• Journal of Korea Water Resources Association
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• v.47 no.5
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• pp.459-468
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• 2014

Groyne to control the direction and velocity of flow in rivers is generally installed for the purpose of protecting riverbanks or embankments from erosion caused by running water. In particular, as interest in river restoration and natural river improvement increases, groynes are proposed as a key hydraulic structure for local flow control and riparian habitat establishment. Groynes are installed mainly in groups rather than as individual structures. In case of groynes installed as a group, flow around the groynes change according to spacing in between the groynes. Therefore, groyne spacing is regarded as the most important factor in groyne design. This study aimed at examining changes of flows around and within the area of groynes that take place according to the spacing of groynes installed in order to propose the optimal spacing for upward groynes. To examine flow characteristics around groynes, this study looked at flows in main flow area and recirculation flow area separately. In main flow area, it examined the impact of flow velocity increasing as a result of conveyance reduction that is exerted on river bed stability in relation to changes in the maximum flow velocity according to installation spacing. As a factor causing impacts on scouring and sedimentation within the area of groynes, recirculation flow in the groyne area can lead problems concerning flow within the area and stability of embankment. As for recirculation area, an analysis was conducted on the scale of rotational flow and the flow around embankment that exerts impacts on stability of the embankment. In addition, a comparative analysis was carried with reference to changes of the central point of rotational flow that occur within the area of groynes. As a result of compositely examining the results, the appropriate installation spacing is proposed as min. four times-max. six times considering a decrease in flow velocity according to the installation of upward groynes, river bed stability and stability of embankments against counterflow within the area of groynes.

• Journal of Oral Medicine and Pain
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• v.34 no.4
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• pp.387-395
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• 2009

Nerve growth factor (NGF) and sensory neuropeptides are involved in the process of nociception at peripheral nerve fibers and wide spread in central nervous system. The aims of this study were to investigate NGF and sensory neuropeptides (substance P [SP] and calcitonin gene-related peptide [CGRP]) levels in human plasma and saliva, and the associations between these sensory neuropeptides levels and chronic orofacial pain symptoms. NGF, SP, and CGRP levels in plasma and resting whole saliva samples collected from 67 orofacial pain patients (joint pain, dental or periodontal pain, mucosal pain) and 36 pain free control subjects were measured by enzyme immunoassay. The characteristic pain intensity of each subject was measured using the Graded Chronic Pain Scale and the flow rate of resting whole saliva was measured. Joint pain patients group showed significantly higher plasma NGF level compared to each of dental pain patients (p<0.01), mucosal pain patients (p<0.01), and control group (p<0.01). Plasma NGF level of dental pain patients group was significantly higher than that of control group (p<0.01). Saliva SP level of dental pain patients group (p<0.05) and saliva CGRP level of mucosal pain group (p<0.05) were significantly higher than that of control group. Plasma and saliva SP levels of joint pain patients was significantly associated with pain intensity (plasma: standardized coefficient=0.599, p<0.01, saliva: standardized coefficient=0.504, p=0.05). In dental pain patients group, plasma SP (standardized coefficient=0.559, p<0.01), saliva SP (standardized coefficient=0.520, p<0.01) and saliva CGRP (standardized coefficient=0.599, p<0.01) levels were significantly associated with age. In mucosal pain patients group, plasma SP (standardized coefficient=0.495, p<0.05), saliva SP (standardized coefficient=0.500, p<0.05), and saliva CGRP (standardized coefficient=0.717, p<0.01) levels were significantly associated with age. NGF and neuropeptides may play a role in the maintenance of various orofacial pain symptoms. The examination of those levels in plasma and saliva helps understanding the mechanism of orofacial pain, and furthermore, can be applied to the diagnosis and therapy of orofacial pain.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.424-434
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• 2009

Statement of problem: Problems such as loosening and fractures of retained screws and fracture of implant fixture have been frequently reported in implant prosthesis. Purpose: Implant has weak mechanical properties against lateral loading compared to vertical occlusal loading, and therefore, stress analysis of implant fixture depending on its material and geometric features is needed. Material and methods: Total 28 of external hexed implants were divided into 7 of 4 groups; Group A (3i, FULL $OSSEOTITE^{(R)}$Implant), Group B (Nobelbiocare, $Br{\aa}nemark$ $System^{(R)}$Mk III Groovy RP), Group C (Neobiotec, $SinusQuick^{TM}$ EB), Group D (Osstem, US-II). The type III gold alloy prostheses were fabricated using adequate UCLA gold abutments. Fixture, abutment screw, and abutment were connected and cross-sectioned vertically. Hardness test was conducted using MXT-$\alpha$. For fatigue fracture test, with MTS 810, the specimens were loaded to the extent of 60-600 N until fracture occurred. The fracture pattern of abutment screw and fixture was observed under scanning electron microscope. A comparative study of stress distribution and fracture area of abutment screw and fixture was carried out through finite element analysis Results: 1. In Vicker's hardness test of abutment screw, the highest value was measured in group A and lowest value was measured in group D. 2. In all implant groups, implant fixture fractures occurred mainly at the 3-4th fixture thread valley where tensile stress was concentrated. When the fatigue life was compared, significant difference was found between the group A, B, C and D (P<.05). 3. The fracture patterns of group B and group D showed complex failure type, a fracture behavior including transverse and longitudinal failure patterns in both fixture and abutment screw. In Group A and C, however, the transverse failure of fixture was only observed. 4. The finite element analysis infers that a fatigue crack started at the fixture surface. Conclusion: The maximum tensile stress was found in the implant fixture at the level of cortical bone. The fatigue fracture occurred when the dead space of implant fixture coincides with jig surface where the maximum tensile stress was generated. To increase implant durability, prevention of surrounding bone resorption is important. However, if the bone resorption progresses to the level of dead space, the frequency of implant fracture would increase. Thus, proper management is needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.343-349
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• 2010

The liver is the major target of ethanol toxicity and oxidative stress plays a role in development of alcoholic liver disease. This study was performed to investigate the effects of green tea extracts (GTE) on acute ethanol-induced hepatotoxicity in rats. Experimental animals were divided into 4 groups, control, GTE, ethanol, and GTE+ethanol treatment, with 5 rats in each group. Ethanol (6 g/kg body weight (BW)) and GTE (200 mg/kg BW) were treated by gavage. At 1 hour, 3 hours and 20 days (6 g/kg BW every 2 days for total 10 doses) after ethanol and/or GTE treatments, animals were killed; hepatic tumor necrosis factor-alpha (TNF-$\alpha$) and glutathione level, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), hepatic antioxidant enzymes (SOD, CAT, GPx) activities and hepatic thiobarbituric acid reactive substances (TBARS) were measured. At 1 hour and 3 hours, hepatic TNF-$\alpha$ levels were increased significantly in ethanol group and ethanol+GTE group but that levels was significantly lower in ethanol+GTE group compared with ethanol group. Hepatic glutathione level was decreased by ethanol treatment but GTE prevented the ethanol-induced glutathione decrement. The levels of liver marker enzymes (AST, ALT), liver antioxidant enzymes (SOD, CAT, GPx) and lipid peroxidation marker (TBARS) were not changed in rats of 1 and 3 hours after ethanol treatment. After 20 days, GTE decreased the changes of liver marker enzymes (AST, ALT) activities and TBARS level by ethanol. This study shows that GTE beneficially modulates TNF-$\alpha$ and glutathione levels in liver of ethanol administered rats. The GTE supplementation could be beneficial to liver by decreasing early changes of biomarkers of liver damage caused by ethanol.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.531-539
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• 2019

This study assessed the vitality of Carpinus laxiflora seeds stored for more than 15 years in order to discover optimal pre-treatment conditions for removingthe causes of seed dormancy and improving revitalization rate. Seeds were collected in October 2000 and stored at -18℃ for 16 years. Experiments to assess the revitalization ability of the seeds were performed under the following conditions: a controlled environment; in warm stratification (30 days at 23℃); in cold stratification (30 days at 4℃ andfor 30, 45, 60, and 120 days); gibberellin (GA₃) treatment (24 hours per day in GA₃ solutions of 100, 500, 1000, 2000, and 3000 mg·L^-1); and both cold stratification and GA₃ treatment (30 days at 4℃, then in a GA₃ solution of 100, 500, and 1000 mg·L^-1 for 2 hours). The average germination percentage(GP) of untreated seeds was 2%, and the average GP of warm-stratification seeds was 10%. Cold-stratification seeds had the highest GP at 81% for the 45-day process, while the 120-day cold-stratification seeds had the lowest GP at 67.3%. The average GP of seeds treated with GA₃ ranged from 77% (100 mg·L^-1) to 99% (1000 mg·L^-1), indicatingsignificant differences between the treatment concentrations. The treatment effect of GA₃ was highest at 500 mg·L^-1 and 1000 mg·L^-1, and lowest at 100 mg·L^-1. The average GP of seeds treated with GA₃ following cold stratification was 68%, which was lower than the cold stratification-only (73.2%) and GA₃-only (88.4%) treatments. A comprehensive comparison of the seed germination characteristics according to the four treatments determined that a GA₃ 500 mg·L^-1 pre-treatment, with the highest average GP, was ideally suited to the revitalization of long-term stored C. laxiflora seeds. Consequently, C. laxiflora stored at -18℃ for 16 years indicated strong vitality and could be regenerated by proper pre-treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1843-1851
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• 2014

This study evaluated the quality characteristics and antioxidant activities of barley Doenjang (soybean paste) containing various contents (4, 12, and 20%) of kelp extracts. After 60 days of fermentation, pH, acidity, and viscosity of Doenjang were 5.80~6.86, 0.57~1.87%, and 4,913.3~9,333.3 cps, respectively, showing significant differences according to content of kelp extracts. Amino-type nitrogen contents was 902.60~921.90 mg%. For color values, L and b values increased significantly (P<0.001), whereas a value decreased slightly according to kelp extracts. DPPH radical scavenging effect ($IC_{50}$) for butylated hydroxyanisole ranged from 10.28 mg/mL to 23.23 mg/mL. DPPH radical scavenging effects of control was highest among the samples. The total polyphenol and flavonoid contents were 12.72~6.37 mg tannic acid equivalence/g, and $0.98{\sim}1.56{\mu}g$ rutin equivalence/g, respectively. Initial counts of total bacteria and lactic acid bacteria were 7.20~7.57 log CFU/g, and 4.20~4.71 log CFU/g respectively, showing significant difference according treatment and fermentation (P<0.05). In the sensory evaluation, 20% kelp extract Doenjang (5.6) showed higher overall acceptability than other samples (6.5) (P<0.01). Especially, umami taste (6.1) and texture (6.4) of 20% kelp extract Doenjang were higher than those of control (P<0.05). These results suggest that Doenjang containing kelp extracts, will be good for industrial fields.

• Journal of Gastric Cancer
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• v.6 no.1
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• pp.31-35
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• 2006

Purpose: A primary adenosquamous carcinoma of the stomach is relatively rare, accounting for only about 0.5% of all gastric cancers. However, its histopathologic characteristics are still unclear, and the most appropriate form of therapy has not been established yet. Materials and Methods: We retrospectively reviewed the clinicopathologic features of 8 patients with pathologically confirmed primary adenosquamous carcinomas out of 8,268 patients who underwent gastric cancer surgery at Samsung Medical Center between September 1994 and December 2004. Results: The median age of the 8 patients was 49 ($41{\sim}69$) years, and the male : female ratio was 5 : 3. In 3 patients, the tumor was located at the mid body of the stomach, and in 5 patients, at the lower body or antrum. The tumor sizes were $2.5{\sim}8cm$. Seven patients showed metastases to the regional lymph nodes. The UICC stage distribution were: 5 stage II, 2 stage III, and 1 stage IV. In the stage IV patient, a palliative gastrojejunostomy was performed, and he died 5 months after surgery. Of the 7 patients who underwent a radical gastrectomy and adjuvant chemotheratpy, the median survival was 34 ($12{\sim}66$) months, 2 patients died of cancer recurrence, and 4 patients are being followed up without evidence of recurrence. Conclusion: As for an adenocarcinoma of the stomach, a radical gastrectomy including regional lymph node dissection and postoperative adjuvant therapy should be performed for appropriate treatment of an adenosquamous carcinoma of the stomach.

• Tuberculosis and Respiratory Diseases
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• v.56 no.4
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• pp.393-404
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• 2004

Background : Nucleic acid hybridization has become an essential technique in the development of our understanding of gene structure and function. The quantitative analysis of hybridization has been used in the measurement of genome complexity and gene copy number. The filter hybridization assay is rapid, sensitive and can be used to measure RNAs complementary to any cloned DNA sequence. Methods : The authors assessed the accuracy, linearity, correlation coefficient and specificity of the hybridization depending on the added dose(0, 1, 5, and $10{\mu}g$) of non-specific rat spleen RNA to hybridization of surfactant protein A mRNA. Filter hybridization assays were used to obtain the equation of standard curve and thereby to quantitate the mRNA quantitation. Results : 1. Standard curve equation of filter hybridization assay between counts per minute (X) and spleen RNA input (Y) was Y=0.13X-19.35. Correlation coefficient was 0.98. 2. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) was Y=0.00066X-0.046. Correlation coefficient was 0.99. 3. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) after the addition of $1{\mu}g$ spleen RNA was Y=0.00056X-0.051. Correlation coefficient was 0.99. 4. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) after the addition of $5{\mu}g$ spleen RNA was Y=0.00065X-0.088. Correlation coefficient was 0.99. 5. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) after the addition of $10{\mu}g$ spleen RNA was Y=0.00051X-0.10. Correlation coefficient was 0.99. Conclusions : Comparison of cpm/filter in a linear range allowed accurate and reproducible estimation of surfactant protein A mRNA copy number irrespective of the addition dosage of non-specific rat spleen RNA over the range $0-10{\mu}g$.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.488-495
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• 2005

This study was conducted to understand the influences of forest structure on throughfall, stemflow and interception loss. The study plots included the natural old-growth deciduous, Pinus koraiensis and Abies holophylla forests in Gwangneung and the rehabilitated young mixed forest in Yangju, Gyeonggido. The Pinus koraiensis and Abies hotophylla had been planted in 1976. The rehabilitated young mixed forest had been established to control erosion in 1974. Total and net rainfall were monitored from March, 2003 to October, 2004. Tipping bucket rain gauge recorded total rainfall. Throughfall and stemflow were measured by custom-made tipping bucket and CR10X data logger at each $10m{\times}10m$ plots at intervals of 30 minutes. Interception loss in the Pinus koraiensis plot were most as 37.2% of total rainfall and least as 22.6% in the rehabilitated young mixed forest. Stemflow in the rehabilitated young mixed forest was 10.7% of total rainfall and stemflow in the Pinus koraiensis plot was 2.4%. The average throughfall ratio ranged from 66% to 77% depending on the canopy coverage. The relationship of stemflow and total rainfall represented in a linear regression equation though the variation of data was large. The ratio of stemflow-conversion was 2% of total rainfall in the Pinus koraiensis plot and 12% in the rehabilitated young mixed forest, respectively. The stem storage of the natural old-growth deciduous was the largest of 0.21 mm whereas that of the Pinus koraiensis plot was the least of 0.003 mm. A deciduous forest produced stemflow more than a coniferous forest due to a smooth bark and steeply angled branches. Interception loss of all study plots increased linearly as total rainfall increased. The distribution of interception loss data related in total rainfall became wider in a deciduous forest than a coniferous. It resulted from seasonality of leaf area index in a deciduous forest. As considered above results, it was confirmed that there were great differences of throughfall, stemflow and interception loss depending on forest stand structures. The simulation model for predicting interception loss must have parameters such as forest stand characteristics and LAI in order to describe the influence of forest structure on interception loss.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.402-409
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• 2005

This study was undertaken to compare and estimate the severity of pitch canker of individual trees of Pinus rigida and Pinus rigida ${\times}$ P. taeda in two seed orchards in Jeju island, in which the orchards have been damaged by the pitch canker for seven years. Wind-pollinated two-year-old seedlings of P. rigida and P. rigida ${\times}$ P. taeda, in which the seedlings of P. rigida ${\times}$ P. taeda were from seeds of phenotypically selected, uninfected(but untested) trees, were inoculated with the pathogenic fungus, Fusarium circinatum, isolated from P. rigida and P. thunbergii. The virulence of the isolates was also identified. Statistically significant difference was found in 'stem cankers'(SC; ${\chi}^2=7.76$, P=0.05) among 4 plantations of P. rigida ${\times}$ P. taeda of two seed orchards. P. rigida was higher in 'top kill' (TK) and 'branch tip symptoms' (BT) than those of P. rigida ${\times}$ P. taeda. In artificial inoculation tests, mortality of the seedlings from the resistant candidates was 14% higher than that of the seedlings from the susceptible candidates. This result may becaused by unknown pollen trees and/or candidate tree selection based only on phenotype. Two of five fungal isolates, C-6-L(9) and C-6-L(19), showed significantly higher mortality (68% and 60%, respectively) than others, suggesting that these isolates can be used as virulent isolates for a mass artificial inoculation. Resistance candidate seedlings that were selected from this study can be utilized as useful materials for fundamental studies of genetics and biochemistry to breed resistance varieties to pitch canker.