• Journal of Life Science
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• v.29 no.5
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• pp.509-513
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• 2019

The Beer-Lambert law states that absorbance is proportional to the concentration of a solute in a solution at a given wavelength. This linearity works for an ideal or a 'sufficiently diluted' solution, so this linearity is often used as a criterion for the fidelity of the absorbance value measured. In this study, we used a chlorophyll (Chl) solution, isolated from rice leaves with 80% acetone to test the use of the Chl a/b ratio as an additional criterion for checking the fidelity of measured values using four different absorption spectrophotometers: Cary4E, UV-1650PC, Versamax (a microplate reader), and NanoDrop 1,000(which can handle a $4{\mu}l$ aliquot). We used Chl solutions of varying concentrations from $0.2{\mu}g/ml$ to $200{\mu}g/ml$ to measure absorbance values at 645 nm and 663 nm and checked the linearity first. The results indicated that the range of Chl concentrations that we can rely on based on the linearity was similar to the range in which the calculated Chl concentrations based on the measured absorbance values agreed with the known concentrations. However, some border cases or cases with very low Chl concentrations inside the fidelity range of Chl concentrations did not agree with the criterion that the Chl a/b ratio should not change after dilution of the Chl in the solution. These results suggest that the Chl a/b ratio is a better criterion for the reliability of the absorbance values measured for the determination of chlorophyll concentration than the criterion based on the linearity suggested by the Beer-Lambert law.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.2
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• pp.115-123
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• 2022

This study was performed to determine carbon (C) storage of urban parks [Hadae park (established year: 1977), Songlim park (established year: 1990), Pyeonggeo park (1992), Chojeon park (2005)] in Jinju-si, Gyeongsangnam-do. The soil at 0-30 cm depth was collected to measure soil C concentration. Bulk density in all soil depths was not significantly different among the four parks, whereas coarse fragments (>2 mm) were significantly higher in the Chojeon park than in the Pyeonggeo park. Soil pH and electrical conductivity were highest in Chojeon park among four parks. Soil C concentrations in all soil depths were significantly higher in the Hadae park established in 19 77 compared with the other parks established since 1990. Mean soil C concentration at 0-30 cm was the highest in the Hadae park (1.04%), followed by the Chojeon park (0.87%), the Songlim park (0.75%), and the Pyeonggeo park (0.57%). Soil C storage at 0-10 cm was not significantly different among the four urban parks, whereas soil C storage at 10-20 cm and 20-30 cm was higher in the Hadae parks than in the other parks. Total soil C storage was significantly higher in the Hadae park (28,425 kg C ha^-1) than in the Pyeonggeo park (15,622 kg C ha^-1). Mean soil C concentration and C storage were positively correlated with silt content and negatively correlated with sand content. The results suggest that soil C storage of urban parks in Jinju-si might be related to the established period of parks and silt contents.

• Journal of the Society of Disaster Information
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• v.19 no.2
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• pp.344-351
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• 2023

Purpose: This study aimed to evaluate the effectiveness of a dielectric barrier discharge (DBD) plasma module for sterilizing airborne bacteria in indoor spaces and measure the concentration of ozone generated during plasma discharge. Method: The DBD plasma module was installed in a 76m³ space, and air samples were collected under various discharge times to compare the reduction of airborne bacteria. Result: The results showed a significant decrease in airborne bacteria, ranging from 92.057% to 99.999%, with an average ozone concentration of 0.04 ppm, below the reference value. Conclusion: The study suggests that plasma discharge can be used as a means of preventing the spread of airborne bacteria and viruses, while ensuring safety for human exposure.

• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.353-362
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• 2023

TOC, which can measure more than 90% of organic substances, can be measured quickly and easily,replacing BOD and COD, which were indicators of organic pollutants. According to water quality pollution control standards, when measuring TOC, if the inorganic carbon ratio in the sample is over 50%, the NPOC (Non-Purgeable Organic Carbon) method should be used. If volatile organic compounds (VOCs) are present at a certain concentration, the TC-IC (subtracting inorganic carbon from total carbon) method should be used. To validate the limitations of these analytical conditions, experiments were conducted by varying the ratio of TOC to IC in purified water and measuring the concentration of TOC in test solutions. The results showed no significant difference between the TC-IC method and the NPOC method. When measuring samples with added VOC standard solutions, it was observed that the carbon loss due to purging was not significant when using the NPOC method. Therefore, it is concluded that the choice of analytical method does not lead to significant differences when VOCs are present in the sample. To account for potential variations in results based on water quality pollution control standards and regulations regarding the approval and testing of environmental measurement devices, a comparison of field sample concentration values was made using two widely used types of TOC analyzers in Korea. The results showed variations of 0.02 to 0.83 mg/L between methods depending on the manufacturer, highlighting the need for caution when selecting an instrument.

• The Korean Journal of Physiology
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• v.25 no.2
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• pp.189-200
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• 1991

During the past few years it has been proposed that lithium clearance can be used as a reliable measure for the outflow of tubular fluid from the proximal tubule. This study was aimed to characterize the inflow dependent reabsorption of Na in renal tubule beyond the proximal tubule. For this purpose, lithium clearance was used as a measure for the inflow from the proximal tubule and the changes in reabsorption fraction of Na and water were determined in rabbits. Rabbits were pretreated with hypotonic saline solutions for an hour (50 mM/L NaCl, 20 ml/hr/kg). And then a hypertonic solution of 500 mM/L NaCl (20 ml/kg) was administered intraperitoneally in conjunction with a bolus of LiCl solution (2 mM/kg, i.v.) for conditioning the $C_{Li}$ and urine flow rate. To rule out the effect of $Li^+$ on tubular functions, a bolus of NaCl solution (2 mM/kg, i.v.) was administered. Fifteen, thirty, and sixty minutes after injection of hypertonic saline arterial blood and urine samples were taken. Urinary and plasma concentrations as well as urinary output of $Li^+,\;Na^+\;and\;K^+$ were measured. From these $C_{Li},\;C_{Na}$ and the reabsorption fraction of Na and water $(Fr_{Na}\;&\;FrH_2O)$ were calculated. These results were compared with those from control groups in which the same amount of isotonic saline (145 mM/L NaCl) and of 15% dextran solution were administered in the same way as that in experimental group. Followings are the results obtained. 1) The plasma concentration of $Na^+$ in rabbits injected with hypertonic saline reached the peak value after 15 min and thereafter no significant change was observed. Hematocrit values did not show any change, while urinary excretion of $Na^+$ increased markedly during the first 15 min and decreased thereafter. These results were not affected by an injection of a small amount of LiCl. 2) The clearances of $Li^+,\;Na^+\;and\;K^+$ in rabbits injected with hypertonic saline and LiCl solution decreased. 3) In spite of the variation in $C_{Li},\;Fr_{Na}$ did not show any significant change while $FrH_2O$ increased gradually. 4) $C_{Li}$ decreased also in rabbits received isotonic saline. $Fr_{Na}$ tended to be higher than that in hypertonic saline group, while $FrH_2O\;and\;Fr_{Na}$ did not associated with the decrease in $C_{Li}$. 5) $C_{Li}$ of the rabbits received dextran solution fluctuated persistently and $Fr_{Na}\;and\;FrH_2O$ did not change in along with $C_{Li}$ although $Fr_{Na}$ had a tendency to be higher than that in hypertonic saline group. 6) From the above results it was concluded that: (a) In rabbits with normal body store of $Na^+$, the $Fr_{Na}$ of renal tubule beyond proximal tubule. calculated from $C_{Li}$ as a measure of inflow from proximal tubule is constant in spite of variations in $C_{Li}$. (b) The $FrH_2O$ calculated from $C_{Li}$ is dependent largely upon ADH rather than inflow from proximal tubule. (c) When there is a decrease in plasma $Na^+$ concentration or ineffective body fluid. $Li^+$ reabsorption may occur in the thick segnent of Henle's loop and hence the determination of $Fr_{Na}$ and $FrH_2O$ will not be easy one, but $Fr_{Na}$ is constant under the same experimental conditions.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.51-58
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• 2019

Purpose In in-vitro laboratories of nuclear medicine department, when the reagent lot or reagent lot changes Comparability test or parallel test is performed to determine whether the results between lots are reliable. The most commonly used standard domestic laboratories is to obtain %difference from the difference in results between two lots of reagents, and then many laboratories are set the standard to less than 20% at low concentrations and less than 10% at medium and high concentrations. If the range is deviated from the standard, the test is considered failed and it is repeated until the result falls within the standard range. In this study, several tests are selected that are performed in nuclear medicine in-vitro laboratories to analyze parallel test results and to establish criteria for customized percent difference for each test. Materials and Methods From January to November 2018, the result of parallel test for reagent lot change is analyzed for 7 items including thyroid-stimulating hormone (TSH), free thyroxine (FT4), carcinoembryonic antigen (CEA), CA-125, prostate-specific antigen (PSA), HBs-Ab and Insulin. The RIA-MAT 280 system which adopted the principle of IRMA is used for TSH, FT4, CEA, CA-125 and PSA. TECAN automated dispensing equipment and GAMMA-10 is used to measure insulin test. For the test of HBs-Ab, HAMILTON automated dispensing equipment and Cobra Gamma ray measuring instrument are used. Separate reagent, customized calibrator and quality control materials are used in this experiment. Results 1. TSH [%diffrence Max / Mean / Median] (P-value by t-test > 0.05) C-1(low concentration) [14.8 / 4.4 / 3.7 / 0.0 ] C-2(middle concentration) [10.1 / 4.2 / 3.7 / 0.0] 2. FT4 [%diffrence Max / Mean / Median] (P-value by t-test > 0.05) C-1(low concentration) [10.0 / 4.2 / 3.9 / 0.0] C-2(high concentration) [9.6 / 3.3 / 3.1 / 0.0 ] 3. CA-125 [%diffrence Max / Mean / Median] (P-value by t-test > 0.05) C-1(middle concentration) [9.6 / 4.3 / 4.3 / 0.3] C-2(high concentration) [6.5 / 3.5 / 4.3 / 0.4] 4. CEA [%diffrence Max / Mean / median] (P-value by t-test > 0.05) C-1(low concentration) [9.8 / 4.2 / 3.0 / 0.0] C-2(middle concentration) [8.7 / 3.7 / 2.3 / 0.3] 5. PSA [%diffrence Max / Mean / Median] (P-value by t-test > 0.05) C-1(low concentration) [15.4 / 7.6 / 8.2 / 0.0] C-2(middle concentration) [8.8 / 4.5 / 4.8 / 0.9] 6. HBs-Ab [%diffrence Max / Mean / Median] (P-value by t-test > 0.05) C-1(middle concentration) [9.6 / 3.7 / 2.7 / 0.2] C-2(high concentration) [8.9 / 4.1 / 3.6 / 0.3] 7. Insulin [%diffrence Max / Mean / Median] (P-value by t-test > 0.05) C-1(middle concentration) [8.7 / 3.1 / 2.4 / 0.9] C-2(high concentration) [8.3 / 3.2 / 1.5 / 0.1] In some low concentration measurements, the percent difference is found above 10 to nearly 15 percent in result of target value calculated at a lower concentration. In addition, when the value is measured after Standard level 6, which is the highest value of reagents in the dispensing sequence, the result would have been affected by a hook effect. Overall, there was no significant difference in lot change of quality control material (p-value>0.05). Conclusion Variations between reagent lots are not large in immunoradiometric assays. It is likely that this is due to the selection of items that have relatively high detection rate in the immunoradiometric method and several remeasurements. In most test results, the difference was less than 10 percent, which was within the standard range. TSH control level 1 and PSA control level 1, which have low concentration target value, exceeded 10 percent more than twice, but it did not result in a value that was near 20 percent. As a result, it is required to perform a longer period of observation for more homogenized average results and to obtain laboratory-specific acceptance criteria for each item. Also, it is advised to study observations considering various variables.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.500-509
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• 2014

To prevent freezing of the road by fallen snow, Calcium chloride($CaCl_2$) as a deicer is used to very often and it can be harmful to roadside trees. This study was conducted to investigate the effects of Calcium chloride($CaCl_2$) as a deicer on growth and physiological traits of Acer triflorum according to different concentration of $CaCl_2$. We measured growth, chlorophyll contents, gas exchangement characteristics, chlorophyll fluorescence and mineral nutrition concentration in plant and soil. The experimental group was composed of four treatments including 0mM(control), 9mM(0.5 %), 18mM(1.0 %), 54mM(3.0 %). Before germinating new shoot, the dissolution of $CaCl_2$ was irrigated twice interval of a week. At 30 days after treatment, all treatments decreased total cholorophyll content, photosynthetic rate, transpiration rate, stomatal conductance and photochemical efficiency($F_v/F_m$) with increasing concentration of $CaCl_2$ and especially, they significantly reduced in 3.0 % treatment. In contrast, chlorophyll a/b ratio increased with an increase of $CaCl_2$ concentration and water use efficiency increased in 1.0 % and 3.0 % treatments. At 50 days after treatment, all treatments were decreased in chl a, chl b, total chlorophyll content, carotenoid content, photosynthetic capacity, photochemical efficiency($F_v/F_m$) and quantum yield of photosystem II(${\Phi}_{PSII}$) compared with control and 3.0 % treatments were withered. $Ca^{2+}$ and $Cl^-$ were accumulated in leaves and soil, which inhibited water absorption and electron transport and it caused the reduction of height growth rate more than 50 %. Although there was a little difference according to time and $CaCl_2$ concentration, all treatments decreased in growth rate and physiological activity slowed down. As time passed, these results got worse. Therefore we need to take a measure earlier in order to minimize damage of trees.

• Journal of Veterinary Clinics
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• v.32 no.5
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• pp.426-432
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• 2015

This study compared blood metabolites during peri- and postpartum periods among cows with clinical or subclinical endometritis and cows without endometritis. Blood samples from 207 Holstein dairy cows were collected at 4 weeks prepartum, just after calving, and at 1, 2, 4, and 6 weeks postpartum to measure serum concentrations of calcium, magnesium, non-esterified fatty acids (NEFAs), total cholesterol, albumin, urea nitrogen, ${\beta}$-hydroxybutyrate (BHBA), aspartate aminotransferase (AST), ${\gamma}$-glutamyltransferase, glucose, and phosphorus. Clinical endometritis was diagnosed by the observation of vaginal discharge (> 50% pus) and subclinical endometritis was diagnosed by the evaluation of uterine cytology (> 18% neutrophils) at 4 weeks postpartum. Cows were divided into three groups based on the presence or absence of clinical or subclinical endometritis: the control group (n = 104), the clinical endometritis group (n = 66), and the subclinical endometritis group (n = 37). Calcium and magnesium concentrations were lower in the clinical endometritis group than in the control and subclinical endometritis groups throughout the study period (p < 0.05 to 0.0001), whereas the NEFAs concentration was higher in the clinical endometritis group than in the control group throughout the study period (p < 0.01). The total cholesterol concentration was lower in the clinical endometritis group than in the control and subclinical endometritis groups throughout the pre- and postpartum periods (p < 0.05 to 0.001). The albumin concentration was lower in the clinical endometritis group than in the control and subclinical endometritis groups during the postpartum period (p < 0.05 to 0.001). The urea nitrogen concentration was lower in the clinical endometritis group than in the control and subclinical endometritis groups at 4 and 6 weeks postpartum (p < 0.01). At 1 week postpartum, the BHBA concentration was higher in the clinical endometritis group than in the control group (p < 0.05), whereas the AST concentration was higher in the clinical endometritis and subclinical endometritis groups than in the control group (p < 0.05). In conclusion, lower serum concentrations of calcium, magnesium, total cholesterol, albumin, and urea nitrogen, but higher concentrations of NEFAs, BHBA, and AST during the postpartum period were associated with the incidence of clinical endometritis, indicating the importance of balanced nutrition during the transition period.

• Korean Journal of Medicinal Crop Science
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• v.13 no.1
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• pp.17-20
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• 2005

Natural products has been occasionally used in place of growth regulators to control lateral root formation and growth of soybean sprouts. The study was done to measure the effects of treatment concentration of hard rubber tree (Eucommia ulmoides Oliver) leaf extract on lateral root formation, growth and morphological characters of the sprouts. Seeds of three cultivars, Pungsannamulkong, Sowonkong and Junjery, were imbibed for 5 hours into water, its 5 and 10% solutions immediately before 6 day culture. The cultured sprouts were classified into 4 categories to calculate their composition rates on the base of hypocotyl lengths; >7 cm (A),4 to 7 cm (B),<4 cm (C) and not germinated (D), and their morphological characters, fresh and dry weights were measured. Rate of A was decreased with increased concentrations, while that of C showed reverse result compared to A. Regardless of concentrations, the former rate was less in cv. Junjery than in cv. Pungsannamulkong and Sowonkong than in cv. Junjery although the latter rate was truly opposite to the former one. In 10% treatment concentration, lateral roots were less formed in cv. Junjery although nearly formed in cv. Pungsannamulkong and Sowonkong. In all the 3 cultivars, lateral roots per sprouts were decreased with increased treatment concentration. shorter and thicker sprout was observed in cv. Junjery than in the other cultivars, and in increased concentrations compared to relatively lower ones. Total fresh weight was the greatest in cv. Sowonkong due to mainly increment of its hypocotyl, but was reduced with increased concentration due to mainly decrement of hypocotyl in all the cultivars.

• Korean Parent-Child Health Journal
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• v.3 no.1
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• pp.1-14
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• 2000

The Low Birth Weight infant birth rate in this country is a little more than 15 percent and is being increased. The survival rate of Low Birth Weight infant is over 90 percent and recently the rate runs is getting. However, because of the high risk of Low Birth Weight infant for handicap in growth, a preventive nursing intervention program for Low Birth Weight infant and their mother is considered to be necessary. Touch and massage, thus sensory stimulation has been considered to be important ensuring a normal growth of Low Birth Weight infant During the past decades sensory stimulation program has been used for premature and Low Birth Weight infants. Recently a study on the sensory stimulation for Low Birth Weight infants has bee n done in this country. Mother and infant relationship has a great influence on child's development. Especially, mother and infant interaction during one year after birth plays important role in child's social. affective and cognitive developments. But in the study of Low Birth Weight infants, the mother and infant interaction has been rare yet. However, there was no study effectiveness of the sensory stimulation on mother and infant interaction. In this respect, this study based on the importance of the nursing intervention, is intended to measure the effectiveness of the massage therapy in the aspects of weight, daily feeding amount, cortisolurine stress hormone and mother and infant interactions. This study has been conducted on the nonequivalent control group pretestposttest design in quasi experimental basis and Low Birth Weight infants from NICU of two Medical University Hospitals located in Taegu Metropolitan were selected in experimental group of 21 infants and control group of 20 infants. Data has been collected from May 1, 1999 to September 5, 2000. For the experimental group Field's sensory stimulation(tactile and kinesthetic stimulation) was applied 2 times a day for 10 days(10:00 - 11:00 hours in the morning and 19:00 - 20:00 in the afternoon) by nurse and mother. The electronic indicator scale (Cas Co. Korea) was used to measure infant's body weight. To determine urine cortisol concentration level under stress, rad immuno assay method was used. And to determine mother and infant interactions during feeding, tools developed by Kim Mi-Ye (1999) were used. Collected data were analyzed with SAS program using x-test, t-test, paired t-test and repeated measures ANOVA. Findings were as follows : 1. For the daily mean weight gain, the experimental group showed little higher than the control group, even though, there was no Statistically significant differences between two groups. 2. For the amount of daily mean feeding, the experimental group showed little higher than the control group, while there was no Statistically significant differences between two groups. 3. The level of wine cortisol concentration was increased in both groups, while no Statistical significance was shown between the two groups. 4. Mothers in experimental group were more likely to have higher mean scores in mother and infant interaction during feeding than mothers in the control group. Statistical significance was shown between the two groups(t= 5.78, P=.001). In conclusion, the massage therapy in this study showed with regard to even though through there was no statistically significance in the weight gain and urine stress hormone concentration. there was Statistical significantly higher in the mother and infant interaction during feeding. Based on the result of this study, it is considered that the massage therapy should be applied clinical practice and home to help a developmental growth and interaction of Low Birth Weight infants and mothers during the period of recovery.