• Imaging Science in Dentistry
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• v.38 no.3
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• pp.133-146
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• 2008

Purpose : To observe and evaluate the effects of Simvastatin-induced osteogenesis on the wound healing of defective bone. Materials and Methods : 64 defective bones were created in the parietal bone of 32 New Zealand White rabbits. The defects were grafted with collagen matrix carriers mixed with Simvastatin solution in the experimental group of 16 rabbits and with collagen matrix carriers mixed with water in the controlled group. The rabbits were terminated at an interval of 3, 5, 7, and 9 days, 2, 4, 6, and 8 weeks after the formation of defective bone. The wound healing was evaluated by soft X-ray radiography. The tissues within defective bones were evaluated through the analysis of flow cytometry for the manifestation of Runx2 and Osteocalcin, and observed histopathologically by using H-E stain and Masson's trichrome stain. Results : 1. In the experimental group, flow cytometry revealed more manifestation of Runx2 at 5, 7, and 9 days and Osteocalcin at 2 weeks than in the controlled groups, but there was few difference in comparison with the controlled group. 2. In the experimental group, flow cytometry revealed considerably more cells and erythrocytes at 5, 7, and 9 days in comparison with the controlled group. 3. In the experimental group, soft x-ray radiography revealed the extended formation of trabeculation at 2, 4, 6, and 8 weeks. 4. Histopathological features of the experimental group showed more fibroblasts and newly formed vessels at 5 and 7 days, and the formation of osteoid tissues at 9 days, and the newly formed trabeculations at 4 and 6 weeks. Conclusion : As the induced osteogenesis by Simvastatin, there was few contrast of the manifestation between Runx2 and Osteocalcin based on the differentiation of osteoblasts. But it was considered that the more formation of cells and erythrocytes depending on newly formed vessels in the experimental group obviously had an effect on the bone regeneration.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.4
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• pp.591-598
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• 2021

The digital phase-locked loops(DPLL) is a circuit used for phase synchronization and has been generally used in various fields such as communication and circuit fields. State estimators are used to design digital phase-locked loops, and infinite impulse response state estimators such as the well-known Kalman filter have been used. In general, the performance of the infinite impulse response state estimator-based digital phase-locked loop is excellent, but a sudden performance degradation may occur in unexpected situations such as inaccuracy of initial value, model error, and disturbance. In this paper, we propose a minimum variance finite impulse response filter with optimal horizon for designing a new digital phase-locked loop. A numerical method is introduced to obtain the measured value interval length, which is an important parameter of the proposed finite impulse response filter, and to obtain a gain, the covariance matrix of the error is set as a cost function, and a linear matrix inequality is used to minimize it. In order to verify the superiority and robustness of the proposed digital phase-locked loop, a simulation was performed for comparison and analysis with the existing method in a situation where noise information was inaccurate.

• Korean Journal of Materials Research
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• v.14 no.9
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• pp.676-681
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• 2004

In-situ observation in SBM on the microfracture behavior of coating layer was performed for GA steel sheets that have various Fe contents and thickness of coating layer. In case of cross sectional side of coating layer that was in a tensile stress state during bending, fine perpendicular crack pre-induced during galvannealing grew and propagated rapidly toward the coating surface with the increase of strain. And then it grew and propagated along the ${\Gamma}/Fe$ matrix interface, and combined with the nearest another perpendicular crack. Consequently, flaking occurred. The more Fe content and thickness of coating layer increased, the more average crack interval and flaking resistivity increased. Exfoliation was little observed at coating surface in a tensile stress state.

• Journal of Periodontal and Implant Science
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• v.43 no.6
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• pp.315-322
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• 2013

Purpose: In this study, we investigated the effect of silk scaffolds on one-wall periodontal intrabony defects. We conjugated nano-hydroxyapatite (nHA) onto a silk scaffold and then seeded periodontal ligament cells (PDLCs) or dental pulp cells (DPCs) onto the scaffold. Methods: Five dogs were used in this study. Bilateral 4 mm${\times}$2 mm (depth${\times}$mesiodistal width), one-wall intrabony periodontal defects were surgically created on the distal side of the mandibular second premolar and the mesial side of the mandibular fourth premolar. In each dog, four of the defects were separately and randomly assigned to the following groups: the PDLCcultured scaffold transplantation group (PDLC group), the DPC-cultured scaffold transplantation group (DPC group), the normal saline-soaked scaffold transplantation group, and the control group. The animals were euthanized following an 8-week healing interval for clinical, scanning electron microscopy (SEM), and histologic evaluations. Results: There was no sign of inflammation or other clinical signs of postoperative complications. The examination of cellseeded constructs by SEM provided visual confirmation of the favorable characteristics of nHA-coated silk scaffolds for tissue engineering. The scaffolds exhibited a firm connective porous structure in cross section, and after PDLCs and DPCs were seeded onto the scaffolds and cultured for 3 weeks, the attachment of well-spread cells and the formation of extracellular matrix (ECM) were observed. The histologic analysis revealed that a well-maintained grafted volume was present at all experimental sites for 8 weeks. Small amounts of inflammatory cells were seen within the scaffolds. The PDLC and DPC groups did not have remarkably different histologic appearances. Conclusions: These observations indicate that nHA-coated silk scaffolds can be considered to be potentially useful biomaterials for periodontal regeneration.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5981-5984
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• 2012

Background: Numerous studies have investigated the association of matrix metalloproteinase 1 (MMP1) rs1799750 single nucleotide polymorphism with lung cancer susceptibility, but the findings are inconsistent. Therefore, we performed a meta-analysis to comprehensively evaluate any possible association. Methods: We searched publications from MEDLINE, EMBASE and CNKI databases which assessed links between the MMP1 rs1799750 polymorphism and lung cancer risk. We calculated the pooled odds ratio (OR) and its 95% confidence interval (95%CI) using either fixed-effects or random-effects models. Results: The meta-analysis was based on 9 publications encompassing 4,823 cases and 4,298 controls. The overall results suggested there was a significant association between the MMP1 rs1799750 polymorphism and lung cancer risk (1G vs. 2G: OR = 0.83, 95%CI = 0.73-0.94; 1G1G vs. 2G2G: OR = 0.73, 95%CI = 0.59-0.92; 1G1G vs. 1G2G/2G2G: OR = 0.87, 95%CI = 0.79-0.97; 1G1G/1G2G vs. 2G2G: OR = 0.78, 95%CI = 0.64-0.95). In the subgroup analysis by ethnicity, the association was still obvious in Asians (all P values < 0.05), but there was no association in Caucasians (all P values > 0.05). Conclusions: The MMP1 rs1799750 polymorphism is associated with decreased lung cancer risk, and a race-specific effect may exist in this association.

• Korean Journal of Clinical Pharmacy
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• v.26 no.1
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• pp.70-76
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• 2016

Background: The use of the extracts from evening primrose seeds as a health functional food has been gradually increased. Therefore, the monitoring and screening process has been considerably required for its quality control. Objective: This study aimed to estimate the measurement uncertainty associated with determination of penta-o-galloyl ${\beta}$-D-glucose (PGG) in extracts from evening primrose seeds by high-performance liquid chromatography. Methods: The sources of measurement uncertainty was expressed in accordance with mathematical/statistical theories of GUM & EURACHEM Guide. The expanded uncertainty was calculated by using the relative standard uncertainty between analytical result and sources of uncertainty in measurement (sample weight, final volume, extraction volume, standard solution, matrix and instrument etc). Results: In the results of 95% confidence interval, the uncertainty in measurement was $10,253.34{\pm}1,844.50{\mu}g/kg$ (k = 2.0). Conclusion: In this study, it showed that the value of uncertainty in measurement for determination of PGG in extracts from evening primrose seeds by HPLC has about 18.0% influence on PGG contents of the analytical results. The results would be very useful for the monitoring and screening of evening primrose seeds marketed in Korea for its quality control as dietary supplement.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.86-86
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• 1995

The analysis of membrane receptors for hormones and neurotransmitters has progressed considerably by pharmacological and biochemical means and more recently by the use of specific anti-receptor antibodies. A 14-mer peptide (from Phe102 to Leu115 of ${\beta}$2-adrenergic receptor) was synthesized and this peptide was coupled to carrier protein Keyhole Limpet Hemocyanin(KLH) by glutaraldehyde method. A 0.5mg of KLH-coupled peptide was emulsified with equal volume of complete Freund's adjuvant and injected via popliteal lymph node to each of the three Newzealnd White rabbits. Booster injections were repeated at 4 weeks interval for three times with incomplete Freund's adjuvants. One week after the final injection, serum was prepared from ear artery. Nonspecific immunoglobulins were removed by passing the serum through KLH-Sepharose 6B affinity matrix and further by incubation with bovine lung aceton powder. The titer of the antibody for synthetic peptide which was determined by enzyme linked immunosorbent assay(ELISA) was about l/l,000. The antibody produced in this study revealed 67kDa protein band in the western blot of partially purified guinea pig lung ${\beta}$-adrenergic receptor preparation. The antibody inhibited ${\beta}$-adrenergic antaginist [3H] Dihydroalprenolol binding to soluble ${\beta}$-adrenergic receptor by 25% while control sera did not show any inhibitory effects, The result of this study suggests that the peptide sequence selected in this study may play some important roles in adrenergic receptor-ligand interaction.

• Korean Journal of Occupational Health Nursing
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• v.23 no.2
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• pp.55-66
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• 2014

Purpose: The purpose of this study is to analyze the structural model on the Nursing Task Performance of Hospital Nurses. Methods: Data collection was done by the 200 hospital nurses from May 1st to May 20th, 2013 in Seoul city. The sample variance-covariance matrix was analyzed using AMOS 19.0 and the maximum likelihood minimization function. The goodness of fit was evaluated using the SRMR, RMSEA and its 90% confidence interval, CFI, and TLI. Results: First, hospital nurses' organizational justice and empowerment was not found to have a significant direct effect on nursing task performance. Second, organizational justice and empowerment had a direct effect on job satisfaction and organizational commitment. Third, organizational commitment was found to have a significant direct effect on nursing task performance. Forth, hospital nurses' empowerment was found to have a significant direct effect on nursing task performance. Conclusion: Nurses' nursing task performance was influenced by organizational justice, empowerment, and organizational commitment. In order to increase the degree of nursing task performance in hospital nurse, it is necessary to develop the nursing program and its application considering hospital nurses' organizational justice and empowerment and organizational commitment.

• Korean Journal of Child Studies
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• v.34 no.3
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• pp.93-112
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• 2013

The purpose of this study was to investigate the structural relationships between variables related to the Suicidal Ideation of Adolescences. A total of 923 Middle school students residing in Daegu City completed questionnaires which assessed family adaptability, family cohesion, self-esteem, bullying victimhood, depression and suicidal ideation. The sample variance-covariance matrix was analyzed using AMOS 20.0, and a maximum likelihood minimization function. Goodness of fit was evaluated using the SRMS, RMSEA, and its 90% confidence interval, CFI, and TLI. The results were as follows : First, the variables of family adaptability and family cohesion did not have a statistically significant direct impact on adolescence's suicidal ideation, although they may well have an indirect effect on suicidal ideation through self-esteem, bullying victimhood and depression. Second, Self-esteem and bullying victimhood had significant direct effects on depression and suicidal ideation. Moreover, they also had an indirect effect on suicidal ideation through self-esteem. Third, depression had a substantial direct effect on suicidal ideation. Finally, self-esteem did not indicate a direct effect on bullying victimhood.

• The Korean Journal of Applied Statistics
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• v.28 no.2
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• pp.289-294
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• 2015

Linear mixed models are commonly used in the clinical pharmaceutical studies to analyze repeated measures such as the crossover study data of bioequivalence studies. In these models, random effects describe the correlation between repeated outcomes and variance-covariance matrix explain within-subject variabilities. Bioequivalence analysis verifies whether a 90% confidence interval for geometric mean ratio of Cmax and AUC between reference drug and test drug is included in the bioequivalence margin [0.8, 1.25] performed using linear mixed models with period, sequence and treatment effects as fixed and sequence nested subject effects as random. A Levofloxacin study is referred to for an example of real data analysis.