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241.
Yi Min?WeiEmail author Tomoyuki?Fujii Yasushi?Hiramatsu Atsushi?Miyatake Shuichiro?Yoshinaga Tsuyoshi?Fujii Bunichiro?Tomita 《Journal of Wood Science》2004,50(4):327-336
The hydration behavior and strength performance of cement mixed with exploded wood fiber strand (WFS) obtained by the water-vapor explosion process have been studied previously. In the current study, the microstructural characteristics of cement–exploded WFS interfacial zone were examined using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). The Ca/Si ratios at the interfacial zones and the elemental compositions of hydration products deposited in the tracheid lumen were investigated. In addition, the morphological differences and compositional variations of hydration products that developed on the wood surfaces were examined. The results revealed that the Ca/Si ratios at the interfacial zones were strongly influenced by the mixture compositions, and that the elemental compositions of the hydration products that filled the tracheid lumen were significantly different from those of the cement paste in the mixtures. Differences in morphology and composition of hydration products at the wood surfaces were also observed to correspond to the different mixture compositions. These characteristics are considered to be directly related to the bond property, and thus, to the mechanical performance of WCM.Part of this report was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003 相似文献
242.
We investigated the biomass, vertical distribution, and specific root length (SRL) of fine and small roots in a chronosequence
of Japanese cedar (Cryptomeria japonica D. Don) plantations in Nara Prefecture, central Japan. Roots were collected from soil blocks up to 50 cm in depth in five
plantations of differing age: 4, 15, 30, 41, and 88 years old. Fine-root biomass reached a maximum (639 g m−2) in the 15-year-old stand before canopy closure, decreased in the 30-year-old stand (422 g m−2), and thereafter was stable. Except in the 30-year-old stand, fine-root biomass increased in deeper soil layers as stand
age increased, and the depth at which the cumulative biomass of fine roots reached 90% exhibited a good allometric relationship
with mean stem diameter. Both root-length density (root length per unit soil volume) and SRL decreased with soil depth in
all stands, indicating that plants mainly acquire water and nutrients from shallow soils. The highest SRL was observed in
the 4-year-old stand, but the relationship between SRL and stand age was unclear in older stands. The SRL in surface soils
seemed to decrease with increases in root-length density, suggesting that branching of the fine-root system during development
is related to density-dependent processes rather than age. 相似文献
243.
Naoko Miki Keiji Sakamoto Takashi Nishimoto Ken Yoshikawa Yoshio Hada 《Journal of Forest Research》2001,6(3):181-186
We examined the relationship between the incidence of pine wilt disease and moisture conditions in the stand level ofPinus densiflora Sieb. et Zucc. forests in the warm-temperate zone of the western part of Japan. For this analysis, pine trees killed by pine
wilt disease were distinguished from the suppressed trees by their position in the layer of the pine forest stand. The drainage
area, which is small in the upper part and large in the lower part of the slope, was adopted for representing the moisture
conditions in the soil of the slope. The percentage of the pine trees killed by pine wilt disease increased as the size of
the drainage area increased. This result suggested that the incidence of pine wilt disease tended to be high in areas with
moist conditions. Pine trees attacked by the pinewood nematode die from extensive water deficit due to tracheid cavitations.
Pine wilt disease mainly emerges in the summer when the soil water conditions become especially severe, and the radical water
stress is thought to accelerate the disease. It was assumed that pine trees in the plots with the small drainage area resisted
the influence of the attack of the pinewood nematode because pine trees in the plots with the small drainage area encountered
long-term water stress and acquired drought tolerance. Pine trees in the plots with the large drainage area were presumed
to be well established in the moist conditions and not to have acquired drought tolerance. The drought tolerance of pine trees
was thought to be an important factor in resistance to pine wilt disease. 相似文献
244.
Masaharu Kubota Naoko Hagiwara Takashi Shirakawa 《Journal of General Plant Pathology》2011,77(2):112-115
We developed a method to detect Acidovorax avenae subsp. citrulli from cucurbit seeds that is more sensitive than conventional growing-out methods. Seeds were cultivated in test tubes for
2 weeks, and the bacteria grew semi-selectively on the seeds and seedlings. The plants were then vigorously shaken in water
to suspend bacterial cells, and the suspension was spread on a selective medium for identifying the bacterium by colony appearance.
The method is suitable for research purposes to evaluate the percentage of seeds infested with the bacteria, but not to detect
bacterial contamination in commercial lots with thousands of seeds. 相似文献
245.
Tsuyuki R Yoshinari T Sakamoto N Nagasawa H Sakuda S 《Journal of agricultural and food chemistry》2011,59(5):1760-1766
The effects of cobalt chloride on the production of trichothecene and ergosterol in Fusarium graminearum were examined. Incorporation experiments with (13)C-labeled acetate and leucine confirmed that both 3-acetyldeoxynivalenol and ergosterol were biosynthesized via a mevalonate pathway by the fungus, although hydroxymethyl-glutaryl CoA (HMG-CoA) from intact leucine was able to be partially used for ergosterol production. Addition of cobalt chloride at concentrations of 3-30 μM into liquid culture strongly enhanced 3-acetyldeoxynivalenol production by the fungus, whereas the amount of ergosterol and the mycelial weight of the fungus did not change. The mRNA levels of genes encoding trichothecene biosynthetic proteins (TRI4 and TRI6), ergosterol biosynthetic enzymes (ERG3 and ERG25), and enzymes involved in the mevalonate pathway (HMG-CoA synthase (HMGS) and HMG-CoA reductase (HMGR)) were all strongly up-regulated in the presence of cobalt chloride. Precocene II, a specific trichothecene production inhibitor, suppressed the effects of cobalt chloride on Tri4, Tri6, HMGS, and HMGR, but did not affect erg3 and erg25. These results indicate that cobalt chloride is useful for investigating regulatory mechanisms of trichothecene and ergosterol production in F. graminearum. 相似文献
246.
Terakawa J Wakitani S Sugiyama M Inoue N Ohmori Y Kiso Y Hosaka YZ Hondo E 《The Journal of reproduction and development》2011,57(6):700-707
Leukemia inhibitory factor (LIF) is essential for embryo implantation in mice and plays an important role in other mammals including humans. Intraperitoneal (i.p.) injections with anti-LIF antibody (7.5 μg/g body weight, 3 times) between D3 (D1 = day of vaginal plug detection) and D4 effectively blocked embryo implantation; complete inhibition was achieved in C57BL/6J mice, and implantation was dramatically reduced in ICR mice (reduced to 27%). Normal rabbit IgG used as the control did not disturb embryo implantation. Anti-LIF antibody was localized not only in the stroma, but also in the luminal epithelium and the glandular lumen after i.p. injections. Growth-arrested blastocysts were recovered from the uterus without any implantation sites in both strains. Blastocysts made contact with the LE on the antimesometrial side; however, uterine stromal cells did not undergo secondary decidual reaction, and the uterine lumen was open, even at D7. Several regions of decidualization in ICR mice treated with anti-LIF antibody were smaller than those of the control, and development of blastocysts was delayed. The expression of LIF-regulated genes, such as immune-responsive gene-1 and insulin-like growth factor binding protein-3, was significantly decreased in C57BL/6J mice treated with anti-LIF antibody compared with the control, but not in ICR mice. The present study demonstrated that simple ip injections of an antibody are sufficient to block one of the important factors involved in embryo implantation in mice, and this method should also be easily applicable to the investigation of other factors involved in implantation. 相似文献
247.
In the mammalian ovary, more than 99% of follicles degenerate without ovulation and few oocytes ovulate and succeed to the next generation. Granulosa cell apoptosis plays a critical role in this process, follicular atresia. However, the molecular mechanisms responsible for the regulation of granulosa cell apoptosis have not been clarified. Death ligand and receptor systems are major apoptosis-inducing factors. This review describes the granulosa cell apoptosis via death ligand and receptor systems during follicular atresia in the porcine ovary. 相似文献
248.
Nishino K Hattori N Sato S Arai Y Tanaka S Nagy A Shiota K 《The Journal of reproduction and development》2011,57(5):586-593
The Sry (sex determining region on Y chromosome) gene is a master gene for sex determination. We previously reported that the Sry gene has tissue-dependent and differentially methylated regions (T-DMRs) by analyzing the DNA methylation states at CpG sites in the promoter regions. In this study, we found unique non-CpG methylation at the internal cytosine in the 5'-CCTGG-3' pentanucleotide sequence in the Sry T-DMR. This non-CpG methylation was detected in four mouse strains (ICR, BALB/c, DBA2 and C3H), but not in two strains (C57BL/6 and 129S1), suggesting that the CCTGG methylation is tentative and unstable. Interestingly, this CCTGG methylation was associated with demethylation of the CpG sites in the Sry T-DMR in the developmental process. A methylation-mediated promoter assay showed that the CCTGG methylation promotes gene expression. Our finding shows that non-CpG methylation has unique characteristic and is still conserved in mammals. 相似文献
249.
Kobayashi S Murakami K Sasaki S Okubo H Hirota N Notsu A Fukui M Date C 《Public health nutrition》2011,14(7):1200-1211
250.
Rika FUKUMORI Akinori YOKOTANI Toshihisa SUGINO Fumiaki ITOH Shiro KUSHIBIKI Hiroyuki SHINGU Naoko MORIYA Yoshihisa HASEGAWA Masayasu KOJIMA Kenji KANGAWA Taketo OBITSU Kohzo TANIGUCHI 《Animal Science Journal》2011,82(2):267-273
To investigate the effects of amino acids on ghrelin‐induced growth hormone (GH), insulin and glucagon secretion in lactating dairy cattle, six Holstein cows were randomly assigned to two infusion treatments in a cross‐over design. Mixture solution of amino acids (AMI) or saline (CON) was continuously infused into the left side jugular vein via catheter for 4 h. At 2 h after the start of infusion, synthetic bovine ghrelin was single injected into the right side jugular vein through the catheter. Ghrelin injection immediately increased plasma GH, glucose and non‐esterified fatty acids (P < 0.05) with no difference between both treatments. Additionally, plasma insulin and glucagon concentrations were increased by ghrelin injection in both treatments. The peak value of plasma insulin concentration was greater in AMI compared with CON (P < 0.05). Plasma glucagon concentration showed no difference in the peak value reached at 5 min between both treatments, and then the plasma levels in AMI compared with CON showed sustained higher values (P < 0.05). After plasma glucose concentration reached the peak, the decline was greater in AMI compared with CON (P < 0.05). These results showed that the increased plasma amino acids may enhance ghrelin action which in turn enhances insulin and glucagon secretions in lactating cows. 相似文献