• 한국노년학
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• v.37 no.1
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• pp.201-219
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• 2017

This study was performed to test the socioemotional selectivity theory (SST) with Korean adults. According to SST, perceiving their life as limited, people are motivated to enhance their mood by regulating their mood in such a way to maximize the positive emotions and weaken the negative ones. Being founded on the dialectical constructs which assume the positive and negative sides of emotional experience coexist, Korean adults were supposed to be less motivated to maximize positive emotions and weaken negative emotions. Thus the elderly koreans might regulate emotions not in the direction of maximizing the positive emotions and weakening the negative ones, but in the direction of not being highly aroused. 166 youth, middle-aged, and elderly were asked to rate the frequencies of 31 positive and negative emotions they had experienced during the last month. In addition, they were asked to judge whether they weaken / adapt / maximize their emotions after experiencing positive and negative events. The elderly experienced less positive emotions as well as negative emotions than youth. Youth experienced emotions of high arousal more often than those of low arousal, but the elderly experienced emotions of high arousal less often. The responses of weakening their negative emotions and their positive emotions were largest in the elderly group. On the other hand, the response of maximizing their positive emotions were largest in the youth group. These results show that the elderly maintains emotional stability by weakening both positive and negative emotions of high arousal.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.390-395
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• 2004

In order to characterize ion channels present in tomato roots, microsomes were incorporated into an artificial lipid bilayer arranged for electrophysiological analysis. Of the five different ion channels that could be found, a channel of 450 pS conductance was found most frequently. This channel displayed subconductance states of 450, 257 and 105 pS. All subconductance states showed linear current-voltage relationships. At positive holding potentials, high frequency of transient channel openings was observed; however, at negative potentials, the open times were long and open probability high. Po was 0.83 at -40 mV. When an additional 50 mM $K^+\;or\;Na^+$ was added to the cis side of bilayer, the reversal potentials shifted in the negative direction to near -10 mV. Thus, the 450 pS cation channel selects poorly between $K^+\;and\;Na^+$. In the presence of $100\;{\mu}M$ metal ions, the channel activity was severely inhibited by $La^{3+},\;Ba^{2+},\;and\;Zn^{2+}$, and Po was decreased to 0.2 or even less. However, $Al^{3+}\;and\;Cd^{2+}$ decreased the activity by only 20%. Interestingly, each metal ion showed different kinetics of channel inhibition. While $500\;{\mu}M\;La^{3+}$ inhibited the activities of all subconductance state, 1 mM $Zn^{2+}$ inhibited all except the 105 pS state. $Cd^{2+}$ changed the gating of the channel from a long-opening state to brief transient openings even at negative holding potentials. These data represent that the metal ions may have different binding sites on the channel protein and could be useful modulators and probes to investigate structural characteristics as well as the functional roles of the 450 pS channel on the root physiology.