• Journal of radiological science and technology
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• v.8 no.2
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• pp.65-69
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• 1985

In order to investigate the effects of sulfamonomethoxine (SMM) on thyroid glands in short term administration as medical dose, a total of twenty albino rabbits (mean body weight 1,750g) were selected at random and allotted to control and experimental group. Rabbits in experiment were administered SMM of 50 mg/kg/day for 30 days, and histopathological changes of thyroid glands and the blood levels for T4 and T3 were observed every 5 days. The Results obtained were summarized as follows: 1. The thyroid follicles were decreased or obliterated by highly hypertrophic and hyperplastic epithelial cells and the newly formed small follicles contained scanty colloidal materials. These changes revealed increasing tendency in accordance with the experimental days. 2. The blood levels for T4 and T3 of experimental group manifested significantly decreased values than those of control through the experimental term consistently. Finally, above observations suggest that administration of SMM to animals leads thyroid glands to typical hypofunctional hyperplastic goiter.

• Biomedical Science Letters
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• v.8 no.3
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• pp.167-172
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• 2002

Effect of single administration of Polygala tenuipolia was examined on short-term memory in step through test and the intensity of the immunoreactive c-Fos protein induced by oral administration of ethanol. The acquisition of memory was significantly reduced by ethanol, and ethanol amnesia was remarkably reversed following oral administration of Polygala tenuifolia. c-Fos protein in normal rat brain was highly expressed in order of thalamus, pariental cortex, hippocampus, hypothalamus, amygdaloid and cingulate cortex. The expression of Fos protein was remarkably suppressed by single administration of ethanol. The inhibitory effect of ethanol on expression of Fos protein was reversed by single administration of Polygara tenuipolia, especially tissues of limbic areas such as amygdala, parietal cortex and CA3 of hippocampus. These results suggested that the amelioration process of Polygala tenuipolia on ethanol amnesia seems to be involve the expression of c-Fos protein in partly.

• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.681-692
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• 2019

In this paper, a hybrid deep learning model, called 2D convolution with bidirectional long short-term memory (2DCBLSTM), is presented that can effectively combine both spatial and temporal features for crop classification. In the proposed model, 2D convolution operators are first applied to extract spatial features of crops and the extracted spatial features are then used as inputs for a bidirectional LSTM model that can effectively process temporal features. To evaluate the classification performance of the proposed model, a case study of crop classification was carried out using multi-temporal unmanned aerial vehicle images acquired in Anbandegi, Korea. For comparison purposes, we applied conventional deep learning models including two-dimensional convolutional neural network (CNN) using spatial features, LSTM using temporal features, and three-dimensional CNN using spatio-temporal features. Through the impact analysis of hyper-parameters on the classification performance, the use of both spatial and temporal features greatly reduced misclassification patterns of crops and the proposed hybrid model showed the best classification accuracy, compared to the conventional deep learning models that considered either spatial features or temporal features. Therefore, it is expected that the proposed model can be effectively applied to crop classification owing to its ability to consider spatio-temporal features of crops.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.61-68
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• 2021

The exchange rate is considered a tool improving the volume of exports and reducing imports. This paper aims to determine the impact of the exchange rate on exports and imports between Vietnam and the United States in the context of the trade war. The research uses Autoregressive Distributed Lag (ARDL) and Nonlinear Autoregressive Distributed Lag (NARDL) Model in the time-series data from 2010:1 to 2020:9. The ARDL's results support that real exchange rate impact on export and import volumes, but less than the trade war. The trade war helps trade balance increase 0.35%, while the exchange rate increases trade balance 0.191% when the Vietnamese currency devalues 1% in the long run. In the short term, the real exchange rate makes the trade balance decrease. Therefore, the J curve exists between Vietnam and the U.S. The NARDL expresses that the exchange rate is asymmetric both in the short term and the long term. The findings of this study point to two important elements. Firstly, the exchange rate plays a minor role in exports and imports. Secondly, trade war plays a vital role in increasing exports and imports volume between two countries, and the J curve exists between the two countries.

• Atmosphere
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• v.21 no.4
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• pp.481-495
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• 2011

This study is performed to consider the threshold values of heavy rain warning in Korea using 98 surface meteorological station data and 590 Automatic Weather System stations (AWSs), damage data of National Emergency Management Agency for the period of 2005 to 2009. It is in need to arrange new criteria for heavy rain considering concept of rainfall intensity and rainfall damage to reflect the changed characteristics of rainfall according to the climate change. Rainfall values from the most frequent rainfall damage are at 30 mm/1 hr, 60 mm/3 hr, 70 mm/6 hr, and 110 mm/12 hr, respectively. The cumulative probability of damage occurrences of one in two due to heavy rain shows up at 20 mm/1 hr, 50 mm/3 hr, 80 mm/6 hr, and 110 mm/12 hr, respectively. When the relationship between threshold values of heavy rain warning and the possibility of rainfall damage is investigated, rainfall values for high connectivity between heavy rain warning criteria and the possibility of rainfall damage appear at 30 mm/1 hr, 50 mm/3 hr, 80 mm/6 hr, and 100 m/12 hr, respectively. It is proper to adopt the daily maximum precipitation intensity of 6 and 12 hours, because 6 hours rainfall might be include the concept of rainfall intensity for very-short-term and short-term unexpectedly happened rainfall and 12 hours rainfall could maintain the connectivity of the previous heavy rain warning system and represent long-term continuously happened rainfall. The optimum combinations of criteria for heavy rain warning of 6 and 12 hours are 80 mm/6 hr or 100 mm/12 hr, and 70 mm/6 hr or 110 mm/12 hr.

• Korean Journal of Clinical Pharmacy
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• v.2 no.1
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• pp.11-22
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• 1992

Thymic extract showed antitumor effect to sarcoma mice with higher dose$(200{\mu}g/mouse/day$ i.p., 4weeks) but not with low dose$(5{\mu}g/mouse/day$ i.p., 6 weeks). Direct cytotoxicities were exhibited against sarcoma 180, L1210 and MOLT-4 by MTT assay. The spleen weight of mice were increased but the number of circulating lymphocytes were not increased after long-term(2 weeks) administration of thymic extract. Evaluating the mitogenesis by MTT assay. $\%$ absorbance of human lymphocytes was not increased by thymic extract. Cell cycle statistics of S phase and $G_2/M$ phase was not increased in the presence of that by PI staining. The formation of rosette was induced, irrespectively of exposure time short-term(l hour) and long-term(2 weeks). The population of mouse blood T-cell to bind Lyt2-antimonoclonal antibody and to $L_2T_4$ were increased after administration of thymic extract$(2-200{\mu}g/mouse/day)$. From the above results, it is suggested that thymic extract exerts antitumor activity by stimulating T cells to differeniate in vivo but not in vitro.

• Agribusiness and Information Management
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• v.10 no.1
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• pp.26-34
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• 2018

Development, availability and users' participation in the information service of agricultural food sector is slower than that of other sectors in Korea. This phenomenon comes from the lack of development strategies and comparative analyses with other sectors, as well as the agricultural food industry's own characteristics which is developed based on the offline market. In this research, we will discuss about how to improve the public information service of agricultural food sector based on the example of establishing service improvement strategy by the most representative Okdab. In this research, we have drawn the following implications for development strategy of Okdab service based on three core keywords derived from benchmarking KOSIS. Three core subjects for upgrading public information service are 'analysis information with expertise and differentiation,' 'user cooperation-oriented platform,' and 'intuitive nd effective UX,' and to strength B.I. as an integrated information service of agricultural food sector, we need to identify the users' satisfaction and needs for the existing service, establish an optimized operating strategy on a short-term, mid-term and long term bases, and implement them in a positive way. Based on this positive action, it can become a trustworthy information service for the users, and we can expect the improvement of the users' recognition for its consistent usability and efficiency.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.855-860
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• 2005

This study was designed to test the effects of changes in energy and protein intake levels on the maternal milk amino acid concentrations over the short-term in lactating mares. Three lactating mares were enrolled for the study 7 weeks after parturition. A low-energy and low-protein diet (LEP) was administered during the first week of the study, followed by administration of a high-energy and high-protein diet (HEP), again for a week (day 1 to day 7), and milk was sampled thrice daily at intervals of 8 h during the study period. The mean amino acid concentrations in the maternal milk, except for those of proline, serine and valine, were significantly higher in the HEP feeding period than during the LEP feeding period (p<0.05). The sum of the concentrations of all the amino acids (TAA) in the maternal milk samples during the HEP and LEP feeding periods was 1,644.9${\pm}$26.9 and 1,542.3${\pm}$36.0 mg/100 g, respectively, the difference between the two was not significant. When the ratio of each amino acid concentration to the TAA in the maternal milk was analyzed, there were significant differences between the HEP and LEP feeding periods for all amino acids, except glycine, serine, alanine and histidine. It was found that the concentrations of glutamic acid+glutamine, serine, threonine, arginine and valine were significantly higher (p<0.05) on day 1 than on day 7 during the LEP feeding period, and there were no such differences during the HEP feeding period. In regard to the effects of changes in the energy and protein intake levels in lactating mares, no changes in milk amino acid concentrations were found following administration of HEP for a week, whereas 7 days of administration of LEP was associated with a decrease in the amino acid concentrations.

• Toxicological Research
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• v.25 no.1
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• pp.51-58
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• 2009

Carrageenan is a naturally-occurring sulfated polygalactan which has been widely used in the dairy industry and a gelling agent in non-dairy products. In this study, four short-term in vitro genotoxicity assays were investigated to evaluate the potential genotoxic effects of carrageenan. The mutagenicity of carrageenan was evaluated up to a maximum dose of 5 mg/plate in Ames test. There was no increase in the number of revertant colonies compared to its negative control at any dose in all of strains tested. To assess clastogenic effect, the in vitro chromosomal aberration assay was performed using Chinese hamster lung cells. Carrageenan was not considered to be clastogenic in this assay at up to the highest feasible concentration which could be evaluated. The in vitro comet assay and micronucleus test results obtained on L5178Y cells also revealed that carrageenan has no genotoxicity potential, although there was a marginal increase in micronuclei frequencies and DNA damage in the respective micronucleus and comet assays. Taken together, our results indicate that carrageenan was not genotoxic based on four in vitro genotoxicity results.

• Journal of Environmental Health Sciences
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• v.49 no.3
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• pp.149-158
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• 2023

Background: Injury is one of the major health problems in South Korea. Few studies have evaluated both intentional and unintentional injury when investigating the association between exposure to air pollutants and injury. Objectives: We aimed to explore the association between short-term exposure to ambient air pollution and years of life lost (YLLs) due to injury. Methods: Data on daily YLLs for 2002~2019 were obtained from the the Death Statistics Database of the Korean National Statistical Office. This study estimated short-term exposure to particulate matter with an aerodynamic diameter of <10 ㎛ (PM₁₀), particulate matter with an aerodynamic diameter of <2.5 ㎛ (PM_2.5), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and ozone (O₃). This time series study was conducted using a generalized additive model (GAM) assuming a Gaussian distribution. We also evaluated a delayed effect of ambient air pollution by constructing a lag structure up to seven days. The best-fitting lag was selected based on smallest generalized cross validation (GCV) value. To explore effect modification by intentionality of injury (i.e., intentional injury [self-harm, assault] and unintentional injury), we conducted stratified subgroup analyses. Additionally, we stratified unintentional injury by mechanism (traffic accident, fall, etc.). Results: During the study period, the average daily YLLs due to injury was 307.5 years. In the intentional injury, YLLs due to self-harm and assault showed positive association with air pollutants. In the unintentional injury, YLLs due to fall, electric current, fire and poisoning showed positive association with air pollutants, whereas YLLs due to traffic accident, mechanical force and drowning/submersion showed negative associations with air pollutants. Conclusions: Injury is recognized as preventable, and effective strategies to create a safe society are important. Therefore, we need to establish strategies to prevent injury and consider air pollutants in this regard.