• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.43-53
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• 1987

In order to improve effectiveness of rhizobia- legume symbiotic nitrogen fixation, ecological and physiological characteristics of indigenous rhizobia distributed in Korea, that is, symbiotic effectiveness of indigenous soybean rhizobia, nitrate reductase activities of the soybean bacteroid from five different soils, and differences of host-infection abilities among the soybean cultivars under population densities of the same indigenous soybean rhizobia, were investigated. The results were summarized as follows: 1. The number of indigenous soybean rhizobia was ranged from $9.2{\times}10^2$ cells per gram of soil in calcareous soil II to $42.4{\times}10^3$ cells per gram of soil in calcareous soil I in Danyang. 2. The symbiotic effectiveness of indigenous soybean rhizobia from five different soils was high in the case of soybean continuously cultivated, and calcareous soil I that population densities of indigenous soybean rhizobia were observed highly. 3. Inverse relationship was observed between total nitrogenase activity (TNA) and nitrate reductase activity (NRA) from the soybean bacteroids ($r=-0.502^*$), but the correlation between nitrate reductase and specific nitrogenase activities (SNA) could be devided into two groups. It was classified into group I which is high in SNA and low in NRA, and group II which is low in SNA and high in NRA. 4. The infection ability of the indigenous soybean rhizobia in the same soil conditions showed the reciprocal difference among each soybean cultivars. In Kwangkyo and Jangyeup, the symbiotic effectiveness appeared by infection of indigenous soybean rhizobia was higher than it of the other soybean cultivars.

• The Journal of the Petrological Society of Korea
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• v.11 no.3_4
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• pp.200-213
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• 2002

The Andong granitoid batholith represents five temporally distinct episodes (phases) of igneous activity. The batholith represents a plutonic complex of five pulsatively emplaced distinct intrusive multiphases. The petrochemical data show that the plutons fall into calc-alkaline series except for the Yean pluton, and plot within the diaenostic range for I-type origin and continental arc orogenic tectonic setting. Each pluton reveals systematic compositional variations of major and trace elements with $SiO_2$ or MgO, but different variation trends for some elements and considerably different REE patterns. Thus discontinuous, inconsistent variations in the elements indicate that the five plutons can not be explained by simple fractional crystallization from the same primary magma, but were intruded and solidified from the independent magmas of chemically heterogeneous origin. In the Andong, Dosan and Pungsan plutons, high values of molar CaO/(MgO+$FeO^{t}$ ) combined with low $Al_2$$O_3$/(MgO+$FeO^{t}$ ) and $K_2$O$Na_2$O ratios suggest a magma originated by dehydration melting of a metabasaltic to metatonalitic protolith. Whereas the Imha pluton show similar values of CaO/(MgO+$FeO^{t}$ ), but significantly higher ratios of $Al_2$$O_3$/(MgO+$FeO^{t}$ ) and $K_2$O$Na_2$O implying to a metagreywacke protolith.

• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.24-36
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• 2002

Background: Bronchial reactivity is known to be a component of airway hyperresponsiveness, a cardinal feature of asthma, with bronchial sensitivity, and is increments in response to induced doses of bronchoconstrictors as manifested by the steepest slope of the dose-response curve. However, there is some controversy regarding methods of measuring bronchial reactivity and clinical impact of such measurements. The purpose of this study was to evaluate the clinical significance and assess the clinical use by analyzing the relationship of the bronchial sensitivity, the clinical severity and the changes in pulmonary function with bronchial reactivity. Method: A total of 116 subjects underwent a methacholine bronchial provocation test. They were divided into 3 groups : mild intermittent, mild persistent, moderate and cough asthma. Severe patients were excluded. Methacholine PC20 was determined from the log dose-response curve and PC40 was determined by one more dose inhalation after PC20. The steepest slope of log dose-response curve, connecting PC20 with PC40, was used to calculate the bronchial reactivity. Body plethysmography and a single breath for the DLCO were done in 43 subjects before and after methacholine test. Results: The average bronchial reactivity was 38.0 in the mild intermittent group, 49.8 in the mild persistent group, 61.0 in the moderate group, and 41.1 in the cough asthma group. There was a weak negative correlation between PC20 and bronchial reactivity. A heightened bronchial reactivity tends to produce an increased clinical severity in patients with a similar bronchial sensitivity and basal spirometric pulmonary function. There were significant correlations between the bronchial reactivity and the initial pulmonary function before the methacholine test in the order of sGaw, Raw, $FEV_1$/FVC, MMFR. There were no correlations between the bronchial sensitivity and the % change in the pulmonary function parameters after the methacholine test. However, there were significant correlations between the bronchial reactivity and the PEF, $FEV_1$, DLCO. Conclusion: There was weak significant negative correlation between the bronchial reactivity and the bronchial sensitivity, and the bronchial reactivity closely reflected the severity of the asthma. Accordingly, measuring both the bronchial sensitivity and the bronchial reactivity can be of assistance in assessing of the ongoing disease severity and in monitoring the effect of therapy.