• Archives of Pharmacal Research
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• v.26 no.4
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• pp.330-337
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• 2003

The effect of sixteen excipients on the transport of recombinant human epidermal growth factor (rhEGF) across Caco-2 cell monolayers was examined at $37^{\circ}C$. The apparent apical to basolateral (A-B) permeability ($P_{app}$) of 30 $\mu$ M rhEGF was $8.15\times 10^{-7}$ cm/sec, indicative of a poor level of absorption in the GI tract. The Papp was 1.7- and 6.3-fold greater than the $P_{app}$ in the basolateral to apical (B-A) direction and the A-B permeability of mannitol, respectively, and decreased dramatically to a negligible level at $4^{\circ}C$, consistent with a receptor mediated transcytosis of rhEGF. The stability of rhEGF was very poor, undergoing more than 85% degradation in 2 h in the transport medium at $37^{\circ}C$. A significant increase in the $P_{app}$ could be achieved by the addition of certain excipients, as exemplified by 23, 21, 20 and 16-fold increases, in the presence of sodium taurochenodeoxycholate (NaTCDC), sodium taurodeoxycholate (NaTDC), sodium glycodeoxycholate (NaGDC) and sodium laurylsulfate (SLS) (all at a concentration of 1 % w/v), respectively. A significant increase in stability could also be achieved by the addition of some of the excipients, as represented by 1 % SLS, which nearly completely stabilized the rhEGF. Unfortunately, however, an increase in the $P_{app}$ of rhEGF could not be achieved without a simultaneous and extensive decrease in the integrity of the cell membranes. Thus, more efficient excipients, that specifically enhance the permeation of rhEGF and do not alter the membrane integrity, should be pursued in order to safely enhance the permeation of rhEGF.

• The Journal of Korean Physical Therapy
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• v.21 no.3
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• pp.87-93
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• 2009

Purpose: TThis study examined the effect of repetitive magnetic stimulation (RMS) on the viability and proliferative response of human adipose tissue-derived stromal cells (hATSCs) in vitro. Methods: The hATSCs were cultured primarily from human adipose tissue harvested by liposuction and incubated in a $37^{\circ}C$ plastic chamber. The cells were exposed to a repetitive magnetic field using a customized magnetic stimulator (Biocon-5000, Mcube Technology). The RMS parameters were set as follows: repetition rate=10Hz, 25Hz (stimulus intensity 100%= 0.1 Tesla, at 4cm from the coil), stimulated time= 1, 5, and 20 minutes. Twenty four hours after one application of RMS, the hATSCs were compared with the sham stimulation, which were kept under the same conditions without the application of RMS. The cells were observed by optical microscopy to determine the morphology and assessed by trypan blue staining for cell proliferation. The apoptosis and viability of the hATSCs were also analyzed by fluorescence-activated cell sorting (FACS) analysis of Annexin V and MTT assay. Results: After RMS, the morphology of the hATSCs was not changed and the apoptosis of hATSCs were not increased compared to the sham stimulation. The viability of the cells was similar to the cells given the sham stimulation. Interestingly, the level of hATSC proliferation was significantly higher in all RMS groups. Conclusion: The application of RMS may not cause a change in morphology and viability of hATSCs but can increase the level of cell proliferation in vitro. RMS might be useful as an adjuvant tool in combination with stem cell therapy without adverse effects.

• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.95-103
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• 2011

We have investigated pretreatment of waste wood using milling refinery combined with poping method, which can save energy for pretreatment and enzyme loading for enzymatic hydrolysis. The chemical analysis of holocellulose of non and popping treated waste wood showed 65.9% and 58.8%, and the lignin, organic extracts and ash were increased by 3%, 4% and 0.7% after pretreatment, respectively. The reducing sugar yields of pretreated waste wood were increased four times more than non-pretreated one and the synergistic effect of cellulase and xylanase were evaluated compare with individual enzyme treatment. Especially, enzyme cocktail (cellulase 50 U and xylanase 50 U) treatment was very efficient in 1% substrate (50 mg). Also, glucose and xylose conversion rate of pretreated waste wood by GC analysis were 45.9% and 38.7%, respectively.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.57-63
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• 2012

This paper analyzes phenolic compounds, carbon isotopes, and sugar components of whiskys based on the maturation period. For this, the paper considers a total of 40 whiskys(mainly imports) distributed in Korea. It is important to analyze the presence phenolic compounds(e.g., furfural, syringaldehyde, vanillin, syringic acid, and vanillic acid) because these are found only in whiskys ripened in oak. The results indicate that the total content of phenolic compounds increased with the increase in the storage period regardless of the type of whisky. In terms of vanillin/syringaldehyde(V/S), Scotch whiskys had 0.4~0.5; American whiskies, 0.30~0.34; and Canadian whiskies, 0.31~0.33. In terms of Scotch whiskys, Macallan had 0.25~0.34, making it unique among Scotch whiskys. In terms of the ratio of carbon isotopes, there were clear differences between malt Scotch whiskys, blended Scotch grain whiskys, American whiskys, and Canadian whiskys: -23.4~ -24.3, -16.8~-21.0, -11.0~-11.5 and -9.5~13.9, respectively. In addition, malt Scotch whiskys contained 40~230 $mg/{\ell}$ of fructose; blended Scotch whiskys, 20~120 $mg/{\ell}$; American whiskys, 50~70 $mg/{\ell}$; and Canadian whiskys, 20~100 $mg/{\ell}$, demonstrating that the fructose content of single-malt whiskys was twice the average fructose content. On the other hand, malt Scotch whiskys contained 30~170 $mg/{\ell}$ of glucose; blended Scotch whiskys, 20~120 $mg/{\ell}$; American whiskys, 20~30 $mg/{\ell}$; and Canadian whiskys, 10~110 $mg/{\ell}$, demonstrating that the glucose content of single-malt whiskys exceeded the average glucose content. This study's results can be used as a database of classification for whiskys based on the fermentation of raw ingredients and the period of maturation for distinguishing between different types of whiskys. In addition, the results can facilitate the verification of genuine whiskys by allowing for the identification of different types of whiskys based on the period of maturation.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.312-319
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• 1996

Oyster (Crassostrea virginica) and Weakfish (Cynoscion regalis) were stored at 6, 0, -4 and -20$^{\circ}C$ for up to 45 days and examined for changes in microflora. Aerobic plate counts (incubated at 21$^{\circ}C$) were performed at selected times during storage and 495 isolates (255 isolates from oyster and 240 isolates from Weakfish) were randomly selected from the plates during the storage. Before the storage of the fishes, viable counts of oyster were 4.9${\times}$10$\^$5/ CFU/g of meat and those of Weakfish were 1.5${\times}$10$^4$ CFU/cm$^2$of skin. Microflora of oyster before storage, the major isolates identified as Pseudomonas spp. (67%) and Vibrio spp. (20%). Pseudomonas ll1/1V-H and Flavobacterium/Cytophaga were predominant genus in the microflora of oyster during cold storage at 6, 0, -4 and -20$^{\circ}C$. The composition of the microflora of Weakfish before storage, Acinetobacter (40%) and Moraxella (33%) were the major species, with Pseudomonas and Vibrio constituting a small percentage of the total isolates. The microflora shifted to predominantly Pseudomonas spp. during storage at 6. 0 and -4$^{\circ}C$, making up from 60 to 100％ of isolated strains. During frozen storage, the percentage of isolates identified as Mnraxella increased to 40-60% of the total isolates. During cold storage, halophilic bacteria (Pseudomonas lII/IV-H and Vibrio) were predominant in oyster while nonhalophilic bacteria (Pseudomonas III/IV-NH and Moraxella) were predominant in Weakfish. Vibrio spp. were higher in oyster than in Weak fish. Listeria spp. were not isolated but unidentified ${\beta}$-hemolytic bacteria were islolated from both of the fishes during cold storage.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.32.1-32.1
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• 2017

To dynamically and chemically understand how filaments, dense cores, and stars form under different environments, we are conducting a systematic mapping survey of nearby molecular clouds using the TRAO 14 m telescope with high ($N_2H^+$ 1-0, $HCO^+$ 1-0, SO 32-21, and $NH_2D$ v=1-0) and low ($^{13}CO$ 1-0, $C^{18}O$ 1-0) density tracers. The goals of this survey are to obtain the velocity distribution of low dense filaments and their dense cores for the study of their origin of the formation, to understand whether the dense cores form from any radial accretion or inward motions toward dense cores from their surrounding filaments, and to study the chemical differentiation of the filaments and the dense cores. Until Feb. 2017, the real OTF observation time is 460 hours. We have almost completed mapping observation with four molecular lines ($^{13}CO$ 1-0, $C^{18}O$ 1-0, $N_2H^+$ 1-0, and $HCO^+$ 1-0) on the five regions of molecular clouds (L1251 of Cepheus, Perseus west, Polaris south, BISTRO region of Serpense, California, and Orion B). The maps of a total area of $7.38deg^2$ for both $^{13}CO$ and $C^{18}O$ lines and $2.19deg^2$ for both $N_2H^+$ and $HCO^+$ lines were obtained. All OTF data were regridded to a cell size of 22 by 22 arcseconds. The $^{13}CO$ and $C^{18}O$ data show the RMS noise level of about 0.22 K and $N_2H^+$ and $HCO^+$ data show about 0.14 K at the velocity resolution of 0.06 km/s. Additional observations will be made on some regions that have not reached the noise level for analysis. We are refining the process for a massive amount of data and the data reduction and analysis are underway. This presentation introduces the overall progress from observations to data processing and the initial analysis results to date.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.3
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• pp.43-49
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• 2010

Direct printing technology is an attractive metallization method, which has become immerging as "Green technology" to the conventional photolithography, on account of low cost, simple process and environment-friendliness. In order to commercialize the printed electronics in industry, it is essential to evaluate the electrical properties of conductive circuits using direct printing technology. In this contribution, we focused on the electrical characteristics of inkjet-printed circuits. A Cu nanoink was inkjet-printed onto a Bisaleimide triazine(BT) substrate with parallel transmission line(PTL) and coplanar waveguide(CPW) type, then was sintered at $250^{\circ}C$ for 30 min. We calculated the resistivity of printed circuits through direct current resistance by the measurement of I-V curve: the resistivity was approximately 0.558 ${\mu}{\Omega}{\cdot}cm$ which is about 3.3 times that of bulk Cu. Cascade's probe system in the frequency range from 0 to 30 GHz were employed to measure the Scattering parameter(S-parameter) with or without a gap between the substrate and the probe station chuck. The result of measured S-parameter showed that all printed circuits had over 5 dB of return loss in the entire frequency range. In the curve of insertion loss, $S_{21}$, showed that the PTL type circuits had better transmission of radio frequency (RF) than CPW type.

• Journal of Korean Dental Science
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• v.10 no.1
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• pp.10-21
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• 2017

Purpose: The purpose of this study was to investigate the electrochemical characteristics of nanotubular Ti-25Nb-xZr ternary alloys for dental implant materials. Materials and Methods: Ti-25Nb-xZr alloys with different Zr contents (0, 3, 7, and 15 wt.%) were manufactured using commercially pure titanium (CP-Ti), niobium (Nb), and zirconium (Zr) (99.95 wt.% purity). The alloys were prepared by arc melting in argon (Ar) atmosphere. The Ti-25Nb-xZr alloys were homogenized in Ar atmosphere at $1,000^{\circ}C$ for 12 hours followed by quenching into ice water. The microstructure of the Ti-25Nb-xZr alloys was examined by a field emission scanning electron microscope. The phases in the alloys were identified by an X-ray diffractometer. The chemical composition of the nanotube-formed surfaces was determined by energy-dispersive X-ray spectroscopy. Self-organized $TiO_2$ was prepared by electrochemical oxidation of the samples in a $1.0M\;H_3PO_4+0.8wt.%$ NaF electrolyte. The anodization potential was 30 V and time was 1 hour by DC supplier. Surface wettability was evaluated for both the metallographically polished and nanotube-formed surfaces using a contact-angle goniometer. The corrosion properties of the specimens were investigated using a 0.9 wt.% aqueous solution of NaCl at $36^{\circ}C{\pm}5^{\circ}C$ using a potentiodynamic polarization test. Result: Needle-like structure of Ti-25Nb-xZr alloys was transform to equiaxed structure as Zr content increased. Nanotube formed on Ti-25Nb-xZr alloys show two sizes of nanotube structure. The diameters of the large tubes decreased and small tubes increased as Zr content increased. The lower contact angles for nanotube formed Ti-25NbxZr alloys surfaces showed compare to non-nanotube formed surface. The corrosion resistance of alloy increased as Zr content increased, and nanotube formed surface showed longer the passive regions compared to non-treatment surface. Conclusion: It is confirmed that corrosion resistance of alloy increased as Zr content increased, and nanotube formed surface has longer passive region compared to without treatment surface.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.5
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• pp.21-28
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• 2007

In this paper, in order to derive the two-dimensional field effect of n-InAlAs/InGaAs HEMTs, we suggested analytical model by solving the two-dimensional Poisson's equation in both InAlAs and InGaAs regions by taking into account the longitudinal field variation, field-dependent mobility, and the continuity condition of the channel current flowing within the quantum well shaped channel. Derived expressions for long and short channel devices would be applicable to the entire operating regions in a unified manner. Simulation results show that the drain saturation current increases and the threshold voltage decreases as drain voltage increases. Compared with the conventional model, the present model may offer more reasonable explanation for the drain-induced threshold voltage roll-off, the Early effect, and the channel length modulation effect. Furthermore, it is expected that the proposed model would provide more reasonable theoretical basis for analyzing various long and short channel InAlAs/InGaAs HEMT devices.

• Progress in Superconductivity and Cryogenics
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• v.15 no.2
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• pp.34-38
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• 2013

AC Losses for face to face stacks of four identical coated conductors (CCs) were numerically calculated using the H-formulation combined with the E-J power law and the Kim model. The motive sample was the face to face stack of four 2 mm-wide CC tapes with 2 ${\mu}m$ thick superconducting layer of which the critical current density, $J_c$, was $2.16{\times}10^6A/cm^2$ on IBAD-MgO template, which was suggested for the mitigation of ac loss as a round shaped wire by Korea Electrotechnology Research Institute. For the calculation the cross section of the stack was simply modeled as vertically aligned 4 rectangles of superconducting (SC) layers with $E=E_o(J(x,y,t)/J_c(B))^n$ in x-y plane where $E_o$ was $10^{-6}$ V/cm, $J_c$(B) was the field dependence of current density and n was 21. The field dependence of the critical current of the sample measured in four-probe method was employed for $J_c$(B) in the equation. The model was implemented in the finite element method program by commercial software. The ac loss properties for the stacks were compared with those of single 4 cm-wide SC layers with the same critical current density or the same critical current. The constraint for the simulation was imposed in two different ways that the total current of the stack obtained by integrating J(x,y,t) over the cross sections was the same as that of the applied transport current: one is that one fourth of the external current was enforced to flow through each SC. In this case, the ac loss values for the stacks were lower than those of single wide SC layer. This mitigation of the loss is attributed to the reduction of the normal component of the magnetic field near the SC layers due to the strong expulsion of the magnetic field by the enforced transport current. On the contrary, for the other case of no such enforcement, the ac loss values were greater than those of single 4cm-wide SC layer and. In this case, the phase difference of the current flowing through the inner and the outer SC layers of the stack was observed as the transport current was increased, which was a cause of the abrupt increase of ac loss for higher transport current.