• KSBB Journal
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• v.13 no.5
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• pp.502-510
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• 1998

Stabilization of antibody, which is specific to Salmonella typhimurium antigens, present in dry states on membranes was accomplished, and its shelf-life, i.e., duration for maintaining minimum 90% of the initial activity, under optimal conditions was determined. To prepare two major components of an immuno-strip, the antibody was not only immobilized on nitrocellulose membrane surfaces but also placed within the pores of glass fiber membrane after conjugating it with old colloids as signal generator. Among potential stabilizers of the immuno-components, a disaccharide, trehalose, showed a significant protection effect of immunoglobulin structure from thermal energy. Optimal concentrations of trehalose for the respective component were significantly different (8-fold higher for the antibody-gold conjugate than for the immobilized antibody), which probably resulted from distinct densities and configurations of antibody present on the membranes. An additional requirement for the gold conjugate was freeze-drying of this substance such that the conjugate can be readily resolubilized upon contact with aqueous medium. By using the components prepared under optimal conditions, immuno-strips were constructed and exposed to thermal energy. Signals with less than 10% decrease in the intensity were maintained for approximately 21 days at 60$^{\circ}C$. Compared to previous reports, this result represented a 2-year shelf-life at room temperature. it was, however, two times longer if determined from thermal acceleration tests based on the theory of inactivation rate of protein. Such discrepancy between the two estimates could be mainly attributed to errors in accurately controlling temperatures and also to changes in the physical properties of membranes due to a high thermal energy.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.105-105
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• 2016

Recently, high power impulse magnetron sputtering (HIPIMS) has attracted considerable attentions due to its high potential for industrial applications. By pulsing the sputtering target with high power density and short duration pulses, a high plasma density and high ionization of the sputtered species can be obtained. HIPIMS has exhibited several merits such as increased coating density, good adhesion, microparticle-free and smooth surface, which make the HIPIMS technique desirable for synthesizing hard coatings. However, hard coatings present intrinsic defects (columnar structures, pinholes, pores, discontinuities) which can affect the corrosion behavior, especially when substrates are active alloys like steel or in a wear-corrosion process. Atomic layer deposition (ALD), a CVD derived method with a broad spectrum of applications, has shown great potential for corrosion protection of high-precision metallic parts or systems. In ALD deposition, the growth proceeds through cyclic repetition of self-limiting surface reactions, which leads to the thin films possess high quality, low defect density, uniformity, low-temperature processing and exquisite thickness control. These merits make ALD an ideal candidate for the fabrication of excellent oxide barrier layer which can block the pinhole and other defects left in the coating structure to improve the corrosion protection of hard coatings. In this work, CrN/Al2O3/CrN multilayered coatings were synthesized by a hybrid process of HIPIMS and ALD techniques, aiming to improve the CrN hard coating properties. The influence of the Al2O3 interlayer addition, the thickness and intercalation position of the Al2O3 layer in the coatings on the microstructure, surface roughness, mechanical properties and corrosion behaviors were investigated. The results indicated that the dense Al2O3 interlayer addition by ALD lead to a significant decrease of the average grain size and surface roughness and greatly improved the mechanical properties and corrosion resistance of the CrN coatings. The thickness increase of the Al2O3 layer and intercalation position change to near the coating surface resulted in improved mechanical properties and corrosion resistance. The mechanism can be explained by that the dense Al2O3 interlayer acted as an excellent barrier for dislocation motion and diffusion of the corrosive substance.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.477-484
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• 2008

The Pacific saury, Cololabis saira Kwamaegi, is a traditional local food of the Eastern sea area, centered around Pohang. It is well-recognized as being both tasty and nutritious. Nevertheless, bacterial contamination, excessive dryness, and compositional changes render this fish edible only during the winter months. Thus, to improve its storage capabilities, this study assessed the effects of storage material, type, temperature, and duration on compositional changes in Kwamaegi. The assessed samples were Kwamaegi which had been naturally dried for 15 days. The storage materials included an A-film, a self- developed multi-film made of polyethylene, polyamide, EVOH, and polyethylene, and a B-film made of polyethylene, nylon, polyethylene, nylon, and polyethylene. The B films were utilized after pressing and lamination. The storage types included one whole fish(1G), or 2 divided fish(2G), to increase eating convenience. The 2G type was the muscle portion divided vertically after discarding the jowl, skin, and internal organs. The storage temperatures were 0, -15 and $-30^{\circ}C$, and the storage durations were 2, 4, and 6 months. Among the lipid rancidities, acid value and peroxide value showed the highest level of initial rancidity at a storage temperature of $0^{\circ}C$ for 2 months. We noted no significant differences between storage materials. The lower the storage temperatures, the less acid and peroxide were generated. Between the storage types, 1G evidenced lower less acid values than 2G. The TBA values revealed a dramatic increase at a storage temperature of $0^{\circ}C$ for 2 months, whereas this rapid progress was not observed at storage temperatures of -15 and $-30^{\circ}C$. Along with the acid value and peroxide value, the samples stored at 0, -15 and $-30^{\circ}C$ evidenced significantly lower TBA values. The B-film evidenced a slightly lower TBA value than was observed in the A-film, but no significant differences were observed.

• Journal of Korean Public Health Nursing
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• v.12 no.1
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• pp.116-131
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• 1998

This study was undertaken to obtain the menstrual patterns and menstrual discomforts in women university students. For the data collection, self-administered questionnaire survey was made from December 10, 1996 to January 20, 1997 among the 180 women university students in Seoul. The resultant data were processed by SAS program for frequency, proportion, and chi-square test. The results of this study are as follows ; 1) The mean age of the subjects was 20.6 years old. The mean height was 162cm and weight was 52.3Kg. $26.9\%$ of the subjects responded that they had experienced the unbalanced diet, $56\%$ the irregular meal, $39.6\%$intermittent dizziness, and $63.4\%$ the premenstrual syndrome. $53.7\%$ had feeling that skin temperature of their four extremities was 'a little lower than others'. The mean BMI(Body Mass Index) was 19.8, 'normal level' was $41.8\%$. $18.7\%$ responded that their characters were 'introspective ones'. The mean age of menache was 13.8 years old. The subjects responded that the mean number of pads they used per day during menstrual periods was 4.6 sheets. The mean duration of menstruation was 5.4 days, $10.4\%$ responded that their menstrual cycles were 'extremely regular', $44.8\%$ was 'regular', $36.6\%$ was 'a little irregular', and $8.2\%$ was 'extremely irregular'. Out of them who had experienced the dysmenorrhea, $21.3\%$ had family history of dysmenorrhea in connection with their mother and $35.0\%$ in their sisters. The mean of the first time that they experienced dysmenorrhea was 15 years old. $94\%$ of the subjects responded that they had experienced the dysmeorrhea. $47.6\%$ of the subjects responded that they experienced the dysmenorrhea 'monthly' and $52.4\%$ 'intermittently'. $53.0\%$ of them who had experienced dysmenorrhea responded that dysmenorrhea was the severest 'on the first menstrual day' and $22.4\%$ 'on the second day'. $48.8\%$ of them who had experienced dysmenorrhea responded that the most painful region was 'low abdomen'. $40\%$ of them who had experienced dysmenorrhea responded that they used 'analgesics' to soothe dysmenorrhea, $24.8\%$ used nothing, $18.4\%$ lay in their beds or slept, and $12\%$ made their 'low abdomen' warm. $70.3\%$ who had used analgesics because of dysmenorrhea took analgesics 'one or two times per month', $25.7\%$ 'intermittently', and $4.0\%$ more than 3 times per month. The analgesics which they used were 'geworin$(33.8\%)$,' 'penzal$(32.4\%)$', 'tyrenol$(18.9\%)$', and 'aspirin$(4.2\%)$'. $(47.9\%)$ of them who took analgesics because of dysmenorrhea responded that the duration of analgesics effect was '4 to 8 hours'. $15.1\%$ of them who experienced dysmenorrhea responded that they had visited the hospital. 2) The incidence of premenstrual syndrome was no significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 3) The incidence of dysmenorrhea was significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 4) The incidence of analgesics usage was significant difference according to the BMI, subjects with low BMI took more analgesics than those with normal BMI (p<.05). The incidence of analgesics usage was significant difference in accordance with pattern of meal. The women who had a meal regularly took more analgesics than those who had a meal irregularly(p<.05). But the incidence of analgesics usage was no significant difference in accordance with the unbalanced diet, characters, the incidence of dizziness, skin temperature of four extremities, the incidence of premenstrual syndrome.

• Korean Journal of Optics and Photonics
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• v.16 no.6
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• pp.535-541
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• 2005

We report on the development of a passively mode-locked near-infrared femtosecond laser with Cr:YAG crystal that operates near room temperature. The laser wavelength could easily be tuned by using only the internal prism pair over 110 nm from 1400 nm to 1510 nm in cw and over about 30 nm in mode-locked operation, respectively Maximum cw output powers of 810 mW were obtained with $1.5 \%$ output coupler for absorbed pump powers of 7.6 W. For compensation of the internal group velocity dispersion, an IR graded prism pair was used. The Cr:YAG laser delivered nearly Fourier-transform limited pulses with a pulse duration as short as 64 fs at 100 MHz repetition rate. In the mode-locked regime, the laser was operating at 1510 nm with a spectral bandwidth of 44 nm. In order to avoid unstable mode-locking and power instabilities, self-built tubes were inserted into the beam path in the resonator and purged with N2 gas. Finally, output powers of the Cr:YAG laser were optimized to 250 mW fer long time stable mode-locked operation.

• The Korean Journal of Applied Statistics
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• v.29 no.2
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• pp.331-344
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• 2016

Whole Crop Barley (WCB) is a representative self-sufficient winter annual forage crop, along with Italian Ryegrass (IRG), in Korea. In this study, we examined the path relationship between WCB yield and climate factors such as temperature, precipitation, and sunshine duration using a structural equation model. A Bayesian approach was considered to overcome the limitations of the small WCB sample size. As prior distribution of parameters in Bayesian method, standard normal distribution, the posterior result of structural equation model for WCB, and the posterior result of structural equation model for IRG (which is the most popular winter crop) were used. Also, Heywood case correction in prior distribution was considered to obtain the posterior distribution of parameters; in addition, the best prior to fit the characteristics of winter crops was identified. In our analysis, we found that the best prior was set by using the results of a structural equation model to IRG with Heywood case correction. This result can provide an alternative for research on forage crops that have hard to collect sample data.

• Reproductive and Developmental Biology
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• v.37 no.3
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• pp.155-159
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• 2013

This study was carried out to investigate synthetic extender for semen cryopreservation of Jeju Native Black Bull. The semen was collected using an artificial vagina and transported to the laboratory. The semen was diluted 1:1 by Tris-Egg yolk extender and contrifuged in 1,500 rpm for 15 minutes. The supernatant was removed. The pellect was diluted to final sperm concentration of $2{\times}10^8/ml$ by doubling in every 30 minutes at $4^{\circ}C$ cold chamber. The semen was equilibrated for 4 hours at cold chamber and packed to 0.5 ml straw. The semen straws were located above 5 cm for 10 minutes. The height and duration affect the freezing speed by temperature. The frozen straw was plunged to $LN_2$. The presented straws were examined the viability and motility after thawed at $37^{\circ}C$ water bath. Frozen-thawed sperm were evaluated sperm viability, membrane integrity and acrosome integrity. Post-thawed sperm viability has been significantly higher (p<0.05) in fresh sperm ($93.27{\pm}1.62%$) than frozen-thawed sperm ($73.34{\pm}3.27%$). However, there were no significant differences between fresh and frozen-thawed dead cell rate ($7.35{\pm}2.63$ vs, $13.71{\pm}2.85$). In sperm motility, between Triladyl and AndroMed Extender, there was no significant different ($72.86{\pm}2.83$ vs, $81.47{\pm}2.48$), similarly, the dead cell rates was similar ($18.41{\pm}3.42%$ and $17.26{\pm}4.25$). The results of our study suggest that AndroMed to the freezing extender showed more positive effect on the frozen-thawed spermatozoa in Jeju Native Black bull semen.