• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.138-146
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• 1983

With the increase of pesticide consumption, not only pesticide handling population would grow greater but also the chances to be exposed to the pesticides would be also increased. Thus, safe use and handling of the pesticides are becoming more important and serious in these days. The pesticides are well known to most pepole, however there are very limited number of persons who have correct understanding of chamicals. Intoxication cases caused by pesticides have been reported very rarely through the mess media, even they were lack of scientific evidences. In this paper, problems related to pesticide manufacture, transportation, storage, sprays, and residues and their countermeasures were discussed in connection with public health and enviromental aspects. Acute intoxication cases by pesticide handling might be caused accidently either through manufacture, marketing, transportation, or spraying. Safety aspects of workers in manufacturing plants include not only exposure to toxic chemicals, but also posibilities of of explosion and brought about by pesticides and their diluents. The problems of water pollution by waste chemicals from the manufacturing factories were discussed. Packing and loading methods of pesticides for transportation are considered in safety scheme and discussions are given in association with traffic accidents. With regard to warehouse, the pesticide storage, location structure, keepers, and standing materials for emergency are concerned with safety aspects. Concerning the spraying of chemicals, there are some problems to be discussed about clothes, spray equipment, wind direction, spray period, and spray workers condition. After the spray, treatment of used containers, remainder of Pesticides, and spray tools are also discussed. For the dissolutions of problems on public health and environmental danger arising from pesticide residues, there are two legal sanctions; 'Pesticide Tolerances' and 'Pesticide Safe Use Standards'. These regulations are legally effective, however, some problems still remain in practices to implement the acts properly, because these provisions are followed by the far mers mostly. With these regards, most problems are concerned with various sectors and persons, affecting public health and environment from the producers to the end users and consumers. As a whole persons concerned with pesticides, every possible effort has to be assembled to protect hazards from the chemicals. For the foremost place, special training and education are required for managing groups; such as factory managers and agricultural extension workers who are responsible for training the factory workers and farmers. The education is the only way to solve the hazard problems caused by the pesticides.

• Journal of Korean Academy of Nursing
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• v.25 no.1
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• pp.99-109
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• 1995

Post-operative wound infections have been the serious problems in nursing care in the operating room and appear to be strongly related to the infection occurring during the operation. The purpose of this study is to identify the level of contamination in saline used in the operation and also examine the correlation between the contaminated saline and the length of the operation, and unclean atmospheric factor. Subjects for this study include 13 cases of operation performed at the operative theatre of a hospital in Seoul area. Test samples and related data were collected from this medical facility between Oct. 6 through Dec. 10, 1994 by the author and anurse who worked in the operating room. For the study, multiple batches of saline sample were collected at the various time intervals duringthe operation and filtered through the membrane filters. Viable microorganisms retained on the filters were cultured on the appropriate culture media and the levels of existing cells in saline were enumerated according to Koch's method. In the analyses of the data, Pearson's correlation coefficient was obtained for the examination of relationship between the length of operation and numbers of microorganisms existing in saline and for the comparison of the differences in numbers if microrganisms in saline sample collected at the various operative stages, e. g. pre-incision, excision and skin suturing stages, ANOVA and Scheff Tests were performed. The results of this study are summarized as follows. 1) The lenth of the operation and numbers of microorganisms in the saline used in the operation appeared to be significantly correlated (r=0.5467, P<0,001). 2) In case of saline exposed to air, but not used in the operation, the length of exposure to the air and the numbers of microorganisms present in saline also showed an apparent correlation(r=0.5087, P<0. 001). 3) The frequencies of occurrence of microorganisms in saline used in the operation and in saline exposed only to the air in the given time showed significant differences(t=3.73, p=.0000). 4) In case of saline used in the operation, there is significant differences in its numbers of contained microorganisms between the operative stages ; pre-incision, excision, and skin suture (F=17.7500, p=.0000). 5) In case of saline exposed only to the air in the given time, there is significant differences in its numbers of contained microorganisms between the operative stages . pre-incision, excision, and skin suture(F=6.3807, p=.00031).

• Journal of Korean society of Dental Hygiene
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• v.10 no.2
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• pp.255-268
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• 2010

Objectives : In the field of dental hygiene, infections pose a serious problem. This issue has left many patients and dental staff exposed to microbes with potentially far-reaching effects. The purpose of this study was to find solutions which could improve Dental health policies and promote improved methods for the control of infections. This survey was conducted between March 3, 2008 and March 30, 2008, in the metropolitan area. The research was carried out in dental clinics and dental hygienists were surveyed through a questionnaire. Methods : Collected data was examined using the SPSS 14.0 program, using frequency, mean and standard deviation analysis, T-test, one-way ANOVA, Scheffe's test and Duncan's test. Further analysis was given using Logistic Regression. Results : The Performance of Infection Control by dental hygienists in Dental Clinics was shown at $2.96{\pm}0.42$. Disinfection, sterilization and the wearing of masks is high at $3.65{\pm}0.64$, $3.64{\pm}0.65$. The perception of the importance of infection control is higher among dental hygienists than dentists. Of the dental hygienists surveyed, 83.9% were exposed to at least one accident while at work. Age and years of experience were important in relation to infection control practices. The rate of infections and the number of accidents experienced related to the dental hygienists performance of infection control. The performance of infection control is influenced by the dental hygienists own perceptions, and the perceptions of their dentists. The dental hygienist's working conditions and their beliefs related to infection control were shown to influence their performance of infection control practices. Conclusion : At the conclusion of this investigation, it was determined that systematic refresher training of infection control should be delivered through further education and various media. Dental health care workers should be encouraged to practice these action items presented in the training. For successful implementation of infection control in every dental health-care setting, it is highly demanded that effective safe-guard tools, strategic support and standardized action items against infection problems are developed.

• Journal of Conservation Science
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• v.33 no.6
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• pp.467-483
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• 2017

In this study, the degradation properties by temperature stress of $Araldite^{(R)}$ rapid-curing epoxy resin used for inorganic cultural heritages, was identified. The tensile and tensile shear strength of durability decreased for 12,624 hours at temperatures of $40{\sim}60^{\circ}C$. In terms of stability of external stress and temperature, the slow-curing epoxy was superior to the rapid-curing epoxy, and cultural heritage conservation plans should therefore consider the strength and stress properties of restoration materials. Color differences increased for 12,624 hours at temperatures of $40{\sim}60^{\circ}C$, and glossiness decreased. Both color and gloss stability were weak, which necessitates the improvement of optical properties. Thermal properties (weight loss, decomposition temperature, and glass transition temperature) of adhesives are linked to mechanical properties. Interfacial properties of the adherend and water vapor transmission rates of adhesives are linked to performance variation. For porous media (ceramics, brick, and stone), isothermal and isohumid environments are important. For outdoor artifacts on display in museums, changes in physical properties by exposure to varying environmental conditions need to be minimized. These results can be used as baseline data in the study of the degradation velocity and lifetime prediction of rapid-curing epoxy resin for the restoration of cultural heritages.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.221-225
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• 2011

This study was undertaken to evaluate the relationship between in vitro maturation and plasminogen activators (PAs) activity on porcine cumulus-oocytes complexes (COCs) exposed to oxidative stress. When COCs were cultured in maturation medium with hydrogen peroxide ($H_2O_2$), the proportion of the germinal vesicle breakdown (GVBD) and oocytes maturation were decrease with addition of $H_2O_2$, and were significantly (p<0.05) lower in medium with 0.1 mM $H_2O_2$ than control group. Also, the rate of degenerated oocytes was increased in as $H_2O_2$ concentration in eased. When COCs were cultured for 48 h, three plasminogen-dependent lytic bands were observed: tissue-type PA (tPA); urokinase-type PA (uPA); and tPA-PA inhibitor (tPA-PAI). PA activity was quantified using SDS-PAGE and zymography. When $H_2O_2$ concentration was increased, tPA and tPA-PAI activities also increased in porcine oocytes cultured for 48 h, but not uPA. In other experiment, embryos were divided into three groups and cultured in (1) control medium, (2) control medium with 1.0 mM $H_2O_2$ and (3) control medium with 1.0 mM $H_2O_2$ along with catalase in concentrations of 0.01, 0.1, and 1.0 mg/ml, respectively. $H_2O_2$ decreased the rate of GVBD and maturation in porcine COCs but catalase revealed protective activity, against oxidative stress caused by $H_2O_2$. In this experiment, tPA and tPA-PAI activities were higher in media with 1.0 mM $H_2O_2$ alone. Increasing concentration of catalase decreased tPA and tPA-PAI activities in porcine oocytes. These results indicate that the exposure of porcine follicular oocytes to ROS inhibits oocytes maturation to metaphase-II stage and increase the oocytes degeneration. Also, we speculated that increased ROS level may trigger tPA and tPA-PAI activities in porcine oocytes matured in vitro.

• Science of Emotion and Sensibility
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• v.22 no.3
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• pp.103-108
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• 2019

Although the Korean Armistice Agreement resulted in complete cessation of the hostilities of the Korean War, it also initiated a rule that obligates Korean men to compulsorily participate in military service. However, psychological factors such as anxiety, stress, and negative perception among the young participants joining the military lead to inefficiency in training and performance. Several types of media production companies have been tasked to deal with this problem. However, their tools have not adequately addressed the root causes of the psychological distress. Stress rates are still high among the youth. This paper offers a method of reducing anxiety and psychological stress among those joining the military. It also aims to help improve concentration and cope with the pessimism of military life. The study measured the increase in concentration as well as the changing rate of anxiety and psychological stress in the participants of two experimental groups. A significant result with t = 2.487, p = 0.042, and 95% confidence levels was revealed by analyzing the data pertaining to the experimental group that was directly exposed to the sensorimotor rhythm (SMR) wave implying that this brain wave alleviated feelings of anxiety and psychological stress. The method proposed in this paper can thus be applied to mitigate stress in soldiers and help them with their personal and military lives. Further interdisciplinary experiments examining the associations between the electrocardiogram and electroencephalogram are required.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.808-817
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• 2011

Because of its elevated cellulolytic activity, the filamentous fungus Trichoderma harzianum has a considerable potential in biomass hydrolysis applications. Trichoderma harzianum cellobiohydrolase I (ThCBHI), an exoglucanase, is an important enzyme in the process of cellulose degradation. Here, we report an easy single-step ion-exchange chromatographic method for purification of ThCBHI and its initial biophysical and biochemical characterization. The ThCBHI produced by induction with microcrystalline cellulose under submerged fermentation was purified on DEAE-Sephadex A-50 media and its identity was confirmed by mass spectrometry. The ThCBHI biochemical characterization showed that the protein has a molecular mass of 66 kDa and pI of 5.23. As confirmed by smallangle X-ray scattering (SAXS), both full-length ThCBHI and its catalytic core domain (CCD) obtained by digestion with papain are monomeric in solution. Secondary structure analysis of ThCBHI by circular dichroism revealed ${\alpha}$- helices and ${\beta}$-strands contents in the 28% and 38% range, respectively. The intrinsic fluorescence emission maximum of 337 nm was accounted for as different degrees of exposure of ThCBHI tryptophan residues to water. Moreover, ThCBHI displayed maximum activity at pH 5.0 and temperature of $50^{\circ}C$ with specific activities against Avicel and p-nitrophenyl-${\beta}$-D-cellobioside of 1.25 U/mg and 1.53 U/mg, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.2
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• pp.79-86
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• 2007

The aim of the present study was to determine mechanisms of corneal epithelial cell apoptosis in vitro following exposure to anti-FAS and anti-FAS ligand antibody and during infection with mycoplasma sp.. A cultured human corneal epithelial(HCE) cell line was treated with anti-FAS antibody or anti-FAS ligand antibody for 2 and 4 days. The original cell line was found to be contaminated by mycoplasma removal agent(MRA) was used to eliminate the bacterium from the cell line. MRA($0.5{\mu}{\ell}$ tissue culture medium) was added to the cell line and incubated for 1 week. The cell line underwent multiple passages in media not contaminating MRA and cells were grown to 50-80% confluency on coverslips and stained using the Hoechst stain provided in the kit to ensure mycoplasma removal. Apoptosis experiments were performed before and after mycoplasma removal. The apoptotic index of anti-FAS and anti-FAS ligand antibody on mycoplasma contaminated cell line was studied using Hoechst 33342 staining and Annexin V-FITC and Propidium Iodide Staining. In conclusion, anti-FAS antibody induces apoptosis in HCE cells in a time and concentration-dependent mechanism. Cell lines contaminated with mycoplasma have an incresed susceptibility to FAS induced apoptosis.

• Journal of Wetlands Research
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• v.9 no.1
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• pp.79-89
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• 2007

This paper provides a comprehensive overview of the present status of several environmental problems caused by emerging toxic substances such as persistent organic pollutants (POPs), endocrine disrupting chemicals (EDCs), and arsenic in various environmental media in Vietnam. Monitoring data reported during the 1990s demonstrated elevated contamination of DDTs in most of these compartments in Vietnam. Studies in frame of the Asia-Pacific Mussel Watch Program revealed that fish, mussels and resident birds from Vietnam contained higher concentrations of DDTs as compared to other countries in region, suggesting the role of Vietnamese environment as a significant emission source of DDT in the Southeast Asian region. The estimated dietary intakes of PCBs and DDTs for Vietnamese were relatively high among Asian developing countries, suggesting potential risk for humans posed by thesechemicals. Widespread contamination of some endocrine active compounds such as alkylphenols and phthalates was observed at various sites along the coasts of northern and middle Vietnam. The presence of significant source of bisphenol-A along Red River estuary was revealed with the concentrations comparable to those reported for developed nations. A case study on seasonal variation of alkylphenols and phthalates in surface water of river delta and estuary of north and middle Vietnam indicated the differences in distribution of these compounds between dry and rainy seasons. Higher concentrations of alkylphenols and phthalates were found in dry season in estuary; while the contrasting pattern was observed in the river delta, showing elevated residues in rainy season. This result suggests the different behavior of alkylphenols and phthalates in river delta and coastal environment. From ecotoxicological perspectives, concentrations of bis-phenol A and di(2-ethylhexyl)phthalates [DEHP] in surface water from some locations in Vietnam exceeded the guideline values for Ecotoxicological Effects and the Environmental Risk Limit, respectively, suggesting potential for toxic implications on aquatic wildlife. Widespread and elevated arsenic contamination was discovered inour recent surveys in groundwater in a large area of suburban areas of Hanoi city, the capital of Vietnam. The most recent investigation in 4 villages showed about more than 50 % of groundwater samples contained As concentrations exceeding 50 g/L (the WHO and Vietnamese standard). In particular, in Son Dong villages, 58 % of samples analyzed contained As concentrations higher than 200 g/L. Good correlations were found in As concentrations in water and hair and urine of peoples in corresponding families, suggesting the chronic exposure to As by people living in As-contaminated ground water areas. In Son Dong village, As levels in hair (mean: 1.7 mg/kg dry wt) and urine (g/g creatinine) exceeding the reference values recommended by WHO, suggesting potential for human risk posed by long term accumulation of As in human body. Future studies should be focused on the time trends of POPs and EDCs in biota in Vietnam in order to predict future trend of contamination and to reveal new clues for understanding possible toxic impacts on aquatic organisms. The issues of arsenic contamination in groundwater and their chronic toxic implications on human health should be systematically investigated in the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.143-150
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• 2018

With the rapid development of RF based high speed wireless communication technology, devices that can be applied to IoT networks based on RF bandwidth are rapidly spreading, nevertheless, the development speed of the RF communication is not possible to keep up with the spread of the RF band for wireless communication. In this situation, OWC technology that uses visible light source as a transmitter is attracting attention as a technology that can overcome the band exhaustion problem of RF based wireless communication technology. Although, due to the distortion of the LED illumination shape by camera exposure time and LED blinking period, the LED illumination detection rate is degraded and the RoI setting is inaccurate. In this paper, we propose an adaptive median filter applied LED illumination detection algorithm for low rate CamCom, it is possible to detect a clear RoI and LED illumination. This research will be able to play a role as a complementary material of RF based wireless communication technology efficiently.