• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8861-8869
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• 2014

Background: The prognostic value of Bcl-2 protein expression in non-small cell lung cancer (NSCLC) is under debate. We therefore systematically reviewed the evidence for Bcl-2 protein effects on NSCLC survival to elucidate this issue. Materials and Methods: An electronic search in Pubmed and Embase complemented by manual searches in article references were conducted to identify eligible studies to evaluate the association between Bcl-2 protein expression and overall survival (OS) as well as disease free survival (DFS) of NSCLC patients. Combined hazard ratios (HRs) with corresponding 95% confidence intervals (95%CIs) were pooled using the random-effects model. Results: A total of 50 trials (including 52 cohorts) encompassing 7,765 patients were pooled in the meta-analysis regarding Bcl-2 expression and OS of NSCLC patients. High expression of Bcl-2 protein had a favorable impact (HR=0.76, 95%CI=0.67-0.86). In the group of Bcl-2 expression and DFS, 11 studies including 2,634 patients were included. The synthesized result indicated high expression of Bcl-2 protein might predict good DFS (HR=0.85, 95%CI=0.75-0.95). Conclusions: Our present meta-analysis demonstrated favorable prognostic values of Bcl-2 expression in patients with NSCLC. Further prospective trails are welcomed to validate the utility of assessing Bcl-2 in NSCLC patient management.

• Computers and Concrete
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• 제21권6호
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• pp.717-726
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• 2018

Concrete pipelines are the most efficient and safe means for gas and oil transportation over a long distance. The use of nano materials and nono-engineering can be considered for enhancing concrete pipelines properties. the tests show that $SiO_2$ nanoparticles can improve the mechanical behavior of concrete. Moreover, severe hazard for pipelines is seismic ground motion. Over the years, scientists have attempted to understand pipe behavior against earthquake most frequently via numerical modeling and simulation. Therefore, in this paper, the dynamic response of underwater nanocomposite submerged pipeline conveying fluid is studied. The structure is subjected to the dynamic loads caused by earthquake and the governing equations of the system are derived using mathematical model via Classic shell theory and Hamilton's principle. Navier-Stokes equation is employed to calculate the force due to the fluid in the pipe. As well, the effect of external fluid is modeled with an external force. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite. 1978 Tabas earthquake in Iran is considered for modelling seismic load. The dynamic displacement of the structure is extracted using differential quadrature method (DQM) and Newmark method. The effects of different parameters such as $SiO_2$ nanoparticles volume percent, boundary conditions, thickness to radius ratios, length to radius ratios, internal and external fluid pressure and earthquake intensity are discussed on the seismic response of the structure. From results obtained in this paper, it can be found that the dynamic response of the pipe is increased in the presence of internal and external fluid. Furthermore, the use of $SiO_2$ nanoparticles in concrete pipeline reduces the displacement of the structure during an earthquake.

• Computers and Concrete
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• 제24권2호
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• pp.125-135
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• 2019

Concrete pipelines are the most efficient and safe means for gas and oil transportation over a long distance. The use of nano materials and nono-engineering can be considered for enhancing concrete pipelines properties. the tests show that SiO2 nanoparticles can improve the mechanical behavior of concrete. Moreover, severe hazard for pipelines is seismic ground motion. Over the years, scientists have attempted to understand pipe behavior against earthquake most frequently via numerical modeling and simulation. Therefore, in this paper, the dynamic response of underwater nanocomposite submerged pipeline conveying fluid is studied. The structure is subjected to the dynamic loads caused by earthquake and the governing equations of the system are derived using mathematical model via Classic shell theory and Hamilton's principle. Navier-Stokes equation is employed to calculate the force due to the fluid in the pipe. As well, the effect of external fluid is modeled with an external force. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite. 1978 Tabas earthquake in Iran is considered for modelling seismic load. The dynamic displacement of the structure is extracted using differential quadrature method (DQM) and Newmark method. The effects of different parameters such as SiO2 nanoparticles volume percent, boundary conditions, thickness to radius ratios, length to radius ratios, internal and external fluid pressure and earthquake intensity are discussed on the seismic response of the structure. From results obtained in this paper, it can be found that the dynamic response of the pipe is increased in the presence of internal and external fluid. Furthermore, the use of SiO2 nanoparticles in concrete pipeline reduces the displacement of the structure during an earthquake.

• KSBB Journal
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• 제22권6호
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• pp.414-420
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• 2007

지금까지 우리는 몇 가지 나노입자에 대한 박테리아를 이용한 독성평가 및 탐지 연구 사례를 보았다. 이들은 주로 세포의 생장과 관련하여, 그 평가가 이루어졌고, silver nanoparticles과 같이 그 메커니즘을 밟히기 위해 좀 더 진행이 된 것 또한 있었다. 그러나 아직 그 연구 수준은 매우 미비한 상태이다. 위에서 살펴 본 대부분의 나노입자의 경우 산화적 손상과 밀접한 관련이 있어 보인다. 이것은 나노입자로부터 발생할 이온들에 의해 혹은 나노입자가 박테리아와 작용하여 세포막표면에 직접 달라붙는 현상들에 의해, 일어나는 것이 아닌가 하는 생각을 하게 한다. 그리고 이러한 결과들을 통하여, 나노입자의 독성 경로를 어느 정도 예측할 수 있을 것이다. 확실히 밝혀내지 못한 이러한 독성 경로에 대한 연구가 더 활발히 진행되어야 할 것이다. 나노물질의 많은 장점으로 인하여, 이미 많은 항균성 나노물질이 생산되어 이용되었지만 앞으로 새롭게 합성될 숫자는 우리가 예상할 수 없을 만큼 늘어날 것이라고 생각한다. 그리고 우리는 이들의 무분별한 사용으로 인한 부작용에 다시 한번 놀라게 될 것이고, 그들의 독성에 대해서 걱정할 것이다. 우리는 이들 나노물질에 대해서 단순한 세포 생장 연구를 벗어나, 그 독성 메커니즘을 밝히는 연구 또한 동시에 진행해야 할 것이다. 그것은 동물이나 사람세포의 독성경로 파악에도 유용한 정보를 제공할 수 있고, 나노물질의 이용으로 인한 폐해를 막을 수 있는 중요한 방법이 될 수 있는 것이다.

• 한국산업보건학회지
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• 제28권1호
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• pp.1-17
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• 2018

Objectives: This research is part of a study to be conducted over five years starting from 2017 by the Ministry of Environment on the development of technologies to evaluate the impact of chemical accidents on the human body. Methods: For this research, a five-stage specific study method was developed. Results: In brief, the developed health risk assessment method can be summarized as follows. First, a health risk assessment system was built based on the guidelines set forth by the USA NRC/NAS. Second, based on the disease manifestation theory, the health risk assessment method was divided into 1) a carcinogenic health risk assessment method focused on all carcinogens except non-genotoxic carcinogens and 2) a non-carcinogenic health risk assessment method focused on noncarcinogens including non-genotoxic carcinogens. Third, the detailed contents of the health risk assessment method were developed in four stages(hazard identification, dose-response assessment, exposure assessment, and risk determination) through theoretical consideration of the assessment of the level of health risk related to chemical exposure. Finally, a health risk assessment methodology, classified into stages to address acute, subacute/subchronic, and chronic conditions was developed after considering the physicochemical behavior of hazardous chemicals upon implementation of countermeasures after a chemical accident. Conclusions: A method to evaluate the health risks related to toxic chemicals generated by chemical accidents was developed. This study was performed with the purpose of developing a mathematical health risk assessment method to evaluate the health effects of exposure to hazardous chemicals upon implementation of emergency countermeasures after chemical accidents.