• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.299-306
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• 2018

The aim of this study was to evaluate the effect of etching time and bonding agents on bond strength of sealant applied to the occlusal surface of primary molars. Forty non-carious exfoliated human primary molars were included in the study. The teeth were randomly divided into 4 groups for measurement. For group I, no acid etching treatment was used. For group II, III, and IV, acid etching gels were applied on the occlusal surface for 15, 30, and 60 seconds, respectively. Each group was divided into 2 subgroups; one group was treated with bonding agents on the enamel while the other was not. Microtensile bond strength was evaluated using a universal testing machine. There were no statistically significant differences in bond strength with varying duration of etching among groups. The results revealed that the use of bonding agents prior to application of fissure sealant increased the bond strength(p < 0.05). It could be concluded that etching time greater than 15 seconds does not significantly enhance the bond strength, but the use of bonding agents as an intermediate layer between the primary molar and fissure sealant would be beneficial in increasing the bond strength.

• Journal of Life Science
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• v.27 no.1
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• pp.72-77
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• 2017

Inorganic iron is essential for various metabolic processes, including RNA synthesis, electron transport, and oxygen detoxification in microorganisms. Many bacterial pathogens compete for iron acquisition in diverse environmental condition such as host. Salmonella Typhimurium SL1344 also requires inorganic iron as a cofactor for growth. When a M9 minimal liquid medium was supplemented with ethylenediamine di-o-hydroxyphenylactic acid (EDDA) which acts as an iron-chelating agent, growth of Salmonella Typhimurium SL1344 in the supplemented medium was completely arrested by deficient of useful iron under iron-depleted condition. However, a number of siderophores, which are small, high-affinity iron chelating compounds secreted by microorganisms such as bacteria and fungi, were produced for utilization of restricted iron under iron-depleted condition. A M9 minimal liquid medium complemented with human transferrin (hTf)-iron complex turned completely off production of siderophores, but growth of Salmonella Typhimurium SL1344 maintained level similar to compare one complemented with iron (III) chloride (FeCl3). This means that human transferrin (hTf)-bound iron can utilize via directly interaction with Salmonella Typhimurium SL1344 without productions of siderophores. Through construction and analysis of negative mutant for utilization of human transferrin (hTf)-bound iron, we confirm that the bacterium can directly use human transferrin (hTf)-bound iron without extracellularly intermediated carriers such as siderophores.

• The Korean Journal of Applied Statistics
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• v.21 no.1
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• pp.35-51
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• 2008

Comparative studies in Phase III clinical trials quite often involve two or more equally important endpoints, and one cannot select primary endpoint from them. O'Brien(1984) proposed for continuous endpoints the OLS and GLS statistics as milti-variate test statistics. Pocock et al. (1987) mentioned the possibility of analyzing a mixture of data types, such as quantitative, binary and survival data types, with the OLS and GLS statistics, but the authors did not explore problems in combining several endpoints of different types. Furthermore, they did not perform a simulation study to assess the efficiencies of the OLS and GLS statistics for endpoints of a mixture of data types. In this paper, we propose the combining methods of correlated P-values for the analysis of multiple endpoints, and compare the efficiencies of this method with those of OLS and GLS statistics for a mixture of data types with a simulation study. Among the several methods of combining P-values that are more advantageous than combining of OLS and GLS statistics, method B maintains nominal significance levels and is more efficient, while method F and G have type I error rates that are larger than the specified significance levels, which might occasionally lead to a wrong conclusion.

• Journal of Trauma and Injury
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• v.33 no.1
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• pp.13-17
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• 2020

Purpose: Accurate and appropriate prehospital field triage is essential for a trauma system. The Korean trauma system (established in 2014) uses the trauma field triage algorithm of the United States Centers for Disease Control and Prevention (CDC). This study evaluated the suitability of the CDC field triage criteria for major trauma cases (injury severity score >15) in Korea. Methods: This retrospective cohort study evaluated trauma patients who presented at the authors' regional trauma center from January 1 to May 7, 2017. The undertriage and overtriage rates of each CDC field triage step were calculated. Receiver operating characteristic curves were constructed, and the area under the curve (AUC) was evaluated for each step. Results: Among the 1,009 enrolled patients, 168 (16.7%) had major trauma. The undertriage/overtriage rates of each step (steps I, II, III, and IV) of CDC field triage were 9.2%/47.4%, 6.3%/50.8%, 4.5%/59.4%, and 5.3%/78.9%, respectively. The AUC values of each CDC triage step were 0.722, 0.783, 0.791, and 0.615, respectively. The AUC values of the separate components of each step (physiologic criteria, anatomic criteria, mechanism-of-injury criteria, and special considerations) were 0.722, 0.648, 0.647, and 0.456, respectively. Conclusions: The CDC field triage system is acceptable, but not ideal, for Korean trauma care. If we follow the protocol, it would be preferable to omit step IV. The Korean Triage and Acuity Scale may be a good indicator for in-hospital triage. However, a new triage protocol that is simple to estimate on-scene while having good performance should be developed.

• Journal of Technology Innovation
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• v.19 no.1
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• pp.1-27
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• 2011

This paper aims to measure and analyze R&D productivities and efficiencies of 17 major OECD countries including Korea over the 1984-2008 period by using the Malmquist Productivity Index and Data Envelopment Analysis, classifying R&D performance into an output and outcome aspects. It also searches the Korea's current status and characteristics in each R&D stage to enhance Total Factor Productivity (TFP) compared with other developed countries. Our major findings are the followings: (i) Korea's productivity index of R&D input vis-a-vis R&D output is very high (13.39% annual growth rate) compared with those of major advanced countries, whereas the annual average of efficiency index is very low (0.33), i.e. Korea's technical efficiency index has risen to 0.83 at the last time series started at 0.10 point and come up to the level of major advanced countries. (ii) the Korea's productivity index of R&D output vis-a-vis R&D outcome is very low (14.02% annual reduction rate) compared with those of major advanced countries, whereas the annual average of efficiency index is very high (0.22), i.e. Korea's integrated frontier technical efficiency index has dropped to 0.057 at the last time series started at 1.00 point and coming up to the level of major advanced countries. (iii) The productivity of R&D input vis-a-vis R&D outcome is positively correlated with that of R&D output vis-a-vis R&D outcome and the growth of R&D input factors. In a nutshell, it implicates that the effort to take advantage of R&D outputs, namely establishing the diffusion and commercialization system of technical knowledge to the level of developed countries, should be strengthened over that on the growth of R&D investment and output for enhancing R&D productivity and efficiency in Korea.

• Radiation Oncology Journal
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• v.35 no.3
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• pp.233-240
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• 2017

Purpose: To validate the 8th edition of the American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) TNM staging system for human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) and investigate whether a modified classification better reflects the prognosis. Materials and Methods: Medical records of patients diagnosed with non-metastatic HPV-related OPSCC between 2010 and 2016 at a single institution were retrospectively reviewed. HPV status was determined by immunohistochemical analysis of p16 and/or HPV DNA polymerase chain reaction (PCR). We reclassified TNM stage T0-1 and N0-1 as group A, T2-3 or N2 as B, and T4 or N3 as C. Survival analysis according to 8th AJCC/UICC TNM staging and the modified classification was performed. Results: Of 383 OPSCC patients, 211 were positive for HPV DNA PCR or p16. After exclusion, 184 patients were included in this analysis. Median age was 56 years (range, 31 to 81 years). Most primary tumors were in the palatine tonsil (148 tumors, 80%). The eighth AJCC/UICC TNM classification could not differentiate between stage I and II (p = 0.470) or II and III (p = 0.209). Applying modified grouping, the 3-year overall survival rate of group A was significantly higher than that of group B and C (98% vs. 91%, p = 0.039 and 98% vs. 78%, p < 0.001, respectively). Differentiation between group B and C was marginally significant (p = 0.053). Conclusion: The 8th AJCC/UICC TNM staging system did not clearly distinguish the prognosis of stage II from that of other stages. Including the T2N0-1 group in stage II may improve prognostic stratification.

• Korean Journal of Veterinary Research
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• v.48 no.4
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• pp.441-449
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• 2008

The genus Lactobacillus is the largest of the genera included in lactic acid bacteria and is associated with mucosal membranes of human and animal. Only a few Lactobacillus plasmid-encoded functions have been discovered and used. In this study, a novel plasmid (pILR091) was isolated from a wild L. reuteri isolated from pig and described the characteristics of its replicons, genetic organization, and relationship with other plasmids. After digestion of the plasmid, pILR091, with SalI, plasmid DNA was cloned into the pQE-30Xa vector and sequenced. The complete sequence was confirmed by the sequencing of PCR products and analyzed with the Genbank database. The isolate copy number and stability were determined by quantitative-PCR. The complete sequence of L. reuteri contained 7,185 nucleotides with 39% G-C content and one cut site by two enzymes, SalI and HindIII. The similar ori sequence of the pC194- rolling circle replication family (TTTATATTGAT) was located 63 bp upstream of the protein replication sequence, ORF 1. Total of five ORFs was identified and the coding sequence represented 4,966 nucleotides (70.4%). ORF1 of pILR091 had a low similarity with the sequence of pTE44. Other ORFs also showed low homology and E-values. The average G-C content of pILR091 was 39%, similar with that of genomic DNA. The copy number of pILR091 was determined at approximately 24 to 25 molecules per genomic DNA. These results suggested that pILR091 might be a good candidate to construct a new vector, which could be used for cloning and expression of foreign genes in lactobacilli.

• Water for future
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• v.15 no.3
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• pp.49-55
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• 1982

The purpose of this study is to examine the methods of estimation, comparing U.S. SCS method and $\Phi$-index with effective rainfall. And also comparision was made among SCS method, Chow method and Mockus method as to the peak discharge of design storm hydrograph by small river basin. Hydrological data of the Shin river basin which was used in this study and the results of study are as follow; 1) As a result of applying the SCS method to determine the effective rainfall out of total rainfall, it turned out that the everage CN of the basin as obtained by the analysis of hydrologic soil-cover complex was varied as follows; AMC-I was 27.9%, AMC-II 16.4%, AMC-III 8.1% less than the value given by SC method using discharge measurement. 2) The comparision of effective rainfall by the ungaged SCS method with that of gauged $\Phi$-index method showed that the $\Phi$-index method showed that the $\Phi$-index method gives large value by 4.7% to those given by hydrograph. The result of analysis by the SCS method resulted in great difference from discharge measurement. 3) The comparision of SCS method, Chow method, and Mockus method showed that dimensionless hydrograph of SCS method and Chow method were close to the peak discharge of the gauged unit hydrograph, while the other methods gave far different results. 4) Attempts were made, for a better adaptation to the Shin river basin, to introduce lag time formula constant of dimensionless hydrograph of the SCS method by using the peak discharge of the gauged flow hydrograph.

• Journal of Chest Surgery
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• v.35 no.4
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• pp.303-306
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• 2002

Patients with severe Ebstein's anomaly showing in the neonatal period, represent progressive cardiac enlargement with pulmonary hypoplasia and functional pulmonary atresia with patent ductus alteriosus-dependent pulmonary circulation. Biventricular repair in these patients had been mostly unsuccessful except for Starnes' procedure that converts the anatomy to single ventricle physiology for Fontan procedure. A 4-days old male was admitted with the diagnosis of severe Ebstein's anomaly with anatomic pulmonary atresia and severe cardiac enlargement. He successfully underwent biventricular repair with vertical plication method of atrialized right ventricle, tricupid annuloplasty, transannular right ventricular outflow tract reconstrulltion, atrial septal defect patch closure with fenestration, and right atrial reduction angioplasty Postoperatively, cardiothoracic ratio was significantly reduced and mild tricuspid regurgitation was remnant in echocardiography. The patient is currently 10 months old and is fully active without restrictions.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.262-271
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• 2014

The purpose of this study was to find the effect of Day Hospital Rehabilitation programs on gross motor function in children with cerebral palsy. The subjects were 57 children with spastic cerebral palsy with no previous botulinum toxin injection or operation history within 6 months. The Gross Motor Function Measure(GMFM) score and Gross Motor Function Classification System(GMFCS) were used to evaluate as functional change and functional level. The Programs for Day Hospital Rehabilitation period for cerebral palsy children was 8 weeks. The results of the study are as follows: 1, GMFM Score of pre- and post-programs for Day Hospital Rehabilitation showed the statistically significant difference(p <.001). 2, The age group in 1-2 was higher than age 5-6 group, 3-4 was higher than age 5-6 group by Post-hoc analysis. Lastly, there was significantly different of GMFM in GMFCS level(p<.05), especially mild(GMFCS level I) and moderate(GMFCS level II, III) of CP showed that gross motor function was significantly different than severe(GMFCS level IV, V). The programs for Day Hospital Rehabilitation was effective on gross motor function for children with cerebral palsy, and for early intervention needs to mild, moderate CP, and below age 4 group.