• Applied Microscopy
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• v.35 no.3
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• pp.165-176
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• 2005

Studies on molecular plasticity of Bermann glia (BG) after harmaline-induced Purkinje cell (PC) degeneration in the rat cerebellum. The intimate structural relationship between BG and PC, evidenced by the sheathing of the PC dendrites by veil-like process from the BG has been suggestive of the close functional relationship between these two cell types. However, little is known about metabolic couplings between these cells. This study designed to investigate molecular plasticity of BG in the rat cerebellum in which PCs were chemically ablated by harmaline treatment. Immunohistochemical examination reveals that harmaline induced PC degeneration causes a marked glial reaction in the cerebellum with activated BG and microglia aligned in parasagittal stripes within the vermis. In these strips, activated BG were associated with upregulaion of metallotheionein, while GLAST and was down regulated, as compared with nearby intact area where both BG are in contact with PCs. The data from this study demonstrate that BG can change their phenotypic expression when BG loose their contact with PCs. It is conceivable that activated BG may upregulate structural proteins, metallothionein expression to use for their proliferation and hypertrophy; metallothionein expression to cope with oxidative stress induced by PC degeneration and microglial activation. On the contrary, BG may down regulated expression of GLAST because sustained loss of contact with PCs would eliminate the necessity for the cellular machinery involved glutamate metabolism. In conclusion, BG might respond man to death of PCs by undergoing a change in metabolic state. It seems possible that signaling molecules released from PCs regulates the phenotype expression of BG. Also ultrastructures in the organelles of normal PC and BG are distinguished by mitochondrial appearance, and distributed vesicles at the synaptic area in the cytoplasm.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.214-223
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• 2017

A total of 15 different corn hybrids, Kwangpyeongok, Gangdaok, Yanganok, Singwangok, Jangdaok, Cheonganok, Cheongdaok, Andaok, Dapyeongok, Pyeongkangok, Pyeonganok, Daanok, Sunwon 184, Gangilok, and P3394 was used to investigate the growth and yield depending on the sowing date. The sowing dates were April 5, June 25, and July 5 and each experiments was performed in triplicste. The growth of Gangdaok was the highest. However, although the growth of Kwangpyeongok, was lower thanthar of Gangdaok, its stem height to ear height ratio was lower than that of Gangdaok, thus, Kwangpyeongok may be more suitable for stable cultivation. Both growth and yield of Daanok were low, regardless of planting date, but yield and ear shape of Pyeongkangok and Dapyeongok were for fresh corn. Growth and yield of the 15 different corn hybrids varied depending on the planting date, However, the growth degree days (GDD) was the most important factor governing the maturity of corn. More than $1500^{\circ}C$ of GDD was sufficient to harvest mature corn hybrids in the central region of Korea. Besides yield and growth, other characteristics, such as sweetness and taste of the hybrids, should be investigated further the selection of the best corn hybrid.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.587-604
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• 2007

In order to investigate the vertical variations and speciations of trace elements, and their correlations in Hoidong reservoir, sediment cores (21-41 cm below surface) and interstitial water samples were collected from five sampling locations. The total average concentrations of trace metals in sediment core samples were $232{\pm}30.8mg/kg$ for Zn, $119{\pm}272mg/kg$ for Cu, $58.4{\pm}4.1mg/kg$ for Pb, $15.7{\pm}3.3mg/kg$ for Ni and $1.6{\pm}0.3mg/kg$ for Cd. The total concentrations of trace metals in core sediments generally decreased toward the center of the Hoidong reservoir. The total concentrations of Mn, Pb and Zn decreased with depth for all the sample locations, while Cu and Fe concentrations increased. The trace metal concentrations of interstitial water sample were in the order of Fe>Mn>Cu>Zn, but Cd, Ni and Pb were not detected. The concentrations of Zn, Cu, Fe and Mn in the interstitial water samples showed a tendency of increasing toward the bottom of the core, suggesting a possible upward diffusion. This migration of trace metals may lead to their transfer to the sediment-water interface. These trace elements would be subsequently fixed onto amorphous Fe and Mn-oxides and carbonates in the topmost layer of sediment. Based on the $K_D$ values, the relative mobilities of the studied metals were in the order of Mn>Cu>Zn>Fe. Geochemical partitioning confirmed that surface enrichment by trace metals mainly resulted from a progressive increase of the concentrations in the fractions II and III. Copper, Fe, Mn and Zn concentrations of interstitial water were closely correlated with their exchangeable fractions of sediments.

• Journal of Animal Science and Technology
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• v.53 no.2
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• pp.113-118
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• 2011

This study was conducted to evaluate effects of enzyme complex on growth performance, nutrient digestibility, blood profiles and feed cost in growing pigs. Ninety-six pigs [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc, $22.96{\pm}0.79$ kg average initial body weight] were used in 42d growth assay. Dietary treatments included:1) HC (high energy and nutrient density diet), 2) CON (control, basal diet), 3) CE1 (CON + 0.05% enzyme complex) and 4) CE2 (CON + 0.1% enzyme complex). Four pigs were allotted per pen with six replicate pens per treatment by completely randomized design. The ADG was higher in CE1 and CE2 treatments than CON treatment (P<0.05). The ADFI was linearly increased by CE treatments compared to HC treatment. The CE1 treatment had highest DM, N and GE digestibility (P<0.05). Digestibility of DM, N and GE were quadratic enhanced by enzyme complex level. No differences were found among treatments for creatinine and BUN. The enzyme complex treatments (CE1 and CE2) showed lower feed cost/body weight gain than HC treatment. In conclusion, enzyme complex can improve ADG and reduce feed cost/body weight gain when low energy diet was used. Furthermore adding 0.05% enzyme complex had highest nutrient digestibility.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.166-170
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• 2000

Three methods for heat collection, which were the flat solar collector, two fan with radiator, and square pipe method, were studied to sue efficiently solar energy in the three different glasshouses for two years. The flat plate solar collector method was made use of the commercial solar collector with collection area of 24$m^2$, the method of two fans with radiators collected solar energy at the top of the glasshouse. An thermal storage tank was constructed underneath in teach glasshouses. When an area of 1,000$m^2$ was heated to the minimum temperature of 9$^{\circ}C$, the decrease rate of heating fuel for the flat plate solar collector, the fan attached radiator and the square pipe methods were 7%, 19% and 28% respectively. The flat plate solar collector method, which could be heated approximately 40-50$m^2$, was currently used by most of the farmer. Under the condition, the decrease rate of annual heating fuel was 14% which was not better for an economic annual heating fuel. If the fan with radiator method was operated, the use of installation and maintenance were required. So, it could not be good economic efficiency of solar heating. The heating efficiency of the square pipe method was relatively better thant those of the flat plate solar collector or the fan attached radiator. Since the cost of materials and its installation of the use of square pipe method was lower than any other method. However, corrosion of the pipe, greater shade in the greenhouse and strength against the square pipe were problems that should be overcome in the square pipe method.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.125-130
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• 2009

The aim of this study was to investigate whether differences in the distribution of soil invertebrates among different vegetation types (forest, reservoir, and crop land types) in rural area. A total of 18 orders and 137 species were collected by pitfall traps. Species numbers were the lowest (33 species) at the Chamaecyparis obtusa plantation (St. 6). On the forest sites, the individual number of Hymenoptera was the most abundant, and Acari and Coleoptera was the relatively more abundant than the other sites. On the reservoir sites (Salix chaenomeloides community), the individual number of Collembola was the most abundant, and Diptera was the relatively more abundant than the other sites. On the crop land sites, the individual numbers of Collembola, Hymenoptera, and Araneae were the relatively more abundant than the other orders. The density of Araneae was higher in the reservoir and crop land sites than in the forest sites. From a point of view of biodiversity, although the diversity index(H') was the highest in the mixed broad-leaved forest type (St. 2) with Quercus serrata and Q. acutissima, and the lowest in the upland levee of crop land(St. 11), there was no significant difference among the habitat or vegetation types. According to the community analysis, the soil invertebrates could be divided into 4 groups, the mixed broad-leaved forest type (A group), the plantation or pure forest type (B group), the reservoir type (C group), and the crop land type (D group).

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.4
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• pp.265-273
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• 2005

Chemical properties and heavy metal concentrations of forest soils of four abandoned coal mine lands affected by coal mining activities in the Mungyeong area were investigated to provide basic information for revegetation of abandoned coal mine lands. Soil pH in abandoned coal mine lands ranged from 5.30 to 6.76 it in the control site was 5.23. Contents of organic matter and total N in abandoned coal mine lands were $4.46\~7.19\%\;and\;0.07\~0.15\%$, respectively. Available P contents were 6.54 for A (Samchang), 6.52 for B (Bongmyeong),3.94 fur C (Kabjung), 5.45 mg/kg for D (Danbong coal mine land) and 5.25 mg/kg for the control site, which had a positive correlation with soil pH. Contents of exchangeable Ca, Mg, K and Na in abandoned coal mile lands averaged 196.1, 88.7, 88.2 and $10.2cmol^+/kg$, with a range of $132.1\~242.1,\;24.2\~138.\; 64.9\~120.8\;and\;8\~12.2cmol^+/kg$, respectively. Those of the control site were 192.8, 95.8, 104 and $21.2 cmol^+/kg$, respectively. Heavy metals such as Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn of forest soil in abandoned coal mine lands have a larger content than those of the control site. Al, Mn and fb content was especially high in abandoned coal mine lands. The Al content of forest soil in abandoned coal mine lands ranged from 397 to 917 ppm, which was considered to be high enough to inhibit tree growth. Therefore, it is suggested that soils of abandoned coal mine lands contaminated by mining activities need to be properly treated for remediation of environmental problems.

• Journal of Dairy Science and Biotechnology
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• v.34 no.4
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• pp.255-262
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• 2016

This study was conducted to investigate the difficulties of dairy farms in practicing 6th industrialization and methods for overcoming these difficulties. A qustionnaire survey was carried out to examine the present states of farms, recognition of the farmstead milk-processing market situation, possibility of farmstead milk processing for reducing the raw milk surplus, assessment of government policies, and difficulties dairy farmers confront in realizing the 6th industrialization. Farm sizes, types, and human resources organizations varied between farms. Most farmers were producing yogurt and/or fresh (string or barbecue) cheeses, which were marketed through 'Visit and Purchase' channel. Farmers who answered the questionnaire were relatively positive about the current situation of farmstead milk processing, expecting to be involved in the disposal of excess raw milk. Nevertheless, they responded negatively about current relevant policies, citing the main difficulties caused by 'excessive regulation'. Other barriers to successful '6th industrialization' are difficulties in marketing and lack of funds. Approximately 19% of dairy farms practicing the '6th industrialization' use automatic milking system (AMS) and 38.46% of dairy farmers whose milking depends on conventional milking system intend to introduce AMS in the future. Positive expectations of AMS adoption were mostly related to 'lack of time and labor', 'exhibiting for tourism', and 'succession of dairying'.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.168-179
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• 2002

The purpose of this study was to find a method for improving the children's behavior during dental treatment in relation with dentist's attire. For this study 150 children, visiting a dental clinic, were asked to participate in a survey on the attire of the dentist. The results of the survey were as follows: 1. In the survey for the preference between gown and ordinary clothes according to sex(P<0.05), age(P<0.05), residence (P<0.05) and number of visits(P<0.05), there was more preference for gown(65.3%). 2. The preference for the type of gown and attire under the gown was a long gown and white shirt (30.7%), followed by a suit-like gown (18.7%) and white shirt, and long gown and polo shirt(17.3%). 3. The preference for the color of gown was white(34.7%), followed by pink (18.7%), green(18.0%), blue(15.3%) and yellow(13.3%). 4. The preference for the pattern on the gown was cartoon characters(49.3%), followed by hospital logo(28.7%) and no pattern(14.7%). 5. The preference for ordinary clothes of female dentists was polo shirt(37.3%), followed by striped shirt(28.7%), round T-shirt(18.7%), and everyday Korean traditional dress(15.3%). 6. The preference for ordinary clothes of male dentists was pattern necktie and no pattern Y-shirt(28.0%), followed by no pattern necktie and Y-shirt(21.3%) or pattern shirt with no necktie, and no pattern Y-shirt with no necktie(14.7%). 7. The preference on the protective equipment worn was mask and glove(28.7%), followed by no protective equipment(26.7%), mask, glove and protective glasses(22.7%) at)d only mask(22.0%). Based on the above results, it seems that parting with the traditional white gown and wearing multi-color and pattern attire will provide psychological stability and help improve children's behavior during treatment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.846-853
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• 2016

This study prioritizes Noxious Liquid Substances (NLS) transported by sea via a risk-based database containing 596 chemicals to prepare against NLS incidents. There were 158 chemicals transported in Korean waters during 2014 and 2015, which were prioritized, and then chemicals were grouped into four categories (with rankings of 0-3) based on measures for preparedness against incident. In order to establish an effective preparedness system against NLS spill incidents on a national scale, a compiling process for NLS chemicals ranked 2~3 should be carried out and managed together with an initiative for NLS chemicals ranked 0-1. Also, it is advisable to manage NLS chemicals ranked 0-1 after considering the characteristics of NLS specifically transported through a given port since the types and characteristics of NLS chemicals relevant differ depending on the port. In addition, three designated regions are suggested: 1) the southern sector of the East Sea (Ulsan and Busan); 2) the central sector of the South Sea (Gwangyang and Yeosu); and 3) the northern sector of the West Sea (Pyeongtaek, Daesan and Incheon). These regions should be considered special management sectors, with strengthened surveillance and the equipment, materials and chemicals used for pollution response management schemes prepared in advance at NLS spill incident response facilities. In the near future, the risk database should be supplemented with specific information on chronic toxicity and updated on a regular basis. Furthermore, scientific ecotoxicological data for marine organisms should be collated and expanded in a systematic way. A system allowing for the identification Hazardous and Noxious Substances (HNS) should also be established, noting the relevant volumes transported in Korean waters as soon as possible to allow for better management of HNS spill incidents at sea.