• Journal of Veterinary Clinics
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• v.26 no.2
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• pp.138-143
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• 2009

Ischemia/reperfusion injury(I/RI) is the major cause of acute renal failure and delayed graft function(DGF) unavoidable in renal transplantation. Enormous studies on ischemia damage playing a role in activating graft rejection factors, such as T cells or macrophages, are being reported. Present study was performed to determine whether ischemia time would play an important role in activating rejection-related factors or not in rat models of I/RI. Male Sprague-Dawley rats were submitted to 30, 45, and 60 minutes of warm renal ischemia with nephrectomy or control animals underwent sham operation(unilateral nephrectomy). Renal function and survival rates were evaluated on day 0, 1, 2, 3, 5 and 7. Immunofluorescence staining of dendritic cells(DCs), natural killer(NK) cells, macrophages, B cells, CD4+ and CD8+ T cells were measured on day 1 and 7 after renal I/RI. Survival rates dropped below 50% after day 3 in 45 minutes ischemia. Histologic analysis of ischemic kidneys revealed a significant loss of tubular architecture and infiltration of inflammatory cells. DCs, NK cells, macrophages, CD4+ and CD8+ T cells were infiltrated from a day after I/RI depending on ischemia time. Antigen presenting cells(DCs, NK cells or macrophages) and even T cells were infiltrated 24 hours post-I/RI, which is at the time of acute tubular necrosis. During the regeneration phase, not only these cells increased but B cells also appeared in more than 45 minutes ischemia. The numbers of the innate and the adaptive immune cells increased depending on ischemia as well as reperfusion time. These changes of infiltrating cells resulting from each I/RI model show that ischemic time plays a role in activating rejection related immune factors and have consequences on progression of renal disease in transplanted and native kidneys.

• Journal of fish pathology
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• v.22 no.3
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• pp.263-273
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• 2009

There is an increasing number of reports describing Streptococcus parauberis as an important pathogen of cultured olive flounder Paralichthys olivaceus and starry flounder Platichthys stellatus in Korea. We tried to determine the effects of water temperature (14${^{\circ}C}$ and 21${^{\circ}C}$) on the pathogenicity in Streptococcal disease caused by S. parauberis. We have challenged 180 olive flounder by i.p injection to $2.0{\times}10^{7}$ live cells/fish. Mortality was monitored for 21 days post challenge. And histopathological characterizations as infection degree, tissue degeneration and/or bacterial distribution were investigated with H&E stain and in situ hybridization technique. Fifty percent and 16.7% of mortality occurred within 21 days at 21${^{\circ}C}$ and 14${^{\circ}C}$ water temperature, respectively. In most cases, the typical symptoms of olive flounder infected with S. parauberis were darkness of the skin, lethargy, mild abdominal distension cause by ascites, splenomegaly, congested liver and internal organs paleness. The pericardial sac contained large amounts of cloudy fluid. Numerous whitish nodules, which were variable in size and often confluent, were randomly scattered throughout the myocardium. Especially, pericarditis and/or myocarditis was observed in all tested fishes after death. Positive in reaction with S. parauberis were found in all tissues in situ hybridization analysis. The relative numbers of S. parauberis in heart were much more than in liver, spleen, kidney and stomach. We evaluated that S. parauberis strain causes serious damage in the pericardium, shortness of breath and the blood disorder. Therefore, pericarditis and myocarditis caused by S. parauberis were closely related to mortality of olive flounder.

• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.293-303
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• 2012

Recently, as construction technology improved, concrete structures not only became larger, taller and longer but were able to perform various functions. However, if extreme loads such as impact, blast, and fire are applied to those structures, it would cause severe property damages and human casualties. Especially, the structural responses from extreme loading are totally different than that from quasi-static loading, because large pressure is applied to structures from mass acceleration effect of impact and blast loads. Therefore, the strain rate effect and damage levels should be considered when concrete structure is designed. In this study, the low velocity impact loading test of steel fiber reinforced concrete (SFRC) slabs including 0%~1.5% (by volume) of steel fibers, and strengthened with two types of FRP sheets was performed to develop an impact resistant structural member. From the test results, the maximum impact load, dissipated energy and the number of drop to failure increased, whereas the maximum displacement and support rotation were reduced by strengthening SFRC slab with FRP sheets in tensile zone. The test results showed that the impact resistance of concrete slab can be substantially improved by externally strengthening using FRP sheets. This result can be used in designing of primary facilities exposed to such extreme loads. The dynamic responses of SFRC slab strengthened with FRP sheets under low velocity impact load were also analyzed using LS-DYNA, a finite element analysis program with an explicit time integration scheme. The comparison of test and analytical results showed that they were within 5% of error with respect to maximum displacements.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.477-484
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• 2001

Background: Initial symptoms for esophageal perforation have not been clarified, but when there is no early diagnosis and proper treatment to follow immediately after the diagnosis, it is fatal for the patients. Therefore, this study attempted to discover the factors that influence the prognosis of esophageal perforation to contribute to the improvement of the treatment result. Material and Method: The subjects of this study are 32 patients who came to the hospital with esophageal perforation from October, 1984 to June, 2000. This study examined the items for clinical observation such as patients' sex, age, cause of the perforation, perforation site, the time spent until the beginning of the treatment, symptoms caused by the perforation and its complication, and treatment methods. This study tried to find out the relationship between the survival of patients and each item. Result: There were 24 male and 8 female patients and their mean age was 49.7+16.4. For the causes of perforation, there were 14 cases(43%) of iatrogenic perforation, which ranked first, caused by the medical instrument operation and surgical damage. As for the perforation sites, thoracic esophagus was the most common site(26 cases of 81.2%) and chest pain was the most frequent symptom. The complication caused by esophageal perforation showed the highest cases in the order of mediastinitis, empyema, sepsis and peritonitis. After the treatment, there were 23 cases of survival and 9 cases of mortality. The total mortality rate was 28.1% and the main causes of mortality were sepsis and acute respiratory distress syndrome(ARDS). As for the treatment, 8 cases(25.0%) treated the perforation successfully using conservative treatment only. As for the surgical treatment, there were 5 cases(15.6%) of cervical drainage, 7 cases (21.8%) of primary repair and 12 cases(37.5%) of esophageal reconstruction after performing an exclusion-diversion. There were 18 cases(56.2%) of complete treatment of esophageal perforation at its initial treatment and in 14 cases(43.8%) of treatment failure at its initial treatment, patients were completely cured in the next treatment stage or died during the treatment. The cases of perforation in thoracic esophagus, complication into severe mediastinitis or sepsis and the cases of failure at initial treatment showed a statistically significant mortality rate (p<0.05).

• Korean journal of applied entomology
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• v.57 no.4
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• pp.339-345
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• 2018

The sugar beet cyst nematode (SBCN), Heterodera schachtii first detected in Taebaek, Gangwon-do in 2011, is one of the major plant parasitic nematodes that cause economic damage to the Chinese cabbage in highland regions. In addition, the distribution of clover cyst nematode (CCN), H. trifolii was confirmed in the highland Chinese cabbage cultivated regions in 2017. In order to investigate the spread of cyst nematodes, this study has been conducted since 2013 in the highland Chinese cabbage cultivation area. In addition, in 2017, the Real-Time PCR technique with the species-specific primer was used to investigate those two cyst nematodes and the soybean cyst nematode (SCN), H. glycines which is known for its distribution in Korea, focusing on the main production regions of highland Chinese cabbage cultivation. The number of infected fields in the Chinese cabbage plantation in highland increased every year to confirm distribution in Taebaek, Samcheok, Jeongseon and Gangneung in 2017, and the cumulative number of infection fields reached 245 by 2017. Of the 41 possible cyst nematode samples for PCR analysis, 61% were CCN, only 9.8% of the SBCN and 29.3% of the SCN were identified. Therefore, some of the previously known SBCN or CCN discoveries are likely to have been infected with SCN. It is believed that the CCN needs to be controlled in the future as CCN have been found to be dominant species in the highland Chinese cabbage plantation regions.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.658-673
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• 2018

Social conflicts with extremely low frequency magnetic field(ELF-MF) exposures are expected to exacerbate due to continued increase in electric power demand and construction of high voltage transmission lines(HVTL). However, in current environmental impact assessment(EIA) act, specific guidelines have not been included concretely about EIA of ELF-MF. Therefore, this study conducted a standardization study on EIA method through case analysis, field measurement, and expert consultation of the EIA for the ELF-MF near HVTL which is the main cause of exposures. The status of the EIA of the ELF-MF and the problem to be improved are derived and the EIA method which can solve it is suggested. The main contents of the study is that the physical characteristics of the ELF-MF affected by distance and powerload should be considered at all stages of EIA(survey of the current situation - Prediction of the impacts - preparation of mitigation plan ? post EIA planning). Based on this study, we also suggested the 'Measurement method for extremely low frequency magnetic field on transmission line' and 'Table for extremely low frequency magnetic field measurement record on transmission line'. The results of this study can be applied to the EIA that minimizes the damage and conflict to the construction of transmission line and derives rational measures at the present time when the human hazard to long term exposure of the ELF-MF is unclear.

• Korean Journal of Remote Sensing
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• v.38 no.6_2
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• pp.1723-1735
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• 2022

Landslides are one of the most prevalent natural disasters, threating both humans and property. Also landslides can cause damage at the national level, so effective prediction and prevention are essential. Research to produce a landslide susceptibility map with high accuracy is steadily being conducted, and various models have been applied to landslide susceptibility analysis. Pixel-based machine learning models such as frequency ratio models, logistic regression models, ensembles models, and Artificial Neural Networks have been mainly applied. Recent studies have shown that the kernel-based convolutional neural network (CNN) technique is effective and that the spatial characteristics of input data have a significant effect on the accuracy of landslide susceptibility mapping. For this reason, the purpose of this study is to analyze landslide vulnerability using a pixel-based deep neural network model and a patch-based convolutional neural network model. The research area was set up in Gangwon-do, including Inje, Gangneung, and Pyeongchang, where landslides occurred frequently and damaged. Landslide-related factors include slope, curvature, stream power index (SPI), topographic wetness index (TWI), topographic position index (TPI), timber diameter, timber age, lithology, land use, soil depth, soil parent material, lineament density, fault density, normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used. Landslide-related factors were built into a spatial database through data preprocessing, and landslide susceptibility map was predicted using deep neural network (DNN) and CNN models. The model and landslide susceptibility map were verified through average precision (AP) and root mean square errors (RMSE), and as a result of the verification, the patch-based CNN model showed 3.4% improved performance compared to the pixel-based DNN model. The results of this study can be used to predict landslides and are expected to serve as a scientific basis for establishing land use policies and landslide management policies.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.373-383
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• 2022

Inflammation caused by active oxygen and the resulting barrier damage have been consistently pointed out as the cause of wrinkle formation. In this study, effective index ingredient search and efficacy analysis were performed to verify the value of use as a functional cosmetic material related to antioxidant, anti-inflammatory and skin barrier improvement, and anti-aging for extracts of four types of Eleutherococcus divaricatus var. chiisanensis (ED), Eleutherococcus senticosus (EN), Eleutherococcus sessiliflorus (ES), and Eleutherococcus sieboldianus (EI) belonging to the Eleutherococcus genus. To identify the effective index composition, the content of the ingredients was measured by high-performance liquid chromatography. The content of eleutheroside E and chlorogenic acid was the highest in ED among the Eleutherococcus genus. As for anti-oxidant activity, DPPH radical scavenging activity was the highest in ED. In anti-inflammatory effects, ED extracts inhibited nitric oxide generation in inflammatory macrophage cells due to lipopolysaccharide by 40% at 100 ㎍/mL. In the case of IL-6 inhibition, which is known as a pro-inflammatory cytokine, ED showed 41% inhibition at 100 ㎍/mL. In addition, filaggrin and involucrin, which are skin barrier-related factors, were increased by 2.5 times and 1.6 times, respectively, in 100 ㎍/mL of ED extracts, and as for the collagenase, which is a wrinkle-related factor, ED extract showed 29% efficacy at 100 ㎍/mL. Thus, these result suggested that ED extract, among the four Eleutherococcus genus, can be used as a cosmetic ingredient for suppressing inflammation in the skin, reinforcing the skin barrier, and reducing wrinkles.

• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.57-70
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• 2023

In recent years, the frequency of warnings about particulate matter (PM) has gradually increased in Korea, along with an increase in its intensity. Because of their vast surface area, reactivity to external particles, and characteristics of their leaves, urban trees can act as biofilters, reducing PM pollution. However, the air pollutant PM can cause various types of damage not only to human health but also to vegetation. Studies performed to date on the responses of trees to PM are still insufficient. Here, we analyzed the correlation between PM adsorption and physiological and biochemical responses of four major street tree species, namely, Abies holophylla, Acer buergerianum, Pinus densiflora, and Quercus variabilis, under conditions of approximately 300 ㎍ m^-3 of fly ash emissions using a phytotron. The results showed that the physiological and biochemical responses and PM adsorption differed depending on the tree species. In correlation analysis, it was confirmed that there were positive correlations between physiological factors, and PM adsorption on adaxial leaf surfaces negatively impacted the physiological characteristics. This study provides fundamental information for selecting tree species to reduce PM pollution and develop sustainable urban forests.