• Journal of the Korean Vacuum Society
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• v.12 no.S1
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• pp.21-27
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• 2003

Micro-arc discharge oxidation (MDO) is a cost-effective plasma electrolytic process which can be used to improve the wear and corrosion resistance of Al-alloy parts by forming a alumina coating on the component surface. However, the MDO coated Al-alloy components often exhibit relatively high friction coefficients and low wear resistance fitted with many counterface materials, additionally, the pitting corrosion for the MDO coated AI-alloy components, especially for a thinner alumina coating, often occurs in atmosphere circumstance due to the porous alumina coats. Therefore, a duplex treatment, combining a MDO coated ahumina thin layer with a TiN coating, prepared by magnetron sputtering (MS), has been investigated. The Vicker's microhardness, pin-on-disc, electrochemical measurement, salt spray, XRD and SEM tests were used to characterize and analyze the treated samples. The work demonstrates that the MDO/MS coated samples have a combination of a very low friction coefficient and good wear resistance as well as corrosion since the micro-holes on alumina coating are partly or fully covered by TiN material.

• Journal of Acupuncture Research
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• v.28 no.6
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• pp.69-83
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• 2011

Objectives : This study aimed to evaluate the effects of Malvae Semen herbal-acupuncture (MS-HA) at$KI_{10}$($Eumgok$) on nephritis induced by lipopolysaccharide (LPS) in rat. Methods : Rats with nephritis induced by LPS, were treated with Malvae Semen herbal-acupuncture(MS-HA) injection at $KI_{10}$. Two control groups, N.P group and Saline group, were treated with 26 gauge needle at $KI_{10}$, 3 times a week. In Saline group, normal saline was injected at $KI_{10}$. To evaluate the effects of Malvae Semen Herbal-acupuncture at $KI_{10}$ on nephritis in rats, WBC, Neutrophils in blood, BUN, Creatinine, TNF-a, CINC-1 in serum, urinal volume, creatinine, total protein in urine and renal TNF-a, renal tissue were analyzed. Results : MS-HA at $KI_{10}$ significantly reduced WBC and neutrophil in blood, TNF-${\alpha}$ in serum of LPS-stimulated rats. MS-HA at $KI_{10}$ significantly reduced total protein level in urine. MS-HA at $KI_{10}$ reduced accumulation of neutrophil in renal tissue of LPS-stimulated rats. Conclusions : Taken together, MS-HA at $KI_{10}$ has a therapeutic effect on nephritis in LPS-stimulated rat. Therefore, it is suggested that MS-HA at $KI_{10}$ may be an useful therapeutics for nephritis in clinical field.

• Analytical Science and Technology
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• v.26 no.1
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• pp.80-85
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• 2013

The sixty nine accident preparedness substances (APS) having high probability of chemical accident are controlled under the Toxic Chemicals Control Act (TCCA). Around the world, there has been a growing interest in the analysis of chemical warfare agent (CWAs). When a chemical accident occurs, it is generally required to detect and identify APS. However, the quantitative analytical data remain limited in Korea. In this study, an analytical method using GC/MS for volatile organic chemicals was established and a quantitative analysis method was studied. The calibration curve for 25 chemicals were obtained and 21 chemicals showed higher coefficient of determination ($r^2$ >0.998).

• BMB Reports
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• v.42 no.8
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• pp.529-534
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• 2009

Marbling score (MS) is the major trait that affects carcass quality in beef cattle. In this study, we investigated the association between genetic polymorphisms of the adipose differentiation-related protein gene (ADFP) and carcass traits in Korean cattle (also known as Hanwoo). Using direct DNA sequencing in 24 unrelated Korean cattle, 25 novel polymorphisms were identified within all exons and their flanking regions of ADFP, including the promoter region (1.5 kb). Among them, 21 polymorphic sites were selected for genotyping in the beef cattle (n = 425). Statistical analyses revealed that one promoter polymorphism (c.-56-18A > G) was associated with MS (P = 0.009). The 'A' allele of c.-56-18A > G exerted a lowering effect on MS, e.g., the lowest MS was found in 'A/A' (MS = 2.09 ${\pm}$ 1.23), intermediate in 'A/G' (MS = 2.11 ${\pm}$ 1.31), and the highest in 'G/G' (MS = 2.47 ${\pm}$ 1.47). Our findings suggest that these polymorphisms in ADFP might be important genetic factors involved in carcass quality in beef cattle.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.2002-2010
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• 2009

The degradation behavior of berberine is examined using GC-MS to select the fingerprint products that can be used to identify berberine dye in badly faded archaeological textiles. A total of $100^{\circ}C$ thermal and $H_2O_2/UV/O_2$ degradation systems were used to degrade berberine chloride 0.1% solution up to 408 hours. The samples were analyzed using the GC-MS. Dihydroberberine, 2-pteridinamine, 6,7-dimethyl-N-[(trimethylsilyl) oxy]-, and 8-methoxy-11-[3-methylbutyl]-11H-indolo[3,2-c]-quinoline, 5-oxide were detected as the major products of thermal degradation and identified as the fingerprint products for berberine dye at the early stage of degradation. Isobenzofuran-1,3-dione,4,5-dimethoxy-, 9H-fluorene,3,6-bis(2-hydroxyethyl)-,1,3-dioxolo[4,5-g]isoquinolin-5(6H)-one,7,8-dihydro-, and 3-tert-butyl-4-hydroxyanisole were detected as the major products generated by the $H_2O_2/UV/O_2$ degradation and identified as the fingerprint products for berberine dye under severe degradation conditions.

• The Journal of Internal Korean Medicine
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• v.33 no.3
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• pp.243-256
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• 2012

Objectives : This clinical study was done to examine metabolic syndrome (MS) and plasma homocysteine (HCY) level in patients with silent lacunar infarction (SLI) and in normal controls. Methods : A total of 154 patients, who were over 20 years of age and visited the stroke prevention check-up center of a university hospital from December 2006 to December 2010, were examined by brain CT or brain MRI, and classified into two groups. We compared the components of MS and HCY levels between patients with SLI (n=74) and normal controls (n=80). Modified ATP III definition was used for diagnosis of MS while Korean standard for waist circumference was used. Results : Prevalence of MS was significantly higher in the SLI group than the normal group. HCY was also significantly higher in the SLI group than the noraml, and the odds ratio (OR) for SLI, comparing high HCY level (${\geq}10{\mu}mol/L$) with low HCY level ($<10{\mu}mol/L$), was 3.64 (95% confidence interval (CI); 1.81-7.29, p<.0001). However, there was no correlation between MS and HCY in the SLI group. Prevalence of diabetes and hypertension (HT) was higher in the SLI group than the normal group, but there was no significant difference in blood lipids level between the SLI and normal groups. Of note, HT itself was enough to be an independent risk factor for SLI (OR; 4.58, 95% CI; 1.91-11.01, p=0.001). Body mass index, waist circumference, waist-hip ratio and visceral fat area were significantly higher in the SLI than normal group, and visceral fat area was enough to be an independent risk factor for SLI (OR; 2.41, 95% CI; 1.04-5.59, p=0.040). Conclusions : SLI is shown to have significant correlation with HCY and prevalence of MS, however there is no relationship between HCY and prevalence of MS in patients with SLI.

• Analytical Science and Technology
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• v.15 no.6
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• pp.534-539
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• 2002

We established an analytical method for the measurement of trace amounts of earthy/musty odorous geosmin (GSM) and 2-methylisoborneol (2-MIB) in water using GC/MS. Water samples were extracted with n-hexane (liquid-liquid extraction, LLE) and the extracts were measured by GC/MS. The extraction yields of the two compounds were tested to be ($87{\pm}8$)% and ($78{\pm}8$)%, respectively. The limits of quantitation (LOQs) of the two compounds by this method were greatly improved to ~0.3 ng/L. The analytical methods were applied to analyze water samples from several rivers in Korea and waters after water treatment processes. The highest levels of geosmin and 2-methylisoborneol in raw water from a river were measured to be ($4.2{\pm}0.4$) ng/L and ($44{\pm}4$) ng/L, respectively. The levels only slightly decreased to ($1.3{\pm}0.1$) ng/L and ($18{\pm}2$) ng/L even after water treatment, indicating that the odorous compounds were not properly removed by the treatment processes.

• 한국노년학
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• v.40 no.3
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• pp.511-530
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• 2020

The present study aimed to examine the moderating effects of marital satisfaction (MS) on the association between the number of chronic disease (CD) and depressive symptoms (DS) among ol der men and women. The 6th wave of the Korean Longitudinal Study of Ageing was utilized and the sample was married men (N=585) and women (N=460) aged 65 and over. Multiple regression analysis using SPSS WIN 25.0 and Process Macro was used to test moderating effects of MS. Control variables were age, education, household income, parent-child relationship satisfaction, self-rated health, cognitive function, current smoking status and CD of spouse. Resul ts from elderly men showed the moderating effect of MS was significant. Specifically, those with more CD were more likely to report higher level of DS in the low MS group. However, the effect of CD on DS was not significant in the high MS group. Results from elderly women showed the moderating effect of MS was not significant. This study showed the moderating effect of MS on the association between CD and DS differed by gender in later life. It suggests practical intervention to utilize the resources of spouses is in need to promote mentally healthy aging even though having chronically ill in later life.

• KSBB Journal
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• v.29 no.2
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• pp.124-130
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• 2014

Acer tegmentosum was a traditional Korean herbal medicine showing various pharmacological activities. In this work, A. tegmentosum were extracted with boiling water and then successively partitioned with dichloromethane, ethyl acetate, n-butyl alcohol (n-BuOH), and water. Salidoside, the target compound, was purified in n-BuOH phase using a chromatography method. For the analysis of salidoside, TLC and LC-MS were used as well as on-line screening $HPLC-ABTS^+$ assay with three different wavelength of 254, 280, and 320 nm. An amount of 1.34 g of salidoside were obtained in n-BuOH phase fromAcer tegmentosum was a traditional Korean herbal medicine showing various pharmacological activities. In this work, A. tegmentosum were extracted with boiling water and then successively partitioned with dichloromethane, ethyl acetate, n-butyl alcohol (n-BuOH), and water. Salidoside, the target compound, was purified in n-BuOH phase using a chromatography method. For the analysis of salidoside, TLC and LC-MS were used as well as online screening $HPLC-ABTS^+$ assay with three different wavelength of 254, 280, and 320 nm. An amount of 1.34 g of salidoside were obtained in n-BuOH phase from 3 kg of dry biomass. The on-line screening $HPLC-ABTS^+$ assay is rapid and efficient tool to search bioactivity from A. tegmentosum. 3 kg of dry biomass. The on-line screening $HPLC-ABTS^+$ assay is rapid and efficient tool to search bioactivity from A. tegmentosum.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.6
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• pp.59-66
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• 2005

This paper presents some features and statistics of electromagnetic pulses radiated from intracloud lightning discharges. The LabVIEW based-measurement system of time-dependent electromagnetic fields was constructed. The frequency bandwidth of the measuring system ranged from 300[Hz] to 1[MHz], and the response sensitivity was 2.78(mV/nT). The resolution and the maximum recording length of the data acquisition system were 12(bits) and 100[ms], respectively. In the electromagnetic pulses radiated from intracloud discharges, a pronounced bipolar pulse appeared with one or more fast pulses superimposed on the initial front part of the bipolar pulse. The mean duration of intracloud discharges was $1.05{\pm}0.32[ms]$, and an average of about 8 outburst pulses appeared for a period.