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231.
232.
Iris Brémaud Nadine Amusant Kazuya Minato Joseph Gril Bernard Thibaut 《Wood Science and Technology》2011,45(3):461-472
Extractives can affect the vibrational properties tanδ (damping coefficient) and E′/ρ (specific Young’s modulus), but this
is highly dependent on species, compounds, and cellular locations. This paper investigates such effects for African Padauk
(Pterocarpus soyauxii Taub.), a tropical hardwood with high extractives content and a preferred material for xylophones. Five groups of 26 heartwood
specimens with large, yet comparable, ranges in vibrational properties were extracted in different solvents. Changes in vibrational
properties were set against yields of extracts and evaluation of their cellular location. Methanol (ME) reached most of the
compounds (13%), located about half in lumen and half in cell-wall. Water solubility was extremely low. tanδ and E′/ρ were
very strongly related (R
2 ≥ 0.93), but native wood had abnormally low values of tanδ, while extraction shifted this relation towards higher tanδ values.
ME extracted heartwood became in agreement with the average of many species, and close to sapwood. Extractions increased tanδ
as much as 60%, irrespective of minute moisture changes or initial properties. Apparent E′/ρ was barely changed (+2% to −4%)
but, after correcting the mass contribution of extracts, it was in fact slightly reduced (down to −10% for high E′/ρ), and
increasingly so for specimens with low initial values of E′/ρ. 相似文献
233.
Futoshi Ishiguri Imam Wahyudi Masae Takeuchi Yuya Takashima Kazuya Iizuka Shinso Yokota Nobuo Yoshizawa 《Journal of Wood Science》2011,57(3):241-246
The relationships between growth characteristics and wood properties were investigated for a threatened species, Pericopsis mooniana, to promote the establishment of plantations of this species in the tropics. Growth characteristics (diameter and height)
and stress-wave velocity (SWV) of trees were measured for 22-year-old P. mooniana trees planted in Indonesia. The trees were categorized into three groups, fast-growing, middle-growing, and slow-growing
trees, to investigate the effect of growth rate on the wood properties. In addition, radial variation of anatomical characteristics
and wood properties were determined. No significant correlation was found between growth characteristics and SWV. The values
for the vessel diameter, cell wall thickness of wood fibers, wood fiber length, basic density, modulus of elasticity, and
modulus of rupture from wood at the bark side were higher than those at the pith side. On the other hand, vessel frequency
gradually decreased from pith to bark. These results suggested that low-quality wood, such as juvenile wood, existed near
the pith area. 相似文献
234.
Kazuya Nakamura Noriko Yamagishi Masamichi Isogai Sadao Komori Tsutae Ito Nobuyuki Yoshikawa 《Journal of General Plant Pathology》2011,77(1):48-53
To examine whether Apple latent spherical virus (ALSV) has spread among apple trees in an orchard, we surveyed 21 apple trees surrounding two ALSV-infected trees for virus
infection using a double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). None of the 21 trees were infected,
indicating that ALSV has not spread from the infected trees to the neighboring apple trees since it was first detected in
1984. We analyzed seed embryos and seedlings derived from infected trees and detected ALSV in 10 of 223 seed embryos (4.5%)
and 10 of 227 seedlings (4.4%). From these results, we conclude that ALSV is seed-transmitted at a rate of ca. 4.5% in apple.
We also analyzed seed embryos and seedlings from uninfected apple trees that were hand-pollinated with pollen from infected
trees. We detected ALSV in only 1 of 260 seed embryos and in none of the 227 apple seedlings. This result indicated that the
seed transmission rate via infected pollen is only 0–0.38%. In situ hybridization analysis of ALSV-infected apple flower buds
showed that ALSV was present inside almost all pollen grains and in all ovary and ovule tissues, including the embryo sac
and inner integument. 相似文献
235.
Flynn O Quigley F Costello E O'Grady D Gogarty A Mc Guirk J Takai S 《Veterinary microbiology》2001,78(3):221-228
Rhodococcus equi has a low pathogenicity in cattle, but it occasionally causes lymph node granulomas, which are detected at abattoir post mortem inspection, and must be distinguished from tuberculous granulomas. Lymph node lesions were detected in 6719 cattle, from a total of 3,263,622 cattle examined post mortem in abattoirs, in the Republic of Ireland, during 1997 and 1998. Histological examination was performed on all lesions, principally for the purpose of identifying animals with tuberculosis. A total of 1122 of the lesions were cultured on blood agar and on Stonebrinks and Lowenstein-Jensen medium containing pyruvate, because the histological findings were difficult to interpret or were suggestive of R. equi infection. R. equi was isolated from 264 lesions. Almost all of the R. equi granulomas were confined to a single lymph node, and were present predominantly in the retropharyngeal, bronchial and mediastinal lymph nodes. R. equi granulomas were present in a significantly higher proportion of the lesions detected in steers and heifers compared to cows. The prevalence in the total population of 3.3 million cattle examined post mortem was 0.008%. The 15-17kDa antigens, associated with virulence in this organism, and the 20kDa antigen, associated with intermediate virulence, were not detected in isolates from 146 cattle, analysed by immunoblot assays. A PCR assay to detect the plasmid gene encoding the 15-17kDa antigens was also negative for isolates from these 146 animals. Plasmids were not detected in 30 isolates which were examined. 相似文献
236.
In the subsurface horizons of some paddy fields at the Kojima polder, Okayama Prefecture, the authors noticed a peculiar Mn-mottling, which had not been found in the common paddy fields. Several paddy soils in varying stages of maturity were carefuIIy surveyed at the Kojima polder. The soils were tentatively named OK4, OK7, OKS, and OK9. The ages of the fields after reclamation were about 10, 100, 150, and 250 years, respectively. Undisturbed samples were collected from 3 soils (OK4, OK7, and OKS) for microscopic observation and chemical analysis. 相似文献
237.
Hidenori Wada Supamard Panichsakpatana Makoto Kimura Yasuo Takai 《Soil Science and Plant Nutrition》2013,59(3):357-365
The 4 long-term experimental plots (Umbric haplaquept) with different fertilizer treatment at Cent. Agric. Exp. Sta. in Konosu City, Saitama Prefecture, were used for the sites of investigation. The 4 plots were NF (applied with no fertilizer), IF (applied with inorganic fertilizers), GM (applied with green manure and CaCO2), and OM (applied with manure and inorganic fertilizers). Flooded water, floating weed, upper (0-2cm) and lower (2-10cm) parts of Apg horizon and rhizosphere were collected from each plot before flooding, during flooding, and after drainage. These samples were analyzed for N2-fixing activity by acetylene reduction method, pH, Eh, and contents of Fe2+, NH4 +, chlorophyll-type compounds, and water-soluble carbohydrates. The N2-fixing activity of all samples showed almost the same pattern of change with time: very low before flooding, rapidly increased after flooding, the maximum value at the maximum tillering stage of rice plant, declined afterwards and reached a very low value after drainage. Rough estimation of the “N2-fixing capacity” of each part of the paddy field revealed that the most important site of the N2 fixation was the reduced Apg horizon, that the importance of flooded water and/or the oxidized layer in the N2 fixation was rather low except in infertile soil, and that the role of rhizosphere in the N2 fixation could not be neglected also in Japan. Reduced condition and content of easily decomposable organic substances were judged to be main factors which control the N2-fixing activity in the flooded soil on the basis of correlations between the Nt-fixing activity and several analytical data of the paddy soils. 相似文献
238.
Kazuya Suzuki 《Soil Science and Plant Nutrition》2013,59(4):1003-1007
The influence of continuous application of compost and fertilizer on soil macroaggregation in a field subjected to long-term (ca. 20 years) double cropping (rice and barley) was investigated. Soil samples were collected from 4 different plots: a) No-NF, fertilizer containing P and K but no N; b) F, fertilizer containing N, P, and K; c) F+ LC, fertilizer plus low rate of compost; and d) F+ HC, fertilizer plus high rate of compost. The application of compost and fertilizer increased the degree of macroaggregation (>0.25 mm), the contents of organic C, total N, hydrolyzable carbohydrates, and dithionitecitrate-bicarbonate (DCB) soluble Al, and the hyphal length in the order of No-NF<F<F+LC<F+HC plots. The degree of macroaggregation showed high correlation coefficients (r ≥ 0.95) with the contents of organic and inorganic components or the hyphal length. Most of these properties were strongly intercorrelated among themselves. The results obtained in this study suggest that organic matter including polysaccharides, active Al, and hyphae play an important role together in soil macro aggregation in the field subjected to double cropping under study. 相似文献
239.
In the previous paper1), the authors proposed a method for determining methyl mercaptan formed in paddy soils. In this method, methyl mercaptan was expelled by nitrogen gas from Paddy soils, and was introduced into 4% mercuric CYanide solution after separation from hydrogen sulfide by hydrous calcium chloride and lead acetate (solid). The methyl mercaptan caught by mercuric cyanide solution was measured by colorimetric method using dimethyl-p-phenylenediamine and ferric chloride solutions. And then, the analysis of several field soils was conducted by using this method. 相似文献
240.
Yoshinobu Hiraoka Yoshitada Sasaki Toshiaki Takai Akihiro Kawakubo Syojiro Miyoshi Shigeru Nakajima 《Fisheries Science》2007,73(6):1383-1387
ABSTRACT: Free and total histidine contents in the muscle of various fishes and invertebrates caught in the Seto Inland Sea were estimated. These contents were higher in the muscles from skipjack, yellowfin tuna, yellowtail and mackerel than in those from lizard fish, sea bream and hairtail. Invertebrate muscles, except squid, contained low free and total histidine. Boiled and dried anchovy ( niboshi ) contained lower free histidine than that of dried anchovy (suboshi). To prepare free histidine-rich extracts, the waste residue of soup stock from smoke-dried and shaved skipjack ( katsuobushi ) was digested with proteases. The extract of the enzyme digest contained high free histidine and was used to fortify niboshi with free histidine. If taken, the fortified niboshi may suppress food intake, and prevent obesity. 相似文献