• Journal of Energy Engineering
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• v.29 no.2
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• pp.68-78
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• 2020

According to the new climate change agreement, technology development to reduce greenhouse gases is actively conducted worldwide, and research on energy efficiency improvement in the field of power generation and transmission and distribution is underway [1,2]. Economic analysis of the operation method of storing and supplying surplus electricity using energy storage devices, and using energy storage devices as a frequency adjustment reserve power in regional cogeneration plants has been reported as the most profitable operation method [3-7]. Therefore, this study conducted an economic analysis for the installation of energy storage devices in the combined heat and power plant in the Czech Republic. The most important factor in evaluating the economics of battery energy storage devices is the lifespan, and the warranty life is generally 10 to 15 years, based on charging and discharging once a day. For the simulation, the ratio of battery and PCS was designed as 1: 1 and 1: 2. In general, the primary frequency control is designed as 1: 4, but considering the characteristics of the cogeneration plant, it is set at a ratio of up to 1: 2, and the capacity is simulated at 1MW to 10MW and 2MWh to 20MWh according to each ratio. Therefore, life was evaluated based on the number of cycles per year. In the case of installing a battery energy storage system in a combined heat and power plant in the Czech Republic, the payback period of 3MW / 3MWh is more favorable than 5MW / 5MWh, considering the local infrastructure and power market. It is estimated to be about 3 years or 5 years from the simple payback period considering the estimated purchase price without subsidies. If you lower the purchase price by 50%, the purchase cost is an important part of the cost for the entire lifetime, so the payback period is about half as short. It can be, but it is impossible to secure profitability through the economy at the scale of 3MWh and 5MWh. If the price of the electricity market falls by 50%, the payback period will be three years longer in P1 mode and two years longer in P2 and P3 modes.

• The Korean Journal of Pharmacology
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• v.31 no.3
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• pp.365-375
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• 1995

The anemia-inducing strain of Friend virus (FVA) is a murine retrovirus which stimulates the proliferation of erythroid progenitor cells. The progenitor cells synthesized by FVA-stimulation are unable to proceed with differentiation and accumulate in the spleen resulting in splenomegaly in infected mice. Using FVA-inoculated mice as a model, we have investigated the antiretroviral effects of 2',3'-dideoxycytidine (ddC) and recombinant $interferon-{\alpha}-A\;(rIFN-{\alpha}-A)$ on FVA infection. The extent of the infection was determined by measuring the weights of the spleens. Daily intraperitoneal injection of ddC (100 mg/kg body weight), $rIFN-{\alpha}-A$ (10 KU/mose) and the combination of both drugs to FVA inoculated mice for 18 days resulted in suppression of the growth of spleens by 15.1%, 52.7% and 61.6%, respectively. When ddC was dissolved in drinking water (0.1 mg/ml) and administered to a group of FVA inoculated mice ad libitum, and $rIFN-{\alpha}-A$ (10 KU/mouse) was intraperitoneally injected daily to another group of ddC (0.1 mg/ml) drinking mice for 18days, the growth of spleens was suppressed by 38.4% and 83.2%, respectively. These results indicate that administration of ddC via drinking water is more effective in suppressing FVA infection than the daily injection of ddC, and that the combined effects ddC and $rIFN-{\alpha}-A$ are not synergistic but additive. In order to determine whether ddC treatment alters the characteristic of the progenitor cells with respect to $Ca^{++}$ uptake, $Ca^{++}$ uptake in erythroid cells and the effect of cyclohexyladenosine (CHA) on the $Ca^{++}$ uptake were studied. $Ca^{++}$ uptake in the erythroid progenitor cells was about 20-fold greater than in mouse erythrocytes and the inhibition of $Ca^{++}$ uptake by CHA was the greatest in the progenitor cells from FVA infected mice which were treated with ddC. The inhibition was obviated by theophylline. Results of CHA binding studies showed that the erythroid progenitor cells contain both high and low affinity CHA binding sites, whereas mose erythrocytes contain only the low affinity CHA binding sites.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.7 no.1
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• pp.34-43
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• 1996

In adolescence, the symptoms of depression are more various and different from those of adult. Conduct behaviours are frequently represented in adolescent's depression. The patients who have the depression and conduct disorder are defined as depressive condor disorder in ICD-10. We hypothesized that there might be different parental rearing patterns between the patients with depression alone and the depressive conduct disorder. We applied children's depression inventory (CDI), parental rating form for conduct disorder based on DSM-III-R, and parental bonding instrument (PBI) to patients and normal control adolescent group. The results were as follows : 1) There were no significant differences in severity of depressive symptoms, maternal care, maternal overprotection, and paternal care. 2) Paternal overprotection showed significant higher scores in depressive conduct disorder group than depression group and normal control group. 3) There were positive correlations in the severity of depressive symptoms and behavior problems in all subjects. 4) There were no correlations in maternal care and overprotecion with conduct problems, but with depressive symptoms in all subject. 4) There were no correlations in paternal care with conduct problems and depressive symptoms in all subjects. 5) There were significant correlations in patienral overprotective, intrusive attitudes with conduct problems, not with depressive symptoms in all subjects.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.46-54
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• 2022

Known for its effectiveness in weight loss and diabetes prevention, Gymnema sylvestre products can be found in the US, Japanese, and Indian markets. However, the recommended dosage or safety of these products has not yet been proven. Therefore, development of an analytical method for detecting the content of Gymnema sylvestre in food products is required. Accordingly, this study proposes an analysis method that can examine Gymnema sylvestre in food using LC-ESI-MS/MS and KASP (Kompetitive Allele-Specific PCR) markers. In LC-ESI-MS/MS, a simultaneous analysis method for gymnemic acid and deacylgymnemic acid was optimized using negative ionization mode, and its validation test was completed for solid and liquid samples. In addition, KASP markers were prepared by finding the specific SNP of G. sylvestre in ITS2 and matK through DNA barcodes. The two KASP markers returned positive FAM fluorescence result when combined with G. sylvestre, and this aspect was confirmed in raw G. sylvestre as well. The applicability of the method was tested on 21 different food and healthy functional products containing G. sylvestre purchased on the internet. As a result, although there was a difference in the ratios of gymnemic acid and deacylgymnemic acid in LC-ESI-MS/MS, the index component was detected in all 21 products samples. In the KASP analysis, 9 products returned positive FAM result, and the rest of the products were found to be containing G. sylvestre extract. This study is the first study to use the dual system of LC-ESI-MS/MS and KASP for the analysis of G. sylvestre. The study has confirmed that these two methods are applicable to the examine G. sylvestre content in food products.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.106-111
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• 1998

This study has been focused on both estrogenic and proliferating activity of genistein (GEN) and bisphenol A (BPA). GEN and BPA enhance the proliferation of estrogen-dependent MCF-7 human breast cancer cells at concentrations as low as 100 nM of GEN and 8 ng/ml of BP A achieving similar effect to that of estradiol at 1 nM. Expression of the estrogen responsive gene, pS2 was also induced in MCF-7 cells by treatment with genistein at dose as low as 1 nM and BPA at dose as low as 4 ng/ml. Using 21 day-old ovariectomized nude mice, we examined end-bud formation and mammary gland development after treatment with bisphenol A or genistein. Compared with untreated control, mammary gland development and end-bud formation were significantly increased in mice fed genistein or bisphenol A (p<0.05). Taken together, it is concluded that GEN and BP A can act as an estrogen agonist resulting in cell proliferation and induction of the estrogen responsive pS2 gene in MCF-7 cells in vitro and in athymic mice in vivo, respectively. Therefore, it is suggested that GEN and BP A might modulate human endocrine system and these compounds might be considered as a endocrine modulator at the low levels of doses.

• Applied Biological Chemistry
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• v.17 no.3
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• pp.219-234
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• 1974

A series of experiments was conducted to study the behavior of the phosphorus added to the soils having the high phorphorus fixing capacity derived from volcanic ash in Cheju Island. Soil samples were taken from different depths of 0-10, 10-30, and 30-50cm in six citrus orchards where heavy application of phosphate fertilizer has been practised. Various forms of phosphorus were determined and phosphorus adsorption experiments were performed. The results obtained can be summarized as follows: 1. The content of inorganic phosphorus fractions determined by the method of Chang and Jackson was: water soluble P

• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.28-40
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• 2004

Box experiments were performed to evaluate the removal efficiency of SVE (soil vapor extraction) for gasoline in soil. An activated carbon sorption tower and a biofilter were operated as post-treatment processes to remove VOCs extracted from extraction wells of SVE. An acrylic resin box (65 cm${\times}$20 cm${\times}$30 cm) was used to make artificial soil layers and two injection wells and one extraction well were built for SVE process in the box. Gases from extraction wells flew into the activated carbon sorption tower or the biofilter. Gasoline concentrations of VOCs emitted from the extraction well were compared with those after post treatments. More than 92% of initial gasoline mass in soil were removed by SVE within few days, suggesting that SVE is very available to remove VOCs from contaminated soils. To treat VOCs from extraction wells of SVE, an activated carbon sorption tower and a biofilter were attached to SVE process and their gasoline removal efficiencies were measured. These post treatment systems lowered gasoline concentrations to below 1.0 ppm within few days. Average remediation efficiency was 98% of gasoline for the activated carbon sorption tower and 84.1% for the biofilter. The maximum removal capacity of a biofilter was 10.7 g/L/hr, which was ten times higher than general biofilter removal capacity. Results from the study suggest that the activated carbon sorption tower and the biofilter would be available for the post treatment process to remove VOCs generated from SVE process.

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.227-249
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• 2016

Arsenic and its compounds vary in their toxicity according to the chemical forms. Inorganic arsenic is more toxic and known as carcinogen. The provisional tolerable weekly intake (PTWI) of $15{\mu}g/kg$ b.w./week established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has been withdrawn, while the EFSA panel suggested $BMDL_{0.1}$ $0.3{\sim}8{\mu}g/kg\;b.w./day$ for cancers of the lung, skin and bladder, as well as skin lesions. Rice, seaweed and beverages are known as food being rich in inorganic arsenic. As(III) is the major form of inorganic arsenic in rice and anaerobic paddy soils, while most of inorganic arsenic in seaweed is present as As(V). The inorganic arsenic in food was extracted with solvent such as distilled water, methanol, nitric acid and so on in heat-assisted condition or at room temperature. Arsenic speciation analysis was based on ion-exchange chromatography and high-performance liquid chromatography equipped with atomic absorption spectrometry and inductively coupled plasma mass spectrometry. However, there has been no harmonized and standardized method for inorganic arsenic analysis internationally. The inorganic arsenic exposure from food has been estimated to range of $0.13{\sim}0.7{\mu}g/kg$ bw/day for European, American and Australian, and $0.22{\sim}5{\mu}g/kg$ bw/day for Asian. The maximum level (ML) for inorganic arsenic in food has established by EU, China, Australia and New Zealand, but are under review in Korea. Until now, several studies have conducted for reduction of inorganic arsenic in food. Inorganic arsenic levels in rice and seaweed were reduced by more polishing and washing, boiling and washing, respectively. Further research for international harmonization of analytical method, monitoring and risk assessment will be needed to strengthen safety management of inorganic arsenic of foods in Korea.

• Analytical Science and Technology
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• v.22 no.4
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• pp.336-344
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• 2009

This survey was carried out to estimate the contents of heavy metals (Hg, Pb, Cd, and As) in 10 kinds of dried marine products (n=189) which are closely related to food resources. The contents of heavy metals were estimated by inductively coupled plasma spectrometer (ICP) and mercury analyzer. The values of heavy metals in dried marine products were as follows (Mean${\pm}$SD (range), mg/kg). The average contents of heavy metals in the dried marine products were Hg $0.058{\pm}0.069$ (0.002~0.502) mg/kg, Pb $0.178{\pm}0.598$ (ND~5.130) mg/kg, Cd $0.306{\pm}0.610$ (ND~6.802) mg/kg, As $5.282{\pm}6.158$ (ND~71.760) mg/kg. The range of heavy metal contents in dried marine products are low level, except of lead contents (n=2). In the comparison of heavy metal content by anchovy size, it was shown that cadmium, mercury and arsenic were meaningfully different. The contents of heavy metals by the shape of shrimp and Alaska Pollack were shown that the result of each group was meaningless. In the comparison imported production with domestic production, in the case of common squid, cadmium and arsenic were meaningfully different. The weekly average intakes of Hg, Pb and Cd from dried marine products takes about 1.17~11.52% of PTWI (Provisional Tolerable Weekly Intakes) that FAO/WHO Joint Food Additive and Contaminants Committee has set to evaluate their safeties.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.2
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• pp.147-155
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• 2024

Gallium-68-prostate-specific membrane antigen-11 (⁶⁸Ga-PSMA-11) is a positron emission tomography radiopharmaceutical that labels a Glu-urea-Lys-based ligand with ⁶⁸Ga, binding specifically to the PSMA. It is used widely for imaging recurrent prostate cancer and metastases. On the other hand, the preparation and quality control testing of ⁶⁸Ga-PSMA-11 in medical institutions takes over 60 minutes, limiting the daily capacity of ⁶⁸Ge/⁶⁸Ga generators. While the generator provides 1,110 MBq (30 mCi) nominally, its activity decreases over time, and the labeling yield declines irregularly. Consequently, additional preparations are needed, increasing radiation exposure for medical technicians, prolonging patient wait times, and necessitating production schedule adjustments. This study aimed to reduce the ⁶⁸Ga-PSMA-11 preparation time and optimize the automated synthesis system. By shortening the reaction time between ⁶⁸Ga and the PSMA-11 precursor and adjusting the number of purification steps, a faster and more cost-effective method was tested while maintaining quality. The final synthesis time was reduced from 30 to 20 minutes, meeting the standards for the HEPES content, residual solvent EtOH content, and radiochemical purity. This optimized procedure minimizes radiation exposure for medical technicians, reduces patient wait times, and maintains consistent production schedules, making it suitable for clinical application.