• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.743-750
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• 2008

In water treatment plant the Dissolved Ozone Flotation(DOF) System may be employed because this system has various abilities, such that it can remove SS using microbubbles, and it can exert strong oxidation power in removing taste and odor, color, and microbial agents. In order to investigate effectiveness of the DOF system in water treatment, removal characteristics of various water quality parameters were observed depending on the different levels of ozone concentrations. Removal efficiencies of water quality parameters in DOF system were compared with those in DAF(Dissolved Air Flotation) system and in CGS(Conventional Gravity Settling) system. Optimum ozone dose obtained in the pilot experiments was 2.7 mg/L. With increasing ozone dose higher than 2.7 mg/L, removal rates of turbidity, KMnO$_4$ consumption, UV$_{254}$ absorbance, and TOC were reversely lowered. High concentration of ozone dissociate organic matter in water, so that increasing dissolved organic level in effluent. Removal rates of water quality parameters at optimum ozone dose were obtained, such that removal rates of turbidity, KMnO$_4$ consumption, TOC, and UV$_{254}$ asorbance were 88.9%, 62.9%, 47%, and 77.3% respectively. Removal rate of THMFP was 51.6%. For all the parameters listed above, the DOF system was more effective than the DAF system or the CGS system. It is found that the DOF system may be used in advanced water treatment not only because the DOF system is more efficient in removing water quality parameters than the existing systems, but because the DOF system is also required smaller area than the CGS system for the treatment plant.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1123-1128
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• 2005

NIB(methylisoborneol) is an earthy/musty odor compound produced as a second metabolite by cyanobacteria and actinomycetes. MIB is not removed by conventional water treatment(coagulation, sedimentation, filtration) and its presence in tap water, even at low ng/L levels, can result in consumer complaints. PAC(powdered activated carbon) can effectively remove MIB when the correct dose is applied. But, since most operators in water treatment plants apply a PAC dose and then adjust that dose depending on direct observation (odor detection) after treatment, the result is often under-dose or eve,-dose. In this study, kinetic and isotherm tests using $^{14}C$-radiolabeled MIB were performed to determine coefficients for the HSDM(homogeneous surface diffusion model), including liquid film mass transfer coefficient($K_f$) and surface diffusion coefficient ($D_s$). The HSDM gave a reasonable fit and allowed prediction with the experimental data. Base on the HSDM, the authors developed an optimum PAC dose prediction program using the Excel spreadsheet. When the developed program was applied at two water treatment plants, the PAC dose based on the experience of operators in the water treatment plant was significantly different from that recommended by the newly developed program. If operators are willing to use the optimum PAC dose prediction program, it should solve dosing problems.

• Journal of Life Science
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• v.30 no.7
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• pp.598-605
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• 2020

Padina gymnospora is a brown algae of the class Phaeophyceae. It has been established that P. gymnospora ameliorates amyloid-β-induced neuropathology and has an anticoagulation effect, but this study was designed to estimate its skin-whitening effect and identify its active component. The ingredients of P. gymnospora were extracted with ethanol and its activity was compared with arbutin. First, the P. gymnospora extract was observed to inhibit tyrosinase activity in a dose-dependent manner, tyrosinase being the rate-limiting enzyme of melanin synthesis. Notably, where 200 μM of arbutin inhibited tyrosinase activity by 58.1%, P. gymnospora extract (0.5%) achieved 76.7%. The P. gymnospora extract also significantly reduced α-melanocyte-stimulating hormone-induced TRP-1 and TRP-2 mRNA expression. In addition, it significantly inhibited melanin synthesis in B16F10 melanoma cells. We identified the 0.66% fucosterol content that inhibited melanin synthesis as comparable to that of arbutin. Additionally, we tested the potential cytotoxicity of P. gymnospora by MTT and LDH release assay and found that the extract significantly reduced LDH release in CCD-986sk cells. These results indicate that P. gymnospora extract could be a potential active ingredient of cosmetics with a skin-whitening effect.

• Journal of Life Science
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• v.20 no.12
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• pp.1851-1858
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• 2010

Estrogen deficiency in peri- and postmenopausal women results in variety of neurovegetative, psychic and somatic symptoms, and may contribute to severe diseases within the aged female population. Ecklonia stolonifera (ES) is an edible brown algae traditionally used in fishery towns in Far East Asia. This study was performed to investigate the effects of ES extracts on blood flow and serum lipid concentration in ovariectomized rats. Weight-matched female Sprague-Dawley strain rats were assigned to four groups. Three groups were surgically ovariectomized (OVX). The fourth group was sham operated. Rats were randomly assigned to the following groups: sham-operated rats (Sham), ovariectomized control rats (OVX-CON), ovariectomized rats supplemented with ES extract at 50 mg/kg bw/day (OVX-ES50) and ovariectomized rats supplemented with ES extract at 200 mg/kg bw/day (OVX-ES200). Serum total cholesterol and triglyceride contents decreased in the sham group compared to the OVX-CON group. Six weeks feeding of ES extract resulted in a significant (p<0.05) lowering of serum triglyceride and a lowering tendency of total cholesterol level. The level of Hdl-cholesterol in serum increased by supplementation of ES extracts at 50 mg/kg and 200 mg/kg bw/day (p<0.05). Blood passage time of the ES extracts-supplemented group was higher than the OVX-CON group. The ability of platelet aggregation of groups treated with ES extracts was less than that of the OVX-CON group. These results suggest that the beneficial effects of ES extract may be used to possibly improve on the metabolic syndrome of menopausal women.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.706-712
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• 1999

PSD (particle size distribution) for 2,000 mg/$\ell$ natural loess in seawater showed normal distribution cure at 0 minute settling time, accompanying with very large particle distribution range with its mean particle diameter of 31.6 $\mu$m and coencient of variance of $72.6\%$, With elapsed time it showed that the PSD was rapidly changed from normal distribution cure to abnormal distribution curve, steepened the right-hand side of it and its coefficient of variance was getting increased because of rapid settling of large size particles, Cumulative weight distribution showed that 2,000 mg/$\ell$ natural loess in seawater was almost $100\%$ constituted of particles bigger than 20 $\mu$m in diameter. Ratio of $V_s/(D_{bm})^{1/2}$ for loess particles in seawater was increased with increase of particle size in geometrical progression. Almost all loess particles in seawater had Stokes settling velocity not less than 2,255 times of Brownian diffusion coefficient, There was almost to EDL (about 0.4 nm) around natural loess particles in seawater, Thus, there was always LVDW attractive force between loess particles approaching each other in seawater, and almost no EDL repulsive force. Loess particles were not always in the condition of easy floe formation. Concentration of natural loess in seawater increasing from 400 mg/$\ell$ to 10,000 mg/$\ell$, characteristics of the settling was changed from Type I settling (discrete settling) to Type II settling (flocculation settling). PVD (particle volume distribution) showed that natural loess particles in seawater were largely constituted of two types of particles, such as rapidly settling particles and suspended and dispersed particles for a long time. Amount of the latter was much less than that of the former.

• Korean Journal of Ecology and Environment
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• v.38 no.3 s.113
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• pp.372-381
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• 2005

This study was conducted to test the efficiency of water quality improvement using the dissolved air flotation (DAF) technique in a shallow eutrophic reservoir. The application of DAF was followed by the addition of a chemical coagulant (poly aluminum chloride; PAC). The experiment was conducted in the mesocosm scale (wide ${\times}$ length ${\times}$ depth: 6 m ${\times}$ 6 m ${\times}$ 3 m). Suspended solids (SS) and volatile SS (VSS) concentration decreased by 54 ${\sim}$ 71% and 57 ${\sim}$ 79% of the initial concentrations, respectively. Total phosphorus and Chl- a concentration also decreased by 74 ${\sim}$ 92% and 54 ${\sim}$ 98%, respectively. BOD decreased by>86% while COD decrease ranged 29 ${\sim}$ 63%. Dissolved inorganic P (DIP) and dissolved total P (DTP) concentration decreased by 34 ${\sim}$ 88% and 62 ${\sim}$ 88%, respectively. After DAF application further onto the sediment, DIP-release rates from the sediment decreased by 17% (0.82 ${\to}$ 0.68 mg $m^{-2}$$day^{-1}$ in the oxic condition and 23% (2.27 ${\to}$ 1.76 mg $m^{-2}$$day^{-1}$) in the anoxic condition, compared to the release rate from the untreated sediment. DTP-release rate from both the oxic and anoxic sediments also decreased by 33% (5.62 ${\to}$ 3.78 mg $m^{-2}$$day^{-1}$) and 20% (6.23 ${\to}$ 4.99 mg $m^{-2}$$day^{-1}$), respectively. These results suggest that the DAF application both to the water column and onto the sediment be effective to improve water quality by removing particulate matters in the water column as well as reducing P-release from the sediment.

• Journal of Acupuncture Research
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• v.29 no.1
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• pp.139-150
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• 2012

Objectives : The puropse of this study was to report the availability of Hyeongsang diagnosis compensating for visceral pattern identification in applying Sa-am acupuncture therapy. Methods : Eight cases was presented to substantiate the above. Results : According to the characteristic diagnostic method of Hyeongsang medicine by feature such as face, ears, eyes, nose and mouth shape, There are 8 pattern differentiations, including essence family, Qi family, spirit family, blood family, fish type, bird type, beast(running) type and crust(crustacea) type which are correlated with essence deficiency, heat harassing the heart spirit, Qi stagnation, blood stasis, kidney essence deficiency, intense heart fire, liver blood deficiency and lung Qi deficiency in the established visceral pattern identification, respectively. Eight patients was diagnosed by the above Hyeongsang 8 pattern differentiations, of whom Sinjeonggyeok(kidney reinforcing prescription) was applied to a patient with fish type and essence family to nourish kidney essence, and Giul prescription(Qi stagnation prescription) was given to a patient with Qi family for regulating Qi, and Sanghwa priscription(ministerial fire prescription) was delivered to a patient with Spirit family to clear the heart fire and tranquilize, and Sojangjeonggyeok(small intestine reinforcing prescription) was used for a patient with blood family to nourish blood and remove blood stasis, and Sinjeonggyeok(kidney reinforcing prescription), Simhangyeok(heart heat clearing prescription), Ganjeonggyeok(liver reinforcing prescription) and Pyejeonggyeok(lung reinforcing prescription) were utilized for fish type, bird type, beast(running) type and crust(crustacea) type respectively to reinforce the relevant visceral function. Conclusions : It was suggested that characteristic diagnostic method of Hyeongsang medicine should be helpful for enhancing the accuracy of the established visceral pattern identification, applying Sa-am acupuncture therapy more appropriately.