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221.
There has been a mass mortality of oak trees in the area along the coast of the Japan Sea. This phenomenon is caused by the ambrosia beetle Platypus quercivorus, which carries the ambrosia fungus Raffaelea quercivora. Extractives of a necrotic brownish coloration formed in the infected sapwood of Quercus crispula were investigated. The methanol extract of the damaged sapwood of Q. crispula was concentrated in vacuo and centrifuged to yield precipitates and the supernatant. The precipitates were subjected to Sephadex LH-20 column chromatography and preparative HPLC to describe a novel ellagic acid derivative (1). The 10 % methanol water-soluble part of the supernatant was subjected to medium-pressure ODS column chromatography and preparative HPLC, respectively, to analyze a known lignan (2). Sulfuric acid hydrolysis of (1) yielded an ellagic acid and a gallic acid. NMR and LC-TOF/MS indicated that an ellagic acid and a gallic acid bonded to a xylose with glycosidic and ester bonds, respectively. Compound (1) was identified as 4,5-dihydroxy-6-(3,7,8–trihydroxy-5,10-dihydro–chromeno[5,4,3-cde]chromen-2-yloxy)-tetrahydro-pyran-3-yl ester, and compound (2) was identified as (–)-lyoniresinol. The presence of (–)-lyoniresinol from damaged sapwood indicated that infection of R. quercivora may cause the formation of a pseudo-heartwood in the sapwood of Q. crispula. 相似文献
222.
Md Nazrul Islam Khandkar-Siddikur Rahman Md Mezbaul Bahar Md Ahsan Habib Keisuke Ando Nobuaki Hattori 《Urban Forestry & Urban Greening》2012,11(4):460-464
Greenbelts are effective tools for mitigation of traffic induced air and noise pollution. In this study, the potential role of greenbelts along the roadside for the reduction of air pollution and noise levels has been assessed by using seasonally monitored data in a megacity of Bangladesh. Correlation analysis was performed between the vegetation status, measured by canopy density and shelterbelt porosity, and the total suspended particles (TSP) removal percentage. Further, the reduction of noise level was also analyzed. The results showed that the greenbelts greatly contributed to reduce TSP pollution and it was as much as 65%. Noise level reduction was also achieved up to 17 dB when compared to the open area. Moreover, TSP removal percentage was correlated to the crown density. Area having higher crown density demonstrated less air pollution and lower level of noise compared to the area having lower crown density. Greenbelt showed better performance in summer time than winter. 相似文献
223.
Peripheral mononuclear cell response in Japanese black calves after oral administration of IFN-alpha
Ohtsuka H Tokita M Takahashi K Masui M Kohiruimaki M Hayashi T Ando T Watanabe D Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1063-1067
To investigate the effects of oral administration of an interferon (IFN)-alpha drug on the immune reaction of healthy Japanese Black (JB) calves, peripheral leukocyte populations and their ability to produce cytokine mRNA were analyzed after oral administration of IFN-alpha. Fourteen calves fed in one herd were divided into two groups; seven calves were orally administered 0.1 g/day of IFN-alpha from the day of birth to day 5 on each day (group 1, N=7), and the other seven calves were used as the control (group 2, N=7). Blood samples were collected from the jugular veins of all calves before administration and in weeks 1, 2, 4, 8, and 16 after birth. The number of MHC class II+CD14+ monocytes in the leukocytes population of group 1 increased gradually after birth, and significantly higher numbers were detected in week 4 compared with group 2. MHC class II-CD14+ monocytes in group 1 peaked in week 1, and a significant increase was detected compared with group 2. The level of IL-12 in the cytokine mRNA of group 1 increased gradually between weeks 1 and 2, and a significantly higher level of IL-12 was found compared with group 2. These results suggest that oral administration of IFN-alpha induces activation of the monocyte functions in JB calves. 相似文献
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226.
1. Recently, 2 novel neuropeptides were discovered, both derived from the same precursor by proteolytic processing, which bind and activate 2 closely related orphan G protein-coupled receptors, Named orexin-A and -B (Sakurai et al., 1998). Both stimulate food intake when administered centrally to rats. 2. Our aim was to elucidate whether central injection of mammalian orexin-A or -B stimulates food intake in the chick. 3. Under conditions of free access to food, orexin-A did not alter the food intake of chicks, but cumulative food intake was significantly suppressed by orexin-B. 4. The orexin-B was then administered to chicks deprived of food for 3 h to confirm its suppressive effect. No significant effect of orexin-B on food intake was detected. 5. Central injection of orexin-B did not modify food intake when appetite was stimulated by fasting. 6. Neither of these orexins appears to stimulate feeding in chicks. 相似文献
227.
Roy Bimol Chandra Ando Masashi Nakatani Masahiro Okada Tokihiko Sawada Yoshifumi Itoh Tomohiro Tsukamasa Yasuyuki 《Fisheries Science》2012,78(2):471-483
Following the successful development of Pacific bluefin tuna (PBT) aquaculture, it is of considerable importance to determine
the muscle fiber types and their growth patterns for future development. Muscle fiber profiles of dorsal ordinary, lateral
ordinary (LO) and dark muscles and their growth patterns in PBT from 3.0 to 54.3 kg body weight were studied. Muscle fibers
were histochemically stained for NADH-diaphorase and myosin adenosine triphosphatase activity (mATPase), and immunohistochemically
stained with S-58 slow-muscle myosin antibody. All muscle fibers in dorsal and LO muscles showed low NADH-diaphorase activity,
and acid-labile (pH 4.0 or 4.3) and alkali-stable mATPase activity. In LO muscle adjacent to dark muscle, three intensities
of mATPase activity were observed after acid pre-incubation at pH 4.5 or 5.0, and the activity was related to the muscle fiber
diameter. In dark muscle, all small and some large fibers stained intensely for NADH-diaphorase activity, related to their
high aerobic metabolism. The high-active fibers with NADH-diaphorase in dark muscle were positive for S-58 antibody. Some
large fibers in dark muscle showed intermediate NADH-diaphorase activity and high mATPase activity after alkali pre-incubations.
These are fast-twitch oxido-glycolytic fibers in dark muscle and transformed to red muscle fibers with increasing body weight. 相似文献
228.
Bimol C. Roy Y. Miyake M. Ando K.-I. Kawasaki Y. Tsukamasa 《Journal Of Aquatic Food Product Technology》2013,22(3-4):284-297
This study was carried out to determine the differences in proximate and fatty acid (FA) compositions in different flesh cuts of the most valuable cephalic portion of cultured (full-cycle), cultured fasted (full-cycle), and wild Pacific bluefin tuna (PBT; Thunnus orientalis). Cultured fasted PBTs were fasted for 6 days to ensure empty stomachs during harvesting and to determine the influence of fasting on the lipid and FA composition in different flesh cuts. Significantly higher lipid contents were observed (p < 0.05) in the dorsal akami (lean part) and the ventral o-toro (very fatty part) flesh cuts in cultured and cultured fasted PBTs than in wild ones. However, monounsaturated fatty acid (MUFA) contents in all flesh cuts were significantly higher in cultured and cultured fasted PBTs than in wild PBT. Wild PBTs contained significantly higher (p < 0.05) polyunsaturated fatty acid (PUFA) contents than other cultured PBTs in all flesh cuts except for the dorsal akami and wakaremi (fatty part near dorsal fin) flesh parts, and contained higher n-3 FA content than other PBTs—especially docosahexaenoic acid (DHA, C22:6n-3)—in the lipid fraction from the dorsal chu-toro (medium fatty part), ventral akami, ventral chu-toro, o-toro, and in dark flesh cuts. The flesh quality of cultured or cultured fasted PBTs has the advantage of having a higher total amount of essential FAs than that of wild PBT. 相似文献
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230.
Coniferous woods were modeled as honeycomb cellular solids consisting of hexagonal-prism tracheids to examine the mechanism for radial compression. Because of the abrupt breaks of radial cell walls, it was assumed that the flrst break followed Euler's equation of buckling. The nominal stress at the buckling of the radial cell wall was theoretically obtained based on this assumption, and the actual nominal stress was obtained experimentally. The theoretical stress was found to correspond almost to the experimental value. This finding suggests that the abrupt first break that occurs in wood under radial compression can be mainly attributed to the buckling of radial cell walls.Part of this work was presented at the 47th annual meeting of the Japan Wood Research Society, Kochi, April 1997 and at the 1997 meeting of the Research Society of Rheology in the Japan Wood Research Society, Tsukuba, December 1997 相似文献