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201.
Particleboards with thickness of 10 mm and densities of 0.6, 0.7 and 0.8 g/cm3 were manufactured from high-moisture particles using urea–formaldehyde resin and the effectiveness of air injection was examined. The temperature in the 0.6 and 0.7 g/cm3 boards was lower with air injection than without during the initial to middle stages of pressing, while the temperature in the 0.8 g/cm3 board remained lower with air injection than without throughout the entire pressing process. Air injection reduced the pressing time required to manufacture the 0.6 and 0.7 g/cm3 boards and also increased the internal bond strength of boards of all densities. In the 0.6 and 0.7 g/cm3 boards, air injection reduced the modulus of rupture (MOR), while in the 0.8 g/cm3 boards, the MOR was similar between those manufactured by injecting and not injecting air. Air injection was also found to be effective for boards of high densities. The effectiveness of the air injection on thick boards was investigated by manufacturing 20-mm-thick boards of 0.7 g/cm3. Without air injection, it was not possible to manufacture the 20-mm-thick boards, even by extended hot pressing, but air injection allowed the boards to be manufactured by pressing for 16 min. Air injection was also shown to be effective for manufacturing thick boards. 相似文献
202.
Particleboards of different densities (0.6, 0.7 and 0.8 g/cm3) and thicknesses (10 and 20 mm) were manufactured from low-moisture particles using an air-injection press. The effects of the air injection on preventing blowout of the boards of different densities and thicknesses were investigated by artificially creating blowout-prone conditions using metal frames. The effects of the air-injection pressure on the board performance were also investigated. 10-mm-thick boards of 0.8 g/cm3 pressed at 170 °C blew out when air was not injected, but were successfully manufactured by injecting air. 10-mm-thick boards at 150 °C showed constant internal bond (IB), regardless of density, but at 170 °C, IB was higher in boards of higher densities. This was likely due to accelerated hardening of the urea–formaldehyde resin at 170 than 150 °C. At both pressing temperatures, low air-injection pressure did not cause blowout and a reduction in board performance. Air injection also prevented the blowout of thick boards of 20 mm and enabled successful manufacture, showing its effectiveness. The IB of the 20-mm-thick board manufactured using the air-injection press exceeded that of 20-mm-thick board manufactured using an ordinary hot press. 相似文献
203.
Seiichiro Yonemura Masayuki Yokozawa Gen Sakurai Ayaka W. Kishimoto-Mo Nayeon Lee Shohei Murayama Kentaro Ishijima Yasuhito Shirato Hiroshi Koizumi 《Journal of Forest Research》2013,18(1):49-59
At the Takayama deciduous broadleaved forest Asiaflux site in Japan, the ecosystem carbon dynamics have been studied for more than two decades. In 2005, we installed non-dispersive infrared CO2 sensors in the soil below the site’s flux tower to systematically study vertical soil–air CO2 dynamics and explain the behavior of soil surface CO2 efflux. Soil–air CO2 concentrations measured from June 2005 through May 2006 showed sinusoidal variation, with maxima in July and minima in winter, similar to the soil CO2 effluxes measured simultaneously using open-flow chambers. Soil–air CO2 concentrations increased with soil depth from 5 to 50 cm: from 2,000 to 8,000 ppm in the summer and from 2,000 to 3,000 ppm in the winter under snow. Summer soil–air CO2 concentrations were positively correlated with soil moisture on daily and weekly scales, indicating that the Oi, Oe, and A horizons, where decomposition is accelerated by high-moisture conditions, contributed substantially to CO2 emissions. This result is consistent with the short residence time (about 2 h) of CO2 in the soil and larger emissions in shallow soil layers based on our diffusion model. We revealed for the first time that soil–air CO2 concentrations in winter were correlated with both snow depth and wind speed. CO2 transfer through the snow was hundreds of times the gas diffusion rates in the soil. Our estimate of the CO2 efflux during the snow-cover season was larger than previous estimates at TKY, and confirmed the important contribution of the snow-cover season to the site’s carbon dynamics. 相似文献
204.
205.
Hiroshi Ohta Kanae Takada Shidow Torisu Masashi Yuki Yu Tamura Nozomu Yokoyama Tatsuyuki Osuga Sue Yee Lim Masahiro Murakami Noboru Sasaki Kensuke Nakamura Masahiro Yamasaki Mitsuyoshi Takiguchi 《Veterinary immunology and immunopathology》2013
Inflammatory colorectal polyps (ICRPs) in miniature dachshunds are recently recognized as a major cause of large bowel diarrhea in this dog breed in Japan. ICRPs are characterized by the formation of multiple small polyps and a space-occupying large polyp in the colorectal area, and are thought to be a novel form of inflammatory bowel disease (IBD). In humans, specific cytokine patterns attributed to T helper (Th)1, Th17 and regulatory T cells have important roles in the pathogenesis of IBD. Thus, the aim of the present study was to assess the gene expression of cytokines of T cell subsets in the colorectal mucosa from dogs with ICRPs. Colorectal mucosal specimens from 10 dogs with ICRPs and 14 control dogs were used in this study. Interferon (IFN)-γ, interleukin (IL)-4, IL-17A and IL-10 mRNA expression was assessed using quantitative real-time PCR. IL-17A mRNA expression was significantly increased in large polyps compared to small polyps and controls. IFN-γ and IL-10 mRNA expression in large polyps were significantly higher than in controls. There was no significant difference in IL-4 mRNA expression among the three groups. IL-17A is thought to play important roles in the pathogenesis of ICRPs. IL-10 up-regulation could oppose the proinflammatory function of IL-17A. 相似文献
206.
207.
Itaru Yamaguchi Kensuke Myojo Hiroko Sanada Eri Sudo Sayaka Ootsuka Hiroshi Okumura Atsuko Takami Tomomi Yoneshige Yui Suzuki Minami Imaizumi Chie Takada Naoya Kimoto Koji Saeki Katsumi Takaba 《Journal of toxicologic pathology》2013,26(3):301-307
We histopathologically and immunohistochemically investigated a case of malignant
lymphoma that spontaneously developed in a male common marmoset at two years of age.
Beginning at two years four months of age, the animal had an enlargement of the
submandibular and inguinal lymph nodes, small subcutaneous nodules near the right breast
and an approximately fivefold increase in peripheral lymphocyte count compared with the
previous examination value. The postmortem findings at two years eight months of age
showed lymphadenopathy with enlargement of the thymus and spleen. Small- to
intermediate-sized neoplastic lymphocytes had diffusely proliferated in the enlarged
nodes. The neoplastic cells were pleomorphic and had irregularly shaped nuclei. The
nuclear chromatin staining revealed hyperchromatism in the small-sized cells, and the
intermediate-sized cells exhibited vesicular staining. An immunohistochemical examination
indicated that the neoplastic lymphocytes were positive for CD3 and negative for CD20,
thus suggesting that they had originated from T cells. In addition, the proliferation of
high endothelial venules and reactive epithelioid histiocytes was observed. Scattered
tingible body-laden macrophages were infrequently detected. Neoplastic lymphocytes were
also observed in the thymus, spleen, heart, lungs, liver, kidneys, adrenal glands and
femoral and sternal bone marrow. This malignant lymphoma in a young male common marmoset
was considered to fit the category of “peripheral T-cell lymphoma, not otherwise specified
(PTCL-NOS)” according to the new WHO system of classification. 相似文献
208.
Susan A. Elmore Mark Hoenerhoff Osamu Katsuta Hiroko Kokoshima Robert Maronpot Hiroaki Nagai Hiroshi Satoh Yasuhiro Tanaka Tomoaki Tochitani Seiichiro Tsuchiya Katsuhiko Yoshizawa 《Journal of toxicologic pathology》2013,26(2):231-257
The first joint Japanese Society of Toxicologic Pathology (JSTP) and National Toxicology
Program (NTP) Satellite Symposium, entitled “Pathology Potpourri,” was held on January
29th at Okura Frontier Hotel in Tsukuba, Ibaraki, Japan, in advance of the
JSTP’s 29th Annual Meeting. The goal of this Symposium was to present current
diagnostic pathology or nomenclature issues to the toxicologic pathology community. This
article presents summaries of the speakers’ presentations, including diagnostic or
nomenclature issues that were presented, select images that were used for audience voting
or discussion, and the voting results. Some lesions and topics covered during the
symposium include: treatment-related atypical hepatocellular foci of cellular alteration
in B6C3F1 mice; purulent ventriculoencephalitis in a young BALB/c mouse; a subcutaneous
malignant schwannoma in a RccHan:WIST rat; spontaneous nasal septum
hyalinosis/eosinophilic substance in B6C3F1 mice; a rare pancreatic ductal cell adenoma in
a young Lewis rat; eosinophilic crystalline pneumonia in a transgenic mouse model; hyaline
glomerulopathy in two female ddY mice; treatment-related intrahepatic erythrocytes in
B6C3F1 mice; treatment-related subendothelial hepatocytes in B6C3F1 mice; spontaneous
thyroid follicular cell vacuolar degeneration in a cynomolgus monkey; congenital hepatic
fibrosis in a 1-year-old cat; a spontaneous adenocarcinoma of the middle ear in a young
Crl:CD(SD) rat; and finally a series of cases illustrating some differences between
cholangiofibrosis and cholangiocarcinoma in Sprague Dawley and F344 rats. 相似文献
209.
Fujiko MINAMI-FUKUDA Makoto NAGAI Hikaru TAKAI Toshiaki MURAKAMI Tadashi OZAWA Shinobu TSUCHIAKA Sachiko OKAZAKI Yukie KATAYAMA Mami OBA Naomi NISHIURA Yukiko SASSA Tsutomu OMATSU Tetsuya FURUYA Satoshi KOYAMA Junsuke SHIRAI Hiroshi TSUNEMITSU Yoshiki FUJII Kazuhiko KATAYAMA Tetsuya MIZUTANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2013,75(12):1651-1655
210.
Onishi Junya Ikeura Hiroshi Paluashova Gaukhar K. Shirokova Yulia I. Kitamura Yoshinobu Fujimaki Haruyuki 《Paddy and Water Environment》2019,17(2):185-193
Paddy and Water Environment - In the arid lands covering Uzbekistan, furrow irrigation with low application efficiency is still widely used due to a lack of funds and shortage of labor. To save... 相似文献