• Geophysics and Geophysical Exploration
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• v.2 no.2
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• pp.96-103
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• 1999

Most of saline water inousions have been diagnosed by geophysical or geochemical approach independently. The objective of this study is to provide the effective method to detect the saline water intrusion on the ground water in the vicinity of seashore using these two methods. Schulumberger sounding, frequency domain electromagnetic sounding and geochemical analysis of ground water were carried out to explore saline water intrusion. Schulumberger sounding was implemented in dry surface condition before irrigation water was introduced into the field, while electromagnetic sounding was carried out in wet ground condition after the irrigation. The purpose of duplicated measurements on the equivalent spot at different times was to investigate the variation of anomaly zone depending on the amount of ground water. It was possible to discriminate the anomalous zone due to high water saturation from the low electric resistivity zone by high salt concentrations through this way. For the verification of the geophysical result, the ground water samples in the study area were collected and analysed at the 23 points near the measuring spots. The groundwater at the spot nearest to the sea water intrusion identified by geophysical method indicates higher salinity than the standard limit concentration for agricultural irrigation water (250 mg/1). Isotope analysis of $D({^2}H)$ vs. is ${^18}O$ and PCA analysis were used to discriminate the anthropogenic pollution from those of high salinity from sea water intrusion.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.287-296
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• 2008

A comprehensive quality survey for heavy metals, organophosphorous and organochlorine residual pesticides, and coplanar PCBs in samples such as water, sediments and soils as well as spiders has been implemented. The samples were undertaken at nine stream sites and their vicinity in August 2006, representing different surrounding environments. The levels of PCBs were expressed as concentrations and WHO-TEFs. Among 12 coplanar PCBs as target compounds in this study, 2,3', 4,4', 5-PentaCB (IUPAC # 118) was the congener with the highest concentration. The total concentrations and TEF values of coplanar PCBs in Siheung stream sediment (heavy industrial complex site located in Ansan city) were 3915.50 pg/g and 0.8366 pg-TEQ/g on a dry weight basis, respectively. Such levels were around 40 times higher compared to sediment from Gapyung stream (green site located in the upper of Myunggi mountain). It is probably due to the direct input of PCBs trom PCBs treatment materials. Organophosphorous (EPN, dementon-s-methyl, diazinon, parathion, and phenthoate) and organochlorine (alpha-BHC, aldrin, 4,4'-DDT, 4,4'-DDE, endosulfan alpha and etc.) pesticides were not detected above 5 ppb of detection limits. The concentrations of Cu and Cd in water and sediment samples from Siheung stream were 44.11 and $0.17ug/m\ell$ and $713.42{\mu}g/g$ and $3.73{\mu}g/g$, respectively, which contained $20\sim40$ times higher concentrations than those from Gapyung stream. In addition to the water and sediment samples, the levels of heavy metals in spider from designated sampling sites were also determined. Heavy metals in spider collected near Siheung stream was appeared to be equivalent and/or a little higher levels with respect to other spiders. Furthermore, the ratio of relative heavy metals (Cu, Cd, and Pb) in spider from each stream site showed a correlation as similar as that of heavy metals in soil samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1095-1100
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• 2008

Antioxidative and macrophage phagocytic activities and contents of functional component in selected Korean chestnuts (Dantaek, Daebo, Okkwang, Seokchu, Byunggo) were evaluated. Coumarin, gallic acid and catechin in inner skin and whole kernel of selected Korean chestnuts were detected by HPLC. The predominant functional components in inner skin of chestnut were catechin, followed by gallic acid and coumarin. However, the whole kernel had only gallic acid. Thus, the antioxidant properties of gallic acid and catechin were evaluated through DPPH radical-scavenging activity and SOD like activity. Gallic acid and catechin at 6.0 mg/100 g exhibited 69.4% and 38.3% of scavenging activities on DPPH radical, respectively. DPPH radical-scavenging activity of gallic acid increased in a concentration-dependent manner. Gallic acid was found to possess higher DPPH radical-scavenging activity than equivalent amount of catechin at all concentrations, whereas catechin was found to have higher SOD like activity than gallic acid. In addition, pre-incubation of macrophage with white kernel extract from Byunggo resulted in a significant increase of phagocytic activity and yellow kernel extracts from Byunggo, Dantaek, Daebo and Okkwang, leading to an increase in phagocytic activity compared with untreated cells. Yellow kernel extracts was found to have higher phagocytic activity than white kernel extracts. Byunggo had the highest phagocytic activity. The results suggest that the Korean chestnut may provide a natural source of antioxidants and active immunity.

• Journal of Life Science
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• v.20 no.10
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• pp.1476-1482
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• 2010

The purpose of the present investigation was to evaluate the effects of swimming training on response of lipid peroxide (MDA) and superoxide dismutase (SOD) enzyme activity of hyperlipidemic rats. Twenty-five male SD rats (6 weeks old) were randomly divided into a control group and 4 swimming groups after hyperlipidemia induction for 4 weeks through a 1% cholesterol diet. Swimming groups were then divided into unloaded swimming group, low-loaded swimming group, moderate-loaded swimming group and high-loaded swimming group by swimming intensity, and made to swim for 6 weeks (6 days/week). The loaded swimming group rats among the swimming groups swam a lead weight equivalent to 0%, 3%, 5% and 7% of body weight attached to the base of the tail. All data were expressed as mean and standard deviation by using an SPSS/$PC^+$ program, and to evaluate the differences between groups, data were analyzed by one-way analysis of variance and Duncan multiple range test (${\alpha}$=0.05) was performed to test the significant levels of differences between groups. The conclusions obtained from this study were as follows: 1) all swimming groups had significantly lower levels of MDA than the control group (p<0.001). Among the swimming groups, the moderate-loaded group had a significantly lower level than the unloaded group, low-loaded group and high-loaded group (p<0.001). 2) all swimming groups had significantly higher levels of SOD than the control group (p<0.01). Among swimming groups, the unloaded group, moderate-loaded group and high-loaded group had significantly higher levels than the low-loaded group (p<0.01).

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.57-61
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• 1992

For testing salts effect on seed germination, nitrogen solutions($(NH_4)_2SO_4$, $NH_4NO_3$, $KNO_3$, $Mg(NO_3)_2$, $Ca(NO_3)_2$, $(NH_2)_2CO$) were treated to chinese cabbage(Brassica rape L.) and lettuce(Lactuca sativa L.) seeding on the quartz sand bed given a tilt to wet by dripping. Electrical conductivities (mS/cm) increased with direct proportion by equivalent gram-molecular weight at $(NH_4)_2SO_4$ and $KNO_3$, $NH_4NO_3$, but those of Mg and Ca salt remained 1 1/2 times higher. And urea solution never showed EC at all. $(NH_4)_2SO_4$ solution appeared to have value of EC with 1.37 times as high as that of $KNO_3$ and it was in order of $(NH_4)_2SO_4>NH_4NO_3>KNO_3>Ca(NO_3)_2>Mg(NO_3)_2$ comparing with same percentage solution. Application of $Mg(NO_3)_2$ and $(NH_4)_2SO_4$ among 6 salts resulted in a severe decreas in germination of both crops, and $NH_4NO_3$ showed light inhibition in comparison to $KNO_3$. Urea showed little effect on germination as the same as $Ca(NO_3)_2$ and $KNO_3$ solution at low concentrations, but the latter two salts reduced germination remarkably at high concentrations. It is likely to show that germination inhibition is not affected by salt salanity but by the sort of salts.

• Journal of Radiation Protection and Research
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• v.24 no.2
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• pp.65-72
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• 1999

A methodology for determining the optimal durations of the use of contaminated crops as feedstuffs of cattle was designed based on the cost-benefit analysis method. The results of application for pigs, an omnivorous cattle, were discussed for the hypothetical deposition of radionuclides on August 15 when a number of crops are fully developed in Korean agricultural conditions. For investigating the relative cost-effectiveness of the use of contaminated crops as feedstuffs, the net benefit was compared with the case of the direct disposal of contaminated crops. The time-dependent radionuclide concentration in crops after the deposition was predicted using a dynamic food chain model DYNACON. The net benefit from the actions was quantitatively evaluated in terms of cost equivalent of doses and monetary costs of implementing the action. It depended on a number of factors such as radionuclides, variety of crops supplied as feedstuffs and duration of the actions. The use of contaminated crops as feedstuffs was more cost effective for $^{90}Sr\;or\;^{131}I$ deposition than for $^{137}Cs$ deposition.

• The Korean Journal of Pain
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• v.9 no.1
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• pp.75-82
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• 1996

Background: Nerve blocks, including epidural analgesia, can be risky for terminal cancer pain patients in generally poor conditions. We performed this study to evaluate the efficacy of intravenous patient-controlled analgesia(PCA) to treat severe pain of terminally ill cancer patients during the last days of life. Methods: We explained the patient's poor general condition to relatives and received a written consent to administer PCA. The starting dose of opioid for PCA in cancer pain management was based on previous 24-hour dose. Previous 24-hour opioid dose was converted to intramuscular morphine equivalent. The concentration of opioid mixed into Basal Bolus $Infusor^{(R)}$ was controlled to allow for one half of the previous 24-hour equianalgesic dose to infuse continuously. Patients controlled their pain by pushing the PCA module themselves. Patients were observed by pain service team. Some discharged patients were treated at home until death. Results: Forty eight patients received PCA for last two years. The most common reason receiving a PCA was the patient's poor general condition(52.0%). The mean starting dose of PCA was $20.6{\pm}16.2$ mg of morphine. Over eighty percents of the patients were in good or tolerable state of analgesia. Half of the patients expired within one week. The mean duration of PCA was $8.7{\pm}7.0$ days. The problems during PCA were: difficulty in maintaining intravenous routes, early loss of mentality after starting PCA, hypotension and nausea. Conclusion: We concluded that PCA, if correctly, is an effective, relatively safe and readily controllable method of pain management in terminally ill cancer patients during the last days of life. For future considerations, terminal patients may expire at the comfort of their own homes after the resolution of legal problems regarding using opioid in home care.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.3
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• pp.211-220
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• 2020

When domestic sewage and rainwater runoff are discharged into a single sewer pipe, it is called a "combined sewer system." The sewage design standards in Korea specify the flow velocity based only on the volume of rainfall; therefore, sedimentation occurs on non-rainy days owing to the reduced flow rate and velocity. This sedimentation reduces the discharge capacity, causes unpleasant odors, and exacerbates the problem of combined sewer overflow concentration. To address this problem, the amount of sewage on non-rainy days, not just the volume of rainfall, should also be considered. There are various theories on sedimentation in sewer movement. This study introduces a self-cleansing velocity based on tractive force theory. By applying a self-cleansing velocity equivalent to the critical shear stress of a sand particle, sedimentation can be reduced on non-rainy days. The amount of sewage changes according to the water use pattern of citizens. The design hourly maximum wastewater flow was considered as a representative value, and the velocity of this flow should be more than the self-cleansing velocity. This design method requires a steeper gradient than existing design criteria. Therefore, the existing sewer pipelines need to be improved and repaired accordingly. In this study, five types of improvement and repair methods that can maximize the use of existing pipelines and minimize the depth of excavation are proposed. The key technologies utilized are trenchless sewer rehabilitation and complex cross-section pipes. Trenchless sewer rehabilitation is a popular sewage repair method. However, it is complex because the cross-section pipes do not have a universal design and require continuous research and development. In an old metropolis with a combined sewer system, it is difficult to carry out excavation work; hence, the methods presented in this study may be useful in the future.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1197-1202
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• 1998

Organic acids-eggshell calcium salts were prepared to recycle calcium component from discarded egg shells, and the effects of addition of the salts on dough characteristics of raw noodle and physical properties of cooked noodle were also investigated. Based on Farinograms, calcium malate (CM) affected absorption, stability time, and development time more considerably than calcium citrate (CC). Maximum concentrations of both CM and CC with little influence on dough characteristics were found to be 0.1% and 0.4%, respectively. Addition of calcium salts led to reduce the volume expansion rate of cooked noodle and this was more clearly shown in a sample fortified with CM than CC. As for CC, addition of more than 0.6% resulted in rapid increase in springiness which was in a good agreement with sensory evaluation results. Calcium ion concentration of cooked noodle fortified with 0.4% CC was 48 ppm, equivalent to 86 mg of calcium obtained from 200 g of cooked noodle.

• Journal of fish pathology
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• v.2 no.2
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• pp.99-108
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• 1989

Anaethetics are needed for handling fish, especially for transportation, tagging and grading. Among them, MS-222 has been popular in aquaculture since it has an excellent anaesthetic effect. However, MS-222 is more expensive than other chemicals. Benzocaine (Ethyl-p-aminobenzoate) has a similar molecular formula and equivalent anaesthetic effect to MS-222, and is cheaper. The purpose of this study was first to compare anaesthetic effects (Benzocaine) under various conditions : temperature, concentration, pH and body weight. Second purpose was to compare actual anaesthetic effects at 50 ppm benzocaine at ambient temperature and pH for the grading of tilapia. The results of this study are as follows : 1. The effect of anaesthesia at $24^{\circ}C$ was better with low pH, that is 5.6 than high pH 6.6 and 7.6. 2. The anaesthetic effect was not different at different body weight form 11g to 1,350g. 3. The fish were anaesthetized in 4~10 minutes at 50 ppm benzocaine at temperature. $20{\sim}24^{\circ}C$ and pH 6.8~7.3 and recovered in 4~6 minutes when they were put back in the fresh water after 30 minutes anaesthesia. 4. Benzocaine was more sensitive at pH fluctuation than temperature. 5. Twenty four hour-TLm of Benzocaine was 50 ppm at $24^{\circ}C$, pH 6.8 when the fish were put back in the fresh water after 120 minutes.