• Restorative Dentistry and Endodontics
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• v.26 no.4
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• pp.307-315
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• 2001

The application of Nd:YAG laser and irrigants to the root surface can change its surface configurations. The purpose of this study was to investigate the effects of Nd:YAG laser and irrigants on the apical seal of obturated canals. In this study, 66 single rooted teeth were randomly assigned to 4 group of 14 teeth each. 8 teeth were served us positive and negative controls. The teeth were divided into 6 groups as follows. Group A: Nd:YAG laser, 5% NaOCl + Rc-prep Group B: Nd:YAG laser, Saline Group C: 5% NaOCl + Rc-prep Group D: Saline Group E: Positive control Group F: Negative control 66 teeth were instrumented using Maillefer ProFile$^{\circledR}$ (Orifice Shapers, .04 taper, .06 taper Dentsply, Switzerland). Two of each group were selected at random, and the canal wall surfaces were examined under a SEM. 12 teeth of each group were obturated using by lateral condensation technique. Specimens were immersed in india ink for 7days, decalcified by 10% nitric acid, dehydrated by 75. 80. 85, 90, 95 and 100% alcohol in order cleared by methyl salicylate and then measured of dye penetration with stereomicroscope($\times$15 magnification) and Image Pro plus. The data were analyzed statistically by one-way ANOVA test and Duncan's Multiple Range test. The results were as follows : 1. The mean leakage was 0.128$\pm$0.376 for group A, 0.237$\pm$0.325 for group B, 0.397$\pm$0.468 for group C, 0.586$\pm$0.402 for group D, and there were statistically significant differences between group A and group D, group B and group D. (p<0.05). 2. Group A had better sealing ability than Group C, but there was statistically no significant differences. (p>0.05). 3. Group B had better sealing ability than Group D and there was statistically significant difference. (p<0.05). 4 Group A had better sealing ability than Group B, but there was statistically no significant difference. (p>0.05). 5. Group C had better sealing ability than Group D, but there was statistically no significant difference. (p>0.05). 6. As a result of observation under SEM, Smear layers were removed in Group A, B. but Smear layers were partially removed and smear plugs were remained in Group C, Smear layers were not removed in Group D. To be specially, Melting of smear layer were showed in Group C. 7. These results suggests that the laser has a potential in reducing the apical microleakage of obturated canals.

• Korean Journal of Legislative Studies
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• v.24 no.1
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• pp.135-170
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• 2018

The recent success of populist parties and candidates in the US and European countries leads to a massive amount of empirical research on populism, a deviant form of representative democracy. Much ink has been spilled to define populism and to identify the causes of its rise and continued success in democratic political system. However, little is known about populist attitudes of individual voters. Using a large-scale online survey fielded in the context of the South Korean presidential election in 2017, this study examines (1) what determines populist attitudes of South Korean voters and (2) how populist attitudes are associated with evaluations of political parties, candidates, and political issues. Statistical analysis reveals that people high on populism are more likely to support an underdog left-wing political party and its presidential candidate, and are less likely to support policies implemented or proposed under the auspices of the Park Geun-hye administration. These findings do not necessarily suggest the inherent affinity between populism and left-wing ideology; rather, it implies populist attitudes happened to appear in 2017, in reactions to lack of confidence in the previous government.

• Journal of Veterinary Science
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• v.21 no.2
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• pp.26.1-26.14
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• 2020

Pancreatic ductal adenocarcinoma is a lethal cancer type that is associated with multiple gene mutations in somatic cells. Genetically engineered mouse is hardly applicable for developing a pancreatic cancer model, and the xenograft model poses a limitation in the reflection of early stage pancreatic cancer. Thus, in vivo somatic cell gene engineering with clustered regularly interspaced short palindromic repeats is drawing increasing attention for generating an animal model of pancreatic cancer. In this study, we selected Kras, Trp53, Ink4a, Smad4, and Brca2 as target genes, and applied Campylobacter jejuni Cas9 (CjCas9) and Streptococcus pyogens Cas9 (SpCas9) for developing pancreatic cancer using adeno associated virus (AAV) transduction. After confirming multifocal and diffuse transduction of AAV2, we generated SpCas9 overexpression mice, which exhibited high double-strand DNA breakage (DSB) in target genes and pancreatic intraepithelial neoplasia (PanIN) lesions with two AAV transductions; however, wild-type (WT) mice with three AAV transductions did not develop PanIN. Furthermore, small-sized Cjcas9 was applied to WT mice with two AAV system, which, in addition, developed high extensive DSB and PanIN lesions. Histological changes and expression of cancer markers such as Ki67, cytokeratin, Mucin5a, alpha smooth muscle actin in duct and islet cells were observed. In addition, the study revealed several findings such as 1) multiple DSB potential of AAV-CjCas9, 2) peri-ductal lymphocyte infiltration, 3) multi-focal cancer marker expression, and 4) requirement of > 12 months for initiation of PanIN in AAV mediated targeting. In this study, we present a useful tool for in vivo cancer modeling that would be applicable for other disease models as well.

• MISULJARYO - National Museum of Korea Art Journal
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• v.98
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• pp.176-199
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• 2020

In 2018, the National Museum of Korea purchased a pair of Japanese folding screens, respectively entitled Gathering on the Year's First "Day of the Rat" and Boating on the Oi River. Both of these two screens (hereinafter collectively referred to as the "NMK edition") have a gold background that bears the seal and ink inscription of Tosa Mitsuyoshi (1700-1772), who served as edokoro azukari, a painter in the court of Kyoto. According to the seller in New York, the screens were brought from Japan to the United States in the early twentieth century, but no other details are known. Each folding screen has six panels. The screen on the right (i.e., Gathering…) depicts "nenohi no asobi," an annual event conducted on the first "day of the rat" (according to the Asian zodiacal calendar), wherein the Kyoto imperial court ventured to the woods to gather pine seedlings. The left screen (i.e., Boating…) shows three boats traveling down the Oi River in Kyoto, representing the ritual known as "mifune" (literally, "three boats"), which involves three boats representing Chinese classical poetry (kansi), Japanese classical poetry (waka), and Japanese imperial music and dance (gagaku). Notably, these two screens are identical in theme and iconography to two screens with the same respective titles that were commissioned by Emperor Komei (1831-1867) and painted by Ukita Ikkei (1795-1859), an artist of the Yamato-e Revivalist School (fukko yamato-e), now in the collection of Sennyu-ji Temple in Kyoto (hereinafter collectively referred to as the "Sennyu edition"). While both of these themes have been painted independently numerous times, the NMK edition and Sennyu edition are the only known cases of the themes being painted as a single set. According to Diary of Official Business Between the Court and Shogunate (the journal of a court official named Hirohashi Kanetane, 1715-1781), Tosa Mitsuyoshi was commissioned in 1760 to replace the fusuma (rectangular sliding panels) of Tsunegoten, one of the buildings of the Kyoto Imperial Palace, which had been built in 1709. Notably, records show that Tsunegoten once contained a series of fusuma painted by an artist of the Kano school on the themes "Outdoor Procession on a Spring Day" and "Three Boats Cruising on the Oi River." Hence, it seems probable that Tosa Mitsuyoshi was influenced by the theme and iconography of the existing fusuma in producing his own folding screens depicting the court's visit to the forest and a cruise on the Oi River. While the practice of collecting pine seedlings on the first "rat day" of the year was an auspicious event to pray for longevity, the mifune ritual was intended to honor the greatest talents of the three aforementioned arts, which were of crucial importance to the court of Kyoto. Folding screens with such auspicious themes were commonly featured at the ceremony to enthrone the emperor or empress. Significantly, the Diary of Official Business Between the Court and Shogunate also records that Tosa Mitsuyoshi, while working as a court artist, produced two pairs of folding screens for the coronation of Empress Go Sakuramachi (1762-1771), which was held in 1763. Hence, research suggests that the NMK edition is one of the pairs of royal folding screens produced at that time.

• Korean Journal of Heritage: History & Science
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• v.52 no.2
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• pp.172-195
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• 2019

Among the paintings of Goam Lee Ungno (1904-1989), his works of the 1960s in Paris have been evaluated as his most avant-garde works of experimenting with and innovating objects as an artist. At that time, his works, such as Papier Colle and Abstract Letter, were influenced by abstract expressionism and Western Art Informel, illustrating his transformation from a traditional artist into a contemporary artist. An exhibition, which was held prior to his going to Paris in March 1958, has received attention because it exhibited the painting style of his early Informel art. Taking this into consideration, this study was conducted by interpreting his work from two perspectives; first, that his works of 1958 were influenced by abstract expressionism and Art Informel, and, second, that he expressed Xieyi (寫意) as literati painting, focusing on the fact that Lee Ungno first started his career adopting this style. In this paper, I aimed to confirm Lee Ungno's recognition of Art Informel and abstract painting, which can be called abstract expressionism. To achieve this, it was necessary to study Lee's painting theory at that time, so I first considered Hae-gang Kim Gyu-jin whom Lee Ungno began studying painting under, and his paintings during his time in Japan. It was confirmed that in order to escape from stereotypical paintings, deep contemplation of nature while painting was his first important principle. This principle, also known as Xieyi (寫意), lasted until the 1950s. In addition, it is highly probable that he understood the dictionary definition of abstract painting, i.e., the meaning of extracting shapes from nature according to the ideas which became important to him after studying in Japan, rather than the theory of abstract painting realized in Western paintings. Lee Ungno himself also stated that the shape of nature was the basis of abstract painting. In other words, abstractive painting and abstract painting are different concepts and based on this, it is necessary to analyze the paintings of Lee Ungno. Finally, I questioned the view that Lee Ungno's abstract paintings of the 1950s were painted as representative of the Xieyi (寫意) mind of literary art painting. Linking traditional literary art painting theory directly to Lee Ungno, who had been active in other worlds in space and time, may minimize Lee Ungno's individuality and make the distinction between traditional paintings and contemporary paintings obscure. Lee Ungno emphasized Xieyi (寫意) in his paintings; however, this might have been an emphasis signifying a great proposition. This is actually because his works produced in the 1950s, such as Self-Portrait (1956), featured painting styles with boldly distorted forms achieved by strong ink brushwork, a style which Lee Ungno defined as 'North Painting.' This is based on the view that it is necessary to distinguish between Xieyi (寫意) and 'the way of Xieyi (寫意) painting' as an important aspect of literary art painting. Therefore, his paintings need a new interpretation in consideration of the viewpoint that he represented abstract paintings according to his own Xieyi (寫意) way, rather than the view that his paintings were representations of Xieyi (寫意), or rather a succession of traditional paintings in the literary artist's style.