• Journal of Digestive Cancer Research
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• v.4 no.1
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• pp.1-9
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• 2016

The abundance of multi-drug resistance ATPase binding cassette and deranged self-renewal pathways shown in cancer stem cells (CSCs) played a crucial role in tumorigenesis, tumor resistance, tumor recurrence, and tumor metastasis. Therefore, elucidation of CSCs biology can improve diagnosis, enable targeted treatment, and guide the follow up of GI cancer patients. In order to achieve chemoquiescence, seizing cancer through complete ablation of CSCs, CSCs are rational targets for the design of interventions that will enhance responsiveness to traditional therapeutic strategies and contribute in the prevention of local recurrence as well as metastasis. However, current cancer treatment strategies fail to either detect or differentiate the CSCs from their non-tumorigenic progenies mostly due to the absence of specific biomarkers and potent agents to kill CSCs. Recent advances in knowledge of CSCs enable to produce several candidates to ablate CSCs in gastrointestinal (GI) cancers, especially cancers originated from inflammation-driven mutagenesis such as Barrett's esophagus (BE), Helicobacter pylori-associated gastric cancer, and colitis-associated cancer (CAC). Our research teams elucidated through revisiting old drugs that proton pump inhibitor (PPI) and potassium competitive acid blocker (p-CAB) beyond authentic acid suppression, chloroquine for autophage inhibition, sonic hedgehog (SHH) inhibitors, and Wnt/β-catenin/NOTCH inhibitor can ablate CSCs specifically and efficiently. Furthermore, nanoformulations of these molecules could provide an additional advantage for more selective targeting of the pathways existing in CSCs just like current molecular targeted therapeutics and sustained action, while normal stem cells intact. In this review article, the novel approach specifically to ablate CSCs existing in GI cancers will be introduced with the introduction of explored mode of action.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.88-88
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• 2022

Detection of stress responses in crops is important to diagnose crop growth and evaluate yield. Also, the multi-spectral sensor is effectively known to evaluate stress caused by nutrient and moisture in crops or biological agents such as weeds or diseases. Therefore, in this experiment, multispectral images were taken by an unmanned aerial vehicle(UAV) under field condition. The experiment was conducted in the long-term fertilizer field in the National Institute of Crop Science, and experiment area was divided into different status of NPK(Control, N-deficiency, P-deficiency, K-deficiency, Non-fertilizer). Total 11 vegetation indices were created with RGB and NIR reflectance values using python. Variations in nutrient content in plants affect the amount of light reflected or absorbed for each wavelength band. Therefore, the objective of this experiment was to evaluate vegetation indices derived from multispectral reflectance data as input into machine learning algorithm for the classification of nutritional deficiency in rice. RandomForest model was used as a representative ensemble model, and parameters were adjusted through hyperparameter tuning such as RandomSearchCV. As a result, training accuracy was 0.95 and test accuracy was 0.80, and IPCA, NDRE, and EVI were included in the top three indices for feature importance. Also, precision, recall, and f1-score, which are indicators for evaluating the performance of the classification model, showed a distribution of 0.7-0.9 for each class.

• Pediatric Infection and Vaccine
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• v.31 no.1
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• pp.140-146
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• 2024

Multisystem inflammatory syndrome in children (MIS-C) is a rare complication of coronavirus disease 2019 (COVID-19), causing multi-organ damage affecting the heart, lungs, kidneys, digestive tract, and nervous system. As the cases of MIS-C have been increasing following the COVID-19 pandemic, the importance of appropriate management for MIS-C is becoming increasingly apparent. Immunomodulating agents such as anakinra, infliximab, and steroids are regarded as supplementary therapy to the first-line treatment with intravenous immunoglobulin. However, these immunomodulating therapies can potentially precipitate opportunistic infections, including those caused by cytomegalovirus (CMV), Epstein-Barr virus, and tuberculosis, or increase the risk of co-infections. Herein, we report a case of a 3-year-old boy who was treated with immunoglobulin, infliximab, and high-dose methylprednisolone for MIS-C, and subsequently developed a persistent fever lasting 32 days caused by a CMV infection.

• Journal of Veterinary Clinics
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• v.34 no.5
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• pp.335-340
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• 2017

Methicillin-resistant staphylococci (MRS), which are often multi-drug resistant (MDR), are important pathogens in both human and veterinary healthcare. The purpose of this study was to characterize the antimicrobial resistance of MRS isolated from dog ears in Korea. From 827 dog ears, staphylococci were cultured from both ears with otitis externa (n = 161, 41.0%) and healthy ears (n = 135, 31.1%). The prevalence of coagulase-positive staphylococci (CoPS) in ears with otitis externa (58.4%) was significantly higher (p < 0.05) than in healthy ears (28.2%), while the prevalence of coagulase-negative staphylococci (CoNS) in healthy ears (74.8%) was higher (P < 0.05) than in ears with otitis externa (41.6%). Forty-six (35.1%) and 74 (44.8%) CoPS and CoNS isolates, respectively, were determined to be MRS. Antimicrobial resistance in MRS was most frequently observed for penicillin (76.7%), ampicillin (61.7%), kanamycin (61.7%), erythromycin (47.5%), tetracycline (47.5%), and trimethoprim/sulfamethoxazole (46.7%). Overall, the MDR isolates were resistant to significantly more (P < 0.05) antimicrobial agents tested than methicillin-sensitive staphylococci in this study. These results provide therapeutic guidelines for the treatment of otitis externa in dogs from Korean veterinary hospitals, and the significant associated health concern to companion animals and their human contacts.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2002.11a
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• pp.363-369
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• 2002

가정 내에서의 초고속망 이용이 활성화되면서 가정 내에서의 활동은 매우 다양하고 복잡하며 그에 따른 서비스도 여러 가지 형태가 존재한다. 외부 인터넷망과 연동되는 홈 네트워크의 개념이 생기기 전부터 흠 오토메이션, 홈시큐리티 등의 서비스를 제공하기 위한 고립적인 형태의 망과 서비스 제공 시스템이 있었다. 월드 와이드 웹 서비스를 기본으로 한 인터넷의 폭발적인 활성화와 고속 인터넷망의 확산에 따라 가정 내에서 제공되는 서비스를 인터넷과 연계시키려는 시도가 보편화되었고 가정 내에서 사용되는 독립적인 기기들을 인터넷에 연결하여, 외부의 정보를 이용해서 활용하거나, 가전내의 기기들을 외부에서 액세스할 수 있게 되었다. 이렇게 하여 보다 풍부한 서비스를 제공하고, 사용상의 시간적인 제약을 완화할 수 있다. 예들 들어 인터넷상에서 조리법을 전송받아 전자레인지를 작동할 수 있으며, 외부에서 잘못 켜둔 가스밸브를 잠글 수도 있다. 가정 내에서 wrhd되던 이러한 서비스들은 서로 다른 하드웨어와 통신방법을 사용하고 있어, 이러한 서비스를 통합하여 운영, 관리할 수 있도록 하는 흠 서버의 개념이 대두되었다. 외부 인터넷 망과 연계된 흠 오토메이션, 홈 시큐리티등을 제공할 수 있는 기반이 마련되었고, 가정 내에서 독립적으로 제공되던 서비스들을 단일 홈 서버를 통해서 관리하려는 시도가 진행되었다. 그러나 홈 서버는 개발하는 업체의 보유기술에 따라 중심기능은 약간씩 차이를 보이고 있다. 홈 서버 응용 영역은 전문 지식을 소유한 인력과의 연계가 필요하고, 다양한 서비스 영역 행위가 아주 복잡하기 때문에 이들을 연결해 주는 자치 시스템을 필요로 한다. 또한 홈 서버 서비스 영역에서 정보는 각 영역 전문가가 가진 지식의 전달을 필요로 하기 때문에, 지식을 주고받는 멀티 에이전트의 시스템의 활용 영역으로 적당하다. 멀티 에이전트 시스템은 분산된 환경에서 에이전트간에 에이전트 통신 언어를 사용해서 대화를 하기도 하고, 상호 협력하는 에이전트들로 구성된 시스템을 뜻하며 흠 서버처럼 동적이고 고도의 자치성을 요구하는 영역에 적당하다. 멀티 에이전트 플랫폼으로는 FIPA(Foundation for Intelligent Physical Agents)가 제시한 에이전트 표준 플랫폼이 1997년부터 2000년에 이르기까지, 계속적으로 변화, 발전하고 있다. 본 연구는 FIPA에서 제시하는 플랫폼을 기반으로 홈 서버에 정보가전을 제어하는 에이전트를 두고 외부에서 다른 에이전트가 홈 서버에 위치하는 에이전트와의 통신을 통하기 정보가전을 지능적으로 제어하도록 하였다. 정보가전 에이전트는 가정 내 가전제품을 외부에서 제어하기 위한 에이전트이다. 단순한 관리가 아닌 에이전트로 하여금 지능적으로 가전제품 관리를 하게 한다. 정보가전 에이전트는 홈 서버에서 작동하는 에이전트와 PDA에서 작동하는 에이전트로 구성된다. 정보가전 에이전트는 전력량, 수도 사용량 제어와 가전제품 제어 기능과 보안 관련 서비스를 제공한다. 두 에이전트는 FIPA에서 정의된 규격에 맞게 만들어지기 때문에 FIPA명세서를 따르는 다른 에이전트와 자유로운 통신이 가능하다.

• Korean Journal of Medicinal Crop Science
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• v.21 no.1
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• pp.7-19
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• 2013

This study was carried out to select new pelleting binder and material for seeds from Fraxinus rhynchophylla Hance and Alnus sibirica Fisch. ex Turcz. The optimum treatments of the various concentrations and species of priming agents to improve seed germination of both woody medicinal plants were also estimated. Germinability was increased when the seeds of Fraxinus rhynchophylla Hance was soaked in -1.0 MPa of PEG6000 solution at $15^{\circ}C$ for 4 days significantly, the optimum treatment for improving germination of Alnus sibirica Fisch. ex Turcz was observed when the tested seeds was soaked in 100 mM of KCl at $15^{\circ}C$ for 4 days. The influence of physical and chemical properties of pelleting solid materials, the mixture of gypsum, diatomaceous earth, dalma ceramic and vermicuolite (6:1:1:1 ratio) were found as the best pelleting materials for Fraxinus rhynchophylla Hance and Alnus sibirica Fisch. ex Turcz. seeds. To satisfy the requirements of absorption and compatibility for multi-layer seed pelleting, SGPA (Starch-grafted cross-linked polyacrylates) hydrogel was prepared using starch, acrylonitrile, ceric ammonium nitrate, nitric acid, methyl alcohol and potassium hydroxide. The resulting SGPA hydrogel showed high water absorption but not plant compatibility. It suggested that seed pelleting using pelleting materials and SGPA hydrogel (multi-layer coating) after priming agent treatment is to increase germinability and seedling growth and it can reduced irrigation labours and can also save seed.

• Journal of the Korean Geographical Society
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• v.36 no.1
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• pp.35-51
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• 2001

Social historical geography is interested in geographical elements related with a social group and perceives the diverse dimensions of a geographical phenomenon. The purpose of this study is to examine and interpret the multi-layers of meanings associated with the ancestral places of lineage group, i.e. Bonkwans(本貫)in Korea with a viewpoint to social historical geography. The term Bonkwan does not appear in any historical records prior to ths 10th century. Thereafter it is used continuoushy by lineage groups or by govermment agents till the 17th century. I believe that during this long-term period Bonkwan assumed multiple geographical meanings which varied from period to period, such as residence place, a place of origin, and a place symbolizing power. Each layer of meaning was the product of a certain period and of a cetain lineage. Its first meaning was produced in the early Koryo kingdom. Its second meaning from late in the same kingdom to the early part of Chosun kingdom. In order to understand the meaning of Bonkwan correctively, we need to see it at a large perspective. That is to say, it needs to be viewed in the framework of immigration study of each lineage because the term is more is moreof a social construct than a fixed notion.

• Applied Chemistry for Engineering
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• v.24 no.1
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• pp.31-37
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• 2013

Lowering surface reflectance of Si wafers by texturization is one of the most important processes for improving the efficiency of Si solar cells. This paper presents the results on the effect of texturing using acidic solution mixtures containing the catalytic agents to moderate etching rates on the surface morphology of mc-Si wafer as well as on the performance parameters of solar cell. It was found that the treatment of contaminated crystalline silicon wafer with $HNO_3-H_2O_2-H_2O$ solution before the texturing helps the removal of organic contaminants due to its oxidizing properties and thereby allows the formation of nucleation centers for texturing. This treatment combined with the use of a catalytic agent such as phosphoric acid improved the effects of the texturing effects. This reduced the reflectance of the surface, thereby increased the short circuit current and the conversion efficiency of the solar cell. Employing this technique, we were able to fabricate mc-Si solar cell of 16.4% conversion efficiency with anti-reflective (AR) coating of silicon nitride film using plasma-enhanced chemical vapor deposition (PECVD) and Si wafers can be texturized in a short time.

• Journal of Adhesion and Interface
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• v.16 no.4
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• pp.137-145
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• 2015

This study aimed to develop epoxy putty as a multi-purpose connection and restoration material that can be used for material-specific restoration work such as metal, wood, ceramics, earthenware and stone artifacts by replacing synthetic resins currently being used for preservation treatment of cultural assets. Existing synthetic resins have the issue of cutting force resulting from high strength, deflection resulting from long hardening time, contaminating the surface of artifacts through staining on tools or gloves and need for re-treatment resulting from material discoloration. Accordingly, paste type restoration material most widely being used in the field of cultural assets preservation treatment was selected and examined the property to select it as an object of comparison. Based on such process, epoxy putty was developed according to the kind of agent, hardener and filler. For the purpose of solving the issues of existing material and allowing the epoxy putty developed to have similar property, property experiments were conducted by selecting agents and hardeners with different characteristics and conditions. The study findings showed that both kinds are paste type that improved work convenience and deflection issue as a result of their work time of within 5~10 minutes that are about 3~10 times shorter than that of existing material. In regards to wear rate for increasing cutting force, it improved by about 3 times, thereby allowing easy molding. For the purpose of improving the issue of surface contamination that occurs during work process, talc and micro-ballon were added as filler to reduce the issue of stickiness and staining on hand. Furthermore, a multi-purpose restoration material with low shrinkage, low discoloration and high cutting force was developed with excellent coloring, lightweight and cutting force features.

• Journal of the Korean Society of Safety
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• v.11 no.2
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• pp.150-159
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• 1996

In this paper, an A-team(Asynchronous Team ) based approach for Reactive power and volage control considering static security assessment in a power system with infrastructural deficiencies is proposed. Reactive power and voltage control problem is the one of optimally establishing voltage level given several constraints such as reactive generation, voltage magnitude, line flow, and other switchable reactive power sources. It can be formulated as a mixed-integer linear programming(MILP) problem without deteriorating of solution accuracy to a certain extent. The security assessment is to estimate the relative robustness of the system in Its present state through the evaluation of data provided by security monitoring. Deterministic approach based on AC load flow calculations is adopted to assess the system security, especially voltage security. A security metric, as a standard of measurement for power system security, producting a set of discrete values rather than binary values, is employed. In order to analyze the above two problems, reactive power/voltage control problem and static security assessment problem, in an integrated fashion for real-time operations, a new organizational structure, called an A-team, is adopted. An A-team is an organization for agents which ale all autonomeus, work in parallel and communicate asynchronously, which is well-suited to the development of computer-based, multi-agent systems for operations. This A-team based approach, although it is still in the beginning stage, also has potential for handling other difficult power system problems.