• Korean Journal of Soil Science and Fertilizer
• /
• v.11 no.3
• /
• pp.145-160
• /
• 1979

The effects of organic material application on soil physical properties were reviewed in relation to soil productivity. The organic matter contents and soil physical properties of the cultivated land in Korea were summarized and the effects of organic matter were compared in terms of land uses and soil types. Soil physical properties related to crop yield potential, such as soil aggregation, permeability, water holding capacity, erodibility, and compactibility, were used in evaluating the effects of organic materials as a soil physical amendment. The benefical effects of organic matter addition on soil physical conditions include (1) better aeration and increased infiltration in silty and clayey soils, (2) increased water holding capacity and moisture availability in sandy soils, (3) decreased soil erodibility, and (4) increased resistance to compaction. It is, therefore, concluded that continuous application of organic materials could greatly improve the various soil physical properties and favor the growth and yield of crops. A high rate of organic matter addition could contribute to reducing not only the soil erosion on sloping land, but also the possible detrimental effect of farm mechanization. In general, the effects of organic matter on soil physical improvement were estimated to be much higher in upland than in paddy. Organic matter would have a more pronounced effect on low productive lands such as heavy clayey or sandy soils and newly reclaimed soil. The optimum level of soil organic matter content was estimated to be about 3.0 to 3.5% for the best soil physical condition. Since the organic matter contents of the cultivated lands in Korea are much lower than optimum level, it would be desiable to use more organic materials to soil for the increase of soil productivity, continuation of stabilized high productivity and soil erosion control.

• Clinical and Experimental Pediatrics
• /
• v.46 no.2
• /
• pp.143-153
• /
• 2003

Purpose : Infection with Shiga-like toxin (SLT)-producing Escherichia coli, an emerging human pathogen found particularly in young children under 5 years of age, causes a spectrum of illnesses with high morbidity and mortality, ranging from diarrhea to hemorrhagic colitis and hemolytic uremic syndrome. Host mediators play an important role in the pathogenesis of SLT-I toxicity. The experiments described here were designed to investigate the effect of SLT-I on TNF-${\alpha}$ production and to understand the effect of TNF-${\alpha}$ on GB3 expression. We also further examine the relationship between the Gb3 level and the differential susceptibility of cells to the cytotoxic action of SLT-I. Methods : The effect of purified SLT-1 from E. coli O157 : H7 (ATCC 43890) on tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) production in Raw264.7 cells was investigated. Many mediators regulate endothelial cell membrane expression of the glycolipid globotriaosyleramide (Gb3), which serves as the toxin receptor, suggesting that the host response to the toxin or other bacterial products may contribute to pathogenesis by regulating target cell sensitivity to the toxins. Therefore, the relationships between Gb3 expression and cytotoxicity against SLT-I on three types of cells were evaluated. Results : Detectable levels of TNF-${\alpha}$ were produced as early as six hours after induction and continued to increase during 48 hours by SLT-I. It was also found that Vero cells and dendritic cells (DC2.4 cells) expressed high levels of Gb3, 83% and 68%, respectively, and that Raw264.7 cells had a low level of Gb3 (29%) and appeared refractory to cytotoxicity against SLT-I. Vero cells and DC2.4 cells expressing high levels of Gb3 were highly susceptible to SLT-I. Furthermore, macrophages showed a resistance to SLT-I cytotoxicity, despite the fact that Gb3 expression was enhanced. Conclusion : These results strongly suggest that the expression of Gb3 is necessary but not sufficient to confer sensitivity of macrophages to SLT-I and further underpin the important role of SLT-I and its Gb3 receptors in the pathogenesis of E. coli O157 infection.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.3
• /
• pp.574-582
• /
• 1998

Background: Bronchofiberscopy is a procedure with a chance of airway irritation and it may cause pathophysiologic changes of respiratory system. So we tried to evaluate the influence of bronchofibercopy on $O_2$ saturation, ABGA and PIT by patient's basal status and procedure type. Method: $O_2$ saturation was measured every 1 minute from the left index finger tip with percutaneous oximetry. ABGA was done before and right after the bronchofiberscopy and PIT was done before and within 10 minutes after the bronchofiberscopy. Results: The mean time for bronchofiberscopy procedure was 14.5mim and $SaO_2$ maximally fall to 89.0 below 8% of the baseline after mean time of 8.4min, which was recovered at the end of the procedure. $SaO_2$ change amount was 8.4 % on Non-$O_2$ supply group, which was lower compared to 6.4 % of the $O_2$-supply group without statistically significance. Biopsy Group and BAL group showed more $SaO_2$ fall than washing only group. The level of $PaO_2$ and FEV1 of the patient didn't influence significantly on $SaO_2$ fall during the procedure. ABGA taken before and after the bronchofiberscopy showed mild fall of $PaO_2$ and mild rise of $PaCO_2$. Whereas PFT showed decrease of FEV1(P<0.05) and increase of RV without changes in airway resistance and pulmonary diffusion capacity. Comparing before and after the bronchofiberscopy, the washing group showed no significant changes on PIT, while the biopsy group and the BAL group showed increase of RV & decrease of $FEV_1$ after the bronchofiberscopy. BAL group showed more changing tendency rather than biopsy group although not statistically significant. Conclusion: Bronchofiberscopy is considered as a relatively safe procedure, but it would be better to be done with $O_2$ supply especially in the patient with low $PaO_2$ and in the case of biopsy and BAL.

• Journal of the Korean Electrochemical Society
• /
• v.4 no.2
• /
• pp.58-64
• /
• 2001

YSZ ($8mol\%$ yttria-stabilized zirconia)-modified LSM $(La_{0.85}Sr_{0.15}MnO_3)$ composite cathodes were fabricated by formation of YSZ film on triple phase boundary (TPB) of LSM/YSZ/gas. The YSZ coating film greatly enlarged electrochemical reaction sites from the increase of additional TPB. The composite cathode was formed on thin YSZ electrolyte (about 30 Um thickness) supported on an anode and then I-V characterization and AC impedance analyses were performed at temperature between $700^{\circ}C\;and\;800^{\circ}C$. As results of the impedance analysis on the cell at $800^{\circ}C$ with humidified hydrogen as the fuel and air as the oxidant, R1 around the frequency of 1000 Hz represents the anode Polarization. R2 around the frequency of 100Hz indicates the cathode polarization, and R3 below the frequency of 10 Hz is the resistance of gas phase diffusion through the anode. The cell with the composite cathode produced power density of $0.55\;W/cm^2\;and\;1W/cm^2$ at air and oxygen atmosphere, respectively. The I-V curve could be divided into two parts showing distinctive behavior. At low current density region (part I) the performance decreased steeply and at high current density region (part II) the performance decreased gradually. At the part I the performance decrease was especially resulted from the large cathode polarization, while at the part H the performance decrease related to the electrolyte polarization.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.10
• /
• pp.480-489
• /
• 2017

Blood flow restriction(BFR) exercise is defined as low intensity and short term exercise using pneumatic pressure belts at the top of limbs, which affects the physiological functions of the body. The purpose of this study was to investigate the effects of walking exercise with BFR on inflammatory index, isokinetic muscle function, and thigh circumference in obese women. Eleven obese women(> BMI $25kg/m^2$ & > body fat 30%) wore pneumatic pressure belts on both femurs and performed walking exercise twice per day, 3 days/wk for 4 weeks (walking 2 min; resting 1 min). Data analysis was carried out using paired t-test. Body weight, BMI, and body fat significantly decreased after exercise(p<.05), and right thigh circumference significantly decreased(p<.05). The concentration of plasma IL-6 significantly increased(p<.05) after exercise. TNF-${\alpha}$ level was not statistically different but tended to slightly increase. CRP slightly decreased, although it did not reach statistical significance after exercise. Muscle strength significantly increased in the $60^{\circ}/sec$ of right/left side extension, left side flexion, and $180^{\circ}/sec$ of left side extension after training(p<.05). These results suggest that 4 weeks of blood flow restriction walking exercise has positive effects on inflammatory index and isokinetic muscle function. Therefore, we consider that blood flow restriction exercise can be used for treatment of obesity, related chronic diseases, and metabolic syndrome. Further, blood flow restriction exercise for a short time has similar effects as a high intensity resistance program.

• Tuberculosis and Respiratory Diseases
• /
• v.50 no.1
• /
• pp.12-28
• /
• 2001

Background and Object : Immunostimulatory CpG-oligodeoxynucleotides (ISS CpG-ODN) up-regulate the $T_{H1}$-type immune response and down-regulate the $T_{H2}$-type response. This study was performed to investigate the immune response changes resulting from ISS CpG-ODN on bronchial hyperresponsiveness, eosinophilic inflammation and mucus hypersecretion in rat asthma. Materials and Methods : 10 normal controls(NC) and 26 asthmatic rats, which were generated by ovalbumin(OVA) sensitization and challenge, were studied. The asthmatic rats were randomized into 11 asthma controls(AC) and 15 in the asthma-CpG treatment group(CpG). The CpG group was administered ISS CpG-ODN intramuscularly and the AC group was administered a placebo(0.9% NaCl) on day 15 and 20. After CpG-ODN or placebo administration, we measured the IFN-${\gamma}$($T_{H1}$-type cytokine) and IL-4($T_{H2}$-type cytokine) levels in the bronchoalveolar lavage fluid(BALF), the specific airway resistance(sRaw), eosinophilic fraction in BALF, eosinophilic infiltration, goblet cell dysplasia and MUC5AC gene expression in the lung tissue. Results : In the BALF of the CpG group, the IFN-${\gamma}$ concentration was significantly high and the IL-4 concentration was significantly low when compared with the AC group. Both the sRaw and eosinophilic fraction, and infiltration into the BALF and lung tissue significantly lower in the CpG group when compared with the AC group. However, little difference in goblet cell dysplasia and MUC5AC gene expression was observed between the CpG group and the AC group. Conclusion : ISS CpG-ODN decreases bronchial hyperresponsiveness and eosinophilic inflammation in the rat asthma model through the up-regulation of the $T_{H1}$-type immune response with the down-regulation of the $T_{H2}$-type response. However, the effect of these immune response changes on mucus hypersecretion was is not remarkable in this study.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.36 no.2
• /
• pp.21-29
• /
• 2018

This study was wanted to select a value evaluation item to maintain the authenticity of the Planting Landscape in Hahoe and Yangdong villages. Above all, after checking the suitability of the 43 selected items by the Focus Group Interview, the weight was calculated in the Analytic Hierarchy Process expert questionnaire to establish the importance of the indicators for the development of the assessment items. The expert analysis analyzed the importance of 2 sections, 6 divisions and 11 detailed categories, and summarized the results of the study as follows : First, the comparative importance of each category and selection of the assessment items for the stabilization of the Planting Landscape of Hahoe and Yangdong indicated that cultural values are more important than biological values. In particular, details of the biological values of trees were derived with relatively low estimates, except for the specific characteristics of species and items of type of tree. Second, as a result of verification of the suitability of the 43 items selected by the Focus Group Interview, the source diameter, the collection width, reception, flushing, supersonality, records, memorials, 11 items were selected, Third, the results of the importance evaluation of the value properties for maintaining the resistance of vegetation through the Analytic Hierarchy Process were : specific in biological values (0.187), steady (0.094), and water pipe width (2007). There was relatively little difference in the highest weights, the width of the pipe except for the lowest value received, and the source diameter flushing. Fourth, the results of an evaluation of the importance of a value property aimed at historical values were whether or not the cultural asset was designated (0.134), the record value (0.092), the time (0.088), and the monument (0.063). In terms of the importance of evaluating the historical values of Planting sites consisting of Hahoe and Yangdong, the importance of designation of cultural properties was considered to be relative to the maintenance of the Planting Landscape including culture and history. Based on the assessment items and weighted values of the Planting Landscape of Yangdong Village and the World Cultural Heritage below and below, this study's Analytic Hierarchy Process can be applied to actual criteria for the assessment of the authenticity of trees in the village. Based on the assessment items and weighted values of the Planting Landscape in Hahoe and Yangdong villages, a follow-up study on the assessment standards for the authenticity of trees in the village will be left as a future task.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.8 no.1
• /
• pp.1-9
• /
• 2006

Regardless of the recent observed warmer winters in Korea, more freeze injuries and associated economic losses are reported in fruit industry than ever before. Existing freeze-frost forecasting systems employ only daily minimum temperature for judging the potential damage on dormant flowering buds but cannot accommodate potential biological responses such as short-term acclimation of plants to severe weather episodes as well as annual variation in climate. We introduce 'dormancy depth', in addition to daily minimum temperature, as a complementary criterion for judging the potential damage of freezing temperatures on dormant flowering buds of grape vines. Dormancy depth can be estimated by a phonology model driven by daily maximum and minimum temperature and is expected to make a reasonable proxy for physiological tolerance of buds to low temperature. Dormancy depth at a selected site was estimated for a climatological normal year by this model, and we found a close similarity in time course change pattern between the estimated dormancy depth and the known cold tolerance of fruit trees. Inter-annual and spatial variation in dormancy depth were identified by this method, showing the feasibility of using dormancy depth as a proxy indicator for tolerance to low temperature during the winter season. The model was applied to 10 vineyards which were recently damaged by a cold spell, and a temperature-dormancy depth-freeze injury relationship was formulated into an exponential-saturation model which can be used for judging freeze risk under a given set of temperature and dormancy depth. Based on this model and the expected lowest temperature with a 10-year recurrence interval, a freeze risk probability map was produced for Hwaseong County, Korea. The results seemed to explain why the vineyards in the warmer part of Hwaseong County have been hit by more freeBe damage than those in the cooler part of the county. A dormancy depth-minimum temperature dual engine freeze warning system was designed for vineyards in major production counties in Korea by combining the site-specific dormancy depth and minimum temperature forecasts with the freeze risk model. In this system, daily accumulation of thermal time since last fall leads to the dormancy state (depth) for today. The regional minimum temperature forecast for tomorrow by the Korea Meteorological Administration is converted to the site specific forecast at a 30m resolution. These data are input to the freeze risk model and the percent damage probability is calculated for each grid cell and mapped for the entire county. Similar approaches may be used to develop freeze warning systems for other deciduous fruit trees.

• The Korean Journal of Nuclear Medicine
• /
• v.4 no.2
• /
• pp.11-27
• /
• 1970

Cardiac output, plasma volume and renal plasma flow were determined to evaluate hemodynamic changes in 29 patients with cirrhosis of the liver. The results obtained were as follows. 1. The mean plasma volume was 3793+895ml and it was significantly higher than the normal controls. The mean blood volume ($5266{\pm}1222ml$) and blood volume per kg body weight ($95.7{\pm}23.41ml$) were also increased significantly. The mean plasma volume per kg body weight ($69.1{\pm}19.1ml$) showed increased tendency and the mean difference between blood volume and plasma volume per kg body weight ($26.4{\pm}7.05ml$) was in lower limit of normal range. 2. The mean cardiac output was $7708{\pm}2652ml/min$ and it was significantly increased. The mean cardiac index ($4924{\pm}1998ml/min/M^2$), stroke volume ($96.2{\pm}34.2ml/beat$), stroke index ($62.3{\pm}27.34ml/M^2$) and fractional cardiac index ($1.54{\pm}0.577$) were also increased significantly. The mean total -peripheral resistance was $1664{\pm}753.8\;dynes\;sec\;cm^{-5}M^2$ and it was significantly lower than the normal controls. 3. The mean renal plasma flow was $537{\pm}146.8ml/min/1.73M^2$ and it was normal to decreased tendency. The mean endogenous creatinine clearance ($66.7{\pm}23.0ml/min/1.73M^2$) was significantly decreased. Filtration fraction was variable, but it was slightly lower than normal in most cases. The mean renal fraction of cardiac output ($11.4{\pm}6.27%$) was relatively decreased. 4. Although renal plasma flow was normal or decreased in general, it was definitely diminished in patients with creatinine clearance less than $60ml/min/1.73M^2$, resistant ascites, and signs of azotemia (elevated BUN and serum creatinine). 5. Diminished glomrular filtration rate with low filtration fraction and decreased renal fraction of cardiac output observed strongly supported increased renal afferent arteriolar resistance. 6. Renal circulatory impairment preceded azotemia or oroliguria in cirrhosis. 7. Clinical findigns and liver function were not correlated with hemodynamic changes, except for esophageal varices associated with high cardiac output obsedved. 8. No definite correlation of renal hemodynamics with plasma volume or cardiac output was found.

• The Korean Journal of Nuclear Medicine
• /
• v.35 no.3
• /
• pp.168-184
• /
• 2001

Purpose: KR-30035 (KR), a new MDR reversing agent, has been found to produce a similar degree of increased Tc-99m MIBI uptake in cultured tumor cells over-expressing mdr1 mRNA compared to verapamil (VP), with less cardiovascular effects. We assessed the MDR-reversing ability of KR in vivo, and effects of various doses of KR on MIBI uptake un nude mice hearing P-glycoprotein (P-gp) positive (+) and P-gp negative (-) human tumor xenografts. Methods: P-gp (+) HCT15/CL02 colorectal and P-gp (-) A549 non-small cell cancer cells were inoculated in each flank of 120 nude mice (20 mice ${\times}$ 6 groups). Group 1 (Gr1) mice received 10mg/kg KR i.p. 3 times $({\times}3)$; Gr2, 10mg/kg VP i.p. ${\times}3$; Gr3, 10mg/kg KR i.p. ${\times}2$ + 25mg/kg KR i.p. ${\times}1$; Gr4, 10mg/kg KR i.p. ${\times}2$ + 50mg/kg i.p. ${\times}1$; Gr5, 10mg/kg KR i.p. ${\times}2$ + 25mg/kg KR i.v. ${\times}1$, GrC, controls. The mice were then injected with Tc-99m MIBI and sacrificed after 10 min, 30 min, 90 min and 240 min. Tumor uptake of MIBI (TU) in each group was compared. Results: TU in P-gp (+) and (-) tumors were both higher in Gr1 than Gr2. Washout rate between the 10 min and 4 hours was lower in Gr5 of P-gp (+) cell(0.93) than the control. Percentage increases in TU were higher in P-gp (+) than P-gp (-) tumors with all KR doses. Pgp (+) TU were highest at 10 mon (173% of GrC) and persisted up to 240 min (144%) in Gr3. Larger doses of KR resulted in a lesser degree of increase in P-gp (+) TU at 10 min (130% in Gr4 and 117% un Gr5) and 30 min (178%, 129%), but TU increased by time up to 240 min (177%, 196%). Heart and lung uptakes were markedly increased in Gr4 and Gr5 at 10 and 30 min, likely due to cardiovascular effects. No mice died. Conclusion: These data further suggest that KR that has significantly lower cardiovascular toxicity than verapamil can be used as an active inhibitor of MDR. Even a relatively low dose of KR significantly increased Tc-99m MIBI uptake in P-gp (+) tumors in vivo.