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Due to the fact that the flood data series of small drainage basins is relatively short, available data are often not sufficient for flood risk analysis. This presents the problem of risk analysis using very small data samples. One method that can be applied is to regard the available small samples as fuzzy information and optimize them using information diffusion technology to yield analytical results with greater reliability. In this article a risk analysis method based on information diffusion theory is applied to create a new flood risk analysis model. Application of the model is illustrated taking the Jinhuajiang and Qujiang drainage basins as examples. This is a new attempt at applying information diffusion theory in flood risk analysis. Computations based on this analytical flood risk model can yield an estimated flood damage value that is relatively accurate. This study indicates that the aforementioned model exhibits fairly stable analytical results, even when using a small set of sample data. The results also indicate that information diffusion technology is highly capable of extracting useful information and therefore improves system recognition accuracy. This method can be easily applied and the analytical results produced are easy to understand. Results are accurate enough to act as a guide in disaster situations.  相似文献   
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Abstract In the field, adult males of the grasshopper Phymateus morbillosus are able to fly for up to 1 min and cover up to c. 100 m, whereas females, although fully winged, are apparently unable to get airborne. Morphometric data indicate that the males are lighter, have longer wings, a higher ratio of flight muscles to body mass, and a lower wing load value than females. It was investigated whether this inability of females to fly is related to fuel storage, flight muscle enzymatic design and/or the presence and quantitative capacity of the endocrine system to mobilize fuels. In both sexes, readily available potential energy substrates are present in the haemolymph in similar concentrations, and the amount of glycogen in flight muscles and fat bodies does not differ significantly between males and females. Mass-specific activities of the enzymes GAPDH (glycolysis), HOAD (fatty acid oxidation) and MDH (citric acid cycle) in flight muscles are significantly lower in females compared with males, and mitochondria are less abundant in the flight muscles of females. There is no significant difference between the ability of the two sexes to oxidize various important substrates. Both sexes contain three adipokinetic peptides in their corpora cardiaca; the amount of each peptide in female grasshoppers is higher than in males.
Thus, despite some differences listed above, both sexes appear to have sufficient substrates and the necessary endocrine complement to engage in flight. It seems more likely, from the morphometric data above, that the chief reason for flightlessness is that P. morbillosus females cannot produce sufficient lift for flight; alternatively, the neuronal functioning associated with the flight muscles may be impaired in females.  相似文献   
4.
We isolated a Zea mays cDNA encoding the 40S subunit cytoplasmic ribosomal protein S11. The nucleotide sequence was determined and the derived amino acid sequence compared to the corresponding Arabidopsis thaliana protein showing an homology of 90%. This ribosomal protein is encoded by a small multigene family of at least two members. The mRNA steady-state level is about one order of magnitude higher in rapidly growing parts of the plant such as the roots and shoots of seedlings compared to fully expanded leaf tissue.  相似文献   
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The effects of invasive macrophytes, water level fluctuations and predation on freshwater unionids Pyganodon grandis and Utterbackia imbecillis were studied in three small impoundments in Northeastern Texas in 2003–2005. Mussel density was sampled with quadrats. Mortality, associated with the water level fluctuations and predation, was estimated by collecting dead shells on the shore at about two month intervals. In two ponds, horizontal distribution of unionids was limited by dense beds of invasive and noxious macrophytes (mainly Eurasian watermilfoil Myriophyllum spicatum and American lotus Nelumbo lutea): mussel densities were significantly lower in these macrophyte beds (P < 0.001). In the third pond with the lowest density of macrophytes (stonewort Chara sp.), unionids were distributed more evenly, and the average unionid biomass was the highest among all ponds studied. Vertical distribution of unionids in all ponds was likely limited by low oxygen at depth >2 m. The total amount of shells found on the shore per year varied from 0.1% to 28% of the total population in the pond and was negatively correlated with water level (r = −0.72 to −0.81, P < 0.005). Mammalian predators consumed up to 19% of the total unionid population and predation was facilitated by water level fluctuations. Handling editor: K. Martens  相似文献   
7.
Electrophysiological studies of cultured rat pancreatic β-cells using intracellular microelectrodes show that exogenous insulin over the range of 0.1–10.0 μg/ml inhibits the electrical activity due to 27.8 mM glucose in a dose-related manner. This inhibitory effect is manifested by a mean increase of the membrane potential from about ?20 to ?30 mV and inhibition of the manner of cells impaled showing spike activity from 60 to less than 10%. The inhibitory influence of insulin is rapid occuring within 5 min for the highest level used. The results provide evidence for a negative feedback role of insulin in regulating its own release.  相似文献   
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HOMMEL  G. 《Biometrika》1988,75(2):383-386
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The haematology and phospholipase activity and mast cell numbers of the small intestine and colon of rats was studied 10 days after infection with various numbers of larvae of N. brasiliensis. A significant reduction in the RBC occurred after infections with 200 and 5000 larvae but not with 1000 larvae. Hb was significantly reduced after infection with 200 larvae and increases in the MCV and MCH indicated the development of a macrocytic anaemia. Reticulocyte count was increased at all levels of infection except after 200 larvae. WBC was increased at all levels of infection except in the 5000 larvae group. Lymphocytes were significantly increased in all groups except those infected with 5000 larvae. Neutrophils increased only at the lower levels of infection. The most marked changes occurred in eosinophil numbers, significant increases occurring with increasing levels of infection. However, after infection with 5000 larvae the numbers were significantly lower than after infection with 200 or 1000 larvae. Phospholipase activity, which is believed to be related to tissue eosinophil levels, was significantly increased at all infection levels in the proximal small intestine. Significant increases in the distal ileum and colon occurred mainly after infection with 1000 and 5000 larvae. Mast cell numbers did not change significantly at any infection level. It is suggested that the pathology observed, here in the form of anaemia, is multifactorial in origin and is largely a function of the immune response, the development and expression of which is dependent on the level of infection, with suppression of immune damage occurring at the high levels of infection when pathogenesis may involve a direct effect of the worms.  相似文献   
10.
In intact, uncoupled type B chloroplasts from spinach, added ATP causes a slow light-induced decline (t12 ≈ 3 min) of chlorophyll a fluorescence at room temperature. Fluorescence spectra were recorded after fast cooling to 77 K and normalized with fluorescein as an internal standard. Related to the fluorescence quenching at room temperature, an increase in Photosystem (PS) I fluorescence (F735) and a decrease in PS II fluorescence (F695) were observed in the low-temperature spectra. The change in the F735F695 ratio was abolished by the presence of methyl viologen. Fluorescence induction at 77 K of chloroplasts frozen in the quenched state showed lowered variable (Fv) and initial (F0) fluorescence at 690 nm and an increase in F0 at 735 nm. The results are interpreted as indicating an ATP-dependent change of the initial distribution of excitation energy in favor of PS I, which is controlled by the redox state of the electron-transport chain and, according to current theories, is caused by phosphorylation of the light-harvesting complex.  相似文献   
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