• ALGAE
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• 제29권4호
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• pp.311-319
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• 2014

The biocide sodium hypochlorite (NaOCl) is widely used for controlling algal growth, and this application can be extended to marine environments as well. This study evaluates the biocidal efficiency and cellular toxicity of NaOCl on the harmful dinoflagellate Cochlodinium polykrikoides, with emphasis on pigment production and antioxidant enzyme activity. The test organism showed dose-dependent decrease in growth rate on exposure to NaOCl, and the 72 h $EC_{50}$ was measured to be $0.584mg\;L^{-1}$. NaOCl significantly decreased pigment levels and chlorophyll autofluorescence intensity, indicating possible detrimental effects on the photosystem of C. polykrikoides. Moreover, it significantly increased the activities of antioxidant enzymes, suggesting the production of reactive oxygen species in the cells. These data indicate that NaOCl exerted deleterious effects on the photosynthetic machinery and induced oxidative damage in the dinoflagellate and this biocide could be effectively used for the control of algal blooms.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 1998년도 추계학술발표회
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• pp.41-57
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• 1998

Five hundreds of bifidobacteria were isolated from an healthy Korean and the inhibitory effects of these isolated bacteria on harmful enzymes of human intestinal microflora were examined by cocultivation of the isolated bifidobacteria with E. coli HGU-3 or total human intestinal microflora. In comparison with the results of E. coli or intestinal microflora cultivation, Bifidobacterium breave K-110, B. breve K-111 and B. infantis K-525 effectively inhibited harmful enzymes (${\beta}-glucuronidase$ and tryptophanase) of E. coli and lowered the pH of the culture media. Also they inhibited the harmful enzymes (${\beta}-glucosidase$, ${\beta}-glucuronidase$, tryptophanase and urease) and ammonia production of intestinal microflora, and lowered pH of the culture media by increasing the number of bifidobateria on intestinal microflora. The inhibitory effect of bifidobacteria on Growth of Helicobacter pylori and Rotavirus infection were exammed. Bifidobacterium K-110 and K-111 inhibited effectively them. When these isolated bifidobacteria were administered to mice, the activities of fecal harmful enzymes were inhibited and the AC and ACF formation were suppressed. Among tested bifidobacteria, B. breve K-110 had high inhibitory effect of fecal harmful enzymes and ACF formation.

• 한국식품영양학회지
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• 제28권3호
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• pp.486-492
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• 2015

This study was conducted to provide fundamental data on the awareness of radiation, specifically the differences between general awareness, psychological state and harmful effects. Data was collected from 334 University students in the Chungbuk region through a self-administered questionnaire. According to the results of the reliability and factor analysis, the awareness of radiation was 2.80, with a Cronbach alpha coefficient of 0.815 and KMO of 0.798. Factor analysis extracted three components of the awareness of radiation, which we named general awareness (factor 1), psychological state (factor 2), and harmful effect (factor 3). There were significant differences in the general awareness of natural radiation and radiation-containing foods (p<0.05), whereas no significant differences were found in the general awareness of radiation food supply (p>0.05). Also, the psychological state showed a significant difference in exposure inspection, future exposure, and radiation-containing food (p<0.05), whereas no significant differences were found in the refusal of radiation inspection (p>0.05). The harmful effects showed a significant difference in the rejection of radiation (p<0.05), but no significant differences in the cancer and genetic effects, diseases and physical harmfulness (p>0.05). A significant positive result (p<0.05) was found for the psychological state according to the harmful effects of radiation. Based on this study, detailed and continuous education must be accomplished by increasing the awareness of radiation and the acceptance level, conveying a proper understanding of radiation and assisting subjects with receiving the information they desire through various educational mediums.

• Journal of Radiation Protection and Research
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• 제34권3호
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• pp.95-101
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• 2009

Protective behavior of radiological technologists against radiation exposure is important to achieve reduction of the patient doses without compromising medical achievements. This study attempts to provide a basic model for the sophisticated intervention strategy that increases the level of the protective behavior of the technologists. The model was applied to real situations in Korea to demonstrate its utility. The results of this study are summarized as follows: First, the protective environment showed the highest relationship in the factors considered, r=0.637 (p<0.01). Secondly, the important factors were protective environment in environment characteristics, expectation for the protective behavior 0.228 (p<0.001), self-efficacy 0.142 (p<0.001), and attitude for the protective behavior 0.178 (p<0.001) in personal characteristics, and daily patient -0.112 (p<0.001) and number of the participation in the education session for the protective behavior 0.074 (p<0.05). Thirdly, the final protective behavior model by a path analysis method had direct influence on the attitude 0.171 (p<0.01) and environment 0.405 (p<0.01) for the protective behavior, self efficacy 0.122 (p<0.01), expectation for the protective behavior 0.16 (p<0.01), and self-efficacy in the specialty of projects 0.154 (p<0.01). The acceptance of the model determined by the absolute fit index (GFI), 0.969, and by the incremental fit index (CFI), 0.943, showed very significant levels. Value of $x^2$/df that is a factor applied to verify the acceptance of the model was 37, which implies that the result can be accepted in the desirable range. In addition, the parsimonious fit index configured by AGFI (0.890) and TLI (0.852) was also considered as a scale that accepts the model in practical applications. In case of the establishment of some specific intervention strategies based on the protective behavior model against harmful radiation effects proposed in this study, the strategy will provide an effective way to prevent medical harmful radiation effects that could cause severe injuries to people.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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• pp.502-506
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• 2008

Smoke composed of harmful gases such as carbon monocide and carbon dioxide is reconized as the major killer in fire situation. Especailly it is said that smoke movement is related to the panic phenomenon which threatens the life seriously. The purpose of this study is to investgate and analyse the reaction mechanism of harmful gas caused by fire effects on the human psychology and panic phenomenon.

• 정보교육학회논문지
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• 제11권3호
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• pp.329-337
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• 2007

IT 분야의 급속한 성장은 편리성과 더불어 역기능과 유해정보를 초래했으며, 이로 인해 많은 청소년들이 정신적, 인성적 발달에 심각한 장애를 받고 있다. 본 연구는 유해정보에 대한 초등학생들의 실태를 분석하고, 초등학생들을 보호하기 위한 다양한 교육적 방안을 마련하는데 목적이 있다. 이를 위해 각종 문헌과 사전 연구물을 통해 유해정보의 현황을 분석하고 유해정보의 정의와 유형을 제시하였다. 또한 다양한 유해정보 실태 보고서를 비교분석하여 초등학생의 유해정보 실태를 분석하였으며, 이를 통해 학생, 교사, 학부모에 대한 교육적 보호 방안을 제시하였다. 본 연구에서 제안한 교육적 방안은 정보통신윤리 교육과정 구성과 교사, 학부모 교육 등에 활용될 수 있을 것이다.

• 한국물환경학회지
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• 제39권3호
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• pp.223-230
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• 2023

Harmful algae blooms have become a serious environmental problem in major river basins in Korea. They are known to produce various algal organic matters (AOMs) including intracellular organic matters (IOMs) and extracellular organic matters (EOMs). Generally AOMs cannot be easily removed by coagulation/flocculation process in conventional drinking water plants. AOMs produced by blue-green algae also include various toxins such as Microcystins, Anatoxin-a, and Saxitoxin known to have harmful effects on living organisms in aquatic environment. In this study, toxic effects of EOMs produced by three different algae species (Microcystis sp., Anabaena sp., and Oscillatoria sp.) on zebrafish were investigated using electroencephalography (EEG) recording method, a technology for recording brain activity. Electroencephalographic changes in zebrafish revealed that a low EOM had a negative effect on zebrafish compared to both Anabaena sp. and Oscillatoria sp. at 30 ppm EOM exposures. This result might be due to Microcystins present in EOMs produced by Microcystis sp. As a result of power spectrum density anallysis, exposure to EOMs produced by Microcystis sp. caused a state of vigilance in zebrafish. This EEG based toxicity test can be used to examine effects of harmful materials at low levels on living organisms in an aquatic system.

• 아동학회지
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• 제27권2호
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• pp.153-165
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• 2006

This study examined moderating effects of mother's support and community environment on relationships between after school self-care and problem behaviors. Subjects were 579 3rd and 6th grade elementary school children. Major findings were positive relationships between after school self-care and problem behaviors. Neither gender differences nor grade differences were found in the relationships between after school self-care and problem behaviors. Moderating effects of care by relatives or neighbors on mother's support was shown in the relationships between after school self-care and internal problem behaviors. Moderating effects of proximity to harmful facilities were found in relationships between after school self-care and external problem behaviors.

• The Journal of Korean Physical Therapy
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• 제13권1호
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• pp.139-149
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• 2001

We found out that there exists threshold dose for the decreased platelet count when we apply change of the platelet count to the defense of the ultrasound experiment. Those diminution is definite effects from the defense of the ultrasound. The number of the platelet count is decreased when we are exposed to ultrasound simultaneously. This should not be occurred. It is easy to use the number of the platelet count in the measurement of the biological dosage and intensity in high dosage relatively due to definite quantative relationship. The biological index to understand synergic effects. which are present when two harmful environmental factors are operating at the same time is functionally assending and antagonistic. There are scattered many factors as physical, Chemical, or physiochemically elements which are harmful to human body in the environment in consideration of ultrasound and the other factors. This experiment is demonstrating that we can use the change of the platelet as an index representing synergic effects of ultrasound.

• 한국보건간호학회지
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• 제14권2호
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• pp.229-245
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• 2000

Previous studies have shown that five representative behaviors affect the health of adults in everyday life : smoking, drinking, exercise, nutrition, and stress. This study focuses on these five behaviors in an attempt not only to develop a program that promotes health, but also to suggest ways that such a program may be implemented to reflect diverse lifestyles. Our aim is to show how individual subjectivity influences behavior when making lifestyle choices that affect health. By analyzing individual characteristics, we tried to group people according to their common attitude and behaviors to promote health. We hope that this study may provide the fundamental data which may be used to assist professionals in promoting healthy behaviors among adults. In order to examine how subjectivity(e.g, personal opinions or attitudes) influences behavior, we prepared Q-statements which were composed of Q-samples for the study of human subjectivity. We polled forty-two adults and then analyzed the results using a PC qunal program. As a result, the respondents were classed according to six different types. Type One includes people who think managing stress is the most effective way to live a healthy life. They regard smoking and drinking as harmful behaviors. Type Two subjects, on the other hand, regard smoking and drinking as a matter of taste with few harmful effects. Although they recognize the importance of managing stress, they have a positive attitude towards smoking and regard nutrition as a minor factor in promoting their healthy lifestyle. Those classed as Type Three emphasize the necessity of exercise. They perceive drinking, smoking, and stress as harmful. People in this category seek to increase physical strength and to regulate all five health behaviors by keeping them in a normal range. Type Four consists of people who are indifferent to their health. While they seem to recognize the importance of regular exercise, they pay little attention to nutrition or to the harmful effects of smoking, drinking, and stress. They believe that exercise alone is sufficient to maintain their health. Type Five subjects believe drinking is not a harmful behavior at all. Rather. it has a positive effect on their mental health. They are characterized by this positive attitude towards drinking as well as by indifference toward nutrition (although they readily admit that good nutrition is important). Finally. those classed as Type Six have a positive attitude toward moderate drinking as a means to relieve stress. However. they also recognize the harmful effects of excessive drinking. They regard good nutrition as an important lifestyle choice but are indifferent toward exercise. This type is engaged in passive health management. This study devised six types or categories that reflect different attitudes toward promoting health in everyday life. It further went on to analyze the characteristics of each type. This study shows that programs designed to promote health must be modified to reflect the diversity of individual attitudes and patterns of behaviors.