• The KSFM Journal of Fluid Machinery
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• v.17 no.3
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• pp.41-45
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• 2014

The biological aerated filter (BAF) reactor is regarded as an effective biological wastewater treatment method. It can remove pollutants by carrier filtration and biodegradation. Due to its advantages, which include high biomass retention, tolerance to toxicity, excellent removal efficiency, and slurry separation, BAF has been widely used to remove COD, $NH_4{^+}-N$, phosphorus, and other harmful organic substances. In this study, the BAF reactor was used to remove organic contaminants of domestic wastewater of Korea at both the benchand pilot-scale. The main objectives of this study are to: (i) investigate the removal efficiency of organic contaminants (ex. COD, nitrate, phosphorus) in BAF reactors at both scales; (ii) characterize the small-scale wastewater treatment plant using the BAF reactor. The concentration of COD in the influent increased from 69 to 246 mg/L. During the operation period, the final effluent concentration of COD remained maximum 4.0 mg/L, and the average removal efficiency was above 88%. The present study investigated the removal efficiencies of COD, TN, TP and $NH_4{^+}-N$ from smelting wastewater by BAF system. When treating wastewater in both bench and pilot-scale reactors, the BAF worked well.

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1493-1498
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• 2016

The efficiencies of Gang-Byeon sewage treatment facilities, which are based on GPS-X modelling, were analysed and used to design recycle water treatment processes. The effluent of an aeration tank contained total kjeldahl nitrogen (TKN) of 1.8 mg/L with both C-1 and C-2 conditions, confirming that most ammonia nitrogen ($NH_3{^+}-N$) was converted to nitrate nitrogen ($NO_3{^-}-N$). The concentrations of $NH_3{^+}-N$ and $NO_3{^-}-N$ were found to be 222.5 and 227.2 mg/L, respectively, with C-1 conditions and 212.2 and 80.4 mg/L with C-2 conditions. Although C-2 conditions with higher organic matter yielded a slightly higher nitrogen removal efficiency, sufficient denitrification was not observed to meet the discharge standards. For the total nitrogen (T-N) removal efficiency, the final effluent concentrations of T-N were 293.8 mg/L with biochemical oxygen demand (BOD) of 2,500 mg/L, being about 1.5 times lower than that (445.3 mg/L) with BOD of 2,000 mg/L. Therefore, an external carbon source to increase the C/N ratio was required to get sufficient denitrification. During the winter period with temperature less than $10^{\circ}C$, the denitrification efficiency was dropped rapidly even with a high TKN concentration (1,500 mg/L). This indicates that unit reactors (anoxic/aerobic tanks) for winter need to be installed to increase the hydraulic retention time. Thus, to enhance nitrification and denitrification efficiencies, flexible operations with seasons are recommended for nitrification/anoxic/denitrification tanks.

• The Journal of Pediatrics of Korean Medicine
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• v.30 no.4
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• pp.99-110
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• 2016

Introduction Jaundice is one of the most common conditions found in neonatal period. Phototherapy is one of the main treatments for neonatal jaundice. However, several adverse effects of the phototherapy have been reported, including DNA damage recently. Therefore, a variety of treatments have been conducted to shorten the duration of phototherapy. Meanwhile, it has been hardly tried to prevent neonatal jaundice, but diverse approaches have been tried in traditional Chinese medicine (TCM) for many years. Therefore, this study aims to analyze the studies for the treatments to prevent neonatal jaundice based on TCM. Materials and Methods Various literatures have been searched via CNKI, and PubMed using the terms "neonatal jaundice" (新生儿黄疸, 胎黃, 胎疸) in category of 'Traditional Chinese Medicine', 'Traditional Chinese Medicinal Herbs' and 'Combination of Traditional Chinese Medicine With Western Medicine'. The search range included randomized controlled trials (RCTs), controlled clinical trials (CCTs), case reports, reviews and animal experiments published from 2013 to 2015. Results A total of 104 studies were found. 93 articles were excluded by reviewing the titles and abstracts. Out of the remaining 11 studies, 9 articles were RCTs, 2 articles were CCTs. The treatment used in neonatal babies in the studies were, using herbal remedies (meditation 5, bath 3 and retention enema 1) and the acupressure. All treatments were initiated within the first 24-48 hours after their birth. Then, there was a study that the subjects taken the herbal medicine were women during pregnancy. The outcome assessments used were the serum total bilirubin (TB), transcutaneous bilirubin measurement (TCB), the incidence of the hyperbilirubinemia, the duration time of the jaundice. Especially, TB, TCB and the incidence of the hyperbilirubinemia have decreased significantly more than that of the control group in the most of the results. No severe adverse events were reported in all articles reviewed. Conclusions Conventional treatment such as, herbal medicine in TCM, seems to be the effective way to prevent neonatal jaundice or hyperbilirubinemia. Therefore, the conventional treatment may be favorable choice for preventive treatment for neonatal jaundice.

• Food Science and Preservation
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• v.8 no.1
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• pp.23-29
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• 2001

To extend the freshness of late autumn Chinese cabbage, the packaging and loading effects on the quality were investigated during cold storage. Judging from overall quality during storage period, late autumn Chinese cabbage could be stored by 3 months at 0$\^{C}$ cold storage. However, late autumn Chinese cabbage was not acceptable for long-term storage because of its marketability and the storage cost. Among 3 packaging methods(PP-net, carton and plastic container) for stored Chinese cabbage, plastic container and carton were more effective than PP-net packaging for the freshness prolongation. Gas composition in the plastic bags during storage was not significantly different among packaging conditions and O$_2$ and CO$_2$ concentrations were 13∼18% and 0.75∼7.48%, respectively, MAP with plastic film was effective for the quality retention because of low oxygen composition and high humidity condition in the bags.

• The Journal of the Korean dental association
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• v.47 no.9
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• pp.585-595
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• 2009

Purpose : The aim of this study was to compare surgical complications between simple implant placement and implant placement combined with complicated surgical procedures. We also evaluated prosthetic complications according to the specific types of prosthesis. Material and Method : A retrospective analysis of dental chart of patients who was performed implant therapy during the period from June 2003 to December 2005 was carried out. This study was performed on 408 patients (208 male, 200 female). In addition, 1671 implants were performed. Based on their medical record and radiographs, the authors evaluated surgical and prosthetic complications, surgical procedures accompanied at the time of implant, risk factors of implant failure etc. Result : Surgical complications were developed on 358 implants(21.4% on total placed implants) and wound dehiscence was most prevalent complication. On maxillary posterior area, surgical complications developed more frequently on implants with major surgery and showed a significant difference. And complication rate of implants accompanied with GBR was higher than that of simple implants placement and also showed significant difference. The implant supported prosthesis showed no statistical difference in the occurrence of complications according to the types of prosthesis, and food retention was the most common post-prosthetic complication. Also we speculated that length and width of implant showed significant correlation to the failure of implant primary osseointegration. Conclusion : Based on the result, clinician should provide more careful maintenance for patients with implant placement accompanied by complicated surgical procedure. And periodic maintenance for the patient is requested for long-term survival of implant therapy.

• The Journal of the Korean dental association
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• v.54 no.12
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• pp.1024-1034
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• 2016

Purpose. The purpose of this study was to compare the type and frequency of prosthetic complications associated with attachment types for implant overdenture. Material and methods. In this retrospective study, 38 patients (mean age, 63.5 years) have been treated with implant overdentures from 2007 to 2014. Ten patients received a bar-clip attachment. Eleven patients had received a milled bar with Locator attachment. Seventeen patients had received a Locator attachment. The mean follow-up period was 36.9 months (range, 15-83 months). The type and frequency of prosthetic complications was recorded. The frequency was analyzed to determine the statistical difference among the 3 different attachments by using one-way ANOVA (${\alpha}=.05$) and Bonferroni post hoc method at a 5% level of significance. Results. The total number of prosthetic complications was higher in the bar-clip attachment (55 events) than in the milled bar with Locator attachment (39 events) and the Locator attachment (34 events). There were no statistically significant differences, and the most common prosthetic complication was the loss of retention. In the bar-clip attachment group, the average frequency of prosthetic complications was 3.0 events per prosthesis during the first year. In the milled bar with Locator attachment and Locator attachment groups, the average frequencies were 1.45 events and 2.35 events, respectively. Statistically significant differences were observed in the frequency of the complication. (p = .043) Conclusions. Compared to the bar-clip attachment, implant overdentures that use milled bars with the Locator attachment have a significantly lower incidence of prosthetic complications in the first year of follow-up after placement.

• Journal of Environmental Health Sciences
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• v.36 no.4
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• pp.323-336
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• 2010

We evaluated the properties of a fixed-bed column reactor for high-concentration tetrachloroethylene (PCE) removal. The anaerobic bacterium Clostridium bifermentans DPH-1 was able to dechlorinate PCE to cis-1,2-dichloroethylene (cDCE) via trichloroethylene (TCE) at high rates in the monoculture biofilm of an upflow fixed-bed column reactor. The first-order reaction rate of C. bifermentans DPH-1 was relatively high at $0.006\;mg\;protein^{-1}{\cdot}l{\cdot}h^{-1}$, and comparable to rates obtained by others. When we gradually raised the influent PCE concentration from $30\;{\mu}M$ to $905\;{\mu}M$, the degree of PCE dechlorination rose to over 99% during the operation period of 2,000 h. In order to maintain efficiency of transformation of PCE in this reactor system, more than 6 h hydraulic retention time (HRT) is required. The maximum volumetric dechlorination rate of PCE was determined to be $1,100\;{\mu}mol{\cdot}d^{-1}l$ of reactor $volume^{-1}$, which is relatively high compared to rates reported previously. The results of this study indicate that the PCE removal performance of this fixed-bed reactor immobilized mono-culture is comparable to that of a fixed-bed reactor mixture culture system. Furthermore, our system has the major advantage of a rapid (5 days) start-up time for the reactor. The flow characteristics of this reactor are intermediate between those of the plug-flow and complete-mix systems. Biotransformation of PCE into innocuous compounds is desirable; however, unfortunately cDCE, which is itself toxic, was the main product of PCE dechlorination in this reactor system. In order to establish a system for complete detoxification of PCE, co-immobilization of C. bifermentans DPH-1 with other bacteria that degrade cDCE aerobically or anaerobically to ethene or ethane may be effective.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.1
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• pp.71-84
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• 2007

Statement of problem: Implant surface characteristics plays an important role in clinical success and many studies have been made for improvement of success by changing surface roughness. Purpose: Appropriate increase of surface roughness increases the activity of osteoblast and enhance contact and retention between bone and implant. Material and method- Machined, SLA and RBM surface implants, which are the most commonly used implants were implanted into the tibia of rabbits and after 1 week, 4 weeks, 8 weeks and 12 weeks there were histologic and histomorphometric analysis and study for bone gradient and change of Ca/P ratio using EDS(Energy Dispersive X-ray Spectroscope). Results: Comparison of bone-implant contact showed no significant difference among each implant. In comparison of bone area rates, SLA showed higher value with significant difference at 1 week and 4 weeks, and SLA and RBM at 8 weeks than Machined implant (p<0.05). In analysis of bone constituents with EDS, titanium was specifically detected in new bones and the rates were constant by surface treatment method or period. In case of Ca/P ratio, according to surface treatment method, each group showed significant difference. Lots of old bone fragments produced during implantation remained on the rough surface of RBM implant surface and each group showed histological finding with active synthesis of collagen fibers until 12 weeks. In transmission electronic microscopic examination of sample slice after elapse of twelve weeks, tens nm of borderline (lamina limitans like dense line)was seen to contact the bone, on the interface between bone and implant. Conclusion: SLA and RBM implant with rough surface shows better histomorphometrical result and the trend of prolonged bone formation and maturation in comparison with Machined implant. In addition, implant with rough surface seems to be helpful in early stage bone formation due to remaining of old bone fragments produced in implantation. From the results above, it is considered to be better to use implant with rough surface in implantation.

• The Journal of Korean Medicine
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• v.24 no.2
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• pp.32-39
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• 2003

Objectives : In Oriental Medicine, hyperlipidemia is considered as phlegm retention (痰飮) and blood stasis (瘀血). Typhae pollen helps remove blood stasis and hemorrhage, and it also has an effect of relieving pain caused by blood stasis. The purpose of this study is to investigate the preventive effects of Typhae pollen on diet-induced hyperlipidemia in rats. Methods : Thirty-two male Sprague-Dawley rats were divided into normal, control and treated groups. The control and treated groups were fed with a 1.5% cholesterol diet over 4 weeks, and extract of Typhae pollen was administered to the treated group during the same period. Blood samples were collected from each animal at 0 and 4 weeks and used for the blood chemical analysis. Animals were sacrificed at 4 weeks and chemical analysis was performed on the collected liver samples. Results : The serum total cholesterol ($122.45{\pm}4.96mg/dL$), LDL-cholesterol ($54.27{\pm}4.95mg/dL$), and triglyceride ($122.00{\pm}7.33mg/dL$) values of the treated group were significantly lower compared with the serum total cholesterol ($147.91{\pm}7.22mg/dL$), LDL-cholesterol ($81.91{\pm}8.34mg/dL$), and triglyceride ($169.27{\pm}12.34mg/dL$) values of the control group. The liver total cholesterol (TEX>$230.18<{\pm}18.81mg/dL$) values of the treated group were significantly higher compared with the liver total cholesterol ($178.54{\pm}$10.11mg/dL) values of the control group. Conclusions : On the basis of these results, it is confirmed that Typhae pollen has preventive effects on diet-induced hyperlipidemia in rats.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.19-25
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• 2006

The effect of vitamin E supplementation on plasma ${\alpha}$-tocopherol level, total antioxidant level and reproductive performance in Murrah buffaloes was studied during periparturient period. Twenty-four advance pregnant buffaloes were randomly divided into four equal groups as $T_1$, $T_2$, $T_3$ and $T_4$ and were supplemented with 0, 1,000, 1,500 and 2,000 IU of ${\alpha}$-tocopheryl acetate (Merck) from 60 days prepartum to 30 days postpartum and 0, 500, 750 and 1,000 IU from 30 to 60 days postpartum, respectively. Blood samples were collected at -60, -45, -30, -15, -7, 0, 7, 15, 30 and 60 days of parturition and were analyzed for plasma ${\alpha}$-tocopherol and total antioxidant activity (TAA). The intake of DM, CP and TDN did not vary among different groups. Plasma ${\alpha}$-tocopherol and TAA around parturition (-7 to 15 day) in $T_3$ and $T_4$ were significantly higher than the control group. There was 17% reduction in retention of fetal membranes (RFM) and metritis in $T_4$ than control. The post partum estrus interval averaged 58.00, 55.33, 51.83 and 43.00 days in $T_1$, $T_2$, $T_3$ and $T_4$ respectively. There was significant reduction in days open in both $T_3$ and $T_4$ in comparison to $T_1$ group (127,130 Vs.146). All the vitamin E supplemented groups showed reduction in days open than their previous lactation performance. Supplementation of vitamin E at $1,500IU\;d^{-1}$ from 60 day prepartum to 30 day post partum to buffaloes exhibited beneficial effect on plasma ${\alpha}$-tocopherol level and TAA around parturition and continuation of its supplementation at $1,000IU\;d^{-1}$ from 30 to 60 days of lactation improved post partum reproductive performance of buffaloes.