• Journal of Ginseng Research
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• v.28 no.3
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• pp.149-156
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• 2004

The objectives of this study were to investigate the morphology of mycorrhizal roots, and the effects of root age and soil texture on the mycorrhizal infection in ginseng (Panax ginseng C. A. Meyer) growing in Korea. Ginseng roots at ages of two to six years were collected from fields in late June. Their infection by arbuscular mycorrhizal fungi(AMF) was studied by clearing the roots and staining fungal hyphae with trypan blue. Root infection varied greatly depending on the developmental stages of young roots. Young tertiary roots, in diameter of smaller than 0.8 mrn, formed during the current growing season had root hairs and were frequently and in some cases heavily infected by AMF. Hyphal coils and arbuscules were abundant, while vesicles were rarely observed. Older secondary or tertiary roots in diameter of bigger than 1.0 mm with fully differentiated primary xylem formed during the previous growing season had no root hairs, and were not infected at all. The rates of mycorrhizal infection in the young tertiary roots were not affected by the age of the ginseng plants, suggesting that fungal populations might have not much changed during the aging of the cultivated fields up to six years. The differences in the infection rates among the different ages of ginseng were caused by differences in the amount of young tertiary roots in the samples. Soil texture, either sandy loam or clay loam, did not affect the rate of root infection. There were large variations in the infection rates among the different farms and locations within a farm. It strongly suggested that infection rates of the ginseng roots by AMF would be influenced by the practice of the farmers, possibly by avoiding consecutive planting, introduction of new topsoil, and the ways of handling the soil before transplanting the ginseng, such as fumigation or sterilization that might have affected indigenous inoculum sources of the AMF.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.633-642
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• 2010

In this study, science teachers' perception and attitude toward nanotechnology are examined through questionnaires gathered from 134 secondary science teachers. As a result, the study shows that science teachers have high perceptiveness. However, they do not understand specific information on nanotechnology correctly. Science teachers have positive attitudes toward nanotechnology and they have perceived risks of nanotechnology as well as benefits of nanotechnology. Science teachers show positive attitudes toward the application of nanotechnology, whereas they show negative attitudes toward personal information chip and nano-taste enhancer. Science teachers are exposed to nanotechnology via various sources such as TV and internet, whereas teachers rarely get information on nanotechnology-related concepts in textbooks and teaching resources. Science teachers have perceived many textbooks do not introduce enough nanotechnology-related concepts. Many teachers try to explain the nanotechnology when textbooks include nanotechnology-related concepts, whereas quite a few of teachers do not introduce the nanotechnology-related concepts in class.

• Journal of the Korean Geophysical Society
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• v.2 no.4
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• pp.241-250
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• 1999

Reflection coefficients of the seafloor have been calculated from the amplitude ratio of secondary to primary water bottom reflection in seismic data obtained from Bransfield Strait, Antarctic Peninsula. Test processing for the coefficients shows that moving average is effective to reduce severe fluctuation of the coefficient measured at each point. Relationship between the coefficients and the properties of water bottom is analyzed to illuminate geological environment. In the central Bransfield Basin, the magnitude of reflection coefficients decreases as it is distant from the sedimentary sources. Reflection coefficients range from 0.12 to 0.2 near the continental slope of the basin, and from 0.1 to 0.12 in the basin floor. In the western Bransfield basin, reflection coefficients between 0.2 to 0.3 are obtained from the area eroded by glacial movement. On the volcanic structures near Deception Island, the coefficients show relatively high values more than 0.2. Paleo-geological structures uplifted by tectonic movement and outcropped by glacial erosion have relatively high coefficients.

• Journal of Korean Academy of Rural Health Nursing
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• v.4 no.1
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• pp.31-40
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• 2009

Purpose: This research was done do identify and analyze the beginnings of the community health practitioner system in the Republic of Korea (ROK) around 1980. Method: Primary sources were collected and analyzed, mainly newspapers around 1980, the act for health service for rural areas, and other relative publications. Results: The government of the ROK was trying to solve the problem of doctorless villages and regarded the introduction of primary health care (PHC) services using registered nurses (RNs) to be an economic solution to this problem. The Korean Nurses' Association presented 'a plan for community health service' to the government party and medical association in 1976. In this plan, RNs would provide primary care at the sub-county (myun) level, and hospital would provide secondary care. The Korean Public Health Development Research Center was awarded the project 'RNs and nurse aids as CHP for primary care service and their training'. In 1977, 25 RNs began to work as PHC in 3 areas, and interim findings showed that RNs were very capable of doing PHC. The Ministry of Health and Welfare announced long term plans for health and welfare administration including a tertiary health care delivery system. RNs after training were posted to rural areas with no medical services to do medical treatment for mild cases. The Act for health services for rural areas was enacted on December 31, 1980. Enforcement Ordinance and Enforcement Regulations were enacted in 1981. In 1981, 257 CHP were selected, trained, and deployed. In 1983, the president of the ROK announced continuation of the CHP system for residents of medically vulnerable areas. The number of CHP increased from 257 in 1981 to 2038 in 1989.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.242-245
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• 2003

Buckwheat contains dietary rutin, a flavonol glycoside, which is able to antagonize hypertension in human and has antioxidant activity. Monacolin K, a secondary metabolite produced by fungi Monascus species, is an effective specific inhibitor of cholesterol biosynthesis. To develop functional health food, dehulled buckwheat was fermented with Manascus ruber to produce Anka, and contents of rutin and monacolin K and Anka were determined. The rutin content in dehulled buckwheat decreased slightly after germination, but increased with the growth of sprout. Growth of fungi had no influence on rutin content in dehulled buckwheat Anka, Monacolin K content in fermented dehulled buckwheat malt was lower than that in dehulled buckwheat Anka. Monacolin K content in dehulled buckwheat Anka decreased with increasing length of sprout in fermented dehulled buckwheat malt, probably due to consumption of nutrients, such as polysaccharides as carbon sources, during sprouting for growth of M. ruber.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.4
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• pp.181-201
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• 2017

Even though the increasing number of researches of school libraries have grown for the last 36 years, the diverse and practical problems of school libraries and teaching librarians have not been addressed to the proper solutions. This article presents an overview of the characteristics and tendency of researches using the method of systematical review in order to check the assumptions and research consequences of school libraries and teaching librarians. Results show that survey study reviewing or comparing certain cases is the most common types of research methods, and that the majority of studies that relied only on prior studies or secondary data from other sources to make their claims and rarely specify the five criteria validating study process and methodological reliability. Some research questions for future study including necessity of change in problem-solving perspective are provided.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.727-736
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• 2016

The ambient mass concentration and chemical composition of the $PM_{2.5}$ were determined at the highland site with 1,100 m above sea level on Jeju Island from June 2013 to November 2014. Yearly averaged mass concentration of $PM_{2.5}$ was $11.97{\pm}8.63{\mu}g/m^3$. $PM_{2.5}$ concentrations were highest during the spring, while they tended to be lowest during the summer. Eight water soluble ionic species attributed 45.5% to $PM_{2.5}$ mass. $SO{_4}^{2-}$, $NO_3{^-}$ and $NH_4{^+}$ were major ions, which occupied to 27.9%, 3.7% and 12.3%, respectively. The greatest contributors to total mass concentration of water-soluble ions contained in $PM_{2.5}$ were sulfate, ammonium and nitrate. These three ions accounted for 96.6% in total ions mass concentration of $PM_{2.5}$. We could infer that these three secondary ions exist mostly in the form of $(NH_4)_2SO_4$ and $NH_4NO_3$. $Ca^{2+}$ and $Mg^{2+}$ had a good relationship and with r=0.9. The molar ratio of $Mg^{2+}/Ca^{2+}$ in this study was lower than the value observed in sea water and higher than that in soil dust, indicating that these two ions originated from other sources rather than ocean and soil dust in this study.

• Safety and Health at Work
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• v.9 no.3
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• pp.308-313
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• 2018

Background: A behavior-based safety initiative card-issuing system was introduced at a cement-manufacturing company in Zimbabwe in 2008 to try and curb accident occurrence. The purpose of this study was to evaluate the effectiveness of the Behaviour Based Safety Initiative card system as a tool used for reducing accident frequencies. Methods: A mixed-method approach that involving administering piloted questionnaires to 40 out of 244 randomly selected employees, making observations, and reviewing secondary data were done to collect data from different sources in the organization in 2013. A paired t-test was conducted to test whether there was significant difference in accident occurrence before and after the implementation of the BBSI. Scatterplots were also used to establish the correlation between the issuance of cards and the accident and injury occurrence. Results: The findings suggest that the introduction of the card system brought a significant decrease in accident and injury occurrence. A negative correlation between card issuance and accident occurrence was observed, i.e., the greater the number of cards issued, the fewer the number of accidents. It was also noted that the card system positively influenced the mindset of workers towards safe work practices. Conclusion: The card system had an influence on the reduction of accidents and injuries. The organization should leverage on issuing more cards to further reduce the number of accidents and injuries to zero.

• Biomolecules & Therapeutics
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• v.19 no.4
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• pp.438-444
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• 2011

The mushroom Coriolus versicolor contains biologically active polysaccharides, most of which belong to the ${\beta}$-glucan group. Diverse physicochemical properties, due to different sources and isolated types of ${\beta}$-glucans, can induce distinct biological activities. We investigated the effects of ${\beta}$-glucans from C. versicolor on phagocytic activity, nitric oxide (NO), TNF-${\alpha}$ production, and signaling of dectin-1, a well-known ${\beta}$-glucan receptor, in macrophages. ${\beta}$-Glucans increased phagocytic activity and TNF-${\alpha}$ and NO-iNOS/eNOS production. Laminarin, a specific inhibitor of dectin-1, showed strong inhibitory effects on phagocytosis and subsequent TNF-${\alpha}$, iNOS, and eNOS production increased by ${\beta}$-glucans, indicating that ${\beta}$-glucans reacts with dectin-1 receptors. We examined whether the aforementioned cytokines were involved in the signaling pathway from the dectin-1 receptor to phagocytosis, and found that the inhibition of iNOS, eNOS, and TNF-${\alpha}$ receptors significantly decreased ${\beta}$-glucan-induced phagocytosis. In conclusion, our study showed that dectin-1 signaling, triggered by ${\beta}$-glucans, subsequently elicited TNF-${\alpha}$ and NO-iNOS/eNOS production, and that these molecules seem to act as secondary molecules that cause eventual phagocytosis by macrophages. These findings suggest that C. versicolor could be used as a nutritional medicine that may be useful in the treatment of infectious disease.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2901-2907
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• 2016

Background: Despite increasing debate about overdiagnosis and overtreatment of thyroid cancer in Korea, information to guide decisions on whether or not to undergo screening for and treatment of abnormal lesions of the thyroid is lacking. Moreover, studies have yet to outline what lay people know and want to know about thyroid cancer. The primary aim of this study was to explore general awareness of thyroid cancer among Korean women, their sources of information, and their satisfaction with the information they are provided. The secondary aim was to investigate information needs about thyroid cancer. Materials and Methods: A qualitative study using focus group interviews was conducted. Twenty-nine women were divided into four groups: (1) participants who had never undergone thyroid ultrasound screening; (2) those who had undergone screening, (3) those who continued to undergo regular check-ups with ultrasonography for benign nodules of the thyroid; and (4) participants who had undergone surgery for thyroid cancer. Results: A widespread lack of awareness of information on thyroid cancer was noted among participants in groups 1 and 2 who were not well aware of thyroid cancer and generally recognized it as a 'good cancer'. Surprisingly, instead of doctors and medical personnel, most participants reported obtaining information from acquaintances and media outlets. Moreover, most participants described dissatisfaction with their experience with screening and a lack of explanation on treatment and test results from medical personnel. Conclusions: Women in Korea seek reliable information on thyroid cancer that could help them to better understand the disease and make informed decisions regarding screening and treatment. More effort is needed from medical personnel to communicate the implications of thyroid cancer, screening results, and treatments thereof to lay people.