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131.
Shin-ichi Miyata Hiroshi Kato Richard Davis Malcolm W. Smith Matthew Weinert Toru Iwanami 《Journal of General Plant Pathology》2011,77(1):43-47
‘Candidatus Liberibacter asiaticus’ is the most widespread of the three species of ‘Ca. Liberibacter’ that cause citrus greening disease (huanglongbing). To ascertain the phylogenetic relationships among Indian
isolates that have higher diversity in the 16S rDNA than Asian isolates of this species, we collected symptomatic leaves from
Northeast India, Papua New Guinea and Timor-Leste (East Timor) and detected ‘Ca. L. asiaticus’ by PCR using primers specific for nusG–rplK genes and 16S rDNA. Phylogenetic analysis with 16S rDNA sequences and single nucleotide polymorphisms of the omp gene region revealed that the Northeast Indian isolates were genetically closer to Asian-common isolates from Japan, Taiwan,
and Vietnam than to Indian isolates reported previously. Thus, the Asian-common strains of ‘Ca. L. asiaticus’ are apparently also present in Northeast India. 相似文献
132.
Yoshihiro Hata Takuto Hashiba Takashi Nakamura Masashi Kitamura Takahide A. Ishida Shin-ichi Akimoto Hiroaki Sato Masahito T. Kimura 《Journal of Forest Research》2011,16(4):309-318
Leafminer (Phyllonorycter, Gracillariidae, Lepidoptera) and aphid (Tuberculatus, Aphididae, Hemiptera) composition were studied in three deciduous oak species, Quercus dentata, Q. crispula, and Q. serrata, and their hybrids in Tomakomai Experimental Forest of Hokkaido University, Hokkaido, northern Japan. Identification of trees
in this forest was done mainly on the basis of discriminant analysis on leaf morphology with reference to trees in pure Q. dentata and Q. crispula stands and a Q. serrata stand mixed with Q. crispula. The results suggested that hybridization occurred in all combinations (i.e. Q. dentata–Q. crispula, Q. crispula–Q. serrata, and Q. serrata–Q. dentata) and the frequency of hybrids was approximately 10%. The composition of Phyllonorycter and Tuberculatus species differed between Q. dentata and Q. crispula or Q. serrata, but did not differ between Q. crispula and Q. serrata. Thus, Q. dentata could differ from Q. crispula and Q. serrata in chemical properties that determine herbivore host selection, survival, and performance, possibly reflecting eco-physiological
differences or phylogenetic distances. The study insects were divided into three groups: species specialized to Q. dentata (three Phyllonorycter and one Tuberculatus species), those to Q. crispula and Q. serrata (six Phyllonorycter and two Tuberculatus species), and a species collected at least from Q. dentata and Q. crispula (one Tuberculatus species). Putative hybrid trees of Q. dentata and Q. crispula harbored both Q. dentata-specific and Q. crispula-specific insects. 相似文献
133.
134.
Takashi Yokota Reiji Masuda Hiroyuki Takeuchi Tatsuo Tsuzaki Nobuaki Arai 《Fisheries Science》2007,73(3):500-511
ABSTRACT: To determine characteristics which may reflect the behavioral quality of red tilefish Branchiostegus japonicus after release, five wild and four hatchery-reared fish were observed in a laboratory and in the sea. The diel activity of the fish was recorded on video tape for 2 days in a tank, where the light condition was regulated to vary periodically over 24 h. The individuals were then released in Maizuru Bay and tracked using acoustic telemetry. Four wild individuals became most active at dawn during a day in the tank, and settled near the release area to stay for 28–104 days after release in Maizuru Bay. In contrast, one wild and four hatchery-reared individuals were not active at dawn, and then did not settle in Maizuru Bay after release. Among the four settled wild individuals, the more active a fish had been in the tank, the more distant the individual moved from the release point until its settlement. The diel activity pattern should be a factor deciding whether red tilefish would settle nearby after release, and the relative amount of activity during rearing is probably related to the degree of dispersion within the release area. 相似文献
135.
The phenomenon of hydraulic fracturing is considered to be one of the causes of leakage in fill-type dams. In recent years, it has been found that an estimate of the fracture toughness of a given type of soil could be used as an indicator of the soils resistance to hydraulic fracturing. One of the problems encountered in its estimation is the assumption that fracture toughness has been theoretically defined for samples of infinite sizes. In this study, laboratory tests were conducted to determine the fracture toughness of samples (of the same size) prepared with initial cracks of various lengths. The main objective was to investigate the relationship of the initial crack length to fracture toughness. The stress distribution around the crack tip for each laboratory test sample was estimated by FEM analysis and by a theoretical equation. These analytical results corresponded reasonably well to results from laboratory tests to determine the appropriate length of the initial crack for the test specimens. 相似文献
136.
K. Inoue N. Oyama S. Kondo Y. Hayata H. Yokota 《The Journal of Horticultural Science and Biotechnology》2013,88(5):681-686
SummaryAn economic assessment was made of whether leaf vegetables can absorb almost all of a given amount of an L-ascorbic acid solution applied by soaking the roots for 12 h. The effects of storage temperature on the foliar exogenous ascorbic acid content were also observed. It was found that the given amounts of L-ascorbic acid solution are entirely absorbed by lettuce plants (Lactuca sativa L., cv. Redfire) and are over 90% absorbed by spinach (Spinacio olerácea L., cv. Read) and bunching onion plants (Allium fistulosum L., cv. Hakata Kuronegi). Due to the soaking treatment, the sum of the L-ascorbic acid (AA) and dehydro-ascorbic acid (DHA) contents (mg per 100 g fresh weight) in the leaves of plants which showed no signs of wilting increased from 38.9 to 201–221 in lettuce, from 76.5 to 196–225 in spinach and from 46.7 to 134–144 in bunching onion. The foliar AA content in all the plants stayed at approximately the same value during a storage period of 7 d at 4°C, but decreased significantly at 25°C. The foliar DHA content in all of the plants stayed at approximately the same value during storage at both 4 and 25°C. These results suggest that the ascorbic acid introduced into leaf vegetables can be used effectively by consumers when the vegetables are stored at low temperature. 相似文献
137.
Yosuke Kikuchi Satomi Nozaki Miki Makita Shoji Yokozuka Shin-ichi Fukudome Takashi Yanagisawa Seiichiro Aoe 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):161-165
Metabolic syndrome is a risk factor for cardiovascular diseases and has become increasingly common in Japan. Epidemiological studies show inverse associations between intake of whole wheat grains and metabolic syndrome, but few dietary intervention trials have investigated the effect of whole wheat grain consumption. It was investigated whether a diet in which refined wheat bread (RW diet) was substituted by whole grain wheat bread (WW diet) would reduce visceral fat obesity in Japanese subjects. A randomized double-blind placebo-controlled intervention study was conducted in 50 Japanese subjects with body mass index (BMI)?≥?23 kg/m2. Subjects were randomly assigned WW (WW group) or RW diets (RW group) for 12 weeks. Blood samples and computed tomography scans were obtained every 6th week. The WW group showed decrease (?4 cm2) in visceral fat area (VFA) (p <?0.05), whereas the RW group showed no significant changes. These time-dependent changes were significantly different between the groups. WW diet led to significant and safe reductions in VFA in subjects with BMI?≥?23 kg/m2. WW diet may contribute to preventing visceral fat obesity. 相似文献
138.
139.
Wulansari R Wijaya A Ano H Horii Y Nasu T Yamane S Makimura S 《Journal of the American Animal Hospital Association》2003,39(6):558-562
This report examines the effectiveness of clindamycin for the treatment of babesiosis in dogs (n=10) experimentally infected with Babesia gibsoni (B. gibsoni). Clindamycin (25 mg/kg body weight, per os, q 12 hours for 14 days) gradually reduced parasitemia levels and induced morphological changes that indicated degeneration of parasites (e.g., segmentation; size reduction; localization in the cell limbic and/or torn state of the nucleus; and swelling, decrease, or disappearance of the cytoplasm) in the majority of dogs. Clindamycin treatment reduced the clinical symptoms characteristic of Babesia infection, including anemia, anorexia, and listlessness. Clindamycin might be useful as a medicine for treatment of B. gibsoni infection. 相似文献
140.
Toru?KondoEmail author Dong-Kyoon?Kang Shin-ichi?Fuji Moo-Ung?Chang 《Journal of General Plant Pathology》2003,69(6):397-399
Sixteen isolates of Chinese yam necrotic mosaic virus (ChYNMV) were collected from nine sites in Japan and one site in Korea, and 1098 nucleotides of the 3-terminal of the genome were sequenced. Identity of the coat protein gene was 95.5%–99.7% among the isolates. Substitution in the deduced amino acids of the coat protein ranged from 0 to 7, mainly in the N-terminal region. The 3-untranslated region consisted of 231 nucleotides, which had 96.5%–100% nucleotide identity among the isolates. Sequence diversity was considerably less in ChYNMV than in Yam mosaic virus or Japanese yam mosaic virus. 相似文献