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21.
The central few hundred parsecs of the Milky Way host a massive black hole and exhibit very violent gas motion and high temperatures in molecular gas. The origin of these properties has been a mystery for the past four decades. Wide-field imaging of the (12)CO (rotational quantum number J = 1 to 0) 2.6-millimeter spectrum has revealed huge loops of dense molecular gas with strong velocity dispersions in the galactic center. We present a magnetic flotation model to explain that the formation of the loops is due to magnetic buoyancy caused by the Parker instability. The model has the potential to offer a coherent explanation for the origin of the violent motion and extensive heating of the molecular gas in the galactic center.  相似文献   
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23.
A 6-year-old male cynomolgus monkey showed chronic wasting. No gross abnormalities were observed in necropsy except for changes secondary to wasting. Microscopic examination revealed pigment granules deposition in systemic smooth muscles. They were observed as brown or basophilic in hematoxylin and eosin stain, and were positive for periodic acid-Schiff, Schmorl and Ziehl-Neelsen. Ultrastructurally, they consisted of residual bodies surrounded with varying amounts of solitary ribosomes. Thus, these granules were considered as lipofuscin. Unlike brown bowel syndrome in humans, the pigment granules were distributed systemically not only in the digestive tract but also in the blood vessels predominantly in the veins. To our knowledge, this is the first report on vascular smooth muscle lipofuscinosis occurring predominantly in the veins of primates.  相似文献   
24.
In tomato production, salt stress is applied to improve the fruit quality. The change in sensory attributes and organoleptic compositions in salt-stressed tomato fruits have been extensively studied; however, little is known about their interaction with each other. Correlation network analysis provides a visual representation of biological systems and useful knowledge for metabolic data analysis of tomato fruits. The aim of this study is to identify the cultivar differences in sensory attributes and organoleptic compositions of tomato fruits grown under salt stress and to elucidate their interaction among different cultivars using correlation network analysis. Salt stress was applied by adding 100 mM NaCl to the nutrient solution. Fruits were harvested at red-ripe stage and used for the evaluation of sensory attributes such as sweetness, sourness, umami, and tomato like, and organoleptic compositions such as sugar, organic acid, amino acid, and sodium ion contents. Almost all of the sensory attributes and organoleptic compositions of the fruit were significantly high in salt-stressed cultivars compared to non-stressed cultivars, and significant differences were also observed among cultivars. The correlation network analysis of the control fruit showed that compared to other traits, sugar is one of the key traits for improvement of tomato fruit quality based on high connectivity and betweenness centrality. In contrast, a high degree of positive connectivity was not observed between organoleptic compositions and sensory attributes in the salt-stressed fruit network. These results indicate that the relationship between sensory attributes and organoleptic compositions in fruits were different between the control and salt-stressed cultivars, suggesting that the salt-stressed fruit may have a different circuit of relationship compared to control. Furthermore, based on the increase ratio (salt stress/control) network results, we suggest that the increased sugar, organic acid, and amino acid contents may have contributed to the salt stress-induced enhancement of sensory attributes.  相似文献   
25.
The spatial variability of nitrogen (N) mineralization, nitrification, and microbial biomass was investigated using surface soils from various topographic positions at a relatively small watershed with Japanese cedar (Crgptomeria japonica D. Don) plantations. The watershed topography was characterized using a topographic index derived from GIS analysis. The topographic index reasonably reflected the spatial variability of the soil water conditions, total soil carbon (C) and N contents, and exchangeable base concentrations. However, this index was not significantly correlated with the spatial variability of net N mineralization and microbial biomass. Topographic index and soil properties (total soil C and N contents, C / N ratio, exchangeable base concentrations, and clay content) were subjected to principal component analysis to eliminate multiple-collinearity among the variables, and express the variables as new orthogonal variables. Principal component analysis showed that the soil properties could be divided into two groups: PC1 (soil nutrient pools) and PC2 (soil clay content). The topographic index was closely correlated with PC1 and not significantly correlated with PC2. Regression of PC scores on net N mineralization and microbial biomass indicated the relatively high contribution of PC2 to the variability in N mineralization and microbial biomass. This result suggested that not only topographic factors but also the clay content exerted an important influence on the spatial pattern of N mineralization and microbial biomass within a watershed with single species forests.  相似文献   
26.
ABSTRACT:   Year-round change in gelation of bassy chub ( Kyphosus lembus ) meat, collected from October 2001 to September 2002 off the coast of Nagasaki, was investigated. The fish meat exhibited a similar high gel-forming ability for all seasons, including pre- and post-spawning seasons. Freshwater washing of the meat did not improve its gel-forming ability. It was concluded that bassy chub meat could be used for thermal gel production in all seasons.  相似文献   
27.
The use of Bacillus spp. K-C3, isolated from commercial Kapi, salted shrimp paste of Thailand, as the starter culture for Kapi production, at different levels including 102, 104, and 106 CFU/g dry weight sample named Kapi-B2, Kapi-B4, and Kapi-B6, respectively, in comparison with naturally fermented Kapi (Kapi-C) was studied. All inoculated samples exhibited higher extent of proteolysis and lipolysis as indicated by higher trichloroacetic acid (TCA)-soluble peptide, degree of hydrolysis, and free fatty acid content in the final products. The greater rate of fermentation in the inoculated samples directly affected characteristics of Kapi and yielded Kapi with browner color and enhanced lipid oxidation as indicated by peroxide value (PV) and thiobarbituric acid reactive substance (TBARS) values. Increased antioxidative properties, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, and ferric reducing antioxidant power (FRAP), were obtained in Kapi with added inoculum. Moreover, those inoculated samples also contained higher intensity of volatile compounds, in which N-containing compounds, mainly pyrazine derivatives, were dominant. Kapi-B4 and Kapi-B6 showed the highest extent of these aforementioned values compared with Kapi-C and Kapi-B2. Therefore, inoculation with Bacillus spp. K-C3 at the level higher than 104 CFU/g dry weight sample is a potential means to accelerate the fermentation rate and yielded Kapi with preferable characteristics.  相似文献   
28.
Plug seedlings, widely used in cabbage cultivation in Japan, are often infected by seed-borne pathogens, especially the serious pathogen Alternaria brassicicola. Because information on seed infestation is scant in Japan, we investigated fungal infestation in commercial batches of cabbage seeds produced between 1984 and 2001. A total of 123 lots were divided into six groups by production period (1984–1989, 1994–1998, and 2001) and by use or nonuse of fungicide. One hundred seeds from each lot were incubated separately on agar at 25°C to isolate the predominant fungus. Alternaria brassicicola was isolated most frequently, 0%–94% of the seeds depending on seed lot or 6%–21% of the seeds grouped by production period and fungicide treatment. Thus, the pathogen was isolated even from seeds refrigerated for 17 years. Alternaria brassicicola accounted for 57%–95% of all isolated fungi by the group and was higher on older or fungicide-treated seeds. Seeds that were not treated with fungicide in lots grouped by production districts in western Japan were infested with A. brassicicola at a rate of over 12%, higher than that in the eastern region (<4%). Infestation was higher in the warmer areas of Japan. Eighty-five isolates, other than A. brassicicola, produced spots on cabbage cotyledons, although they were not isolated as frequently: less than 5% of seeds by group separated by production period and fungicide treatment. Most of these isolates were Alternaria alternata. This is the first report on the frequency of fungal infestation of commercial cabbage seeds in Japan.  相似文献   
29.
Digital terrain modeling and spatial climatic data have been used to estimate the spatial distribution of Japanese cedar (Cryptomeria japonica D. Don) forest productivity on a regional-scale. The study was conducted on Japanese cedar forests in Himi city, Oyabe city, Takaoka city, and Imizu city (a total area of 683 km2) in northwestern Toyama Prefecture. On the basis of data from 146 sample stands, above-ground net primary productivity (ANPP) was calculated from tree height, age, and density using existing ANPP conversion equations for Japanese cedar stands. Six topographic factors (slope, profile curvature, plan curvature, openness, wetness index, and topographic radiation index) were calculated from a 10-m cell size digital elevation model. Three climatic factors (annual mean temperature, annual total precipitation, and annual maximum snow depth) were obtained from an existing spatial data set. Relationships between ANPP and environmental factors were analyzed by regression tree models. For the tree model with ANPP as a dependent variable, four environmental factors (annual mean temperature, wetness index, openness, topographic radiation index) were adopted as independent variables. Annual mean temperature was the first split variable in this model and explained 25.5% of the total deviance in ANPP. Wetness index, which represents soil moisture variation caused by lateral flow, explained 11.5% of the total deviance in ANPP. The resulting tree model explained approximately half of the total deviation in ANPP and indicated that the spatial distribution of Japanese cedar productivity was controlled by regional-scale interactions between climatic and topographic processes. A high-resolution map of productivity was prepared by use of the ANPP prediction model and vegetation information obtained from satellite data.  相似文献   
30.
Congenital vitelline duct anomalies other than Meckel’s diverticulum are rare in animals. A cyst of approximately 8 mm in diameter was observed on the antimesenteric surface of the ileal serosa in a 10-week-old female Crl:CD(SD) rat. Microscopically, the cyst closely resembled the ileum, but it did not communicate with the ileal lumen. We diagnosed this case as a vitelline cyst derived from the vitelline duct based on the location where it developed and its histological behavior. In rats, only Meckel’s diverticulum has been reported with a congenital anomaly of the vitelline duct, and no other spontaneous anomalies including a vitelline cyst have been reported. This case may be the first report concerning a vitelline cyst in the rat ileum.  相似文献   
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