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121.
ABSTRACT:   Acoustic survey and a geographic information system (GIS) were used conjointly to estimate the significance of bottom substrate to explain fish abundance distribution in the complex topography context of a marine hill. The survey was conducted in the Hachirigase hill, off south-western Honshu Island in the Sea of Japan. Analysis of acoustic data focused on a 10-m thick layer beginning at the bottom, assuming that bottom influence does not exceed this distance. Area backscattering strength ( S a ) values were rescaled in order to reflect real differences before being analyzed. Results show that the influence of the different parameters taken into account (bottom depth, bottom substrate and water temperature) varies widely from one place to another. Bottom substrate is above all important in the zone located to the west of the peak. The kriging and stratification methods were applied to the S a distribution for estimating the total S a in the hill. Differences between results are discussed. Conjoint use of acoustic survey and GIS is an effective method for analyzing and estimating fish abundance distribution in a marine hill.  相似文献   
122.
Previous studies reported that some genotypes with introgressed Festuca chromosome segment(s) in Lolium genome showed enhanced winter hardiness compared to Lolium. The aim of this study was to search comprehensively for the Festuca pratensis chromosome regions affecting winter hardiness-related traits when introgressed into the Lolium perenne genome. Association between F. pratensis introgression and winter hardiness-related traits (fall and winter hardiness indexes, early-spring dry matter yield, and freezing tolerance) were screened in the diploid introgression populations (n = 203) that had some F. pratensis chromosome segments introgressed. Eighty-four intron markers corresponding to unique rice genes randomly distributed across the genome were used for genotyping. Winter hardiness of almost all plants in the introgression populations was lower than that of the F. pratensis and triploid hybrid parents, but the average was higher than that of L. perenne. A significant positive effect of F. pratensis introgression on early-spring dry matter yield was detected on chromosome 7. This quantitative trait locus (QTL) was confirmed by linkage analysis using a backcross population with F. pratensis introgression in the target region of chromosome 7. However, the contribution of the newly identified QTL was rather small (6.7–9.6%), suggesting that superior winter hardiness of F. pratensis compared to L. perenne is conferred by multiple small-effect QTLs. We also detected a previously unreported negative effect of Festuca introgression on winter hardiness. Newly obtained QTL information in this study would contribute to the design of Festuca/Lolium hybrid breeding.  相似文献   
123.
Phytoplasma-induced floral malformations such as virescence, phyllody, and proliferation were observed on hydrangeas in Gunma Prefecture, Japan. Phylogenetic analyses based on 16S rRNA, secY, groEL, and amp gene sequences indicated that the affected hydrangea plants were associated with phytoplasmas belonging to ‘Candidatus Phytoplasma asteris’, but not to ‘Ca. P. japonicum’, which occurs in hydrangeas showing phyllody in Japan. This is the first molecular evidence of an association of ‘Ca. P. asteris’ with hydrangea plants in Japan.  相似文献   
124.
A viroid was detected for the first time in symptomless petunia plants (Petunia spp.) and identified as Tomato chlorotic dwarf viroid (TCDVd) based on an analysis of the complete genomic sequence. These petunia plants are a likely source of inoculum for tomato or potato plants because TCDVd induces severe symptoms on these plants. The genomic sequence of this petunia isolate from Japan shared 100 % identity with petunia isolates from the Netherlands and United Kingdom and a tomato isolate from Japan. Phylogenetic analysis showed that all petunia isolates and the tomato isolate from Japan formed a monophyletic clade.  相似文献   
125.
Plasma insulin (INS), thyroxin (T4), glucose (GLU), non‐esterified fatty acid (NEFA), blood urea nitrogen (BUN), rectal temperature (RT) and eating behavior were evaluated in Japanese Shorthorn cattle under varying external environments and management techniques. Serial blood collection and assessments of RT and eating behavior were performed over 48 h in the spring, summer, autumn and winter in four female cattle reared under either free‐stall and ad libitum feeding (FA) conditions or tie‐stall and restricted feeding (TR) conditions. Cycle patterns for each parameter were examined using spectral analysis, and correlations between parameters were investigated using cross‐spectral analysis. Rhythms for all parameters, except eating behavior and T4, did not differ significantly among the varied external environments and between management techniques, although seasonal differences in the concentration or value of parameters were observed. An approximate 3‐ or 4‐h rhythm cycle detected in T4, GLU, NEFA, BUN, and RT might be the common metabolic rhythm. Under both conditions, the metabolite levels showed strong correlations with eating behavior. Moreover, GLU positively correlated with INS at lag time of 0 h, as did eating behavior and RT.  相似文献   
126.
Two new cytotoxic twelve-membered macrolides, sporiolides A (1) and B (2), were isolated from the cultured broth of a fungus Cladosporium sp., which was separated from an Okinawan marine brown alga Actinotrichia fragilis, and the structures were elucidated by spectroscopic data. Sporiolides A (1) and B (2) exhibited cytotoxicity against murine lymphoma L1210 cells. Spoliolide A (1) showed antifungal activity against Cryptococcus neoformans and Neurospora crassa.  相似文献   
127.
To compare the responses to repeated flooding and drought of Salix gracilistyla, which grows on coarse gravel substrates, and Salix subfragilis, which grows on fine silt or clay substrates, we measured pre-dawn leaf water potential (Ψw pd), osmotic adjustment (Ψw tlp, Ψo sat), and biomass production of cuttings under greenhouse conditions. The experimental design involved a control and four treatments that crossed 1 or 3-week flooding (F) with 1 or 2-week droughts (D). Ψw pd was reduced after 2 weeks of drought when preceded by 1 week of flooding. Neither species increased osmotic adjustment in response to increased duration of drought between repeated 3-week flooding. Moreover, a decrease in the ratio of leaf biomass to total biomass or an increase in the ratio of root biomass to total biomass with longer drought repetitions was not observed for either species. The root ratio of S. gracilistyla was more strongly inhibited by flooding than that of S. subfragilis. The shoot-to-root ratio of S. subfragilis was higher than that of S. gracilistyla in all F combinations. The hypertrophied lenticel ratio of S. gracilistyla after 1 week of flooding was nearly the same as that after 3 weeks of flooding, whereas values for S. subfragilis after 1 week of flooding were lower than those after 3 weeks of flooding. The low allocation to roots and the generation of hypertrophied lenticels by S. gracilistyla in response to flooding, as compared with S. subfragilis, seem to be related to the different habitat substrate conditions of the two species.  相似文献   
128.
The displacement and signal intensity (SI) of the pituitary posterior lobe were evaluated on T1 weighted magnetic resonance (MR) images in 28 dogs with pituitary dependent hyperadrenocorticism (PDH). Compared with normal dogs, the posterior lobe was displaced dorsally in the pituitary of the PDH dogs. Correlation between the pituitary height/brain area (P/B) ratio and the displacement of the posterior lobe in the PDH dogs suggests that dorsal displacement of the posterior lobe increases in accordance with enlargement of the pituitary. As to the SI of the posterior lobe, the PDH dogs showed significantly lower SI in comparison to the normal dogs. Taken together, these results suggest that assessment of the displacement and SI of the posterior lobe of the pituitary on T1-weighted MR images is useful for the diagnosis of pituitary adenoma. In pituitary microadenoma that presents no apparent tumorigenesis on MRI, evaluation of these values may be useful for diagnosis and selection of an appropriate therapy.  相似文献   
129.
Several wood-based sandwich panels with low-density fiberboard core were developed for structural insulated walls and floors, with different face material, panel thickness, and core density. The elastic moduli with and without shear effect (E L, E 0) and shear modulus (Gb) were evaluated in four-point bending. Generally, the stiffer face, thicker panel, and higher core density were advantageous in flexural and shear rigidity for structural use, but the weight control was critical for insulation. Therefore, optimum designs of some virtual sandwich structures were analyzed for bending stiffness in relation to weight for fixed core densities, considering the manufactured-panel designs. As a result, the plywood-faced sandwich panel with a panel thickness of 95 mm (PSW-T100), with insulation performance that had been previously confirmed, was most advantageous at a panel density of 430 kg/m3, showing the highest flexural rigidity (E L I = 13 × 10−6 GNm2) among these panels, where E L, E 0, and G b were 3.5, 5.5, and 0.038 GN/m2, respectively. The panel was found to be closest to the optimum design, which meant that its core and face thickness were optimum for stiffness with minimum density. The panel also provided enough internal bond strength and an excellent dimensional stability. The panel was the most feasible for structural insulation use with the weight-saving structure.  相似文献   
130.
A new C-glucoside of epsilon-viniferin, named diptoindonesin A (1), was isolated from the ethyl acetate extract of the tree bark of Shorea seminis, together with the known stilbene oligomers (-)-ampelopsin A (2), (-)-alpha-viniferin (3), and (-)-hopeaphenol (4). The structure of 1 was determined from spectroscopic evidence.  相似文献   
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