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31.
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
32.
High concentrations of NO2 may accumulate in the upper regions of the atmospheric inversion layers. In this study, the climatological and geographical characteristics of two cases where a high nighttime NO2 concentration appeared in the inversion layer were studied, one on a slope on the Seto Inland Seacoast and in the Saijo Basin. On the Seto Inland Seacoast, the inversion layer appeared at 160 m a.s.l. There were remarkable differences in the concentration of NO2 and saturation deficit across the boundary of the inversion layer. In Saijo Basin, the inversion layer covered almost the whole basin up to 500 m a.s.l. The cold air lake appearing below 290 m contained an especially high level of humidity and NO2 concentration. In conclusion, it appears that the inversion layer plays a significant role as a cover preventing atmospheric NO2 from diffusing outside the layer. In both cases, it seemed that the water vapor pressure almost reached saturation in the high NO2 concentration zone. 相似文献
33.
The cerebellar flocculus has been implicated in vestibulo-oculomotor control. One major central input to this structure originates from brainstem cells in the paramedian tract (PMT), whose function is unknown. Here it is reported that PMT cells in the pons carry vestibular and eye movement signals and their pharmacological inactivation produces a leaky integrator combined with vestibular imbalance. The results suggest that PMT cells provide the cerebellum with sensory and motor signals that are essential for velocity-to-position integration, a common premotor process that is required in all motor systems. 相似文献
34.
Soma A Onodera A Sugahara J Kanai A Yachie N Tomita M Kawamura F Sekine Y 《Science (New York, N.Y.)》2007,318(5849):450-453
A computational analysis of the nuclear genome of a red alga, Cyanidioschyzon merolae, identified 11 transfer RNA (tRNA) genes in which the 3' half of the tRNA lies upstream of the 5' half in the genome. We verified that these genes are expressed and produce mature tRNAs that are aminoacylated. Analysis of tRNA-processing intermediates for these genes indicates an unusual processing pathway in which the termini of the tRNA precursor are ligated, resulting in formation of a characteristic circular RNA intermediate that is then processed at the acceptor stem to generate the correct termini. 相似文献
35.
Yurimoto H Abe K Abe M Ebihara M Fujimura A Hashiguchi M Hashizume K Ireland TR Itoh S Katayama J Kato C Kawaguchi J Kawasaki N Kitajima F Kobayashi S Meike T Mukai T Nagao K Nakamura T Naraoka H Noguchi T Okazaki R Park C Sakamoto N Seto Y Takei M Tsuchiyama A Uesugi M Wakaki S Yada T Yamamoto K Yoshikawa M Zolensky ME 《Science (New York, N.Y.)》2011,333(6046):1116-1119
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid. 相似文献
36.
Ota T Itoh A Tachi H Kudoh K Watanabe T Yamamoto Y Tadokoro T Maekawa A 《Journal of agricultural and food chemistry》2005,53(15):6112-6116
Morphiceptin (Tyr-Pro-Phe-Pro-NH(2)), tetrapeptide, was synthesized using dipeptidyl aminopeptidase IV (DP IV, EC 3.4.14.5) derived from Aspergillus oryzae RIB 915 as a catalyst. Tyr-Pro-OEt was incubated with Phe-Pro-NH(2) in the presence of DP IV under various conditions of temperature, concentrations of ethylene glycol, pH, reaction time, and others. Morphiceptin was obtained at 40% yield under the optimal reaction conditions: substrate, 4 mM Tyr-Pro-OEt.HCl and 20 mM Phe-Pro-NH(2).HCl; enzyme, DP IV, 0.275 nkat; solvent, 60% ethylene glycol containing 20 mM phosphate buffer at pH 7.0; amine, 4.2 mM diisopropylamine at 4 degrees C for 24 h. Amino group protection was unnecessary for synthesis of morphiceptin by DP IV. 相似文献
37.
The mean and range of indium content in unpolluted soils (Humic Andosols, Eutric Fluvisols, and Mollic Gleysols) was found to be 0.037 (0.016–0.078) μg/g dry wt. In soils polluted by common heavy metals, elevated values of indium up to 1.92 μg/g dry wt were observed together with an increase of cadmium, zinc, and lead. In contrast to indium, gallium content in polluted soils was nearly the same as that in unpolluted soils throughout the profiles. The mean and range of gallium content in all unpolluted and polluted samples was 14.2 (12.8–16.3) μg/g dry wt. The indium and gallium contents in 4 Canadian reference soils were also analyzed. 相似文献
38.
The objectives of this study were to investigate: 1) the pharmacokinetics of dietary docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA) using 13 C-labeled fatty acids; 2) the interorgan transport of DHA in the red sea bream by monitoring the DHA level of several organs; and 3) the relationship between the plasma DHA level and optimum dietary DHA level in the plasma of the red sea bream Chrysophrys major . For this purpose, a mixture of 38.5% of [13 C]DHA, 8.5% of [13 C]DPA, and 4.2% of [13 C]palmitic acid were given to the red sea bream at dose level of 8.0, 16.0, and 47.9 mg/kg by a single oral administration. For [13 C]DHA, the maximum plasma concentration (tmax ) occurred at 2.00–3.00 h after the oral administration. The peak plasma concentration (Cmax ) and the area under the plasma concentration-time curve to 24 h (AUC0-24 for [13 C]DHA level linearly increased with respect to dosage. [13 C]DHA appeared in each organ (plasma, erythrocyte and the fat body of the orbit, liver, intestine, skin, brain, heart and muscle) at 0.5 h and was observed until 24 h. From the values determined for the pharmacokinetic parameters, the range of the effective plasma DHA level for normal growth of the red sea bream was suggested to be between 21.0 and 40.3 μg/mL. For [13 C]DPA, the AUC0-24 and Cmax values also linearly increased with the dosage, but tmax did not depend on it. 相似文献
39.
Kohno H Okamoto C Iida K Takeda T Kaneko E Kawashima C Miyamoto A Fukui Y 《The Journal of reproduction and development》2005,51(6):805-812
Two experiments were conducted to compare the effect of estrus induction by controlled internal drug release (CIDR) and intravaginal cream containing 500 mg progesterone (P cream) in ewes during the non-breeding season. In the first experiment, twenty-four ewes were randomly grouped for two treatments with the different intravaginal devices for 12 days: Group A was the CIDR group and Group B was the P cream group. Blood was collected from all treated ewes, and progesterone (P(4)), estradiol 17-beta (E(2)) and luteinizing hormone (LH) concentrations were measured by enzyme immunoassay. In the second experiment, the conception rates from natural mating, estrus-detected AI (inseminated 12 h after estrus detection), or fixed-time AI (inseminated 42 h after removal of an intravaginal device) in 127 ewes treated with CIDR or P cream were compared. In Experiment 1, the rate of estrus induction and the time of estrus onset after device removal were 91.7% and 36.3 +/- 15.7 h in Group A, and 100% and 35.0 +/- 12.6 h in Group B, respectively. There were no significant differences between the devices. The mean plasma P(4) concentration in Group B was significantly (P < 0.01) lower than Group A between day -9 and day -1 (Day 0: the day of device removal). However, no significant differences were found in the mean E(2) concentrations of the two groups after treatment. The mean time of estrus onset in ewes with an observed LH surge and the time of LH surge after treatment were 23.3 +/- 8.7 h and 30.3 +/- 5.0 h for Group A and 27.6 +/- 6.5 and 26.3 +/- 8.0 h for Group B, respectively, and there were no significant differences. However, a significant difference (P < 0.05) was found in the mean time from the time of estrus onset to LH surge between Group A (6.4 +/- 6.7 h) and Group B (-1.3 +/- 4.1 h). In Experiment 2, the conception rates for natural mating, estrus-detected AI, and fixed-time AI were 55.0, 29.4, and 25.0% for Group A and 40.7, 25.0, and 42.1% for Group B, respectively, and there were no significant differences. These results suggest that the effect of induction of estrus and ovulation and the rate of conception after treatment were comparable to CIDR even though the plasma P(4) concentration of the P cream method tended to be low during the insertion period. 相似文献
40.
Nozaki H Wijayagunawardane MP Kodituwakku SP Yoshida T Nakamura T Arai I Urashima T Miyamoto A 《The Journal of reproduction and development》2005,51(2):229-234
N-acetylglucosaminyltransferase I (GnT I; EC 2.4.1.101), which catalyzes the first step in the conversion of oligomannose to complex or hybrid N-glycans of glycoproteins, was found in media cultured with bovine oviduct epithelial cells (BOEC) obtained from non-pregnant cows during the follicular phase. Combined treatment with specific hormones increased GnT I release from BOEC. Luteinizing hormone (LH; 10 ng/ml) alone slightly, but together with 17beta-estradiol (E2; 1 ng/ml), synergistically increased GnT I activity. Vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF) alpha, which have been shown to have their highest activities in the bovine oviduct during the periovulatory period, also increased in GnT I activity. This study provides the first evidence of an increase of GnT I release from BOEC in vitro, and shows that endocrine as well as local factors such as LH, VEGF and TNFalpha increase this activity. The results suggest that GnT I activity in the bovine oviduct may contribute to the induction of glycosylation and thereby contributing to the provision of the optimal microenvironment for fertilization and early development of the embryos. 相似文献