• Toxicological Research
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• 제32권1호
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• pp.21-33
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• 2016

Dichlorodiphenyltrichloroethane (DDT) is still used in certain areas of tropics and subtropics to control malaria and other insect-transmitted diseases. DDT and its metabolites have been extensively studied for their toxicity and carcinogenicity in animals and humans and shown to have an endocrine disrupting potential affecting reproductive system although the effects may vary among animal species in correlation with exposure levels. Epidemiologic studies revealed either positive or negative associations between exposure to DDT and tumor development, but there has been no clear evidence that DDT causes cancer in humans. In experimental animals, tumor induction by DDT has been shown in the liver, lung, and adrenals. The mechanisms of hepatic tumor development by DDT have been studied in rats and mice. DDT is known as a non-genotoxic hepatocarcinogen and has been shown to induce microsomal enzymes through activation of constitutive androstane receptor (CAR) and to inhibit gap junctional intercellular communication (GJIC) in the rodent liver. The results from our previously conducted 4-week and 2-year feeding studies of p,p'-DDT in F344 rats indicate that DDT may induce hepatocellular eosinophilic foci as a result of oxidative DNA damage and leads them to hepatic neoplasia in combination with its mitogenic activity and inhibitory effect on GJIC. Oxidative stress could be a key factor in hepatocarcinogenesis by DDT.

• The Korean Journal of Pain
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• 제8권1호
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• pp.164-167
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• 1995

대상포진후 신경통으로 체성신경 차단과 함께 성상신경절 차단을 반복적으로 받아오던 64세 여자환자에서 열세번째 우측 성상신경절 차단후 반대측인 좌측에 호너씨 증후군이 발생되었다. 그 원인은 명확하지 않지만 시술 도중 환자머리의 좌측회전으로 인한 해부학적 위치변화와 술자의 부정확한 지표선정 및 주사바늘의 안쪽방향등으로 약제가 중앙선을 넘어 주입된 것으로 추정할수 있다.

• 방사성폐기물학회지
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• 제18권3호
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• pp.337-346
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• 2020

Two commonly used ceramics in molten salt research are alumina and mullite. The two ceramics were exposed to a combination of rare earth chlorides (YCl₃, SmCl₃, NdCl₃, PrCl₃, and CeCl₃; each rare earth chloride of 1.8 weight percent) in LiCl-KCl at 773 K for approximately 13 days. Scanning electron microscopy with wave dispersion spectra was utilized to investigate a formation layer or deposition of rare earths onto the ceramic. Only the major constituents of the ceramics (Al, Si, and O₂) were observed during the wave dispersion spectra. X-ray fluorescence was used as well to determine concentration changes in the molten salt as a function of ceramic exposure time. This study shows no evidence of ionic exchange or layer formation between the ceramics and molten chloride salt mixture. There are signs of surface tension effects of molten salt moving out of the tantalum crucible into secondary containment.

• 한국식생활문화학회지
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• 제19권5호
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• pp.556-565
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• 2004

This study examined dietary culture in Korea regarding collectivism through literature review. Based on the evidence from the origin of lineage and traditional customs, the Koreans' traditional collectivity appeared to have been grounded upon the northen nomadic culture emphasizing sentimental collectivity and harmonized with the characteristics of southern agrarian society related to mutual support and sociability. The inseparable relationship between collectivity and food was well revealed in the occasions such as rice-planting, kimchi and jang makings in which pooled labor was common as well as the gathering of mutual aid association. In these occasions, foods were offered and shared among members. Food sharing was a main activity and almost play a central role regarding the promotion of friendly relations among each other. In sacrificial memorials, food sharing was extended not only to the live persons but also to the passing spirits. Collectivity was also disclosed in the eating or table manners of Koreans. Koreans quite literally share food at every meal since the side dishes placed centrally on the table. The taste of Korean foods is completed inside the mouth by mixing foods with various combination, which let people create their own choice of taste. Therefore, the collectivity manners at the table appeared to be harmonized with individual freedom of creating his/her own taste of foods. The collectivity is still a very important concept in modem Korean dietary culture, as reflected by an increase of restaurants sewed shared dishes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 B
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• pp.606-608
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• 1997

In this paper, Neuro-Fuzzy Controller(NFC), a fuzzy system realized using a neural network, is to adopt for the multivariable system. In the multivariable system, the interactive effects between the variables should be taken into account. A simple compensator, using the steady-state information can be obtained for open-loop stable systems, is presented to cope with this problem. However, it should be supposed that the plant is unknown to the control system designer, but an estimate of the DC gain has been obtained by carrying out experiments on the plant. Also, if the variables are not combinated completely, it is difficult to design the controller. Therefore, we design a neuro-fuzzy controller which controls a multivariable system with only input output informations, and compare its performance with that of a PI controller. In the proposed controller, the construction of the membership functions and rule base, which is highly heuristic, can be achieved using a training process. This allows the combination of knowledge of human experts and evidence from input-output data.

• 한국환경교육학회지:환경교육
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• 제19권3호
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• pp.150-164
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• 2006

This study reviewed a recently developed environmental education model 'ENVISION' and analyzed the value of the ENVISION program with environmental education(EE) perspective. Also this study proposed a prototype model of a inquiry-based water environmental education model with watershed concepts as a result of discussion of tills research. In the review of ENVISION, this research followed the theoretical framework of 'Inquiry-Based EE' that was previously proposed by the author. The ENVISION was characterized in tills research as two directions: watershed and scientific inquiry. Tills research argued that the watershed concept has a potentially very good meaning in EE because watershed enables 'holistic' view in EE area, and that the scientific inquiry in ENVISION seeks evidence-based explanation about local watershed environmental problems. That belongs to the scientific inquiry, which is also 'Inquiry-Based EE' and has internal value under EE perspective. Finally, this research proposed a prototype EE model that is about watershed concept, and is based on inquiry as general sense (scientific and insightful inquiries) and 'Environmental Studies for EE, (ESEE)' as the inquiry directions. The proposed model can be said a combination of the watershed concept and inquiry-based EE, and it seems that the model materializes better the EE nature than the ENVISION model.

• 한국가금학회지
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• 제38권2호
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• pp.155-164
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• 2011

The use of antimicrobials will be soon removed due to an increase of occurrence of antibiotic-resistant bacteria or ionophore-resistant Eimeria species in poultry farms and consumers' preference on drug-free chicken meats or eggs. Although dietary antimicrobials contributed to the growth and health of the chickens, we do not fully understand their interrelationship among antimicrobials, gut microbiota, and host immunity in poultry. In this review, we explored the current understanding on the effects of antimicrobials on gut microbiota and immune systems of chickens. Based on the published literatures, it is clear that antibiotics and antibiotic ionophores, when used singly or in combination could influence gut microbiota. However, antimicrobial effect on gut microbiota varied depending on the samples (e.g., gut locations, digesta vs. mucosa) used and among the experiments. It was noted that the digesta vs. the mucosa is the preferred sample with the results of no change, increase, or decrease in gut microbiota community. In future, the mucosa-associated bacteria should be targeted as they are known to closely interact with the host immune system and pathogen control. Although limited, dietary antimicrobials are known to modulate humoral and cell-mediated immunities. Ironically, the evidence is increasing that dietary antimicrobials may play an important role in triggering enteric disease such as gangrenous dermatitis, a devastating disease in poultry industry. Future work should be done to unravel our understanding on the complex interaction of host-pathogen-microbiota-antimicrobials in poultry.

• Radiation Oncology Journal
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• 제38권1호
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• pp.1-10
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• 2020

Radiotherapy (RT) has been used for decades as one of the main treatment modalities for cancer patients. The therapeutic effect of RT has been primarily ascribed to DNA damage leading to tumor cell death. Besides direct tumoricidal effect, RT affects antitumor responses through immune-mediated mechanism, which provides a rationale for combining RT and immunotherapy for cancer treatment. Thus far, for the combined treatment with RT, numerous studies have focused on the immune checkpoint inhibitors and have shown promising results. However, treatment resistance is still common, and one of the main resistance mechanisms is thought to be due to the immunosuppressive tumor microenvironment where myeloid-derived suppressor cells (MDSCs) play a crucial role. MDSCs are immature myeloid cells with a strong immunosuppressive activity. MDSC frequency is correlated with tumor progression, recurrence, negative clinical outcome, and reduced efficacy of immunotherapy. Therefore, increasing efforts to target MDSCs have been made to overcome the resistance in cancer treatments. In this review, we focus on the role of MDSCs in RT and highlight growing evidence for targeting MDSCs in combination with RT to improve cancer treatment.

• 한국간호교육학회지
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• 제24권4호
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• pp.376-390
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• 2018

Purpose: The purpose of this study was to (a) synthesize nursing education literature using a smartphone for Korean nursing college students based on Whittemore and Knafl's integrative five-step review method and to (b) evaluate the quality appraisal of each article using Gough's weight of evidence. Methods: Articles published in Korea were identified through electronic search engines and scholarly websites using a combination of three search terms, including nursing student, smartphone, and education. Scientific, peer-reviewed articles in nursing education for Korean college nursing students, written in Korean or in English, and published between January 2000 and May 2018 were included in this review. Thirteen papers met the inclusion criteria and had above average ratings in quality appraisals. Results: Three characteristics related to nursing education using a smartphone were derived: (a) as a familiar media, motivating learning and enabling self-directed learning, (b) for the purpose of education or evaluation utilizing the educational movie of application, and (c) the iterative exercise of smartphone usage reinforces student learning. Conclusion: Smartphone use is an effective tool for improving nursing knowledge and skills for nursing college students in nursing education. Future research is needed to standardize smartphone applications across schools for nursing education.

• 대한인간공학회지
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• 제23권1호
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• pp.1-12
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• 2004

The purpose of this study was to develop an automatic expert system for the evaluation of human sensibility, where human sensibility can be inferred from objective physiological signals. The study aim was also to develop an algorithm in which human arousal and pleasant level can be judged by using measured physiological signals. Fuzzy theory was applied for mathematical handling of the ambiguity related to evaluation of human sensibility. and the degree of belonging to a certain sensibility dimension was quantified by membership function through which the sensibility evaluation was able to be done. Determining membership function was achieved using results from a physiological signal database of arousal/relaxation and pleasant/unpleasant that was generated from imagination. To induce one final result (arousal and pleasant level) based on measuring the results of more than 2 physiological signals and the membership function of each physiological signal. Dempster-Shafer's rule of combination in evidence was applied, through which the final arousal and pleasant level was inferred.