• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.208-222
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• 2000

This study was conducted to supplement limit of previous study, The objectives of this study were to select optimal conditions of high performance liquid chromatography(HPLC) operation for detecting urinary 2-thiothiazolicline-4-carboxylic acid(TTCA) and thiocarbamide simultaneously, and to evaluate recovery rates for various liquid-liquid extration method of these metabolites, The results are as follows : 1. The urinary TTCA and thiocarbamide were separate sharply when flow rate is $0.7m{\ell}/min$, using a series $C_8$ and $C_{18}$ column, 50 mM $KH_2PO_4$ : acetonitrile (93.5 : 6.5) and pH 3.5 as a mobile phase. The retention time was TTCA, $12.07{\pm}0.11$(mean${\pm}$SD, n=06), thiocarbamide, $7.85{\pm}0.01$ (mean${\pm}$SD, n=6), respectively. The calibration curve for TTCA and thiocarbamide was linear within the range 0.05 to $30{\mu}g/m{\ell}$. 2. By the liquid-liquid extration, butanol extration with $(NH_4)_2$ as a salting-out reagent was used as a simultaneous extration method for these metabolites in acid state, and recovery rates of this method are urinary TTCA, $49.6{\pm}17.7$ (mean${\pm}$SD, n=16), thiocarbamide, $43,9{\pm}5.50$ (mean${\pm}$SD, n=16), respectively 3. The precision(pooled coefficients of variation for 4 concentration) of the urinary thiocarbamide analysis was 0.03754 by butanol liquid-liquid extraction with $(NH_4)_2$ as a salting-out reagent, and TTCA was 0.04082 by ethyl acetate liquid-liquid extration with $(NH_4)_2$ as a salting out reagent The above results show that the butanol liquid-liquid extraction with $(NH_4)_2$ as a salting-out reagent in acid state, and using a series $C_8$ and $C_{18}$ column, 50 mM $KH_2PO_4$ : acetonitrile (93.5 : 6.5) and pH 3.5 as a mobile phase are suitable for the analysis of urinary TTCA and thiocarbamide simultaneously. The detection limit of TTCA and thiocarbamide was about $0.17{\mu}g/m{\ell}$, $0.07{\mu}g/m{\ell}$.

• Korean Journal of Veterinary Research
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• v.51 no.4
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• pp.253-257
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• 2011

Amikacin is a semisynthetic derivative of kanamycin and primarily active against aerobic Gram-negative-pathogens with limited activity against Gram-positive bacteria. Meager study was reported on pharmacokinetic data on multi-days administration of amikacin. Hence, pharmacokinetics study was done in five clinically healthy goats (n = 5), after intravenous bolus injection of amikacin sulfate at the dose rate of 10 mg/kg body weight daily for three consecutive days. The amikacin concentrations in plasma and pharmacokinetics-parameters were analyzed by using microbiological assay technique and noncompartmental open-model, respectively. The mean peak plasma concentrations (Mean ${\pm}$ SD) of amikacin at time zero ($Cp^{0}$) was $114.19{\pm}20.78$ and $128.67{\pm}14.37{\mu}g/mL$, on day 1st and 3rd, respectively. The mean elimination half-life ($t_{1/2}ke$) was $1.00{\pm}0.28h$ on day 1st and $1.22{\pm}0.29h$ on day 3rd. Mean of area under concentration-time curve ($AUC_{0{\rightarrow}{\infty}}$) was $158.26{\pm}60.10$ and $159.70{\pm}22.74{\mu}g.h/mL$, on day 1st and 3rd respectively. The total body clearance ($Cl_{B}$) and volume of distribution at steady state (Vdss) on day 1st and 3rd were $Cl_{B}=0.07{\pm}0.02$ and $0.06{\pm}0.01L/h.kg$ and $Vdss=0.10{\pm}0.03$ and $0.11{\pm}0.05L/kg$, respectively. No-significant difference was noted in both drug-plasma concentration and pharmacokinetics-parameters, respectively. Amikacin concentration in plasma was found higher up-to 4 h and 6 h onward on down-ward trends favour to reduce toxicity. Which also support the pharmacokinetic-pharmacodynamic way of dosing of aminoglycosides and hence, amikacin may be administered 10 mg/kg intravenously daily to treat principally Gram-negative pathogens and limitedly Gram-positive-pathogens.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.817-830
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• 2023

This study investigates the age of the surficial rocks in the Arunta region using Uranium-Lead (U-Pb) geochronological dating. Rock samples were collected at four locations, Cattle-Water Pass (CP 1610), Gough Dam (GD 1622 and GD 1610), and London-Eye (LE 1601), within the Strangways Metamorphic Complex and crushed by selFragging. Subsequently, the zircon grains were imaged using Cathodoluminescence (CL) analysis and the U-Pb (uranium and lead) isotope ratios and the chrono-stratigraphy were measured. The imaged zircon revealed an anomalous heterogeneous crystal structure. Ellipses of the samples at locations GD1601, CP1610, and GD1622 fall below the intercept indicating the ages produced discordant patterns, whereas LE1601 intersects the Concordia curve at two points, implying the occurrence of an event of significant impact. For the rock sample at CP1610, the estimated mean age is 1742.2 ± 9.2 Ma with mean squared weighted deviation (MSWD) = 0.49 and probability of equivalence of 0.90; 1748 ± 15 Ma - MSWD = 1.02 and probability of equivalence of 0.40 for GD1622; and 1784.4 ± 9.1 Ma with MSWD of 1.09 and probability of equivalence of 0.37 for LE1601. But for samples at GD1601, two different age groups with different means occurred: 1) below the global mean (1792.2 ± 32 Ma) estimated at 1738.2 ± 14 Ma with MSWD of 0.109 and probability of equivalence of 0.95 and 2) above it with mean of 1838.22 ± 14 Ma, MSWD of 1.6 and probability of equivalence of 0.95. Analysis of the zircon grains has shown a discrepancy in the age range between 1700 Ma and 1800 Ma compared to the ASO dated to have occurred between 440 and 300 Ma. Moreover, apparent similarity in age of the core and rim means that the mineral crystallized relatively quickly without significant interruptions and effect on the isotopic system. This may have constraint the timing and extent of geological events that might have affected the mineral, such as metamorphism or hydrothermal alteration.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1841-1849
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• 2021

Objective: To prospectively investigate the feasibility of shear wave elastography (SWE) as a new quantitative and objective method for evaluating the stiffness of the gastrocnemius medialis (GM) muscle during passive stretching in patients with Parkinson's disease (PD). Materials and Methods: SWE of the GM muscle was performed in 28 patients with PD [13 female and 15 male; mean age ± standard deviation (SD): 63.0 ± 8.5 years] and 12 healthy controls (5 female and 7 male; mean age ± SD: 59.3 ± 6.4 years) during passive ankle rotation. A Young's modulus-ankle angle curve was constructed. The GM slack angle and baseline Young's modulus (E₀) were compared between the markedly symptomatic and mildly symptomatic sides of patients with PD, and healthy controls. Additionally, the correlation between the GM slack angle and the severity of rigidity, and the observer reproducibility of SWE in determining the GM slack angle were evaluated. Results: The GM slack angle was smaller on both the markedly and mildly symptomatic sides in patients with PD than in healthy controls (mean ± SD of -29.13° ± 3.79° and -25.65° ± 3.39°, respectively, vs. -21.22° ± 3.52°; p < 0.001 and p = 0.006, respectively). Additionally, in patients with PD, the GM slack angle on the markedly symptomatic side was smaller than that on the mildly symptomatic side (p = 0.003). The E0 value was lower on both the markedly and mildly symptomatic sides in patients with PD than in healthy controls (mean ± SD of 10.11 ± 2.85 kPa and 10.08 ± 1.88 kPa, respectively, vs. 12.23 ± 1.02 kPa; p = 0.012 and p < 0.001, respectively). However, no significant difference was found between the markedly and mildly symptomatic sides in patients with PD (p = 0.634). A negative linear relationship was observed between the GM slack angle and lower limb rigidity score on the markedly symptomatic side in patients with PD (r = -0.719; p < 0.001). The intraclass correlation coefficients for observer reproducibility of SWE ranged from 0.880 to 0.951. Conclusion: The slack angle determined by SWE may be a useful quantitative and reproducible method for evaluating muscle stiffness in patients with PD.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.87-94
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• 2011

Flavonoid contents of common buckwheat (cv. Kitawase) and tartary buckwheat (cv. Hokkai T 8, Hokkai T 9 and Hokkai T 10) were determined by high-performance liquid chromatography (HPLC). Moreover, they were measured at different plant developments such as 10, 18, 20, 22 and 30 days after sowing (DAS) and with plant parts including leaf, stem and flower harvested at 30 DAS. Total flavonoids including chlorogenic acid, four kinds of C-glycosylflavones (orientin, isoorientin, vitexin, isovitexin) and rutin of tartary buckwheats (range of 44.2-54.7, mean 44.2) were found 35% higher than those of common buckwheat (28.9 mg/g dry wt.). Among them, rutin was measured above 80% of total flavonoid contents. The other flavonoids (chlorogenic acid and four kinds of C-glycosylflavones) presented the highest level at 10 DAS and decreased according to plant developments. On the other hand, rutin content of Kitawase presented the highest level (33.6 mg/g dry wt.) at 22 DAS and decreased up to 30 DAS. Rutin content in tartary buckwheat temporarily decreased from 10 to 18 DAS and then reversely increased up to 30 DAS presented the highest level as 'U' curve. In Hokkai T 10, rutin content was found the highest level (53.8 mg/g dry wt.) at 30 DAS. In different plant parts harvested at 30 DAS, rutin content of leaf (range of 42.8-68.0, mean 57.0) was 5.3-fold higher than that of stem (range of 8.0-15.9, 10.8 mg/g dry wt.), regardless of cultivar. Significantly, rutin content (78.7) in the flower of Kitawase was 1.8 times higher than in the leaf and 9.8 times in the stem. Especially, chlorogenic acid content (14.6 mg/g dry wt.) in the flower of Kitawase was 63-fold higher than in the leaf, and 20-fold in the stem.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.11 s.353
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• pp.95-117
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• 2006

In this paper, we describe the optimization of the link-level performance and the complexity of floating-point and fixed-point methods in IEEE 802.16e OFDMA/TDD mobile modem. In floating-point design, we propose the channel estimation methods for downlink traffic channel and select the optimized method using computer simulation. So we also propose efficent algorithms for time and frequency synchronization, Digital Front End and CINR estimation scheme to optimize the system performance. Furthermore, we describe fixed-point method of uplink traffic and control channels. The superiority of the proposed algorithm is validated using the performances of Detection, False Alarm, Missing Probability and Mean Acquisition Time, PER Curve, etc. For fixed-point design, we propose an efficient methodology for optimized fixed-point design from floating-point At last, we design fixed-point of traffic channel, time and frequency synchronization, DFE block in uplink and downlink. The tradeoff between performance and complexity are optimized through computer simulations.

• Journal of Korean Society for Quality Management
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• v.11 no.1
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• pp.10-17
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• 1983

This paper studies item-life test plans with the specified item mean life $T_1$ (MTBF) - Producer's risk ${\alpha}$ and item mean life $T_2$ (MTBF, $T_2$ < $T_1$) - Consumer's risk ${\beta}$ when the probability of item survival follows the Weibull distribution (known shape parameter) as a expansion of [1]. And Operating Characteristic Curves and Average Life-testing Times of item-life test plans are computed for this paper and [1]. Cost analysis procedures are same as [1]. These results are computed by using computer program written in Level II Basic for Apple II Plus Micro-computer. Both this paper and [6] reduce the life-testing time for Weibull distribution in comparision with Exponential distribution, but results of [6] were computed for different criterions from this paper.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.3
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• pp.234-243
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• 2000

This paper is to study population ecological characteristics, including growth parameters, survival rate, instantaneous coefficients of natural and fishing mortalities, and age at first capture of the soft-shelled clam, Mya japonioa in the intertidal zone of South Sea in Korea. For describing growth of the clam a von Bertalanffy growth model was adopted, The von Bertalanffy growth curve had an additive error structure and the growth parameters estimated from a non-linear regression were SH/sub ∞/=79.83mm, K=0.26, and t/sub 0/= -0.01. Survival rate (S) of the soft-shelled clam was 0.26 (SD=0.02). The instantaneous coefficients of natural mortality (M) was estimated to be 0.78/year and fishing mortality (F) 0.57/year for the soft-shelled clam. The age at first capture (t/sub c/) was estimated as 2.69 year. The mean densities of the soft-shelled clam by bottom type were 3.40 inds./m²(SE=0.18) in the sand, 63.4 inds./m²(SE= 0.53) in the muddy sand, and 0 inds./m2 (SE=0) in the gravelly sand. The mean densities of the soft-shelled clam by 3 different areas were 4.88 inds./m²(SE=0.09), 2.61 inds./m²(SE=0.13), 7.20 inds./m²(SE=0.18), respectively and the biomass of the clam were estimated as 131mt, 121mt, 665mt, respectively. An yield-per-recruit analysis showed that the current yield-per-recruit of about 8.30g with F=0.57/year and the age at first capture (t/sub c/) 2.69 year, was lower than the maximum possible yield-per-recruit of 9.60g. Fixing to at the current level and increased fishing intensity (F) could produce an increase in the predicted yield-per-recruit from 8.30g to about 9.40. However, estimated yield-per-recruit increased to 1.30g by decreasing to from the current age (2.69 year) to age two with F fixed at the current level. Yield-per-recruit was estimated under harvest strategies based on F/sub max/ and F/sub 0.1/.

• Journal of fish pathology
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• v.6 no.2
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• pp.123-131
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• 1993

The cultured flounder(Paralichthys olivaceus) was injected with Staphylococcus epidermidis, various hematological and blood chemical changes were monitored over 96 hours. Red blood cell count, hemoglobin hematocrit. mean corpuscular hemoglobin concentration and mean corpuscular hemoglobin were significantly depressed after 24 to 48hours. Total protein, albumin, globulin and total cholestrol were significantly increased by the 24 or 48 hours, Glucose, bilirubin and transaminase were significantly depressed by 24 to 48hours. Erythrocytes were gotten shorter with round-shaped after 48hours inoculated with S. cpidermidis. Hemolytic erythrocytes and neutrophils were showed after 72hours inoculated with S. epidermidis. Price-Jones curve was transformed for left shift after 48hours inoculated with S. epidermidis, therfore staphylococcia appeared hemolytic anemia in the artificially infection.

• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.51-53
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• 2003

This study was conducted to compare the bioavailability of a generic product of Sinil Atenolol Tablets (Sinil Pharmaceutical Co., Ltd., Korea) with the innovator product, $Tenormin^{\circledR}$ Tablets in 20 healthy Korean volunteers. The volunteers received a single 50 mg dose of each atenolol formulation according to a randomized, two-way crossover design. Plasma samples were obtained over a 24-hour interval, and atenolol concentrations were determined by HPLC with a fluorescence detector. From the plasma atenolol concentration vs time curves, the following parameters were compared: area under the plasma concentration-time curve (AUC), peak plasma concentration $(C_{max})$, time to reach peak plasma concentration $(T_{max})$, and terminal first order elimination half-life $(t_{1/2})$. No statistically significant difference was obtained between the $T_{max}$ values, and the logarithmic transformed AUC and $C_{max}$ values of the two products. The 90% confidence for the ratio of the logarithmically transformed AUC and $C_{max}$ values of Sinil Atenolol Tablets over those of $Tenormin^{\circledR}$ Tablets were calculated to be between 0.99 and 1.07, and 1.04 and 1.16, respectively; both were within the bioequivalence limit of 0.80-1.25. The mean of $T_{max}$ in $Tenormin^{\circledR}$ Tablet group was 3.68 hour, and that in Sinil Atenolol Tablet group was 3.65 hour. The values of $t_{1/2}$ between the two products were found comparable, and the mean $t_{1/2}$ values of $Tenormin^{\circledR}$ Tablets and Sinil Atenolol Tablets were 5.9 and 6.0 hour, respectively. Based on these results, it was concluded that Sinil Atenolol Tablets were comparable to $Tenormin^{\circledR}$ Tablets in both the rate and extent of absorption, indicating that Sinil Atenolol Tablets were bioequivalent to the reference product, $Tenormin^{\circledR}$ Tablets