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91.
In order to investigate the impact of climate change on egg and larval transport of Japanese anchovy (Engraulis japonicus) off Kyushu Island western Japan, we conducted particle‐tracking simulations on transport success/failure to fishing grounds from 1960 to 2007. The modeled transport success since the mid‐1990s increased and decreased in the offshore and coastal zones, respectively, compared with the 1960s and 1970s. The estimated northward shift of the spawning ground and weakened Tsushima Warm Current contributed to increase in modeled transport success to the offshore zone. Conversely, the weakening trend of the modeled onshore current in the Goto‐Nada Sea combined with the northward shift of the spawning ground resulted in unsuccessful larval transport. These results suggest that fluctuations in juvenile and subadult anchovy catches in this area may be attributable to changes in the physical environment. The present study showed that changes in transport success induced by oceanographic fluctuations related to climate change, have the potential to affect anchovy recruitment off the western coast of Japan.  相似文献   
92.
In early January 2015–2017, anthracnose was detected on Satsuma mandarin orange (SMO) (Citrus unshiu) fruits kept in farmers’ storage rooms in Saga Prefecture, Japan. Three single-spore isolates from rotten fruits reproduced the postharvest anthracnose symptoms in wound-inoculated SMO fruits and were re-isolated from lesions. The isolates were identified as Colletotrichum fioriniae based on conidial morphology, culture characteristics, rDNA-ITS, and beta-tubulin-2 gene sequences. This is the first report of postharvest anthracnose on SMO caused by C. fioriniae.  相似文献   
93.
Effects of a one-generation exposure to a natural estrogen, 17beta-estradiol (E2), and environmental pollutants such as bisphenol A (BPA) and tributyltin chloride (TBTCL) on the number of germ cells were investigated in the hermaphrodite Caenorhabditis elegans. The eggs of gravid adult worms isolated by alkaline hypochlorite treatment were seeded on a test chemical-containing NGM (nematode growth medium) agar plate without cholesterol. After incubation for 6 days at 16 degrees C, the germ cells of adult worms were stained with 4', 6-diamino-2-phenylindole dihydrochloride (DAPI). The staining procedure was completed within one hour and the stained germ cells were counted under a fluorescence microscope without dissection. The number of germ cells in the worms treated with E2 (10(-10)-10(-6) M) and BPA (10(-9)-10 (-5) M) was significantly increased. Maximal increases were observed at 10(-8) M E2 (156 +/- 15.3% of control) and 10(-5) M BPA (168 +/- 20.0 % of control). TBTCL (10(-9)-10(-6) M) significantly decreased the number of germ cells. The minimal decrease was observed at 10(-6) M TBTCL (30.2 +/- 3.51% of control). These results indicate that changes in the number of germ cells are a sensitive indicator of the effects of chemicals on the reproductive system. Since the method described in this paper is a novel, simple, time- and money-saving bioassay, C. elegans is an excellent model with which to determine the reproductive toxicity of chemicals including environmental pollutants.  相似文献   
94.
A monoclonal antibody, named C302, was prepared and characterized against botulinum ADP-ribosyltransferase C3 exoenzyme that inactivates RhoA GTP-binding protein, resulting in the neurite outgrowth of human neuroblastoma GOTO cells. C302 bound not to the smaller fragments derived from the protease-treated C3 exoenzyme but to the intact C3 exoenzyme. It seems that the C302 epitope may depend on the three-dimensional structure of C3 exoenzyme molecule. C302 depressed the enzymatic and biological actions of C3 exoenzyme. The dose-dependent depression pattern of C302 on the enzyme activity was similar to that to the biological one. C302 turned the neurite-bearing shape of the C3 exoenzyme-treated GOTO cells into the intact shape. By using of C302 mAb and C3 exoenzyme, the research concerning GTP-binding proteins would be improved.  相似文献   
95.
 The coat protein (CP) gene of Mirafiori lettuce virus (MiLV), a tentative member of the genus Ophiovirus was isolated and sequenced. The established sequence consists of 1514 nucleotides including one open reading frame (ORF) with 1311 nucleotides that encodes 437 amino acids with a relative molecular mass 48 543. When the ORF was expressed in Escherichia coli, the obtained protein was confirmed as CP by Western blotting using an antiserum against MiLV. Database searches showed that the CP gene of MiLV has a sequence similar to that of Citrus psorosis virus (CPsV), the type species of the genus Ophiovirus. The comparison between MiLV and CPsV CP genes revealed that the identities of the nucleotide and amino acid sequences were 46.5% and 30.9%, respectively. Received: July 29, 2002 / Accepted: October 2, 2002  相似文献   
96.
Three experiments were performed to examine the effects of high ambient temperature and feed restrictions on urinary 3‐methylhistidine (3MH) excretion and plasma 3MH concentrations as a marker of myofibrillar proteolysis in lactating Holstein cows. In a crossover design, four cows were maintained during two 14‐day treatment periods with ad libitum feed intake under constant moderate (18°C) or high (28°C) ambient temperature (Experiment 1), with ad libitum or 70% ad libitum feed intake under constant moderate temperature (Experiment 2), and with 70% ad libitum feed intake under constant moderate or high ambient temperature (Experiment 3). The total digestible nutrients intake was decreased (P < 0.01) under high ambient temperature (Experiment 1) or feed restriction (Experiment 2). Across experiments, urinary 3MH excretion during days 10–14 of each treatment period was not different among treatments. However, the plasma 3MH concentrations at day 14 of treatment were increased significantly under high ambient temperature with subsequent reduced feeding (P < 0.01) or moderate temperature with feed restriction (P < 0.05), and were increased slightly (P = 0.11) under high ambient temperature alone. These results show that the plasma marker of myofibrillar proteolysis in lactating dairy cows was increased at day 14 of treatments of high ambient temperature with subsequent reduced feeding, moderate temperature with feed restriction, or high ambient temperature alone.  相似文献   
97.
Momordica charantia L. plants systemically infected with Cucumber mosaic virus (CMV) were found in Oita Prefecture. The virus isolated from the host plant was characterized by biological, serological, and molecular biological methods. The purified virus was used to mechanically inoculate the host and produced green mottle, green mosaic, and/or chlorotic spots in the noninoculated upper leaves of the host. The virus was identified as an isolate of CMV containing genomic RNA3 derived from subgroup IA by several lines of evidence based on electron microscopy, serological detection, host range, symptoms, and the entire nucleotide sequence of RNA3.  相似文献   
98.
Beetle samples captured by traps were compared with those captured manually on flowers in a beech forest in Central Japan. Plastic traps (Sankei Chemical Co., Ltd.) equipped with benzyl acetate were set up from the 2nd of June to the 8th of September 1994, and all beetles captured were collected every week. Beetles were also captured on wild flowers blooming along the forest road. The traps captured 21,650 individuals of 169 species in 37 families. On the other hand, 971 individuals of 77 species in 19 families were captured on the flowers. All of the families and 57 (74%) species of the beetles captured on the flowers were also captured by the traps; all of the species with more than five individuals captured on the flowers were also trapped, except for one species. The present trap system is considered to be useful for faunal monitoring of flower-visiting Coleoptera, because the beetle fauna found on wild flowers was virtually covered by the trap capture. A part of this paper was presented at the 106th Annual Meeting of the Japanese Forestry Society (1995).  相似文献   
99.
In this report, we undertook studies of the viscoelastic properties of wood from the viewpoint of the fine structure and properties of the constituent materials in the wood cell wall. To measure the mechanical properties of the wood as the behavior of the cell wall, it is required to perform the longitudinal tensile test using a homogeneous specimen. In this study, microtomed specimens of sugi (Cryptomeria japonica D.Don) earlywood were used for the creep test, which were conducted at the fiber saturation point. The substantial creep compliance of the cell wall was simulated using a simplified viscoelastic model consisting of a Voigt element and an independent spring in series. Based on the experimental results, the values of the parameters were optimized. The results were as follows: (1) the longitudinal tensile creep deformation tends to increase with the elapsed time, similar to the bending creep behavior; (2) the magnitude of the longitudinal creep function increases with MFA; and (3) each parameter in the simplified viscoelastic model is markedly affected by the MFA. Based on these results, the mechanism of the longitudinal tensile creep deformation of wood is discussed.  相似文献   
100.
In anAbies homolepis Sieb. et Zucc. forest at Matsumoto, Nagano Pref., cumulative damage byXylotrechus villioni (Villard) (Coleoptera: Cerambycidae) was observed on tree branches. Of the 14 major branches in one sample tree, six had cumulative damage by boring larvae, of which 3 had been bored by multiple larvae. No adult emergence holes were found on the whole tree, suggesting very low survivorship from boring larva to emerging adult. Galleries made by single larvae were often observed to be terminated by a depression apparently carved by a picid woodpecker, suggesting that they are important predators of the cerambycid. The manner of cicatrix formation with phloem tissue over the larval gallery in anAbies veitchii Lindl. branch at Mt. Fuji, Yamanashi Pref. is presented. Studies onXylotrechus villioni (Villard) (Coleoptera: Cerambycidae), a primary borer of coniferous trees in Japan (III). This work was presented at the 104th Annual Meeting of Japanese Forestry Society at Morioka (April, 1993) and 20th International Congress of Entomology at Firenze (August, 1996). This work is supported by a Grant-in-Aid for Scientific Research (No.02660163) from the Ministry of Education, Science, Sports, and Culture of Japan.  相似文献   
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