• Economic and Environmental Geology
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• v.26 no.2
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• pp.193-206
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• 1993

A total of 111 independently oriented core samples were drilled at 12 sites in fue Kimpo area ($37.70^{\circ}N$, $126.55^{\circ}E$) of the Taedong Supergroup. The Taedong strata are composed of sandstone, conglomeratic sandstone, shale and thin coal seams. The age of the strata is known to be Late Triassic-Early Jurassic according to freshwater Esfuerites and plant fossil (Dictyophyllum-Clathropteris flora) contents. Through AF and thermal demagnetization, an area-mean ChRM direction of $D=48.3^{\circ}\;I=40.3^{\circ}\;{\alpha}_{95}=7.9^{\circ}\;k=59.5$, n=7 was obtained. It passed fold and reversal test in the formation-mean level. Fold test was not significant in the area-mean level. The palaeomagnetic north pole calculated from the area-mean lies at $46.3^{\circ}N$, $222.0^{\circ}E$ with dp=5.7, $dm=9.5^{\circ}$. This pole position is very similar to those of the South China Block (SCB) in Triassic times. Palaeolatitude of the Kimpo area in the Taedong times was $23.0^{\circ}N$, again very similar to the palaeolatitude of the South China Block in the Late Triassic. This low latitude of the study area at the time of deposition explains the tropical-subtropical nature of fossil contents of the Taedong Supergroup.

• Journal of the Korean Magnetics Society
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• v.18 no.1
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• pp.28-31
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• 2008

We studied the effect of easy magnetization axis orientation with respect to the strip direction by measuring the magnetoresistance(MR), the magneto-optic Kerr effect(MOKE), and real-time domain evolution. The five strips were patterned on a single chip with the easy axis orientation of each strip relative to the longitudinal direction by around $0^{\circ}$, $18^{\circ}$, $36^{\circ}$, $54^{\circ}$ and $72^{\circ}$, respectively. The overall shape of field dependent MR was mostly governed by the anisotropy magnetoresistnace. The relative change of the longitudinal MR was significantly increased with increasing angle between the easy axis and strip direction, whereas, the transverse MR variation rate was decreased with increasing angle. Several MR steps were observed during the magnetization reversal, and the simultaneous measurement of the MOKE and the domain images identified that the MR steps were associated with evolution of the oppositely directed magnetic domain.

• Lingua Humanitatis
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• v.1 no.2
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• pp.161-178
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• 2001

This study investigates how Korean traditional family consciousness interacts with Korean industrialization in the 1970s. In Our Children, Lee Sun depicts a family's struggle within the turmoil brought about by rapid industrialization to escape from the ranks of the working class. It is well known that one of the consequences of industrialization was the breakup of the larger family structure into nuclear families, but Lee Sun presents Korea's industrialization in the 1970s in the light of the traditional Korean family culture before the breakup. In other words, he gives us a portrayal of Gemeinschaft in Gesellschaft in his description of the extended family's struggle to overcome the day-to-day pressures of modernization and urbanization. The novel presents three generations of a traditional extended family. The eldest son is portrayed as a knife, strong and sharp. His wife has a temporary job that she hopes to give up once they own a house, which symbolizes the family's escape from the working class. The relationship among the family members reveals the core aspects of the ideology governing traditional extended families: the husband is the despotic monarch of the household, solely responsible for the family's economy; the husband is the sky and the wife the earth; and children (the more the better) are expected to lead to stability, welfare, and prosperity. One curious aspect of this family relationship as portrayed by Lee Sun is the expectation that being the eldest son, who already is or will become the patriarch of the family, is the fastest way of reaching middle-class status. And, despite a slight reversal, the novel has a happy ending wherein the family's expectations are fulfilled without much suffering. This aspect should be considered in light of the revolutionary romantic idealism of the novels of the 1930s. The lack of suffering and the easy happy ending may be attributed to the fact that Korea's industrialization came about rapidly and radically, and therefore it is likely that Lee Sun was not able fully to appreciate the full costs of industrialization. This limitation calls for a deeper investigation into the social structure and class consciousness of the 1970s, and also a study of the intertextual relationship of Our Children with other novels of the time.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.5
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• pp.525-531
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• 2016

The analgesic mechanism of opioids is known to decrease the excitability of substantia gelatinosa (SG) neurons receiving the synaptic inputs from primary nociceptive afferent fiber by increasing inwardly rectifying $K^+$ current. In this study, we examined whether a ${\mu}$-opioid agonist, [D-Ala2,N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO), affects the two-pore domain $K^+$ channel (K2P) current in rat SG neurons using a slice whole-cell patch clamp technique. Also we confirmed which subtypes of K2P channels were associated with DAMGO-induced currents, measuring the expression of K2P channel in whole spinal cord and SG region. DAMGO caused a robust hyperpolarization and outward current in the SG neurons, which developed almost instantaneously and did not show any time-dependent inactivation. Half of the SG neurons exhibited a linear I~V relationship of the DAMGO-induced current, whereas rest of the neurons displayed inward rectification. In SG neurons with a linear I~V relationship of DAMGO-induced current, the reversal potential was close to the $K^+$ equilibrium potentials. The mRNA expression of TWIK (tandem of pore domains in a weak inwardly rectifying $K^+$ channel) related acid-sensitive $K^+$ channel (TASK) 1 and 3 was found in the SG region and a low pH (6.4) significantly blocked the DAMGO-induced $K^+$ current. Taken together, the DAMGO-induced hyperpolarization at resting membrane potential and subsequent decrease in excitability of SG neurons can be carried by the two-pore domain $K^+$ channel (TASK1 and 3) in addition to inwardly rectifying $K^+$ channel.

• Archives of Pharmacal Research
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• v.29 no.4
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• pp.310-317
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• 2006

We investigated the effects of trinitrobenzene sulfonic acid (TNBS), an amino-group reagent, on the human ether-a-go-go-related gene (HERG) $K^+$ channels expressed in Xenopus oocytes. TNBS neutralizes the positively charged amino-groups of peptide N-terminal and lysine residues. External application of TNBS at 10 mM for 5 min irreversibly shifted the curves for currents at the end of the pulse and tail currents of HERG to a more negative potential and decreased the maximal amplitude of the $I_{tail}$ curve $(I_{tail,max})$. TNBS had little effect on either the activated current-voltage relationship or the reversal potential of HERG current, indicating that TNBS did not change ion selectivity properties. TNBS shifted the time constant curves of both activation and deactivation of the HERG current to a more hyperpolarized potential; TNBS's effect was greater on channel opening than channel closing. External $H^+$ is known to inhibit HERG current by shifting $V_{1/2}$ to the right and decreasing $I_{tail,max}$. TNBS enhanced the blockade of external $H^+$ by exaggerating the effect of $H^+$ on $I_{tail,max}$, not on $V_{1/2}$. Our data provide evidence for the presence of essential amino-groups that are associated with the normal functioning of the HERG channel and evidence that these groups modify the blocking effect of external $H^+$ on the current.

• Cross-Cultural Studies
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• v.27
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• pp.167-195
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• 2012

A Chinese female writer Linhaiyin(林海音) and Chengnanjiushi(城南舊事), her representative work, have never been studied in Korea before although she and her literary works stand high and are well known in the history of the modern Chinese literature. Thus, in this paper, I analyze her and her novels included in Chengnanjiushi and study their literary value and meaning. To analyze and study them, I mainly consider novels Anhuiguan, Womenkanhaiqu, Lanyiniang, $L{\acute{\ddot{u}}}dagunr$, and Babadehuarluole included in Chengnanjiushi. Firstly, I look into her attitude and mode to observe children and women's life as a writer. Such attitude and mode succeeded to the spirit of the '5.4 literature'. Secondly, I evaluate Linhaiyin's 'Both sides complex' and its value in the history of literature. From this evaluation, the meaning of Linhaiyin's literature is highlighted. She was free from 'Both sides complex' occurred due to the circumstance of the times and played a role of a bridge so as not to break off literature of China and Taiwan. When her and her works are evaluated, this is one of the most important values. The characteristic of her writing mode is that she did not seek a compelling climax, a surprising reversal, or an exclusive plot or character in her works. In her works, plain description or unwitting conversation and story often imply deep meanings. Thus, at unexpected moment after reading her novels, readers truly listen to deep resonance for her attitude and mode to observe people's life. This is exactly her potential energy that makes readers sink into her literary world regardless of time and space.

• Atmosphere
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• v.28 no.4
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• pp.403-414
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• 2018

Predictability of Northern Hemisphere blocking in the Korea Meteorological Administration (KMA) Global Data Assimilation and Prediction System (GDAPS) is evaluated for the period of July 2016 to May 2017. Using the operational model output, blocking is defined by a meridional gradient reversal of 500-hPa geopotential height as Tibaldi-Molteni Index. Its predictability is quantified by computing the critical success index and bias score against ERA-Interim data. It turns out that Northwest Pacific blockings, among others, are reasonably well predicted with a forecast lead time of 2~3 days. The highest prediction skill is found in spring with 3.5 lead days, whereas the lowest prediction skill is observed in autumn with 2.25 lead days. Although further analyses are needed with longer dataset, this result suggests that Northern Hemisphere blocking is not well predicted in the operational weather prediction model beyond a short-term weather prediction limit. In the spring, summer, and autumn periods, there was a tendency to overestimate the Western North Pacific blocking.

• Journal of Astronomy and Space Sciences
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• v.36 no.3
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• pp.159-168
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• 2019

In solstices during the solar minimum, the hemispheric difference of the equatorial ionization anomaly (EIA) intensity (hereafter hemispheric asymmetry) is understood as being opposite in the morning and afternoon. This phenomenon is explained by the temporal variation of the combined effects of the fountain process and interhemispheric wind. However, the mechanism applied to the observations during the solar minimum has not yet been validated with observations made during other periods of the solar cycle. We investigate the variability of the hemispheric asymmetry with local time (LT), altitude, season, and solar cycle using the electron density taken by the CHAllenging Minisatellite Payload satellite and the global total electron content (TEC) maps acquired during 2001-2008. The electron density profiles provided by the Constellation Observing System for Meteorology, Ionosphere, and Climate satellites during 2007-2008 are also used to investigate the variation of the hemispheric asymmetry with altitude during the solar minimum. During the solar minimum, the location of a stronger EIA moves from the winter hemisphere to the summer hemisphere around 1200-1400 LT. The reversal of the hemispheric asymmetry is more clearly visible in the F-peak density than in TEC or in topside plasma density. During the solar maximum, the EIA in the winter hemisphere is stronger than that in the summer hemisphere in both the morning and afternoon. When the location of a stronger EIA in the afternoon is viewed as a function of the year, the transition from the winter hemisphere to the summer hemisphere occurs near 2004 (yearly average F10.7 index = 106). We discuss the mechanisms that cause the variation of the hemispheric asymmetry with LT and solar cycle.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.1
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• pp.49-59
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• 2021

Background: To evaluate changes in the effectiveness of phentolamine mesylate in combination with different local anesthetics (LAs) and vasoconstrictors. A prospective randomized double-blind study was conducted with 90 patients divided into three groups, with each group being administered one of three different LAs: lidocaine 2% 1/80,000, articaine 4% 1/200,000, and bupivacaine 0.5% 1/200,000. Methods: We compared treatments administered to the mandible involving a LA blockade of the inferior alveolar nerve. Results were assessed by evaluating reduction in total duration of anesthesia, self-reported patient comfort using the visual analog pain scale, incidence rates of the most common adverse effects, overall patient satisfaction, and patient feedback. Results: The differences among the three groups were highly significant (P < 0.001); time under anesthesia was especially reduced for both the lip and tongue with bupivacaine. The following adverse effects were reported: pain at the site of the anesthetic injection (11.1%), headaches (6.7%), tachycardia (1.1%), and heavy bleeding after treatment (3.3%). The patients' feedback and satisfaction ratings were 100% and 98.9%, respectively. Conclusions: Efficient reversal of LAs is useful in dentistry as it allows patients to return to normal life more readily and avoid common self-injuries sometimes caused by anesthesia. Phentolamine mesylate reduced the duration of anesthesia in the three studied groups, with the highest reduction reported in the bupivacaine group (from 460 min to 230 min for the lip and 270 min for the tongue [P < 0.001]).

• Atmosphere
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• v.33 no.1
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• pp.49-59
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• 2023

Blocking refers to a class of weather phenomena appearing in the mid and high latitudes, whose characteristics are blocked airflow of persistence. Frequently found over the Pacific and Atlantic regions of the Northern Hemisphere, blocking affects severe weather in the surrounding areas with different mechanisms depending on the type of blocking patterns. Along with lots of studies about persistent weather extremes focusing on the specific types of blocking, a new categorization using Rossby wave breaking has emerged. This study aims to apply this concept to the classification of blockings over the Pacific and examine how different wave breakings specify the associated cold weather in the Korean peninsula. At the same time, we investigate a strongly developing ridge around the Pacific by designing a new detection algorithm, where a reversal method is modified to distinguish ridge-type blocking patterns. As result, Kamchatka blocking (KB) and strong ridge over the Central Pacific are observed the most frequently during 20 years (2001~2020) of the studied period, and anomalous low pressures with cold air over the Korean Peninsula are accompanied by blocking events. When it considers the Rossby wave breaking, cyclonic wave-breaking is dominant in KB, which generates low-pressure anomalies over the Korean Peninsula. However, KB with anticyclone wave breaking appears with the high-pressure anomalies over the Korean Peninsula and it generates the warm temperature anomaly. Lastly, the low-pressure anomalies are also generated by the strong ridge over the Central Pacific, which persists for approximately three days and give a significant impact on cold surge on the Korean Peninsula.