• Analytical Science and Technology
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• v.29 no.2
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• pp.57-64
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• 2016

Many phthalic acid esters (PAEs), including DMP, DEP, DBP, BBP, and DEHP, as well as DEHA are widely used as plasticizers in plastics. An analytical method was developed and used to analyze these compounds at 41 industrial facilities. The coefficient of determination (R²) for each constructed curve was higher than 0.98. The method detection limit (MDL) values were 0.4–0.7 μg/L for PAEs and 0.6 μg/L for DEHA. In addition, the recovery rate was shown to be 77.0–92.3%, while the relative standard deviation was shown to be in the range of 5.8-10.5%. DMP (n = 3), DEP (n = 2), DBP (n = 2), BBP (n = 2), and DEHA (n = 3) were detected in the range of 2.2-11.1% in the influent. DEHP was a predominant compound and was detected at > MDL in both the influent (n = 16, 35.6%) and the effluent (n = 4, 10.0%) at a high removal efficiency (92–100%). The highest levels of residue in industrial wastewater influent were 137.4 μg/L of DEHP at plastic products manufacturing facility, 12.5 μg/L of DEHA at a chemical manufacturing facility, and 14.0 μg/L of DEP at an electronics facility. The highest concentration of effluent was 12.5 μg/L of DEHP at a chemical manufacturing facility, which indicated that the effluent was below the allowable concentration (800 μg/L). Therefore, the levels of PAEs and DEHA that are discharged into nearby streams could not influence the health of the ecosystem.

• Analytical Science and Technology
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• v.23 no.1
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• pp.1-14
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• 2010

It is of importance that all countries in worldwide, including EU and China, have adopted the Restrictions on the use of certain Hazardous Substances (RoHS) for all electronics. IEC62321 document, which was published by the International Electronics Committee (IEC) can have conflicts with the standards in the market. On the contrary Publicly Accessible Specification (PAS) for sampling published by IEC TC111 can be adopted for complementary application. In this work, we tried to find a route to disassemble and disjoint cellular phone sample, based on PAS and compare the screening methods available in the market. For this work, the cellular phone produced in 2001, before the regulation was born, was chosen for better detection. Although X-ray Fluorescence (XRF) showed excellent performance for screening, fast and easy handling, it can give information on the surface, not the bulk, and have some limitations due to significant matrix interference and lack of variety of standards for quantification. It means that screening with XRF sometimes requires supplementary tool. There are several techniques available in the market of analytical instruments. Laser ablation (LA) ICP-MS, energy dispersive (ED) XRF and scanning electron microscope (SEM)-energy dispersive X-ray (EDX) were demonstrated for screening a cellular phone. For quantitative determination, graphite furnace atomic absorption spectrometry (GF-AAS) was employed. Experimental results for Pb in a battery showed large difference in analytical results in between XRF and GF-AAS, i.e., 0.92% and 5.67%, respectively. In addition, the standard deviation of XRF was extremely large in the range of 23-168%, compared with that in the range of 1.9-92.3% for LA-ICP-MS. In conclusion, GF-AAS was required for quantitative analysis although EDX was used for screening. In this work, it was proved that LA-ICP-MS can be used as a screening method for fast analysis to determine hazardous elements in electrical products.

• Journal of Yeungnam Medical Science
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• v.10 no.1
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• pp.190-196
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• 1993

The prognosis of chronic hepatitis C is very variable. In some, the disease is progressive and cirrhosis can develop from chronic hepatitis C. Hepatitis C virus(HCV) may act as a trigger towards hepatocellular carcinoma in patients with cirrhosis. Interferon has been used for the treatment of chronic hepatitis C in abroad, 16 patients with chronic C liver disease were treated with ${\alpha}$-interferon (alfa-2b; "Intron A" Schering Corp. Kenilworth. NJ). All patients were given ${\alpha}$-interferon in subcutaneous doses of 3 million units three times weekly for 1 to 9 months. During therapy, CBC and ALT levels were checked weakly to monthly. After therapy, patients were followed for 1 to 8 months. Among 16 patients treated with ${\alpha}$-interferon, progressive decrease of ALT levels was observed in 14(87.5%). In 11 patients(68.8%), ALT levels fell into the normal range during therapy, and in 9 of 11, within one month after therapy, 6 months after the completion of therapy in 4 of 9 patients(44.4%) whose ALT levels were in the normal range, ${\alpha}$-interferon seems to have effect in controlling disease activity in patients with chronic hepatitis C. But the changes in the usage of ${\alpha}$-interferon, dose and duration, long term follow up and more convenient and simple tests for HCV detection are recommended for the better effect and the exact evaluation on the effect of ${\alpha}$-interferon therapy in patients with chronic hepatitis C.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.502-508
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• 2009

Background: Rib fractures are the most common injuries that are caused by blunt chest trauma. However, fractures of the costal cartilage generally go unnoticed on chest X-rays unless they involve a calcified cartilage. For this reason, the sensitivity of conventional radiography for detecting rib fractures is low, and especially those involving the cartilaginous part of the rib. Thus, we have evaluated the usefulness of ultrasonography for detecting fractures of the costal cartilage that were overlooked on the conventional radiographs of patients who suffered minor blunt chest traumas. Material and Method: A total of 45 patients who suffered minor blunt chest trauma and who had no evidence of rib fractures or other major fractures on conventional radiographs were admitted for ultrasonography between April 2008 and March 2009. There were 24 women and 21 men, and the mean age of the patients was 50.4$\pm$15.91 years (range: 17$\sim$76 years). They were examined for the detection of fractures of the costal cartilage by performing ultrasonography with a 7.5-MHz linear transducer. Result: A total of 30 patients (67%) had fractures of the costal cartilage, whereas 15 patients (33%) had no evidence of chondral rib fractures. The mean number of fracture sites of the fractured costal cartilage was 1.6$\pm$0.81 (range: 1$\sim$4 sites) in 30 patients. Periosteal hematoma was the most common finding associated with fractures of the costal cartilage (n=7, 17%), followed by sternum fracture (n=5, 12%). However, periosteal hematoma was noticed in 1 patient (2%) who was without fracture of the costal cartilage, and sternum fracture was noticed in 1 patient (2%) who was without fractures of the costal cartilage. Conclusion: The results of this study suggest that ultrasonography may be a useful imaging modality for detecting fractures of the costal cartilage that are overlooked on the conventional radiographs of patients who suffer minor blunt chest trauma.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.955-961
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• 2014

This study was carried out to investigate the amounts of vitamin C in 22 sweet potato cultivars cultivated in Korea as well as evaluate the effects of cooking methods on vitamin C contents. Methods for determining vitamin C was validated by determining linearity, specificity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy using HPLC. Results showed high linearity in the calibration curve with a coefficient of correlation ($R^2$) of 0.9999. The LOD and LOQ values for ascorbic acid (AA) were 0.03 and $0.10{\mu}g/mL$, respectively. The relative standard deviations (RSDs) for intra- and inter-day precision of AA were less than 5%. The recovery rates of AA and dehydroascorbic acid (DHA) were in the range from 98.21~98.64 and 98.28~100.68%, respectively. Depending on cultivar, contents of AA, DHA, and total ascorbic acid (TA) in sweet potatoes varied in the range from 37.76 (Sinyulmi)~89.25 (Juhwangmin), 23.37 (Sinjami)~63.94 (Sinyulmi), and 68.52 (Sinjami)~115.95 (Juhwangmin) mg/100 g, respectively, and their average levels were $56.98{\pm}12.53$, $36.46{\pm}9.03$, and $93.44{\pm}12.00mg/100g$, respectively. The average TA levels were also dependent on flesh color, whish was significantly higher in general sweet potato and orange sweet potato than in purple sweet potato. Steaming, baking, and frying processes significantly reduced AA (10.61~58.41%), DHA (2.57~52.81%), and TA (14.54~49.92%) contents in sweet potatoes. The highest reduction of AA, DHA, and TA contents was observed after baking, followed by steaming and frying. We expect that the basic information provided by this study will be useful to plant breeders and food scientists.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.1
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• pp.35-45
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• 2018

Image data collected by an airborne hyperspectral camera system have a great usability in coastal line mapping, detection of facilities composed of specific materials, detailed land use analysis, change monitoring and so forh in a complex coastal area because the system provides almost complete spectral and spatial information for each image pixel of tens to hundreds of spectral bands. A few approaches after classifying by a few approaches based on SAM(Spectral Angle Mapper) supervised classification were applied for extracting optimal land cover information from hyperspectral images acquired by CASI-1500 airborne hyperspectral camera on the object of a coastal area which includes both land and sea water areas. We applied three different approaches, that is to say firstly the classification approach of combined land and sea areas, secondly the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas, and thirdly the land area-only classification approach using atmospheric correction images and compared classification results and accuracies. Land cover classification was conducted respectively by selecting not only four band images with the same wavelength range as IKONOS, QuickBird, KOMPSAT and GeoEye satelllite images but also eight band images with the same wavelength range as WorldView-2 from 48 band hyperspectral images and then compared with the classification result conducted with all of 48 band images. As a result, the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas is more effective than classification approach of combined land and sea areas. It is showed the bigger the number of bands, the higher accuracy and reliability in the reclassification approach referred above. The results of higher spectral resolution showed asphalt or concrete roads was able to be classified more accurately.

• Clinical and Experimental Pediatrics
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• v.50 no.8
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• pp.774-780
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• 2007

Purpose : The anthracyclines (AC) are widely used chemotherapeutic agents for pediatric cancers. However, the therapeutic use of these agents is limited by their cardiotoxicity. The aim of the present study was to investigate the usefulness of plasma B-type natriuretic peptide (BNP) levels as a marker for AC-induced cardiotoxicity compared to echocardiography in Korean children with cancer. Methods : Fifty-five pediatric cancer patients who had received chemotherapy including AC were enrolled. The cumulative AC doses, clinical symptoms, and two echocardiography parameters, left ventricular fractional shortening (LVFS) and left ventricular ejection fraction (LVEF), were studied and compared with plasma BNP levels. Results : In 55 patients, plasma BNP levels were measured 115 times and echocardiographies were performed 64 times. The median cumulative dose of AC was $325mg/m^2$ (range 120-600; mean 345) and the median plasma BNP level was 10 pg/mL (range 5-950; mean 31). The cumulative AC doses correlated significantly with the plasma BNP levels (P=0.002). The plasma BNP levels correlated significantly with LVFS (P=0.018) and LVEF (P=0.025). Dilated cardiomyopathies were identified in three patients. LVFS and LVEF decreased and plasma BNP levels increased in a patient with acute dilated cardiomyopathy and in that with symptomatic chronic dilated cardiomyopathy. However, LVFS, LVEF and plasma BNP levels were normal in a patient with asymptomatic chronic dilated cardiomyopathy. Conclusion : The results of this study demonstrated that plasma BNP levels could be used as a marker for AC-induced cardiotoxicity; they showed good correlation with echocardiography findings in pediatric cancer patients. Plasma BNP levels may be used for the detection and management of AC-induced cardiotoxicity in Korean children with cancer.

• Journal of Food Hygiene and Safety
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• v.19 no.1
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• pp.12-18
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• 2004

Ofloxacin, norfloxacin, ciprofloxacin, and enrofloxacin in chicken muscle were seperated by liquid extraction and determined with high performance liquid chromatography (HPLC) with fluorescence detector. Analysis was carried out using following conditions; Cl8 column (250${\times}$4.6 mm i.d. 5 ${\mu}{\textrm}{m}$ particle size), mobile phase composed of D.W. (containing 0.4% triethylamine and phospholic acid): methanol : acetonitrile (800:100:100, v/v/v), isocratic pump at a flow rate of 1.0 $m\ell$/min and 50 ${mu}ell$ of injection volume, fluorescence detector with EX278 nm/EM.456 nm. The calibration curves of four fluoroquinolones showed linearity (${\gamma}$$^2$$\geq$0.999) at concenration range of 0.025-0.6 $\mu\textrm{g}$/ml. The recoveries in fortified chicken muscle represented more than 80% with low coefficient of variation (〈10%) for concentration range of four fluoroquinolones. The detection limits for ofloxacin, norfloxacin, ciprofloxacin, and enrofloxacin were 23.5, 3.4, 3.0 and 2.5 ng/g in chicken muscle, respectively. We also monitored fluoroquinolones residue in muscle of chickens (broiler 1:227, Korean native chicken 219, laying chicken 77) using EEC-4-plate screening and HPLC conformation methods. Ten(broiler 5, Korean native chicken 5) out of the fifteen samples which were positively detected by EEC-plate screening method from 1,523 chicken meat were confirmed with ciprofloxacin and enrofloxacin by HPLC. The ranges of residual concentration were 0-0.12 ppm for ciprofloxacin and 0.01-6.79 ppm for enrofloxacin. In conclusion, our method could be applied effectively to determine four fluoroquinolones residues in chicken meat, and further survey for fluoroquinolones residue in chicken meat are needed for more effective control of fluoroquinolones used in livestock.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.327-333
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• 2014

A method for analysis of five artificial sweetners (sodium saccharin, aspartame, acesulfame-K, sucralose, cyclamate) in beverage samples was developed using high-performance liquid chromatography/triple quadrupole mass spectrometry (HPLC/MS/MS). The method uses a single-step dilution for sample preperation. Seperation was achieved on a $C_{18}$ column ($2.1{\times}150mm$, $3.5{\mu}m$) with A- 2% methanol (1 mM ammonium acetate), B-95% methanol (1 mM ammonium acetate) as mobile phase with gradient mode. The quantitation of target compounds was performed by external calibration in selected reaction monitorning (SRM) mode. The coefficient of determination of calibration curve for sodium saccharin, aspartame, acesulfame-K, sucralose and cyclamate were 0.9957, 0.9991, 0.9943, 0.9982 and 0.9948, respectively. The limits of detection (LODs) and limits of quantitation (LOQs) were in the range of 0.001~0.022 mg/L and 0.004~0.073 mg/L, repectively. Recoveries for beverage samples were in the range of 92.76~113.50% with RSD < 10.91%. The method has applied to the determination of the five sweetners in 102 beverage samples. Three artificial sweetners-aspartame, acesulfame-K, sucralose were detected from 42 samples. Sodium saccharin and cyclamate were not detected in all samples.

• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.29-39
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• 1999

An earlier study of the effect of rain found that the capacity of freeway systems was reduced, but did not address the effects of rain on the nature of traffic flows. Indeed, the substantial variation due to the intensity of adverse weather conditions is entirely rational so that its effects must be considered in freeway facility design. However, all of the data in Highway Capacity Manual(HCM) have come from ideal conditions. The primary objective of this study is to investigate the effect of rain on urban freeway traffic flows in Seoul. To do so, the relations between three key traffic variables(flow rates, speed, occupancy), their threshold values between congested and uncontested traffic flow regimes, and speed distribution were investigated. The traffic data from Olympic Expressway in Seoul were obtained from Imagine Detection System (Autoscope) with 30 seconds and 1 minute time periods. The slope of the regression line relating flow to occupancy in the uncongested regime decreases when it is raining. In essence, this result indicates that the average service flow rate (it may be interpreted as a capacity of freeway) is reduced as weather conditions deteriorate. The reduction is in the range between 10 and 20%, which agrees with the range proposed by 1994 US HCM. It is noteworthy that the service flow rates of inner lanes are relatively higher than those of other lanes. The average speed is also reduced in rainy day, but the flow-speed relationship and the threshold values of speed and occupancy (these are called critical speed and critical occupancy) are not very sensitive to the weather conditions.