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1.
Tsutsui T Shimizu T Hori T Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(12):1117-1121
Dogs, cats, and pigs have a bicornuate uterus, and transuterine migration of embryos occurs in 40% or more of pregnant animals. However, the mechanism of the transuterine migration has not been elucidated in dogs. Thus, we investigated the occurrence of transuterine migration of embryos when embryos were retained in an unilateral uterine tube with more ovulated ova (Experiment 1), when one ovary was excised (Experiment 2), and when ova ovulated from the right and left ovaries were fertilized with sperm from male dogs with different blood types (Experiment 3). Transuterine migration of embryos was observed in 7/8 (87.5%), 10/10 (100%), and 11/17 (67.4%) fertilized animals in Experiments 1, 2, and 3, respectively. In Experiment 3, intrauterine embryo mixing reported in pigs did not occur. These findings suggest that transuterine migration of embryos occurs due to the number of embryos that enter the uterus but that differences in the number of ovulated ova between the right and left ovaries or the number of embryos retained in the uterine tube do not affect the migration. 相似文献
2.
Dede Hermawan Toshimitsu Hata Kenji Umemura Shuichi Kawai Wakatsu Nagadomi Yasuo Kuroki 《Journal of Wood Science》2001,47(4):294-300
This study deals with the effects of curing treatment with gaseous and supercritical carbon dioxide on the properties of cement-bonded particleboard (CBP) manufactured by the conventional cold-pressing method. The hydration of cement and the mechanism of improvement were examined using X-ray diffractometry (XRD), thermal gravimetry (TG-DTG), and scanning electron microscopy (SEM) observations. The results are as follows: (1) The curing of cement was accelerated concomitantly with the improvement in mechanical and dimensional properties of CBP significantly by curing with gaseous or supercritical carbon dioxide. (2) Supercritical carbon dioxide curing imparted boards optimal properties at a faster rate than did gaseous curing. (3) Accelerated formation of calcium silicate hydrate and calcium carbonate and the interlocking of those hydration products on the wood surface are potentially the main reasons for the superior strength of carbon dioxide-cured boards. 相似文献
3.
Bambang Subyakto Toshimitsu Hata Isamu Ide Shuichi Kawai 《Journal of Wood Science》2001,47(3):199-207
Creep under fire of laminated veneer lumber (LVL) joined with metal connectors was studied. The fire-resistant performance of LVL butt joints connected with metal plates protected with graphite phenolic sphere (GPS) sheeting was discussed. The GPS sheeting was overlaid on the joint in different sizes and locations. The joint was exposed to a burner with a top flame temperature of 800°C and loaded with a load of 200 N to test for creep under fire. The results showed that the fire-resistant performance of the joint was markedly improved by the sheeting. The size and location of the GPS sheet significantly affected the time to rupture of the specimen, which was six times longer than that without GPS. Temperature measurements at the joint showed that the GPS sheeting distributed the heat along the surface and delayed failure. Thermographic images and analyses clarified the improvement in fire-resistant properties due to GPS. 相似文献
4.
Subyakto Toshimitsu?Hata Isamu?Ide Takeshi?Yamane Shuichi?KawaiEmail author 《Journal of Wood Science》2004,50(2):157-161
Laminated veneer lumber joints made with metal plate connectors were protected with wood carbon phenolic spheres (CPS) sheeting and tested for creep under fire. The effects of the carbonizing temperature of charcoal, used as raw material for the CPS sheets, the thickness, and the location of the sheet on the joint regarding the fire-resistance performance of the joint were studied. The time to rupture of the joints covered with CPS sheets made from charcoal carbonized at 800°C (CPS800) was slightly prolonged compared with that of uncovered joints. On the other hand, the time to rupture of CPS sheets made from charcoal carbonized at 1600°C (CPS1600) was markedly extended. The changes in the charcoal properties due to increasing the carbonizing temperature might be the main reason the CPS1600 sheets had higher fire-resistance performance. The thickness and location of CPS1600 sheets have significant effects on the fire resistance of the joint. A highly fire-resistant laminated veneer lumber joint was obtained using a CPS1600 sheet. The CPS1600 sheet with a thickness of 3mm covering three sides of the joint prolonged the time to rupture 16-fold compared with that of unprotected joints.Part of this paper was presented at the 4th International Wood Science Symposium, Serpong, Indonesia, September 2002 相似文献
5.
Kamiyama Matthew T. Matsuura Kenji Hata Toshimitsu Yoshimura Tsuyoshi Yang Chin-Cheng Scotty 《Journal of pest science》2022,95(3):1067-1079
Journal of Pest Science - The invasive, Halyomorpha halys (Hemiptera: Pentatomidae), is a severe economic insect pest native to East Asia. A strong effort has been made to identify natural egg... 相似文献
6.
Masafumi Katayama Tomokazu Fukuda Toshimitsu Hatabu Kiyoaki Narabara Asaki Abe Yasuhiro Kondo 《Animal Science Journal》2014,85(3):277-285
In chickens, although estrogen receptors (ER) are reported to be associated with the immunological processes, detailed information about the differences in ER expression in the tissues related to the development of lymphocytes is not fully known, especially during the developmental stage. To learn more about this immunological relationship, we used semi‐quantitative polymerase chain reaction method to detect the ER expression levels in the thymus tissues of chicks during the developmental stage. Furthermore, ER‐expressing cells were detected by immunohistochemistry. The results of this study show that the expression level of ER increased on embryonic day 16 and decreased on day 20. Furthermore, ER expression was significantly higher in male than in female chickens at day 16. The increased expression on day 16 and decreased level on day 20 were also reproduced in the incidence of immunoreactive cells, although there was a 1‐day delay in the elevated incidence of the cells. This study revealed the changes in ER expression and the incidence of ER‐positive cells in the thymus of chickens during the developmental stage. 相似文献
7.
Toshimitsu Onduka Daisuke Ojima Mana Ito Katsutoshi Ito Kazuhiko Mochida Kazunori Fujii 《Fisheries Science》2013,79(6):999-1006
We evaluated the acute toxicity of the antifouling biocide Sea-Nine 211 to the algae Chaetoceros calcitrans, Dunaliella tertiolecta, Tetraselmis tetrathele, and Skeletonema costatum, the crustacea Tigriopus japonicus and Portunus trituberculatus, and the polychaete Perinereis nuntia. The algae, and especially the diatoms C. calcitrans and S. costatum, were sensitive to Sea-Nine 211 toxicity, with the average acute toxicity values being 0.32, 3.9, 1.6, 0.22, 1.6, 12, and 27 μg/l for C. calcitrans, D. tertiolecta, T. tetrathele, S. costatum, T. japonicus, P. trituberculatus, and P. nuntia, respectively. A sediment toxicity test for Sea-Nine 211 using the polychaete P. nuntia revealed demonstrated that the 14-day median lethal concentration was 110 μg/kg dry-wt sediment and that growth was the most sensitive indicator. The chronic toxicity values of Sea-Nine 211 for the diatoms C. calcitrans and S. costatum were within the range of reported Sea-Nine 211 concentrations in seawater in coastal Japan, and the toxicity values for P. nuntia were within the reported concentrations in sediment. Based on these results, Sea-Nine 211 may have toxic effects on some sensitive species residing in the coastal areas of Japan, but the ecological risk posed by Sea-Nine 211 would appear to be confined to a limited area of Japanese coastal waters. 相似文献
8.
Onion-like graphitic particles observed in wood charcoal 总被引：1，自引：0，他引：1
9.
Dede Hermawan Toshimitsu Hata Shuichi Kawai Wakatsu Nagadomi Yasuo Kuroki 《Journal of Wood Science》2002,48(3):179-184
This study deals with the effects of carbon dioxide (CO2)-air concentration in the rapid curing method on the properties of cement-bonded particleboard manufactured using conventional cold pressing as the setting method. The hydration of cement was examined using X-ray diffractometry, thermal gravimetry, and scanning electron microscopy. The results are as follows: (1) The properties of CO2-cured boards improved with increasing CO2 concentration. When 10% or 20% CO2 was applied for 10 min of curing time, the properties of the CO2-cured boards were comparable to those obtained by conventional 2-week curing. (2) The hydration process of cement could be accelerated within several minutes using CO2 curing, even with a low concentration of 10%–20% CO2; a reduction in calcium hydroxide was observed followed by rapid formation of calcium carbonate. 相似文献
10.
Kengo Ishimaru Toshimitsu Hata Paul Bronsveld Takashi Nishizawa Yuji Imamura 《Journal of Wood Science》2007,53(5):442-448
Japanese cedar (Cryptomeria japonica) preheated at 700°C was subsequently heated to 1800°C and characterized by electron microscopy, X-ray diffraction, and micro-Raman
spectroscopy. The degree of disorder of carbon crystallites and the amount of amorphous phase decreased considerably with
an increase in heat treatment temperature to 1400°C, while carbon crystallites clearly developed above this temperature, showing
that the microstructure of carbonized wood undergoes drastic changes around 1400°C. Besides showing the bands for sp2-bonded carbon, the Raman spectra showed a shoulder near 1100 cm−1 assigned to sp3-bonded carbon. With an increase of heat treatment temperature, the peak position of the Raman sp3 band shifted to a lower frequency from 1190 to 1120 cm−1, which is due to the transformation of sp3-bonded carbon from an amorphous phase to a nanocrystalline phase. These data showed that the microstructure of carbonized
wood from 700° to 1800°C consisted of the combination of sp2- and sp3-bonded carbon, which is probably due to the disordered microstructure of carbonized wood. It is suggested that the sp3-bonded carbon is transformed from an amorphous structure to a nanocrystalline structure with the growth of polyaromatic stacks
at temperatures above 1400°C. 相似文献