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51.
Setaria faberi and Digitaria ciliaris are summer annual grass weeds that constitute an orchard weed community in Japan. Species dominance in the weed community shifts from S. faberi to D. ciliaris with an emergence delay. The change in species dominance is assumed to be a clue to how weeds dominate or coexist in shaping the community. Population dynamics and seasonal variations in emergence and competitive ability were studied from this viewpoint. Field monitoring and pot experiments exhibited that the emergence period of the two species overlapped extensively from April to June. The emergence of S. faberi began 2 weeks earlier than that of D. ciliaris in April and declined in June as a result of the induction of secondary dormancy. The plant density of D. ciliaris was high during the whole period. The great mortality of the species was replenished with its great natality. The replacement series experiments revealed that S. faberi that had been planted in April was a better competitor than D. ciliaris, but it lost its competitive superiority in the June plantings, when D. ciliaris became a superior competitor to S. faberi. The level of seed output was greater for D. ciliaris, even when it was an inferior competitor. Therefore, the shift in species dominance appeared to be attributed to a change in competitive superiority between the two species. The early emergence of S. faberi and the high plant density of D. ciliaris might accelerate competitive exclusion. The two species coexist when they are equivalent in competitiveness. 相似文献
52.
Fiber quality is very important for all the steps of the textile area. Underwater shock wave has been utilized for metal,
wood, food processing and medical applications and renewed and increased application during the last decade. The main object
of this study, is to demonostrate underwater shock wave as a surface treatment of natural fibers such as jute and cotton in
form of yarn and to report characterized properties of the treated fibers. The underwater shock wave was generated by the
explosion of the detonation fuse in the water tank. The process of bubble generation and expansion inside the water results
in the formation of shock wave. Natural fibers were exposed to shock wave treatment depending on the different pressures and
detonatinon fuse separation distance. After shock-loading, fibers were selected for physicomechanical and physicochemical
tests such as Scaning Elecron Microscopy (SEM) analysis, breaking strength, moisture behavior, permeability and wicking test.
The maximum effect with improved moisture content, permeabilty and wicking properties were observed from 100 MPa. The treated
fiber showed high performance necessary for use in woven and non woven purpose. 相似文献
53.
Fukuma Yasufumi Yamane Akihiko Itoh Tomohiro Tsukamasa Yasuyuki Ando Masashi 《Fisheries Science》2012,78(2):451-461
Fish meat was brought to a supercooled state through slow cooling, and changes in the texture, histology, and protein composition
of the meat were investigated. The groups whose storage temperature were lowered by 1.0°C per day (the 1.0°C group) and 0.5°C
per day (the 0.5°C group) began to freeze in the vicinity of −3.5 and −5.0°C, respectively. The freezing point depended on
the fish species; the lowest freezing point was −8.5°C, for the red sea bream in the 1.0°C group. The breaking strength tended
to decrease more slowly in the 1.0°C group, but the collagen fibers collapsed more rapidly in the 1.0°C group. In SDS electrophoresis,
a slight change in the banding patterns was observed, but the relationship between this observation and changes in histology
and physical properties was unclear. This study shows that it is possible to produce a supercooled state in fish meat, and
demonstrates that supercooling is a potential new storage method that lowers the temperature without generating ice crystals. 相似文献
54.
Erwin Shuhei Takemoto Won-Joung Hwang Miyuki Takeuchi Takao Itoh Yuji Imamura 《Journal of Wood Science》2008,54(3):233-241
To further our understanding of wood decay in living light red meranti (Shorea smithiana) trees, microscopic characteristics of the cell and cell wall degradations of S. smithiana wood in the presence of the decay fungi, the identity of the causal fungi, and the decay potential and pattern by an isolated
fungus were investigated. Cell wall degradations, including cell wall thinning, bore holes formation, rounded pit erosion,
and eroded channel opening were clearly observed under light and scanning electron microscopy. In transverse view, many large
voids resulting from a coalition of degraded wood tissue appeared in the decayed canker zone. All these observations suggest
the well-known simultaneous decay pattern caused by white-rot fungi. By phylogenetic analysis based on the sequences of internal
transcribed spacer region of ribosomal DNA, a basidiomycete fungus isolated from the decayed wood was identified as Schizophyllum commune. The degradation caused by this fungus on sound S. smithiana wood in an in situ laboratory decay test was classified as the early stage of simultaneous decay, and showed a similar pattern
to that observed in the wood samples naturally decayed. 相似文献
55.
Toshiyuki Usami Mizuho Itoh Yoshimiki Amemiya 《Journal of General Plant Pathology》2009,75(6):422-427
Verticillium dahliae, a soilborne plant pathogen, causes wilt disease in many important crops. We reported previously that the mating type gene
MAT1-2-1 is spread to isolates of this asexual fungus. However, we did not determine whether V. dahliae is homothallic or heterothallic because the opposite mating type gene, MAT1-1-1, had not been identified. In the present study, we identified the MAT1-1-1 gene from an isolate lacking MAT1-2-1 and the mating type idiomorphs of V. dahliae. Each isolate we tested contained either the MAT1-1 or MAT1-2 idiomorph, indicating that the asexual fungus V. dahliae is potentially heterothallic. 相似文献
56.
Munekazu Nakaichi Toshie Iseri Hiro Horikirizono Harumichi Itoh Hiroshi Sunahara Yuki Nemoto Kazuhito Itamoto Kenji Tani 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(6):633
The pedigrees of 3 Dalmatian dogs afflicted with copper-associated hepatitis were investigated to discover the mode of inheritance. A composite family pedigree showed that the 3 affected Dalmatians were related. None of the parents of the affected dogs showed clinical symptoms of liver disease, and the disease had no sex predisposition. The estimated segregation ratio was approximately 3:1 based on surviving littermates. These findings suggested that the copper-associated hepatitis in these Dalmatians was an autosomal recessive mode of inheritance. In addition, some male Dalmatians imported from abroad might have been involved in the occurrence of this disease in Japan. 相似文献
57.
Keita W. Suzuki Taiki Fuji Akihide Kasai Sachihiko Itoh Shingo Kimura Yoh Yamashita 《Fisheries Oceanography》2020,29(1):66-83
Northwesterly cold winds characteristic of the East Asian Winter Monsoon (EAWM) dictate winter climatic conditions over the Japanese Archipelago. Japanese temperate bass Lateolabrax japonicus is a commercially important coastal fish that spawns offshore in winter and uses shallow waters as nursery habitats. To investigate the effects of EAWM on the planktonic period of L. japonicus, eggs, larvae, and juveniles were quantitatively collected in Tango Bay on the Sea of Japan side in winter and spring from 2007 to 2017. Although eggs occurred close to the mouth of the bay, planktonic larvae occurred further inside as they developed. The horizontal distribution of planktonic larvae, combined with water velocity data obtained from mooring observations, indicated that planktonic larvae are transported south‐ to westward through Ekman current and an anticyclonic circulation, which are driven by northwesterly winds. To evaluate survival during the planktonic period in each year class, the abundance of benthic larvae/juveniles was divided by winter total landings of Lateolabrax spp. (proxy of the spawning stock size). This survival index exhibited a positive correlation with the northwesterly component of winter winds, and a negative correlation with winter air temperature (average from December to February, Spearman's correlation, p < .05). There was, however, no significant correlation with winter water temperature or winter freshwater discharge in the bay. We conclude that northwesterly cold winds of EAWM play a critical role in transporting L. japonicus eggs and larvae toward nursery habitats, specifically beaches and estuaries fringing the innermost part of Tango Bay. 相似文献
58.
Relationship between serum TNF activity and insulin resistance in dairy cows affected with naturally occurring fatty liver 总被引:2,自引:0,他引:2
Ohtsuka H Koiwa M Hatsugaya A Kudo K Hoshi F Itoh N Yokota H Okada H Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):1021-1025
To clarity the relationship between tumor necrosis factor (TNF) and insulin resistance in dairy cows affected with fatty liver, naturally occurring cases were investigated. The affected cows were classified into following three groups according to histopathologic findings of the liver: mild fat droplet deposition (group 1; n=11), severe fat droplet deposition (group 2; n=10), and cloudy swelling (group 3; n=8). Serum TNF activities in Group 2 (8.67 +/- 2.16 U/ml) and Group 3 (11.65 +/- 1.92 U/ml) were significantly higher than that in Group 1 (3.57 +/- 0.81 U/ml) (p<0.05). The insulin-tolerance tests showed that the insulin-stimulated glucose disposal rates (GDR) in Group 2 (27.6 +/- 7.8%) and Group 3 (15.8 +/- 9.1%) were significantly lower than that in Group 1 (41.7 +/- 9.8%). There was a significant negative correlation between serum TNF activity and GDR in affected cows (r=-0.56, p<0.01). These results indicate that serum TNF activity is correlated with insulin resistance in cows with fatty liver. 相似文献
59.
Dehydrins are proteins associated with conditions affecting the water status of plant cells, such as drought, salinity, freezing and seed maturation. Although the function of dehydrins remains unknown, it is hypothesized that they stabilize membranes and macromolecules during cellular dehydration. Red-osier dogwood (Cornus sericea L.), an extremely freeze-tolerant woody plant, accumulates dehydrin-like proteins during cold acclimation and the presence of these proteins is correlated with increased freeze tolerance (Karlson 2001, Sarnighausen et al. 2002, Karlson et al. 2003). Our objective was to determine the location of dehydrins in cold-acclimated C. sericea stems in an effort to provide insight into their potential role in the freeze tolerance of this extremely cold hardy species. Abundant labeling was observed in the nucleus and cytoplasm of cold-acclimated C. sericea stem cells. In addition, labeling was observed in association with plasmodesmata of cold-acclimated vascular cambium cells. The unique association of dehydrin-like proteins with plasmodesmata has not been reported previously. 相似文献
60.
Ota T Itoh A Tachi H Kudoh K Watanabe T Yamamoto Y Tadokoro T Maekawa A 《Journal of agricultural and food chemistry》2005,53(15):6112-6116
Morphiceptin (Tyr-Pro-Phe-Pro-NH(2)), tetrapeptide, was synthesized using dipeptidyl aminopeptidase IV (DP IV, EC 3.4.14.5) derived from Aspergillus oryzae RIB 915 as a catalyst. Tyr-Pro-OEt was incubated with Phe-Pro-NH(2) in the presence of DP IV under various conditions of temperature, concentrations of ethylene glycol, pH, reaction time, and others. Morphiceptin was obtained at 40% yield under the optimal reaction conditions: substrate, 4 mM Tyr-Pro-OEt.HCl and 20 mM Phe-Pro-NH(2).HCl; enzyme, DP IV, 0.275 nkat; solvent, 60% ethylene glycol containing 20 mM phosphate buffer at pH 7.0; amine, 4.2 mM diisopropylamine at 4 degrees C for 24 h. Amino group protection was unnecessary for synthesis of morphiceptin by DP IV. 相似文献