• Korean Journal of Radiology
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• 제24권3호
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• pp.235-246
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• 2023

Objective: It is difficult to predict the treatment response of tissue after stereotactic radiosurgery (SRS) because radiation necrosis (RN) and tumor recurrence can coexist. Our study aimed to predict tumor recurrence, including the recurrence site, after SRS of brain metastasis by performing a longitudinal tumor habitat analysis. Materials and Methods: Two consecutive multiparametric MRI examinations were performed for 83 adults (mean age, 59.0 years; range, 27-82 years; 44 male and 39 female) with 103 SRS-treated brain metastases. Tumor habitats based on contrast-enhanced T1- and T2-weighted images (structural habitats) and those based on the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) images (physiological habitats) were defined using k-means voxel-wise clustering. The reference standard was based on the pathology or Response Assessment in Neuro-Oncologycriteria for brain metastases (RANO-BM). The association between parameters of single-time or longitudinal tumor habitat and the time to recurrence and the site of recurrence were evaluated using the Cox proportional hazards regression analysis and Dice similarity coefficient, respectively. Results: The mean interval between the two MRI examinations was 99 days. The longitudinal analysis showed that an increase in the hypovascular cellular habitat (low ADC and low CBV) was associated with the risk of recurrence (hazard ratio [HR], 2.68; 95% confidence interval [CI], 1.46-4.91; P = 0.001). During the single-time analysis, a solid low-enhancing habitat (low T2 and low contrast-enhanced T1 signal) was associated with the risk of recurrence (HR, 1.54; 95% CI, 1.01-2.35; P = 0.045). A hypovascular cellular habitat was indicative of the future recurrence site (Dice similarity coefficient = 0.423). Conclusion: After SRS of brain metastases, an increased hypovascular cellular habitat observed using a longitudinal MRI analysis was associated with the risk of recurrence (i.e., treatment resistance) and was indicative of recurrence site. A tumor habitat analysis may help guide future treatments for patients with brain metastases.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3335-3340
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• 2016

Background: Oral submucous fibrosis (OSF) is a precancerous condition with a 4 to13% malignant transformation rate. Related to the habit of areca nut chewing it is mainly prevalent in South-east Asian countries where the habit of betel quid chewing is frequently practised. On chewing, alkaloids and polyphenols are released which undergo nitrosation and give rise to N-nitrosamines which are cytotoxic agents. CYP450 is a microsomal enzyme group which metabolizes various endogenous and exogenous chemicals including those released by areca nut chewing. CYP1A1 plays a central role in metabolic activation of these xenobiotics, whereas CYP2E1 metabolizes nitrosamines and tannins. Polymorphisms in genes that code for these enzymes may alter their expression or function and may therefore affect an individuals susceptibility regarding OSF and oral cancer. The present study was therefore undertaken to investigate the association of polymorphisms in CYP1A1 m2 and CYP2E1 (RsaI/PstI) sites with risk of OSF among areca nut chewers in the Northern India population. A total of 95 histopathologically confirmed cases of OSF with history of areca nut chewing not less than 1 year and 80, age and sex matched controls without any clinical signs and symptoms of OSF with areca nut chewing habit not less than 1 year were enrolled. DNA was extracted from peripheral blood samples and polymorphisms were analyzed by PCR-RFLP method. Gene polymorphism of CYP1A1 at NcoI site was observed to be significantly higher (p = 0.016) in cases of OSF when compared to controls. Association of CYP1A1 gene polymorphism at NcoI site and the risk of OSF (Odd's Ratio = 2.275) was also observed to be significant. However, no such association was observed for the CYP2E1 gene polymorphism (Odd's Ratio = 0.815). Our results suggest that the CYP1A1 gene polymorphism at the NcoI site confers an increased risk for OSF.

• 한국터널지하공간학회 논문집
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• 제22권2호
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• pp.155-170
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• 2020

본 논문의 목적은 NATM 터널에 적용 가능한 리스크 관리 시스템을 구축하는 것이다. 이를 위해 먼저 NATM 터널 현장의 붕괴 사례를 조사하고, 이를 바탕으로 NATM 터널시공 중 발생 가능한 리스크 사건과 그 발생원인인 리스크 요인을 분석하였다. 리스크 요인은 지질, 설계, 시공 리스크 요인의 세 가지 카테고리로 구분하여 분석하였고, 리스크 사건은 과대변형, 과대변형 및 지표침하, 터널내부 붕락, 붕락 및 지표침하/함몰의 네 가지 유형으로 분석하였다. 또한, 리스크 요인으로부터 리스크 사건이 발생하는 일련의 리스크 시나리오를 리스크 요인별로 식별하였으며, 해당 NATM 터널 리스크 시나리오에 대한 리스크 분석 및 평가 방안을 제시하였다. 평가결과에 따라 리스크 대응이 필요한 시나리오에 대해 최적의 리스크 저감 대책공법을 선정하는 방안을 제시하였고, 일련의 NATM 터널 리스크 관리 프로세스를 효과적으로 수행할 수 있도록 NATM 터널 리스크 등록부 및 대책공법 관리대장을 개발하였다. 또한, 구축한 리스크 관리 시스템을 실제 도로터널 프로젝트에 적용하여 리스크 식별, 분석 및 평가, 대응 과정을 수행함으로써 그 타당성을 검증하였다.

• 한국건축시공학회지
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• 제18권6호
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• pp.611-619
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• 2018

현재까지의 건설 안전관리와 리스크에 관한 연구들은 건설현장 내부(근로자)에 한정되어 있어 건설현장 외부(제 3자)에 대한 연구는 미비한 실정이다. 그 결과, 건설현장 주변의 일반인들이 피해를 받고 있으며 산재 다발이라는 부정적인 이미지로 언론이나 일반 대중들에게 투영되고 있다. 일반 대중들에게 부정적인 이미지를 탈피하기 위해서는 건설현장 내부(공종, 건축물)에만 집중되어있는 기존의 안전관리가 아닌 건설 현장 외부(제 3자)에 대해서도 고려된 종합적 안전관리체계를 구축해야 한다. 이에 본 연구에서는 건설 현장 외부(제 3자)의 인명사고 리스크를 정량화하고 몬테카를로 시뮬레이션을 활용하여 리스크가 어떻게 변화할 것인지 예측하고자 한다. 이를 위하여 첫째, 선행연구를 고찰하여 불안전한 상태와 인명사고 발생형태를 정의한다. 둘째, 14년 간 건설현장 외부에서 발생한 제 3자 인명 손해배상액 데이터를 수집한다. 셋째, 수집된 데이터의 사고내용을 분석하여 사고 발생분석 모델을 설정한다. 넷째, 리스크 정량화 모델을 구축하고 불안전한 상태, 인명사고 발생형태별 사고발생확률과 손해배상액 확률분포를 제시한다. 마지막으로 몬테카를로 시뮬레이션을 통해 도출된 사고 형태별 분포결과를 분석한다. 본 연구의 결과는 향후 건설현장 내 외부 안전관리 체크리스트 개발 및 인명사고 예측 관리 시스템 개발의 참고 자료로 활용될 것으로 기대된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5957-5960
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• 2013

Background: Gliomas are the most common type of primary brain tumor in adults, and the X-ray repair complementing group 1 gene (XRCC1) is an important candidate gene influencing its risk. The objective of this study was to detect the influence of XRCC1 genetic polymorphisms on glioma risk. Materials and Methods: A total of 629 glioma patients and 641 cancer-free subjects were enrolled in this case-control study. The genotypes of the c.1471G>A genetic polymorphism were determined by created restriction site-polymerase chain reaction (CRS-PCR) and DNA sequencing methods. The influence of the XRCC1 genetic polymorphism on glioma risk was evaluated by association analysis. Results: Our data indicated that the alleles/genotype of this genetic variant was statistically associated with glioma risk. The AA genotype was statistically associated with the increased risk of glioma compared to the GG wild genotype (odds ratios (OR) = 1.89, 95% CI 1.25-2.87, P = 0.003). The allele-A may contribute to increased the susceptibility to glioma (OR = 1.23, 95% CI 1.04-1.46, P = 0.017). Conclusions: These preliminary findings indicate that the c.1471G>A genetic polymorphism of XRCC1 has the potential to influence glioma susceptibility, and might be used as molecular marker for assessing glioma risk.

• 한국안전학회지
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• 제30권3호
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• pp.73-79
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• 2015

In consideration of current circumstances which management activities for safety performance on construction sites are mostly controlled by safety personnel, it is necessary to maintain qualified safety personnel those who are experienced and have adequate ability. This is a major factor in order to prevent any of work related incident in the construction site. However, the existing standard which enforces certain number of safety personnel in the construction site aligning with respective contract amount could lead to difficulties for proactive safety management. So, it is required to get improvement on the existing standard. In nominating the proper number of safety personnel, it would be more efficient to consider the level of risk for characteristic of work itself and the total number of manpower mobilized in respective construction work, rather than to follow the existing standard of manpower ratio as per the contract amount. Hence, this study aims to propose several plans which enable to improve the existing standard for assignment of safety personnel on construction sites.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.474-480
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• 2001

Purpose: The aim of this study was to evaluate the complications of open reduction and internal fixation of mandibular fracture with miniplates. Patients and Methods: A total of 134 patients who presented with 196 fractures were analyzed retrospectively. Complications were evaluated for factors such as age, the site of fracture, the severity of fracture, delayed operation, preoperative wound contamination, the site and disposition of teeth in the fracture line and midfacial fractures. Statistical analysis was used to compare complications to risk factors. Results: Of the 134 patients, 20 patients had some form of postoperative complications and complication rate was 14.9%. These complications included infection, plate fracture, malocclusion, wound dehiscence, nerve injury and nonunion. There was a significant correlation between complication rate and the severity of fracture, preoperative wound contamination and the site of the fracture and disposition of teeth(p<0.05). Conclusion: The occurrence of postoperative complications in the treatment of mandibular fractures was related to the severity of fracture, preoperative wound contamination and the site of the fracture and disposition of teeth.

• 대한안전경영과학회지
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• 제17권4호
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• pp.23-33
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• 2015

Recently, the Ministry of Employment and Labor Management is a trend to strengthen all men death rate than the accident rate. Points reduction in the accident rate change orders related to credit rating score to +2 points in his plans as part of +1 point. In addition, according to the fancy linger RISK treatment in the event of a disaster site and fiction treatment to achieve accident-free during processing the scene interspersed with equity issues have been raised. In general disaster for the problem in the first two cases occurs when abnormal process according to the disaster site manager positions dismissal policy, each division headquarters itself, interspersed disasters performance compared to processing in accordance with the refrain, processing expenses in accordance with the composition of untreated industrial accident, costs and burdens partners FTC, there is a possibility that the issues raised, such as the Ministry of Employment and Labor. In response to domestic social practices focused on the construction site practices and prevention measures should be evaluated with respect to what.

• Journal of Ecology and Environment
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• 제43권3호
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• pp.289-296
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• 2019

We investigated the mortality and the oxidative damages of Deschampsia antarctica in response to waterlogging stress. In field, we compared the changes in the density of D. antarctica tuft at the two different sites over 3 years. The soil water content at site 2 was 6-fold higher than that of site 1, and the density of D. antarctica tuft decreased significantly by 55.4% at site 2 for 3 years, but there was no significant change at site 1. Experimental results in growth chamber showed that the $H_2O_2$ and malondialdehyde content increased under root-flooding treatment (hypoxic conditions-deficiency of $O_2$), but any significant change was not perceptible under the shoot-flooding treatment (anoxic condition-absence of $O_2$). However, total chlorophyll, soluble sugar, protein content, and phenolic compound decreased under the shoot-flooding treatment. In addition, the catalase activity increased significantly on the 1st day of flooding. These results indicate that hypoxic conditions may lead to the overproduction of reactive oxygen species, and anoxic conditions can deplete primary metabolites such as sugars and protein in the leaf tissues of D. antarctica. Under present warming trend in Antarctic Peninsula, D. antarctica tuft growing near the shoreline might more frequently experience flooding due to glacier melting and inundation of seawater, which can enhance the risk of this plant mortality.

• 한국안전학회지
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• 제33권6호
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• pp.115-122
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• 2018

This study examined the effect of safety leadership coaching program on managers' safety management and workers' safety behaviors in construction site. Three or four managers and about one hundred workers at each site participated in this study. Safety leadership coaching program consisted of safety leadership education, goal setting, self-monitoring and feedback on workers' safety behavior, reward for three safety management behaviors; (1) safety observations of workers safety behavior and (2) providing positive feedback on safe behavior (3) providing corrective feedback on risk behavior and daily safety education for workers. Dependent variables were the percentage of safe behaviors of workers and frequency of managers' safety management behaviors. A nonconcurrent AB multiple baseline design across settings was adopted. After baseline(A), safety leadership coaching program (B) was introduced to each site. The results showed that safety leadership coaching program was effective to increase managers' and workers' safety behaviors. These results suggest that safety leadership coaching program developed in this study would be an alternative treatment technique to improve construction safety management. In addition, the implications, limitations of this study, and future studies are discussed.