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61.
ABSTRACT: The nucleotide sequences of Japanese flounder Paralichthys olivaceus , major histocompatibility complex (MHC) cDNA, classical MHC class Iα, non-classical MHC class Iβ, MHC class IIα and IIβ, were determined. The domain structures and antigen binding motifs of vertebrate MHC are conserved in the Japanese flounder MHC. A phylogenetic analysis supports the classification of these genes into class I and class II MHC. Classical MHC class Iα was ubiquitously expressed, whereas the non-classical MHC class Iβ was expressed mainly in lymphoid organs, gills, intestine and stomach. The MHC classes IIα and IIβ were also ubiquitously expressed. 相似文献
62.
63.
The relationship between the moisture content (MC) of wood blocks and the feeding activities of two Japanese subterranean termites, Coptotermes formosanus Shiraki and Reticulitermes speratus (Kolbe), was investigated with two choice tests. When three wood blocks with low MC (6%–12%), middle MC (79%–103%), and high MC (140%–182%) were exposed to workers of C. formosanus and R. speratus in a choice test, the feeding preferences were found in the middle MC blocks for C. formosanus, and the middle and high MC blocks for R. speratus, although wood blocks of low MC were also attacked. In a second choice test, wood blocks consisting of five pieces with water-impregnated (MC: 133%–191%) top, middle, or bottom piece were exposed to workers of both species. Higher consumptions were generally obtained in water-impregnated wood pieces and bottom pieces. 相似文献
64.
Michito Tsuyama Hajime Kobayashi Masaru Shinya Hisashi Yahata Yoshichika Kobayashi 《Journal of Forest Research》1996,1(2):79-85
Using attached and detached leaves ofAcer palmatum Thunb. andRhaphiolepsis umbellata Makino, pulse-modulated chlorophyll fluorescence and CO2 exchange were measured. Quantum yield of photosynthesis was determined from the fluorescence parameter(Fm′−Fs)/Fm′, where (Fm′−Fs) was defined as the difference between steady state chlorophyll fluorescence (Fs) and maximum fluorescence (Fm′) elicited by a saturating light pulse. The rate of electron transport through photosystem II (total electron flow) was calculated
from the product of quantum yield andA (PFD), whereA is the rate of absorbed photons as given by leaf absorptance, and PFD is the photon flux density at the leaf surface. The
rate of electron transport dependant on CO2 uptake (assimilative electron flow) was calculated from the gross photosynthetic rate in a leaf. The difference between the
rates of total and assimilative electron transport was denoted as the rate of non-assimilative electron transport which depends
on photorespiration and oxygen reduction. Available data provided quantitative information on the rate of non-assimilative
electron flow in intact leaves. When leaf photosynthesis ofA. palmatum was measured under sunlight, the rates of total and assimilative electron transport were determined to be approximately 900
and 150 μmol equiv. e/mg Chl·h, respectively. The difference (750 μmol equiv. e/mg Chl·h) was attributed to the activity of
non-assimilative electron flow. The ratio of total to assimilative electron flow was found to increase gradually with rising
in irradiance. The results suggest that non-assimilative electron flow occurred at much higher rate than assimilative electron
flow at high irradiance. Implications of the results are briefly discussed in relation to photosynthesis limitation in tree
leaves. 相似文献
65.
LIZhao-hua MikioKOBAYASHI 《林业研究》2004,15(3):233-242
In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which China‘s agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edibleshoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended. 相似文献
66.
Takuyuki Yoshioka Kazuhiro Aruga Toshio Nitami Hiroshi Kobayashi Hideo Sakai 《Journal of Forest Research》2005,10(2):125-134
Using the method of a life cycle inventory (LCI) analysis, the energy balance and the carbon dioxide (CO2) emission of logging residues from Japanese conventional forestry as alternative energy resources were analyzed over the entire life cycle of the residues. The fuel consumption for forestry machines was measured in field experiments for harvesting and transporting logging residues at forestry operating sites in Japan. In addition, a total audit of energy consumption was undertaken. It involved an assessment of materials, construction, and the repair and maintenance of forestry machines as well as the costs associated with an energy-conversion plant. As a result, the ratio of energy output to input was calculated to be 5.69, indicating that the system examined in this study could be feasible as an energy production system. The CO2 emission per MWhe (e: electricity) of the biomass-fired power generation plant was calculated to be 61.8kgCO2/MWhe, while that of coal-fired power generation plants in Japan is 960kgCO2/MWhe. Therefore, the reduction in the amount of CO2 emission that would result from replacing coal with biomass for power generation by as much as 3.0 million dry-t/year of logging residues in Japan was estimated to be 1.66 million tCO2/year, corresponding to 0.142% of the national CO2 emission. This study provides evidence that Japan could reduce its domestic CO2 emission by using logging residues as alternative energy resources. 相似文献
67.
This paper presents a probabilistic method of evaluating the final moisture content (MC) of lumber obtained at the end of the kiln-drying process. The final MC data of three different drying tests conducted in past studies were analyzed using the bootstrap method. Target MC was tentatively set below 20 % in the analysis. Two characteristic parameters representing the final MC were estimated with bootstrap confidence intervals. These parameters were the standard deviation (SD) and the percentage of the population that met the MC requirement of less than 20 % (P 20). The histograms of the final MC and the subsequent goodness-of-fit tests revealed that the final MC data of two drying tests did not follow any classical probability distributions, including Normal, Log-Normal, Weibull, and Gamma distributions, thus indicating the need for nonparametric statistics. The uncertainty of the final MC could be evaluated with the estimated SD and P 20. After deriving the relationships between P 20 and the corresponding probability that P 20 is not achieved, we demonstrated how such relationships could provide a kiln operator with information to facilitate better decision-making in optimizing a drying schedule. 相似文献
68.
Masaki Jinkawa Hirokazu Yamaguchi Kuniaki Furukawa Toshiaki Satake Hiroshi Kobayashi 《Journal of Forest Research》2006,11(2):77-88
For monorail systems, it is very important to ensure the safety of the ground structure. We developed a tram car for slopes
that utilizes the mechanism of the monorail and analyzed the stress of the ground structure that had double rails. First,
we divided the ground structure into seven components, and formulated a procedure for calculating the stress of the ground
structure. As a result, the stress that acts upon the main rail and the main rail connecting part was near the allowable stress,
and each calculated value was within the allowable stress. We measured the stress by running the vehicle, and compared the
measured values with the calculated values. As a result, some measured values were larger than the calculated values. However,
the ratio of measured value to allowable stress was 90% or less. Finally, we calculated the static loading coefficient for
each part, results of which were as follows: main and subrail: 1.1; rail connection part and prop foundation part: 1.0; rail
installation part: 1.3. In the recalculations, it became clear that the recalculated values exceeded the allowable stresses.
These results suggest that we need to review the ground structure materials. 相似文献
69.
Treatment by Sivanesan and Gibson (1976), that combined all species of Entomosporium into one species E. mespili (DC. ex Duby) Sacc, was supported through the investigation of many exsiccati and fresh specimens.Morphologically, all specimens and isolates of Entomosporium, which had been differentiated into 4 species, could not be divided into clearly separated groups.The fungus has been recorded on 50 host species and the disease is widespread throughout the world. 相似文献
70.
Yasutaka Watanabe Rie Mihara Tohru Mitsunaga Tsuyoshi Yoshimura 《Journal of Wood Science》2005,51(5):514-519
Fractions of methanol and ethanol extracts from the heartwood of white cypress pine (Callitris glaucophylla Thompson et Johnson) were investigated for their repellent activity against subterranean termite Coptotermes formosanus Shiraki worker using a two-choice semicircular filter paper test at 0.5% (w/w) concentration. Fraction CY-E2 composed of
(−)-citronellic acid, guaiol, α-, β-, and γ-eudesmol isomers as well as an unknown compound, showed the highest statistically significant repellency (97.8% ± 2.2 SEM)
of all fractions tested. Bioactivity-guided fractionations using high-performance liquid chromatography led to the isolation
of two, oxygenated eudesmane-type sesquiterpenes with α-methylene moieties, both termite-repellent compounds. These compounds were subsequently identified as ilicic acid methyl
ester (IAME) and costic acid by means of spectroscopic analyses, electron impact mass spectrometry, and nuclear magnetic resonance
spectroscopy. We report the isolation of both IAME and costic acid from C. glaucophylla heartwood for the first time.
Part of this paper was presented at the 47th Symposium on the Chemistry of Terpenes, Essential Oils, and Aromatics, Tokyo,
November 2003 相似文献