• Molecules and Cells
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• v.44 no.5
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• pp.356-362
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• 2021

An increasing number of studies have revealed an interaction between gut microbiota and tumors. The enrichment of specific bacteria strains in the intestines has been found to modulate tumor growth and influence the mechanisms of tumor treatment. Various bacteria are involved in modulating the effects of chemotherapeutic drugs currently used to treat patients with cancer, and they affect not only gastrointestinal tract tumors but also distant organ tumors. In addition, changes in the gut microbiota are known to be involved in the antitumor immune response as well as the modulation of the intestinal immune system. As a result, the gut microbiota plays an important role in modulating the efficacy of immune checkpoint inhibitors. Therefore, gut microbiota could be considered as an adjuvant treatment option with other cancer treatment or as another marker for predicting treatment response. In this review, we examine how gut microbiota affects cancer treatments.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.465-475
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• 2015

The purpose of this study is to analyze the results of physics (optics) in nationwide standardized assessment and to investigate middle-school students' characteristics of achievement by using an option response rate distribution curve. For this purpose, we analyzed the 10 optics problems from the National Assessment of Educational Achievement (NAEA) items for middle school science subject conducted in 2010-2013. The results of this study are as follows; First, students showed a little higher achievement in optics than classical mechanics and electromagnetism. Second, students achieved significantly worse in 'formation of image' in 'light' part and 'variation of phase in propagation of wave' in 'wave' part. Third, students showed a context-dependent problem solving strategy and result. Additionally, we suggested some implications about the readjustment of some optics concepts level of national science curriculum, the need for teaching and learning strategies for basic level students, and the need for teaching and learning strategies focused on the realistic context.

• New & Renewable Energy
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• v.7 no.2
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• pp.18-27
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• 2011

Management flexibility to adapt its future actions in response to altered future market conditions can expand the value of an investment opportunity by improving its upside potential without the change in the downside losses. Module manufacturers in solar industry continuously have to decide how much and when its production capacity should be expanded with regards to the demand in the global markets. Either over- or under-investment can cause sunk and/or opportunity costs to the module manufacturers. Option of exercising the additional investments only on favorable opportunities can increase total value of the investment. This paper analyzes the case which shows that the expansion of production capacity with more expandibility can have more value than the rigid plan of capacity expansion. The expansion option value is equivalent to KRW 38.286 billion, thus switching the negative NPV of the initial investment opportunity into the positive value. High volatility and the high growth in the cashflows as the major business features of the renewable energy provide condition where real options can play the crucial role in increasing the investment value as well as in determining the size and timing of capacity expansion in the course of capital budgeting process.

• Korean Management Science Review
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• v.31 no.2
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• pp.71-86
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• 2014

There is a growing need for technology transactions between the technology providers, who develop technologies, and the technology consumers, who purchase and commercialize technologies, to be smooth, when technologies, as intangible assets, are traded as items that can be purchased and sold. In response to these challenges, this study examines new approaches to assessing the fair market value of technologies. Because corporations are the main force behind technology development and commercialization in the existing business environment, applying one valuation method to technology assets is viable; however, as the subjects of technology development and technology commercialization are separate, the need for price negotiations between the subjects of technology transaction has grown. Moreover, as the investigations into and the application of transaction prices have been performed separately by technology providers, technology consumers, and technology assessment financial institutions, the research on technology valuation methods has shown that there are differences in perceived transaction prices between the subjects involved. This research presents a new method, appropriate to technology transactions; unlike existing methods, it grants option values to the technology provider and newly defined key variables to the technology consumer.

• Environmental and Resource Economics Review
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• v.14 no.3
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• pp.753-773
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• 2005

This paper is a study of the investment dynamics focusing on crude oil supply by OPEC and non-OPEC. Oil supply capacity is first determined by a leader, OPEC, and by an aggregate that represents non-OPEC producers. OPEC wants to increase a gain from oil price increase while keeping its market share relative to non-OPEC's share. An investment rule model is developed for OPEC crude oil supply capacity in response to non-OPEC's decision. In presence of oil price uncertainty, oil price threshold is derived above which it is optimal for OPEC to expand oil supply capacity since otherwise the increased supply of non-OPEC results in weakening of OPEC market share in the world oil market. In addition, a lower threshold price is derived below which OPEC triggers a capacity reduction to regain its otherwise forgone profits. A simulation is provided for calculating the capacity expansion and reduction thresholds.

• Radiation Oncology Journal
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• v.34 no.3
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• pp.168-176
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• 2016

Purpose: The purpose of current study is to evaluate the response of the patients with portal vein thrombosis (PVT) or hepatic vein thrombosis (HVT) in hepatocellular carcinoma (HCC) treated with three-dimensional conformal radiation therapy (3D-CRT). In addition, survival of patients and potential prognostic factors of the survival was evaluated. Materials and Methods: Forty-seven patients with PVT or HVT in HCC, referred to our department for radiotherapy, were retrospectively reviewed. For 3D-CRT plans, a gross tumor volume (GTV) was defined as a hypodense filling defect area in the portal vein (PV) or hepatic vein (HV). Survival of patients, and response to radiation therapy (RT) were analyzed. Potential prognostic factors for survival and response to RT were evaluated. Results: The median survival time of 47 patients was 8 months, with 1-year survival rate of 15% and response rate of 40%. Changes in Child-Pugh score, response to RT, Eastern cooperative oncology group performance status (ECOG PS), hepatitis C antibody (HCVAb) positivity, and additional post RT treatment were statistically significant prognostic factors for survival in univariate analysis (p = 0.000, p = 0.018, p = 0.000, p = 0.013, and p = 0.047, respectively). Of these factors, changes in Child-Pugh score, and response to RT were significant for patients' prognosis in multivariate analysis (p = 0.001 and p = 0.035, respectively). Conclusion: RT could constitute a reasonable treatment option for patients with PVT or HVT in HCC with acceptable toxicity. Changes in Child-Pugh score, and response to RT were statistically significant factors of survival of patients.

• Clinical Endoscopy
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• v.55 no.6
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• pp.784-792
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• 2022

Background/Aims: Patients with acute cholecystitis (AC) after metallic stent (MS) placement for malignant biliary obstruction (MBO) have a high surgical risk. We performed percutaneous transhepatic gallbladder aspiration (PTGBA) as the first treatment for AC. We aimed to identify the risk factors for AC after MS placement and the poor response factors of PTGBA. Methods: We enrolled 401 patients who underwent MS placement for MBO between April 2011 and March 2020. The incidence of AC was 10.7%. Of these 43 patients, 37 underwent PTGBA as the first treatment. The patients' responses to PTGBA were divided into good and poor response groups. Results: There were 20 patients in good response group and 17 patients in poor response group. Risk factors for cholecystitis after MS placement included cystic duct obstruction (p<0.001) and covered MS (p<0.001). Cystic duct obstruction (p=0.003) and uncovered MS (p=0.011) demonstrated significantly poor responses to PTGBA. Cystic duct obstruction is a risk factor for cholecystitis and poor response factor for PTGBA, whereas covered MS is a risk factor for cholecystitis and an uncovered MS is a poor response factor of PTGBA for cholecystitis. Conclusions: The onset and poor response factors of AC after MS placement were different between covered and uncovered MS. PTGBA can be a viable option for AC after MS placement, especially in patients with covered MS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.254-257
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• 2018

In this paper, we implement the mobile application for disaster and safety accident response that can be easily accessed through smart phones to prevent the loss of life and poor awareness of safety to the increased number of disasters and accidents. A few of related mobile applications for accident response are served, and the most of them have the manual interfaces. In this paper, we implement the mobile application for scenario of the disaster such as earthquake and safety accident that can occur in daily life. It is organized in a form of a clear action option with user-friendly visual characters and can be used regardless of age group.

• The Journal of Internal Korean Medicine
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• v.44 no.3
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• pp.562-577
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• 2023

Objectives: This is a five-year survival and complete response (CR) report on pancreatic cancer treated with western medicine and Korean traditional medicine. Method: A 59-year-old woman diagnosed with pancreatic cancer visited ○○ Korean traditional medicine hospital after neoadjuvant chemotherapy and pylorus-preserving pancreaticoduodenectomy. She was treated with Korean traditional medicine, including acupuncture, abdominal moxibustion, wild ginseng pharmacopuncture, and herbal medicine, which was based on integrated medicine therapy (IMT), from March 2018 to September 2022. The tumor size was measured by scanning with computed tomography (CT), magnetic resonance imaging, and positron-emission tomography/CT. Adverse events were evaluated using laboratory conclusion and National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0. Result: During four years and three months of treatment, IMT maintained safety. The patient finally reached five-year survival without any recurrence or complication (CR) on October 26, 2022. Conclusion: We suggest that an integrative approach including Korean traditional medicine can be a meaningful treatment option for pancreatic cancer. Further studies should be performed to establish the proper treatment protocol of integrative medicine for pancreatic cancer.

• Earthquakes and Structures
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• v.11 no.2
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• pp.217-243
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• 2016

The linear and nonlinear seismic responses of steel buildings with perimeter moment resisting frames and welded connections (WC) are estimated and compared with those of buildings with post-tensioned connections (PC). Two-dimensional (2D) and three-dimensional (3D) structural representations of the buildings as well as global and local response parameters are considered. The seismic responses and structural damage of steel buildings with PC may be significantly smaller than those of the buildings with typical WC. The reasons for this are that the PC buildings dissipate more hysteretic energy and attract smaller inertia forces. The response reduction is larger for global than for local response parameters. The reduction may significantly vary from one structural representation to another. One of the main reasons for this is that the energy dissipation characteristics are quite different for the 2D and 3D models. In addition, in the case of the 3D models, the contribution of each horizontal component to the axial load on an specific column may be in phase each other during some intervals of time, but for some others they may be out of phase. It is not possible to observe this effect on the 2D structural formulation. The implication of this is that 3D structural representation should be used while estimating the effect of the PC on the structural response. Thus, steel frames with post-tensioned bolted connections are a viable option in high seismicity areas due to the fact that brittle failure is prevented and also because of their reduced response and self-centering capacity.