• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.1
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• pp.62-72
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• 2007

The purpose of present study was to determine whether different kinds of curing lights can alter microtensile bond strength(MTBS) of class I cavity pulpal and axial wall specimens in primary molar. Thirty clean mandibular 2nd primary molar's occlusal enamel were removed and class I cavity, size of $2{\times}4{\times}2mm$ was prepared. Dentin bonding agent was applied according to manufacturer's manual. Each group was cured with Halogen Curing Unit, Plasma Curing Unit and LED Curing Unit. Composite resin was bulk filled and photo cured with same curing unit. MTBS specimens which size is $0.7{\times}0.7{\times}4mm$ were prepared with low speed saw. Specimens were coded by their curing lights and wall positions (Halogen - Axial wall group, Halogen - Pulpal wall group, Plasma - Axial wall group, Plasma - Pulpal wall group, LED - Axial wall group, LED - Pulpal walt group). MTBS were tested at 1 mm/min cross Head speed by Universal Testing Machine. Fractured surface and bonding surface was observed with SEM. T-test between axial and pulpal specimens in each curing lights, one-way ANOVA among different curing light specimens in each wall positions were done. Weibull distribution analysis was done. The results were as follows : Mean MTBS of pulpal wall specimens were significantly greater than that of axial wall specimens at each curing units(p<.05). There was no significant difference in the MTBS among three curing units at axial wall and pulpal wall. In Weibull distribution, pulpal wall specimens were more homogeneous than axial wall specimens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1612-1620
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• 2015

Inflammation is a complex process involving a variety of immune cells, which defend the body from harmful stimuli. However, pro-inflammatory cytokines and inflammatory mediators can also exacerbate diseases such as cancer. Onion peel contains several phenolic compounds, including quercetin at an amount 20 times greater in peel than edible flesh. Therefore, in this study, the anti-inflammatory effects of onion peel ethanol extract (OPEE) were investigated lipopolysaccharide-induced inflammatory response. In our results, NO production decreased in a dose-dependent manner. Secretion of IL-6, $TNF-{\alpha}$, and $IL-1{\beta}$ was suppressed by 44%, 53%, and 60% respectively, at $100{\mu}g/mL$. Moreover, OPEE also suppressed expression of COX-2, iNOS, $NF-{\kappa}B$, and MAPKs in a dose-dependent manner. Formation of mice ear edema was reduced at the highest dose tested compared to the control, and reduction of ear thickness was observed in the histological analysis as well. In the acute toxicity test, no morality was observed in mice administered 5,000 mg/kg body weight of OPEE over a 2-week observation period. These results suggest that OPEE may have significant effects on inflammatory factors and be a potential anti-inflammatory material.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.350-359
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• 1993

The effect of gibberellic acid ($GA_3) and abscisic acid (ABA) on KCl-enhanced proteolysis of senescing leaves of rice(Oryza sativa L. cv. Chilsung) was studied. Emphasis was given to their effects on KCI-enhanced efflux of amino acids and proteinase activity. When treated singly, $GA_3 affected leaf proteolysis little, while ABA increased proteolysis, the rate of amino acid efflux, and ribulose -1,5 -bisphosphate carboxylase / oxygenase (Rubisco)-degrading endoproteinase activity. An additive increase in all three parameters mentioned above was observed when leaves were treated with ABA and KCl. No such an additive effect was found when $GA_3 was treated with KCl. Both $GA_3 and ABA helped to alleviate the KCI-suppressed activity of Rubisco-degrading exoproteinases. The additive increase in proteolysis of rice leaves in the presence of both ABA and KCl could thus be ascribed to a further increase in the efflux of protein hydrolyzates and Rubisco-degrading endoproteinase activity. An increase in proteolysis was accompanied by a decrease in water absorption, and the combined treatment of ABA with KCl resulted in a further reduction of water absorption.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.354-360
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• 2023

The diet composition of Tanaka's snailfish, Liparis tanakae were collected by bottom trawl net in the Yellow Sea of Korea during 2022 (April, August, October, and November). The size of the specimens ranged from 3.8 to 52.2 cm in total length. L. tanakae were primary consumed caridea shrimps (Crangon hakodatei, Eualus spathulirostris, etc.) and specialist feeder mainly consumed caridea shirmps (C. hakodatei). The L. tanakae's trophic level is 3.63. Caridea shrimps were the primary prey items for all size groups (<20 cm, 20~30 cm, 30~40 cm, ≥40 cm). The proportion of E. spathulirostris has increased as the body size of L. tanakae increased, whereas the proportion of C. hakodatei decreased gradually. As the body size of L. tanakae increased the mean weight of prey per stomach (mW/ST) tended to increase significantly (One-way ANOVA, P<0.05). The caridea shrimps were the primary prey items throught all seasons. In summer, the main prey items were the C. hakodatei, however, in autumn, the proportion of C. hakodatei decreased while the proportion of E. spathulirostris increased.

• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.265-272
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• 2002

In this study, we examined the effects of dietary fatty acids on the fatty acid composition of phospholipid fractions in regions of the brain and on behavioral development in rats. The Sprague Dawley rats were fed the experimental diets 3~4 wks prior to the conception. Experimental diets consisted of 10% fat(wt/wt) which were from either safflower oil (SO, poor in $\omega$3 fatty acids), mixed oil MO, P/M/S ratio : 1:1.4:1, $\omega$6/$\omega$3 ratio = 6.3), or mixed oil supplemented with vitamin E (+500 mg/kg diet). At 3 and 9 weeks of age, frontal cortex (FC), corpus striatum (CS), hippocampus (H), and cerebellum (CB) were dissected from the whole brain. The fatty acid content was determined in the different phospholipid fractions: phosphatidylcholine (PC), phosphatidyl-serine (PS), and phosphatidylethanolamine (PE) in the rat brain regions. In the visual discrimination test, the order of the cumulative errors made in Y-water maze test were SO > MO > ME. This suggested that the balanced diet supplemented with vitamin I had the most beneficial effect on learning ability. The overall characteristics of correlation between fatty acids and behavior development were that the frequency of cumulative errors were negatively correlated significantly with monounsaturated fatty acids (MUFAs), ie., 18:1 $\omega$9 and 22:1 $\omega$9. Docosa-hexaenoic acid (22:6 $\omega$3) of PS in frontal cortex (FC) was negatively correlated with the number of errors made in the Y-water maze test.22:5 $\omega$6 PS in hippocampus (H), PC and PE in corpus striatum (CS), PC in cerebellum (CB) were positively correlated with cumulative errors. And these errors were negatively correlated with 20:4 $\omega$ 6 of PE in corpus striatum (CS) and PC in cerebellum (CB). Especially, O1eic acid (18:1 u 9) in all phospholipid fractions (PC, PS, PE) of hippocampus was negatively correlated with the number of errors. These findings demonstrate that the MUFAs were might be essential for proper brain development, especially in hippocampus which is generally thought to be the regions of memory and learning.

• Journal of the Korean institute of surface engineering
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• v.41 no.5
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• pp.232-239
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• 2008

The dental orthodontic mini-screw requires good mechanical properties and high corrosion resistance for implantation in the bone. The purpose of this study was to investigate the electrochemical characteristics of TiN and ZrN coated orthodontic mini-screws, mini-screws were used for experiment. Ion plating was carried out for mini-screw using Ti and Zr coating materials with nitrogen gas. Ion plated surface of each specimen w as o bserved with f ield emission scanning e lectron microscopy ( FE-SEM), e nergy dispersive x-ray spectroscopy (EDX), and electrochemical tester. The surface of TiN and ZrN coated mini-screw were more smooth than that of other kinds of non-coated mini-screw due to dercrease of machined defects. The corrosion current density of the TiN and ZrN coated mini-screw decreased compared to non-coated sample. The corrosion potential of TiN and ZrN coated mini-screw were higher than that of non-coated mini-screw in 0.9% NaCl solution. The pitting corrosion resistance increased in the order of ZrN coated, TiN coated and non-coated wire. Pitting potential of ZrN coated mini-screw was the highest in the other specimens.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.23-23
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• 2003

김 붉은갯병은 김 엽체에 난균류 Pythium속의 Pythium porphyrae의 기생에 의해 발생되어 매년 김 양식에 큰 피해를 주는 매우 심각한 김 갯병중의 하나이다. 최근에는 이들 병해의 발생 및 억제를 위한 김 산처리제 (활성처리제) 남용에 따른 연안 양식어장의 생태계 파괴 및 김의 자연식품에 대한 이미지 훼손 등의 문제점이 대두되고 있다. 따라서 본 연구에서는 김 양식시 발생되는 붉은갯병의 병해를 억제하고자 활성처리제 처리시 고염분해수 처리를 병용함으로써 활성처리제의 사용을 최소화하면서 처리효과를 배가시키고자 하였다. 시험에 사용한 김 엽체는 2002년 10월에 전라남도 해남군 황산면 지선에서 채묘한 방사무늬김 (Porphyra yezoensis)을 육묘해 엽장 1cm 내외에서 냉동망을 제작하여 -2$0^{\circ}C$에 저장한 엽체를 자연해수 (약 27$\textperthousand$), 15$^{\circ}C$, 100$\mu$mol photon m$^{-2}$ s$^{-1}$, 광주기 9L : 15D의 배양조건하에서 15일간 배양한 엽장 3-4cm 정도의 것이었다. 활성처리제와 고염분해수처리제의 병용에 의한 붉은 갯병 억제효과는 붉은갯병 병원균의 유주자를 김 엽체에 감염시킨 후 27$\textperthousand$의 자연해수에 12일간 배양하면서 염분농도를 3-25%, 처리주기를 1-2회로 하여 각 시험구별 병해정도로 평가하였다. 고염분해수 처리에 의한 붉은갯병균 균사의 생장억제 효과는 김 엽체를 붉은갯병 병원균의 유주자로 감염시킨 다음 감염 12시간 후 염분농도를 3-25%로 처리한 후 27$\textperthousand$의 자연해수에 4일간 배양하면서 각 시험구별 배양시간에 따른 병원균 균사에 의한 김 엽체의 감염세포수로 평가하였다. 활성처리제와 고염분해수처리제의 병용이 김 엽체 생장에 미치는 영향은 건전한 김 엽체의 절편을 27$\textperthousand$의 자연해수에 배양하면서 시험구별로 활성처리와 고염분해수 (5, 10, 15, 20, 25%) 처리를 3일 간격으로 하면서 12일간 배양한 후 엽체의 엽면적 증가율로 평가하였다. 활성처리제와 고염분해수처리제의 병용에 의한 붉은갯병의 억제효과는 대조구 (활성처리 1회)와 비교해 주 2회의 활성처리구와 염분농도 20, 25% 처리구에서 병해 억제효과가 월등히 높았다. 고염분해수 처리에 의한 붉은갯병균 균사의 생장억제 효과는 염분농도 5, 10% 처리구의 경우 무처리구에 가까운 감염세포수를 보였으나, 염분농도 20, 25% 처리구의 경우 활성처리제 처리와 비슷한 감염세포수를 보여 뚜렷한 생장 억제효과를 나타냈다. 활성처리와 고염분해수 처리의 병용이 김 엽체 생장에 미치는 영향은 대조구 (활성처리 1회)의 3.4배 생장율과 활성처리와 염분농도 5-20%의 고염분해수 병용 처리구의 3.1-3.6배 생장율은 유의한 생장차이를 보이지 않았다 (P<0.05).

• Toxicological Research
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• v.18 no.1
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• pp.87-98
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• 2002

This study was conducted to evaluate the safety of a recombinant human Factor VIII(GC-$\gamma$ AHF) manufactured by Korea Green Cross Company with different technology according to the Regulation of Korean Food and Drug Administration (l 998. 12. 3). In acute toxicity test, both genders of Sprague-Dawley rats and Beagle dogs were administered intravenously with GC-$\gamma$ AHF of three doses (3,125, 625 and 125 IU/kg), and single dose of 3,125 IU/kg, respectively. No dead animal and abnormal autopsy findings were found in Control and GC-$\gamma$ AHF treated group. Therefore, the 50% lethal dose ($LD_{50}$) of GC-$\gamma$ AHF was conidered to be higher than 3,125 IU/kg in rats and dogs. In the four weeks repeated intravenous toxicity study, GC-$\gamma$ AHF was administrated intravenosly to both genders of rats and dogs with 3 doses (500, 150, 50 IU/kg). There were neither dead animals nor significant changes of body weights during the experimental Period. In addition, no significant GC-$\gamma$ AHF related changes were found in clinical sign, urinalysis and other finding. Statistically changes were observed in hematological, biochemical and organ weight parameters of treated groups: however these changes were not dose dependent. No histopathological lesion were observed in both control and treated animals. Above data suggest that no observed adverse effect level of test materials in rats and dogs might be over 500 IU/kg/day in this study. In ocular irritation test, any injury on iris, conjunctiva and cornea in rabbits were not observed. The acute ocular irritation index (A.O.I.), mean ocular irritation index (M.O.I.) and Day-7 individual ocular irritation Index (I.O.I.) of GC-$\gamma$ AHF were 0. In the primary skin Irritation test, the primary irritation index (P.I.I.) oj GC-$\gamma$ AHF were 0. Therefore, the GC-$\gamma$ AHF is considered not to have the primary skin and eye toxicity in rabbits. In active systemic anaphylaxis (ASA) test, GC-$\gamma$ AHF and GC-$\gamma$ AHF emulsified with Freund's complete adjuvant (FCA) did not induce any symptom of anaphylactic shock in guinea pigs. In passive cutaneous anaphylxis (PCA) test, after sensitization with antisera of GC-$\gamma$ AHF sensitized mice, blue spots were observed on the hypodermis of back of rats, but diameter of each spot was smaller than 5 mm in each test groups except the positive control group. Based on the results of this study, GC-$\gamma$ AHF is not conidered to have any antigenic potential. In conclusion, at levels of up to 500 IU/kg, GC-$\gamma$ AHF did not produce treatment-related toxicity under the conditions of these acute-, four week repeated-toxicity, primary skin and eye toxicity, and antigenicity test.

• Journal of Biomedical Engineering Research
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• v.33 no.2
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• pp.72-77
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• 2012

Phase Contrast MR Angiography(PC MRA) is excellent MRA technique for measuring the velocity of vessels in the human body. PC MRA need to at least four images for angiogram reconstruction and it caused longer scan time. Therefore, we used keyhole imaging combined PC MRA to reduce the scan time. However, keyhole imaging can lead the erroneous effects as loss of phase information or frequency discontinuous. In this study, we applied the keyhole imaging combined 2D PC MRA for improving the temporal resolution and also measured the velocity to evaluate the accuracy of phase information. We used 0.32T MRI scanner(Magfinder II, Scimedix, Korea). Using the 2D PC MRA pulse sequence, the vascular images for a human brain targeted on the Superior Sagittal Sinus(SSS) were obtained. We applied tukey window function for keyhole images to minimize the ringing artifact and erroneous factors that are induced frequency discontinuous and phase information loss. We also applied zero-padded algorithm to peripheral missing k-space lines to compare keyhole imaging results and the artifact power(AP) value was measured on the complex difference images to validate the image quality. Consider as based on our results, heavy image distortions and artifacts were shown until using at least 50% keyhole factor. Using above the 50% keyhole factors are shown well reconstructed and matched for magnitude images and velocity information measurements. In conclusion, we confirmed the image quality and velocity information of keyhole technique combined 2D PC MRA. Especially, measured velocity information through the keyhole imaging combination was similar to the velocity information of full sampled k-space image despite of frequency discontinuous and phase information loss in the keyhole imaging reconstruction process. Consequently, the keyhole imaging combined 2D PC MRA will give some clinical usefulness and advantages as improving the temporal resolution and measuring the velocity information via selecting the appropriate keyhole factor at low tesla MRI system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.5-5
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• 2009

Thin-film-transistors (TFTs) that can be prepared at low temperatures have attracted much attention because of the great potential for transparent and flexible electronics. One of the mainstreams in this field is the use of organic semiconductors such as pentacene. But device performance of the organic TFTs is still limited due to low field-effect mobility and rapid degradation after exposing to air. Alternative approach is the use of amorphous oxide semiconductors as a channel. Amorphous oxide semiconductors (AOSs) based TFTs showed the fast technological development, because AOS films can be fabricated at room temperature and exhibit the possibility in application like flexible display, electronic paper, and larges solar cells. Among the various AOSs, a-IGZO has lots of advantages because it has high channel mobility, uniform surface roughness and good transparency. [1] The high mobility is attributed to the overlap of spherical s-orbital of the heavy post-transition metal cations. This study demonstrated the effect of the variation in channel thickness from 30nm to 200nm on the TFT device performance. When the thickness was increased, turn-on voltage and subthreshold swing was decreased. The a-IGZO channels and source/drain metals were deposited with shadow mask. The a-IGZO channel layer was deposited on $SiO_2$/p-Si substrates by RF magnetron sputtering, where RF power is 150W. And working pressure is 3m Torr, at $O_2/Ar$ (2/28 sccm) atmosphere. The electrodes were formed with electron-beam evaporated Ti (30 nm) and Au (70 nm) bilayer. Finally, Al (150nm) as a gate metal was thermal-evaporated. TFT devices were heat-treated in a furnace at 250 $^{\circ}C$ and nitrogen atmosphere for 1hour. The electrical properties of the TFTs were measured using a probe-station. The TFT with channel thickness of 150nm exhibits a good subthreshold swing (SS) of 0.72 V/decade and on-off ratio of $1{\times}10^8$. The field effect mobility and threshold voltage were evaluated as 7.2 and 8 V, respectively.