• Restorative Dentistry and Endodontics
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• v.34 no.3
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• pp.169-176
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• 2009

Diabetes Mellitus (DM) is a syndrome accompanied with the abnormal secretion or function of insulin, a hormone that plays a vital role in controlling the blood glucose level (BGL). Type land 2 DM are most common form and the prevalence of the latter is recently increasing, The aim of this article was to assess whet her Type 2 DM could act as a predisposing risk factor on the pulpo-periapical pathogenesis. Previous literature on the pathologic changes of blood vessels in DM was thoroughly reviewed. Furthermore, a histopathologic analysis of artificially-induced periapical specimens obtained from Type 2 diabetic and DM-resistant rats was compared. Histopathologic results demonstrate that the size of periapical bone destruction w as larger and the degree of pulpal inflammation was more severe in diabetic rats, indicating that Type 2 D M itself can be a predisposing risk factor that makes the host more susceptible to pulpal infection. The possible reasons may be that in diabetic state the lumen of pulpal blood vessels are thickened by atheromatous deposits, and microcirculation is hindered, The function of polymorphonuclear leukocyte is also impair ed and the migration of immune cells is blocked, leading to increased chance of pulpal infection. Also, lack of collateral circulation of pulpal blood vessels makes the pulp more susceptible to infection. These decrease the regeneration capacity of pulpal cells or tissues, delaying the healing process, Therefore, when restorative treatment is needed in Type 2 DM patients, dentists should minimize irritation to the pulpal tissue un der control of BGL.

• Journal of KIISE:Information Networking
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• v.30 no.3
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• pp.329-342
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• 2003

Most of the existing multicast routing protocols for ad-hoc networks do not take into account the efficiency of the protocol for the cases when there are large number of sources in the multicast group, resulting in either large overhead or poor data delivery ratio when the number of sources is large. In this paper, we propose a multicast routing protocol for ad-hoc networks, which particularly considers the scalability of the protocol in terms of the number of sources in the multicast groups. The proposed protocol designates a set of sources as the core sources. Each core source is a root of each tree that reaches all the destinations of the multicast group. The union of these trees constitutes the data delivery mesh, and each of the non-core sources finds the nearest core source in order to delegate its data delivery. For the efficient operation of the proposed protocol, it is important to have an appropriate number of core sources. Having too many of the core sources incurs excessive control and data packet overhead, whereas having too little of them results in a vulnerable and overloaded data delivery mesh. The data delivery mesh is optimally reconfigured through the periodic control message flooding from the core sources, whereas the connectivity of the mesh is maintained by a persistent local mesh recovery mechanism. The simulation results show that the proposed protocol achieves an efficient multicast communication with high data delivery ratio and low communication overhead compared with the other existing multicast routing protocols when there are multiple sources in the multicast group.

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.597-605
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• 2014

The continuous observations for atmospheric aerosols were conducted during 3 years (2009 to 2011) by using Gwangju Institute of Science and Technology (GIST) multi-wavelength Raman lidar at Gwangju, Korea ($35.10^{\circ}N$, $126.53^{\circ}E$). The aerosol depolarization ratios calculated from lidar data were used to identify the Asian dust layer. The optical properties of Asian dust layer were different according to its vertical distribution. In order to investigate the difference between the optical properties of each individual dust layers, the transport pathway and the transport altitude of Asian dust were analyzed by Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. We consider that the variation of optical properties were influenced not only their transport pathway but also their transport height when it passed over anthropogenic pollution source regions in China. The lower particle depolarization ratio values of $0.12{\pm}0.01$, higher lidar ratio of $67{\pm}9sr$ and $68{\pm}9sr$ at 355 nm and 532 nm, respectively, and higher ${\AA}ngstr\ddot{o}m$ exponent of $1.05{\pm}0.57$ which are considered as the optical properties of pollution were found. In contrast with this, the higher particle depolarization ratio values of $0.21{\pm}0.09$, lower lidar ratio of $48{\pm}5sr$ and $46{\pm}4sr$ at 355 nm and 532 nm, respectively, and lower ${\AA}ngstr\ddot{o}m$ exponent of $0.57{\pm}0.24$ which are considered as the optical properties of dust were found. We found that the degree of mixing of anthropogenic pollutant aerosols in mixed Asian dust govern the variation of optical properties of Asian dust and it depends on their altitude when it passed over the polluted regions over China.

• Journal of Soil and Groundwater Environment
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• v.11 no.3
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• pp.31-42
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• 2006

Drought indices, such as PDSI (palmer Drought Severity Index), SWSI (Surface Water Supply Index) and SPI (Standardized Precipitation Index), have been developed to assess and forecast an intensity of drought. To find the applicability of groundwater level data to a drought assessment, a correlation analysis between SPI and groundwater levels was conducted for each time series at a drought season in 2001. The comparative results between SPI and groundwater levels of shallow wells of three national groundwater monitoring stations, Chungju Gageum, Yangpyung Gaegun, and Yeongju Munjeong, show that these two factors are highly correlated. In case of SPI with a duration of 1 month, cross-correlation coefficients between two factors are 0.843 at Chungju Gageum, 0.825 at Yangpyung Gaegun, and 0.737 at Yeongju Munjeong. The time lag between peak values of two factors is nearly zero in case of SPI with a duration of 1 month, which means that groundwater level fluctuation is similar to SPI values. Moreover, in case of SPI with a duration of 3 month, it is found that groundwater level can be a leading indicator to predict the SPI values I week later. Some of the national groundwater monitoring stations can be designated as DIW (Drought Index Well) based on the detailed survey of site characteristics and also new DIWs need to be drilled to assess and forecast the drought in this country.

• Journal of Korea Water Resources Association
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• v.51 no.1
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• pp.11-18
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• 2018

The climate change impacts on hydrological components and water balance in Jeju Island were evaluated using multiple climate models and watershed model, SWAT-K. To take into account the uncertainty of the future forecast data according to climate models, climate data of 9 GCMs were utilized as weather data of SWAT-K for future period (2010-2099). Using the modeling results of the past (1992-2013) and the future period, the hydrological changes of each year were analyzed and the precipitation, runoff, evapotranspiration and recharge were increasing. Compared with the past, the change in the runoff was the largest (up to 50% increase) and the evapotranspiration was relatively small (up to 11% increase). Monthly results show that the amount of evapotranspiration and the amount of recharge are greatly increased as the amount of precipitation increases in August and September, while the amount of evapotranspiration decreases in the same period. January and December showed the opposite tendency. As a result of analyzing future water balance changes, the ratio of runoff, evapotranspiration, and recharge to rainfall did not change much, but compared to the past, the runoff rate increased up to 4.3% in the RCP 8.5 scenario, while the evapotranspiration rate decreased by up to 3.5%. Based on the results of other researchers and this study, it is expected that rainfall and runoff will increase gradually in the future under the assumption of present climate change scenarios. Especially summer precipitation and runoff are expected to increase. As a result, the amount of groundwater recharge in Jeju Island will increase.

• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.108-114
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• 2015

Single - and combined effects of a domestic freshwater bivalve Unio douglasiae (7.6~8.6 cm in shell length) and zooplankton Daphnia magna (1~2 mm in body size) were examined to understand whether they inhibit the growth of harmful cyanobacterial bloom (i.e. Microcystis aeruginosa) in a eutrophic lake. The experiments were triplicated with twelve glass aquaria (40 L in volume); three aquaria without mussel and zooplankton, served as a control, three zooplankton aquaria (Z, density=40 indiv. $L^{-1}$), three mussel aquaria (M, density=0.5 indiv. $L^{-1}$), and three mussel plus zooplankton aquarium (ZM, density=40 indiv.Z $L^{-1}$ plus 0.5 indiv.M/L), respectively. Algal growth inhibition (%) calculated as a difference in the concentration of chlorophyll-a (Chl-a) before and after treatment. Chl-a in all aquaria decreased with the time, while a greatest algal inhibition was seen in the ZM aquaria. After 24 hrs of incubation, Chl-a concentration at the mid-depth (ca. 15 cm) in ZM aquaria reduced by 90.8% of the control, while 63.2% and 79.8% in Z and M aquaria, respectively. Interestingly, during the same period, the surface Chl-a was diminished by 51.9% and 65.4% relative to the control in Z and ZM aquaria, while 27.4% of initial concentration decreased in M aquarium, respectively. These results suggest that 1) this domestic freshwater filter-feeding bivalve plays a significant role in the control of cyanobacterial bloom (M. aeruginosa), and 2) the combination with zooplankton and mussel has a synergistic effect to diminish them, compared to the single treatment of zooplankton and mussel.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.296-307
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• 2016

Ecological restoration is an eco-technology, which heals the nature damaged by human activity by imitating organization and function of the integrate nature and thereby provide an inhabitable space for diverse organisms. Such an ecological restoration has to be carried out by applying restoration plan prepared based on the results of diagnostic evaluation discussed in the diversified respects. This study aims to prepare an ecological restoration plan of the damaged forest ecosystem in Mt. Moodeung National Park. To arrive at the goal, first of all, we diagnosed quality of forest landscape established in Mt. Moodeung National Park based on natural (topography, climate, and distribution of vegetation) and artificial (land use, linear landscape element) factors. In addition, we evaluated the integrity of each zone divided by linear landscape element quantitatively based on geometric property and land use intensity. As the result of analysis, topography of Mt. Moodeung National Park tended to be depended on weathering property of parent rock and vegetation zones were divided to three vegetation zones. Based on land use pattern, deciduous broad-leaved forest, evergreen needle-leaved forest, and mixed forest occupied about 90% of Mt. Moodeung National Park. Mean score of forest landscape quality was shown in $69.86{\pm}11.41$. As a result, forest landscape elements in Mt. Moodeung National Park were influenced greatly by human activity and the degree was depended on topographic condition. This study suggested the synthetic restoration plan to improve ecological quality of Mt. Moodeung National Park based on the results of diagnostic evaluation.

• Journal of fish pathology
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• v.25 no.3
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• pp.257-262
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• 2012

A reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay was evaluated to monitor infectious hematopoietic necrosis virus (IHNV) from artificially infected rainbow trout Oncorhynchus mykiss. The cumulative mortalities of fish challenged with IHNV at $10^{6.5}\;TCID_{50}$/fish, $10^{5.5}\;TCID_{50}$/fish and $10^{4.5}\;TCID_{50}$/fish were 40%, 0% and 0%, respectively. Dead fish and survivors at 16 and 28 d post-challenge in each group were employed for IHNV detection by RT-LAMP assay and virus isolation using BF-2 cells. IHNV from $10^{4.3}$ to $10^{6.8}\;TCID_{50}/ml$ was isolated from all the dead fish and also detected in all of the examined dead fish by RT-LAMP assay. In survivors at 16 d, 60% (3/5 fish, $10^{2.8}-10^{5.05}\;TCID_{50}/ml$), 20% (1/5 fish, $10^{1.05}\;TCID_{50}/ml$) and 60% (3/5 fish, $10^{1.05}-10^{4.8}\;TCID_{50}/ml$) were found to be IHNV-positive by virus isolation in fish challenged with IHNV at $10^{6.5}\;TCID_{50}$/fish, $10^{5.5}\;TCID_{50}$/fish and $10^{4.5}\;TCID_{50}$/fish, respectively, while 20% (1/5 fish), 0% (0/5 fish) and 20% (1/5 fish) were IHNV-positive by RT-LAMP assay. No IHNV was detected in the survivors at 28 d and control fish. These results indicate that the RT-LAMP assay is useful for detection of IHNV in diseased fish although it is not enough to monitor virus in IHNV-survivors.

• Journal of fish pathology
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• v.23 no.2
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• pp.199-209
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• 2010

This study was aimed to investigate the effects in different immersion doses of garlic, Allium sativum, juice to modulate on the nonspecific immune responses of the olive flounder, Paralichthys olivaceus, artificially prechallenged with Streptococcus iniae BS10 and Edwardsiella tarda KE-1, respectively. The nonspecific immune responses of the tested fish were assessed in term of skin mucus lysozyme activity, the change of bacterial cell counts in organs, the number of lymphocytes and neutrophils in blood, and SOD activity. Almost groups of the prechallenged with either S. iniae BS10 or E. tarda KE-1 fish which had been immersed in garlic juice showed the enhanced skin mucus lysozyme activity, the number of lymphocytes and neutrophils in blood, and SOD activity in the kidney but the decreased the number of bacterial cell in surveyed organs. RPS in the group immersed in 0.25 g/L of garlic juice was much higher than in other immersed test groups. These results suggested that the garlic juice immersion can be effective on enhancement of the nonspecific immune responses and the protective ability of olive flounder to the artificial challenge with S. iniae BS10 and E. tarda KE-1.

• Journal of fish pathology
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• v.31 no.1
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• pp.41-48
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• 2018

The utility of Bacillus spp. organisms for reduction of dissolved hydrogen sulfide ($H_2S$) in white leg shrimp (Litopenaeus vannamei) culture was tested with different combinations of Bacillus spp. microorganisms: combination A (B. subtilis + B. licheniformis); combination B (B. licheniformis + B. amyloliquefaciens); combination C (B. subtilis + B. licheniformis + B. amyloliquefaciens). Of these 3 combinations, C was effective in few hours after addition whereas B needed longer time to be effective. The $H_2S-reducing$ effect of combination C was dependent on the amount of microorganisms added to $H_2S-containing$ test solution. Exposure of white leg shrimp to $H_2S$ at 8 mg/L for 7 days led to survival of 80% and 1 mg/L for 14 days it was 82.5%. The survival rate was 97.5% when combination C was simultaneously added to shrimp tanks during $H_2S$ exposure at 1 mg/L for 14 days. It was demonstrated that combination C microorganisms (B. subtilis + B. licheniformis + B. amyloliquefaciens) can reduce dissolved $H_2S$ concentrations, and this effect can be utilized to protect white leg shrimp from $H_2S$ toxicity.