• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.305-312
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• 2019

The discovery of nitric oxide (NO) as a major signaling molecule in a number of pathophysiological processes - vasodilation, immune response, platelet aggregation, wound repair, and cancer biology - has led to the development of various exogeneous NO delivery systems. However, the development of ideal delivery system for human body application is still left as a challenge due to its high reactivity and short half-life in physiological condition. In this article, an overview of several nano-structures as potential NO delivery system will be presented, along with their recent research results and biomedical applications. Nano-size delivery system has immense advantages compared to others due to its high surface-to-volume ratio and capability for surface modification; thus, it has been proven to be effective in delivering nitric oxide with enhanced performance. Through this novel nano-structure delivery system, we are expecting to achieve sustained release of nitric oxide within adequate range of concentration, which ensures desired drug effects at the target site. Among different nano-structures, in particular, nanoparticle, microemulsion and nanofilm will be reviewed and compared to each other in respect of nitric oxide release profile. The proposed nano-structures for exogeneous NO delivery have a biological significance in that it can be further utilized in diverse biomedical fields as a highly promising therapeutic method.

• The Journal of Korean Philosophical History
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• no.58
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• pp.307-336
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• 2018

This paper traces the historical genealogy of the subjectivity and the silsim (實心, true mind) that appear in Jeong In-Bo's "gukhak" (國學, the national learning) thought and illuminates its characteristics. In the modern East Asian history of thought, the beginning of the emergence of subjectivity and the silsim as the main philosophical topic comes from the Neo-Confucianism of Song Dynasty in China. Cheng Yi is the first thinker to emphasize subjectivity and consciousness. Zhu Xi and Wang Yang-ming inherit the Neo-Confucian thought based on Cheng Yi's principle of subjectivity, but only show difference in methodology. In the Chosun Dynasty, Jeong Je-Doo and his School were one example of the Neo-Confucian spirit of subjectivity and the silsim. Although Jeong In-Bo (鄭寅普) belongs to Jeong Je-Doo's school of Ganghwa in the school curriculum, he has only used it methodologically since he believed that Yangming's learning is more effective in the awareness and practice of the silsim. Especially noteworthy is that the principle of subjectivity led Jeong In-Bo to follow the frame of Zhu Xi's moral theory. Jeong's claim that selfish desire (jasasim 自私心) should be controlled by a conscious mind (silsim) being aware of the right and 'ought to do' corresponds to Zhu Xi's view that the moral mind (dosim 道心) should be selected in the conflict situation between sensual desire (insim 人心) and moral consciousness so that the insim should be supervised by the dosim. Such ethics is a position to emphasize the inner motive and the sense of duty of conduct, and there is no fundamental difference in Zhu Xi and Wang Yang-ming. At least on this point, it is necessary to look at modern and contemporary Korean studies from the perspective of continuity, not discontinuity from Confucian tradition.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.724-732
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• 2020

Phytophthora capsici is the organism that causes Phytophthora blight which infects red pepper plants prolifically, ultimately leading to crop loss. A previous study revealed that Enterobacter asburiae ObRS-5 suppresses Phytophthora blight in both red pepper and Ligularia fischeri plants. In order to determine whether the induced systemic resistance (ISR) was triggered by pre-infection with the ObRS-5 strain, we conducted quantitative PCR using primers for PR1, PR4, and PR10, which correlate with systemic resistance in red-pepper plants. In our results, red pepper plants treated with the ObRS-5 strain demonstrated increased expression of all three systemic resistance genes when compared to controls in the glasshouse seedling assay. In addition, treatment of red peppers with the ObRS-5 strain led to reduced Phytophthora blight symptoms caused by P. capsici, whereas all control seedlings were severely affected. Perhaps most importantly, E. asburiae ObRS-5 was shown to induce the ISR response in red peppers without inhibiting growth. These results support that the defense mechanisms are triggered by ObRS-5 strain prior to infection by P. capsici and ObRS-5 strain-mediated ISR action are linked events for protection to Phytophthora blight.

• Journal of Life Science
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• v.32 no.5
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• pp.375-390
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• 2022

Influenza viruses are zoonotic respiratory pathogens, and influenza infections have caused a substantial burden on public health systems and the livestock industry. Although currently approved seasonal influenza vaccines have shown potent protection efficacy against antigenically well-matched strains, there are considerable unmet needs for the efficient control of viral infections. Enormous efforts have been made to develop broadly protective universal influenza vaccines to tackle the huge levels of genetic diversity and variability of influenza viruses. In addition, antiviral drugs have been considered important interventions for the treatment of viral infections. The viral neuraminidase inhibitor oseltamivir is the most widely used antiviral medication to treat influenza A and influenza B viruses. However, unsatisfactory clinical outcomes resulting from side effects and the emergence of resistant variants have led to greater attention being paid to plants as a natural resource for anti-influenza drugs. In particular, the recent COVID-19 pandemic has underpinned the need for safe and effective antiviral drugs with a broad spectrum of antiviral activity to prevent the rapid spread of viruses among humans. This review outlines the results of the antiviral activities of various natural products isolated from plants against influenza viruses. Special focus is paid to the virucidal effects and the immune-enhancing effects of antiviral natural products, since the products have broad applications as inactivating agents for the preparation of inactivated vaccines and vaccine adjuvants.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.4
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• pp.86-90
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• 2023

The packaging of electronic devices performs a protective function to ensure that their durability and reliability are not affected by changes in the operating environment caused by external factors. Recent advances in materials have led to ongoing research into bonded packaging of heterogeneous materials such as polymers and inorganic materials in electronic devices. In this packaging process, it is important to have a binding that joins the materials and ensures the operating environment, which includes adhesion to the substrate, corrosion and oxidation resistance through moisture removal, and durability. In this study, the hygroscopicity of the coating layer by modifying the polymer surface based on PVA was evaluated by controlling and measuring the contact angle, and the adhesion was confirmed by applying water-based ink and testing according to ASTM_D3363. For the durability of the polymer surface, the IPL post-treatment process was used to improve the hardness and toughness against applied voltage, and the pencil hardness test and nanoindentation test were conducted. Through this, we analyzed and proposed solutions to ensure the reliability and durability of polymer devices in polymer microfabrication against environmental factors such as moisture, temperature fluctuations and adhesion, and surface abrasion.

• Journal of the Korean Institute of Gas
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• v.27 no.4
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• pp.43-49
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• 2023

Hydrofluoric acid is a less acidic substance than hydrochloric acid, nitric acid, and sulfuric acid, but it is one of the most dangerous substances for humans. In recent years, it has become an indispensable substance in industries such as chemical plants and the semiconductor industry, and although it is a threat to the human body, its use is increasing for various purposes, and the amount of use is constantly increasing due to the expansion and development of the industry. The dangers of hydrogen fluoride have been highlighted since the 2012 accident, which led to a more than fivefold increase in management standards for handling facilities. Hydrogen fluoride converts to hydrofluoric acid when exposed to the air, which can be fatal to humans. This study simulates the effects of a release of a toxic substance in the workplace, even though a protection layer has been provided to minimize the damage caused by the released toxic substance, and recommend ways to control the risk to workers in the event of a release in the workplace.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.8
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• pp.420-427
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• 2016

This study was conducted on the sediment remediation using micro-bubble to remove fine particles. For this study, characteristics of contamination and release in sediment were analyzed. And then, the characteristics of bubbles on removal efficiency was investigated at various operation conditions. In particle size distribution of the sediment used for the study, the proportion of clay and silt (<0.075 mm) was about 7.7%, sand (0.075~4.75 mm) was about 67.8%, and gravel (${\geq}4.75$) was 24.5%. Total nitrogen (TN) and total phosphorus (TP) of the sediment were 2,790~3,260, 261~311 mg/kg respectively. Ignition loss and water content were 4.1~9.6, 32.9~53.2% respectively. In analysis of removal efficiency according to operation conditions of micro-bubble, it was the highest when operation condition is pressure 6 atm, pressurized water ratio 30%, and coagulant dosage 15 ppm. At the time, the sediment's removal efficiency was 19.9%. Accordingly removal efficiency of TN and TP were 21.4, 22.6% respectively. Finally a research was found that fine particles in sediment were almost removed by micro-bubble, which led to decrease nutrients' release at about 20.1~64.3% in comparison to sediment including lots of fine particles.

• Cartoon and Animation Studies
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• s.46
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• pp.63-84
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• 2017

Overwhelming images of vividly colored aircraft flying across the blue sky and steam gushing from massive machines are reminiscent of Japanese animation films, especially of works by master director Hayao Miyazaki. By presenting together steam engines, which are mechanical devices of the Industrial Age in the past, and aircraft of the future age, the director constructs ambiguous space and time. These special time and space constitute nostalgia for past time, with devices called steam engines as a medium, and a longing for science and the future as represented by aircraft. In addition, the anticipation and disappointment, ideals and regrets of humans who see these two from the perspective of the present are projected on the works. This shares the characteristic of the steam punk genre, which seeks to return to the past rather than to face current problems. A subgenre of science fiction (henceforth "sci-fi"), steam punk reflects fundamental skepticism of science and technology and mechanized civilization, which have developed beyond human control. In addition, as works that clearly display such characteristics, director Miyazaki's and < $Nausica{\ddot{a}}$ of the Valley of Wind> can be examined. With spectacles of steam engines and aircraft, these two works enticingly visualize narratives about nature and humans and about the environment and destruction. Such attractiveness on the part of the master director's works has led to support from fans worldwide. However, often in the backgrounds of director Miyazaki's works, which have depicted ideal worlds of nature, environment, and community as highly concentrated fantasies, lie presuppositions of war and the end of the world. As works that are especially prominent in such characteristics, there are and . These two works betray the expectations of the audience by establishing the actual wartime as the temporal background and proceeding toward narratives of reality. Trapped in the ontological identity of the director himself, the war depicted by him projects a subjective and romantic attitude. Such a problem stems also from the ambiguity of the hybrid space and time, which is basic to the steam punk genre. This is because the basic characteristic of steam punk is to transplant past time, which humans were able to control, in the future from a perspective of optimism and longing via steam engines rather than to face current problems. In this respect, steam punk animation films in themselves can be seen as having significance and limitations at the same time.

• Journal of Life Science
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• v.33 no.12
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• pp.1015-1024
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• 2023

Antibiotics have greatly contributed to the treatment and prevention of bacterial diseases in humans, animals, and fish. However, antibiotic misuse has led to the emergence and spread of multidrug-resistant bacteria. In addition to antibiotic discovery research, efforts are being made to combat such multidrug-resistant bacteria using antimicrobial agents, antioxidants, host immune enhancement, probiotics, and bacteriophages, as well as various symptomatic therapies. To discover novel bioactive compounds, it is crucial to adopt approaches that incorporate fresh ideas, new targets, innovative techniques, and untapped resources. Halophytes are plants that grow in high-salt soils and are known to adapt to salt-induced stress through unique metabolic processes that produce secondary metabolites. This study aimed to investigate the effects of extracts of halophytes native to Korea on oxidative stress and to determine whether they exert inhibitory activity against biofilms, which are major pathogenic factors of infectious bacteria. The Acinetobacter baumannii strain ATCC 17978, a representative drug-resistant bacterium, was used to measure anti-biofilm activity. The results showed that Aster spathulifolius, Carex kobomugi, Rosa rugosa, and Asparagus cochinchiensis exerted strong antioxidant and anti-biofilm effects without affecting bacterial growth itself. The halophytes used in this study are promising candidates for the development of pharmaceutical agents with antioxidant and antimicrobial properties.

• Radiation Oncology Journal
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• v.28 no.4
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• pp.193-204
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• 2010

Purpose: To analyze the treatment outcomes, complications, prognostic factors after a long-term follow-up of patients with nasopharyngeal carcinoma treated with radiation therapy (RT) alone or concurrent chemoradiation therapy (CCRT). Materials and Methods: Between December 1981 and December 2006, 190 eligible patients with non-metastatic nasopharyngeal carcinoma were treated at our department with a curative intent. Of these patients, 103 were treated with RT alone and 87 patients received CCRT. The median age was 49 years (range, 8~78 years). The distributions of clinical stage according to the AJCC 6th edition included I: 7 (3.6%), IIA: 8 (4.2%), IIB: 33 (17.4%), III: 82 (43.2%), IVA: 31 (16.3%), IVB: 29 (15.3%). The accumulated radiation doses to the primary tumor ranged from 66.6~87.0 Gy (median, 72 Gy). Treatment outcomes and prognostic factors were retrospectively analyzed. Acute and late toxicities were assessed using the RTOG criteria. Results: A total of 96.8% (184/190) of patients completed the planned treatment. With a mean follow-up of 73 months (range, 2~278 months; median, 52 months), 93 (48.9%) patients had relapses that were local 44 (23.2%), nodal 13 (6.8%), or distant 49 (25.8%). The 5- and 10-year overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) rates were 55.6% and 44.5%, 54.8% and 51.3%, in addition to 65.3% and 57.4%, respectively. Multivariate analyses revealed that CCRT, age, gender, and stage were significant prognostic factors for OS. The CCRT and gender were independent prognostic factors for both DFS and DSS. There was no grade 4 or 5 acute toxicity, but grade 3 mucositis and hematologic toxicity were present in 42 patients (22.1%) and 18 patients (9.5%), respectively. During follow-up, grade 3 hearing loss in 9 patients and trismus in 6 patients were reported. Conclusion: The results of our study were in accordance with findings of previous studies and we confirmed that CCRT, low stage, female gender, and young age were related to improvement in OS. However, there are limitations in the locoregional control that can be achieved by CCRT with 20 conventional radiation therapy. This observation has led to further studies on clarifying the efficacy of concurrent chemotherapy by intensity modulated radiation therapy.