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51.
The results of elementary analysis of each fraction separated physically from each horizon of five forest soils were described. The biggest fraction was Lf2 (fresh litter) in L layers, Ff2 (>2 mm) or Ff2 (2-1 mm) is F layers and Hf4 in H layers. Of all the changes in various parameters which accompanied decomposition and humification, the change in C/N ratio was the most obvious; the C/N ratio for plant remains easily decreased to 25 or 30 during decomposition, but any further decrease in this value occurred with difficulty. It was specifically pointed out that Hf7 and Hf2 were fairly different materials from the other fractions. As for A horizons, both carbon and nitrogen contents increased, and CIN ratios decreased in the order of sand, silt and clay fractions. 相似文献
52.
Ground-dwelling beetle community in beech forests of Sado Island,Japan: comparison with the mainland
Island ecosystems differ from mainland ecosystems in their long-term isolation. On Sado Island, Japan, cattle grazing in the
past gradually changed forests into grasslands, thereby altering the diversity of indigenous insects. We compared ground-dwelling
beetle diversity on Sado Island to that on the nearby mainland. Contrary to previous reports, the island isolation effect
resulted in lower γ and β diversity than on the mainland, because of the low species richness of beetles with low dispersal
abilities. Few flightless beetles could invade Sado Island, even when the beech forests on the island were relatively adjacent
to those on the mainland. Such a history of ecosystem formation could be the general pattern for continental-island mountain
forests that were never connected to those of the mainland. We did not observe low α diversity of ground-dwelling beetles,
suggesting that the cattle grazing history of the island has not changed environmental conditions for ground-dwelling beetles
enough to reduce their diversity. In addition, cattle grazing increases the abundance of merdivorous insects by increasing
the abundance of their food resource.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
53.
Preparation of strongly acidic cation-exchange resins from gymnosperm acid hydrolysis lignin 总被引:1,自引:0,他引:1
The chemical preparation of strongly acidic cation-exchange resin from sulfuric acid lignin (Klason lignin) (SAL), a typical acid hydrolysis lignin, was investigated. Sulfonation of resinified SAL itself gave a resin with an ion-exchange capacity of 2.3 mEq/g. After resinification with formaldehyde, the phenolized SAL with a reactivep-hydroxyphenyl group yielded a resin with an ion-exchange capacity of 3.2 mEq/g. The latter capacity is superior to that of the corresponding commercial phenol-type resins (2–3 mEq/g), but did not reach the level of the corresponding commercial styrene-type resins (4-5 mEq/g).This paper was presented at the 43th Lignin Symposium, Fuchu, October 1998 相似文献
54.
55.
Wei-Qin Wang Tomohide Natsuaki Yoshitaka Kosaka Seiichi Okuda 《Journal of General Plant Pathology》2006,72(1):52-56
To identify possible sites of viral attenuation, the complete nucleotide sequences of two isolates of Zucchini yellow mosaic virus (ZYMV) were determined; a severe isolate Z5-1 and an attenuated isolate from Z5-1 (designated ZYMV-2002). The viral genome
of both isolates consisted of 9593 nucleotides in size and contained an open reading frame encoding a single polyprotein of
3080 amino acids. Comparison of the nucleotide sequences for Z5-1 and ZYMV-2002 revealed 14 nucleotide mutations, resulting
in seven amino acid substitutions with four in the HC-Pro region, two in the CI region, and one in the NIb region. These results
provide a genetic basis for future manipulation of the ZYMV reverse genetics system.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB188115
and AB188116 相似文献
56.
Yasuyuki TANAHASHI Ban WANG Yuri MURAKAMI Toshihiro UNNO Hayato MATSUYAMA Hiroshi NAGANO Seiichi KOMORI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):203-211
In order to investigate the effects of (SKF), which is a non-selective cationic channel blocker, on
K+ channel currents, we recorded currents through ATP sensitive K+ (IKATP),
voltage-gated K+ (IKv) and Ca2+ activated K+ channels
(IBK) in the absence and presence of SKF in single small intestinal myocytes of mice with
patch-clamp techniques. SKF (10 µM) reversibly abolished IKATP that was induced by
cromakalim (10 µM), which is a selective ATP sensitive K+ channel opener. These
inhibitory effects were induced in a concentration-dependent and voltage-independent manner. The 50%
inhibitory concentration (IC50) was 0.85 µM, which was obviously lower than that
reported for the muscarinic cationic current. In addition, SKF (1 µM ≈ the IC50
value in IKATP suppression) reversibly inhibited the IKv that was induced by repetitive
depolarizing pulses from −80 to 20 mV. However, the extent of the inhibitory effects was only ~30%. In
contrast, SKF (1 µM) had no significant effects on spontaneous transient IBK and
caffeine-induced IBK. These results indicated that SKF inhibited ATP sensitive K+
channels and voltage-gated K+ channels, with the ATP sensitive K+ channels being more
sensitive than the voltage-gated K+ channels. These inhibitory effects on K+ channels
should be considered when SKF is used as a cationic channel blocker. SKF96365相似文献
57.
The Cb value is a useful parameter for estimating the humidity control capacity of materials. It is defined as the ratio of the
range of variation of relative humidity in a steel box lined with the material of interest to that in an empty steel box,
when sinusoidal temperature variation is applied. However, because it takes a long time to obtain the Cb values for materials at each temperature variation period, we developed an easier method based on a linear excitation-response
theory to obtain the Cb values without measuring at each period. Japanese cedar was the material used in this study. The temperature excitation,
a jump from a constant temperature to another constant temperature, was used to obtain the absolute humidity response. Under
the assumption that the temperature excitation-humidity response relationship is linear, we were able to predict humidity
variation to sinusoidal temperature variation at any period, and we obtained the Cb value for each temperature variation period. Predicted values agreed well with the experimental values. From this, it was
found that the Cb value could be predicted without measuring the Cb value at each period over a long time. In addition, the peak time difference, which is closely related to the Cb value, could also be predicted in a similar manner. 相似文献
58.
Yasuyuki?MatsushitaEmail author Akihiro?Kakehi Shigeru?Miyawaki Seiichi?Yasuda 《Journal of Wood Science》2004,50(2):136-141
To elucidate the formation and chemical structures of water-soluble material in acid-soluble lignin (ASL), lignin aromatic nuclei model compounds of creosol (I) and 5-methoxycreosol (II) were reacted with xylose or xylan in the presence of apocynol as a counterpart for condensation in 72% sulfuric acid (SA). The reaction of I gave mainly condensation product. However, the condensation reaction of II with apocynol was suppressed because of steric hindrance from the methoxyl group, and II yielded a C-xyloside after refluxing in 3% SA together with condensation products. To obtain information on CHCl3-soluble material in ASL, model compounds of arylglycerol--aryl ethers with guaiacyl (VIII) and syringyl (X) nuclei were treated by the Klason procedure. VIII gave only insoluble polymerized product, while X gave insoluble polymerized product and CHCl3-soluble low molecular weight products, which were dissolved in 3% SA. These results prove earlier views that water-soluble material in ASL consists of condensation products formed from syringyl lignin and monosaccharide units in hemicellulose. In addition, the CHCl3-soluble material in ASL appears to be composed of low molecular weight degradation products from SA treatment of Klason lignin with the syringyl nucleus.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 and at the 47th Lignin Symposium, Fukuoka, October 2002, and was reviewed in Mokuzai Gakkaishi (2002) 48:55–62 相似文献
59.
Preparation of anion-exchange resins from pine sulfuric acid lignin,one of the acid hydrolysis lignins 总被引:4,自引:0,他引:4
To utilize acid hydrolysis lignin effectively, chemical conversion to anion-exchange resin was investigated by two methods. Sulfuric acid lignin (SAL) was selected as a typical acid hydrolysis lignin in this experiment. Because it is less reactive, SAL was phenolated with sulfuric acid catalyst to yield reactive phenolized SAL (P-SAL) with p-hydroxyphenyl nuclei. One method was the restricted resinification of P-SAL followed by the Mannich reaction with formaldehyde and dimethylamine to yield a weakly basic anion-exchange resin with an ion-exchange capacity of 2.4mEq/g. Another method was to react resinified P-SAL with glycidyltrimethylammonium chloride to yield a strongly basic anion-exchange resin with an ion-exchange capacity of 2.0mEq/g. The reaction of a simple P-SAL model compound with an epoxide suggested that the phenolic hydroxyl group of the p-hydroxyphenyl nucleus had slightly higher reactivity than that of the guaiacyl nucleus.Part of this report was presented at the 47th Lignin Symposium, Fukuoka, October 2002 相似文献
60.
Watanabe D Hirano T Sugimoto Y Ogata Y Abe S Ando T Ohtsuka H Kunieda T Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1251-1255
Blood examinations and genotyping of Factor XI (F11) were performed in growth retardation Japanese Black cattle and their dams. Genotyping of F11 revealed that the recessive homozygous and heterozygous genotype frequencies were 5.2% and 50.0% in the Claudin-16 (CL-16) deficiency group (n=58), 0% and 14.2% in the renal dysplasia group (n=7), 0% and 26.1% in the non-CL-16 deficiency nephritis group (n=23), 8.9% and 46.7% in the hypogenesis syndrome group (n=45), 6.2% and 25.0% in the neonatal weak calf syndrome group (n=32), 9.1% and 38.6% in the respective dams group (n=44), 0% and 23.1% in the normal cattle group (n=13), and 5.9% and 38.2% in total (n=222), respectively. These results showed that the carrier rate of F11 deficiency was high in Japanese Black cattle, and that the CL-16 deficiency, hypogenesis syndrome, neonatal weak calf syndrome, and dams groups had a large amount of recessive homozygous genotype than the other groups. No abnormal bleeding was observed clinically in the present study, and 4 of the recessive homozygous dams showed normal growth and parturition. 相似文献