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排序方式: 共有626条查询结果,搜索用时 15 毫秒
531.
Hakimullah HAKIM Chanathip THAMMAKARN Atsushi SUGURO Yuki ISHIDA Akinobu KAWAMURA Miho TAMURA Keisuke SATOH Misato TSUJIMURA Tomomi HASEGAWA Kazuaki TAKEHARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):211-215
Hypochlorous acid (HOCl) solutions were evaluated for their virucidal ability against a low pathogenic avian influenza virus (AIV), H7N1. HOCl solutions containing 50, 100 and 200 ppm chlorine (pH 6) or their sprayed solutions (harvested in dishes placed at 1 or 30 cm distance between the spray nozzle and dish) were mixed with the virus with or without organic materials (5% fetal bovine serum: FBS). Under plain diluent conditions (without FBS), harvested solutions of HOCl after spraying could decrease the AIV titer by more than 1,000 times, to an undetectable level (< 2.5 log10TCID50/ml) within 5 sec, with the exception of the 50 ppm solution harvested after spraying at the distance of 30 cm. Under the dirty conditions (in the presence of 5% FBS), they lost their virucidal activity. When HOCl solutions were sprayed directly on the virus on rayon sheets for 10 sec, the solutions of 100 and 200 ppm could inactivate AIV immediately after spraying,
while 50 ppm solution required at least 3 min of contact time. In the indirect spray form, after 10 sec of spraying, the lids of the dishes were opened to expose the virus on rayon sheets to HOCl. In this form, the 200 ppm solution inactivated AIV within 10 min of contact, while 50 and 100 ppm could not inactivate it. These data suggest that HOCl can be used in spray form to inactivate AIV at the farm level. 相似文献
532.
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
533.
The spatial distribution of stolons ofWisteria floribunda DC. was investigated, and the ecological significance of clonal growth of this temperate liana is discussed. The study plot
(0.15 ha) was located in a secondary deciduous broad-leaved forest dominated byQuercus serrata in central Japan. The tree canopy was almost closed with a mean openness of 4.2%.W. floribunda was dominant among lianas accounting for 86% of their total basal area.W. floribunda stolons of three individuals branched numerous times and intersected among individuals, and showed a large horizontal “web-like”
extension on the ground. The total length of stolons was 66.0, 260.2, and 310.6 m, respectively, for each individual. A mean
of 25 ramets were established on stolons per individual, and one-third of the ramets obtained a host tree. These results suggested
that the expansion of stolons was effective in obtaining host trees forW. floribunda individuals. On the other hand, clonal growth ofW. floribunda did not always contribute to vertical growth of ramets in the study forest, since few ramets reached the forest canopy. Lack
of sub-canopy trees in this forest appeared to constrain the vertical growth ofW. floribunda ramets, since sub-canopy trees are thought to bridge lianas from smaller trees to canopy trees. 相似文献
534.
Atsushi Mori Kazuhisa Tashiro Kyoko Makita Masahiro Takatani Tadashi Okamoto 《Journal of Wood Science》2005,51(1):38-41
In a series of studies, development of a new aqueous emulsion-type adhesive for use with wood or paper, which does not release formaldehyde or volatile organic solvents, was attempted. For the purpose of increasing both initial and final adhesive strengths, we selected a system consisting of acrylic monomers copolymerized with functional monomers such as diacetone acrylamide and some cross-linking agents such as dihydrazide or polymeric methylene diphenyl diisocyanate (pMDI). It was found that dihydrazide cross-linker was effective for both the initial and final adhesive strengths, suggesting contribution of hydrazone bonds to the bonding strengths. Cross-linking with pMDI might be slow and was not important in the initial bonding. However, its cross-linking effect might develop gradually, because the adhesive showed good final strengths using pMDI as a cross-linker. 相似文献
535.
Mariko?YoshiokaEmail author Atsushi?Miyata Tadashi?Yagi Yoshiyuki?Nishio 《Journal of Wood Science》2004,50(6):511-518
A ring-opening polymerization of cyclic esters -caprolactone (CL) and/or l-lactide (LACD) was carried out in the presence of methyl--d-glucoside (m-Glc) as an activated substrate and tin(II) 2-ethylhexanoate (SnEht2) as a catalyst. This led to successful synthesis of an armed polyester polyol with m-Glc as the core. These polyols were characterized through gel permeation chromatography, hydroxyl value assessment, differential scanning calorimetry, and viscosity measurements. It was clarified that the thermal properties and tractability of the synthesized polyols are closely related to the structural characteristics of the side chain polyesters, such as their length and chemical composition. Polyurethane foams were also prepared by mixing an appropriate amount of the polyols with diphenyl methane diisocyanate, a foaming agent (water), and other additives, and their mechanical properties were examined. Two polyurethane foams manufactured from polycaprolactone-polyols that were synthesized at a CL/m-Glc ratio of 2 or 5, were used in a biodegradation test in a closed system of activated sludge suspension. Evidence of their biodegradation is presented based on data showing oxygen consumption by the pulverized samples. 相似文献
536.
Atsushi Yoshimoto 《Journal of Forest Research》2001,6(2):101-110
The previous stochastic models applied for Gentan probability estimation utilized either a stationary or nonstationary Poisson
process to describe the forest owners’ harvesting behavior by means of the counting process. A nonstationary Poisson process
has the advantage over a stationary Poisson process of capturing a time-dependent change of harvesting events. However, a
nonstationary Poisson process can lack one preferred characteristic of the probability theory when utilizing an average growth
function with an asymptotic nature of growth. That is, the sum of the derived Gentan probabilities over time does not always
become unity. In this paper, we introduce a state-dependent discrete forest growth model with an asymptotic nature of growth
to overcome the problem, then propose a stochastic model applied for Gentan probability estimation. The Mitscherlich type
growth function is utilized. The derived probability law to capture the harvesting behavior is shown to be the binomial probability
law. The derived probabilities prove to sum up to unity over time. 相似文献
537.
To clarify the biosynthesis of syringyl lignans and lignan formation by stereoselective coupling of monolignols, formation of (+)-syringaresinol and (+)-pinoresinol inLiriodendron tulipifera were investigated by means of feeding experiments. Following individual administration ofl-[U-14C]phenylalanine and [8-14C]sinapyl alcohol to excised shoots ofL. tulipifera and their subsequent metabolism for 3h, free [14C] lignans and [14C] lignan glucosides were extracted from both of the stems and leaves with methanol and divided into an ether fraction and an aqueous one, respectively. The glucosides were hydrolyzed by a combination of cellulase and-glucosidase to liberate [14C]lignans as aglycones.l-[U-14C]Phenylalanine was incorporated into free (+)-[14C]syringaresinol and its glucosides; the (+)-[14C]syringaresinols in the stems and leaves had 52% enantiomeric excess (% e.e.) and 42% e.e., respectively; and the (+)-[14C]syringaresinol aglycones from the glucosides in the stems and leaves had 20% e.e. and 22% e.e., respectively. Furthermore, [8-14C]sinapyl alcohol was incorporated into (+)-[14C]syringaresinol and its glucosides in the stems. These results suggest that the (+)-enantiomer of syringaresinol was enantioselectively formed from two molecules of sinapyl alcohol inL. tulipifera followed by transformation into the (+)-syringaresinol glucosides, accompanying the formation of racemic syringaresinol by nonselective coupling and the subsequent transformation of the racemate into their glucosides.l-[U-14C]Phenylalanine was incorporated also into free (+)-[14C]pinoresinol and its glucosides with 12%–42% e.e.Part of this paper was presented at the 47th Annual Meeting of the Japan Wood Research Society, Kochi, April 1997 相似文献
538.
Diurnal changes in gas exchange and chlorophyll fluorescence were measured in the top canopy leaves of the tropical rainforest tree species, Macaranga conifera (Zoll.) Muell. Arg. during a drought year. Maximum values of net photosynthetic rate (P(n), 10 &mgr;mol m(-2) s(-1)) and stomatal conductance (g(s), 0.2 mol m(-2) s(-1)) were found in east-facing leaves in early morning. After 1000 h, both P(n) and g(s) decreased. Minimum daytime values of P(n), g(s), and photosystem II (PSII) quantum yield (DeltaF/F(m)') were found in horizontally fixed leaves. At a given electron transport rate through PSII (ETR), P(n) was higher in early morning than at midday, suggesting a high rate of photorespiration at midday. We tested the hypothesis that the effect of low leaf temperature (T(leaf)) on P(n) is significant in the early morning, whereas the effect of low g(s) on P(n) predominates at midday. In the early morning, when T(leaf) was increased from 32 to 38 degrees C by artificial heating, P(n) at a given ETR decreased 29%, suggesting that the low T(leaf) was associated with a high P(n). When T(leaf) at midday was decreased from 37 to 32 degrees C by artificial cooling, P(n) increased 22%, but P(n) at a given ETR was higher in early morning than at midday, even at the same low T(leaf) (32 degrees C). This suggests that the rate of photorespiration was higher at midday than in early morning because low g(s) at midday caused a reduction in leaf intercellular CO(2) concentration. We conclude that low P(n) at midday was the result of both a reduction in the photochemical process and an increase in stomatal limitation. 相似文献
539.
Hideki Takahashi Hiroyuki Sekiguchi Toyoaki Ito Masashi Sasahara Noriko Hatanaka Atsushi Ohba Shu Hase Sugihiro Ando Hiroshi Hasegawa Shigehito Takenaka 《Journal of General Plant Pathology》2011,77(2):121-131
Plants harbor microorganisms that are thought to stimulate plant defense systems or promote plant growth. Individual species
in these intercellular microbial communities are often not sufficiently abundant to be easily described, although some endophytic
microorganisms amenable to culture have been characterized. To better understand the microbial population of plants, we collected
intercellular fluid (IF) from leaf blades and sheaths of rice and subsequently isolated DNA from the IF. Denaturing gradient
gel electrophoresis (DGGE) analysis of 16S and 18S rDNA fragments amplified from IF DNA by PCR indicated that these band patterns
were distinguishable from those of a leaf surface-wash fluid (SF). Analysis of a set of rDNA fragments amplified from IF DNA
of rice with different genotypes, paddies or growth stages for the primary survey of overall microbial community in the IF
suggested that this approach is suitable for analyzing microbial diversity in the IF from various plant samples. Actually,
comparative analysis of amplified rDNA fragments of rice and other five plant species indicated that the microbial diversity
in IF is likely to vary substantially among plant species. We can also use sequence analysis of 16S rDNA fragments amplified
from rice IF DNA to identify species including unculturable bacteria and proteobacteria and Xanthomonas and 18S rDNA fragments to identify Tilletiaria anomala, Tilletia iowensis, Ustilago maydis and unculturable eukaryotes. Thus, IF DNA analysis seems to be a good tool to further study the microbial ecology of plants. 相似文献
540.
Saito T Honma D Tagashira M Kanda T Nesumi A Maeda-Yamamoto M 《Journal of agricultural and food chemistry》2011,59(9):4779-4782
New red leaf tea cultivar 'Sunrouge' (Camellia taliensis × Camellia sinensis), for which an application for registration was made in 2009, is an anthocyanin-rich tea. The anthocyanin content of 'Sunrouge' was the highest among 4 tea cultivars, and was 8.4 times higher than that of 'Yabukita'. We purified and isolated 6 anthocyanins from 'Sunrouge' by chromatography, and identified them by LC/MS/MS and NMR analysis. As a result, the four anthocyanins were identified as delphinidin-3-O-β-D-(6-(E)-p-coumaroyl)galactopyranoside (2), delphinidin-3-O-β-D-(6-(E)-p-coumaroyl)glucopyranoside (3), cyanidin-3-O-β-D-(6-(E)-p-coumaroyl)galactopyranoside (4), and cyanidin-3-O-β-D-(6-(E)-p-coumaroyl)glucopyranoside (5), and the other two were estimated as delphinidin-(Z)-p-coumaroylgalactopyranoside (1), petunidin-(E)-p-coumaroylgalactopyranoside (6). Compound 3 was found in tea for the first time. In general, anthocyanins have various bioactivities, including relieving eyestrain and antioxidative effects, so it is expected that drinking 'Sunrouge' tea brings in similar bioactivities. 相似文献