• Journal of the Korean Recycled Construction Resources Institute
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• 제11권2호
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• pp.120-129
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• 2023

Marine structures are subject to damage not only from sea salt but also from the adhesion of marine microorganisms and suspended particles, which cause additional damages. In order to prevent this, periodic coating is employed in the case of vessels to maintain the necessary performance. However, it is true that periodic coating is difficult for concrete or steel support structures, and there is a risk of marine environmental pollution. In this study, authors developed an anti-fouling coating agent using eco-friendly materials that possess hydrophilic cellulose nanofibers and AKD(alkyl ketene dimer). To achieve a homogeneous mixture, the content of cellulose nanofibers was fixed at 1 %, and AKD, distilled water, and waste glass were mixed using a digital mixer and homogenizer. The contact angle of the prepared coated surface was observed to be over 130°, indicating sufficient performance even in a water droplet flow test with a 15° slope, suggesting self-cleaning capability. Furthermore, through the analysis of viscosity characteristics at different temperatures, it was confirmed that the application is feasible at room temperature. Microstructure analysis also verified that the coating agent is uniformly applied to the concrete surface.

• Membrane Journal
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• 제34권1호
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• pp.38-49
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• 2024

Wastewater treatment using membrane bioreactors has been extensively used to alleviate water shortage and pollution by improving the quality of the treated water discharged into the environment. However, membrane biofouling persistently holds back an MBR process by reducing the process efficiency. Herein, we synthesized carbon nanospheres (CNSs) with many hydrophilic oxygen groups and utilized them as an additive to prepare high-performance ultrafiltration (UF) membranes with hydrophilicity and porous pore structure. CNSs were found to form crescent-shaped pores on the membrane surface, increasing the mean surface pore size by about 40% without causing significant defects larger than bubble points, as the CNS content increased by 4.6 wt%. In addition, the porous pore structure of CNS composite membranes was also attributable to the CNS's isotropic morphologies and relatively low particle number density because the aforementioned properties contributed to preventing the polymer solution viscosity from soaring with the loading of CNS. However, too porous structure compromised the mechanical properties, such that CNS2.3 was the best from a comprehensive consideration including the pore structure and mechanical properties. As a result, CNS2.3 showed not only 2 times higher water permeability than CNS0 but also 5 times longer operation duration until membrane cleaning was required.

• Korean Journal of Veterinary Service
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• 제20권1호
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• pp.1-9
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• 1997

The 37,000 holstein which had been raised in Jeju island were examined for the purpose of brucellosis detection and so on. We investigated the relationship between the farms showing positive outbreak and the number of examination, incubation period, and the outbreak rate of positive cattle. We endeavored to separate germs from brucellosis positive cattles blood and negative bulls semen against brucellosis serum test and concluded as follows. We intend to offer you institutional supplements and preventions of brucellosis for the future. 1. Outbreak of brucellosis could not lead the outbreak rate of positive cattle to decrease through 1-2 examination per year, For the past 4 years, the outbreak rate of brucellosis positive cattle had a tendency to show a gradual decrease through at least 5 examinations per year. 2. As we examined live-in cattle with positive cattle in mass outbreak farms for 9 months, we found out positive cattle every month. In a grazing land, the group of cattle producd enormous positive cattle in 9-12 months. 3. Annual brucellosis positive outbreak rate was 20-25% among live-in cattle with brucellosis positive cattle, but the rate might be 50-100% depending on extent of pollution. 4. 94's brucellosis examination showed that 200 positive cattle of 71,153 cattle and most of them were live-in cattle with confirmed brucellosis positive cattle. 5. 1 head of 200 positive cattle showed positivity against serum of bulls test and the rate of bulls was about 1%. 6. Brucellosis germ was separated from 2 cattle's semen among 52 negative bulls against brucellosis serum test and there was the one brucellosis positive cattle against tube agglutination of semen test, so the positive rate of brucellosis was 5.8%. 7. Brucellosis germ was not separated from 15 brucellosis positive cattle's blood.

• Herbal Formula Science
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• 제18권1호
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• pp.169-179
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• 2010

The pistil of nelumbo nucifera (PNN) is used in the treatment of nocturnal pollution, hematemesis, epistaxis, metrorrhagia and diarrhoea in traditional medicine. The present study was examined to evaluate the effects of PNN on the production of pro-inflammatory mediators in vitro. After the treatment of PNN, cell viability was measured by MTT assay, nitric oxide (NO) production was monitored by measuring the nitrite content in culture medium. The protein bands were determined by immunoblot analysis and levels of cytokines were analyzed by sandwich immunoassays. In the MTT assay, the doses of PNN extract (0.03, 0.10 mg/ml) had no significant cytotoxicity. The increases of NO production and inducible nitric oxide synthase expression were detected in lipopolysaccharide(LPS)-activated Raw 264.7 cells compared with control, in contrast, these increases were significantly attenuated by pre-treatment with PNN. In cytokine assay, the massive pro-inflammatory cytokines such as tumour necrosis factor-$\alpha$, interleukin (IL)-$1{\beta}$ and IL-6 were induced in LPS-activated Raw 264.7 cells, but pre-treatment of Raw 264.7 cells with PNN caused inhibition (TNF-$\alpha$=14.17%, IL-$1{\beta}$=107.43%, IL-6=46.27%) the production of cytokines by LPS. In addition, PNN reduced prostaglandin E2 productions in a dose-dependent manner (0.03mg/ml=37.52%, 0.10 mg/ml=83.77%) as a consequence of the inhibition of cyclooxygenase-2 expression. Taken together, our data indicates that PNN can regulate the inflammatory response in macrophage cells activated by Gram-negative infection.

• Hwankyungkyoyuk
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• 제18권2호
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• pp.113-125
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• 2005

Korea, China and Japan show distinct features in their school environmental education, which are derived from their own spreading processes. Japanese school environmental education has developed as a result of assimilating of anti-pollution education and nature education, and has a feature that makes much of nature experiences. The introduction of 'Period for Integrated Study' in 2002 seems to begin activating Japanese school environmental education. Chinese school environmental education started in higher education institutions around the middle of 1970's, and has a feature that makes a point of scientific approach, even in primary education schools. The two government ordinances,'National Action Program for Environmental General Knowledge ($1996{\sim}2010$)' and 'Educational Scheme of Environmental Theme Study for Elementary and Secondary School Students' issued in 2003, gradually promote school environmental education in China. It is remarkable that Science and Technology Centers for Youth and also increasing environmental NPOs often support environmental activities in elementary or secondary schools. The most notable feature of Korean school environmental education is that 'Environment' has already offered as a regular elective subject in junior high school, and official 'Environment' textbook has published since early 1990's. Though, the adoption rate of 'Environment' is not yet so high. Each country's peculiar issues are as follows. Japan: (1) Students often lack basic knowledge about environmental important problems. (2) 'Period for Integrated Study' is now threatened with cutting hours by the idea of increasing periods for basic subjects to keep high achievement. China: (1) There are large regional differences and school distinctions in operation of environmental education. (2) Adult environmental education needs to be expanded, because the most part of Chinese have no experience of school environmental education. Korea: (1) The relationship between the administrative division which plans school environmental education and teachers group is not quite well. The adoption rate of 'Environment' in junior high school needs to be improved. The training of many teachers for environmental education instructors may be the most important and effective cooperative action among Korea, China and Japan, and for that purpose we ought to work on making a better handbook for instructors, at first.

• Proceedings of the Korean Environmental Health Society Conference
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• 한국환경보건학회 2004년도 International Conference Current Challenges and Advances in Environmental Health
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• pp.63-68
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• 2004

Immunohistochemical and ultrastructural experiments were conducted to find out heavy metal accumulation in some selected organs such as the kidney, the digestive gland, and the gill of the Antarctic clam Laternula elliptica and R. philippinarum. According to the immunohistochemical study the subject organs of the clam showed reactions indicating the presence of MT (metallothionein), a metal-binding protein involved in metal detoxifying process. Examination under the transmission electron microscope also revealed that other ligands may play a role in metal accumulating and detoxifying process in L. elliptica and R. philippinarum. In the artificial exposure of the clam to Cd, the clams showed immediate subcellular responses. The level of the anti-MT reactions became higher in the proportion to the degree of pollution of their habitat and to the period of Cd exposure. These suggest that the two species can be used as efficient biomarkers for Cd exposure in the natural environment.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제47권6호
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• pp.874-881
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• 2014

A laboratory experiment was conducted to determine chronic effects of waterborne copper exposure on rock bream Oplegnathus fasciatus using a panel of enzymes. The activities of the following biochemical biomarkers were determined at different concentrations of $CuSO_4$ for 10 and 20 days: alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) in plasma; antioxidant enzymes including glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in liver and gills; and acethylcholinesterase (AChE) in brain and muscle. After exposure to two $CuSO_4$ concentrations (200 and $400{\mu}g/L$), the activities of plasma ALT in the fish showed a tendency to increase with AST and LDH, depending on $CuSO_4$ concentration. Additionally, GSH levels and SOD activities significantly increased, depending on $CuSO_4$ concentrations in liver and gills. This involved the inactivation of reactive molecules formed during oxidative stress, which could provide protection against oxidative damage induced by $CuSO_4$. However, GPx and AChE activities significantly decreased with $CuSO_4$ in liver and gills. In conclusion, these enzymes may represent convenient biomarkers for monitoring heavy metal pollution in coastal areas. Such chronic exposure studies are necessary for improving our understanding of complementary or deleterious effects of pollutants, and for developing metal toxicity biomarkers.

• The Journal of Fisheries Business Administration
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• 제29권1호
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• pp.27-63
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• 1998

This paper focuses on the history of fisheries finance in Korea, especially the role of fisheries finance after the establishments of korean fisheries cooperative. We can say that our fisheries was influenced greatly by the fisheries finance. It may be preyed by the facts that our fisheries experienced a great growth right after the input of big fisheries finance. The products of fisheries has increased from 1962 to now And the structure of the fisheries has improved. But there were unequal development in the each sectors of fisheries. Though the deep sea fishery and farming has developed faster, coastal fishing that are absorbing nearly 90% of fisheries population has stagnated. Of course it was because of unequal financial assistance by Authority. So to improve fisheries evenly, it is very important to overcome various problems that have encountered including the new circumstances like the WTO. For this, lots of steps should be taken. They can be summarized as follows. 1) It may be inevitable to see a rising costs in the deep sea fishery because of the declaration of EEZ by almost every nation. 2) So coastal fishing should be getting more important. It is necessary to improve the structure of coastal fishing and we should be ready to prepare various alternatives far self-sustained growth in coastal fishing. 3) Especially fisheries finance should play more active role. 4) Self-sustainable growth means a fishery with full compatability. For full compatability it is necessary to give financial supports far making fishing ground and equipping anti-pollution system and labour saving apparatus etc. 5) Also to raise the ratio of self-support in fisheries products it is necessary to give financial support to traditional financial system. 6) Moreover it is necessary to guide utilization of finance supplied. For this the committee that is consists of professional people in that field is strongly asked. This committee should be entitled to decide and coordinate the selection of projects, allocation of finance, method of utilization and evaluation of projects etc.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제30권3호
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• pp.329-343
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• 2004

Recently, our society has prominently raised the desire to well-being life since not only our economical situations are better than before, but environmental pollution become serious. In well-being trends, the natural or nature-related products are also issued on their usages as bio-/raw materials for our living industries, such as cosmetics, household goods, and so on. Especially, various materials which comes from medicinal plants has been discovered their physiological properties and validated their functions. Thus, they have been subjected to several processes, including extraction, isolation and concentration, and popularly introduced to cosmetic industry. In these reasons, a variety of cosmetic Products using natural materials has been developed, which are focused on whitening, wrinkle improvement, and anti-aging. In this report, we present a brief review of the function and classification of natural products interested in until now, and introduce the natural materials for cosmetics having physiological activities on skin, including Fructan, Acrea extract, Portulaca extract, Licorce extract, Dandelion extract, Ulmus extract, SC-glucan, Arbutin, and Sophora extract.

• Publications of The Korean Astronomical Society
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• 제30권2호
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• pp.255-259
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• 2015

Recent narrow-band Ca photometry discovered two distinct red giant branch (RGB) populations in some massive globular clusters (GCs) including M22, NGC 1851, and NGC 288. In order to investigate the differences in light/heavy elements abundances between the two subpopulations, we have performed low-resolution spectroscopy for stars on the two RGBs in these GCs. We find a significant difference (more than $4{\sigma}$) in calcium abundance from the spectroscopic HK' index for both M22 and NGC 1851. We also find a more than $8{\sigma}$ difference in CN band strength between the Ca-strong and Ca-weak subpopulations. For NGC 288, however, we detect the presence of a large difference only in the CN strength. The calcium abundances of the two subpopulations in this GC are identical within errors. We also find interesting differences in CN-CH relations among these GCs. While CN and CH indices are correlated in M22, they show an anti-correlation in NGC 288. However, NGC 1851 shows no difference in CH between two groups of stars having different CN strengths. The CN bimodality in these GCs could be explained by pollution from intermediate-mass asymptotic giant branch stars and/or fast-rotating massive stars. For the presence or absence of calcium bimodality and the differences in CN-CH relations, we suggest these would be best explained by how strongly type II supernovae enrichment has contributed to the chemical evolutions of these GCs.