• Korean Journal of Applied Biomechanics
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• v.26 no.2
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• pp.167-174
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• 2016

Objective: The purpose of this study was to determine the interrelationship between ranges of motion of the knee and ankle joints on the sagittal plane and the attenuation magnitude of impact shock at high frequency (9~20 Hz) in the support phase during downhill running. Method: Fifteen male heel-toe runners with no history of lower extremity injuries were recruited for this study (age, $25.07{\pm}5.35years$; height, $175.4{\pm}4.6cm$; mass, $75.8{\pm}.70kg$). Two uniaxial accelerometers were mounted to the tuberosity of tibia and sacrum, respectively, to measure acceleration signals. The participants were asked to run at their preferred running speed on a treadmill set at $0^{\circ}$, $7^{\circ}$, and $15^{\circ}$ downhill. Six optical cameras were placed around the treadmill to capture the coordinates of the joints of the lower extremities. The power spectrum densities of the two acceleration signals were analyzed and used in the transfer function describing the gain and attenuation of impact shock between the tibia and the sacrum. Angles of the knee and ankle joints on the sagittal plane and their angle ranges were calculated. The Pearson correlation coefficient was used to test the relationship between two variables, the magnitude of impact shock, and the range of joint angle under three downhill conditions. The alpha level was set at .05. Results: Close correlations were observed between the knee joint range of motion and the attenuation magnitude of impact shock regardless of running slopes (p<.05), and positive correlations were found between the ranges of motion of the knee and ankle joints and the attenuation magnitude of impact shock in $15^{\circ}$ downhill running (p<.05). Conclusion: In conclusion, increased knee flexion might be required to attenuate impact shock during downhill and level running through change in stride or cadence while maintaining stability, and strong and flexible ankle joints are also needed in steeper downhill running.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.25 no.2
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• pp.89-94
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• 2014

Objectives : This study was conducted naturalistically in order to observe the long-term effects of attention-deficit hyperactivity disorder (ADHD) medications on growth rates among Korean school-aged boys with ADHD. Methods : Participants in the study were boys with ADHD aged 6 to 11 years who have taken ADHD medication, methylphenidate (extended release) or atomoxetine. They attended scheduled visits monthly or bimonthly for clinical assessment with measurement of height and weight. In this study, 35 boys with ADHD (mean age at baseline=$7.90{\pm}1.77$ years ; mean age at endpoint= $12.54{\pm}1.91$ years) were included, with a mean follow-up period of 4.64 years (${\pm}1.62$ years), ranging from 2 to 9.7 years. Height, weight, and body mass index (BMI) measurements were converted to "age-corrected Z-scores" using data from Growth Charts provided by the Korean Center for Disease Control and Prevention from 2007. Results : Age-corrected endpoint growth parameters (height, weight, BMI Z-scores) did not differ significantly from the baseline values (height t=0.027 ; weight t=-0.61 ; BMI t=-1.86, in paired t-test). Especially high correlation was observed between the baseline and endpoint height Z-scores (r=0.876, p<.001), for which the coefficient of determination $r^2$ was 0.767, meaning that the amount of variability in endpoint height Z-scores explained by the baseline height Z-scores was 76.7%. Conclusion : Our results suggested that the long-term effects of ADHD medications on growth parameters to be tolerable in Korean school-aged boys with ADHD.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5637-5642
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• 2012

Objective: Gastric cancer (GC) is one of the most common malignancies and its mortality ranks third among all cancers in China. We previously noted that XRCC1 Arg194Trp was associated with GC risk in Western China in a study on XRCC1 Arg194Trp and ADPRT Val762Ala. We aimed to further explore the association of these polymorphisms with risk of the noncardia subtype. Methods: We enrolled 176 noncardia GC patients and 308 controls from four hospitals and a community between October 2010 and August 2011. Genotyping was performed in a 384-well plate format on the Sequenom MassARRAY platform. A self-designed questionnaire was utilized to collect epidemiological data from the subjects regarding demographic factors and potential risk factors. Results: Subjects were aged $56.8{\pm}11.8$ (mean ${\pm}$ standard deviation) and $57.6{\pm}11.1$ years in the case and control groups, respectively. Individuals carrying the XRCC1 Trp/Trp or Arg/Trp variant genotype were at significantly increased risk of noncardia GC (adjusted OR, 1.48; 95% CI, 1.00-2.17), after adjustment for family history of cancer, drinking, and smoking. The increased risk of XRCC1 Arg194Trp variant genotype was more pronounced among subjects below 60 years old (adjusted OR, 1.78; 95% CI, 1.07-2.96), compared to older individuals. ADPRT Val762Ala variants (Ala/Ala or Val/Ala) were not associated with noncardia GC (adjusted OR, 1.03; 95% CI, 0.69-1.54). Conclusions: Our study suggests that XRCC1 Arg194Trp is a genetic susceptibility factor for developing noncardia GC in Han Chinese in Western China. In particular, individuals with the XRCC1 Arg194Trp variant genotype are at increased risk for GC below 60 years old.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.5
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• pp.921-935
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• 2016

This research analyzed the manual performance of firefighting protective gloves on global markets in order to suggest an evaluation method for firefighting protective gloves wearing comfort. We collected 13 types of firefighting gloves from domestic and international markets (7 types from Korea, 3 types form Europe, 2 types from the U.S and 1 type from Japan). We set the Don-Doff test as a basal requirement for moving toward to further manual performance tests that consist of: ASTM dexterity test, Minnesota dexterity test, Bennett hand tool test and ASTM torque test. All gloves were evaluated in dry and wet conditions, we included eight current male firefighters ($43.4{\pm}7.0yr$ in age, $173.1{\pm}4.4cm$ in height, $79.9{\pm}9.2kg$ in body mass) for the tests. Four gloves (1 Korea, 1 U.S, 1 Germany, and 1 Japan) out of thirteen firefighting gloves passed the Don-Doff test and had great subject preferences. There was no significant difference between dry and wet conditions on the ASTM dexterity test, Minnesota dexterity test, Bennett hand tool test and ASTM torque test. However, Japanese gloves had the greatest score and showed 3-4 times faster completion time on the ASTM dexterity test (p<.05), 1.2-1.5 times faster on the Minnesota dexterity test (p<.05), as fast as the bare hand on Bennett hand tool test (p<.05), and greater performance on the ASTM torque test compared to bare hand. In conclusion, Don-Doff test in wet conditions should be the first step for a mobility evaluation of domestic firefighting protective gloves; subsequently, a comprehensive test assorting ASTM, Minnesota, and Bennett test should be developed as a second step. The current ASTM torque test can be adopted as a third step. This three-step-method for evaluating firefighting protective glove mobility can be expected to expand into surveys of other safety gloves in Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.5
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• pp.485-500
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• 2016

We examined acidity state of inorganic aerosol and oxidation state of organic aerosol by High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) at Baengnyeong Super site from Jan 2012 to Dec 2013. Additionally, we carried out the analysis for the aerosol component group of organic matter ($C_xH_y$, $C_xH_yO_1$, $C_xH_yO_z$, $C_xH_yO_zN_p$) and elemental composition to calculate H/C, O/C, N/C, OM/OC and identify the oxidation state. The aerosol chemical composition in this study is dominated by sulfate ($SO_4{^{2-}}$), nitrate ($NO_3{^-}$) plays a smaller role in aerosol acidity. Ammonium ($NH_4{^+}$) was found in a formation of $(NH_4)_3H(SO_4)_2$. However, the binding formations of $NH_4NO_3$ and $NH_4Cl$ increase in the winter. $C_xH_yO_1$ indicating the oxidized state of $PM_{1.0}$ has the highest ratio of 41% while $C_xH_y$ indicating the non-oxidized state has a lower ratio of 36%, meaning that the oxidation level of $PM_{1.0}$ in Baengnyeong Island is high. The ratio between H/C and O/C was 1.33 and 0.78 respectively, showing the characteristic of LV-OOA (Low volatility-Oxygenated Organic Aerosol). Acidic and oxidized aerosols sampled during this field study were largely anthropogenic in origin from Chinese continent and photochemically aged.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.3
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• pp.264-274
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• 2013

This study investigates long-term trends and characteristics of aerosol light scattering coefficient at Seoul and Baengnyeongdo in order to understand aerosol optical and radiative properties around Korea. The analysis period is limited to one year of 2011. First, the aerosol scattering coefficients (${\sigma}_{sp}$) of both sites show strong linear dependence on the $PM_{2.5}$ mass concentrations with significant correlations between both. Further, correlations and sensitivity between ${\sigma}_{sp}$ and $PM_{2.5}$ increase with relative humidity, implying both relationships are strongly dependent upon moisture amounts in the atmosphere. This study applied 3-step careful quality control procedures to the analysis of ${\sigma}_{sp}$ for the insurance of data confidence. For the relationship analysis of extinction coefficients (${\sigma}_{ext}$) to visibility and aerosol optical depth, ${\sigma}_{sp}$ observed at 3 p.m. have been used with help of aerosol absorption coefficients (${\sigma}_{ap}$) in order to remove its dependence upon relative humidity, and also those of rainy period have been excluded. As expected, ${\sigma}_{ext}$ estimated are inversely proportional to visibility observation by eye. Finally, aerosol extinction coefficients have been vertically integrated with an assumption of nearly well-mixed within an e-folding height to determine aerosol optical depth, and compared with those retrieved from sunphotometer. The results show a reasonable agreement in spite of an inherent difference of each definition. We expect these findings would help to eventually understand aerosol radiative forcing and its effect on the regional climate change around Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.4
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• pp.411-423
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• 2017

The spacial potential source contribution function (PSCF) method was utilized by considering topography and height of back trajectories based on the measurement of organic typo matter (OM), $NO_3{^-}$, $SO{_4}^{2-}$, and $NH_4{^+}$ at the Baegryungdo Super Site ($37^{\circ}57^{\prime}N$, $124^{\circ}37^{\prime}E$, 135 m a.s.l. (above sea level)) for three selected periods (i.e., January~April, May~August, and September~December) in 2013. The PSCF were calculated on the contributions of trans-boundary transport to the hourly mean concentrations using a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). The cluster analysis using back trajectories was performed to identify the major airflows to the sampling site. The upper atmosphere in the Tianjin area of China and the lower atmosphere in the western coast area of Korea can be the major source of trans-boundary pollution to the sampling site during January~April resulted from PSCF. The area in Lianyungang-city and Liaoning-sheng, China can be responsibile for the nitrogen related secondary compounds during May~August, and Shandong Peninsula in China is the major source area during September~December. In addition, relationships between the cluster analysis of back trajectories and PSCF were investigated for the statistically significance level for the source areas.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.207-210
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• 2013

In this study, matured silkworm hemolymph was studied for inhibitory effect on melanin formation, tyrosinase activities. A matured silkworm hemolymph mass purification method was developed and some of suppressing melanin formation effects were investigated, too. As a result, the advanced purification method was higher in yield rate than existing one by 53%. A free radical scavenging activity of hemolymph was higher than sericin on the market($IC_{50}$, $202.9{\pm}33.1$) and lower than vitamin C($0.57{\pm}0.02$) by $6.4{\pm}0.3{\mu}g/m{\ell}$. An inhibitory effect on melanin synthesis was higher in hemolymph compared to Morus bark and arbutin by 9.15% and 11.56%, respectively. An inhibitory effect on tyrosinase activity was higher in hemolymph than Morus bark and lower than arbutin. Effect of hemolymph $45{\mu}g/m{\ell}$ on suppressing of tyrosinase was almost 90%. Thus, these results suggest that hemolymph of matured silkworm may have beneficial properties as a material for cosmetics.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.539-547
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• 2013

This study investigates the change of chemical components, antioxidant and antimutagenic activity in Glycyrrhiza uralensis Fischer stems and leaves (GU) by the various processing methods, as follows: fresh (GU-1), dried under the shade (GU-2), blanched (GU-3), roasted 3 times (GU-4), roasted 4 times (GU-5). The components have been identified and quantified through the use of gas chromatograph-mass spectrometry (GC-MS). At results, cis-1,3-dimethyl-2-methylenecyclohexaneat at 19.7 min and n-hexadecanoic acid at 21.5 min were detected in five kinds of extract. 3-O-Methyl-D-fructose at 17.8 min was observed in four extracts except in GU-1 and aminopyrazine at 19.8min was observed in four extracts except in GU-4. The total phenolics contents was high in GU-4(3.38 g/100 g). ABTS radical scavenging was high in GU-5($EC_{50}$, 0.57 ug) and DPPH radical scavenging was high in GU-4($EC_{50}$, 2.66 ug). The extracts of GU-3, GU-4, and GU-2 were most potent in anti-mutagenicity activity against 1-NP, Trip-P-1, and Trip-P-2, respectively. GU-3 and GU-4 also showed most potent effect of anti-mutagenicity on 2-AA and AFB1, respectively.

• Journal of the Korean Dietetic Association
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• v.10 no.2
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• pp.205-217
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• 2004

This study was carried out to provide information on the effect of nutrition education program for diabetic patients at the Guri City's Public Health Center. Subjects of this study were 31 persons(male 7, female 24) who attended all courses of "2002 Diabetes Education Class". They were indicated as the 'education group'(EG). Eating and living habits of EG were investigated before the education. EG's weight and blood glucose (post prandial 2 hours, PP2) were examined as well. EG's PP2 reduction was compared with a 'control group'(CG) who didn't join any course in that class. All of the subjects were non-insulin-dependent diabetes mellitus(NIDDM) patients. EG's average age was 62.4$\pm$8.8. Before taking the course, EG's PP2 was 251.5$\pm$29.6mg/dl, and body mass index(BMI) was 26.3$\pm$2.3 on average. Most of them were stressed out from their daily lives and usually had no exercise. Most people of EG ate meals rapidly and liked sweet and fatty foods. After the course of training, EG's weight and BMI before the training were not decreased significantly. However, all of the EG's PP2s, which were measured 4 times(before the meal at the special lunch session, after 2 hours at this meal, after 2 weeks and 4 weeks dietary assembly), were decreased in comparison with the PP2 which was checked prior to joining the training. EG's average PP2 was more reduced than CG's one. In addition, all groups' PP2s were decreased for 8 weeks. After all, this nutritional education at the public health center was effective in glycemic control for diabetes mellitus patients. Especially, when the dietary assembly as practical training was included in the educational process, the patient's dietary intake and PP2 was improved more effectively. Therefore, this study suggests that nutrition work at public health centers is necessary for the Health Promotion Policy.