• Journal of the Mineralogical Society of Korea
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• v.16 no.3
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• pp.201-213
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• 2003

The adsorption property and ability of domestic zeolites for some heavy metal ions (Ag, Pb, Cr, Cu, Zn, Mn), which may cause a serious environmental problem in industrial wastewater, were evaluated on ore unit through a series of adsorption experiments together with careful examinations of mineral composition and properties of the zeolites. Though the adsorption behavior basically took place in the form of a cation exchange reaction, the higher CEC value does not necessarily to imply the higher adsorption capacity for a specific heavy metal. A general trend of the adsorption selectivity for heavy metals in the zeolites is determined to be as follow: $Ag\geq$Pb>Cr,Cu$\geq$Zn>Mn, but the adsorption properties of heavy metal ions somewhat depend on the species and composition of zeolite. Clinoptilolite tends to adsorb selectively Cu in case of Cr and Cu, whereas heulandite prefers Cr to Cu. A dominant adsorption selectivity of the zeolite ores for Ag and Pb is generally conspicuous regardless of their zeolite species and composition. The zeolite ores exhibit a preferential adsorption especially for $Ag^{+}$ so as not to regenerate when treated with $Na^{+}$ . In the adsorption capacity for heavy meta ions, the zeolites differ in great depending on their species: ferrierite>clinoptilolite>heulandite. Considering the CEC value of mordenite, the mordenite-rich ore appears to be similar to the clinoptilolite ore in the adsorption capacity. The adsorption capacity for heavy metals is not positively proportional to the CEC values of the zeolites measured by the exchange reaction with ammonium ion. In addition, the adsorption capacity roughly tends to depend on the zeolite contents, i.e., the grade of zeolite ore, but the trend is not consistent at all in some ores. These may be caused by the adsorption selectivity for some specific heavy metals, the presence of possible stacking micro-faults and natural cations such as K hardly to exchange in the zeolite. Considering the economic availability and functional effectiveness as natural zeolite resources, clinoptilolite ores could be applicable to utilize the domestic zeolites for the removal of heavy metals.

• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.1-5
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• 1981

In trying to predict the effect of genetics on the broiler in the year 2000, this is a relatively short period of time as far as broiler genetics in concerned. Modern broiler genetics started around 1945 and tremendous gains when made in past 35 years. Futher improvements on broiler will depend on the evolution and revolution: 1. Evolution: (1) Growth rate has been made 4-5% per year. (2) Feed conversion has improved approximately 1% per year. (3) Abdominal fat is becoming a major complaint in broiler. (4) Because of the changing life-style, broiler meat sales in the future will be more and more in cut-up form. (5) Breeding for stress resistance and selection for docile temperament can be important in order to funker improve fled efficiency. (6) In female parent stock, reproduction characteristics are in many can negatively correlated with the desired broiler traits. (7) Egg production and hatchability in moot commercial parent nod m at a fairly high level. (8) In male parent stock, the heavier and mon super-meat-type male lines are desired to Product better broilers. 2. Revolution: Trying to forecast revolutionary change in broiler genetics is highly speculative, as sudden change are aften unpredictable. (1) Species hybridization, such as a turkey-chicken cross (2) Biochemical tools, such as blood typing. (3) Mutation breeding by radiation or chemical mutagentia. (4) Broiler breeding would be to change the phenotypic appearance by single gene, such as naked, wingless. (5) Changes in production techniques. such as growing in cage or growing in filtered air positive pressure houses.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.264-270
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• 2008

Phytic acid(PA) (Inositol hexaphosphate, $IP_6$) is a naturally occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. In the present study, the preventive effects of PA on colon carcinogenesis were investigated. Six-week old Fisher 344 male rats were fed a AIN-93G purified diet and PA(0.5% or 2% PA in water) for 8 weeks. The animals received two ($1^{st}\;and\;2^{nd}$ week) injections of azoxymethane(AOM, 15 mg/kg b.w.) to induce colonic aberrant crypt foci(ACF). After sacrifice, the total numbers of aberrant crypts(AC) and ACF in colonic mucosa were examined after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM induced the total numbers of $142.3{\pm}22.3$ ACF/colon and $336.6{\pm}55.1$ AC/colon. PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dose-dependent manner. The numbers of ACF/colon and AC/colon by PA at the dose of 0.5% were $124.4{\pm}28.5\;and\;302.7{\pm}67.3$, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to $109{\pm}18.1\;and\;254.8{\pm}50.6$, respectively(p<0.01). Especially, 2% PA significantly reduced the number of large ACF(${\geq}4$ AC/ACF) from $26.8{\pm}6.2$ ACF/colon to $15{\pm}6.7$ ACF/colon(p<0.01). Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. These findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in the F344 rat.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.2
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• pp.241-247
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• 2012

Purpose: This study was conducted to assess the association of metabolic syndrome and its components with glaucoma. Methods: We investigated the associations of metabolic syndrome and its components (abdominal obesity, impaired fasting glucose, high blood pressure, and dyslipidemia) with glaucoma using data from 19,162 adults aged 40 or above among the Korean National Health and Nutrition Examination Survey III (2005), IV (2007-9), V (2010). The logistic regression analysis was used for assessing those associations after adjusting demographic, lifestyle, and social economic status and for assessing the association of metabolic medication intakes with glaucoma risks. Results: After adjusting for age and sex, the risk of glaucoma was significantly higher in the subjects with impaired fasting glucose(Odds Ratio (95% confidence interval): 1.78 (1.25, 2.53)) and metabolic syndrome (1.45 (1.01, 2.08)) than subjects without those. These associations increased when additional adjusting for smoking, alcohol use, regular physical activity, income, education status(impaired fasting glucose: 1.89 (1.29, 2.77), metabolic syndrome: 1.52 (1.03, 2.25)). Glaucoma prevalence was borderline significantly increased according to the number of metabolic abnormalities(age and sex adjusted p for trend = 0.055). Use of antihypertensive medication was significantly associated with the risk of glaucoma. Conclusions: Metabolic syndrome and impaired fasting glucose were significantly associated with the increased glaucoma risk. Use of antihypertensive medication was also significantly associated with the increased glaucoma risk.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.18-24
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• 2018

The policy-making and technological development of eco-friendly automobiles designed to increase their supply is ongoing, but the internal combustion engine still accounts for about 95% of the automobiles in use. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. Natural gas is a clean fuel that emits few air pollutants and has been used mainly as a fuel for city buses. In the long term, we intend to develop a new NGOC/LNT+NGCO/SCR combined system that simultaneously reduces the toxic gases, $CH_4$ and NOx, emitted from CNG buses. The objective of this study is to investigate the characteristics of $de-CH_4/NOx$ according to the ceramic and metal substrates of the SCR (Selective Catalytic Reduction) catalysts mounted downstream of the combined system. The V and Cu-SCR catalysts did not affect the $CH_4$ oxidation reaction, the two NGOC/SCR catalysts each coated with two layers began to oxidize $CH_4$ at $400^{\circ}C$, and the amount of $CH_4$ emitted was reduced to about 20% of its initial value at about $550^{\circ}C$. The two NGOC/SCR catalysts each coated with two layers showed a negative (-) NOx conversion rate above $350^{\circ}C$. The ceramic-based combined system reached LOT50 at $500^{\circ}C$, which was about 20% higher in terms of the $CH_4$ conversion rate than the metal-based combined system, showing that the combined system of NGOC/LNT+Cu-SCR is a suitable combination.

• Clinical and Experimental Pediatrics
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• v.49 no.1
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• pp.24-28
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• 2006

Purpose : The purpose of this study was to investigate the health status and nutritional condition of children living in a low-income community through anthropometric, laboratory evaluation. Methods : A community-based survey identified children below 15 years living in a low-income community. Their weight, height, visual acuity, hearing level and dental status were measured. Blood sample were obtained on June and July, 2004. Hemoglobin, serum cholesterol, Hepatitis B antigen/antibody, AST and ALT were measured. Results : A total of 285 students(M : F=141 : 144) aged 6 to 14 years were included in this study. The heights and weights in some grades were smaller than controls. The prevalence of obesity was 10.6 percent in males and 10.7 percent in females. The prevalence of abnormal visual acuity, hearing impairments and dental carries were 20.5 percent, 0.3 percent and 69.4 percent. The prevalence of anemia was 10.1 percent. Serum total cholesterol was over 200 mg/dL in 7 percent. They complained of abdominal pain(22.1 percent) and headache(17.1 percent). Hyperthyroidism, cataract, neurofibromatosis, severe atopic dermatitis, ventricular septal defect, strabismus and inguinal hernia were newly diagnosed. Conclusion : Mean heights and weights of children in the low-income community were smaller than controls. The prevalence of abnormal visual acuity, hearing impairment and dental carries were higher than in the 2003 national health survey. Additional research is needed to evaluate the health status of the low-income community.

• Korean Journal of Heritage: History & Science
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• v.53 no.3
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• pp.110-127
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• 2020

The term "conserved remains" refers to cultural remains that are preserved in accordance with the valuation of buried cultural properties when important remains are recognized in rescue excavations during construction work. South Korea's rapid economic growth and ensuing land development over the past few decades compelled a sharp increase in the number of rescue excavation cases, and, naturally, of conserved remains. Today, an increasingly large number of conserved remains have raised issues, including those concerning land expropriation as well as the management and utilization of such remains, but no clear solutions have been proposed. This study attempts to propose plans for improvement based mainly on the recognition of institutional issues rather than technical issues related to the conservation of cultural remains. This is because the identification and review of institutional deficiencies must be prioritized in order to efficiently manage conserved remains with limited resources and manpower. Among many possible proposals to demand improvement of conservation policies, one that must first be examined under the current system is the rapid transition, or review thereof, of "conserved remains" to "designated cultural properties." Unlike designated cultural properties, conserved remains are merely a temporary means of conservation, because they lack regulations for follow-ups subsequent to preliminary measures. Naturally, deferring the definition of relics as "conserved remains" for extended periods causes numerous problems. Measures to resolve such problems may include establishing a legal system to manage conserved remains at a level similar to designated cultural properties or seeking ways to improve management under the current system. This study focuses on areas where institutional improvement for conserved remains is possible by methods other than through the rapid transition to designated cultural properties and presents several proposals. Currently, conservation measures are divided into three categories: on-site conservation, relocation conservation, and record conservation. This study reclassifies these categories from three into four categories. On-site conservation includes only two categories: conserved remains and the newly-proposed soil-covered remains. Two remaining categories, the relocation conservation remains and the record conservation remains, are presented as classifications in which development projects are possible, and they are presented as alternative conservation types that contrast with on-site conservation. Unlike conserved remains, soil-covered conservation presented as a new category in which development projects are possible.

• Economic and Environmental Geology
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• v.37 no.5
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• pp.555-568
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• 2004

The demand of aggregate resources in Korea has been increased with a rapid economic growth since the 1980s. About 25% of the total aggregate production is derived from riverine aggregates, 20% to 25% from marine sands, 40% to 45% from crushed aggregate and the rest 5% to 15% from old fluvial deposits. The abundance of crushed coarse aggregates varies in the uniform distribution of country, but in general it can be concentrated in the most densely populated areas, five main cities. Typical rock types of the Korean crushed stones are classified as plutonic rocks of 27%, metamorphic rocks of 32%, sedimentary rocks and volcanic rocks of 18%, respectively. The most abundant coarse aggregate used in the country is obtained from granite (25% of total) and subordinately gneiss (20%), sandstone (10%) and andesite (10%). Although rock types using as dimension stone are only fifteen, those as aggregate amount up to twenty nine rocks. These rocks consist of plutonic rocks such as granite, syenite, diorite, aplite, porphyry, felsite. dike and volcanic rocks such as rhyolite, andesite, trachyte, basalt, tuff, volcanic breccia and metamorphic rocks such as gneiss, schist, phyllite, slate, meld-sandstone, quartzite, hornfels, calc-silicate rock, amphibolite. And sandstone, shale, mudstone, conglomerate, limestone, breccia, chert are main aggregate sources in tile sedimentary rocks. The abundance of plutonic rocks is the highest in Chungcheongbuk-do, and decreases as the order of Jeollabuk-do, Gangwon-do and Gyeonggi-do. In Jeollanam-do, volcanic aggregates occupy above 50%, on the contrary sedimentary aggregates are above 50% in Gyeongsangnam-do.

• Journal of Preventive Medicine and Public Health
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• v.25 no.1 s.37
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• pp.1-12
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• 1992

To assess the pattern of psychiatric symptoms and to evaluate the relationship between exposure related variables(duration of work and urinary hippuric acid concenturation) and psychiatric symptoms in organic solvent exposed workers, case control study of forty-two solvent exposed workers and ninethy-six non-exposed workers was conducted. The general health questionnaire 28(GHQ28) was administered to evaluate psychiatric symptoms and urinary hippuric acid concenturations was measured to estimate the present status of solvent exposure in exposed group and to estimate normal level in non-exposed group. The mean concenturation of urinary hippuric acid was significantly higher in exposed group (2.953g/creatinine g) than non-exposed group(0.395g/creatinine g) (P<0.01). The total positive rates of symptoms were significantly higher in exposed group(28.2%) than non-exposed group(17.5%)(P<0.05). The positive rates of symptoms for four sub-scales of GHQ28 in exposed group were in the order of somatic symptoms, anxiety, social dysfunction, depression and in the order of social dysfunction, anxiety, depression, somatic symptoms in non -exposed group. The positive rates of symptoms for somatic symptoms and anxiety were significantly higher in exposed group than non-exposed group (P<0.05) and the proportion of workers with six or more positive symptoms(dysthymic states) in exposed group were significantly higher than non-exposed group (P<0.01). After the effect of age, sex, level of income, level of education, and duration of work were controlled, the total score of GHQ28 was still significantly different between exposed and non-exposed group(P<0.01). In multipile logistic regression analysis on the dysthymic state, the odds ratio of level of income was statictically significant in both group. The odds ratios of exposure related variables such as duration of work and hippuric acid concenturations were not statistically significant but there was a tendency that exposure related variables had an affect on dysthymic state in exposed group. In future, continuous evaluation of psychiatric symptoms on organic solvent exposed workers and studies to detect the factors that affect on psychiatric symptoms are required.

• 한국지구물리탐사학회:학술대회논문집
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• 2000.09a
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• pp.54-69
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• 2000

There are groundwater trouble by high-salinity yield inducing sea-water intrusion in Cheju Island. It is used groundwater-GIS(Well-lnfo) in the maintenance and management of groundwater in Cheju Island to grasp groundwater trouble area and cause of high-salinity yield. For 16 wells certain to yield high-salinity, we logged specific electrical conductivity(EC) and tried to get hold of freshwater and saltwater relationship. As result of distribution of $Cl^-$ by depth, it is showed up groundwater trouble by high-salinity yield in the east coastal area and the partly north coastal area. The reason of high-salinity groundwater yield are low-groundwater level by the structure of geology and low-hydraulic gradient etc. There is necessity for management to development and use of groundwater in the high-salinity area, special management area.