• Restorative Dentistry and Endodontics
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• v.34 no.2
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• pp.130-136
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• 2009

The aim of this study was to develop a method for measuring the slumping resistance of flowable resin composites and to evaluate the efficacy using rheological methodology. Five commercial flowable composites (Aelitefil flow:AF, Filtek flow:FF, DenFil flow:DF, Tetric flow:TF and Revolution:RV) were used. Same volume of composites in a syringe was extruded on a glass slide using a custom-made loading device. The resin composites were allowed to slump for 10 seconds at $25^{\circ}C$ and light cured. The aspect ratio (height/diameter) of cone or dome shaped specimen was measured for estimating the slumping tendency of composites. The complex viscosity of each composite was measured by a dynamic oscillatory shear test as a function of angular frequency using a rheometer. To compare the slumping tendency of composites, one way-ANOVA and Turkey's post hoc test was performed for the aspect ratio at 95% confidence level. Regression analysis was performed to investigate the relationship between the complex viscosity and the aspect ratio. The results were as follows. 1. Slumping tendency based on the aspect ratio varied among the five materials (AF

• Korean Journal of Heritage: History & Science
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• v.39
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• pp.59-93
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• 2006

Wolseong in Gyeongju is a historic fortress site of Silla constructed under the reign of Pasanisageum that played politically and militarily important roles. The moat surrounding Wolseong had a function of protecting the fortress in wartimes but became a part of gardening in the unified Silla era. Lots of relics have been excavated from Wolseong moat since 1985. Among them a great number and kinds of convex roofing tiles are regarded as invaluable sources to show different aspects of Silla, from its earlier time through to the unified and on. Roofing tiles were widely used for national buildings such as royal palaces, temples and fortresses and even for other popular architecture and have been dug out a lot more than any other relics. Research on them, however, has been done poorly. Vigorous study is in progress with increasing number of roofing tiles coming from many recent excavations, though it has been limited to the studies on general genealogy of patterns and manufacture processes. Thus this essay seeks to find which are dongbeomwas, roofing tiles of a same mold, out of convex tiles with the pattern of a unilobed lotus flower dug out of Wolseong moat. It also attempts to identify dongbeomwas by examining detail characteristics of roofing tiles which have been confusingly termed as yusawa, similar roofing tiles, or donghyeongwa, roofing tiles of the same shape. The significance of identifying dongbeomwas could be emphasized by various facts resulting from researches on dongbeomwas; the ways to identify them correctly, their time sequence and their excavated sites. In conclusion, dongbeomwas were identified out of many kinds of convex tiles. If they were excavated from the same site, they share some common features. The sites where they were dug out also tell what changes were made with passage of time and what relations they had with neighboring Anapji. Since roofing tile molds haven't been found yet, the only way to identify dongbeomwas is to examine details of roofing tiles. Dongbeomwas excavated in Wolseong moat help to discuss the time of each district of it. Meanwhile it should be noted that the term 'dongbeomwa' be used only after exact examining.

• Journal of Technology Innovation
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• v.31 no.3
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• pp.39-73
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• 2023

The field of Management of Technology(MOT) emerged in response to the need for research management within U.S. public research institutions during the 1960s. Since its inception, it has proliferated significantly, being practiced in more than 809 institutions globally and over 19 institutions in Korea, encompassing both research and educational endeavors. Particularly noteworthy is the substantial investment of government resources, primarily channeled through the Ministry of Industry since 2007, which has expeditiously established a comprehensive framework for cultivating graduate-level MOT expertise, marked by both quantitative and qualitative advancements. The educational curriculum in the realm of Korean MOT deviates from foreign counterparts through distinctive pathways, exemplified by its emphasis on industry practice-oriented educational programs, standardization and isomorphism across different schools, as well as its interconnectedness with proximate academic disciplines. This research systematically undertakes an analysis of the curriculum in Korean MOT graduate schools, thereby ascertaining its intrinsic identity and distinct attributes. In this endeavor, a comprehensive examination of eleven principal MOT textbooks(three in Korean and eight in English) is conducted to delineate the primary content of the curriculum across seven thematic domains. Moreover, the study deliberates on its differentiation from neighboring academic disciplines and the definitional attributes of MOT. Subsequently, this analysis also encompasses nine Korean MOT graduate programs, projecting the seven thematic domains onto their respective curricula. The findings illuminate that within the context of Korean graduate programs, a substantial proportion of the curriculum, amounting to 62.5%, is dedicated to facets encompassing the operational aspects of technology management within corporate contexts, technology management specific to varying industries and technologies, and collaborative endeavors between academia and industry in the form of projects and seminars. Evidently, the Korean approach to technology management education is notably geared towards the cultivation of adept practitioners capable of executing technology management functions at a mid-tier managerial level, aligned with the exigencies of regional industries. Grounded in the analysis of technology management curricula, this study extrapolates implications for the future trajectory of MOT education in Korea, encompassing a consideration of the stages of industrial development. It underscores the necessity to augment the educational curricula pertaining conceptual foundation of technology and innovation, strategic perspectives of technology and innovation, and the socio-economic context of technology management.

• Journal of Genetic Medicine
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• v.4 no.2
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• pp.160-166
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• 2007

Purpose : The ${\beta}$-adrenoceptors are pharmacologically classified into ${\beta}_1$-, ${\beta}_2$- and ${\beta}_3$-adrenoceptor. The gene of each subtype has polymorphisms related to their function (${\beta}_1$-adrenoceptor: Ser49Gly, ${\beta}_2$-adrenoceptor: Gln27Glu, ${\beta}_3$-adrenoceptor: Trp64Arg). The objectives of this study were to analyse the allelic and genotypic distribution of the representative polymorphism of ${\beta}$-adrenoceptors in preeclampsia and to investigate whether combined genotype of ${\beta}$-adrenoceptors may be associated with preeclampsia. Methods : Blood samples were collected from a Korean population (159 preeclamptic pregnancies and 168 normotensive pregnancies). The ${\beta}_1$-, ${\beta}_2$- and ${\beta}_3$-adrenoceptor genotypes was determined using polymerase chain reaction-restriction fragment length polymorphism. Results : There were no differences in allelic and genotypic distribution of ${\beta}_1$- and ${\beta}_2$-adrenoceptor polymorphisms between the two groups. However, the Arg allele of ${\beta}_3$-adrenoceptor polymorphism were more frequent in preecalmpsia than in controls (P<0.05, OR=1.57, 95% CI=1.01-2.46). Moreover, prevalence of genotype carrying heterozygote of ${\beta}_3$-adrenoceptor polymorphism was increased in preeclampsia compared with controls (P<0.05, OR 1.76, 95% CI 1.06-2.92). When combination of the three polymorphisms were evaluated, pregnancies with the particular combined genotype that is consisted of heterozygote of ${\beta}_1$-, ${\beta}_3$-adrenoceptor and wild homozygote of ${\beta}_2$-adrenoceptor (Ser/Gly, Gln/Gln, Trp/Arg), showed a significant increase in the risk of preeclampsia (P<0.05, OR=3.01, 95% CI 1.12-8.08). Conclusion : A particular combined genotype (Ser/Gly, Gln/Gln, Trp/Arg) of - adrenoceptors was associated with the risk of preeclampsia.

• Journal of Life Science
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• v.27 no.3
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• pp.295-300
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• 2017

This study examined the association between genotypes of the isocitrate dehydrogenase 3, beta subunit (IDH3B) gene and economic traits in an $F_2$ population of Duroc and Jeju (South Korea) native black pigs (JBPs). The genotypes was determined the presence/absence of a 304-bp insertion/deletion fragment in the promoter region of the IDH3B gene for JBP, Duroc, and their $F_1$ and $F_2$ progeny. Three genotypes (AA, AB and BB) were found in the $F_1$ and $F_2$ populations, but there was no AA genotype found in JBP and no BB in Duroc. Association analysis results showed the significant differences with carcass weights (CW), backfat thicknesses (BFT) and eye muscle area (EMA) (p<0.05), but not with growth traits including body weights and average daily gains at different stages, reproductive traits including teat numbers, and crude fat contents (CFAT) measured in longissimus dorsi (p>0.05). The $F_2$ pigs possessing the IDH3B BB homozygote had heavier CW ($72.92{\pm}11.133kg$), thicker BFT ($25.75{\pm}6.06mm$), and larger EMA ($23.82{\pm}4.825cm^2$) than those from the other genotypes (p<0.05). These results were estimated that there are biological roles related with IDH3B genotypes resulting development of EMA, BFT, and CW but not with intramuscular fat deposition during late period of pig production. Our findings suggest that the 304-bp insertion allele of porcine IDH3B may be a genetic marker for marker assistant selection for improving meat productivity of the Jeju Black pig and Duroc-related molecular breeding systems.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.1
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• pp.24-33
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• 2016

Mucopolysaccharidosis type VI (MPS VI) is a rare disease caused by the mutation of ARSB with prevalence range from 1/5,000 in northeast Brazil to 1/2,057,529 births in Czech Republic. In Asia, there is only one published figure in Taiwan of about 1/833,000 births. The exact prevalence in the Korean population is unknown, but we estimated the incidence of MPS VI is about 0.03/100,000 live births. Enzyme replacement therapy (ERT) with recombinant human Arylsulfatase B (rhASB) is a modality for the treatment of MPS VI that reduces the excretion of urine glycosaminoglycan (GAG) and improves joint motion, pulmonary function, and endurance. We presented the clinical features, molecular analysis and outcome of ERT in three Korean MPS VI patients. All patients had the typical characteristic clinical features of MPS IV. Short stature, dysostosis multiplex, corneal opacity and valvular heart disease were found at first presentation, while restrictive lung disease and carpal tunnel syndrome developed later in all patients. Molecular analysis demonstrated novel missense and nonsense mutation in the patients, including p.Ile 67Ser, p.Gly328Arg, $p.Arg191^*$, p.Asp352Asn, and p.Gly17Asp. After ERT, urine GAG was decreased in all patients. Skeletal involvement, corneal opacity, heart valve abnormalities and pulmonary function were not improved with ERT, but it had a better outcome on regarding joint motion and endurance. One patient underwent allogeneic bone marrow transplantation (BMT) prior to ERT, but their clinical response was not improved much after BMT. This study demonstrates clinical phenotypes and molecular analysis of the severe form of MPS VI in Korean patients.

• Journal of Life Science
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• v.34 no.7
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• pp.465-475
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• 2024

Lactiplantibacillus plantarum K9 is a probiotic strain that can be utilized from various bioactive substances isolated from Protaetia brevitarsis seulensis larvae. In this study, a genetic analysis of L. plantarum K9 revealed the existence of a bacterial chromosome and three plasmids. The glycolysis pathway and pentose phosphate pathway were examined for their normal functioning via an analysis of the core metabolic pathways of L. plantarum K9. Since the key enzymes, fluctose-1,6-bisphospatase (EC: 3.1.3.11) and 6-phosphogluconate dehydratase (EC: 4.2.1.12)/2-keto-deoxy-6-phosphogluconate (KDPG) aldolase (EC: 4.2.1.55), of gluconeogenesis and the ED pathway were not identified from the L. plantarum K9 genome, we suggest that gluconeogenesis and the ED pathway are not performed in L. plantarum K9. Additionally, while some enzymes, related to fumarate and malate biosyntheses, involved in the TCA cycle were identified from L. plantarum K9, the enzymes associated with the remaining TCA cycle were absent, indicating that the TCA cycle cannot proceed. Meanwhile, based on our findings, we propose that the oxidative electron transport system performs class IIB-type (bd-type) electron transfer. In summary, we assert that L. plantarum K9 performs homolactic fermentation, executes gluconeogenesis and the pentose phosphate pathway, and carries out energy metabolism through the class IIB-type oxidative electron transport system. Therefore, we suggest that L. plantarum K9 has relatively high lactic acid production, and that it has excellent antibacterial activity, as a result, compared to other lactic acid bacterial strains. Moreover, we speculate that L. plantarum K9 has an oxidative electron transport capability, indicating that it is highly resistant to oxygen and suggesting that it has fine cultivation characteristics, which collectively make it highly suitable for use as a probiotic.

• Korean Journal of Agricultural Science
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• v.7 no.1
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• pp.12-26
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• 1980

A new, improved maize varieties are greatly needed to meet the national demand for the maize, and a new germplasm should be investigated to supply necessary breeding materials for the required maize breeding. The Korean local maize lines, which has never been wholly studied for the purpose of breeding should be enough to supply such breeding materials at least in Korea. The objectives of this study were to maintain useful Korean local lines, to investigate good plant characters and to analyze the Korean local maize lines in the respect of genetic make-up. A total of 820 lines and 200 lines were used for the present study. Lines to maintain were planted at experimental farm of the Crop Experiment Station, Office of Rural Development, Suwon and the lines to study genetic make-up were planted in Dae-jon. The summarized results are as follows : 1. A total of 1200 lines from 820 collections were sibbed for future use. 2. Two hundred collection were sibbed, selfed and testcrossed for genetic study in 1980. 3. Ten lines were surely confirmed as resistant lines to virus disease epidemic in most introduced maize varieties. 4. A dozen Lines were having three to four ears per plant. 5. Five lines were showing three to four tillers per plant. 6. One of the most significant and important finding through the study was to obtain the lines with three to four tillers bearing all together eight to nine ears. The lines of multi-ears and multi-tillers must have great breeding potential for the future use. 7. A great variation was observed in the tasselling days, 100 kernel weight and protein content. 8. From the genetic study of local maize lines for plant height and 100 kernel weight, the following findings were obtained. a. On the average six percent of inbreeding depression expressed in percent decrease over sibbed counterpart were found for the plant height. b. Fourty percent of heterosis expressed in percent increase over sibbed counterpart were observed in the plant height. c. The homogeneity or degree of homozygosity calculated from heterosis minus inbreeding depression was on the average 34 percent for plant height. d. The average inbreeding depression expressed in percent decrease over sibbed counterpart was 15 percent for 100 kernel weight. e. The average heterosis expressed in percent increase over sibbed counterpart was 43 percent for 100 kernel weight. f. The degree of homozygosity calculated from the heterosis minus inbreeding depression was 28 percent for 100 kernel weight.

• Journal of Life Science
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• v.26 no.4
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• pp.414-418
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• 2016

This study tested the association between genetic polymorphisms of the isocitrate dehydrogenase 3, beta subunit (IDH3B) gene and economic traits in an F₂ crossbred population of Landrace × Jeju (South Korea) Black pigs. A 304-bp insertion/deletion mutation in promoter region was screened for determining genotypes of the IDH3B gene in a total of 1,105 F₂ pigs. Three genotypes (AA, AB, and BB) were identified in the founder, F₁, and F₂ populations. Association analysis showed significant differences in carcass weights (CW), backfat thicknesses in three positions of the body (4^th-5^th ribs, BF5; 11^th-12^th ribs, BF12; 13^th rib-1^st lumbar, BFL), and carcass lengths (CL) (p<0.05), but not in meat color (MC), eye muscle area (EMA), or marbling scores (MARB) (p>0.05). The F₂ IDH3B BB homozygotes showed heavier CW (80.790±0.725 kg) and shorter CL (101.875±0.336 cm) than the other genotypes (p<0.05). In addition, the BF levels between the 4^th - 5^th and 11^th - 12^th vertebrae were thicker in the carcasses of pigs with the IDH3B BB genotype than with the other genotypes (p<0.05). These results suggested that genetic variations in the IDH3B gene may serve as molecular genetic markers for improving the Landrace × Jeju Black pig crossbreeding systems.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.151-159
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• 2002

Genetic map and molecular marker have a great importance in improving and facilitating crop breeding program as well as in genome analysis and map-based cloning of genes representing desirable characters. This study aimed at developing RAPD markers and constructing a genetic linkage map using 82 BC$_1$F$_1$individuals originated from the cross between '835' and B$_2$in radish (Raphanus sativus L.). One of the parents for genetic linkage map construction, '835'(P$_1$) of egg type is susceptible to Fusarium wilt and have medium resistance to virus infection and the other parent, B$_2$(P$_2$) of round type, is susceptible to Fusarium wilt and virus, Screening of 394 RAPD primers in BC$_1$F$_1$) population resulted in selecting 128 polymorphic markers which displayed 1:1 segregation pattern. Two markers failed to display 1:1 segregation and showed the segregation ratio skewed to maternal genotype. Selected markers were categorized into 14 linkage group based on LOD score represented by MAPMAKER/EXP program. Five groups composed of single marker among them were excluded from the linkage map, and consequently, the remaining groups are well matched with the number of radish chromosome (n＝9). The linkage map constructed with 128 markers covers 1,688.3 cM and the average distance between markers was 13.8 cM. For developing STS marker, we determined the partial nucleotide sequence of OPE10 marker at both ends and designed a oligonucleotide primer pair based on this sequence. STS PCR using the primer pair displayed a single, clear band of which segregation is perfectly matched with that of OPE10 marker. This implies that RAPD markers could readily convert into clear and reliable STS markers.