• Journal of Radiation Protection and Research
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• 제44권3호
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• pp.97-102
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• 2019

Background: Dose rate meters are the most widely used, and perhaps one of the most important tools for the measurement of ionising radiation. They are often the first, or only, device available to a user for an instant check of radiation dose at a certain location. Throughout the world, radiation safety practices rely strongly on the output of these dose rate meters. But how well do we know the quality of their output? Materials and Methods: This review is based on the measurements 1,158 commercially available dose rate meters of 116 different makes and models. Expected versus the displayed dose patterns and consistency was checked at various dose rates between $5{\mu}Gy{\cdot}h^{-1}$ and $2mGy{\cdot}h^{-1}$. Samples of these meters were then selected for further investigation and were exposed to radiation sources covering photon energies from 50 keV to 1.5 MeV. The effect of detector orientation on its reading was also investigated. Rather than focusing on the angular response distribution that is often reported by the manufacturer of the device, this study focussed on the design ergonomics i.e. the angles that the operator will realistically use to measure a dose rate. Results and Discussion: This review shows the scope and boundaries of the ionising radiation dose rate estimations that are made using commonly available meters. Observations showed both inter and intra make and model variations, occasional cases of instrument failure, instrument walk away, and erroneous response. Conclusion: The results indicate the significance of selecting and maintaining suitable monitors for specific applications in radiation safety.

• 치위생과학회지
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• 제19권3호
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• pp.162-169
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• 2019

Background: Oral diseases are caused by various systemic and local factors, the most closely related being the biofilm. However, the challenges involved in removing an established biofilm necessitate professional care for its removal. This study aimed to evaluate and compare the effects of professional self and professional biofilm care in healthy patients to prevent the development of periodontal diseases. Methods: Thirty-seven patients who visited the dental clinic between September 2018 and February 2019 were included in this study. Self-biofilm care was performed by routine tooth brushing and professional biofilm care was provided using the toothpick method (TPM) or the oral prophylaxis (OP) method using a rubber cup. Subgingival bacterial motility and halitosis (levels of hydrogen sulfide, $H_2S$; methyl mercaptan, $CH_3SH$; and di-methyl sulfide, $(CH_3)_2S$) were measured before, immediately after, and 5 hours after the preventive treatment in the three groups. Repeated measures analysis of variance test was performed to determine significant differences among the groups. Results: TPM was effective immediately after the prevention treatment, whereas OP was more effective after 5 hours (proximal surfaces, F=16.353, p<0.001; smooth surfaces, F=66.575, p<0.001). The three components responsible for halitosis were effectively reduced by professional biofilm care immediately after the preventive treatment; however, self-biofilm care was more effective after 5 hours ($H_2S$, F=3.564, p=0.011; $CH_3SH$, F=6.657, p<0.001; $(CH_3)_2S$, F=21.135, p<0.001). Conclusion: To prevent oral diseases, it is critical to monitor the biofilm. The dental hygienist should check the oral hygiene status and the ability of the patient to administer oral care. Professional biofilm care should be provided by assessing and treating each surface of the tooth. We hope to strengthen our professional in biofilm care through continuous clinical research.

• 한국정보시스템학회지:정보시스템연구
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• 제28권2호
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• pp.53-72
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• 2019

Purpose The purpose of this study is to examine the impact of tie strength in the network of industrial clustering on the knowledge acquisition, integration and innovation performance of small and medium sized enterprises. We test the positive relationship of weak tie and knowledge acquisition, strong tie and knowledge integration, and the interaction effect of two tie strengths on both processes of knowledge acquisition and integration. By identifying these relationships, we can better understand how to manage the attributes of social networks in terms of tie strength in order to improve the performance of innovation for the small and medium sized enterprises. Design/methodology/approach We collect 200 survey data from 2 industrial cluster respectively: Pankyo and Guroo. In Pankyo, the proportion of IT industry is the highest (35%) while the proportion of manufacturing is highest (35%) in Guroo. Pooling the data from two industrial cluster, we check the reliability and validity of our research model and test the hypotheses. Findings First, we find the positive relationship of weak tie and knowledge acquisition from both industrial clustering. Weak tie is composed of heterogeneous organizations with various background and expertise. The communication and information sharing of organizations in the weak tie network helps the idea generation for organization's innovation, which is the knowledge acquisition process. Second, the relationship of strong tie and knowledge integration is insignificant. Typically the strong tie from long-lasting partnership is expected to be beneficial in the action stage of innovation, which is the knowledge integration process. However it is not identified in our industry cluster. Finally, the interaction effect of weak and strong tie is identified to be effective on both knowledge acquisition and integration processes.

• Nutrition Research and Practice
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• 제13권6호
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• pp.543-554
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• 2019

BACKGROUND/OBJECTIVES: The elderly are reported to have a high prevalence of nutritional anemia when they have lower intakes of nutrients or chronic diseases. This study was conducted to compare nutritional status according to nutritional anemia and to determine associations between nutritional anemia and chronic diseases in Korean elderly. SUBJECTS/METHODS: This study utilized data on 3,258 elderly aged ${\geq}65$ years gathered during the $6^{th}$ Korea National Health and Nutrition Examination Survey 2013-2015. Subjects were divided into nutritional anemia (NA) group (n = 415) and non-NA group (n = 2,843) by hemoglobin concentration. Nutrient intakes were assessed using dietary intake data obtained using the 24-hour recall method. The odds ratios (ORs) for nutritional anemia by chronic diseases were determined. Statistical analysis was performed using SPSS Ver. 23.0. RESULTS: Of 3,258 subjects, 12.7% had nutritional anemia. Intakes of potatoes, pulses, and mushrooms by males and potatoes, fruits, meats, eggs, and seafood by females were significantly lower in NA group than in non-NA group. The proportion of the subjects whose intakes of protein, vitamin A, vitamin $B_1$, vitamin $B_2$, niacin, and iron less than estimated average requirement (EAR) were significantly higher in NA group compared to non-NA group. After adjusting for age, the number of family members, energy intake, and alcohol drinking, ORs for nutritional anemia in the subjects with diabetes and myocardial infarction or angina pectoris were significantly higher by 1.74 times and 1.59 times as compared to the subjects without those diseases, respectively. However, ORs for nutritional anemia in the subjects with obesity, abdominal obesity, and hypertriglyceridemia were significantly lower by 0.64 times, 0.60 times, and 0.59 times as compared to the subjects without those diseases, respectively. CONCLUSIONS: The results of this study suggested that nutritional management should be done to enable the Korean elderly to consume foods with high hematopoietic nutrients density to prevent nutritional anemia. Korean elderly need to make regular efforts to check for nutritional anemia.

• Nutrition Research and Practice
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• 제15권1호
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• pp.38-53
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• 2021

BACKGROUND/OBJECTIVES: Abdominal obesity is associated with metabolic disorders, and, in recent years, its prevalence in Korea has continuously increased. The change of lifestyle, particularly diet, is critical for the reduction of abdominal obesity. This study evaluated the effectiveness of an intervention focused on dietary self-efficacy and behaviors on the improvement of abdominal obesity. SUBJECTS/METHODS: Abdominally obese adults with additional cardiovascular risk factors were recruited through 16 medical facilities in South Korea from the year 2013 to 2014. The participants were randomly divided into 2 groups: an intensive intervention group (IG) that received a multi-component intervention to reduce abdominal obesity, by mainly focusing on dietary attitude and dietary behavior change, and a minimal information intervention group (MG) that received a brief explanation of health status and a simple recommendation for a lifestyle change. The interventions were provided for 6 mon, and health examinations were conducted at baseline, 3-, 6-, and 12-mon follow-ups. A path analysis was conducted to identify the process governing the changes in abdominal obesity. RESULTS: The IG showed an improvement in self-efficacy for eating control and diet quality at 6-mon follow-up. Abdominal obesity improved in both groups. Waist circumference was observed to be decreased through the path of "improved self-efficacy for eating control in food availability-eating restriction-improved dietary quality" in IG. Most changes in follow-ups were not significantly different between two groups. CONCLUSIONS: The intensive program targeting the modification of dietary behavior influenced management of abdominal obesity, and the effect occurred through a step-by-step process of change in attitude and behavior. Generally, improvements were also seen in the MG, which supports the necessity of regular health check-ups and brief consultation. The results can be used for further development and implementation of more successful interventions.

• 한국임상약학회지
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• 제30권4호
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• pp.234-242
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• 2020

Background: Bevacizumab-induced proteinuria is known to occur when vascular endothelial cell receptors are blocked, which leads to decreased protein filtration. Although several studies have analyzed the correlation between therapeutic effect of bevacizumab and proteinuria, no conclusion has been established. Methods: In this retrospective study, colorectal cancer patients who received bevacizumab and urinary protein check from January 2015 to December 2016, were included. The incidence of proteinuria and the grade according to Common Terminology Criteria for Adverse Events (CTCAE) 4.0 were evaluated after bevacizumab administration. The primary objective was to correlate proteinuria with overall response rate (ORR) and time to progression (TTP). Primary lesion, metastasized organs, surgery or radiation therapy, chemotherapy were investigated for analysis of risk factors for proteinuria development. Results: A total of 149 patients included in the analysis. Proteinuria occurred 19.5% (n=29) in the study patients; 20 in grade 1, 7 in grade 2, and 2 in grade 3. ORR was 55.2% in the proteinuria group and 51.7% in the non-proteinuria group. There was no difference between two groups (p=0.89). The TTP through the survival curve was similar in both groups (10 months, p=0.97). The risk of proteinuria was high in patients who had liver metastasis (p=0.02) and no surgery (p=0.01). Conclusions: These result indicates that bevacizumab-induced proteinuria expression was not correlated with the therapeutic effect on patients with colorectal cancer. Further analysis is required to find out the correlation between proteinuria and therapeutic effects. The risk of proteinuria was increased from patients who had liver metastasis, and no surgery.

• Infection and chemotherapy
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• 제50권4호
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• pp.319-327
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• 2018

Background: Lancet-related needlestick injuries (NSIs) occur steadily in clinical practices. Safety-engineered devices (SEDs) can systematically reduce NSIs. However, the use of SEDs is not active and no study to guide the implementation of SEDs was known in South Korea. The lancet-related NSIs may be eliminated to zero incidence using a SED lancet with effective sharp injury protection and reuse prevention features. Materials and Methods: We implemented a SED lancet by replacing a conventional prick lancet in a tertiary hospital in a sequential approach. A spot test of the new SED was conducted for 1 month to check the acceptability in practice and a questionnaire survey was obtained from the healthcare workers (HCWs). A pilot implementation of the SED lancet in 2 wards was made for 1 year. Based on these preliminary interventions, a hospital-wide full implementation of the SED lancet was launched. The incidence of NSIs and cost expenditure before and after the intervention were compared. Results: There were 29 cases of conventional prick lancet-related NSIs for 3 years before the full implementation of SED lancet. The proportion of prick lancet-related NSIs among yearly all kinds of NSIs during two years before the pilot study was average 11.7% (22/188). Pre-interventional baseline incidence of all kinds of NSIs was 7.01 per 100 HCW-years. After the full implementation of SED lancet, the lancet-related NSIs became zero in the 2nd year (P = 0.001). The average direct cost of 18,393 US dollars (USD) per year from device and post-exposure medical care before the intervention rose to 20,701 USD in the 2nd year of the intervention. The incremental cost-effectiveness ratio was 210 USD per injury avoided. Conclusion: The implementation of a SED lancet could eliminate the lancet-related NSIs to zero incidence. The cost increase incurred by the use of SED lancet was tolerable.

• International journal of thyroidology
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• 제10권2호
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• pp.96-101
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• 2017

Background and Objectives: Anaplastic thyroid carcinoma (ATC) is commonly related with concurrent differentiated thyroid carcinoma (DTC). We aimed to examine the clinicopathologic characteristics, prognosis and gene expression of DTC with anaplastic foci. Materials and Methods: Eighteen patients with DTC with anaplastic foci were enrolled in this study. To compare the clinicopathologic characteristics and prognosis of anaplastic foci subjects with conventional ATC or DTC, we additionally included 12 ATC and 1030 DTC patients who diagnosed during same period. Immunohistochemistry was performed to check the gene expression in anaplastic foci and DTC component. Results: In anaplastic foci group, tumor size was larger ($2.5{\pm}1.3$ vs. $1.2{\pm}0.9cm$, p=0.001), distant metastasis was more frequent (11.1 vs. 0%, p=0.000) and 1-year survival rate was low (88.9 vs. 100%, p=0.000) than DTC group. In contrast, compared with ATC group, anaplastic foci group showed younger age at diagnosis ($50{\pm}16$ vs. $63{\pm}18years$, p=0.039), smaller tumor size ($2.5{\pm}1.3$ vs. $3.8{\pm}1.4cm$, p=0.027), less distant metastasis (11.1 vs. 41.7%, p=0.084) and longer 1-year survival rate (88.9 vs. 25.0%, p=0.001). Expression of p53 protein was observed in 100% of anaplastic foci, ATC and 12.5% of papillary thyroid carcinoma component. Conclusion: DTC with foci of anaplastic transformation has a worse prognosis than DTC, but a better prognosis than ATC. Our results support that DTC with anaplastic foci was intermediate state from DTC to ATC.

• 대한두경부종양학회지
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• 제37권2호
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• pp.19-24
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• 2021

Background/Objectives: The aim of this national population-based retrospective study was to analyze the status and treatment outcome in patients with hypopharyngeal cancer. Materials & Methods: Participants were included in the KNHIS national sample cohort who received a KNHIS health check-up in 2008 and 2009, and we followed these individuals until 2017. Patients were defined as having hypopharynx cancer if they had admissions records for hypopharynx cancer in their national health insurance data from 2010 to 2017. Results: The study cohort included 3,922 patients. According to our nationwide data, 3,533(90.1%) were male with a median age of 65.03±11.04 years at the time of diagnosis. Among parametric models for hypopharyngeal cancer prognosis, old age (Hazard ratio [HR]:1.92; 95% confidence interval[CI]:1.76-2.09), female (HR:0.77; 95% CI:0.66-0.89), and low socioeconomic status (HR:1.216; 95% CI:1.114-1.327) were significantly associated with survival. Compared with concurrent chemoradiotherapy, patients who received no treatment (HR, 1.88; 95% CI, 1.31-2.70), neoadjuvant chemotherapy followed by surgery (HR, 1.21; 95% CI, 1.04-1.41), and chemotherapy alone (HR, 1.16; 95% CI, 1.03-1.27) showed poor prognosis in hypopharyngeal cancer. Conclusion: Our data indicated that age, sex, and income were significant predictors of lifetime survival in patients with hypopharyngeal cancer. Treatment modalities were also associated with prognosis. The data have implications for treatment investigations and prevention strategies.

• Safety and Health at Work
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• 제13권2호
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• pp.240-247
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• 2022

Background: Although insomnia and constipation are highly prevalent worldwide, studies examining a possible association between them are lacking. We examined the relationship between insomnia and constipation in shift workers who have a high prevalence of insomnia and other diseases. Methods: This study had a multicenter cross-sectional design and conducted using health examination data including self-reported questionnaires. In total, 12,879 and 4,650 shift workers were enrolled in Severance Hospital and Wonju Severance Hospital, respectively, during 2015-2017. Multivariate logistic regression models and subgroup analysis were performed in each center with the same protocol, using a common data model. Results: The mean age of the total population was 44.35 (standard deviation = 8.75); the proportion of males was 56.9%. Female sex, being underweight and non-smoker were strongly associated with an increased risk of constipation symptom (p < 0.001). Pooled odds ratios (ORs) were calculated using ORs of both centers with weights; there was a significant dose-response relationship (sub-threshold 1.76 [95% confidence interval [CI] 1.62-1.91]; moderate 2.28 [95% CI 2.01-2.60]; severe 4.15 [95% CI 3.18-5.41] in the final model, p for trend < 0.001). Subgroup analysis performed by stratifying sex and pooled ORs showed a similar trend to that of the entire group. Conclusion: We observed a strong correlation between insomnia and constipation in this population. Our findings may help in formulating guidelines and policies to improve quality of life in shift workers through the management of sleep quality and proper bowel function. This study is the first to report this relationship among people working in shifts.