• Journal of Industrial Technology
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• v.2
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• pp.33-44
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• 1982

This study mainly concentrated on the treatment of nightsoil by an anaerobic filter media process. Nightsoil has been one of the major water pollutants in this couotry. It represents high ROD and SS concentrations. A comprehensive laboratory study conducted at Kangwoon National University indicate: (1) In the case of anaerobic filter system, COD and BOD removal efficiencies were greatly influenced by hydraulic retention time(HRT), but SS removal efficiencies dropped slowly when HRT were 2~13 days. (2) COD removal efficiencies were 19% when HRT were 15 days, 14% when HRT were 8 days, 10% when HRT were 6 days, 9% when HRT were 4 days, 2% when HRT were 2 days. (3) BOD removal efficiencies were 23% when HRT were 15 days, 14% when HRT were 8 days, 18% when HRT were 6 days, 7% when HRT were 4 days, 5.8% when HRT were 2days. (4) SS removal efficiencies were 21%~25%(2~15 days HRT).

• KSBB Journal
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• v.18 no.3
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• pp.234-238
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• 2003

Biofilm process is preferred to activated sludge process in small domestic wastewater treatment plant because of its simplicity in operation and maintenance. Column reactor filled with waste ceramics and with waste plastics was used to remove pollutants in restaurant wastewater. COD removal at 18 hours of hydraulic retention time (HRT) gave 93.7%, COD removal during the experimental period, where maximum COD removal was observed. Under same condition, average removal of total nitrogen and total phosphorus were 82.3% and 25.9%, respectively Organic and nitrogen were efficiently removed with the HRT of 18 hours or more.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.27-35
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• 1986

This study was devised to observed the growth inhibition and change of disaccharidase activities of human colon cancer cells cultured in medium containing the ginseng extract. Three species of human colon cancer cell lines, HRT-18, HCT-48 and HT-29, were used for the experiment. The activities of sucrease, lactase, maltase and trehalase in the cancer cells were determined. The results obtained are summarized as follows; 1. The doubling times of the HRT-18, HT-29 and HCT-48 were about 20,22 and 24 hours, respectively. 2. The growth rates of the HRT-18 and HCT-48 in culture medium containing the ginseng extract were inhibited gradually according to increase of the concentration of ginseng extract and extension of the incubation time. 3. The activities of disaccharidase in HRT-18 and HCT-48 cultured in the medium containing the ginseng extract were increased compared with control group as follows;

• The Korean Journal of Rehabilitation Nursing
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• v.16 no.1
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• pp.18-26
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• 2013

Purpose: This study was conducted to identify menopausal symptoms and quality of life (QOL) according to hormone replacement therapy (HRT) in rural menopausal women. Methods: Menopausal symptoms and QOL were measured by questionnaires. A total of 50 participants in HRT group had received hormone replacement therapy for 12 weeks and another 50 who had not received hormone therapy were assigned to non-HRT group. Results: Vasomotor symptom score of non-HRT group was significantly higher than that of HRT group (p=.013). There were no statistically significant differences between two groups in all menopausal symptoms except for vasomotor symptom. There were no significant differences between two groups in the total scores and sub-scores of QOL. Total scores and sub-scores of QOL were very low in both group. Menopausal symptoms were significantly negatively correlated with QOL. Conclusion: These results showed that there were no statistically significant differences between HRT group and non-HRT group in menopausal symptoms except for vasomotor symptom and QOL. Menopausal symptoms were moderate and QOL was very low in menopausal women. It is necessary to develop nursing interventions to improve menopausal symptoms and QOL in menopausal women.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.256-263
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• 2010

The study was performed to evaluate the effects of chloride concentrations on the ultimate aerobic biodegradability and to use the result as the fundamental data for sea food wastewater treatment. When the organic removal efficiency by chloride concentrations (1,400~18,000 mg/L) was evaluated, microbes adapted to the saline at ${\leq}$ 6,000 mg/L of chloride but treatment efficiency was not improved at ${\geq}$ 12,000 mg/L of chloride because of delayed reaction time. Functional coefficient $Y_I$ of non-biodegradable soluble organic and inert material production coefficient Yp by microbe metabolism increased as chloride concentrations increased. Soluble organic matter ratio by chloride concentration (0~18,000 mg/L) was 10.8~13.1%, inert material production efficiency by microbes metabolism was evaluated as 7.0~24.6%. $NH_3$-N removal efficiencies were 96.2, 96.5, 90.2 and 90.3% using original wastewater HRT 18 hr, 6,000 mg/L chloride concentration HRT 22 hr, 12,000 mg/L chloride concentration HRT 30 hr, and 18,000 mg/L chloride concentration HRT 45 hr, respectively. Nitrification process was more sensitive to salt concentration than organic matter removal to salt concentration. Under ${\geq}$ 6,000 mg/L chloride concentration, conversion rate from $NO_s$-N to $NO_2$-N was low.

• Journal of Korean Society on Water Environment
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• v.18 no.4
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• pp.365-370
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• 2002

This study aims to study the effect of HRT and influent concentration on swine wastewater treatment using UASB(Upflow Anaerobic Sludge Blanket). Sample was separately collected from the piggery farm; urine(liquid part) and solid part to compare their treatment characteristics. Reactors were used two UASB(3.2 L) in this research under constant temperature ($35^{\circ}C$). Their operating conditions were as follows; Run 1(UASB ; HRT 6-days, 1 cycle/d), Run 2(UASB ; HRT 3-days, 1 cycle/d). Biogas was collected and analyzed using GC(HP-6890). By comparing the results of Run 1 and Run 2, the effect of HRT was investigated. The treatment efficiency of Run 1 which had longer HRT was higher than that of Run 2 in both solid and liquid parts of piggery sample. Methane content in collected biogas is more than 80%.

• Journal of dental hygiene science
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• v.18 no.1
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• pp.9-17
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• 2018

The purpose of this study was to investigate the relationship between hormone replacement therapy (HRT) and periodontal disease in postmenopausal women using data from the 4th and 5th Korea National Health and Nutrition Examination Survey. A total of 5,482 postmenopausal women aged 45~75 years were included as study subjects in the final analysis. The HRT group comprised 1,035 postmenopausal women who had received HRT for at least one month, and the non-HRT group comprised 4,447 postmenopausal women who did not receive HRT. The chi-square test was used to confirm the bivariate relationship between the variables. Multinomial logistic regression analysis was used to adjust for covariance (age, education, family income, body mass index, age of menopause, alcohol, smoking, dental visit <1 per year, use of oral care products, and frequency of tooth brushing per day). After adjusting for all covariates, HRT was found to be associated with periodontal disease. In particular, the relationship between HRT and periodontal disease was more evident in older women and women younger than 45 years of menopausal age. The relationship between HRT and periodontal disease was stronger in women who brushed their teeth less than 3 times per day, women without regular oral examination, and women who did not use oral hygiene products. The results of this study confirmed the importance of actively considering hormone therapy when determining policy recommendations for postmenopausal women. Especially, health programs such as HRT, regular dental examination, and oral care are needed for older women who have undergone premature menopause.

• Journal of Ginseng Research
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• v.23 no.2 s.54
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• pp.99-104
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• 1999

The effects of ginseng and cinnamon extract alone or mixture on the various cancer cell lines in vitro have been examined. Human colon cancer cell line (HT-29), human rectal cancer cell line (HRT-18) and human hepatoma cell line (HepG2) were used for the experiment. When given separately, the proliferation of all cancer cell lines was inhibited in proportion to the concentration of ginseng or cinnamon extract, respectively. Based on the cytotoxic activity, mixture of ginseng and cinnamon extract demonstrated a synergistic inhibition of cancer cell growth. The progression of cell cycle from G1 to S phase was significantly inhibited by ginseng and cinnamon mixture in the HT-29 and HRT-18 cell lines.

• Preventive Nutrition and Food Science
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• v.5 no.1
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• pp.54-57
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• 2000

This study was designed to observe the anticancer activity of propolis on human rectal (HRT-18) and human colon (HCT-48) cancer cell lines in vitro, and on sarcoma-180 cells in vitro. The proliferation of HRT-18 and HCT-48 cancer cell lines was potently inhibited in proportion to the concentration of propolis. The survival time of the mice inoculated with sarcoma-180 cells was increased modestly by the administration of propolis compared to the control. Those observations suggest that propolis has anticancer effects against some of the cancer cell lines in vitro and in in vitro.

• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.279-284
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• 2013

In this study, the feasibility of a single-stage thermophilic aerobic process for the treatment of high-strength food wastewater produced from the recycling process of food wastes was examined to substitute anaerobic digestion process. Also, the removal and stability of thermophilic aerobic process were assessed according to the changes of hydraulic retention times (HRTs) and organic loading rates (OLRs). When the OLR increased from 9.2 to $37.2kgCOD/m^3d$, a pH value in R1 (HRT : 5 d) significantly decreased to 5.0, due to the organic acid accumulation. On the other hand, the pH value in R2 (HRT : 10 d) was stable and R2 showed the high removal of COD, organic acid and lipid, even though the OLR increased from 4.6 to $18.6kgCOD/m^3d$. In R1, the COD loading rates for COD removal was suddenly dropped, as the COD loading rate increased from 18.6 to $28.4kgCOD/m^3d$. In contrast, R2 showed that the COD loading rates for COD removal increased with regard to increment in the loading rates of 3.61, 7.05, 9.43 and $12.2kgCOD/m^3d$, indicative of the high COD removal efficiency. Therefore, the results demonstrated that over 10-d HRT, the high concentration of raw food wastewater was efficiently treated in the single-stage thermophilic aerobic process.