• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.258-270
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• 2012

Purpose: Use of inappropriate statistical methods may lead to incorrect conclusions and a waste of valuable resources. The goal of this study was to assess the frequency and the types of several common statistical errors in the published articles of the Journal of the Korean Academy of Prosthodontics (JKAP) for a 5-year period. Materials and methods: Of 336 articles in the JKAP published from 2006 to 2010, 255 articles using statistics were reviewed and classified by statistical method and year. The frequency and types of the statistical methods were examined, and the statistical errors were evaluated by the appropriateness of the experimental design, assumption check, independent outcomes, proper sample size and suitable use of statistical method. Statistical guidelines were completed based on the appropriateness. Results: Of the 255 articles using statistics, 193 articles (75.9%) used inferential statistics and 153 articles used SPSS statistical software (60.0%). Of the articles using inferential statistics, the three most frequently used statistical methods were ANOVA (41.5%), t-test (20.0%), and the nonparametric method (16.9%). The average rate of statistical errors was 61.2 percent, similar to the rate reported by several studies completed for the medical journal. Conclusion: After the whole analysis of the difference among the groups, post-hoc tests for the pairwise comparisons are required. The optimal sample size calculation is an essential part of this study protocol. To minimize the occurrence of statistical errors, statistical guidelines were developed according to each statistical test procedure and will contribute to the academic improvement in the JKAP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1296-1303
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• 2014

This study was conducted to develop predictive models for the growth of Bacillus cereus on carrot treated with slightly acidic electrolyzed water (SAcEW) and ultrasonication (US) at different storage temperatures. In addition, the inactivation of B. cereus by US with SAcEW was investigated. US treatment with a frequency of 40 kHz and an acoustic energy density of 400 W/L at $40^{\circ}C$ for 3 min showed the maximum reduction of 2.87 log CFU/g B. cereus on carrot, while combined treatment of US (400 W/L, $40^{\circ}C$, 3 min) with SAcEW reached to 3.1 log CFU/g reduction. Growth data of B. cereus on carrot treated with SAcEW and US at different temperatures (4, 10, 15, 20, 25, 30, and $35^{\circ}C$) were collected and used to develop predictive models. The modified Gompertz model was found to be more suitable to describe the growth data. The specific growth rate (SGR) and lag time (LT) obtained from the modified Gompertz model were employed to establish the secondary models. The newly developed secondary models were validated using the root mean square error, bias factor, and accuracy factor. All results of these factors were in the acceptable range of values. After compared SGR and LT of B. cereus on carrot, the results showed that the growth of B. cereus on carrot treated with SAcEW and US was slower than that of single treatment. This result indicates that shelf life of carrot treated with SAcEW and US could be extended. The developed predictive models might also be used to assess the microbiological risk of B. cereus infection in carrot treated with SAcEW and US.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1181-1188
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• 2014

This study investigated the quality characteristics and antioxidant activities of Yukwa added with 'Donganme' sorghum bran powder and its extracts. 'Donganme' variety has the highest antioxidant activity among sorghum varieties in Korea. The added contents of sorghum bran to Yukwa were 1% and 5% bran powder of 'Donganme' (BPD 1% and 5%) as well as 0.1%, 0.5%, and 1% bran powder extracts of 'Donganme' (BED 0.1%, 0.5%, and 1%). The contents of protein, ash, and minerals of BPD 1% and 5% added Yukwa were higher compared to non-added and BED 0.1%, 0.5%, and 1% added Yukwa. The contents of flavonoids of BPD 1% and 5% as well as BED 0.1%, 0.5%, and 1% added Yukwa increased by 1.6~17.1 fold, and DPPH and ABTS radical scavenging activities increased by 1.8~7.4 fold and 2.3~13.6 fold, respectively, compared to non-added Yukwa. Yukwa added with BED 1% showed the highest antioxidant activity among the treatments, followed by BPD 5%, BED 0.5%, BPD 1%, and BED 0.1% added Yukwa. The expansion ratios of BPD 5% and BED 1% added Yukwa remarkably decreased compared to those of non-added and other treatments. The sensory evaluation values corroborated the results of the Yukwa expansion ratio. The acid values of Yukwa under high temperature storage ($60{\pm}1^{\circ}C$) increased rapidly after 20 days in all treatments, and those of BPD 5% and 1% added Yukwa increased slowly compared to non-added Yukwa. ABTS radical scavenging activities of Yukwa showed little change during storage in all treatments. As a results, addition of sorghum bran below BPD 1% and BED 0.5% was suitable for antioxidant activity, quality characteristics and sensory evaluation.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.2
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• pp.207-220
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• 2006

The newly developed equipments for the early detection of carious lesion are LFD (laser fluorescence device), Ultrasonic diagnostic system, CLSM(confocal laser scanning microscopy), QLF(quantitative light-induced fluorescence) and DIFOTI (digital imaging fiber-optic trans-illumination) system. In this study, DIFOTI system and LFD were used for the detection of early enamel caries. Twenty five primary teeth extracted from twenty one children at around the dentitional exchanging period were selected as samples. The results obtained from DIFOTI imaging and LFD measurement were compared with those of CLSM and comprehensive evaluations were made for the diagnostic capacity of each device. In vitro test, 40 sample teeth with their buccal & lingual surface formed by a window of $2{\times}3mm$ in diameter were immersed in artificial demineralizing solution for the period of 4, 8, 12 and 16 days. The results obtained from the experimental groups (DIFOTI, LFD) were compared to control group (CLSM) and we have reached to the following conclusions. 1. The sensitivity and specificity of DIFOTI system operated in oral environment was 88.2% and 76.9% respectively. 2. The sensitivity and specificity of LFD measured in oral environment was 76.5% and 69.2% respectively. 3, Regression analysis on the light transparent rate of DIFOTI showed its decrease according to the length of primary enamel decalcification performed in vitro(r=-0.96, p<0.05). 4. No statistically significant difference between LFT measurement and the length of in vitro decalcification was found in regression analysis (p>0.05). 5. The correlation coefficient of DIFOTI image transparent rate and the lesion depth of CLMS was -0.6988 (p<0.05), whereas no statistically significant difference was found for LFD measurement.

• Tuberculosis and Respiratory Diseases
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• v.41 no.6
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• pp.632-643
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• 1994

Background: The objective responses of cisplatin and etoposide (PVP) combination chemotherapy as second-line therapy following CAV was high (40~50%) and, in several reports, PVP yields survival results that are at least as good as those obtained with cyclophosphamide or doxorubicin-based regimens and with less host-related toxicity in chemotherapy-naive patients. We conducted a phase II study to evaluate the effect of a combination of cisplatin and etoposide as a fitst-line therapy in patients with small cell lung cancer. Methods: Sixty-one previously untreated small cell lung cancer patients with measurable lesion (s) received cisplatin(30 $mg/m^2$ IV, day 1~3) and etoposide(100 $mg/m^2$ IV, day 1~3). In patients with limited disease, after completion of 6 cycles of PVP chemotherapy, chest and prophylatic brain irradiation was performed in case of complete responder, chest irradiation on1y in partial responder. Results: 1) Of 55 evaluable patients, 13(24%) had a complete response and 29(53%) had a partial response. 2) The median survival time was 55.8 weeks for all patients(N=55), 61.1 weeks for limited disease(N=31), 51.3 weeks for extensive disease(N=24). 3) The response duration was 29.1 weeks for responders(N=42). 4) There was no significant prognostic factors influencing response rates. 5) The toxicity was tolerable and there was no treatment-related deaths. Conclusion: The PVP combination chemotherapy as a first-line therapy was effective and well-tolerated in patients with small cell lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.189-197
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• 2000

Background : Tissue inhibitor of metalloproteinase is a natural inhibitor that counteracts pro teolytic enzymes essential to the invasion of cancer cell. Whether or not TIMP-2 gene transfer via adenovirus could inhibit the invasion of lung cancer cell iη vitro was evaluated for the future purpose of gene therapy against lung cancer. Methods : Recombinant adenovirus-TIMP-2(Ad-TIMP-2) was generated by homologous recombination after pACCMV-TIMP-2 and pJM17 were cotransfected into 293 cell by standard calcium phosphate coprecipitate method. Calu-6, one of the most invasive lung cancer cells, was transduced with Ad-TIMP-2 or Ad-$\beta$gal. Anchorage-independent growth and invasiveness were assessed by soft agar clonogenicity assay and invasion assay using two-chamber, well divided by matrigel. Results : Ad-TIMP-2 transduced calu-6 cells produced biologically active TIMP-2 more than 50 times more than parental calu-6. TIMP-2 gene transfer did not suppress the in vitro tumorigenicity. However, two chamber well assay revealed that Ad-TIMP-2 transduction reduced the invasiveness of calu-6 efficiently (12% compared with parental cell) even at low 10moi. Conclusion : Even though TIMP-2 gene transfer did not inhibit in vitro tumorigenicity, it did inhibit invasion of lung cancer cell in vitro. The inhibition of invasion by Ad-TIMP-2 may be a useful strategy for the treatment of lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.55 no.4
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• pp.388-394
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• 2003

Background : Monoclonal antibodies directed against well-known epitopes on cytokeratin (CK) 8, 18 and 19 (Monototal) have been used in the development of a new diagnostic tool for lung cancer. In the mid-1990s, CK 19 fragments (Cyfra 21-1) became popular and widely used for such diagnosis. This is the first study specifically designed to compare these two markers. Method : The serum levels of CK 8, 18 and 19 were measured using two-site monoclonal/polyclonal immunoradiometric assay kit in 57 healthy adults and 289 patients who were admitted to Seoul National University Hospital from May to September, 2002. The lung cancer group comprised 129 primary lung cancer patients; 116 with non-small cell lung cancer(NSCLC) and 13 with small cell lung cancer (SCLC). The control group comprised 160 non-malignant pulmonary lung disease patients and 57 healthy adults. A total of 166 twin Monototal and Cyfra 21-1 serum assays were obtained; 76 with lung cancer, 70 with non-malignant pulmonary lung disease and 20 healthy adults. Results : The mean serum value of Monototal was $412.47{\pm}455.45U/L$ in NSCLC, $237.08{\pm}145.15U/L$ in SCLC, $126.54{\pm}95.72U/L$ in non-malignant pulmonary lung disease, and $63.68{\pm}31.66U/L$ in healthy adults. The serum values of the lung cancer groups were significantly higher than those of the control group (p<0.01). Using a cut off value of 188U/L, sensitivity and specificity was 66.4% and 81.9% in NSCLC, and 43.8% and 81.9% in SCLC, respectively. The serum levels of CK 8, 18 and 19 were higher in advanced NSCLC than in early stage disease. Conclusion : The serum levels of CK 8, 18 and 19 may be useful in the diagnosis of NSCLC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1137.2-1245
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• 2001

The ${\gamma}$-irradiated medicinal herbs were examined the genotoxicological safety to consider the possibility of application of the irradiation technology for hygienic purpose. The three medicinal herbs -Glycyrrhigae Radix, Aurantii nobilis Pericarpium and Bupleuri Radix- were irradiated with ${\gamma}$ -rays at the practical dosage of 10 kGy. The hot water extracts of the irradiated herbs were examined in two short-term in vitro tests: (1) Ames test in Salmonella typhimurium TA98 and TA100, (2) Micronucleus test in cultured Chinese hamster ovary(CHO) cells. In the Salmonella reversion assays both with and without metabolic activation, the number of revertant colonies was not increased with each extract from the irradiated herbs, compared with negative controls. No significant difference in formation of the colonies was observed between non-irradiated and 10 kGy-irradiated herbs. These results indicated that no mutagenicity of the irradiated herbs was detected. In the micronucleus tests in cultured CHO cells, the incidences of micronucleus were not increased with irradiated herbs, and no significant difference in the incidences was observed between non-irradiated and irradiated herbs. These results indicated that no cytogenetic toxicity of the irradiated herbs was detected. The results of the two in vitro tests suggest that the irradiated herbs do not show mutagenic effects and cytogenetic toxicity. Further tests of in vivo genotoxicity and chronic toxicity are needed to determine the safety of the herbs irradiated with ${\gamma}$ -rays at practical doses.

• Tuberculosis and Respiratory Diseases
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• v.63 no.5
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• pp.405-411
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• 2007

Background: The objective of this study was to evaluate the clinical applicability of the repeatability criteria recommended by the American Thoracic Society/European Respiratory Society (ATS/ERS) spirometry guidelines and to determine which factors affect the repeatability of spirometry in Korean adults. Methods: We reviewed the spirometry data of 4,663 Korean adults from the Korean National Health and Nutritional Examination Survey (KNHANES) Chronic Obstructive Pulmonary Disease Cohort (COPD cohort) and the Community-based Cohort Study VI-Fishing village/Islands (community cohort). We measured the anthropometric factors and differences between the highest and second-highest FVC (dFVC) and $FEV_1$ ($dFEV_1$) from prebronchodilator spirometry. Analyses included the distribution of dFVC and $dFEV_1$, comparison of the values meeting the 1994 ATS repeatability criteria with the values meeting the 2005 ATS/ERS repeatability criteria, and the performance of linear regression for evaluating the influence of subject characteristics and the change of criteria on the spiro-metric variability. Results: About 95% of subjects were able to reproduce FVC and $FEV_1$ within 150 ml. The KNHANES based on the 1994 ATS guidelines showed poorer repeatability than the COPD cohort and community cohort based on the 2005 ATS/ERS guidelines. Demographic and anthropometric factors had little effect on repeatability, explaining only 0.5 to 3%. Conclusion: We conclude that the new spirometry repeatability criteria recommended by the 2005 ATS/ERS guidelines is also applicable to Korean adults. The repeatability of spirometry depends little on individual characteristics when an experienced technician performs testing. Therefore, we suggest that sustained efforts for public awareness of new repeatability criteria, quality control of spirograms, and education of personnel are needed for reliable spirometric results.

• Journal of Intelligence and Information Systems
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• v.20 no.2
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• pp.149-162
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• 2014

Course guidance is a mentoring process which is performed before students register for coming classes. The course guidance plays a very important role to students in checking degree audits of students and mentoring classes which will be taken in coming semester. Also, it is intimately involved with a graduation assessment or a completion of ABEEK certification. Currently, course guidance is manually performed by some advisers at most of universities in Korea because they have no electronic systems for the course guidance. By the lack of the systems, the advisers should analyze each degree audit of students and curriculum information of their own departments. This process often causes the human error during the course guidance process due to the complexity of the process. The electronic system thus is essential to avoid the human error for the course guidance. If the relation data model-based system is applied to the mentoring process, then the problems in manual way can be solved. However, the relational data model-based systems have some limitations. Curriculums of a department and certification systems can be changed depending on a new policy of a university or surrounding environments. If the curriculums and the systems are changed, a scheme of the existing system should be changed in accordance with the variations. It is also not sufficient to provide semantic search due to the difficulty of extracting semantic relationships between subjects. In this paper, we model a course mentoring ontology based on the analysis of a curriculum of computer science department, a structure of degree audit, and ABEEK certification. Ontology-based course guidance system is also proposed to overcome the limitation of the existing methods and to provide the effectiveness of course mentoring process for both of advisors and students. In the proposed system, all data of the system consists of ontology instances. To create ontology instances, ontology population module is developed by using JENA framework which is for building semantic web and linked data applications. In the ontology population module, the mapping rules to connect parts of degree audit to certain parts of course mentoring ontology are designed. All ontology instances are generated based on degree audits of students who participate in course mentoring test. The generated instances are saved to JENA TDB as a triple repository after an inference process using JENA inference engine. A user interface for course guidance is implemented by using Java and JENA framework. Once a advisor or a student input student's information such as student name and student number at an information request form in user interface, the proposed system provides mentoring results based on a degree audit of current student and rules to check scores for each part of a curriculum such as special cultural subject, major subject, and MSC subject containing math and basic science. Recall and precision are used to evaluate the performance of the proposed system. The recall is used to check that the proposed system retrieves all relevant subjects. The precision is used to check whether the retrieved subjects are relevant to the mentoring results. An officer of computer science department attends the verification on the results derived from the proposed system. Experimental results using real data of the participating students show that the proposed course guidance system based on course mentoring ontology provides correct course mentoring results to students at all times. Advisors can also reduce their time cost to analyze a degree audit of corresponding student and to calculate each score for the each part. As a result, the proposed system based on ontology techniques solves the difficulty of mentoring methods in manual way and the proposed system derive correct mentoring results as human conduct.