• Journal of Advanced Navigation Technology
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• v.28 no.1
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• pp.44-50
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• 2024

This study analyzed the effect of flight stress on job satisfaction and safety culture on 193 domestic civil airline pilots. As a result of the analysis, flight stress had a negative effect on job satisfaction, and pilots with low job satisfaction had a low awareness of safety culture. In particular, there was a difference in the effect of flight stress on job satisfaction and safety culture according to the airlines and rank of pilots. This suggests the necessity of developing customized stress management programs for each airline and pilot position. The study emphasizes the importance of managing pilots' stress and improving job satisfaction to reinforce the safety culture of the aviation industry. In addition, airlines should develop strategies to strengthen safety culture by reducing pilot stress and increasing job satisfaction. The result of this study is to be used as useful basic data for finding ways to manage pilots' stress and strengthen safety culture in the aviation industry.

• Imaging Science in Dentistry
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• v.54 no.2
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• pp.181-190
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• 2024

Purpose: This study compared sequential changes in skeletal stability and the pharyngeal airway following mandibular setback surgery involving fixation with either a titanium or a bioabsorbable plate and screws. Materials and Methods: Twenty-eight patients with mandibular prognathism undergoing bilateral sagittal split osteotomy by titanium or bioabsorbable fixation were randomly selected in this study. Lateral cephalometric analysis was conducted preoperatively and at 1 week, 3-6 months, and 1 year postoperatively. Mandibular stability was assessed by examining horizontal (BX), vertical (BY), and angular measurements including the sella-nasion to point B angle and the mandibular plane angle (MPA). Pharyngeal airway changes were evaluated by analyzing the nasopharynx, uvula-pharynx, tongue-pharynx, and epiglottis-pharynx (EOP) distances. Mandibular and pharyngeal airway changes were examined sequentially. To evaluate postoperative changes within groups, the Wilcoxon signed-rank test was employed, while the Mann-Whitney U test was used for between-group comparisons. Immediate postoperative changes in the airway were correlated to surgical movements using the Spearman rank test. Results: Significant changes in the MPA were observed in both the titanium and bioabsorbable groups at 3-6 months post-surgery, with significance persisting in the bioabsorbable group at 1 year postoperatively (2.29°±2.28°; P<0.05). The bioabsorbable group also exhibited significant EOP changes (-1.21±1.54 mm; P<0.05) at 3-6 months, which gradually returned to non-significant levels by 1 year postoperatively. Conclusion: Osteofixation using bioabsorbable plates and screws is comparable to that achieved with titanium in long-term skeletal stability and maintaining pharyngeal airway dimensions. However, a tendency for relapse exists, especially regarding the MPA.

• Dementia and Neurocognitive Disorders
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• v.21 no.4
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• pp.117-125
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• 2022

Background and Purpose: Medication adherence is essential for effective medical treatment. However, it is challenging for cognitively impaired patients. We investigated whether an automated telephone reminder service improves medication adherence and reduces the decline of cognitive function in isolated patients with cognitive impairment. Methods: This was a single-center, randomized clinical trial. We enrolled mild cognitive impairment (MCI) or Alzheimer's disease (AD) patients who lived alone or with a cognitively impaired spouse. We provided an automated telephone reminder service for taking medication to the intervention group for 6 months. The control group was provided with general guidelines for taking the medication every month. The participants underwent neuropsychological assessment at the beginning and end of the study. Statistical significance was tested using nonparametric Wilcoxon rank sum and Wilcoxon matched-pairs signed-rank tests. Results: Thirty participants were allocated randomly to groups, and data for 29 participants were analyzed. The mean age was 79.6 (standard deviation, 6.0) years and 79.3% of the participants were female. There was no significant difference in medication adherence between the 2 groups. However, a subgroup analysis among participants with more than 70% response rates showed better medication adherence compared to the control group (intervention: 94.6%; control: 90.2%, p=0.0478). There was no significant difference in the change in cognitive function between the 2 groups. Conclusions: If a patient's compliance is good, telephone reminders might be effective in improving medication adherence. It is necessary to develop reminder tools that can improve compliance for cognitively impaired patients.

• Imaging Science in Dentistry
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• v.54 no.3
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• pp.276-282
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• 2024

Purpose: This study aimed to assess the performance of 2-dimensional (2D) imaging with microscopy coils in delineating teeth and periodontal tissues compared with conventional 3-dimensional(3D) imaging on a 3 T magnetic resonance imaging (MRI) unit. Materials and Methods: Twelve healthy participants (4 men and 8 women; mean age: 25.6 years; range: 20-52 years) with no dental symptoms were included. The left mandibular first molars and surrounding periodontal tissues were examined using the following 2 sequences: 2D proton density-weighted (PDw) images and 3D enhanced T1 high-resolution isotropic volume excitation (eTHRIVE) images. Two-dimensional MRI images were taken using a 3 T MRI unit and a 47 mm microscopy coil, while 3D MRI imaging used a 3 T MRI unit and head-neck coil. Oral radiologists assessed dental and periodontal structures using a 4-point Likert scale. Inter- and intra-observer agreement was determined using the weighted kappa coefficient. The Wilcoxon signed-rank test was used to compare 2D-PDw and 3D-eTHRIVE images. Results: Qualitative analysis showed significantly better visualization scores for 2D-PDw imaging than for 3D-eTHRIVE imaging (Wilcoxon signed-rank test). 2D-PDw images provided improved visibility of the tooth, root dental pulp, periodontal ligament, lamina dura, coronal dental pulp, gingiva, and nutrient tract. Inter-observer reliability ranged from moderate agreement to almost perfect agreement, and intra-observer agreement was in a similar range. Conclusion: Two-dimensional-PDw images acquired using a 3 T MRI unit and microscopy coil effectively visualized nearly all aspects of teeth and periodontal tissues.

• Journal of Environmental Impact Assessment
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• v.24 no.3
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• pp.217-232
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• 2015

This study is to examine the section-based stream management with environmental characteristics and user monitoring. In Jeonjucheon, upstream section located near to Jeonju Hanok village has very good water quality and natural stream landscape. In case of mid/down streams, water quality is good and heavy concentration of facility leads to high use rates of these sections. The questionnaire consists of 5 parts: user characteristics, use behavior, citizen participation, importance rank, and Importance-Satisfaction(IS). 383 out of 454 responses with listwise deletion are used for demographic analysis and IS Analysis. In terms of citizen participation through 'ecological experience activity' and 'stream stewardship activity', 'occasional participation' shows the average of 78% in all three sections. For importance rank, the results arranged in order of priority show 'water quality' > 'green corridor' > 'trail' in up/down streams and 'water quality' > 'vegetation management' > 'trail' in midstream. Therefore, 'water quality' appears to be the most important variable among 13 variables. At last, the results of ISA indicate that all 10 variables need to be improved as satisfaction is lower than importance. In addition, 'plant management' variable falls into 'concentrate here' quadrant where importance is high and satisfaction is low.

• Journal of Hospice and Palliative Care
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• v.18 no.1
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• pp.51-59
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• 2015

Purpose: Predicting life expectancy of terminally ill cancer patients is very important. In many studies, ferritin is detected at higher levels in the sera of cancer patients, and higher ferritin level correlates with aggressiveness of disease and poor outcomes of patients. This study evaluated a prognostic role of serum ferritin levels in terminally ill cancer patients. Methods: This study enrolled 65 terminally ill cancer patients from March through June 2012. We assessed routine laboratory findings including serum ferritin levels as well as demographic and clinical characteristics of the patients. To examine the association between serum ferritin levels and patient's characteristics, we used Spearman's correlation analysis, Wilcoxon's rank sum test or Kruskal-Wallis test, as appropriately. For multivariate analysis, Cox's proportional hazard regression model was used to evaluate significance of serum ferritin levels as a prognostic factor. Results: A negative correlation between serum ferritin levels and survival time was found. After adjusting for sex, age, performance status, creatinine levels and white blood cell counts, serum ferritin levels were significantly associated with survival time. Conclusion: Even at the very end of life of terminal cancer patients, serum ferritin levels were an independent prognostic factor for survival.

• Economic and Environmental Geology
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• v.47 no.3
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• pp.227-235
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• 2014

For technology level assessment of KIGAM World Class Laboratories (WCL) candidates, bibliometric and qualitative analysis was conducted on their research papers listed on the SCIE database during 2009-2012. For the six research areas of geoscience and mineral resources, a research excellence indicator was applied using a Modified Rank Normalized Impact Factor (mrnIF), which was introduced by Heo et al. (2008) and Cho (2013). The KIGAM research department in rare metals utilization had the highest score for Impact Factor (IF) per paper in 2012 but the groundwater department or the exploration geophysics department came first based on the position and the mrnIF. Applying the mrnIF, the KIGAM research department in groundwater achieved excellent results in 2009 and 2011 and the urban mine department or exploration geophysics department came first place in other years. In the groundwater area, the percentage of research papers over 80 or 90 mrnIF, using Cho (2013)'s research excellence index, was the highest in 2011. The Cho (2013)'s excellent research indicator, 20%, the ratio of over 90 mrnIF was matched in the urban mining area for the whole research period, 2009-2012, and in the groundwater area for several years except 2010. Qualitative analysis of research papers can show the technology level of research departments. KIGAM World Class Laboratories (WCL) candidates should focus on increasing the quality and the quantity of their research papers.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.380-388
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• 2019

The studies regarding soil bacterial community and correlation analysis of wild-simulated ginseng cultivation area are insufficient. The purpose of this study was to investigate the correlation between soil bacterial community and growth characteristics of wild-simulated ginseng for selection of suitable cultivation area. The bacterial community was investigated by high throughput sequencing technique (Illumina platform). The correlation coefficient between soil bacterial community and growth characteristics were analyzed using Spearman's rank correlation. The soil bacterial community from soil samples of 8 different wild-simulated ginseng cultivated area exhibited two distinct clusters, cluster 1 and cluster 2. The relative abundance of Proteobacteria (35.4%) and Alphaproteobacteria(24.4%) was observed to be highest in all soil samples. The lower soil pH and higher abundance of Acidobacteria resulted in increased growth of wild-simulated ginseng. Additionally, abundance of Acidobacteriia (class) and Koribacteraceae (family) demonstrated significant positive correlation with fresh weight of wild-simulated ginseng. The results of this study clearly state the correlation between growth characteristic and soil bacterial community of wild-simulated ginseng cultivation area, thereby offering effective insight into selection of suitable cultivation area of wild-simulated ginseng.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.495-502
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• 2007

Species biotic index (SBI), based on a fish assemblage, was applied to a stream assessment using long-term ecological fish data set (1996 to 2001) in Boryong dam area, which is located in the mainstream of Ungchun Stream of Chungnam province, Korea. According to the methods of Hilsenhoff (1988), the scores of tolerance guild assigned 10 classes to each species by its habitat and feeding guild, but modified current 7 criteria to 5 scoring standards due to unclear borderline among species. Relative abundance in the species number of upper stream guilds was only 7% of the total, whereas the abundance in the species number of middle to downstream upper stream guilds was 64%. Mean SBI, based on dataset in Site 1 during 1995-2001 averaged 5.10, which was judged as a "good" condition by the rank criteria of SBI. Before the dam construction, mean SBI in the Site 1 was 4.61, indicating a "good" condition, but after the dam construction, mean SBI was 5.60, indicating a "fair" condition. Trajectory analysis in the Site 1 showed significantly (One-way ANOVA, $F_{6,21}=3.26$, p=0.02) different among years, reflecting the changes of fish composition and population density by the dam construction, whereas Site 2 showed no significant changes ($F_{6,21}=1.00$, P =0.45) difference among years. Mean SBI prior to the dam construction in the Site 3 was 4.52 but after the construction, the value was 6.30, indicating a distinct difference between the pre- and post-dam construction. Trajectory analysis at the Site 3 supported this fact: Values of SBI showed significantly ($F_{6,21}$=14.37, p<0.01) different. Mean SBI was 4.67 in the Site 4, indicating a "good" condition in the health and the health rank was same as the sampling sites 1, 2, and 4. Trajectory in the Site 4 showed no significant ($F_{6,21}=2.35$, p=0.07) difference among the years. Overall, our trajectory analysis indicated that three of four sampling sites (sites 1, 3, 4) showed significant decreases (n=7, p<0.05) and that the proportions of sensitive species declined evidently in the sites 1 and 2 and the tolerant species increased in the dam sites. Our outcomes may be used as a key data for diagnosis of the long-term ecological impact in the future in the watershed.

• Journal of Chest Surgery
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• v.42 no.5
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• pp.610-614
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• 2009

Background: Several trials have reported on whether adjuvant chemotherapy for resected stage IB non-small cell lung cancer is needed. The aim of our study was to investigate prognostic factors for recurrence to help identify patients who should receive adjuvant chemotherapy. Material and Method: We reviewed the cases of 48 stage IB non-small cell lung cancer patients between 1997 and 2006. Disease-free survival and overall survival rates were calculated by the Kaplan-Meier method. Univariate analysis was performed with the log rank test and multivariate analysis was done using Cox's proportional hazard model. Result: The median follow-up time was 48 months. The overall survival rate was 55.9%, and the disease-free survival rate was 48.6%. Of 8 variables, two factors, visceral pleural invasion and Iymphovascular invasion, were prognostic factors of disease-free survival (univariate analysis). Visceral pleural invasion was a significant prognostic factor in multivariate analysis, and overall survival in com-pared one or more variable such as visceral pleural invasion or, and lymphovascular invasion with the other variables. Conclusion: Visceral pleural invasion was identified as a poor prognostic factor and it may help select which patients will benefit from adjuvant chemotherapy in addition to more comprehensive follow-up.