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Dragonfly and damselfly (Odonata) species were surveyed from May to October 2002 on 38 small irrigation ponds in the north part of Awaji Island. The investigation was conducted nine times on each pond. Totally 1568 individuals of 28 species were recorded for six months. We selected nine species recorded more than 40 individuals and analyzed the relationships of individual number of these species with environmental factors, including conductivity, NO2-, NO3-, NH4-, PO43-, COD, surrounding land uses within 50 meters from the edge of pond, the number of aquatic water plant species, and autocovariates explaining spatial autocorrelation, using Generalized Linear Models (GLM). The result showed that NO3-, COD, surrounding grassland, woodland and the number of water plant species were critical factors for the distribution of some Odonata species.

To characterize the “portal signal” in a nonsteady hyperglycemic state, the kinetic relationship between net hepatic glucose balance (NHGB) and either hepatic glucose load (HGL) or plasma insulin level was determined during glucose infusion using a catheter technique in 36 conscious dogs. Glucose was infused intraportally (Po group) and peripherally (Pe group) at 39, 56, and 83 μmol · kg−1 · min−1over 2 h. There was a linear relationship between mean NHGB and either mean HGL or plasma insulin levels at each rate in either delivery (HGL: Po r = 0.99, Pe r = 0.95; insulin: Po r = 99, Pe r = 0.79). The threshold levels for net hepatic glucose uptake were 3.8 and 11.7 mmol/l for plasma glucose and 65 and 392 pmol/l for plasma insulin, respectively. The slope of the regression line against the abscissa was four times larger in portal than in peripheral delivery (HGL: Po 0.20 vs. Pe 0.05, P < 0.05; insulin: Po 0.19 vs. Pe 0.04, P < 0.05). These results suggest that the portal signal overrules the threshold of glucose for hepatic uptake by increasing hepatic extraction rate in a nonsteady hyperglycemic state.