• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.1-11
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• 2004

Foam reduces the mobility of gas phase in porous media to overcome gravity override and to divert acid into desired layers in the petroleum industry and to enhance the efficiency of environmental remediation. Recent experimental studies on foam show that foam exhibits a remarkably different flow rheology depending on the flow regime. This study, for the first time, focuses on the issues of foam diversion process under the conditions relevant to groundwater remediation, combining results from laboratory linear-flow experiments and a simple numerical model with permeability contrasts. Linear flow tests performed at two different permeabilities (k = 9.1 and 30.4 darcy) confirmed that two flow regimes of steady-state strong foams were also observed within the permeability range of shallow geological formations. Foam exhibited a shear-thinning behavior in a low-quality regime and near Newtonian rheology in a high-quality regime. Data taken from linear flow tests were incorporated into a simple numerical model to evaluate the efficiency of foam diversion process in the presence of permeability contrasts. The simple model illustrated that foam in the high-quality regime exhibited a successful diversion but foam in the low-quality regime resulted in anti-diversion, implying that only foam in the high-quality regime would be applicable to the diversion process. Sensitivity study proved that the success of diversion process using foam in the high-quality regime was primarily controlled by the limiting capillary pressures (${P_c}{^*}$) of the two layers of interest. Limitations and implications are also discussed and included.

• Journal of Fashion Business
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• v.15 no.5
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• pp.43-54
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• 2011

Digital Textile Printing(DTP) is appropriate for quick response system(QRS) and is closely connected with high value added fashion industry. Fashion products of high price are mainly silk and cotton. For high quality DTP products, it is important to optimize the parameters of media, pre and after-treatment, ink, printer, etc. DTP for these two fiber materials is also accompanied certainly with steaming as after-treatment process for coloration. Role of steam is like water in exhaustion dyeing. Steam can diffuse dye or ink in printing paste to fiber. Quality of DTP products depend on after-treatment processes such as steaming, washing, drying. Current production amount of DTP is smaller than one of conventional textile printing. However conventional after-treatment system has been using so far. This is mismatched with DTP in terms of process efficiency, spot work of small lot, quality control. In this study, continuous after-treatment system has been suitably designed for DTP that washing and drying are available after steaming. So, It is possible to improve efficiency of DTP process. Especially, the effects of after-treatment process, such as temperature of heat drum, steaming time on printability, color difference, color fastness were examined. Two types of samples(cotton knit and silk fabrics) were used. The results were obtained as follows : First, there is no a wide difference between the K/S values of cotton and silk treated with continuous after-treatment system and those of sample treated with conventional printing after-treatment method. So it is more effective to use the continuous after-treatment system than conventional printing after-treatment system in case of the daily throughput of 1,000 yards below. Second, after continuous after-treatment for DTP, K/S values were increased and lightness($L^*$) values were decreased. ${\Delta}E$ values were below 2.3. Third, DTP samples treated with continuous after-treatment system were tested for fastness(washing, light, rubbing). Grades of fastness(washing, light, rubbing) were above 3 grade.

• Development and Reproduction
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• v.13 no.3
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• pp.163-172
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• 2009

Some organotin compounds such as butyltins and phenyltins are known to induce impo-sex in various marine animals and are considered to be endocrine disruptors. In this study, the effect of organotins on follicular steroidogenesis in amphibians was examined using ovarian follicles of Rana dybowskii and Rana catesbeiana. Isolated follicles were cultured for 6 or 18 h in the presence and absence of frog pituitary homogenate (FPH) or various steroid precursors, and the levels of product steroids in the culture media oassay. Among the butyltin compounds, tributyltin (TBT) strongly and dose-dependently inhibited the FPH-induced synthesis of pregnenolone ($P_5$) and progesterone ($P_4$) by the follicles. TBT also strongly suppressed the conversion of cholesterol to $P_5$ and partially suppressed the conversion of $P_5$ to $P_4$. A high concentration of dibutyltin (DBT) also inhibited steroidogenesis by the follicles while monobutyltin and tetrabutyltin had negligible effects. The toxic effect of TBT or DBT was irreversible and a short time of exposure (30 min) was enough to suppress steroidogenesis. All the phenyltin compounds significantly inhibited FPH-induced $P_5$ synthesis by the follicles. The effective dose of 50% inhibition by diphenyltin was $0.04\;{\mu}M$ and those of monophenyltin and triphenyltin were $0.24\;{\mu}M$ and $0.3\;{\mu}M$, respectively. However, none of the phenyltin compounds significantly suppressed the conversion of $P_4$ to $17{\alpha}$-hydroxyprogesterone ($17{\alpha}$-OHP) (by $17{\alpha}$-hydroxylase), $17{\alpha}$-OHP to androstenedione (AD) (by $C_{17-20}$ lyase), or AD to testosterone by the follicles. Taken together, the data show that among the steroidogenic enzymes, P450scc in the follicles is the most sensitive to organotin compounds and that an amphibian follicle culture system can be a useful screening model for endocrine disruptors.

• Journal of Science Education
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• v.37 no.2
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• pp.294-309
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• 2013

This study addressed the awareness of social issues related to science of future elementary school teachers. Fukushima Nuclear Power Plant Accident was used by concrete issue connected with SSI for this study. Twelve second-year students attending a university of education participated in the study, who were taking a class of science teacher preparation at that time that consists of the content of the elementary science education courses. The study revealed that all the pre-service elementary teachers recognized Fukushima Nuclear Power Plant Accident and received such information through various medias. In particular, they were receiving more information about the Nuclear Power Plant Accident through the internet than any other media by using the internet a lot, and also gained additional information through the internet. However, despite the fact that they recognized Nuclear Power Plant Accident, they neither had much information about it nor had been interested in SSI such as the Nuclear Power Plant Accident. Moreover, they had been basically uneducated about SSI. Despite of having no interest in SSI such as Nuclear Power Plant Accident, the study revealed that the pre-service elementary teachers recognized that scientific problems such as Nuclear Power Plant Accident may affect a society closely. In addition, they together sympathized with the point that SSI education should be applied on the current education courses by identifying the problem in application. As the study revealed above, the application of SSI education to the formal education courses as well as more lively research on that subject is very important and urgent for boosting interest in science subjects and enlightening the nature of science that is one of the objectives of science education.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.281-285
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• 2015

An oleaginous fungus was isolated from soil and identified as Mortierella sp. (M-12) for producing arachidonic acid (AA). Cell disruption methods, extraction methods, and particle sizes of freeze-dried biomass were tested to achieve maximum extraction of total lipids and AA. M-12 grown in glucose yeast media at $25^{\circ}C$ for 7 days contained 35.5% total lipid, and 47% of the total lipid was AA. Lipid extraction yield from wet biomass was shown to be similar to that in a dry state. Maximum lipid extraction was achieved using a mixture of chloroform and methanol (2:1) as an extraction solvent. Different mechanical cell disruption methods did not affect lipid extraction yields. The smaller the particle size of the biomass, the better the lipid extraction yield was observed. Particle size of biomass was shown to more strongly affect lipid extraction than extraction time. The highest AA content was observed in the class of neutral lipids.

• Journal of The Korean Society of Integrative Medicine
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• v.1 no.4
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• pp.37-47
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• 2013

PURPOSE : Club dance is one of the most popular cultures worldwide and is getting popular in Korea over time. However, club still has negative awareness in the country due to the media spreading only harmful aspects of club culture. At any rate, nowadays many young aged people can easily have chances to experience clubs so we tried to find out the bad effects caused by clubs. METHOD : We conducted a survey and the number of participants who agreed to participate in this survey was 500, including both men and women. There are a total of 50 questions in the questionnaire form used by this study and the questions were divided into three categories: general(18), psychologic-related(7), social-cultural(9), and physical-related(16) questions. Data collected for this study was analyzed via frequency analysis using SPSS. RESULT : In our survey, most students who had already experienced the club culture tend to go to club once or twice a month, and they answered that they would feel bored if they were nor able to do so. In terms of social life, most respondents said that they had lower efficiency in working and studying the next day after going to clubs because of fatigue. In physical aspect, club users use then pelvis and lower back a lot while dancing. The respondents answered that they experienced muscle soreness, a loss in weight, and changes in their body as a consequence of intense dancing. They complaint pain mostly in lower limbs, so we could find out the fact that legs were primarily used for the club dance. CONCLUSION : To sum up, the club culture in undergraduate students affects on their daily living and body, and also has good effects as well as bad ones. Therefore, we need to look at the club culture positively and to improve bad effects of club culture.

• Journal of Korean Home Economics Education Association
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• v.19 no.3
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• pp.119-131
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• 2007

This study was to investigate the recognition level of food safety from high school students(264 male, 276 female) in Chuncheon area using questionnaires. The results of the survey are summarized as follows : Regarding the general consciousness of the conditions of food safety, the proportion of the students who worry about it is higher, while 40.0% respond they are not concerned with it. The information pertinent to food safety was usually acquired from the mass media. As a fundamental reason responsible for the food safety accidents, they pointed out deficient sense of responsibility of the personnels who produce, distribute, and sell food products. As the most problematic materials threatening food safety, they pointed out heavy metals(24.8%), and subsequent responses were environmental hormones(24.4%), food additives(17.0%). The foods, for which they are most concerned about residual pesticides, were vegetables and fruits. High proportion of the students perceived that agricultural products are not safe from residual pesticides, and most of the students(92.4%) thought that residual pesticides are bad for their health. The examination on the food safety influenced by heavy metals reveals that 87.4% of the students thought the materials do influence food safety. As the food kind that is likely to be most polluted by heavy metals, they pointed out fishery products. The highest concern about processed food stuffs was the food additives. Most of the students thought that the containers of processed foods may be toxical. 25% of the students are more seriously considering food safety when they buy foods. High proportion of the students who responded they confirm safety-related matters at the time of food purchase thought much of food safety, while high proportion of those who didn't confirm those matters lay a great importance on the taste.

• Journal of Oral Medicine and Pain
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• v.34 no.1
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• pp.39-48
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• 2009

Recently there is much interest in the antibacterial activity of nano-sized silver particle (nanosilver) since silver is known to be safe and effective as disinfectant for a long time. Oral malodor is considered to originate in the oral cavity primarily as a result of production of malodorous compounds by oral bacteria. Major compounds responsible for oral malodor are volatile sulfur compounds, which is thought to be generated by the G(-) anaerobic bacteria found normally in the oral cavity, especially on the dorsum of the tongue. The purposes of this study were to investigate the effect of nanosilver on growth of oral malodor generating microorganisms, including Fusobacterium nucleatum, Prevotella melaninogenica, Klebsiella pneumonia, and to determine the optimal culture condition of them. The results were as follows: 1. The optimal culture condition for P. melaninogenica was vacuum culture using desiccator after evacuation of air by vacuum pump in chopped beef meat media. 2. The growth of K. pneumonia was temporarily inhibited by nanosilver (5 ppm and 10 ppm). 3. The morphological alteration and cell damage caused by nanosilver were observed in K. pneumonia.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.189-201
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• 1976

In an effort to develop a microbial in secticide, B. thdringiensis var. thuringiensis was cultured in the medium composed of cocoon-cooked water from a filature. The results obtained are summarized as followss : (1) Bacillus thuringiensis is a bacterium producing a ${\delta}-endotoxin$ especially toxic to lepidopterous insects and a thermostable exotoxin harmful to dipterous insects. (2) With a view to utilizing the cocoon-cooked water discarded from the filature, as a nutrient source in the B. thuingiensis culture, it was analyzed to contain large amounts of various minerals and protein (7.5 mg/ml) believed to be extracted from the pupae. (3) A large amount of the ${\delta}-endotoxin$ can be obtained most cheeply by using cocoon-cooked water instead of distilled water in preparing GYS and citrate salts media. (4) The largest amount of a mixture of the vegetative cells, spores, and crystals was obtained by addition of 8 gr/l of glucose to the GYS medium. (5) The growth of the bacterium was far better, when leucine, isoleucine, and valine were added all together to the citrate salts medium to the concentration of $1.25{\times}10^{-3}M$. (6) The best growth was observed by addition of Na-glutamate to the citrate salts medium to the concentration of $2.5{\times}10^{-3}M$. (7) The optimal culture time ranged from 9 to 15 days. (8) The highest mortality was shown in Pieris rapae Linne with a pH of the total body extract of 8.4, whereas Dendrolimus spectabilis Butler and Bombyx mori Linne with lower pH's were less susceptible to the ${\delta}-endotoxin$. (9) The presence of the thermo stable exotoxin was confirmed by the fact that the supernatant of the culture was very toxic to the Drosophila melanogaster tested.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.49-54
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• 2009

Cultivation characteristics of 12 strains of cauliflower mushroom (Sparassis crispa) collected in Korea were investigated by growing the mushroom on sawdust medium of Larix kaempferi. As cultivation characteristics, incubation period for full growth of mycelium in a cultivation bottle, cultivation time period taken for first harvest, and mushroom color and yield were examined. S. crispa KFRI 723 showed the shortest for incubation period with 59 days while S. crispa KFRI 746 showed the longest with 94 days. The earliest mushroom harvesting was achieved by 29 days from S. crispa KFRI 746 and the latest was by 63 days from S. crispa KFRI 691. The colors of fruit body of the tested strains can be divided into three groups; S. crispa KFRI 700 was white, S. crispa KFRI 747 was yellow brown, and the others were light yellowish. KFRI 700 yielded the most as 163 g from 380 g sawdust media, while KFRI 746 and KFRI 747 were the lowest with 58 g and 35 g, respectively. As results of cultivation characteristics of 12 strains of cauliflower mushroom, we consider that three strains (KFRI 700, 723 and 724) of S. crispa are suitable for sawdust cultivation on L. kaempferi in the aspects of mycelial growth period, harvesting period and mushroom production, respectively.