• Title/Summary/Keyword: Evaluation-Methods

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Environmental Damage to Nearby Crops by Hydrogen Fluoride Accident (불화수소 누출사고 사례를 통한 주변 농작물의 환경피해)

  • Kim, Jae-Young;Lee, Eunbyul;Lee, Myeong Ji
    • Korean Journal of Environmental Agriculture
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    • v.38 no.1
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    • pp.54-60
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    • 2019
  • BACKGROUND: Hydrogen fluoride is one of the 97 accident preparedness substances regulated by the Ministry of Environment (Republic of Korea) and chemical accidents should be managed centrally due to continual occurrence. Especially, hydrogen fluoride has a characteristic of rapid diffusion and very toxic when leaking into the environment. Therefore, it is important to predict the impact range quickly and to evaluate the residual contamination immediately to minimize the human and environmental damages. METHODS AND RESULTS: In order to estimate the accident impact range, the off-site consequence analysis (OCA) was performed to the worst and alternative scenarios. Also, in order to evaluate the residual contamination of hydrogen fluoride in crop, the samples in accident site were collected from 15-divided regions (East direction from accident sites based on the main wind direction), and the concentration was measured by fluoride ($F^-$) ion-selective electrode potentiometer (ISE). As a result of the OCA, the affected distance by the worst scenario was estimated to be >10 km from the accident site and the range by the alternative scenario was estimated to be about 1.9 km. The residual contamination of hydrogen fluoride was highest in the samples near the site of the accident (E-1, 276.82 mg/kg) and tended to decrease as it moved eastward. Meanwhile, the concentrations from SE and NE (4.96~28.98 mg/kg) tended to be lower than the samples near the accident site. As a result, the concentration of hydrogen fluoride was reduced to a low concentration within 2 km from the accident site (<5 mg/kg), and the actual damage range was estimated to be around 2.2 km. Therefore, it is suggested that the results are similar to those of alternative accident scenarios calculated by OCA (about 1.9 km). CONCLUSION: It is difficult to estimate the chemical accident-affecting range/region by the OCA evaluation, because it is not possible to input all physicochemical parameters. However simultaneous measurement of the residual contamination in the environment will be very helpful in determining the diffusion range of actual chemical accident.

Evaluation of static fracture resistances and patterns of pulpless tooth restored with poly-ether-ketone-ketone (PEKK) post (Poly-ether-ketone-ketone (PEKK) 포스트로 수복한 근관 치료 치아의 정적 파절 저항성 및 파절 형태에 관한 평가)

  • Park, Ha Eun;Lee, Cheol Won;Lee, Won Sup;Yang, Sung Eun;Lee, Su Young
    • The Journal of Korean Academy of Prosthodontics
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    • v.57 no.2
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    • pp.127-133
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    • 2019
  • Purpose: The purpose of present study was to investigate fracture strength and mode of failure of endodontically treated teeth restored with metal cast post-core system, prefabricated fiber post system, and newly introduced polyetherketoneketone (PEKK) post-core system. Materials and methods: A total of 21 mandibular premolar were randomly grouped into 3 groups of 7 each according to the post material. Group A was for metal cast post core; Group B for prefabricated glass fiber post and resin core; and Group C for milled PEKK post cores. All specimens were restored with metal crown. The fracture strength of each specimen was measured by applying a static load of 135-degree to the tooth at 2 mm/min crosshead speed using a universal testing machine. After the fracture strength measurement, the mode of failure was observed. The results were analyzed using Kruscal-Wallis test and post hoc Mann-Whitney U test at confidence interval ${\alpha}=.05$. Results: Fracture resistance of PEKK post core was lower than those of cast metal post and fiber reinforced post with composite resin core. In the aspect of fracture mode most of the root fracture occurred in the metal post core, whereas the post detachment occurred mainly in the fiber reinforced post. In the case of PEKK post core, teeth and post were fractured together. Conclusion: It is necessary to select appropriate materials of post for extensively damaged teeth restoration and clinical application of the PEKK post seems to require more research on improvement of strength.

Analysis of esthetic factors and evaluation of esthetic perception for maxillary anteriors of dental students (치과대학생의 상악 전치부의 심미적 요소 분석 및 인식도 평가)

  • Kim, Seon-Kyung;Kim, Ok-Su
    • The Journal of Korean Academy of Prosthodontics
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    • v.57 no.2
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    • pp.118-126
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    • 2019
  • Purpose: This research is to investigate factors that affect dental aesthetics and analyze whether individual perception affects and difference of genders affects the esthetic factors. Materials and methods: Seventy dental students of Chonnam University aged from 25 to 35 years old without periodontal problems were included. Maxillary dental cast for participants were made, and standardized photo was taken with a digital camera. Maximum visual width and the position of gingival zenith of maxillary anterior teeth and maximum height of the maxillary central incisors were measured by a measurement program and the shape of central incisor was categorized. Questionnaire was conducted to evaluate esthetic perception. SPSS program was used to perform statistical analysis. Results: The average visual width ratio of right maxillary anteriors was 1.38:1:0.78 and 1.41:1:0.81 for the left which differ from the golden ratio. The width to height ratio for right and left central incisor was 0.84 and 0.83 respectively. The gingival zenith position was determined to be: mostly, central incisors and canines were located in the distal side, lateral incisors were located in the center. The visual width ratio of right maxillary anterior teeth, ratio of width to height of central incisor, gingival zenith position, crown morphology and amounts of gingival exposure upon smiling were not significantly different between genders, and facial patterns and these dental esthetic factors were not related to aesthetic perception. Conclusion: Even though participants had the visual width ratio of maxillary anteriors or ideal width to ideal height of central incisors that did not agree with the golden ratio, they had high satisfaction for dental esthetics. Esthetic perception depends more on subjective judgements of participants than objective indices.

Comparison of the accuracy of intraoral scanner by three-dimensional analysis in single and 3-unit bridge abutment model: In vitro study (단일 수복물과 3본 고정성 수복물 지대치 모델에서 삼차원 분석을 통한 구강 스캐너의 정확도 비교)

  • Huang, Mei-Yang;Son, Keunbada;Lee, Wan-Sun;Lee, Kyu-Bok
    • The Journal of Korean Academy of Prosthodontics
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    • v.57 no.2
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    • pp.102-109
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    • 2019
  • Purpose: The purpose of this study was to evaluate the accuracy of three types of intraoral scanners and the accuracy of the single abutment and bridge abutment model. Materials and methods: In this study, a single abutment, and a bridge abutment with missing first molar was fabricated and set as the reference model. The reference model was scanned with an industrial three-dimensional scanner and set as reference scan data. The reference model was scanned five times using the three intraoral scanners (CS3600, CS3500, and EZIS PO). This was set as the evaluation scan data. In the three-dimensional analysis (Geomagic control X), the divided abutment region was selected and analyzed to verify the scan accuracy of the abutment. Statistical analysis was performed using SPSS software (${\alpha}=.05$). The accuracy of intraoral scanners was compared using the Kruskal-Wallis test and post-test was performed using the Pairwise test. The accuracy difference between the single abutment model and the bridge abutment model was analyzed by the Mann-Whitney U test. Results: The accuracy according to the intraoral scanner was significantly different (P < .05). The trueness of the single abutment model and the bridge abutment model showed a statistically significant difference and showed better trueness in the single abutment (P < .05). There was no significant difference in the precision (P = .616). Conclusion: As a result of comparing the accuracy of single and bridge abutments, the error of abutment scan increased with increasing scan area, and the accuracy of bridge abutment model was clinically acceptable in three types of intraoral scanners.

Survival in clinical stage I endometrial cancer with single vs. multiple positive pelvic nodes: results of a multi-institutional Italian study

  • Uccella, Stefano;Falcone, Francesca;Greggi, Stefano;Fanfani, Francesco;De Iaco, Pierandrea;Corrado, Giacomo;Ceccaroni, Marcello;Mandato, Vincenzo Dario;Bogliolo, Stefano;Casarin, Jvan;Monterossi, Giorgia;Pinelli, Ciro;Mangili, Giorgia;Cormio, Gennaro;Roviglione, Giovanni;Bergamini, Alice;Pesci, Anna;Frigerio, Luigi;Uccella, Silvia;Vizza, Enrico;Scambia, Giovanni;Ghezzi, Fabio
    • Journal of Gynecologic Oncology
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    • v.29 no.6
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    • pp.100.1-100.13
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    • 2018
  • Objective: To investigate survival outcomes in endometrioid endometrial cancer (EEC) patients with single vs. multiple positive pelvic lymph nodes. Methods: We performed a retrospective evaluation of all consecutive patients with histologically proven International Federation of Gynecology and Obstetrics (FIGO) stage IIIC1 EEC who underwent primary surgical treatment between 2004 and 2014 at seven Italian gynecologic oncology referral centers. Patients with pre- or intra-operative evidence of extra-uterine disease (including the presence of bulky nodes) and patients with stage IIIC2 disease were excluded, in order to obtain a homogeneous population. Results: Overall 140 patients met the inclusion criteria. The presence of >1 metastatic pelvic node was significantly associated with an increased risk of recurrence and mortality, compared to only 1 metastatic node, at both univariate (recurrence: hazard ratio [HR]=2.19; 95% confidence interval [CI]=1.2-3.99; p=0.01; mortality: HR=2.8; 95% CI=1.24-6.29; p=0.01) and multivariable analysis (recurrence: HR=1.91; 95% CI=1.02-3.56; p=0.04; mortality: HR=2.62; 95% CI=1.13-6.05; p=0.02) and it was the only independent predictor of prognosis in this subset of patients. Disease-free survival (DFS) and disease-specific survival (DSS) were significantly longer in patients with only 1 metastatic node compared to those with more than 1 metastatic node (p=0.008 and 0.009, respectively). Conclusion: The presence of multiple metastatic nodes in stage IIIC1 EEC represents an independent predictor of worse survival, compared to only one positive node. Our data suggest that EEC patients may be categorized according to the number of positive nodes.

Evaluation of sleep quality and stress response in patients requiring dental prosthetic treatment (치과보철치료를 요하는 환자에서의 수면질과 스트레스 반응 평가)

  • Jeon, Hye-Mi;Jung, Kyoung-Hwa;Choi, Na-Rae;Song, Jae-Min;Lee, So-Hyoun;Kim, So-Yeun
    • The Journal of Korean Academy of Prosthodontics
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    • v.59 no.2
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    • pp.181-189
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    • 2021
  • Purpose: The purpose of this study is to investigate the stress response and sleep state of the new patients who visit the hospital for prosthodontic treatment due to tooth loss to make reference to further treatment direction. Materials and methods: Examinations, consultations, and surveys were conducted on 236 patients (94 males, 142 females, and 24-86 years old), who newly registered at the department of prosthodontics at Pusan national university hospital, for 2 years from 2018. The number of remaining teeth, edentulous arch, possibility of mastication, and future prosthetic treatment directions were recorded. The visual analogue scale (VAS), stress response inventory (SRI) and Insomnia severity index (ISI) were used as tools to measure patient's subjective discomfort, stress response, and sleep status. Results: Among the entire prosthodontic patient group, the average value of 'fatigue' was significantly higher among the 7 items of SRI, and the value of 'aggression' was significantly lower (P<.001). There are a significant difference between the edentulous and full dentition in the oral discomfort value measured by VAS (P=.004). In cases where less than 20 teeth remain, mastication is impossible, and patients who are planning treatment with removable prostheses, VAS value and 'depression' and 'fatigue' values in SRI were higher than those in the reverse case (P<.05). The patients showed severe level in VAS value have high value of 'tension', 'somatization', 'depression', 'fatigue'and 'frustration'in SRI than non-serious patients (P<.05). Clinical insomnia occurred in 11.4% of all patients, and women had significantly lower sleep quality than men (P=.044). Patients with insomnia showed significantly higher scores on the VAS value and all 7 SRI items than those of normal sleepers (P<.05). Conclusion: The new prosthetics had high 'fatigue' value among the 7 items of SRI. The oral condition, number of residual teeth and mastication function and clinical insomnia affected oral discomfort and the stress response.

Herbal Medicine for the Treatment of Rosacea: A Systematic Review and Meta-analysis of Randomized Controlled Trials (주사(Rosacea)의 한약 치료에 대한 체계적 문헌고찰 및 메타분석)

  • Kang, Eun-Jeong;Kam, Eun-Young;Kim, Seo-Hee;Yoon, Seok-Yeong;Jeon, Seok-Hee;Choi, Jung-Wha;Kim, Jong-Han;Park, Soo-Yeon;Jung, Min-Yeong
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.34 no.3
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    • pp.27-54
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    • 2021
  • Objectives : This review was conducted to validate the effectiveness and safety of herbal medicine combined with conventional therapy for rosacea. Methods : Randomized controlled trials(RCTs) reporting the effects of herbal medicine treatment on rosacea were searched through eight electronic databases from 2016 to March 17, 2020. This study collection and data extraction were performed by two independent reviews. The Cochrane risk-of-bias tool was used for the evaluation of the risk of bias in all included RCTs. Mean differences(MD) and Risk ratio(RR) of 95% Confidence intervals(Cls) were calculated and data synthesis was conducted using Review Manager(RevMan, ver.5.4) Results : Eighteen RCTs were included and all trials compared the combined therapy of herbal medicine with conventional western therapy to conventional therapy alone. The effective rate of the combination of herbal medicine with western medicine(RR 1.20, 95% CI : 1.13-1.28, p<0.00001, I2=0%), the effective rate of the combination of herbal medicine with laser-based therapy(RR 1.12, 95% CI : 1.04-1.21, p=0.004, I2=18%) and the effective rate of the combination treatment group using herbal medicine, western medicine and external drugs were all statistically higher that of the control group(RR 1.19, 95% CI : 1.11-1.28, p<0.00001, I2=0%). The score of non transient erythema(MD -0.36, 95% CI : -1.01 0.29, p=0.27, I2=93%), flushing(MD -0.69, 95% CI : -0.97, 0.41, p<0.00001, I2=32%), papules or pustules(MD 0.10, 95% CI : -0.15, 0.35 p=0.44, I2=0%) were also seen in the herbal medicine and western medicine combination group. The overall risk of bias of the included studies was some concerns. No serious adverse effects were observed. Conclusions : This review found the safety and effectiveness of the combined therapy of herbal medicine with conventional western therapy for rosacea.

A Study on the Development of Middle School History Curriculum Standards for Revitalization of Cultural Property Education (문화재 교육 활성화를 위한 중학교 역사교육과정기준 개발 방안 연구)

  • AHN, Daehyun;HONG, Hoojo
    • Korean Journal of Heritage: History & Science
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    • v.54 no.3
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    • pp.150-167
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    • 2021
  • Since the advent of tertiary curriculum, middle school history education has been focused on political history, but many students perceive history as a simple memorization subject and complain about difficulties in abstract learning. The researcher saw this problem as caused by the history curriculum, and carried out this study for the purpose of proposing a revitalization of cultural property education in the middle school history curriculum. First, through the analysis of prior research, the usefulness of cultural property education, such as nurturing creative talent and realizing interactive history classes, was revealed, and the problems of the current political history-centered middle school history curriculum were pointed out. Afterwards, as a result of conducting an opinion survey on middle school 3rd grade students and social studies teachers, it was found that first, both middle school students and their teachers thought that the current political history-centered history had much room for improvement. Second, all groups agreed on the necessity of cultural property education in history education. However, in reality, it was found that it was not easy to sufficiently educate students about cultural property in a political history-centered curriculum. Third, teachers thought that it was necessary to improve the current history curriculum in order to enhance cultural property education. Based on these findings, the researcher suggested an improvement plan for the 2015 revised history curriculum. First, in the 'nature of the subject' section, cultural properties and historical materials should be included, and in the 'objective' section, politics, economy, society, and culture should be included. Contents related to cultural properties should be added to the sub-themes in the 'content system and achievement standards', and cultural properties-related contents should be further reinforced in the achievement standards, 'teaching, learning and evaluation'. It was suggested that this section should include cultural property learning and historical material learning, and guidance on teaching and learning methods of cultural property education should be added. If these aspects are reflected in the 2022 revised curriculum that is currently being developed, cultural property education will be improved, and more lively history education will be provided to students.

Evaluation of diet quality according to the eating-out patterns of preschoolers and school-aged children in South Korea: based on data from the 2016-2018 Korea National Health and Nutrition Examination Survey (우리나라 유아 및 학령기 아동의 외식패턴에 따른 식사의 질 평가: 2016-2018 국민건강영양조사 자료 활용)

  • Ju, Yu-na;Lee, Youngmi;Song, Kyunghee;Lee, Yujin
    • Journal of Nutrition and Health
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    • v.54 no.2
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    • pp.165-178
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    • 2021
  • Purpose: This study examined the eating-out patterns of Korean infants and school-aged children and compared diet quality. Methods: Data were obtained from the 2016-2018 Korea National Health and Nutrition Examination Survey. The subjects were 306 children aged 3 to 11 years old that ate dinner at restaurants. Percentage energy intakes of 24 food groups were calculated, and cluster analysis was used to identify eating-out patterns. Diet quality was assessed by calculating percentage energy and nutrient intakes using one-third of the 2015 Dietary Reference Intakes for Korean (KDRIs), nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and index of nutritional quality (INQ). Results: Cluster analysis identified 2 eating-out patterns, that is, a 'rice-centered' (53%) and a 'mixed diet' (47%) pattern. For those with the mixed diet pattern, ratios of carbohydrates, protein, and fat to total calories were 48:20:31, whereas for the rice-centered pattern, ratios were 62:15:21 (p < 0.001). Intakes of energy and most nutrients in the mixed diet pattern were excessive, but the intakes of the most nutrients in the rice-centered pattern were much lower than their KDRIs. MARs were higher for the mixed diet pattern than the rice-centered pattern (0.74 vs. 0.66) (p < 0.001), and INQs for vitamin C (p = 0.007) and calcium (p = 0.018) were lower for the rice-centered pattern, whereas INQ for iron (p = 0.003) was lower for the mixed diet pattern. Conclusion: The quality of meals for infants and school-aged children depended on eating-out patterns, but the rice-centered and mixed diet patterns both failed to provide an appropriately balanced meal pattern. The results of this study suggest that healthy menus need to be developed for children in restaurants.

Evaluation of the possibility of clinical application by surface dose measurement of ViewRay in MFW treatment (MFW 치료 시 ViewRay의 표면선량 측정에 따른 임상 적용 가능성 평가)

  • Sun, Geo Jun;Son, Sang Jun;Lee, Yang Hoon;Lee, Je Hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.169-176
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    • 2018
  • Purpose : The purpose of this study is to evaluate clinical applicability of Co-60 ViewRay treatment plan to increase the skin dose in case of high skin dose is required such as Malignant Fungating Wound By measuring the presence / absence of Bolus application and skin dose by the treatment device and comparing it Materials and Methods : Nine inner measuring points of 2.5 cm lattice arrangement and all 13 measuring points including upper and lower left and right measuring points touching the chest and skin were marked. After CT was taken, each treatment plan was formulated through Eclipse and ViewRay-TPS, and a Fixed beam-IMRT treatment plan was formulated so that the left chest V2Gy=95 % is delivered. Before measurement QED detector was calibrated and the QED detector was positioned at the 13 measurement points displayed on Phantom and surface dose of each treatment planner was measured using 5 mm Bolus application using True-beam and View-ray before and after, measure three times and compare each before applying 5 mm Bolus. Results : The surface dose of the Co-60 ViewRay and the linear accelerator appeared at $76.8%{\pm}5.2%$ vs. $67.3{\pm}%7.5%$ and the surface dose after application of 5 mm Bolus was $87.6%{\pm}8.9%$ vs. $80.3%{\pm}10.2%$ It was measured at 10.2 % (p<0.001). Conclusion : As a result of the surface dose measurement of each treatment instrument, Co-60 ViewRay confirmed that the surface dose reached 95.6 % of 6 MV Linac with conventional 5 mm bolus, despite not using Bolus (p<0.001). Also, by utilizing magnetic resonance images for each treatment, it is possible to observe the change in the treatment site without the problem of exposure, it is easy to formulate an adaptive treatment plan and it is easy to secure the skin dose, so the size In the case of Malignant Fungating Wound patients who need fast skin changes and need high skin doses, Co-60 ViewRay is considered to be more useful than linear accelerators.

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