• Membrane Journal
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• v.18 no.3
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• pp.241-249
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• 2008

This study is to concentrate vanadium in Jeju groundwater using reverse osmosis processes, and to utilize the concentrate for vanadium water. Groundwater samples were taken from Wahyul, Ayum, and Seogwipo groundwater wells with different in vanadium content each other. Their vanadiuln concentrations were 31.8, 44.5, and 53.0 ppb, respectively. The rejection coefficients of every component in groundwater were increased with the increase of TMP At the TMP of $8 kg_f/cm^2$, the rejection coefficients of vanadium, sodium, potassium, aluminium, iron, and barium were $97.4%{\sim}99.0%,\;97.7%{\sim}97.8%,\;98.0%{\sim}98.3%,\;94.8%{\sim}97.5%,\;88.0%{\sim}96.4.0%$, and $97.9{\sim}98.0%$, respectively. And those of magnesium, calcium, chromium, mauganese, and strontium in three groundwater were more than 99.0% at the same TMP. It was possible that vanadium contents of Wahyul, Ayum and Seogwipo groundwater were concentrated into 58.6, 118.9, and 165.1 ppb, respectively, by 6 stages treatment at the recovery ratio of 15%. And these concentrated water (vanadium water) did not exceed the permissible drinking water standards.

• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.273-280
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• 1986

'Medicinal water' have been used for the treatment of disease and the promotion of health. To study the quality and health effect of 'medicinal water', the eleven springs located near Taegu City during the period of March 27-February 17, 1986 were tested for biological and physiochemical examination and were checked for sanitary environment around the spring. Among them three springs (27.3%) had a good sanitary equipments and only one was negative for biological examination. Three 'medicinal warer' were accepted as potable by physicochemical examination. According to above findings, all of the 'medicinal water' sampled from the springs located near Taegu City were not potable by this sanitary survey adopted Drinking Water Standard in Korea. Kachang and Youngchum 'medicinal water' were more contaminated by heavy metals and bacteria than those of other springs. To solve the problem of contamination by heavy metals that originated from uncertain sources, we should search for the sources of water contamination, remove it completely and also support the environmental equipments and management system in protection of safe 'medicinal water' supply.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.1
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• pp.1-6
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• 2012

Down Stream K River has high COD (4-10 mg/L) and high $NH_3$-N concentration (3.5 mg/L during winter period). Although $NH_3$-N itself is not reported harmful at this level, it must be removed to meet drinking water standard (0.5 mg/L). We constructed a pilot plant modifying the processes of conventional drinking water facilities. Prechlorination and powdered activated carbon (PAC) dechlorination was adopted prior to a flocculation tank to remove ammonia and prevent disinfection byproducts (DBPs) formation. Also, GAC processes was included after sand filter to remove residual DOC. This pilot having a capacity of 36 ton/day was operated for one year. The GAC processes were successful to remove ammonia and many organic pollutants (DOC, MBAS, UV-254 nm absorbance, etc). Influent DOC concentrations were very high as 3~6 mg/L throughout the plant operation. It was impossible to achieve 1.0 mg/L effluent DOC, indicating that bed depth (2 m) should be increased to achieve more strict DOC quality standards. When $Cl_2$ dose was well controlled ($Cl_2/NH_3$-N ratio 10~11 on a weight basis), $NH_3$-N removal was 98% and THMs was very low possibly due to low free residual chlorine and PAC dechlorination.

• Journal of Appropriate Technology
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• v.7 no.1
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• pp.72-81
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• 2021

Gravity-driven membrane (GDM) filtration system based on the nanofiber membrane was investigated. This system can be operated with little energy demand due to a gravitational pressure-driven filtration and biological fouling control strategy. Moreover, the optimal module configuration based on the high permeance of nanofiber membrane can provide a significantly high water productivity. In order to evaluate its applicability potential, the pilot-scale (3000-5000 L/day) systems with nanofiber membranes were operated in developing countries (Kiribati and Tuvalu). Our results showed that the 14-92 L/(m²×h) of the permeate flux was determined indicating a stabilized water productivity. In addition, the permeate water indicated a high removal rate (more than 99.99%) of turbidity and bacteria. Consequently, the system can provide a stabilized water production with safe permeate water quality during long-term operation. These findings exemplify an effective approach to decentralized drinking water treatment for developing countries.

• Korean Journal of Biological Psychiatry
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• v.3 no.2
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• pp.240-244
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• 1996

The effects of chronic treatment with haloperidol on the binding capacities of dopamine(DA) $D_2$-like receptor were investigated in rat striatum and olfactory tubercle. The authors tried to confirm the dose-response effects with usual dose and low dose haloperidol. Rats were treated with haloperidol(0.05, 0.15, 0.5, 1.5mg/kg/day in drinking water) for four weeks. Saturation analysis of the binding of [$^3H$]spiperone to striatal membranes showed that the haloperidol treatment(0.05, 0.5, 1.5mg/kg) induced significant proliferation. The changes of dissociation constant(Kd) were not significant in striatum. The maximal binding density(Bmax) and Kd increased remarkably following the treatment with usual dose haloperidol (1.5mg/kg) in olfactory tubercle. Although there was increasing trend other the treatment with low dose haloperidol, the change of Bmax was not significant statistically. The present findings indicate that low dose haloperidol induces the proliferation of DA $D_2$-like receptor in striatum and interact with the dopaminergic transmission which might underlie the antipsychotic effect. This finding may support the recent clinical suggestion on the low dose strategy in the treatment of schizophrenia.

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.946-953
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• 2002

Bisphenol A [2, 2 bis (4-hydoxyphenyl) propane; BPA] is a widely used endocrine disruptors and has estrogenic: activities. Although interests on biological effect of BPA are rising, evidences of its effect on immune system are lacking. We investigated that the effect of BPA on immune parameters to postulate the mechanism, and BPA interruptions between neuroendocrine and immune system. BPA was administrated to mice by p.o. (as a drinking water) dose on 0.015, 1.5 and 30 mg/ml for 4 weeks. The BPA treatment did not result in any change in body weight, spleen weight and distribution of lymphocyte subpopulation collected from spleen. BPA induced prolactin production in spleen, and exposure of SPA increased the activity of splenocyte proliferation in response to Con A (p<0.001). The production of a strong Th-1 type cytokine ($IFN-{\gamma}$) was induced while Th-2 type (IL-4) was suppressed by SPA treatment. These were consistent with RT-PCR results of transcription factor GATA-3 and IRF-1. These findings suggested that stimulation of prolactin production by estrogenic effects of SPA would affect cytokine profiles, and lead to imbalanced cellular immune response. In addition, we could speculate that prolactin and cytokine is important mediator involved in network between neuroendocrine and immune system by BPA.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.398-404
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• 2005

Radioprotection is of practical importance for the normal tissues of tumor patients subject to radiotherapy, people with planned or accidental exposure to radiation, and the public and radiation workers. Since oxygen enhances radiation - induced biological damage, antioxidants should be related with the function as a radioprotectors. Ascorbic acid or caffeine is an essential component and antioxidant in the diet of humans and a small range of other mammals. The present study investigates functional radioprotection of caffeine and ascorbic acid against gamma radiation in irradiated C57BL/6N mice. Eight-week-old male C57BL/6N mice were irradiated with 6.5 Gy. A caffeine treated group was administered with $80mg\;kg^{-1}$ body weight by intraperitoneal injection, a single treatment 1 hr before irradiation. Ascorbic acid was administered $330\;mg\;L^{-1}$ in drinking water through all the experimental period. According to time schedules, animals were sacrificed by cervical dislocation. And the samples were collected 2 weeks after whole- body gamma irradiation. The caffeine treated group showed lower decrement of body and organ weights than the other experimental groups. The qualitative analysis of circulating testosterone in serum was performed by means of radioimmunoassay (RIA). The normal level of circulating testosterone was maintained by the treatment of caffeine and ascorbic acid. The change of weight of body and organ and the appearance of seminiferous tubules were improved by an effect of caffeine or ascorbic acid against irradiation. Taken together, caffeine and ascorbic acid protects impairment of spermatogenesis against gamma radiation and may act as a radio-protector.

• Journal of Soil and Groundwater Environment
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• v.19 no.4
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• pp.62-69
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• 2014

In the results of monitoring nitrate concentration in more than 8,000 groundwater wells around agro-livestock, the average and maximum nitrate concentration was 9.4 mg/L and 101.2 mg/L, respectively. Since about 31% of the monitoring wells was exceed the quality standard for drinking water, nitrate control such as remediation or source regulation is required to conserve safe-groundwater in South Korea. Typical nitrate-treatment technologies include ion exchange, reverse osmosis, and biological denitrification. Among the treatment methods, biological denitrification by indigenous microorganism has environmental and economic advantages for the complete elimination of nitrate because of lower operating costs compared to other methods. Major mechanism of the process is microbial reduction of nitrate to nitrite and nitrogen gas. Three functional genes (nosZ, nirK, nirS) that encode for the enzyme involved in the pathway. In this work, we tried to develop simple process to determine possibility of natural denitrification reaction by monitoring the functional gene. For the work, the functional genes in nitrate-contaminated groundwater were monitored by using PCR with specific target primers. In the result, functional genes (nosZ and nirK) encoding denitrification enzymes were detected in the groundwater samples. This method can help to determine the possibility of natural-nitrate degradation in target groundwater wells without multiplex experimental process. In addition, for field-remediation application we selected nitrate-contaminated site where 200~600 mg/L of nitrate is continuously detected. To determine the possibility of nitrate-degradation by stimulated-natural attenuation, groundwater was sampled in two different wells of the site and nitrate concentration of the samples was 300 mg/L and 616 mg/L, respectively. Fumarate for different C/N ratio was added into microcosm bottles containing the groundwater to examine denitrification rate depending on carbon concentration. In the result, once 1.5 times more than amount of fumarate stoichiometry required was added, the 616 mg/L of nitrate and 300 mg/L of nitrate were completely degraded in 8 days and 30 days. The nitrite, byproduct of denitrification process, was also completely degraded during the experimental period.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.271-283
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• 2006

A systematic water quality survey was conducted in August, 2005 for a drinking water supply reservoir (the Jeolgol reseuoir located in an island), which is at an early stage of impoundment, to investigate the causes of water color deterioration of the reservoir and the clogging of filter beds of a water treatment plant. The reservoir shape was simple and its average depth was 5.5 m, increasing from upreservoir toward the downreservoir end near the dam. Dissolved oxygen (DO) and chloropllyll-a (chi-a) showed a large variation while water temperature had a smaller range. Transparency ranged from 0.6 to 0.9 m (average 0.7 m). The average value of turbidity was 9.3 NTU, ranging from 8.0 ${\sim}$ 12.1 NTU. The transparency and the turbidity appear to be affected by a combination of biological and non-biological factors. The poor transparency was explained by an increase of inorganic colloids and algal bloom in the reservoir. The blockage of the filter bed was attributed to the oversupply of phytoplanktons from the reservoir. The range and the average concentration of chi-a within the reservoir were 31.6 ${\sim}$ 258.9 ${\mu}g\;L^{-1}$, 123.6 ${\mu}g\;L^{-1}$ for the upper layer, and 17.0 ${\sim}$ 37.4 ${\mu}g\;L^{-1}$, 26.5 ${\mu}g\;L^{-1}$ for the bottom layer, respectively. A predominant species contributing the algal bloom was Dinophyceae, Peridinium bipes f. occultatum. The distribution of Peridinium spp. was correlated with chi-a concentrations. The standing crop of phytoplankton was highest in the upreservoir with $8.5\;{\times}\;103\;cells\;mL^{-1}$ and it decreased toward the downresevoir. Synedra of Bacillariophyceae and Microcystis aeruginosa of Cyanophyceae appeared to contribute to the algal bloom, although they are not dominated. It is mostly likely that sloped farmlands located in the watershed of the reservoir caused water quality problems because they may contain a significant amount of the nutrients originated from fertilizers. In addition, the aerators installed in the reservoir and a shortage of the inflowing water may be related to the poor water quality. A long-term monitoring and an integrated management plan for the water quality of the watersheds and the reservoir may be required to improve the water quality of the reservoir.

• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.347-355
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• 2008

Perfluorooctanoic acid (PFOA), a member of the perfluoroalkyl acids that have wide commercial applications, is persistent organic pollutants widely spread throughout the environment and human population. But little is known about the adverse biological effects of the PFOA. In the present study, the toxicological effects of PFOA were investigated in rats. Sprague-Dawley rats (N = 10 in each group) were orally administered with PFOA in drinking water for 4 weeks (0, 100, 200, or 400 ppm in male, and 0, 200, 400, or 800 ppm in female). Three female rats given 800 ppm died during the study. PFOA treatment decreased the body weight gain and increased the liver weights in both genders. Serum biochemical investigations revealed significant increases in the aspartate aminotransferase, alanine transaminase, alkaline phosphatase, blood urea nitrogen, total cholesterol, and total bilirubin in male but in female. Serum estradiol (E2) levels were increased in all treated rats. Histopathologically, hepatocellular hypertrophy around central vein was noted in the liver of treated rats. No significant histopathological changes were noted in other organs. In conclusion, PFOA induced toxicological changes in the liver and increased serum E2 level which was not related to histopathological changes of endocrine and reproductive system.