• Corrosion Science and Technology
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• v.22 no.1
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• pp.30-35
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• 2023

Hafnium nitride (HfN) thin films were fabricated by mid-frequency magnetron sputtering (mfMS) and direct current magnetron sputtering (dcMS) and their mechanical and structural properties were compared. In particular, changes in the HfN film properties were observed by changing the pulse frequency of mfMS between 5 kHz, 15 kHz, and 30 kHz. The crystalline structure, microstructure, 3D morphology, and mechanical properties of the HfN films were compared by x-ray diffraction, field-emission scanning electron microscopy, atomic force microscopy, and nanoindentation tester, respectively. HfN film deposited by mfMS showed a smoother and denser microstructure as the frequency increased, whereas the film deposited by dcMS showed a rough and sloppy microstructure. A single δ-HfN phase was observed in the HfN film made by mfMS with a pulse frequency of 30 kHz, but mixed δ-HfN and HfN_0·4 phases were observed in the HfN film made by dcMS. The mechanical properties of HfN film made by mfMS were improved compared to film made by dcMS.

• Korean Journal of Pharmacognosy
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• v.49 no.1
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• pp.76-83
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• 2018

A traditional herbal formula, Gyeji-tang has been used to treat the early colds, headache, chills, and fever in Asian countries. In this study, we were performed simultaneous determination of the 14 bioactive marker compounds, gallic acid, spinosin, paeoniflorin, albiflorin, liquiritin apioside, liquiritin, 6'''-feruloylspinosin, liquilitigenin, coumarin, cinnmamic acid, benzoylpaeoniflorin, cinnamaldehyde, glycyrrhizin, and 6-gingerol in Gyeji-tang using an ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS/MS). Analytical column was used a Waters Acquity UPLC BEH $C_{18}$ analytical column ($2.1{\times}100mm$, $1.7{\mu}m$) and maintained at $45^{\circ}C$ with a flow rate of 0.3 mL/min. The mobile phase consists of 0.1% (v/v) formic acid in water and acetonitrile with gradient elution. The MS analysis was conducted using multiple reaction monitoring in the positive and negative modes by a Waters ACQUITY TQD LC-MS/MS system. The calibration curves of 14 bioactive marker compounds showed linearity with correlation coefficients ${\geq}0.9798$. The limits of detection and quantification values were in the range of 0.11-6.66 ng/mL and 0.34-19.99 ng/mL, respectively. As a result of the analysis using the established LC-MS/MS method, the amounts of tested 14 compounds in the lyophilized Gyeji-tang sample were detected up to $85.7{\mu}g/g$. These results may be useful for quality assessment of a traditional herbal formulas.

• Journal of Nutrition and Health
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• v.41 no.6
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• pp.510-517
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• 2008

This study was conducted to investigate the prevalence of metabolic syndrome(MS) and characteristics of nutrient intake in MS subjects by gender and age. The subjects were 957(447 men and 510 women) who visited medical center for regular medical check-up. The diagnosis of MS subjects was adapted from NCEP-ATPIII with blood glucose, cholesterol, triglycerides, and blood pressure and Aisa-Pacific definition with waist-circumference. Anthropometric and biochemical measurements were practiced, then the nutrient intake analysis was assessed through the 24-hour recall method. The MS prevalence of all subjects was 10.3% in average -17% in men and 4.5% in women, respectively. The energy intake in MS group was 2,047.1 kcal and 1,699.5 kcal for normal group, showing significantly higher in MS compared to normal subjects. For intakes of animal fat, cholesterol, and sodium, MS group were significantly higher than normal group. In respect of gender, men subjects of MS group showed significantly higher nutrient intakes than normal group for energy, fat, and cholesterol. Women subjects of MS group showed higher intakes for energy, carbohydrate, and protein. For 30s, MS group showed higher intakes of energy, animal fat, and cholesterol than normal group. Fat and cholesterol for 40s and energy, carbohydrate, vegetable fat for 50s, MS group showed significantly higher intakes than normal group. In summary, MS group showed higher intakes of energy, animal fat, cholesterol, and sodium than normal group.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.8-14
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• 2008

This study was performed to establish analysis methods, and evaluated for grayanotoxin in domestic/foreign honey and wild honey. The molecular weight of grayanotoxins I, II and III, excluding grayanotoxin III that has been commercialized, were analyzed by LC-MS/MS. Then, the molecular structure of grayanotoxins I and II were analyzed by NMR. A total 111 samples (25 Korean honey, 21 Korean wild honey, 13 Korean honeycomb honey, 44 foreign honey, 8 foreign wild honey) were examined to determined whether or not each sample contained grayanotoxins I, II, and III. The honey samples were mixed with methanol and loaded into a tC18 cartridge, the filtrate was diluted with water, and the mixture was then analyzed by ESI triple-quadrupole LC-MS/MS. Grayanotoxins were only found in the foreign wild honey and were not detected in Korean honey, Korean honeycomb honey, or Korean wild honey. Three of the samples contained grayanotoxin I, II, and III, and one sample contained only grayanotoxins I and III. The lowest level for grayanotoxin I was 3.13 ${\pm}$ 0.00 mg/kg, and the highest level was 12.93 ${\pm}$ 0.01 mg/kg. The levels of grayanotoxin II were 0.84 ${\pm}$ 0.01 mg/kg, 0.92 ${\pm}$ 0.00 mg/kg and 1.08 ${\pm}$ 0.01 mg/kg, respectively. The lowest level of grayanotoxin III was 0.25 ${\pm}$ 0.01 mg/kg and the highest level was 3.29 ${\pm}$ 0.74 mg/kg. Through this study, safety management for foreign wild honey has been enabled.

• Korean Journal of Cognitive Science
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• v.23 no.3
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• pp.323-348
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• 2012

Three experiments were conducted to explore the interaction of personal pronoun (e.g. 'I' and 'you') and emotional evaluation (e.g. positive and negative) using time-course (e.g. SOA 500-1000ms) and multi-task approaches (e.g. lexical decision task and primed naming task). In Experiment 1, Participants were presented personal pronoun as primes at SOA 1000ms and were asked to response emotional words which were differed in emotional attributes. The results showed that the interaction effects of personal pronoun and emotional words were found. In Experiment 2, Participants were presented personal pronoun as primes at SOA 1000ms and were asked to response emotional words which were differed in emotional attributes. The results showed that no effects were found. In Experiment 3, Participants were presented personal pronoun as primes at SOA 500ms and were asked to pronounce emotional words which were differed in emotional attributes. The results showed that the interaction of personal pronoun and emotional words were found. The results of 3 experiments were discussed from a point of view of dynamic processes of social cognition.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3727-3734
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• 2012

An analytical method has been developed for the rapid determination of perfluorinated compounds (PFCs) in human serum samples. The extraction and purification of PFCs from human serum were performed by the modified method of previous report. Ten PFCs were rapidly separated within 3.3 min by C18-monolithic column liquid chromatography (LC) and detected by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) in negative ion mode. The runtime of PFCs on monolithic column LC was up to 4-fold faster than that on conventional column LC. The effect of triethylamine (TEA) to the mobile phase has investigated on the overall MS detection sensitivity of PFCs in ESI ionization. Quantification was performed by LC-MS/MS in multiple-ion reaction monitoring (MRM) mode, using $^{13}C$-labeled internal standards. Method validation was performed to determine recovery, linearity, precision, and limits of quantification, followed by, the analysis of a standard reference material (SRM 1957 from NIST). The overall recoveries ranged between 81.5 and 106.3% with RSDs of 3.4 to 16.2% for the entire procedure. The calibration range extended from 0.33 to 50 $ng\;mL^{-1}$, with a correlation coefficient ($R^2$) greater than 0.995 and the limits of quantification with 0.08 to 0.46 $ng\;mL^{-1}$. This approach can be used for rapid and sensitive quantitative analysis of 10 PFCs in human serum with high performance and accuracy.

• Journal of Adhesion and Interface
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• v.20 no.3
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• pp.102-109
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• 2019

The material constitution of multi-layered thin film coated on the PET base film was analyzed using ATR FT-IR and pyro GC/MS combination. The cross section of the film was acquired by cracking the film after dipping in liquid nitrogen and was observed using optical microscope. Total thickness of the coated film was $70{\mu}m$ and three layers were observed. Since each layers were too thin to analyze directly except the surface layer, analyzable area of each layers were exposed by using a proper solvent and were investigated using ATR FT-IR and pyro GC/MS. Results shows that three layers were commonly consisted of urethane-acrylate copolymers. Also, inorganic and/or metal inclusions detected by XPS and SEM-EDAX were exhibited by nano size $SiO_2$ particles in layer(1) and aluminum flakes in layer(2).

• Investigative Magnetic Resonance Imaging
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• v.3 no.2
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• pp.154-158
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• 1999

Purpose : The purpose of this study was to find the optimum TE value for enhancing $T_2^{*}$ weighting effect and minimizing the SNR degradation and to compare the BOLD effects according to the changes of TE in 1.5T and 3.0T MRI systems. Materials and Methods : Healthy normal volunteers (eight males and two females with 24-38 years old) participated in this study. Each volunteer was asked to perform a simple finger-tapping task (sequential opposition of thumb to each of the other four fingers) with right hand with a mean frequency of about 2Hz. The stimulus was initially off for 3 images and was then alternatively switched on and off for 2 cycles of 6 images. Images were acquired on the 1.5T and 3.0T MRI with the FLASH (fast low angle shot) pulse sequence (TR : 100ms, FA : $20^{\circ}$, FOV : 230mm) that was used with 26, 36, 46, 56, 66, 76ms of TE times in 1.5T and 16, 26, 36, 46, 56, 66ms of TE in 3.0T MRI system. After the completion of scan, MR images were transferred into a PC and processed with a home-made analysis program based on the correlation coefficient method with the threshold value of 0.45. To search for the optimum TE value in fMRI, the difference between the activation and the rest by the susceptibility change for each TE was used in 1.5T and 3.0T respectively. In addition, the functional $T_2^{*}$ map was calculated to quantify susceptibility change. Results : The calculated optimum TE for fMRI was $61.89{\pm}2.68$ at 1.5T and $47.64{\pm}13.34$ at 3.0T. The maximum percentage of signal intensity change due to the susceptibility effect inactivation region was 3.36% at TE 66ms in 1.5T 10.05% at TE 46ms in 3.0T, respectively. The signal intensity change of 3.0T was about 3 times bigger than of 1.5T. The calculated optimum TE value was consistent with TE values which were obtained from the maximum signal change for each TE. Conclusion : In this study, the 3.0T MRI was clearly more sensitive, about three times bigger than the 1.5T in detecting the susceptibility due to the deoxyhemoglobin level change in the functional MR imaging. So the 3.0T fMRI I ore useful than 1.5T.

• The Korean Journal of Rehabilitation Nursing
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• v.11 no.2
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• pp.90-98
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• 2008

Purpose: The purpose of this study was to examine the cognitive function and degree of dementia patient by doing clock drawing test and to explore the relationship among other dementia screening test. Method: The study subjects were 94 dementia in patients department. The data was collected by face to face interview by clinical psychologist from January 2007 to February 2008. The tools were Clock Drawing Test, K-MMSE, K-3MS and CDR Scale. Results: 1) The average score of CDT was 5.13 (2.54), of K-MMSE was 20.53 (4.85), of K-3MS was 61.66 (16.46), and of CDR was 1.2 (.72), those scores showed dementia. 2) There was a statistically the significant difference in CDT (F=2.83, p=.043) and CDR (F=2.00, p=.008) by age. CDT has shown the differences by gender (t=-2.42, p=.018) and education (F=7.66, p=.000). 3) There were significant relationships between CDT and K-MMSE (r=-.294. p=.004), K-3MS (r=-.335, p=.001), and CDR (r=.286, p=.008). Conclusion: It is believed that using CDT which measures the visuospatial ability of dementia patients and K-MMSE which assesses an ability of language and orientation and K-3MS at the same time helps examining the beginning and the progressive degree of dementia more easily and objectively.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.104-109
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• 2007

A multiplex polymerase chain reaction (PCR) method was developed to simultaneously detect three varieties of genetically modified (GM) canola. The construct-specific primers were used to distinguish the following three varieties of GM canola; GT73, MS8xRF3, and T45, using multiplex PCR. The FatA (fatty acyl-ACP thioesterase) gene was used as an endogenous canola reference gene in the PCR detection. The primer pair Canendo-FIR containing a 105 bp amplicon was used to amplify the FatA gene and no amplified product was observed in any of the 15 different plants used as templates. The GT73-KHUF1/R1 primer recognized the 3'-flanking region of GT73, resulting in an amplicon of 125 bp. The Barstar-F1/MS8xRF3-R primer recognized the junction region of bars tar and the NOS terminator introduced into MS8xRF3, resulting in a 162 bp amplicon, and the T45-F2/R2 primer recognized the junction region of PAT and the 35S terminator introduced into T45, resulting in an amplicon of 186 bp. This multiplex PCR allowed for the detection of construct-specific targets in a genomic DNA mixture of up to 1% GM canola containing GT73, MS8xRF3, and T45.