• Restorative Dentistry and Endodontics
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• v.28 no.1
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• pp.72-79
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• 2003

The objective of this in vitro study was to evaluate the efficacy of a Ca(OH)$_2$removal before and after early coronal flaring using different types of instruments. 100 plastic blocks with 30$^{\circ}$artificial curved canals were used in this study and randomly divided into a control group and 4 experimental groups(GG, OS, GT, PT Group) 20 teeth each. The canals were instrumented, and Ca(OH)$_2$was temporary filled into the each canal. Irrigation was peformed with Max-i-Probe 25- 30-gauge probes before and after recapitulation. The results of this study were as follows 1. There were no significant difference among the groups in size of irrigating needle(p<0.05). 2. There was a significant difference between before and after recapitulation regardless size of irrigating needle(p<0.05). 3. Before recapitulation, there was a significant difference between 25- and 30-gauge needle in all groups(P<0.05). 4. After recapitulation, there was a significant difference between 25- and 30-gauge needle in the control group(p<0.05). But there were no significant difference among the experimental groups. It is concluded that the effectiveness of canal irrigation was decided to the depth of irrigating needle into the canal. The effect of canal irrigation tend to facilitate by the early coronal flaring. The recapitulation was the most effective during canal irrigation regardless the size of irrigating needle. Therefore, the recapitulation is a mandatory way to facilitate the effectiveness of canal irrigation during canal enlargement.

• Journal of The Korean Association For Science Education
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• v.23 no.4
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• pp.386-400
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• 2003

This paper presents an analysis of the Developmental Approaches in Science, Health and Technology (DASH) program, a K-6 curriculum developed by the Curriculum Research & Development Group (CRDG) at the University of Hawaii employing the curriculum analysis framework created by Posner. Using this framework the analyst found that the DASH design is based on the research on learning, teaching, and assessment now driving efforts to reform science education at the elementary level. DASH embraces the constructivist idea that learning is a personal and social process and the recapitulation model that new concepts are built out of theories previously learned. DASH provides an understandable, exciting, and memorable experience in the operations of science, health, and technology, and develops their capacity to use the skills and knowledge of science, health, and technology both in and outside school. A number of studies of DASH have examined its functionality, effectiveness of pedagogy and what students learn. The innovative nature of DASH necessitated a multidimensional assessment that included both quantitative and qualitative research techniques. Ongoing development of the DASH program in the research setting of a university laboratory school permits ever deeper connections with emerging curriculum theory and curriculum practice, and allows new linkages as ideas are tested in research classrooms.

• The Journal of Economics, Marketing and Management
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• v.2 no.4
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• pp.1-19
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• 2014

The rule of Islam is simple: if you advance a loan, you are entitled to receive your capital only and nothing more. If you wish to secure profit you should enter into a partnership and become a shareholder. Prohibitions against interest are not peculiar to Islam. If we were to trace back through history, a number of examples of such prohibitions can be found in the early Greek, Roman and Rabinnical thought. With the decline of the influence of the Catholic Church interest transactions become legal and stimulated giant Western corporations which forged capitalist imperialism. The practice of charging interest (usury) now dominated Western law and ethics for over a millennium. But, the Western or capitalist economic system has proven a failure in its quest for economic justice, which serves to benefit all in society, both the rich and the poor. In particular, capitalism is currently causing a terrifying scenario of making the rich richer and the poor poorer due to interest charges. An alternative banking model, called Islamic finance and banking, is evoked in this study in order to depress financial exploitation by banking institutions.

• Journal for History of Mathematics
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• v.26 no.5_6
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• pp.389-400
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• 2013

The article makes a discussion to conceptualize a histo-genetic principle in the real historical view point. The classical histo-genetic principle appeared in 19th century was founded by the recapitulation law suggested by biologist Haeckel, but recently it was shown that the theory on it is no longer true. To establish the alternative rationale, several metaphoric characterizations from the history of mathematics are suggested: among them, problem solving, transition of conceptual knowledge to procedural knowledge, generalization, abstraction, circulation from phenomenon to substance, encapsulation to algebraic representation, change of epistemological view, formation of algorithm, conjecture-proof-refutation, swing between theory and application, and so on.

• Journal of the Daesoon Academy of Sciences
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• v.34
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• pp.263-292
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• 2020

Among the various influences from other ancient cultures observable in Daesoon Jinrihoe, the reference to and the transformation of Feng-Shui is especially prominent. In The Canonical Scripture, Feng-Shui culture is mentioned frequently. Feng-Shui culture in The Canonical Scripture not only draws upon a great deal of traditional Feng-Shui Theory but also inserts many innovations. It is worth noting that the understanding of Feng-Shui culture through Daesoon Jinrihoe's doctrine makes The Canonical Scripture unique. Based upon the conscientious recapitulation of the relevant contents in The Canonical Scripture, this essay aims at dealing with the Feng-Shui Culture of Daesoon Jinrihoe in regards to three aspects: Terrestrial Energy, Mountain Shape and Luminous Courts (Mingtang). A better understanding of the profound contents and sacred significance of The Canonical Scripture can naturally be attained from applying a Feng-Shui culture perspective.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.2
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• pp.75-81
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• 2018

Objective: Recapitulation of the spermatogenesis process in vitro is a tool for studying the biology of germ cells, and may lead to promising therapeutic strategies in the future. In this study, we attempted to transdifferentiate Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) into male germ cells using all-trans retinoic acid and Sertoli cell-conditioned medium. Methods: Human WJ-MSCs were propagated by the explant culture method, and cells at the second passage were induced with differentiation medium containing all-trans retinoic acid for 2 weeks. Putative germ cells were cultured with Sertoli cell-conditioned medium at $36^{\circ}C$ for 3 more weeks. Results: The gene expression profile was consistent with the stage-specific development of germ cells. The expression of Oct4 and Plzf (early germ cell markers) was diminished, while Stra8 (a premeiotic marker), Scp3 (a meiotic marker), and Acr and Prm1 (postmeiotic markers) were upregulated during the induction period. In morphological studies, approximately 5% of the cells were secondary spermatocytes that had completed two stages of acrosome formation (the Golgi phase and the cap phase). A few spermatid-like cells that had undergone the initial stage of tail formation were also noted. Conclusion: Human WJ-MSCs can be transdifferentiated into more advanced stages of germ cells by a simple two-step induction protocol using retinoic acid and Sertoli cell-conditioned medium.

• BMB Reports
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• v.51 no.10
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• pp.526-531
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• 2018

Protein-Protein Interactions (PPIs) play essential roles in diverse biological processes and their misregulations are associated with a wide range of diseases. Especially, the growing attention to PPIs as a new class of therapeutic target is increasing the need for an efficient method of cell-based PPI analysis. Thus, we newly developed a robust PPI assay (SeePPI) based on the co-translocation of interacting proteins to the discrete subcellular compartment 'processing body' (p-body) inside living cells, enabling a facile analysis of PPI by the enriched fluorescent signal. The feasibility and strength of SeePPI (${\underline{S}}ignal$ ${\underline{e}}nhancement$ ${\underline{e}}xclusively$ on ${\underline{P}}-body$ for ${\underline{P}}rotein-protein$ ${\underline{I}}nteraction$) assay was firmly demonstrated with FKBP12/FRB interaction induced by rapamycin within seconds in real-time analysis of living cells, indicating its recapitulation of physiological PPI dynamics. In addition, we applied p53/MDM2 interaction and its dissociation by Nutlin-3 to SeePPI assay and further confirmed that SeePPI was quantitative and well reflected the endogenous PPI. Our SeePPI assay will provide another useful tool to achieve an efficient analysis of PPIs and their modulators in cells.

• Genomics & Informatics
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• v.14 no.3
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• pp.85-89
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• 2016

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that affects multiple organ systems. Although the etiology of SLE remains unclear, it is widely accepted that genetic factors could be involved in its pathogenesis. A number of genome-wide association studies (GWASs) have identified novel single-nucleotide polymorphisms (SNPs) associated with the risk of SLE in diverse populations. However, not all the SNP candidates identified from non-Asian populations have been validated in Koreans. In this study, we aimed to replicate the SNPs that were recently discovered in the GWAS; these SNPs have not been validated in Koreans or have only been replicated in Koreans with an insufficient sample size to conclude any association. For this, we selected five SNPs (rs1801274 in FCGR2A and rs2286672 in PLD2, rs887369 in CXorf21, rs9782955 in LYST, and rs3794060 in NADSYN1). Through the replication study with 656 cases and 622 controls, rs1801274 in FCGR2A was found to be significantly associated with SLE in Koreans (odds ratio, 1.26, 95% confidence interval, 1.06 to 1.50; p = 0.01 in allelic model). This association was also significant in two other models (dominant and recessive). The other four SNPs did not show a significant association. Our data support that FCGR polymorphisms play important roles in the susceptibility to SLE in diverse populations, including Koreans.

• Biomedical Science Letters
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• v.23 no.2
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• pp.133-137
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• 2017

Periodontitis is the major causation of tooth loss in the elderly population. Multiple risk factors include oral microorganisms, smoking, metabolic syndrome, and genetic factors influence periodontitis development. In this study, we conducted a replication study of using previous Korean GWAS results by examining an independent population. The study population was recruited from Mir Dental Clinic, Daegu, Korea. In total, 93 samples were evaluated from July 2016 to January 2017. The sample groups include relatively older patients (>60 years) with no periodontitis (n = 31) and relatively younger patients (range 40~60 years) with severe periodontitis (n = 62). A total of seven markers which were previously reported to be associated with periodontitis were genotyped. Among the seven SNPs, rs16846206 and rs2392510 showed a significant association by logistic regression analysis and Chi square test, respectively. The former SNP showed significant association with severe periodontitis, whereas this study also showed same tendency in which individuals with the minor allele are significantly more frequent in cases than those in controls. The SNP is located on a coding gene (SLC9C2), where the alanine residue 505 is replaced by glycine (Ala505Gly). The later SNP was significant when differed between case and control groups, but there was no significance by logistic regression analysis when controlled for age and sex as covariant. Although the study population size examined in the current study was relatively smaller compared to previous studies, our results implicated that at least the two SNPs (rs16846206 and rs2392510) might be important candidates for the further genetic study.

• Genomics & Informatics
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• v.17 no.4
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• pp.48.1-48.6
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• 2019

Over the last decade, genome-wide association studies (GWASs) have provided an unprecedented amount of genetic variations that are associated with various phenotypes. However, previous GWAS were mostly conducted in European populations, and these biased results for non-Europeans may result in a significant reduction in risk prediction for non-Europeans. An issue with the early GWAS was the winner's curse problem, which led to misleading results when constructing the polygenic risk scores (PRS). Therefore, more non-European population-based studies are needed to validate reported variants and improve genetic risk assessment across diverse populations. In this study, we validated 422 variants independently associated with glycemic indexes, liver enzymes, and type 2 diabetes in 125,872 samples from a Korean population, and further validated the results by assessing publicly available summary statistics from European GWAS (n = 898,130). Among the 422 independently associated variants, 284, 320, and 361 variants were replicated in Koreans, Europeans, and either one of the two populations. In addition, the effect sizes for Koreans and Europeans were moderately correlated (r = 0.33-0.68). However, 61 variants were not replicated in both Koreans and Europeans. Our findings provide valuable information on effect sizes and statistical significance, which is essential to improve the assessment of disease risk using PRS analysis.