• 한국식품위생안전성학회지
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• 제23권3호
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• pp.206-211
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• 2008

식품의약품안전청 제2007-22호로 고시된 PSL-TL 검지법의 적용 가능성을 확인하기 위하여 국내에서 방사선 조사가 허가되어 있는 복합조미식품과 향신료를 대상으로 실시한 결과, 향신료의 조사되지 않은 1개 시료가 PSL 분석결과 중간시료로 분류되어 추가적으로 TL 분석을 실시한 결과 방사선 조사되지 않은 것으로 판단되었고, 나머지 조사되지 않은 시료들은 PSL 분석결과 음성시료로 판정되어 방사선 조사되지 않은 것으로 판단되었다. 방사선이 조사된 시료들은 PSL 분석에서 양성시료로 분류되어 추가적으로 TL 분석을 실시하여 glow curve가 나타나는 온도범위와 glow curve의 형태를 확인하고 TL ratio를 구한 결과, 방사선이 조사된 시료는 $150{\sim}250^{\circ}C$ 사이에서 아주 강한 강도의 glow curve를 보여주었고, TL ratio가 0.29이상을 나타내어 방사선 조사된 것으로 판단하였다. 따라서 PSL-TL 검지법의 적용가능성이 확인되었다.

• 한국산업보건학회지
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• 제32권4호
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• pp.340-349
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• 2022

Objectives: The importance of MSDS is emphasized for communicating hazardous information due to the increase in the types and usage of chemical substances. The purpose of this study is to assess the reliability of MSDS by collecting and examining paint thinners commercially available in South Korea. Methods: Twenty-five paint thinners were purchased at paint stores and the provision of MSDS was checked. Quantitative and qualitative analysis was performed on the chemical constituents of the thinners using GC-MSD and GC-FID. Reliability was evaluated by the MSDS collection rate for the paint thinners and calculating the rate of matching between laboratory analysis results and the contents and composition of chemical constituents given in the MSDS. Results: Unlike a study conducted in 2006, MSDS were provided for all 25 thinners. As a result of qualitative analysis using GC-MSD, 104 chemical substances were detected. The substances with the highest detection rate were identified in the order of toluene, butyl acetate, acetone, xylene, and ethyl benzene. A component matching rate of 41% was found by comparing the differences between the number of substances detected in laboratory testing and the number of substances listed in the MSDS. Benzene, a carcinogen not listed in the MSDS, was detected in two thinners produced by a small company. The detected benzene contents were 0.039 and 0.040%. When benzene is used, it should be strictly handled according to the Industrial Safety and Health Act. However, since it is not listed on the MSDS, it is judged that benzene was not being managed as a carcinogen in the workplaces where it is used. Conclusions: Since the reliability of MSDS, which play an important role in hazard communication, was evaluated to be low, it is necessary to systematically and continuously secure this reliability. In particular, carcinogens should be managed more strictly.

• Tuberculosis and Respiratory Diseases
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• 제79권2호
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• pp.91-97
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• 2016

Background: Chronic obstructive pulmonary disease (COPD) is sometimes complicated with pneumonia, but little is known about the risk factors that promote the development of pneumonia in COPD. These risk factors were evaluated in the present study. Methods: The data of 324 patients with COPD from a prospective multi-center observational cohort with obstructive lung disease were evaluated retrospectively. To identify risk factors for the development of pneumonia in COPD, the clinical and radiological data at enrollment and the time to the first episode of pneumonia were analyzed by Cox proportional hazard analysis. Results: The median follow-up time was 1,099 days and 28 patients (8.6%) developed pneumonia. The Cox analysis showed that post-bronchodilator forced expiratory volume in one second ($FEV_1$, % of predicted) and the computed tomography (CT) emphysema extent (inspiratory V950) were independent risk factors for the development of pneumonia (post-bronchodilator $FEV_1$: hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.94-1.00; p=0.048 and inspiratory V950: HR, 1.04; 95% CI, 1.01-1.07; p=0.01). Conclusion: Emphysema severity measured by CT and post-bronchodilator $FEV_1$ are important risk factors for the development of pneumonia in COPD.

• 한국식품과학회지
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• 제36권6호
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• pp.1032-1040
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• 2004

생식은 건강 지향적 식생활 양상의 변화로 최근 소비가 급증하고 있으나, 업체의 영세성에 따른 위생관리가 미비하며 제조공정의 표준화가 되어 있지 않아 안전성 문제가 대두되고 있다. 본 연구는 생식의 위생적 생산을 위한 생식 생산 공정의 HACCP 일반모델을 개발을 위해 생식 원료의 세척에서부터 최종제품 포장까지 각 제조공정별로 생물학적, 물리적, 화학적 요인의 위해요인을 분석하고 중요관리점(CCPs)를 설정하고자 하였다. 원료의 세척부터 최종제품 포장까지 각 제조공정별로 생물학적, 물리적, 화학적 요인의 위해요인을 분석하였다. 생식원료의 오염수준은 $2.82-8.23\;{\log}_{10}\;CFU/g$의 일반세균수가 검출되었으며, 또한 $1.40-6.57\;{\log}_{10}\;CFU/g$의 coliforms이 검출되었다. 최종제품 중 일반세균수는 $1.51-7.40\;{\log}_{10}\;CFU/g$이 검출되었다. 제조공정 중 미생물 수 변화는 모든 원료에서 공정별로 유사한 패턴을 보여 주었는데 세척과 동결건조공정에서 일반세균수와 대장균군은 감소하였다. 물리적 요인인 이물 혼입과 화학적 요인인 수분함량의 변화가 위해 요인으로 분석되었다. 생식의 제조공정 중 CCP는 미생물 감소를 위한 세척 단계, 수분 관리를 위한 건조단계, 그리고 금속 등 이물질의 혼입단계로 설정되었다.

• 한국환경과학회지
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• 제22권11호
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• pp.1529-1538
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• 2013

Disasters like mountain landslides and collapse in cutting areas claim many a life and cause economic losses, involving much effort and expenses for their recovery. This study has surveyed and analyzed incident of disasters that had occurred on the sloping sides in Korea for the past 13 years in an effort to relieve damage caused by disasters on the sloping sides. The analysis confirms that while the major cause of disasters on the sloping side was storms in the past, frequency of disasters on sloping sides caused by local downpour is steadily on the rise. In addition, while disasters were concentrated in Gangwon Province, a mountainous region of the country, frequency of disasters occurring on the sloping sides is steadily increasing recently on the sloping sides in downtown areas in Seoul, Gyeonggi-do and so forth, attributing a large percentage of disasters to sloping sides. Data surveyed and analyzed in this study are thought to be applicable as basic data for the establishment of effective measures for the prevention of disasters occurring on the sloping sides in the days to come.

• Journal of Korean Neurosurgical Society
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• 제61권1호
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• pp.19-27
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• 2018

Objective : The objectives of this study were to evaluate the immediate and long-term efficacy and safety of coil embolization for large or giant aneurysms. Methods : One hundred and fifty large or giant aneurysm cases treated with endovascular coil embolization between January 2005 and February 2014 at a single institute were included in this study. Medical records and imaging findings were reviewed. Statistical analysis was performed to evaluate prognostic factors associated with major recurrence (major recanalization or rupture) and delayed thromboembolism after selective coil embolization. Results : Procedure-related symptomatic complications occurred in five (3.3%) patients. The mean clinical and radiological follow-up periods were 38 months (range, 2-110) and 26 months (range, 6-108), respectively. During the follow-up period, the estimated recurrence rate was 4.6% per year. Multivariate analysis using Cox regression showed the degree of occlusion to be the only factor associated with recurrence (p=0.008, hazard ratio 3.15, 95% confidence interval 1.34-7.41). The patient's history of rupture in addition to the size and location of the aneurysm were not associated with recurrence in this study. Delayed infarction occurred in eight cases, and all were incompletely occluded. Conclusion : Although immediate postprocedural safety profiles were reasonable, longterm results showed recanalization and thromboembolic events to occur continuously, especially in patients with incomplete occlusion. In addition, incomplete occlusion was associated with delayed thromboembolic complications. Patients with incomplete occlusions should be followed carefully for delayed recurrence or delayed thromboembolic events.

• Radiation Oncology Journal
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• 제32권4호
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• pp.247-255
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• 2014

Purpose: To determine whether neoadjuvant androgen deprivation therapy (NADT) improves clinical outcomes in patients with prostate cancer treated with definitive radiotherapy. Materials and Methods: We retrospectively reviewed medical records of 201 patients with prostate cancer treated with radiotherapy between January 1991 and December 2008. Of these, 156 patients with more than 3 years of follow-up were the subjects of this study. The median duration of follow-up was 91.2 months. NADT was given in 103 patients (66%) with median duration of 3.3 months (range, 1.0 to 7.7 months). Radiation dose was escalated gradually from 64 Gy to 81 Gy using intensity-modulated radiotherapy technique. Results: Biochemical relapse-free survival (BCRFS) and overall survival (OS) of all patients were 72.6% and 90.7% at 5 years, respectively. BCRFS and OS of NADT group were 79.5% and 89.8% at 5 years and those of radiotherapy alone group were 58.8% and 92.3% at 5 years, respectively. Risk group (p = 0.010) and radiation dose ${\geq}70Gy$ (p = 0.017) affected BCRFS independently. NADT was a significant prognostic factor in univariate analysis, but not in multivariate analysis (p = 0.073). Radiation dose ${\geq}70Gy$ was only an independent factor for OS (p = 0.007; hazard ratio, 0.261; 95% confidence interval, 0.071-0.963). Conclusion: NADT prior to definitive radiotherapy did not result in significant benefit in terms of BCRFS and OS. NADT should not be performed routinely in the era of dose-escalated radiotherapy.

• 한국치위생학회지
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• 제17권6호
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• pp.1095-1107
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• 2017

Objectives: This study was designed to provide raise awareness of the guidelines associated with radiation, including those associated with ensuring safety at dental clinics. Methods: A survey was conducted on the degree of awareness on dental radiation among adults over age 20 in Seoul and Gyeonggi Province from December 2016. The questionnaire copies from 21 respondents whose answers were insincere were excluded from analysis. A total of 320 copies, equivalent to 93.4% of the total data collected, were used in the analysis. Results: Dental radiography was found to have been experienced by 60. 5% of the subjects, and 83.4% of them did not receive any explanation to the radiation exposure, while 78.7% had no experience wearing protective equipment. As a result of investigating factors affecting the recognition of dental radiation, it was found that female subjects had a higher awareness of the hazards associated with dental radiation hazard and the necessity to provide information. Conclusions: It is necessary to educate the dental medical personnel to raise awareness on radiation exposure and the need for protective equipment, especially when checking for pregnancy.

• Journal of Chest Surgery
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• 제52권1호
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• pp.16-24
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• 2019

Background: Optimal graft selection for coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) dysfunction remains debatable. We report an analysis of our experiences of isolated CABG in patients with severe LV dysfunction and the impact of graft strategy on long-term outcomes. Methods: We analyzed 209 patients with severe LV dysfunction (ejection fraction [EF] <30%) who underwent primary isolated CABG. Of these, 169 were revascularized with a bilateral internal thoracic arterial (ITA) graft (BITA group) and 40 were revascularized with a single ITA graft (SITA group). The mean follow-up duration was $22{\pm}32$ months. Results: There were 18 early deaths (8.6%). Overall survival at 5 years was 66.7%. The rate of freedom from cardiac-related death at 5 years was 74.1%, and was significantly higher in patients who underwent off-pump CABG (p=0.005) and in the BITA group (p=0.023). Multivariate analysis demonstrated that old age (hazard ratio [HR], 2.548; 95% confidence interval [CI], 1.134-5.762; p=0.024), off-pump CABG (HR, 0.245; 95% CI, 0.090-0.661; p=0.006), and BITA grafts (HR, 0.333; 95% CI, 0.146-0.757; p=0.009) were correlated with cardiac mortality. Conclusion: CABG in patients with severe LV dysfunction (EF <30%) showed reasonable long-term outcomes. The rate of freedom from cardiac-related death was significantly higher in patients who underwent off-pump CABG and in the BITA group. Off-pump BITA grafting strategies can be accepted as a viable primary option in patients with severe LV dysfunction if performed by an experienced surgeon.

• 한국공간구조학회논문집
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• 제23권2호
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• pp.19-28
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• 2023

Timber structures are susceptible to moisture, contamination, and pest infestation, which can compromise their integrity and pose a significant fire hazard. Despite these drawbacks, timber's lightweight properties, eco-friendliness, and alignment with current architectural trends emphasizing sustainability make it an attractive option for construction. Moreover, timber structures offer economic benefits and provide a natural aesthetic that regulates building temperature and humidity. In recent years, timber domes have gained popularity due to their high recyclability, lightness, and improved fire resistance. Researchers are exploring hybrid timber and steel domes to enhance stability and rigidity. However, shallow dome structures still face challenges related to structural instability. This study investigates stability problems associated with timber domes, the behavior of timber and steel hybrid domes, and the impact of timber member positioning on dome stability and critical load levels. The paper analyzes unstable buckling in single-layer lattice domes using an incremental analysis method. The critical buckling load of the domes is examined based on the arrangement of timber members in the inclined and horizontal directions. The analysis shows that nodal snapping is observed in the case of a concentrated load, whereas snap-back is also observed in the case of a uniform load. Furthermore, the use of inclined timber and horizontal steel members in the lattice dome design provides adequate stability.