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21.
Shigeru Yamauchi Yoichi Sakai Yasuo Watanabe Michael Kenya Kubo Hideaki Matsue 《Journal of Wood Science》2007,53(4):324-331
The distributions of boron in Japanese cedar (Cryptomeria japonica D. Don) sapwood blocks treated with aqueous or methanolic boric acid [B(OH)3] solutions were explored through Raman spectroscopy and prompt gamma-ray analysis (PGA). B(OH)3 was the sole boron species observed in Raman spectra of the wood blocks treated with either solution. Plots of weight gain
of the treated wood blocks versus boron concentration in treatment solutions were found to be linear. The results indicated
that the methanolic solution makes it possible to impregnate wood with much larger amounts of boron than the aqueous solution.
PGA confirmed that B(OH)3 was highly enriched near the end grains of the treated wood blocks. Raman measurements suggested that boron content in the
bulk of the wood block is not as large as expected from the weight gain of the treated wood blocks when an ordinary air-drying
method is used. It was concluded that the aqueous solution impregnates the cell walls of wood with boron more easily than
the methanolic solution.
Part of this report was presented at the 55th (Kyoto, March 2005) and 56th (Akita, August 2006) Annual Meetings of the Japan
Wood Research Society. This article follows the previous rapid communication “Analysis of boron in wood treated with boric
acid solutions using Doppler broadening method of prompt gamma-rays.” J Wood Sci (2006) 52:279–281 相似文献
22.
Wen-Hsin Chung Hideo Ishii Kumiko Nishimura Michiyo Ohshima Toshitaka Iwama Hideaki Yoshimatsu 《Journal of General Plant Pathology》2008,74(5):364-374
Identifying the Fusarium species cause Fusarium head blight (FHB) and produces mycotoxins in wheat and other cereal is difficult and time consuming because of confusing
phenotypic classification systems. In Japan, the F. graminearum complex, F. culmorum, F. avenaceum, and Microdochium nivale predominantly cause FHB. The internal transcribed spacer (ITS) and 5.8S of rDNA, a partial sequence of β-tubulin and mitochondrial
cytochrome b (cytb) genes of the four species were PCR-amplified and analyzed. On the basis of the ITS, β-tubulin and cytb sequences, F. avenaceum and M. nivale are distinct from the F. graminearum complex and F. culmorum, whereas the F. graminearum complex is closely related to F. culmorum. Moreover, thiophanate–methyl-resistant isolates of the F. graminearum complex and F. culmorum did not have an amino acid substitution at amino acid codon 198 or 200 of β-tubulin. In contrast, very highly or highly thiophanate–methyl-resistant
isolates of M. nivale had Glu (GAG) substituted with Ala (GCG) or Lys (AAG) at codon 198, respectively. The allele-specific PCR assay was used
to identify the F. graminearum complex and F. culmorum, and these Fusarium species could be distinguished rapidly. 相似文献
23.
ABSTRACT: This study explored the fundamental process that controls interannual change in plankton biomass on the Pacific coast of Japan, focusing on the spring period of shirasu fishery. A 1-D model of primary production revealed that the strength of horizontal advection induced by warm water intrusion from the Kuroshio into the Pacific coast is the most critical for plankton biomass compared with other factors such as diffusion and production. This conclusion was also confirmed by a sensitivity analysis of the model. 相似文献
24.
To improve the properties of particleboard, boards were produced using a sealed press. With the sealed press, boards were
processed under high-temperature and high-pressure steam. This increased the saturation temperature, causing a dramatic rise
in temperature inside the board, faster curing of the binder, and a shorter pressing time. The boards were bonded with urea
formaldehyde resin, melamine urea formaldehyde resin, or poly(methylene diphenyl diisocyanate) (PMDI). The sealed press improved
the internal bond strength and thickness swelling of boards regardless of the binder used during the reduced pressing time.
The increased bonding strength improved the board properties, allowing PMDI with a lower resin content to be used for bonding
the boards. 相似文献
25.
Nobuhito Ohte Myron J. Mitchell Hideaki Shibata Naoko Tokuchi Hiroto Toda Goro Iwatsubo 《Water, air, and soil pollution》2001,130(1-4):649-654
To analyze the differences in the status and processes of nitrogen saturation in Japan and northeastern United States, we examined the hydrobiogeochemistry of nitrogen of forested watersheds in these regions. Two distinct differences were found between watersheds in Japan compared with those in US. 1) In Japanese watersheds, marked decreases of NO3 ? concentration in surface waters during the summer growing season were not found and NO3 ? concentrations sometimes increased especially in the summer at nitrogen saturated sites. This contrast with watersheds in US where decreases in NO3 ? concentration during the summer are commonly observed except those watersheds in advanced stages of nitrogen saturation. These differences in NO3 ? concentration relationships can be attributed to climatic differences, with Japan having high precipitation and high discharge during the summer, while in many regions of North America lowest discharges are found in the summer. The climatic regime in Japan leads to high rates of mineralization and the rapid transport of NO3 ? to streams in summer. 2) Japanese watersheds, even those with high NO3 ? concentrations in surface waters, show little evidence of acidification. This is in contrast to sites in US where increased NO3 ? concentrations, especially during episodic events, result in surface water acidification. 相似文献
26.
The observation of the regulation of fast protein dynamics in a cellular context requires the development of reliable technologies. Here, a signal regulation cascade reliant on the stimulus-dependent acceleration of the bidirectional flow of mitogen-activated protein kinase (extracellular signal-regulated kinase) across the nuclear envelope was visualized by reversible protein highlighting. Light-induced conversion between the bright and dark states of a monomeric fluorescent protein engineered from a novel coral protein was employed. Because of its photochromic properties, the protein could be highlighted, erased, and highlighted again in a nondestructive manner, allowing direct observation of regulated fast nucleocytoplasmic shuttling of key signaling molecules. 相似文献
27.
Hideaki Matsumoto 《Soil Science and Plant Nutrition》2005,51(5):613-615
Aluminum (Al) is a major element in the soil; 30–40% of arable land is acidic. Solubilized Al ion in acid soils inhibits root elongation. Intensive research on the Al tolerance mechanism has been conducted in the past few decades. Mechanism of Al tolerance can be classified into Al exclusion mechanism and intracellular tolerance mechanism. Efflux of organic acids from roots upon receiving the Al signal is the major Al exclusion mechanism. Efflux of organic acids through the channel in the plasma membrane was confirmed, and the gene specifically encoding malate transporter in Al-tolerant wheat was discovered recently. The regulatory mechanism in the efflux of organic acids upon protein phosphorylation may be operative. The production of reactive oxygen species (ROS) and their scavenging system are thought to be important in the intracellular tolerance mechanism. 相似文献
28.
Iwamori T Oosawa M Nukumi N Kano K Sudo K Naito K Tojo H 《The Journal of reproduction and development》2005,51(5):579-592
It has been suggested that whey acidic protein (WAP) may function as a protease inhibitor. However, the actual function of WAP remains obscure. We investigated the histological development of the mammary glands of transgenic mice ubiquitously expressing WAP and CAG/WAP transgene. Ubiquitous expression of WAP induced aberrant development of the lobular alveoli of the mammary glands: mammary alveoli that were either aberrantly large or small in size increased in number in the developing mammary glands of these transgenic females during pregnancy and lactation. The expression of beta-casein was precociously induced in the mammary glands of the transgenic females during early pregnancy and accompanying this was a histological observation that abnormally developed lobular alveoli filled with milk proteins appeared in the mammary glands of transgenic females during early pregnancy. However, during lactation, the development of mammary glands was impaired in transgenic females. To investigate the possible paracrine action of WAP associated with mammary gland aberration, we transplanted the mammary tissue of CAG/EGFP transgenic females into the fat pad of virgin CAG/WAP transgenic females and initiated pregnancy by mating. The development of mammary tissue transplanted to the recipient was histologically examined on day 3 of lactation. The results revealed that the development of grafted mammary tissues was impaired in a manner similar to that of the mammary glands of CAG/WAP transgenic females, indicating that the inhibitory effect of WAP acts via a paracrine mechanism. In vitro experiments using HC11 cells with forced expression of exogenous WAP demonstrated the inhibitory function of WAP on proliferation of mammary epithelial cells. 相似文献
29.
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
30.
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