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11.
Keisuke Kojiro Yuzo Furuta Makoto Ohkoshi Yutaka Ishimaru Misao Yokoyama Junji Sugiyama Shuichi Kawai Takumi Mitsutani Hiromasa Ozaki Minoru Sakamoto Mineo Imamura 《Journal of Wood Science》2008,54(6):515-519
To investigate the changes in microstructures of wood with elapsed time in the environment, CO2 adsorption onto dry wood was measured at ice-water temperature (273 K) for samples aged from 0.1 years to over 1000 years.
The micropore size distribution was obtained using the Horvath-Kawazoe method. Micropores smaller than 0.6 nm in wood decreased
in number with elapsed time in the environment, and a negative correlation was found between cumulative pore volume for pores
smaller than 0.6 nm and elapsed time in the environment. Cumulative pore volume in the 1000-year sample was almost half of
that in the 0.1- year sample. Micropores smaller than 0.6 nm in wood with a few decades or more of elapsed time increased
in number after rewetting and drying. Consequently, microstructures of wood with longer time elapsed in the environment were
considered to be more stable, because of longer-term thermal motion and possibly more repeated moisture adsorption and desorption
and/or temperature variation in the environment. 相似文献
12.
Ishii K Ogiyama Y Chikashige Y Soejima S Masuda F Kakuma T Hiraoka Y Takahashi K 《Science (New York, N.Y.)》2008,321(5892):1088-1091
The centromere is essential for the inheritance of genetic information on eukaryotic chromosomes. Epigenetic regulation of centromere identity has been implicated in genome stability, karyotype evolution, and speciation. However, little is known regarding the manner in which centromere dysfunction affects the chromosomal architectures. Here we show that in the fission yeast Schizosaccharomyces pombe, the conditional deletion of the centromere produces survivors that carry either a neocentromere-acquired chromosome at the subtelomeric region or an acentric chromosome rescued by intertelomere fusion with either of the remaining chromosomes. The ratio of neocentromere formation to telomere fusion is considerably decreased by the inactivation of genes involved in RNA interference-dependent heterochromatin formation. By affecting the modes of chromosomal reorganization, the genomic distribution of heterochromatin may influence the fate of karyotype evolution. 相似文献
13.
Masaaki Sugiura Yoshihiro Horibe Hitoshi Kawada Masahiro Takagi 《Pest management science》2011,67(9):1115-1123
BACKGROUND: Although insecticidal aerosols have been widely accepted for household use, the discharged amount should be maintained at minimum levels because they contain volatile organic compounds. Hence, it would be valuable to develop a technique whereby insecticide droplets adhere efficiently to an insect's body. The present study was undertaken in order to clarify how differences in the mode of adhesion to the insect body influence the knockdown effect. RESULTS: When the discharged volume of droplets with different diameters was the same, the adhesion volume of larger droplets was twice that of smaller droplets, resulting in a higher insect knockdown. In contrast, when the adhesion volume of the two droplet types was the same, a greater number of smaller droplets than larger droplets adhered, and the smaller droplets caused higher insect knockdown. The knockdown effect of both droplet types was lowered when the mesothoracic spiracles of cockroaches were blocked; however, the effect of larger droplets was lowered to a lesser degree. CONCLUSION: The results suggest that, the probability of adhesion to the more susceptible regions of an insect's body, i.e., areas surrounding the mesothoracic spiracles, was improved when a greater number of smaller droplets were adhered, resulting in higher knockdown. Copyright © 2011 Society of Chemical Industry 相似文献
14.
Shojiro Ichimata Yukiko Hata Kojiro Hirota Naoki Nishida 《Journal of toxicologic pathology》2022,35(3):255
A 32-year-old woman attempted suicide by ingesting Gloriosa bulbs and died approximately 2 days later. Toxicological examination revealed a potentially fatal blood concentration of colchicine (0.096 mg/L). In addition to the increased mitotic figures in the gastrointestinal mucosa, a unique finding for acute colchicine intoxication, pathological examination showed microvesicular lipid droplets in the liver, kidney, heart, and conduction system. Furthermore, central chromatolysis of neurons was observed in the pontine nucleus, medial accessory olivary nucleus, nucleus of the solitary tract, and nucleus ambiguus. Grumose degeneration of the cerebellar dentate nucleus was also evident. These pathological findings may help identify colchicine intoxication, even in the absence of evidence suggesting ingestion during autopsy. Moreover, pathological changes in the heart and central nervous system may be associated with the development of serious complications of acute colchicine intoxication. 相似文献
15.
The influences of heating history, cooling method, and cooling set on microstructures and the mechanical properties of water-swollen
wood were studied by measuring viscoelastic properties and dimensional changes while elevating temperatures between 20°C and
90°C. Both the viscoelastic properties and dimensional changes of waterswollen wood in the first heating process were quite
different from those in the other heating processes. The results revealed that the molecular state of green wood around room
temperature was stabilized and could not return to this state if drying or heating was carried out. Cooling methods greatly
affected the viscoelastic properties, while they hardly affected dimensional changes when the temperature was elevated. Localized
stress in the microstructures of water-swollen wood produced by quenching affected the mechanical properties in the heating
process, while external stress less than the proportional limit caused by a cooling set had no effect. This revealed that
much greater localized stress linked to the instability of waterswollen wood than the external stress in relation to the cooling
set occurred.
Part of this report was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003 相似文献
16.
Keisuke Kojiro Tsunehisa Miki Hiroyuki Sugimoto Masamitsu Nakajima Kozo Kanayama 《Journal of Wood Science》2010,56(2):107-111
To investigate micropores and mesopores in the cell walls of dry wood, CO2 gas and N2 gas adsorption onto dry wood were measured at ice-water temperature (273 K) and liquid nitrogen temperature (77 K). CO2 gas adsorption isotherms obtained were used for determining micropore volumes smaller than 0.6 nm by the HK method (Horvath-Kawazoe
method), and N2 gas adsorption isotherms obtained were used for determining the mesopore volume between 2 nm and 50 nm by the Barrett-Joyner-Halenda
(BJH) method. Micropores and mesopores existed in cell walls of dry wood, and the cumulative pore volume was much larger for
micropores than for mesopores. Micropores in the cell wall of dry wood decreased with elevating heat treatment temperature,
and the decreased micropore was reproducible by wetting and drying. Mesopores did not decrease so much with elevating heat
treatment temperature. Micropore volumes for the softwood Hinoki and the hardwood Buna were compared. A larger amount of micropores
existed in hardwood Buna than in softwood Hinoki, and this relationship was considered to correspond to the difference in
thermal softening properties for lignin in water-swollen Hinoki and Buna. This result probably indicates that micropores in
the cell walls of dry wood relate to the structure of lignin. 相似文献
17.
Nakaoka H Gaillard C Fujinaka K Watanabe N Ito M Kawada K Ibi T Sasae Y Sasaki Y 《Journal of animal science》2009,87(1):62-71
Data from 3 prefectures and a nationwide farming corporation were used to assess the usefulness of the "link provider data" in providing indirect genetic links for the national genetic evaluation for carcass weight across weakly connected subpopulations of the Japanese Black cattle. The data from the farming corporation provided genetic links to those of all prefectures and was therefore used as the link provider data. Two national genetic evaluation strategies under an animal model were compared, based on the generalized coefficient of determination (CD) of contrasts between mean EBV of sires or maternal grandsires (MGS) from different prefectures: strategy PA-1 was a pooled analysis of the data sets of the 3 prefectures, and strategy PA-2 was a pooled analysis of the data sets of the 3 prefectures and the farming corporation. The CD of the contrasts were greater for PA-2 than for PA-1. Under PA-2, the CD of the contrasts between mean EBV of sires or MGS ranged from 0.67 to 0.78 or from 0.61 to 0.70, respectively. Pooling the data from the 3 prefectures and the farming corporation increased the degree of connectedness through the link provider data rather than the amount of information by adding more data, thus improving the accuracy of prediction. The differences between mean EBV of sires or MGS from different prefectures were smaller for PA-1 than for PA-2. This finding suggests that genetic differences in carcass weight among prefectures are present, but that they would be confused with the environmental differences under PA-1 because of the lack of genetic connectedness among the prefectures. On the other hand, the genetic differences among the prefectures would be predicted precisely under PA-2 because the genetic connectedness among the prefectures was improved by using the link provider data. The results demonstrate that the link provider data could be used to unify within-prefecture evaluation to form a Japanese national genetic evaluation across weakly connected subpopulations. 相似文献
18.
Fusarium head blight (FHB) is a destructive disease of barley. The genetics and expression of resistance to FHB in barley is complex, and various spike characters are thought to possibly influence resistance. Tests using spray-inoculation of Fusarium graminearum at anthesis in greenhouse environments showed that two-rowed and cleistogamous varieties from Japan belong to the highest resistance group, while six-rowed and chasmogamous varieties are mostly susceptible. In order to evaluate the effect of such spike characters, including row type and flowering type, on FHB resistance, near-isogenic lines (NILs) differing in these characters were tested for their resistance. Two testing methods were used: the pot-plant and cut-spike methods, in which spikes at anthesis were spray-inoculated in greenhouse environments. The chasmogamous NILs and some six-rowed NILs were significantly more diseased than cleistogamous and two-rowed parent lines, respectively, and the difference in FHB severity was greater and more stable between cleistogamous/chasmogamous NIL pairs than between two-/six-rowed pairs. Slight or no differences were observed in glaucous/non-glaucous, normal/dense spike, normal/uzu type and normal/deficiens NIL pairs. The results indicate that the contribution of cleistogamy and/or the genetic background toward FHB resistance is more than that of row type and the other tested spike characters. Further, it should be possible to develop six-rowed varieties with FHB resistance nearly as good as that of the two-rowed varieties. 相似文献
19.
Tsunehisa Miki Hiroyuki Sugimoto Keisuke Kojiro Yuzo Furuta Kozo Kanayama 《Journal of Wood Science》2012,58(5):391-398
Enthalpy relaxation of dry wood has been investigated by temperature-modulated differential scanning calorimetry. The reversing and non-reversing heat flow changes revealed that enthalpy relaxation occurred in dry wood, which did not exhibit any clear glass transitions. This enthalpy relaxation behavior seemed to differ significantly from those of previously reported isolated lignins, which implies that the microstructure of dry wood possesses a rigid amorphous state derived from interactions among wood components. The observed enthalpy relaxation is considered to be related to other components besides lignin, and the time-dependent physical properties due to unstable states or physical aging of wood originate not only from lignin but also from other components, such as cellulose and hemicellulose and the interactions between them. 相似文献
20.
Synthesis of isoacteoside, a dihydroxyphenylethyl glycoside 总被引:1,自引:0,他引:1
Toshinari Kawada Ryuji Asano Kozo Makino Tomoyasu Sakuno 《Journal of Wood Science》2002,48(6):512-515
The total chemical synthesis of isoacteoside (1), 2-(3,4-dihydroxyphenyl)ethyl 6-O-caffeoyl-3-O-(-l-rhamnopyranosyl)--d-glucopyranoside, is described. An acteoside acetate with benzyl groups at the catechols (3: 2-(3,4-dibenzyloxyphenyl)ethyl 2,6-di-O-acetyl-4-O-[3,4-bis(O-benzyl)caffeoyl]-3-O-(-l-rhamnopyranosyl)--d-glucopyranoside) was treated with a solution of methy-lamine in methanol (MeNH2 in MeOH) to perform both deacetylation and caffeoyl migration, affording an isoacteoside derivative with benzyl groups at the catechols4b: 2-(3,4-dibenzyloxyphenyl)ethyl 6-O-[3,4-bis(O-benzyl) caffeoyl] -3-O-(-l-rhamnopyranosyl)--d-glucopyranoside —in 34% yield. Debenzylation of4b was successfully accomplished by catalytic transfer hydrogenation using 1,4-cyclohexadiene to give the target compound isoacteoside (1) in 54% yield.1H and13C nuclear magnetic resonance spectral data of the synthesized isoacteoside (1) were identical with those of the natural isoacteoside isolated fromPaulownia tomentosa (Thumb.) Steud.Part of this research was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 相似文献