ml). Moreover, 10 μg hyoscyamine/ml significantly reduced the disease severity index for sheath blight to ≤0.2, when compared with the disease index of control plants (>7.0). Hyoscyamine (>20 μg/ml) completely inhibited sclerotial germination and development of R. solani by delaying the initiation, maturation, and melanization of the sclerotia. These results suggest that tropane alkaloids may be useful for controlling blast and sheath blight diseases of rice and for studying the mechanisms that regulate conidial germination in M. oryzae and sclerotial germination and development in R. solani.  相似文献   
8.
A subchronic feeding study of l-serine (l-Ser) was conducted with groups of 10 male and 10 female Fischer 344 rats fed a powder diet containing 0, 0.06, 0.5, 1.5 or 5.0% concentrations of l-Ser for 90 days. There were no toxicologically significant, treatment-related changes with regards to body weight, food intake, water intake or urinalysis data. In several of the hematology, serum biochemistry and organ weight parameters, significant changes were observed between some of the treated groups and the controls. All these changes, however, were subtle and lacked any corresponding pathological findings. In addition, the increased or decreased values remained within the range of the historical control values. In fact, histopathological assessment revealed only sporadic and/or spontaneous lesions. In conclusion, the no-observed-adverse-effect-level (NOAEL) for l-Ser was, therefore, determined to be at least a dietary dose of 5.0% (2765.0 mg/kg body weight/day for males and 2905.1 mg/kg body weight/day for females) under the present experimental conditions.  相似文献   
9.
Journal of General Plant Pathology - Metyltetraprole is a novel quinone outside inhibitor (QoI) fungicide designed to avoid cross-resistance in cytochrome b G143A-harboring QoI-resistant...  相似文献   
10.
Of all plant materials used to cover the roofs of traditional Japanese buildings, Japanese cypress (Chamaecyparis obtusa) bark, hiwada, has the longest service life and has been used from ancient times. However, wood and bark properties after hiwada harvest have not been evaluated in detail. We studied whether decortication for hiwada production in winter affected xylem and phloem formation. Decorticated trees still preserved all inner bark and part of the outer bark, and both decorticated and control trees had similar annual ring structures at all stem heights in the xylem and phloem. In both xylem and inner bark, no significant difference in ring width at any stem height was found between annual rings before and after decortication. Thus, this study revealed that the decortication of bark for hiwada production does not affect the formation of xylem and the inner and outer bark if decortication is carried out by highly skilled workers in winter.  相似文献   
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